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Sample records for glass batch preheater

  1. Waste heat recovery at the glass industry with the intervention of batch and cullet preheating

    Dolianitis Ioannis

    2016-01-01

    Full Text Available A promising option to reduce the specific energy consumption and CO2 emissions at a conventional natural gas fired container glass furnace deals with the advanced utilization of the exhaust gases downstream the air regenerators by means of batch and cullet preheating. A 3-dimensional computational model that simulates this process using mass and heat transfer equations inside a preheater has been developed. A case study for an efficient small-sized container glass furnace is presented dealing with the investigation of the impact of different operating and design configurations on specific energy consumption, CO2 emissions, flue gas energy recovery, batch temperature and preheater efficiency. In specific, the effect of various parameters is studied, including the preheater’s dimensions, flue gas temperature, batch moisture content, glass pull, combustion air excess and cullet fraction. Expected energy savings margin is estimated to 12-15%.

  2. Waste heat recovery at the glass industry with the intervention of batch and cullet preheating

    Dolianitis Ioannis; Giannakopoulos Dionysios; Hatzilau Christina-Stavrula; Karellas Sotirios; Kakaras Emmanuil; Nikolova Evelina; Skarpetis Georgios; Christodoulou Nikolaos; Giannoulas Nikolaos; Zitounis Theodoros

    2016-01-01

    A promising option to reduce the specific energy consumption and CO2 emissions at a conventional natural gas fired container glass furnace deals with the advanced utilization of the exhaust gases downstream the air regenerators by means of batch and cullet preheating. A 3-dimensional computational model that simulates this process using mass and heat transfer equations inside a preheater has been developed. A case study for an efficient small-sized containe...

  3. Energy saving options for glass furnaces & recovery of heat from their flue gases and experiences with batch & cullet pre-heaters applied in the glass industry

    Beerkens, R.G.C.

    2009-01-01

    Several measures, such as changes in batch composition (less batch humidity), or optimization of operating conditions, and limiting the combustion air excess, can lead to typically 2-8 % of energy savings of industrial glass furnaces. Larger energy savings are only possible by new furnace designs,

  4. Flexural Strength of Preheated Resin Composites and Bonding Properties to Glass-Ceramic and Dentin

    Matthias Richard Kramer

    2016-01-01

    Full Text Available To test the impact of preheating (25, 37, 54, or 68 °C of TetricEvoCeram (TEC, FiltekSupremeXT (FSXT, and Venus (V on flexural strength (FS, shear bond strength (SBS and interfacial tension (IFT. FS was tested with TEC and FSXT. For SBS, glass-ceramic and human dentin substrate were fabricated and luted with the preheated resin composite (RC. SBSs of 1500 thermal cycled specimens were measured. For IFT, glass slides covered with the non-polymerized RC were prepared and contact angles were measured. Data were analyzed using 2/1-way ANOVA with Scheffé-test, and t-test (p < 0.05. Preheated TEC (37–68 °C showed higher FS compared to the control-group (25 °C (p < 0.001. FSXT presented higher FS than TEC (p < 0.001. For SBS to dentin higher values for FSXT than TEC were found. The preheating temperature showed no impact on SBS to dentin. SBS to glass-ceramic revealed a positive influence of temperature for TEC 25–68 °C (p = 0.015. TEC showed higher values than V and FSXT (p < 0.001. IFT values increased with the preheating temperature. A significant difference could be observed in every RC group between 25 and 68 °C (p < 0.001.

  5. Effect of glass-batch makeup on the melting process

    Hrma, Pavel R.; Schweiger, Michael J.; Humrickhouse, Carissa J.; Moody, J. Adam; Tate, Rachel M.; Rainsdon, Timothy T.; Tegrotenhuis, Nathan E.; Arrigoni, Benjamin M.; Marcial, Jose; Rodriguez, Carmen P.; Tincher, Benjamin

    2010-01-01

    The response of a glass batch to heating is determined by the batch makeup and in turn determines the rate of melting. Batches formulated for a high-alumina nuclear waste to be vitrified in an all-electric melter were heated at a constant temperature-increase rate to determine changes in melting behavior in response to the selection of batch chemicals and silica grain-size as well as the addition of heat-generating reactants. The type of batch materials and the size of silica grains determine how much, if any, primary foam occurs during melting. Small quartz grains, 5 (micro)m in size, caused extensive foaming because their major portion dissolved at temperatures 800 C when batch gases no longer evolved. The exothermal reaction of nitrates with sucrose was ignited at a temperature as low as 160 C and caused a temporary jump in temperature of several hundred degrees. Secondary foam, the source of which is oxygen from redox reactions, occurred in all batches of a limited composition variation involving five oxides, B 2 O 3 , CaO, Li 2 O, MgO, and Na 2 O. The foam volume at the maximum volume-increase rate was a weak function of temperature and melt basicity. Neither the batch makeup nor the change in glass composition had a significant impact on the dissolution of silica grains. The impacts of primary foam generation on glass homogeneity and the rate of melting in large-scale continuous furnaces have yet to be established via mathematical modeling and melter experiments.

  6. Effect Of Glass-Batch Makeup On The Melting Process

    Kruger, A.A.; Hrma, P.

    2010-01-01

    The response of a glass batch to heating is determined by the batch makeup and in turn determines the rate of melting. Batches formulated for a high-alumina nuclear waste to be vitrified in an all-electric melter were heated at a constant temperature-increase rate to determine changes in melting behavior in response to the selection of batch chemicals and silica grain-size as well as the addition of heat-generating reactants. The type of batch materials and the size of silica grains determine how much, if any, primary foam occurs during melting. Small quartz grains, 5 (micro)m in size, caused extensive foaming because their major portion dissolved at temperatures 800 C when batch gases no longer evolved. The exothermal reaction of nitrates with sucrose was ignited at a temperature as low as 160 C and caused a temporary jump in temperature of several hundred degrees. Secondary foam, the source of which is oxygen from redox reactions, occurred in all batches of a limited composition variation involving five oxides, B 2 O 3 , CaO, Li 2 O, MgO, and Na 2 O. The foam volume at the maximum volume-increase rate was a weak function of temperature and melt basicity. Neither the batch makeup nor the change in glass composition had a significant impact on the dissolution of silica grains. The impacts of primary foam generation on glass homogeneity and the rate of melting in large-scale continuous furnaces have yet to be established via mathematical modeling and melter experiments.

  7. Copper solubility in DWPF, Batch 1 waste glass: Update report

    Schumacker, R.F.

    1992-01-01

    The ''Late Washing'' Step in the processing of precipitate will require the use of additional copper formate in the Precipitate Reactor to catalyze the hydrolysis reaction. The increased copper concentration in the melter feed increases the potential for metal precipitation during the vitrification of the melter feed. This report describes recent results with a conservative glass selected from the DWPF acceptable region in the Batch 1 Variability Study

  8. Potash - a key raw material of glass batch for Bohemian glasses from 14th-17th centuries?

    Cílová, Z.; Woitsch, Jiří

    2012-01-01

    Roč. 39, č. 2 (2012), s. 371-380 ISSN 0305-4403 R&D Projects: GA AV ČR KJB900580701 Institutional research plan: CEZ:AV0Z90580513 Keywords : Wood ash * Potash * Medieval glass * Chemical composition * Glass batch * archaeological experiment * Reconstruction of technology Subject RIV: AC - Archeology, Anthropology, Ethnology Impact factor: 1.889, year: 2012 http://www.sciencedirect.com/science/article/pii/S0305440311003505

  9. Kinetic model for quartz and spinel dissolution during melting of high-level-waste glass batch

    Pokorny, Richard; Rice, Jarrett A.; Crum, Jarrod V.; Schweiger, Michael J.; Hrma, Pavel

    2013-01-01

    The dissolution of quartz particles and the growth and dissolution of crystalline phases during the conversion of batch to glass potentially affects both the glass melting process and product quality. Crystals of spinel exiting the cold cap to molten glass below can be troublesome during the vitrification of iron-containing high-level wastes. To estimate the distribution of quartz and spinel fractions within the cold cap, we used kinetic models that relate fractions of these phases to temperature and heating rate. Fitting the model equations to data showed that the heating rate, apart from affecting quartz and spinel behavior directly, also affects them indirectly via concurrent processes, such as the formation and motion of bubbles. Because of these indirect effects, it was necessary to allow one kinetic parameter (the pre-exponential factor) to vary with the heating rate. The resulting kinetic equations are sufficiently simple for the detailed modeling of batch-to-glass conversion as it occurs in glass melters. The estimated fractions and sizes of quartz and spinel particles as they leave the cold cap, determined in this study, will provide the source terms needed for modeling the behavior of these solid particles within the flow of molten glass in the melter

  10. Investigation of Sludge Batch 3 (Macrobatch 4) Glass Sample Anomalous Behavior

    Bannochie, C. J.; Bibler, N. E.; Peeler, D. K.

    2005-01-01

    Two Defense Waste Processing Facility (DWPF) glass samples from Sludge Batch 3 (SB3) (Macrobatch 4) were received by the Savannah River National Laboratory (SRNL) on February 23, 2005. One sample, S02244, was designated for the Product Consistency Test (PCT) and elemental and radionuclide analyses. The second sample, S02247, was designated for archival storage. The samples were pulled from the melter pour stream during the feeding of Melter Feed Tank (MFT) Batch 308 and therefore roughly correspond to feed from Slurry Mix Evaporator (SME) Batches 306-308. During the course of preparing sample S02244 for PCT and other analyses two observations were made which were characterized as ''unusual'' or anomalous behavior relative to historical observations of glasses prepared for the PCT. These observations ultimately led to a series of scoping tests in order to determine more about the nature of the behavior and possible mechanisms. The first observation was the behavior of the ground glass fraction (-100 +200 mesh) for PCT analysis when contacted with deionized water during the washing phase of the PCT procedure. The behavior was analogous to that of an organic compound in the presence of water: clumping, floating on the water surface, and crawling up the beaker walls. In other words, the glass sample did not ''wet'' normally, displaying a hydrophobic behavior in water. This had never been seen before in 18 years SRNL PCT tests on either radioactive or non-radioactive glasses. Typical glass behavior is largely to settle to the bottom of the water filled beaker, though there may be suspended fines which result in some cloudiness to the wash water. The typical appearance is analogous to wetting sand. The second observation was the presence of faint black rings at the initial and final solution levels in the Teflon vessels used for the mixed acid digestion of S02244 glass conducted for compositional analysis. The digestion is composed of two stages, and at both the

  11. Radiological analysis of plutonium glass batches with natural/enriched boron

    Rainisch, R.

    2000-01-01

    The disposition of surplus plutonium inventories by the US Department of Energy (DOE) includes the immobilization of certain plutonium materials in a borosilicate glass matrix, also referred to as vitrification. This paper addresses source terms of plutonium masses immobilized in a borosilicate glass matrix where the glass components include both natural boron and enriched boron. The calculated source terms pertain to neutron and gamma source strength (particles per second), and source spectrum changes. The calculated source terms corresponding to natural boron and enriched boron are compared to determine the benefits (decrease in radiation source terms) for to the use of enriched boron. The analysis of plutonium glass source terms shows that a large component of the neutron source terms is due to (a, n) reactions. The Americium-241 and plutonium present in the glass emit alpha particles (a). These alpha particles interact with low-Z nuclides like B-11, B-10, and O-17 in the glass to produce neutrons. The low-Z nuclides are referred to as target particles. The reference glass contains 9.4 wt percent B 2 O 3 . Boron-11 was found to strongly support the (a, n) reactions in the glass matrix. B-11 has a natural abundance of over 80 percent. The (a, n) reaction rates for B-10 are lower than for B-11 and the analysis shows that the plutonium glass neutron source terms can be reduced by artificially enriching natural boron with B-10. The natural abundance of B-10 is 19.9 percent. Boron enriched to 96-wt percent B-10 or above can be obtained commercially. Since lower source terms imply lower dose rates to radiation workers handling the plutonium glass materials, it is important to know the achievable decrease in source terms as a result of boron enrichment. Plutonium materials are normally handled in glove boxes with shielded glass windows and the work entails both extremity and whole-body exposures. Lowering the source terms of the plutonium batches will make the handling

  12. TIME-TEMPERATURE-TRANSFORMATION DIAGRAMS FOR THE SLUDGE BATCH 3 - FRIT 418 GLASS SYSTEM

    Billings, A.; Edwards, Tommy

    2009-01-01

    As a part of the Waste Acceptance Product Specifications (WAPS) for Vitrified High-Level Waste Forms defined by the Department of Energy - Office of Environmental Management, the phase stability must be determined for each of the projected high-level waste (HLW) types at the Savannah River Site (SRS). Specifically, WAPS 1.4.1 requires the glass transition temperature (Tg) to be defined and time-temperature-transformation (TTT) diagrams to be developed. The Tg of a glass is an indicator of the approximate temperature where the supercooled liquid converts to a solid on cooling or conversely, where the solid begins to behave as a viscoelastic solid on heating. A TTT diagram identifies the crystalline phases that can form as a function of time and temperature for a given waste type or more specifically, the borosilicate glass waste form. In order to assess durability, the Product Consistency Test (PCT) was used and the durability results compared to the Environmental Assessment (EA) glass. The measurement of glass transition temperature and the development of TTT diagrams have already been performed for the seven Defense Waste Processing Facility (DWPF) projected compositions as defined in the Waste Form Compliance Plan (WCP). These measurements were performed before DWPF start-up and the results were incorporated in Volume 7 of the Waste Form Qualification Report (WQR). Additional information exists for other projected compositions, but overall these compositions did not consider some of the processing scenarios now envisioned for DWPF to accelerate throughput. Changes in DWPF processing strategy have required this WAPS specification to be revisited to ensure that the resulting phases have been bounded. Frit 418 was primarily used to process HLW Sludge Batch 3 (SB3) at 38% waste loading (WL) through the DWPF. The Savannah River National Laboratory (SRNL) fabricated a cache of glass from reagent grade oxides to simulate the SB3-Frit 418 system at a 38 wt % WL for glass

  13. Experimental investigation and optimisation of burner systems for glass melting ends with regenerative air preheating. Final report; Experimentelle Untersuchung und Optimierung von Brennersystemen fuer Glasschmelzwannen mit regenerativer Luftvorwaermung. Schlussbericht

    Scherello, A.; Flamme, M.; Kremer, H.

    2000-02-15

    The project comprised experiments on burner systems for glass melting ends with regenerative air preheating for the purpose of optimisation. The experimental set-up was to reflect realistic conditions. In the first stage of the investigations, modern burner systems were installed in a GWI test facility and investigated. [German] Ziel des oben genannten Forschungsvorhabens war die Durchfuehrung experimenteller Untersuchungen von Brennersystemen fuer Glasschmelzwannen mit regenerativer Luftvorwaermung sowie deren Optimierung. Dazu war es notwendig, einen experimentellen Aufbau zu realisieren, mit dessen Hilfe die Stroemungs-, Mischungs- und Umsetzungsphaenomene von Glasschmelzoefen realistisch nachgestellt und aussagekraeftige Untersuchungen durchgefuehrt werden koennen. In einem ersten Untersuchungsschritt wurden moderne Brennerlanzen an der GWI-Versuchsanlage installiert und untersucht. (orig.)

  14. Determination of heat conductivity of waste glass feed and its applicability for modeling the batch-to-glass conversion

    Hujová, Miroslava; Pokorný, R.; Kloužek, Jaroslav; Dixon, D.R.; Cutforth, D.A.; Lee, S.; McCarthy, B.P.; Schweiger, M. J.; Kruger, A.A.; Hrma, P.

    2017-01-01

    Roč. 100, č. 11 (2017), s. 5096-5106 ISSN 0002-7820 Institutional support: RVO:67985891 Keywords : foams * glassmelting * modelling/model * thermal conductivity Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 2.841, year: 2016

  15. Gravity mediated preheating

    Maity, Debaprasad

    2015-01-01

    In this work we propose a mechanism of natural preheating of our universe induced by the inflation field dependent effective mass term for the gravitational wave. For any single field inflationary model, the inflation must go through the oscillatory phase after the end of inflation. As has recently been shown, if the gravitational fluctuation has inflation dependent mass term, there will be a resonant amplification of the amplitude of the gravitational wave during the oscillatory phase of inflation though parametric resonance. Because of this large enhancement of the amplitude of the gravitational wave, we show that universe can be naturally pre-heated through a minimally coupled matter field with gravity. Therefore, during the pre-heating phase, there is no need to introduce any arbitrary coupling between the matter field and the inflation. (author)

  16. Analytical Plans Supporting The Sludge Batch 8 Glass Variability Study Being Conducted By Energysolutions And CUA's Vitreous State Laboratory

    Edwards, T. B.; Peeler, D. K.

    2012-01-01

    EnergySolutions (ES) and its partner, the Vitreous State Laboratory (VSL) of The Catholic University of America (CUA), are to provide engineering and technical services support to Savannah River Remediation, LLC (SRR) for ongoing operation of the Defense Waste Processing Facility (DWPF) flowsheet as well as for modifications to improve overall plant performance. SRR has requested via a statement of work that ES/VSL conduct a glass variability study (VS) for Sludge Batch 8. SRR issued a technical task request (TTR) asking that the Savannah River National Laboratory (SRNL) provide planning and data reduction support for the ES/VSL effort. This document provides two analytical plans for use by ES/VSL: one plan is to guide the measurement of the chemical composition of the study glasses while the second is to guide the measurement of the durability of the study glasses. The measurements generated by ES/VSL are to be provided to SRNL for data reduction and evaluation. SRNL is to review the results of its evaluation with ES/VSL and SRR. The results will subsequently be incorporated into a joint report with ES/VSL as a deliverable to SRR to support the processing of SB8 at DWPF

  17. Mechanism of Phase Formation in the Batch Mixtures for Slag-Bearing Glass Ceramics - 12207

    Stefanovsky, Sergey V.; Stefanovsky, Olga I.; Malinina, Galina A. [SIA Radon, 7th Rostovskii lane 2/14, Moscow 119121 (Russian Federation)

    2012-07-01

    Slag surrogate was produced from chemicals by heating to 900 deg. C and keeping at this temperature for 1 hr. The product obtained was intermixed with either sodium di-silicate (75 wt.% waste loading) or borax (85 wt.% slag loading). The mixtures were heat-treated within a temperature range of 25 to 1300 deg. C. The products were examined by X-ray diffraction and infrared spectroscopy. The products prepared at temperatures of up to 1000 deg. C contained both phase typical of the source slag and intermediate phases as well as phases typical of the materials melted at 1350 deg. C such as nepheline, britholite, magnetite and matrix vitreous phase. Vitrification process in batch mixtures consisting of slag surrogate and either sodium di-silicate or sodium tetraborate runs through formation of intermediate phases mainly silico-phosphates capable to incorporate Sm as trivalent actinides surrogate. Reactions in the batch mixtures are in the whole completed by ∼1000 deg. C but higher temperatures are required to homogenize the products. If in the borate-based system the mechanism is close to simple dissolution of slag constituents in the low viscous borate melt, then in the silicate-based system the mechanism was found to be much complicated and includes re-crystallization during melting with segregation of newly-formed nepheline type phase. (authors)

  18. Determination of heat conductivity of waste glass feed and its applicability for modeling the batch-to-glass conversion

    Hujova, Miroslava [Laboratory of Inorganic Materials, Joint Workplace of the University of Chemistry and Technology Prague and the Institute, Institute of Rock Structure and Mechanics of the ASCR, Prague Czech Republic; Pokorny, Richard [Laboratory of Inorganic Materials, Joint Workplace of the University of Chemistry and Technology Prague and the Institute, Institute of Rock Structure and Mechanics of the ASCR, Prague Czech Republic; Klouzek, Jaroslav [Laboratory of Inorganic Materials, Joint Workplace of the University of Chemistry and Technology Prague and the Institute, Institute of Rock Structure and Mechanics of the ASCR, Prague Czech Republic; Dixon, Derek R. [Radiological Materials & Detection Group, Pacific Northwest National Laboratory, Richland Washington; Cutforth, Derek A. [Radiological Materials & Detection Group, Pacific Northwest National Laboratory, Richland Washington; Lee, Seungmin [Radiological Materials & Detection Group, Pacific Northwest National Laboratory, Richland Washington; McCarthy, Benjamin P. [Radiological Materials & Detection Group, Pacific Northwest National Laboratory, Richland Washington; Schweiger, Michael J. [Radiological Materials & Detection Group, Pacific Northwest National Laboratory, Richland Washington; Kruger, Albert A. [U.S. Department of Energy, Office of River Protection, Richland Washington; Hrma, Pavel [Radiological Materials & Detection Group, Pacific Northwest National Laboratory, Richland Washington

    2017-07-10

    The heat conductivity of reacting melter feed affects the heat transfer and conversion process in the cold cap (the reacting feed floating on molten glass). To investigate it, we simulated the feed conditions and morphology in the cold-cap by preparing “fast-dried slurry blocks”, formed by rapidly evaporating water from feed slurry poured onto a 200°C surface. A heat conductivity meter was used to measure heat conductivity of samples cut from the fast-dried slurry blocks, samples of a cold cap retrieved from a laboratory-scale melter, and loose dry powder feed samples. Our study indicates that the heat conductivity of the feed in the cold cap is significantly higher than that of loose dry powder feed, resulting from the feed solidification during the water evaporation from the feed slurry. To assess the heat transfer at higher temperatures when feed turns into foam, we developed a theoretical model that predicts the foam heat conductivity based on morphology data from in-situ X-ray computed tomography. The implications for the mathematical modeling of the cold cap are discussed.

  19. Inflation After Preheating

    Felder, G; Linde, Andrei D; Tkachev, Igor I; Felder, Gary; Kofman, Lev; Linde, Andrei; Tkachev, Igor

    2000-01-01

    Preheating after inflation may lead to nonthermal phase transitions with symmetry restoration. These phase transitions may occur even if the total energy density of fluctuations produced during reheating is relatively small as compared with the vacuum energy in the state with restored symmetry. As a result, in some inflationary models one encounters a secondary, nonthermal stage of inflation due to symmetry restoration after preheating. We review the theory of nonthermal phase transitions and make a prediction about the expansion factor during the secondary inflationary stage. We then present the results of lattice simulations which verify these predictions, and discuss possible implications of our results for the theory of formation of topological defects during nonthermal phase transitions.

  20. Nuclear fuel preheating system

    Andrea, C.

    1975-01-01

    A nuclear reactor new fuel handling system which conveys new fuel from a fuel preparation room into the reactor containment boundary is described. The handling system is provided with a fuel preheating station which is adaptd to heat the new fuel to reactor refueling temperatures in such a way that the fuel is heated from the top down so that fuel element cladding failure due to thermal expansions is avoided. (U.S.)

  1. Preheating in new inflation

    Desroche, Mariel; Felder, Gary N.; Kratochvil, Jan M.; Linde, Andrei

    2005-01-01

    During the last ten years a detailed investigation of preheating was performed for chaotic inflation and for hybrid inflation. However, nonperturbative effects during reheating in the new inflation scenario remained practically unexplored. We investigate preheating in new inflation, using a combination of analytical and numerical methods. We find that the decay of the homogeneous component of the inflaton field and the resulting process of spontaneous symmetry breaking in the simplest models of new inflation usually occurs almost instantly: for the new inflation on the GUT scale it takes only about 5 oscillations of the field distribution. The decay of the homogeneous inflaton field is so efficient because of a combined effect of tachyonic preheating and parametric resonance. At that stage, the homogeneous oscillating inflaton field decays into a collection of waves of the inflaton field, with a typical wavelength of the order of the inverse inflaton mass. This stage usually is followed by a long stage of decay of the inflaton field into other particles, which can be described by the perturbative approach to reheating after inflation. The resulting reheating temperature typically is rather low

  2. Preheating with extra dimensions

    Tsujikawa, S.

    2000-01-01

    We investigate preheating in a higher-dimensional generalized Kaluza-Klein theory with a quadratic inflaton potential V(/φ) = /frac12 m 2 /φ 2 including metric perturbations explicitly. The system we consider is the multi-field model where there exists a dilaton field /σ which corresponds to the scale of compactifications and another scalar field /χ coupled to inflaton with the interaction frac12 g 2 /φ 2 /χ 2 +/g-tilde 2 /φ 3 /χ. In the case of g-tilde=0, we find that the perturbation of dilaton does not undergo parametric amplification while the χ field fluctuation can be enhanced in the usual manner by parametric resonance. In the presence of the /g-tilde 2 /φ 3 /χ coupling, the dilaton fluctuation in sub-Hubble scales is modestly amplified by the growth of metric perturbations for the large coupling g-tilde. In super-Hubble scales, the enhancement of the dilaton fluctuation as well as metric perturbations is weak, taking into account the backreaction effect of created /χ particles. We argue that not only is it possible to predict the ordinary inflationary spectrum in large scales but extra dimensions can be held static during preheating in our scenario. (author)

  3. ELIMINATION OF THE CHARACTERIZATION OF DWPF POUR STREAM SAMPLE AND THE GLASS FABRICATION AND TESTING OF THE DWPF SLUDGE BATCH QUALIFICATION SAMPLE

    Amoroso, J.; Peeler, D.; Edwards, T.

    2012-05-11

    A recommendation to eliminate all characterization of pour stream glass samples and the glass fabrication and Product Consistency Test (PCT) of the sludge batch qualification sample was made by a Six-Sigma team chartered to eliminate non-value-added activities for the Defense Waste Processing Facility (DWPF) sludge batch qualification program and is documented in the report SS-PIP-2006-00030. That recommendation was supported through a technical data review by the Savannah River National Laboratory (SRNL) and is documented in the memorandums SRNL-PSE-2007-00079 and SRNL-PSE-2007-00080. At the time of writing those memorandums, the DWPF was processing sludge-only waste but, has since transitioned to a coupled operation (sludge and salt). The SRNL was recently tasked to perform a similar data review relevant to coupled operations and re-evaluate the previous recommendations. This report evaluates the validity of eliminating the characterization of pour stream glass samples and the glass fabrication and Product Consistency Test (PCT) of the sludge batch qualification samples based on sludge-only and coupled operations. The pour stream sample has confirmed the DWPF's ability to produce an acceptable waste form from Slurry Mix Evaporator (SME) blending and product composition/durability predictions for the previous sixteen years but, ultimately the pour stream analysis has added minimal value to the DWPF's waste qualification strategy. Similarly, the information gained from the glass fabrication and PCT of the sludge batch qualification sample was determined to add minimal value to the waste qualification strategy since that sample is routinely not representative of the waste composition ultimately processed at the DWPF due to blending and salt processing considerations. Moreover, the qualification process has repeatedly confirmed minimal differences in glass behavior from actual radioactive waste to glasses fabricated from simulants or batch chemicals. In

  4. Elimination Of The Characterization Of DWPF Pour Stream Sample And The Glass Fabrication And Testing Of The DWPF Sludge Batch Qualification Sample

    Amoroso, J.; Peeler, D.; Edwards, T.

    2012-01-01

    A recommendation to eliminate all characterization of pour stream glass samples and the glass fabrication and Product Consistency Test (PCT) of the sludge batch qualification sample was made by a Six-Sigma team chartered to eliminate non-value-added activities for the Defense Waste Processing Facility (DWPF) sludge batch qualification program and is documented in the report SS-PIP-2006-00030. That recommendation was supported through a technical data review by the Savannah River National Laboratory (SRNL) and is documented in the memorandums SRNL-PSE-2007-00079 and SRNL-PSE-2007-00080. At the time of writing those memorandums, the DWPF was processing sludge-only waste but, has since transitioned to a coupled operation (sludge and salt). The SRNL was recently tasked to perform a similar data review relevant to coupled operations and re-evaluate the previous recommendations. This report evaluates the validity of eliminating the characterization of pour stream glass samples and the glass fabrication and Product Consistency Test (PCT) of the sludge batch qualification samples based on sludge-only and coupled operations. The pour stream sample has confirmed the DWPF's ability to produce an acceptable waste form from Slurry Mix Evaporator (SME) blending and product composition/durability predictions for the previous sixteen years but, ultimately the pour stream analysis has added minimal value to the DWPF's waste qualification strategy. Similarly, the information gained from the glass fabrication and PCT of the sludge batch qualification sample was determined to add minimal value to the waste qualification strategy since that sample is routinely not representative of the waste composition ultimately processed at the DWPF due to blending and salt processing considerations. Moreover, the qualification process has repeatedly confirmed minimal differences in glass behavior from actual radioactive waste to glasses fabricated from simulants or batch chemicals. In contrast, the

  5. Preheating curvaton perturbations

    Bastero-Gil, M.; Di Clemente, V.; King, S.F.

    2005-01-01

    We discuss the potentially important role played by preheating in certain variants of the curvaton mechanism in which isocurvature perturbations of a D-flat (and F-flat) direction become converted to curvature perturbations during reheating. We discover that parametric resonance of the isocurvature components amplifies the superhorizon fluctuations by a significant amount. As an example of these effects we develop a particle physics motivated model which involves hybrid inflation with the waterfall field N being responsible for generating the μ term, the right-handed neutrino mass scale, and the Peccei-Quinn symmetry breaking scale. The role of the curvaton field can be played either by usual Higgs field, or the lightest right-handed sneutrino. Our new results show that it is possible to achieve the correct curvature perturbations for initial values of the curvaton fields of order the weak scale. In this model we show that the prediction for the spectral index of the final curvature perturbation only depends on the mass of the curvaton during inflation, where consistency with current observational data requires the ratio of this mass to the Hubble constant to be 0.3

  6. Gravitational-wave mediated preheating

    Alexander, Stephon [Center for Cosmic Origins and Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States); Cormack, Sam, E-mail: samuel.c.cormack.gr@dartmouth.edu [Center for Cosmic Origins and Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 (United States); Marcianò, Antonino [Center for Field Theory and Particle Physics & Department of Physics, Fudan University, 200433 Shanghai (China); Yunes, Nicolás [Department of Physics, Montana State University, Bozeman, MT 59717 (United States); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106 (United States)

    2015-04-09

    We propose a new preheating mechanism through the coupling of the gravitational field to both the inflaton and matter fields, without direct inflaton–matter couplings. The inflaton transfers power to the matter fields through interactions with gravitational waves, which are exponentially enhanced due to an inflation–graviton coupling. One such coupling is the product of the inflaton to the Pontryagin density, as in dynamical Chern–Simons gravity. The energy scales involved are constrained by requiring that preheating happens fast during matter domination.

  7. Hybrid preheat/recirculating steam generator

    Lilly, G.P.

    1985-01-01

    The patent describes a hybrid preheat/recirculating steam generator for nuclear power plants. The steam generator utilizes recirculated liquid to preheat incoming liquid. In addition, the steam generator incorporates a divider so as to limit the amount of recirculating water mixed with the feedwater. (U.K.)

  8. Preheat operating experiences at the FFTF

    Tucker, W.R.

    1978-01-01

    The rather extensive test program performed on the FFTF preheat control system resulted in successful sodium fill of one secondary heat transport loop on July 2, 1978. The data obtained during testing and the attendant operating experience gained resulted in some design changes and provided the information necessary to fully characterize system performance. Temperature excursions and deviations from preset limits of only a minor nature were encountered during preheat for sodium fill. The addition of the rate alarm feature was beneficial to operation of the preheat system and allowed early detection and correction of impending excursions

  9. Glasses

    Dyre, Jeppe

    2004-01-01

    The temperature dependence of the viscosity of most glassforming liquids is known to depart significantly from the classical Arrhenius behaviour of simple fluids. The discovery of an unexpected correlation between the extent of this departure and the Poisson ratio of the resulting glass could lead...... to new understanding of glass ageing and viscous liquid dynamics....

  10. Products cooked in preheated versus non-preheated ovens. Baking times, calculated energy consumption, and product quality compared.

    Odland, D; Davis, C

    1982-08-01

    Plain muffins, yellow cake, baked custard, apple pie, tuna casserole, frozen tuna casserole, cheese soufflé, and meat loaf were baked in preheated and non-preheated standard gas, continuous-clean gas, standard electric, and self-cleaning electric ovens. Products generally required 5 min. or less extra baking time when cooked in non-preheated rather than in preheated ovens. The variability in baking times often was less between preheated and non-preheated ovens than among oven types. Calculated energy consumption values showed that usually less energy was required to bake products in non-preheated than in preheated ovens; savings averaged about 10 percent. Few significant differences were found in physical measurements or eating quality either between preheated and non-preheated ovens or among oven types. Overall, for the products tested, findings confirmed that preheating the oven is not essential for good product quality and, therefore, is an unnecessary use of energy.

  11. Dynamics of Symmetry Breaking and Tachyonic Preheating

    Felder, G; Greene, P B; Kofman, L A; Linde, Andrei D; Tkachev, Igor I; Felder, Gary; Garcia-Bellido, Juan; Greene, Patrick B.; Kofman, Lev; Linde, Andrei; Tkachev, Igor

    2001-01-01

    We reconsider the old problem of the dynamics of spontaneous symmetry breaking using 3d lattice simulations, and develop a theory of tachyonic preheating, which occurs due to the spinodal instability of the scalar field. Tachyonic preheating is so efficient that symmetry breaking typically completes within a single oscillation of the field distribution as it rolls towards the minimum of its effective potential. As an application of this theory we consider preheating in the hybrid inflation scenario, including SUSY-motivated F-term and D-term inflationary models. We show that preheating in hybrid inflation is typically tachyonic and the stage of oscillations of a homogeneous component of the scalar fields driving inflation ends after a single oscillation. Our results may also be relevant for the theory of the formation of disoriented chiral condensates in heavy ion collisions.

  12. Preheating Mechanism in F-term SUSY Hybrid Inflation

    Mazumdar, Arindam

    2012-01-01

    Supersymmetric F-term hybrid inflation is one of the most popular models of inflation. Preheating process occurs in this model via two different mechanism. Firstly the standard parametric resonance and secondly, the tachyonic preheating. Generally tachyonic preheating dominates the parametric resonance for this type of models. For different values of the parameters of the theory dominance of tachyonic preheating can vary.

  13. Elevated temperature forming method and preheater apparatus

    Krajewski, Paul E; Hammar, Richard Harry; Singh, Jugraj; Cedar, Dennis; Friedman, Peter A; Luo, Yingbing

    2013-06-11

    An elevated temperature forming system in which a sheet metal workpiece is provided in a first stage position of a multi-stage pre-heater, is heated to a first stage temperature lower than a desired pre-heat temperature, is moved to a final stage position where it is heated to a desired final stage temperature, is transferred to a forming press, and is formed by the forming press. The preheater includes upper and lower platens that transfer heat into workpieces disposed between the platens. A shim spaces the upper platen from the lower platen by a distance greater than a thickness of the workpieces to be heated by the platens and less than a distance at which the upper platen would require an undesirably high input of energy to effectively heat the workpiece without being pressed into contact with the workpiece.

  14. Gravitational radiation from preheating with many fields

    Jr, John T. Giblin; Price, Larry R.; Siemens, Xavier

    2010-01-01

    Parametric resonances provide a mechanism by which particles can be created just after inflation. Thus far, attention has focused on a single or many inflaton fields coupled to a single scalar field. However, generically we expect the inflaton to couple to many other relativistic degrees of freedom present in the early universe. Using simulations in an expanding Friedmann-Lemaître-Robertson-Walker spacetime, in this paper we show how preheating is affected by the addition of multiple fields coupled to the inflaton. We focus our attention on gravitational wave production — an important potential observational signature of the preheating stage. We find that preheating and its gravitational wave signature is robust to the coupling of the inflaton to more matter fields

  15. Gravitational radiation from preheating with many fields

    Jr, John T. Giblin [Department of Physics, Kenyon College, 201 North College Road, Gambier, OH 43022 (United States); Price, Larry R.; Siemens, Xavier, E-mail: giblinj@kenyon.edu, E-mail: larry@gravity.phys.uwm.edu, E-mail: siemens@gravity.phys.uwm.edu [Center for Gravitation and Cosmology, Department of Physics, University of Wisconsin — Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States)

    2010-08-01

    Parametric resonances provide a mechanism by which particles can be created just after inflation. Thus far, attention has focused on a single or many inflaton fields coupled to a single scalar field. However, generically we expect the inflaton to couple to many other relativistic degrees of freedom present in the early universe. Using simulations in an expanding Friedmann-Lemaître-Robertson-Walker spacetime, in this paper we show how preheating is affected by the addition of multiple fields coupled to the inflaton. We focus our attention on gravitational wave production — an important potential observational signature of the preheating stage. We find that preheating and its gravitational wave signature is robust to the coupling of the inflaton to more matter fields.

  16. Effects of dissipation and fluctuation in preheating

    Vartuli, Rodrigo; Ramos, Rudnei de O.

    2006-01-01

    In this paper, we study the effects of dissipation and fluctuation in preheating after inflation. The effective equation of motion for a scalar field χ interacting with lighter fields is derived using the field theoretical method of closed time path due to Schwinger, winch is suitable to study nonequilibrium and time dependent process. In this derivation the emergent equation is intrinsically dissipative and stochastic in nature. The resulting dynamics is then studied both analytically and numerically. The results obtained are then discussed for then relevance for the reheating epoch right after an inflationary phase(preheating) for the case of the evolution of the scalar field χ and its decay into fermion. (author)

  17. Simple air collectors for preheating fresh air

    Hensen, J.L.M.; Wit, de M.H.; Ouden, den C.

    1984-01-01

    In dwellings with mechanical ventilation systems the fresh air can easily be preheated by means of simple solar air systems. These can be an integral part of the building facade or roof and the costs are expected to be low. By means of computer experiments a large number of systems were evaluated.

  18. 7 CFR 58.919 - Pre-heat, pasteurization.

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Pre-heat, pasteurization. 58.919 Section 58.919... Procedures § 58.919 Pre-heat, pasteurization. When pasteurization is intended or required by either the vat... requirements outlined in § 58.128. Pre-heat temperatures prior to ultra pasteurization will be those that have...

  19. Metric preheating and limitations of linearized gravity

    Bassett, Bruce A.; Tamburini, Fabrizio; Kaiser, David I.; Maartens, Roy

    1999-01-01

    During the preheating era after inflation, resonant amplification of quantum field fluctuations takes place. Recently it has become clear that this must be accompanied by resonant amplification of scalar metric fluctuations, since the two are united by Einstein's equations. Furthermore, this 'metric preheating' enhances particle production, and leads to gravitational rescattering effects even at linear order. In multi-field models with strong preheating (q>>1), metric perturbations are driven non-linear, with the strongest amplification typically on super-Hubble scales (k→0). This amplification is causal, being due to the super-Hubble coherence of the inflaton condensate, and is accompanied by resonant growth of entropy perturbations. The amplification invalidates the use of the linearized Einstein field equations, irrespective of the amount of fine-tuning of the initial conditions. This has serious implications on all scales - from large-angle cosmic microwave background (CMB) anisotropies to primordial black holes. We investigate the (q,k) parameter space in a two-field model, and introduce the time to non-linearity, t nl , as the timescale for the breakdown of the linearized Einstein equations. t nl is a robust indicator of resonance behavior, showing the fine structure in q and k that one expects from a quasi-Floquet system, and we argue that t nl is a suitable generalization of the static Floquet index in an expanding universe. Backreaction effects are expected to shut down the linear resonances, but cannot remove the existing amplification, which threatens the viability of strong preheating when confronted with the CMB. Mode-mode coupling and turbulence tend to re-establish scale invariance, but this process is limited by causality and for small k the primordial scale invariance of the spectrum may be destroyed. We discuss ways to escape the above conclusions, including secondary phases of inflation and preheating solely to fermions. The exclusion principle

  20. Are black holes overproduced during preheating?

    Suyama, Teruaki; Tanaka, Takahiro; Bassett, Bruce; Kudoh, Hideaki

    2005-01-01

    We provide a simple but robust argument that primordial black hole production generically does not exceed astrophysical bounds during the resonant preheating phase after inflation. This conclusion is supported by fully nonlinear lattice simulations of various models in two and three dimensions which include rescattering but neglect metric perturbations. We examine the degree to which preheating amplifies density perturbations at the Hubble scale and show that, at the end of the parametric resonance, power spectra are universal, with no memory of the power spectrum at the end of inflation. In addition, we show how the probability distribution of density perturbations changes from exponential on very small scales to Gaussian when smoothed over the Hubble scale - the crucial length for studies of primordial black hole formation - hence justifying the standard assumption of Gaussianity

  1. Influence of preheating on grindability of coal

    Lytle, J.; Choi, N.; Prisbrey, K.

    1992-01-01

    Enormous quantities of coal must be ground as feed to power generation facilities. The energy cost of grinding is significant at 5 to 15 kWh/ton. If grindability could be increased by preheating the coal with waste heat, energy costs could be reduced. The objective of this work was to determine how grindability was affected by preheating. The method was to use population balance grinding models to interpret results of grinding coal before and after a heat treatment. Simulation of locked cycle tests gave a 40% increase in grindability. Approximately 40% grinding energy saving can be expected. By using waste heat for coal treatment, the targeted energy savings would be maintained. ?? 1992.

  2. Nuclear reactor insulation and preheat system

    Wampole, N.C.

    1978-01-01

    An insulation and preheat system is disclosed for preselected components of a fluid cooled nuclear reactor. A gas tight barrier or compartment of thermal insulation surrounds the selected components and includes devices to heat the internal atmosphere of the ocmpartment. An external surface of the compartment of enclosure is cooled, such as by a circulating fluid. The heating devices provide for preheating of the components, as well as maintenance of a temperature sufficient to ensure that the reactor coolant fluid will not solidify during shutdown. The external cooling limits the heat transferred to other plant structures, such as supporting concrete and steel. The barrier is spaced far enough from the surrounded components so as to allow access for remote or manual inspection, maintenance, and repair

  3. Preheating of tap water with solar collectors

    Granum, H; Raaen, H

    1992-05-05

    In 1991 SINTEF Architecture and Building Technology won the second prize in 'The Nordic Competition for Low Energy Buildings' with a project proposal named 'LOWe'. The paper gives a description of the energy-saving features of this project, particularly the use of a solar collector for preheating of tap water. Compared with the economic profitability of other saving efforts in the project, such as good thermal insulation and efficient heat recovering system, the system for solar preheating of tap water does not seem very attractive for the time being. Loose estimates indicate a cost of close of NOK 1.00 per kWh for the produced energy in the solar collector, while the present price for electricity in Norway is about NOK 0.50 per kWh. Compared with a heat pump solution however the energy cost is not unreasonable.

  4. Pre-heating mitigates composite degradation.

    Silva, Jessika Calixto da; Rogério Vieira, Reges; Rege, Inara Carneiro Costa; Cruz, Carlos Alberto dos Santos; Vaz, Luís Geraldo; Estrela, Carlos; Castro, Fabrício Luscino Alves de

    2015-01-01

    Dental composites cured at high temperatures show improved properties and higher degrees of conversion; however, there is no information available about the effect of pre-heating on material degradation. Objectives This study evaluated the effect of pre-heating on the degradation of composites, based on the analysis of radiopacity and silver penetration using scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS). Material and Methods Thirty specimens were fabricated using a metallic matrix (2x8 mm) and the composites Durafill VS (Heraeus Kulzer), Z-250 (3M/ESPE), and Z-350 (3M/ESPE), cured at 25°C (no pre-heating) or 60°C (pre-heating). Specimens were stored sequentially in the following solutions: 1) water for 7 days (60°C), plus 0.1 N sodium hydroxide (NaOH) for 14 days (60°C); 2) 50% silver nitrate (AgNO3) for 10 days (60°C). Specimens were radiographed at baseline and after each storage time, and the images were evaluated in gray scale. After the storage protocol, samples were analyzed using SEM/EDS to check the depth of silver penetration. Radiopacity and silver penetration data were analyzed using ANOVA and Tukey's tests (α=5%). Results Radiopacity levels were as follows: Durafill VSZ-350>Z-250 (pheated specimens presented higher radiopacity values than non-pre-heated specimens (pheated specimens (pheating at 60°C mitigated the degradation of composites based on analysis of radiopacity and silver penetration depth.

  5. Spectroscopic Measurements of Target Preheating on OMEGA

    Elton, R.C.; Griem, H.R.; Iglesias, E.J.

    2000-01-01

    The preheating of laser-heated microballoon targets has been measured by time-resolved x-ray and extreme ultraviolet (euv) spectroscopy on the 30 kJ, 351 nm, 60-beam laser-fusion system at the University of Rochester Laboratory for Laser Energetics. Thin coatings of aluminum overcoated with magnesium served as indicators. both the sequence of the x-ray line emission and the intensity of euv radiation were used to determine a preheating peaking at ∼ 10 ns prior to onset of the main laser pulse, with a power density ≅1% of the main pulse. The measurements are supported by numerical modeling. Further information is provided by absorption spectra from the aluminum coating, backlighted by continuum from the heated surface. The exact source of the preheating energy remains unknown at present, but most likely arrives from early laser leakage through the system. The present target diagnostic is particularly useful when all beams cannot be monitored directly at all laser wavelengths

  6. CRYSTALLIZATION IN MULTICOMPONENT GLASSES

    KRUGER AA; HRMA PR

    2009-10-08

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  7. Crystallization In Multicomponent Glasses

    Kruger, A.A.; Hrma, P.R.

    2009-01-01

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  8. Sintering uranium oxide using a preheating step

    Jensen, N.J.; Nivas, Y.; Packard, D.R.

    1977-01-01

    Compacted pellets of uranium oxide or uranium oxide with one or more additives are heated in a kiln in a process having a preheating step, a sintering step, a reduction step, and a cooling step in a controlled atmosphere. The process is practiced to give a range of temperature and atmosphere conditions for obtaining optimum fluoride removal from the compacted pellets along with optimum sintering in a single process. The preheating step of this process is conducted in a temperature range of about 600 0 to about 900 0 C and the pellets are held for at least twenty min, and preferably about 60 min, in an atmosphere having a composition in the range of about 10 to about 75 vol % hydrogen with the balance being carbon dioxide. The sintering step is conducted at a temperature in the range of about 900 0 C to 1500 0 C in the presence of an atmosphere having a composition in the range of about 0.5 to about 90 vol % hydrogen with the balance being carbon dioxide. The reduction step reduces the oxygen to metal ratio of the pellets to a range of about 1.98 to 2.10:1 and this is accomplished by gradually cooling the pellets for about 30 to about 120 min from the temperature of the sintering step to about 1100 0 C in an atmosphere of about 10 to 90 vol % hydrogen with the balance being carbon dioxide. Thereafter the pellets are cooled to about 100 0 C under a protective atmosphere, and in one preferred practice the same atmosphere used in the reduction step is used in the cooling step. The preheating, sintering and reduction steps may also be conducted with their respective atmospheres having an initial additional component of water vapor and the water vapor can comprise up to about 20 vol %

  9. From (p)reheating to nucleosynthesis

    Jedamzik, Karsten

    2002-01-01

    This paper gives a brief qualitative description of the possible evolution of the early universe between the end of an inflationary epoch and the end of big-bang nucleosynthesis. After a general introduction, establishing the minimum requirements cosmologists impose on this cosmic evolutionary phase, namely, successful baryogenesis, the production of cosmic dark matter and successful light-element nucleosynthesis, a more detailed discussion on some recent developments follows. This latter includes the physics of preheating, the putative production of (alternative) dark matter and the current status of big bang nucleosynthesis

  10. When can preheating affect the CMB?

    Tsujikawa, Shinji; Bassett, Bruce A.

    2002-05-01

    We discuss the principles governing the selection of inflationary models for which preheating can affect the CMB. This is a (fairly small) subset of those models which have nonnegligible entropy/isocurvature perturbations on large scales during inflation. We study new models which belong to this class-two-field inflation with negative nonminimal coupling and hybrid/double/supernatural inflation models where the tachyonic growth of entropy perturbations can lead to the variation of the curvature perturbation, /R, on super-Hubble scales. Finally, we present evidence against recent claims for the variation of /R in the absence of substantial super-Hubble entropy perturbations.

  11. Preheating the universe in hybrid inflation

    García-Bellido, J

    1998-01-01

    One of the fundamental problems of modern cosmology is to explain the origin of all the matter and radiation in the Universe today. The inflationary model predicts that the oscillations of the scalar field at the end of inflation will convert the coherent energy density of the inflaton into a large number of particles, responsible for the present entropy of the Universe. The transition from the inflationary era to the radiation era was originally called reheating, and we now understand that it may consist of three different stages: preheating, in which the homogeneous inflaton field decays coherently into bosonic waves (scalars and/or vectors) with large occupation numbers; backreaction and rescattering, in which different energy bands get mixed; and finally decoherence and thermalization, in which those waves break up into particles that thermalize and acquire a black body spectrum at a certain temperature. These three stages are non-perturbative, non-linear and out of equilibrium, and we are just beginning ...

  12. Recycling of post-consumer glass: energy savings, CO2 emission reduction, effects on glass quality and glass melting

    Beerkens, R.G.C.; Kers, G.; Santen, E. van

    2011-01-01

    This presentation shows the advantages of re-melting post-consumer glass, but also the potential risks of using contaminated cullet in the raw material batch of glass furnaces (e.g. container glass furnaces). As an example of potential advantages: increasing the cullet % in the batch of an efficient

  13. Pro Spring Batch

    Minella, Michael T

    2011-01-01

    Since its release, Spring Framework has transformed virtually every aspect of Java development including web applications, security, aspect-oriented programming, persistence, and messaging. Spring Batch, one of its newer additions, now brings the same familiar Spring idioms to batch processing. Spring Batch addresses the needs of any batch process, from the complex calculations performed in the biggest financial institutions to simple data migrations that occur with many software development projects. Pro Spring Batch is intended to answer three questions: *What? What is batch processing? What

  14. Gravitational wave production from preheating: parameter dependence

    Figueroa, Daniel G. [Theory Division, CERN, 1211 Geneva (Switzerland); Torrentí, Francisco, E-mail: daniel.figueroa@cern.ch, E-mail: f.torrenti@csic.es [Instituto de Física Teórica IFT-UAM/CSIC, Universidad Autónoma de Madrid, Cantoblanco 28049 Madrid, Spain. (Spain)

    2017-10-01

    Parametric resonance is among the most efficient phenomena generating gravitational waves (GWs) in the early Universe. The dynamics of parametric resonance, and hence of the GWs, depend exclusively on the resonance parameter q . The latter is determined by the properties of each scenario: the initial amplitude and potential curvature of the oscillating field, and its coupling to other species. Previous works have only studied the GW production for fixed value(s) of q . We present an analytical derivation of the GW amplitude dependence on q , valid for any scenario, which we confront against numerical results. By running lattice simulations in an expanding grid, we study for a wide range of q values, the production of GWs in post-inflationary preheating scenarios driven by parametric resonance. We present simple fits for the final amplitude and position of the local maxima in the GW spectrum. Our parametrization allows to predict the location and amplitude of the GW background today, for an arbitrary q . The GW signal can be rather large, as h {sup 2Ω}{sub GW}( f {sub p} ) ∼< 10{sup −11}, but it is always peaked at high frequencies f {sub p} ∼> 10{sup 7} Hz. We also discuss the case of spectator-field scenarios, where the oscillatory field can be e.g. a curvaton, or the Standard Model Higgs.

  15. A New Laser Preheat Protocol For Maglif

    Weis, M. R.; Harvey-Thompson, A. J.; Geissel, M.; Jennings, C. A.; Peterson, K. J.; Glinsky, M. E.; Awe, T. J.; Bliss, D. E.; Gomez, M. R.; Harding, E. C.; Hansen, S. B.; Kimmel, M. W.; Knapp, P. F.; Lewis, S. M.; Porter, J. L.; Rochau, G. A.; Schollmeier, M.; Schwarz, J.; Shores, J. E.; Slutz, S. A.; Sinars, D. B.; Smith, I. C.; Speas, C. S.

    2017-10-01

    Previous Magnetized Liner Inertial Fusion experiments at Sandia National Labs have preheated the fuel with the unsmoothed 2 ω Z-Beamlet Laser. A new low intensity laser configuration, using phase plate smoothing and a low-power pulse shape, improved laser propagation and reduced stimulated Brillouin scattering in offline laser experiments. This allows for more efficient use of laser energy and better spot reproducibility. The new laser protocol is estimated to couple at least 650 J to the fuel, sufficient to produce comparable neutron yields with the previous unsmoothed configuration. Mid-Z dopants were also fielded on the underside of the window. Observation of these dopants provided evidence of window material mixing into the fuel with both the unsmoothed and smoothed beam, consistent with MHD simulation predictions. Sandia National Laboratories is a multi-mission laboratory managed and operated by NTESS, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the U.S. DOE's NNSA under contract DE-NA0003525.

  16. Prediction of flame formation in highly preheated air combustion

    Yang, Jang Sik; Choi, Gyung Min; Kim, Duck Jool; Katsuki, Masashi

    2008-01-01

    Fundamental information about the ignition position and shape of a flame in highly preheated air combustion was obtained, and the suitability of the suggested reduced kinetic mechanism that reflects the characteristics of the highly preheated air combustion was demonstrated. Flame lift height and flame length with variations of premixed air temperature and oxygen concentration were measured by CH chemiluminescence intensity, and were computed with a reduced kinetic mechanism. Flame attached near a fuel nozzle started to lift when preheated air temperature became close to auto-ignition temperature and/or oxygen concentration reduced. The flame lift height increased but the flame length decreased with decreasing preheated air temperature and flame length reversed after a minimum value. Calculated results showed good agreement with those of experiment within tolerable error. Flame shape shifted from diffusion flame shape to partial premixed flame shape with increasing lift height and this tendency was also observed in the computation results

  17. Prediction of flame formation in highly preheated air combustion

    Yang, Jang Sik; Choi, Gyung Min; Kim, Duck Jool [Pusan National University, Busan (Korea, Republic of); Katsuki, Masashi [Osaka University, Osaka (Japan)

    2008-11-15

    Fundamental information about the ignition position and shape of a flame in highly preheated air combustion was obtained, and the suitability of the suggested reduced kinetic mechanism that reflects the characteristics of the highly preheated air combustion was demonstrated. Flame lift height and flame length with variations of premixed air temperature and oxygen concentration were measured by CH chemiluminescence intensity, and were computed with a reduced kinetic mechanism. Flame attached near a fuel nozzle started to lift when preheated air temperature became close to auto-ignition temperature and/or oxygen concentration reduced. The flame lift height increased but the flame length decreased with decreasing preheated air temperature and flame length reversed after a minimum value. Calculated results showed good agreement with those of experiment within tolerable error. Flame shape shifted from diffusion flame shape to partial premixed flame shape with increasing lift height and this tendency was also observed in the computation results

  18. Numerical Simulation of Anisotropic Preheating Ablative Rayleigh–Taylor Instability

    Li-Feng, Wang; Wen-Hua, Ye; Ying-Jun, Li

    2010-01-01

    The linear growth rate of the anisotropic preheating ablative Rayleigh–Taylor instability (ARTI) is studied by numerical simulations. The preheating model κ(T) = κ SH [1 + f(T)] is applied, where f(T) is the preheating function interpreting the preheating tongue effect in the cold plasma ahead of the ablative front. An arbitrary coefficient D is introduced in the energy equation to study the influence of transverse thermal conductivity on the growth of the ARTI. We find that enhancing diffusion in a plane transverse to the mean longitudinal flow can strongly reduce the growth of the instability. Numerical simulations exhibit a significant stabilization of the ablation front by improving the transverse thermal conduction. Our results are in general agreement with the theory analysis and numerical simulations by Masse [Phys. Rev. Lett. 98 (2007) 245001]. (physics of gases, plasmas, and electric discharges)

  19. Numerical simulation of anisotropic preheating ablative Rayleigh-Taylor instability

    Wang Lifeng; Ye Wenhua; Li Yingjun

    2010-01-01

    The linear growth rate of the anisotropic preheating ablative Rayleigh-Taylor instability (ARTI) is studied by numerical simulations. The preheating model κ(T)=κ SH [1+f(T)] is applied, where f(T) is the preheating function interpreting the preheating tongue effect in the cold plasma ahead of the ablative front. An arbitrary coefficient D is introduced in the energy equation to study the influence of transverse thermal conductivity on the growth of the ARTI. We find that enhancing diffusion in a plane transverse to the mean longitudinal flow can strongly reduce the growth of the instability. Numerical simulations exhibit a significant stabilization of the ablation front by improving the transverse thermal conduction. Our results are in general agreement with the theory analysis and numerical simulations by Masse. (authors)

  20. Effect of inflation on parametric resonance during preheating

    Hirai, Shiro

    2002-01-01

    The effect of inflation on parametric resonance during preheating is investigated. The behaviour of the preheating scalar field during inflation is investigated and is found to become squeezed in cases ranging from small-scale cases to large-scale cases. However, the positive-frequency solution is usually adopted in the initial condition of the scalar field at preheating. Although large squeezing occurs during inflation, the difference in the comoving occupation number of particles n k between two initial conditions is shown to be not so large. Rather, the ratio n k varies from 0.2 to 5.0, depending on k. In order to clarify this situation, we introduce the squeeze formulation. The squeeze parameters r and φ are calculated not only in preheating, but also in inflation. Since the squeeze parameters are calculated from inflation to preheating, we can clarify the behaviour of the parametric resonance. In preheating, the behaviour of r is shown to remain relatively unchanged with respect to k; however, the squeeze angle φ displays different behaviour for large-scale cases and small-scale cases

  1. Behavior of the turbine - regenerating preheaters functional assembly

    Bigu, Melania; Nita, Iulian Pavel; Tenescu, Mircea

    2004-01-01

    In the classical calculation of pressure distribution in the turbine-regenerating heaters' assembly a uniform distribution of feedwater enthalpy rise at each regenerating preheating step is usually assumed. This is accurately enough as a basis of designing of the preheating installation operating at rated power regime. But at partial regimes this is not totally valid since the preheaters are already shaped and the quasi-equal distribution does not satisfy the equation system describing the heat transfer correlations in these installations. A more detailed analysis shows that pressure in the feeding line preheaters and the bleeding steam flow rates at the turbine outlets are described physically by solving simultaneously the equations of hydrodynamic flow through the turbine and the equations of the heat transfer in the preheaters of the feedwater preheating line. This work approaches this more accurate solving method at least from a theoretical standing point; two cases are illustrated in the annexes of the work: a case of a secondary circuit with a single regenerating inlet and a case with two regenerating inlets. A classical - Panzer method of transformation of a many regenerative stages scheme may lead to one or another of the above cases. (authors)

  2. Susceptibility of CANDU steam generator preheater to cavitation erosion

    Laroche, S.L.; Sun, L.; Pietralik, J.M.

    2012-01-01

    In 2009, Darlington Steam Generator (SG) tube inspections revealed some tubes had degraded in the preheater. The tube degradation occurred at the clearance gap between the tube and the preheater baffle and reached up to 50% through-wall depth at the baffles in the middle portion of the preheater. The general pattern of the damage and the elemental composition analysis suggested that the degradation was the result of a hydrodynamic process, such as cavitation erosion. Cavitation erosion occurs when vapour bubbles exist or form in the flowing liquid and then these bubbles collapse violently in the vicinity of the wall. These bubbles collapse when steam bubbles contact water that is sufficiently subcooled, below the saturation temperature. In the gap between the tube and the preheater baffle, low flow will exist due to the pressure difference across the baffle plate. In addition, heat transfer occurs from the primary-side fluid to the secondary-side fluid within this clearance gap that is driven by the primary-to-secondary temperature difference. Factors, such as the tube position in the baffle hole and fouling, influence the local conditions and can cause subcooled boiling that result in cavitation. This paper presents a study of flow and heat transfer phenomena to determine the factors contributing to cavitation erosion in SG preheaters. The analysis used the THIRST1 code for a 3-dimensional thermalhydraulic simulation of the steam generators and the ANSYS FLUENT®2 code for detailed calculations of flow and heat transfer in the clearance gaps. This study identifies that tubes in the preheater region are susceptible to cavitation erosion and indicates that this area should be part of the station inspection program because, regardless of preheater design, some tubes may experience the thermalhydraulic conditions and undergo degradations similar to those observed for the tubes in Darlington SGs. (author)

  3. The effect of preheating on the IRSL signal from feldspar

    Murray, A.S.; Buylaert, J.P.; Thomsen, Kristina Jørkov

    2009-01-01

    between the loss of blue IRSL and TL signals with preheating, and the effect of prior IRSL on the TL signal. Using IRSL measured at 50 °C and a SAR protocol, we then examine the dependence on preheat temperature of equivalent dose (De), laboratory fading rate (g), and the resulting luminescence age, from...... is consistent with a kinetic analysis of sensitivity-corrected IRSL data. The corollary to our observations is that shallow (unstable) traps do not give rise to a significant IRSL signal....

  4. Effects of Preheat on Weldments of NICOP Steel.

    1983-09-01

    percent Nital solution (nitric acid (HNO3) ,* and ethanol (C2HsOH) which revealed the weld area, heat affected zone and base metal. A section 25.2mm (1 inch...electrolyte, consisting of 10% per- cloric acid (HC104 ) and 90% methanal (CH30H) was maintained at a temperature of -450C (-49 0 F). The Polipower was set...Preheated Weidment. N on Non-Preheated Weidment. Figre3. Loaton o McrhadnssTrvese I17 ~.4. .9 G° s s E 43 C 0 CL 44’ 00 Hda *SBUPJQH Figure 4. Comparison

  5. Feed water pre-heater with two steam spaces

    Tratz, H.; Kelp, F.; Netsch, E.

    1976-01-01

    A feed water pre-heater for the two stage heating of feed water by condensing steam, having a low installed height is described, which can be installed in the steam ducts of turbines of large output, as in LWRs in nuclear power stations. The inner steam space is closed on one side by the water vessel, while the tubes of the inner steam space go straight from the water vessel, and the tubes of the outer steam space are bent into a U shape and open out into the water vessel. The two-stage preheater is thus surrounded by feedwater in two ways. (UWI) [de

  6. Gravity waves from tachyonic preheating after hybrid inflation

    Dufaux, Jean-Francois [Instituto de Fisica Teorica UAM/CSIC, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Felder, Gary [Department of Physics, Clark Science Center, Smith College, Northampton, MA 01063 (United States); Kofman, Lev [CITA, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8 (Canada); Navros, Olga, E-mail: jeff.dufaux@uam.es, E-mail: gfelder@email.smith.edu, E-mail: kofman@cita.utoronto.ca, E-mail: navros@email.unc.edu [Department of Mathematics, University of North Carolina Chapel Hill, CB3250 Philips Hall, Chapel Hill, NC 27599 (United States)

    2009-03-15

    We study the stochastic background of gravitational waves produced from preheating in hybrid inflation models. We investigate different dynamical regimes of preheating in these models and we compute the resulting gravity wave spectra using analytical estimates and numerical simulations. We discuss the dependence of the gravity wave frequencies and amplitudes on the various potential parameters. We find that large regions of the parameter space leads to gravity waves that may be observable in upcoming interferometric experiments, including Advanced LIGO, but this generally requires very small coupling constants.

  7. Spring batch essentials

    Rao, P Raja Malleswara

    2015-01-01

    If you are a Java developer with basic knowledge of Spring and some experience in the development of enterprise applications, and want to learn about batch application development in detail, then this book is ideal for you. This book will be perfect as your next step towards building simple yet powerful batch applications on a Java-based platform.

  8. Evaluation of vitrification factors from DWPF's macro-batch 1

    Edwards, T.B.

    2000-01-01

    The Defense Waste Processing Facility (DWPF) is evaluating new sampling and analytical methods that may be used to support future Slurry Mix Evaporator (SME) batch acceptability decisions. This report uses data acquired during DWPF's processing of macro-batch 1 to determine a set of vitrification factors covering several SME and Melter Feed Tank (MFT) batches. Such values are needed for converting the cation measurements derived from the new methods to a ''glass'' basis. The available data from macro-batch 1 were used to examine the stability of these vitrification factors, to estimate their uncertainty over the course of a macro-batch, and to provide a recommendation on the use of a single factor for an entire macro-batch. The report is in response to Technical Task Request HLW/DWPF/TTR-980015

  9. Method for pre-heating lmfbr type reactors

    Yokozawa, Atsushi; Kataoka, Hajime.

    1978-01-01

    Purpose: To enable pre-heating for the inside of the reactor container and the inside of the coolant recycling system with no additional facilities. Method: The coolant recycling system is composed of a heat exchanger, a mechanical pump, a check valve, a flow meter or the like and it is connected in series by way of a pipe line to a reactor container. The mechanical pump is used as a gas recycling device upon pre-heating and it is designed so that a blower such as a fan can be replaced for the impeller of the pump. The inside of the reactor container and the inside of the coolant recycling system is at first filled with an inert gas such as for use with cover gas. Then, nuclear fuels are loaded to attain criticality. Simultaneously, the blower is started and the control rods are operated while cooling the nuclear fuel with the inert gas thus to obtain heat required for pre-heating the pipe line or the like from the nuclear fuels. After the completion of the pre-heating, the liquid metal is charged. (Ikeda, J.)

  10. Constraints on variations in inflaton decay rate from modulated preheating

    Mazumdar, Arindam [Theory Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata-64 (India); Modak, Kamakshya Prasad, E-mail: arindam.mazumdar@saha.ac.in, E-mail: kamakshya.modak@saha.ac.in [Astroparticle Physics and Cosmology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata-64 (India)

    2016-06-01

    Modulated (p)reheating is thought to be an alternative mechanism for producing super-horizon curvature perturbations in CMB. But large non-gaussianity and iso-curvature perturbations produced by this mechanism rule out its acceptability as the sole process responsible for generating CMB perturbations. We explore the situation where CMB perturbations are mostly generated by usual quantum fluctuations of inflaton during inflation, but a modulated coupling constant between inflaton and a secondary scalar affects the preheating process and produces some extra curvature perturbations. If the modulating scalar field is considered to be a dark matter candidate, coupling constant between the fields has to be unnaturally fine tuned in order to keep the local-form non-gaussianity and the amplitude of iso-curvature perturbations within observational limit; otherwise parameters of the models have to be tightly constrained. Those constraints imply that the curvature perturbations generated by modulated preheating should be less than 15% of the total observed CMB perturbations. On the other hand if the modulating scalar field is not a dark matter candidate, parameters of the models could not be constrained, but the constraints on the maximum amount of the curvature perturbations coming from modulated preheating remain valid.

  11. Constraints on variations in inflaton decay rate from modulated preheating

    Mazumdar, Arindam; Modak, Kamakshya Prasad

    2016-01-01

    Modulated (p)reheating is thought to be an alternative mechanism for producing super-horizon curvature perturbations in CMB. But large non-gaussianity and iso-curvature perturbations produced by this mechanism rule out its acceptability as the sole process responsible for generating CMB perturbations. We explore the situation where CMB perturbations are mostly generated by usual quantum fluctuations of inflaton during inflation, but a modulated coupling constant between inflaton and a secondary scalar affects the preheating process and produces some extra curvature perturbations. If the modulating scalar field is considered to be a dark matter candidate, coupling constant between the fields has to be unnaturally fine tuned in order to keep the local-form non-gaussianity and the amplitude of iso-curvature perturbations within observational limit; otherwise parameters of the models have to be tightly constrained. Those constraints imply that the curvature perturbations generated by modulated preheating should be less than 15% of the total observed CMB perturbations. On the other hand if the modulating scalar field is not a dark matter candidate, parameters of the models could not be constrained, but the constraints on the maximum amount of the curvature perturbations coming from modulated preheating remain valid.

  12. Gauge-preheating and the end of axion inflation

    Adshead, Peter; Sfakianakis, Evangelos I. [Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States); Giblin, John T. Jr.; Scully, Timothy R., E-mail: adshead@illinois.edu, E-mail: giblinj@kenyon.edu, E-mail: tscully2@illinois.edu, E-mail: esfaki@illinois.edu [Department of Physics, Kenyon College, 201 North College Rd, Gambier, Ohio 43022 (United States)

    2015-12-01

    We study the onset of the reheating epoch at the end of axion-driven inflation where the axion is coupled to an Abelian, U(1), gauge field via a Chern-Simons interaction term. We focus primarily on m{sup 2φ2} inflation and explore the possibility that preheating can occur for a range of coupling values consistent with recent observations and bounds on the overproduction of primordial black holes. We find that for a wide range of parameters preheating is efficient. In certain cases the inflaton transfers all of its energy to the gauge fields within a few oscillations. In most cases, we find that the gauge fields on sub-horizon scales end preheating in an unpolarized state due to the existence of strong rescattering between the inflaton and gauge-field modes. We also present a preliminary study of an axion monodromy model coupled to U(1) gauge fields, seeing a similarly efficient preheating behavior as well as indications that the coupling strength has an effect on the creation of oscillons.

  13. Gauge-preheating and the end of axion inflation

    Adshead, Peter; Sfakianakis, Evangelos I.; Giblin, John T. Jr.; Scully, Timothy R.

    2015-01-01

    We study the onset of the reheating epoch at the end of axion-driven inflation where the axion is coupled to an Abelian, U(1), gauge field via a Chern-Simons interaction term. We focus primarily on m 2φ2 inflation and explore the possibility that preheating can occur for a range of coupling values consistent with recent observations and bounds on the overproduction of primordial black holes. We find that for a wide range of parameters preheating is efficient. In certain cases the inflaton transfers all of its energy to the gauge fields within a few oscillations. In most cases, we find that the gauge fields on sub-horizon scales end preheating in an unpolarized state due to the existence of strong rescattering between the inflaton and gauge-field modes. We also present a preliminary study of an axion monodromy model coupled to U(1) gauge fields, seeing a similarly efficient preheating behavior as well as indications that the coupling strength has an effect on the creation of oscillons

  14. Theory and numerics of gravitational waves from preheating after inflation

    Dufaux, Jean-Francois; Kofman, Lev; Bergman, Amanda; Felder, Gary; Uzan, Jean-Philippe

    2007-01-01

    Preheating after inflation involves large, time-dependent field inhomogeneities, which act as a classical source of gravitational radiation. The resulting spectrum might be probed by direct detection experiments if inflation occurs at a low enough energy scale. In this paper, we develop a theory and algorithm to calculate, analytically and numerically, the spectrum of energy density in gravitational waves produced from an inhomogeneous background of stochastic scalar fields in an expanding universe. We derive some generic analytical results for the emission of gravity waves by stochastic media of random fields, which can test the validity/accuracy of numerical calculations. We contrast our method with other numerical methods in the literature, and then we apply it to preheating after chaotic inflation. In this case, we are able to check analytically our numerical results, which differ significantly from previous works. We discuss how the gravity-wave spectrum builds up with time and find that the amplitude and the frequency of its peak depend in a relatively simple way on the characteristic spatial scale amplified during preheating. We then estimate the peak frequency and amplitude of the spectrum produced in two models of preheating after hybrid inflation, which for some parameters may be relevant for gravity-wave interferometric experiments

  15. SPS batch spacing optimisation

    Velotti, F M; Carlier, E; Goddard, B; Kain, V; Kotzian, G

    2017-01-01

    Until 2015, the LHC filling schemes used the batch spac-ing as specified in the LHC design report. The maximumnumber of bunches injectable in the LHC directly dependson the batch spacing at injection in the SPS and hence onthe MKP rise time.As part of the LHC Injectors Upgrade project for LHCheavy ions, a reduction of the batch spacing is needed. In thisdirection, studies to approach the MKP design rise time of150ns(2-98%) have been carried out. These measurementsgave clear indications that such optimisation, and beyond,could be done also for higher injection momentum beams,where the additional slower MKP (MKP-L) is needed.After the successful results from 2015 SPS batch spacingoptimisation for the Pb-Pb run [1], the same concept wasthought to be used also for proton beams. In fact, thanksto the SPS transverse feed back, it was already observedthat lower batch spacing than the design one (225ns) couldbe achieved. For the 2016 p-Pb run, a batch spacing of200nsfor the proton beam with100nsbunch spacing wasreque...

  16. DWPF GLASS BEADS AND GLASS FRIT TRANSPORT DEMONSTRATION

    Adamson, D; Bradley Pickenheim, B

    2008-11-24

    DWPF is considering replacing irregularly shaped glass frit with spherical glass beads in the Slurry Mix Evaporator (SME) process to decrease the yield stress of the melter feed (a non-Newtonian Bingham Plastic). Pilot-scale testing was conducted on spherical glass beads and glass frit to determine how well the glass beads would transfer when compared to the glass frit. Process Engineering Development designed and constructed the test apparatus to aid in the understanding and impacts that spherical glass beads may have on the existing DWPF Frit Transfer System. Testing was conducted to determine if the lines would plug with the glass beads and the glass frit slurry and what is required to unplug the lines. The flow loop consisted of vertical and horizontal runs of clear PVC piping, similar in geometry to the existing system. Two different batches of glass slurry were tested: a batch of 50 wt% spherical glass beads and a batch of 50 wt% glass frit in process water. No chemicals such as formic acid was used in slurry, only water and glass formers. The glass beads used for this testing were commercially available borosilicate glass of mesh size -100+200. The glass frit was Frit 418 obtained from DWPF and is nominally -45+200 mesh. The spherical glass beads did not have a negative impact on the frit transfer system. The transferring of the spherical glass beads was much easier than the glass frit. It was difficult to create a plug with glass bead slurry in the pilot transfer system. When a small plug occurred from setting overnight with the spherical glass beads, the plug was easy to displace using only the pump. In the case of creating a man made plug in a vertical line, by filling the line with spherical glass beads and allowing the slurry to settle for days, the plug was easy to remove by using flush water. The glass frit proved to be much more difficult to transfer when compared to the spherical glass beads. The glass frit impacted the transfer system to the point

  17. DWPF GLASS BEADS AND GLASS FRIT TRANSPORT DEMONSTRATION

    Adamson, D.; Pickenheim, Bradley

    2008-01-01

    DWPF is considering replacing irregularly shaped glass frit with spherical glass beads in the Slurry Mix Evaporator (SME) process to decrease the yield stress of the melter feed (a non-Newtonian Bingham Plastic). Pilot-scale testing was conducted on spherical glass beads and glass frit to determine how well the glass beads would transfer when compared to the glass frit. Process Engineering Development designed and constructed the test apparatus to aid in the understanding and impacts that spherical glass beads may have on the existing DWPF Frit Transfer System. Testing was conducted to determine if the lines would plug with the glass beads and the glass frit slurry and what is required to unplug the lines. The flow loop consisted of vertical and horizontal runs of clear PVC piping, similar in geometry to the existing system. Two different batches of glass slurry were tested: a batch of 50 wt% spherical glass beads and a batch of 50 wt% glass frit in process water. No chemicals such as formic acid was used in slurry, only water and glass formers. The glass beads used for this testing were commercially available borosilicate glass of mesh size -100+200. The glass frit was Frit 418 obtained from DWPF and is nominally -45+200 mesh. The spherical glass beads did not have a negative impact on the frit transfer system. The transferring of the spherical glass beads was much easier than the glass frit. It was difficult to create a plug with glass bead slurry in the pilot transfer system. When a small plug occurred from setting overnight with the spherical glass beads, the plug was easy to displace using only the pump. In the case of creating a man made plug in a vertical line, by filling the line with spherical glass beads and allowing the slurry to settle for days, the plug was easy to remove by using flush water. The glass frit proved to be much more difficult to transfer when compared to the spherical glass beads. The glass frit impacted the transfer system to the point

  18. On the generation of a non-gaussian curvature perturbation during preheating

    Kohri, Kazunori; Lyth, David H. [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom); Valenzuela-Toledo, Cesar A., E-mail: k.kohri@lancaster.ac.uk, E-mail: d.lyth@lancaster.ac.uk, E-mail: cavalto@ciencias.uis.edu.co [Escuela de Física, Universidad Industrial de Santander, Ciudad Universitaria, Bucaramanga (Colombia)

    2010-02-01

    The perturbation of a light field might affect preheating and hence generate a contribution to the spectrum and non-gaussianity of the curvature perturbation ζ. The field might appear directly in the preheating model (curvaton-type preheating) or indirectly through its effect on a mass or coupling (modulated preheating). We give general expressions for ζ based on the δN formula, and apply them to the cases of quadratic and quartic chaotic inflation. For the quadratic case, curvaton-type preheating is ineffective in contributing to ζ, but modulated preheating can be effective. For quartic inflation, curvaton-type preheating may be effective but the usual δN formalism has to be modified. We see under what circumstances the recent numerical simulation of Bond et al. [0903.3407] may be enough to provide a rough estimate for this case.

  19. On the generation of a non-gaussian curvature perturbation during preheating

    Kohri, Kazunori; Lyth, David H.; Valenzuela-Toledo, Cesar A.

    2010-01-01

    The perturbation of a light field might affect preheating and hence generate a contribution to the spectrum and non-gaussianity of the curvature perturbation ζ. The field might appear directly in the preheating model (curvaton-type preheating) or indirectly through its effect on a mass or coupling (modulated preheating). We give general expressions for ζ based on the δN formula, and apply them to the cases of quadratic and quartic chaotic inflation. For the quadratic case, curvaton-type preheating is ineffective in contributing to ζ, but modulated preheating can be effective. For quartic inflation, curvaton-type preheating may be effective but the usual δN formalism has to be modified. We see under what circumstances the recent numerical simulation of Bond et al. [0903.3407] may be enough to provide a rough estimate for this case

  20. Production of gravitational waves during preheating with nonminimal coupling

    Fu, Chengjie; Wu, Puxun; Yu, Hongwei

    2018-04-01

    We study the preheating and the in-process production of gravitational waves (GWs) after inflation in which the inflaton is nonminimally coupled to the curvature in a self-interacting quartic potential with the method of lattice simulation. We find that the nonminimal coupling enhances the amplitude of the density spectrum of inflaton quanta, and as a result, the peak value of the GW spectrum generated during preheating is enhanced as well and might reach the limit of detection in future GW experiments. The peaks of the GW spectrum not only exhibit distinctive characteristics as compared to those of minimally coupled inflaton potentials but also imprint information on the nonminimal coupling and the parametric resonance, and thus the detection of these peaks in the future will provide us a new avenue to reveal the physics of the early universe.

  1. Thermographic study of the preheating plugs in diesel engines

    Royo Pastor, Rafael; Albertos Arranz, M.A.; CÁRCEL CUBAS, JUAN ANTONIO; Payá Herrero, Jorge

    2012-01-01

    The use of direct injection diesel engines has been widely applied during the past ten years. In such engines, the preheating plugs are a key element which has a significant contribution in the pollutant emissions. In this paper, two different plug designs from Renault are analyzed. The new plug reduces substantially the required electrical consumption. Nevertheless, the pollutant emissions are higher (fundamentally CO and HCs) and hereby a thorough analysis is required to underst...

  2. DEFROST: a new code for simulating preheating after inflation

    Frolov, Andrei V

    2008-01-01

    At the end of inflation, dynamical instability can rapidly deposit the energy of homogeneous cold inflaton into excitations of other fields. This process, known as preheating, is rather violent, inhomogeneous and non-linear, and has to be studied numerically. This paper presents a new code for simulating scalar field dynamics in an expanding universe written for that purpose. Compared to available alternatives, it significantly improves both the speed and the accuracy of calculations, and is fully instrumented for 3D visualization. We reproduce previously published results on preheating in simple chaotic inflation models, and further investigate non-linear dynamics of the inflaton decay. Surprisingly, we find that the fields do not 'want' to thermalize in quite the way that one would think. Instead of directly reaching equilibrium, the evolution appears to be stuck in a rather simple but quite inhomogeneous state. In particular, a one-point distribution function of total energy density appears to be universal among various two-field preheating models, and is exceedingly well described by a log-normal distribution. It is tempting to attribute this state to scalar field turbulence

  3. CFD modeling of fouling in crude oil pre-heaters

    Bayat, Mahmoud; Aminian, Javad; Bazmi, Mansour; Shahhosseini, Shahrokh; Sharifi, Khashayar

    2012-01-01

    Highlights: ► A conceptual CFD-based model to predict fouling in industrial crude oil pre-heaters. ► Tracing fouling formation in the induction and developing continuation periods. ► Effect of chemical components, shell-side HTC and turbulent flow on the fouling rate. - Abstract: In this study, a conceptual procedure based on the computational fluid dynamic (CFD) technique has been developed to predict fouling rate in an industrial crude oil pre-heater. According to the developed CFD concept crude oil was assumed to be composed of three pseudo-components comprising of petroleum, asphaltene and salt. The binary diffusion coefficients were appropriately categorized into five different groups. The species transport model was applied to simulate the mixing and transport of chemical species. The possibility of adherence of reaction products to the wall was taken into account by applying a high viscosity for the products in competition with the shear stress on the wall. Results showed a reasonable agreement between the model predictions and the plant data. The CFD model could be applied to new operating conditions to investigate the details of the crude oil fouling in the industrial pre-heaters.

  4. Heuristics for batching and sequencing in batch processing machines

    Chuda Basnet

    2016-12-01

    Full Text Available In this paper, we discuss the “batch processing” problem, where there are multiple jobs to be processed in flow shops. These jobs can however be formed into batches and the number of jobs in a batch is limited by the capacity of the processing machines to accommodate the jobs. The processing time required by a batch in a machine is determined by the greatest processing time of the jobs included in the batch. Thus, the batch processing problem is a mix of batching and sequencing – the jobs need to be grouped into distinct batches, the batches then need to be sequenced through the flow shop. We apply certain newly developed heuristics to the problem and present computational results. The contributions of this paper are deriving a lower bound, and the heuristics developed and tested in this paper.

  5. Study on the preheating duration of Cu{sub 2}SnS{sub 3} thin films using RF magnetron sputtering technique for photovoltaics

    Dong, Yuchen; He, Jun; Li, Xinran; Chen, Ye; Sun, Lin, E-mail: lsun@ee.ecnu.edu.cn; Yang, Pingxiong; Chu, Junhao

    2016-04-25

    Cu{sub 2}SnS{sub 3} (CTS) thin films are prepared by sulfurization the stacked metallic precursors deposited by raido-frequency magnetron sputtering method on molybdenum-coated soda lime glass substrates. The details of sulfurization process and the effect of preheating duration on the properties of CTS thin films have been investigated. It is found that the content of element tin strongly depend on the preheating duration. X-ray diffraction patterns identify that the CTS thin films exhibit the monoclinic structure. Raman scattering spectra make a further confirmation for the crystal structure. Fourier transform infrared reflectance spectroscopy (FTIR) is first used to study the properties of CTS thin films. The assigned active modes in Raman scattering spectra is consistent with the analysis in FTIR. Morphology analysis reveals long preheating duration would make the quality of films deteriorate. The thin film solar cell (TFSC) fabricated using the CTS absorber layer synthesized at preheating duration of 15 min shows that a power conversion efficiency up to 0.76% for a 0.19 cm{sup 2} area. The electrical characterization of CTS TFSC is first studied by electrochemical impedance spectroscopy, which implies the existence of MoS{sub x} and defects in the CTS/CdS interface. - Highlights: • CTS thin films and solar cells prepared by RF magnetron sputtering. • Preheating duration is a critical way to remain the Sn content in CTS thin film. • XRD, Raman, FTIR and XPS confirmed the single phase of CTS thin film. • The device characterization of CTS solar cell has been systematically investigated.

  6. Sludge Batch Variability Study With Frit 418

    Johnson, F.; Edwards, T.

    2010-01-01

    The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO 2 resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass regardless of

  7. Prunus dulcis, Batch

    STORAGESEVER

    2010-06-07

    Jun 7, 2010 ... almond (Prunus dulcis, Batch) genotypes as revealed by PCR analysis. Yavar Sharafi1*, Jafar Hajilou1, Seyed AbolGhasem Mohammadi2, Mohammad Reza Dadpour1 and Sadollah Eskandari3. 1Department of Horticulture, Faculty of Agriculture, University of Tabriz, Tabriz, 5166614766, Iran.

  8. Preheating Water In The Covers Of Solar Water Heaters

    Bhandari, Pradeep

    1995-01-01

    Solar water heaters that include glass covers over absorber plates redesigned to increase efficiencies according to proposal. Redesign includes modification of single-layer glass cover into double-layer glass cover and addition of plumbing so cool water to be heated made to flow between layers of cover before entering absorber plate.

  9. Regenerative heat exchanger for cowper combustion air preheating

    Molenaar, R.; Otterbach, G.

    1986-01-13

    The waste gas leaving cowper units at a temperature of 200/sup 0/C to 300/sup 0/C was previously discharged unused into the atmosphere. By providing a suitable heat exchanger, the heat content of the waste gas can be used to preheat the combustion agents of cowpers to an extent allowing both to increase the efficiency of cowpers and to decrease the amount of rich gas required. The operating results confirm to a large extent the theoretical assumptions and calculations. One may therefore expect the entire investment to have been fully redeemed in a little more than two years. (orig.).

  10. Bruce NGS A Unit 4 preheater divider plate failure

    Landridge, M.; McInnes, D.

    1995-01-01

    On May 19, 1995, without any prior operational indications, Bruce A discovered preheater divider plate damage in Unit 4 that had the potential to have a major impact on the continued safe operation of the station. Further investigations indicated that Unit 4 may have been operating with this damage for as long as ten years. In the two months following the discovery, Bruce A has procured and replaced the 4 divider plates, located most of the missing pieces, retrieved pieces from the PHT system, investigated historical operational information, performed detailed analytical investigations, investigated root cause, performed in-situ and mock-up testing, updated operational procedures and installed DP monitoring equipment

  11. Combustion measurements in an industrial gas-fired flat-glass furnace

    Newbold, J; Webb, B W; McQuay, M Q [Brigham Young Univ., Provo, UT (United States). Mechanical Engineering Dept.; Huber, A M [Ford Motor Co., Glass Div., Dearborn, MI (United States)

    1997-06-01

    Profiles of velocity, species concentration (O{sub 2}, CO and CO{sub 2}), wall incident radiative heat flux and temperature are reported in the combustion space of a regenerative, side-port, 550t/day, gas-fired flat-glass furnace. A region exists of fast-moving gases near the glass, with axial velocity components exceeding 20 m s{sup -1}, and a large recirculation zone near the crown. Temperatures as high as 1985 K in the flame and as low as 1750 K in the recirculation zone are reported. A region of intense reaction is observed near the glass, with large concentration gradients and incomplete combustion even in the tail of the flame. Local incident radiant fluxes on the crown were nearly uniform spatially at a level of 680 kW m{sup -2}. In the portnecks, flat inlet velocity profiles were measured with a magnitude of approximately 11 m s{sup -1}. Significant variations were observed in the exhaust profiles of most measured variables. Large errors in exhaust mass balance suggest a complex, three-dimensional flow with recirculation zones along the side walls of the portnecks. A nominal preheat air temperature of 1420 k and a variation of exhaust temperatures between 1630 K and 1835 K were noted. O{sub 2} concentrations as high as 8.4% were measured at the exit, suggesting a bypass of oxygen-rich flow around the flame. CO{sub 2} concentrations were the highest near the batch, where the glass reactions are the most intense. (Author)

  12. Modelling of Batch Process Operations

    Abdul Samad, Noor Asma Fazli; Cameron, Ian; Gani, Rafiqul

    2011-01-01

    Here a batch cooling crystalliser is modelled and simulated as is a batch distillation system. In the batch crystalliser four operational modes of the crystalliser are considered, namely: initial cooling, nucleation, crystal growth and product removal. A model generation procedure is shown that s...

  13. Fresh fuel pre-heating device in reactor facility

    Samejima, Asakuni.

    1988-01-01

    Purpose: To simplify the structure of a fresh nuclear fuel pre-heating device and improve the reliability to gas supply. Constitution: Fresh fuels taken out from a fresh fuel stredge rack and contained in a fuel strage pipe of a fuel transportation cask are pre-heated at the pre-stage of transfer by sending heating gases from the outside. Gas outlet pipes of the device are led out from the lower portion of the strage pipe, disposed side by side at the top of the strage pipe and opened upwardly. Further, gas supply pipes are connected to the inside of a movable guiding cylinder on the side of the floor surface and the opening end of return pipes are opposed to the exit opening end of the strage pipe. In such a constitution, a gas recycling loop can be formed between the strage pipe and the gas heating device by way of the movable guiding cylinder only by the operation of combining the fuel strage pipe of the transportation cask and the movable guiding pipe disposed on the side of the floor surface. Thus, the coupling structure is facilitated, the connection operation can surely be conducted to improve the reliability as compared with the conventional case. (Horiuchi, T.)

  14. Parameter optimization through performance analysis of model based control of a batch heat treatment furnace with low NO x radiant tube burner

    Tiwari, Manish Kumar; Mukhopadhyay, Achintya; Sanyal, Dipankar

    2005-01-01

    A model based control structure for heat treating a 0.5% C steel slab in a batch furnace with low NO x radiant tube burner is designed and tested for performance to yield optimal parameter values using the model developed in the companion paper. Combustion is considered in a highly preheated and product gas diluted mode. Controlled combustion with a proposed arrangement for preheating and diluting the air by recirculating the exhaust gas that can be retrofitted with an existing burner yields satisfactory performance and emission characteristics. Finally, the effect of variable property considerations are presented and critically analyzed

  15. Flat plate solar collector for water pre-heating using concentrated solar power (CSP)

    Peris, Leonard Sunny; Shekh, Md. Al Amin; Sarker, Imran

    2017-12-01

    Numerous attempt and experimental conduction on different methods to harness energy from renewable sources are being conducted. This study is a contribution to the purpose of harnessing solar energy as a renewable source by using flat plate solar collector medium to preheat water. Basic theory of solar radiation and heat convection in water (working fluid) has been combined with heat conduction process by using copper tubes and aluminum absorber plate in a closed conduit, covered with a glazed through glass medium. By this experimental conduction, a temperature elevation of 35°C in 10 minutes duration which is of 61.58% efficiency range (maximum) has been achieved. The obtained data and experimental findings are validated with the theoretical formulation and an experimental demonstration model. A cost effective and simple form of heat energy extraction method for space heating/power generation has been thoroughly discussed with possible industrial implementation possibilities. Under-developed and developing countries can take this work as an illustration for renewable energy utilization for sustainable energy prospect. Also a full structure based data to derive concentrated solar energy in any geographical location of Bangladesh has been outlined in this study. These research findings can contribute to a large extent for setting up any solar based power plant in Bangladesh irrespective of its installation type.

  16. Effects of substrate preheating during direct energy deposition on microstructure, hardness, tensile strength, and notch toughness

    Baek, Gyeong Yun; Lee, Ki Yong; Park, Sang Hu; Shim, Do Sik

    2017-11-01

    This study examined the effects of substrate preheating for the hardfacing of cold-press dies using the high-speed tool steel AISI M4. The preheating of the substrate is a widely used technique for reducing the degree of thermal deformation and preventing crack formation. We investigated the changes in the metallurgical and mechanical properties of the high-speed tool steel M4 deposited on an AISI D2 substrate with changes in the substrate preheating temperature. Five preheating temperatures (100-500 °C; interval of 100 °C) were selected, and the changes in the temperature of the substrate during deposition were observed. As the preheating temperature of the substrate was increased, the temperature gradient between the melting layer and the substrate decreased; this prevented the formation of internal cracks, owing to thermal stress relief. Field-emission scanning electron microscopy showed that a dendritic structure was formed at the interface between the deposited layer and the substrate while a cellular microstructure was formed in the deposited layer. As the preheating temperature was increased, the sizes of the cells and precipitated carbides also increased. Furthermore, the hardness increased slightly while the strength and toughness decreased. Moreover, the tensile and impact properties deteriorated rapidly at excessively high preheating temperatures (greater than 500 °C). The results of this study can be used as preheating criteria for achieving the desired mechanical properties during the hardfacing of dies and molds.

  17. Reheating the D-brane universe via instant preheating

    Panda, Sudhakar; Sami, M.; Thongkool, I.

    2010-01-01

    We investigate a possibility of reheating in a scenario of D-brane inflation in a warped deformed conifold background which includes perturbative corrections to throat geometry sourced by a chiral operator of dimension 3/2 in the conformal field theory. The effective D-brane potential, in this case, belongs to the class of nonoscillatory models of inflation for which the conventional reheating mechanism does not work. We find that gravitational particle production is inefficient and leads to reheating temperature of the order of 10 8 GeV. We show that instant preheating is quite suitable to the present scenario and can easily reheat the universe to a temperature which is higher by about 3 orders of magnitude than its counterpart associated with gravitational particle production. The reheating temperature is shown to be insensitive to a particular choice of inflationary parameters suitable to observations.

  18. Optimization of heat-liberating batches for ash residue stabilization

    Karlina, O.K.; Varlackova, G.A.; Ojovan, M.I.; Tivansky, V.M.; Dmitriev, S.A.

    1999-01-01

    The ash residue obtained after incineration of solid radioactive waste is a dusting poly-dispersed powder like material that contains radioactive nuclides ( 137 Cs, 90 Sr, 239 Pu, hor ( ellipsis)). Specific radioactivity of the ash can be about 10 5 --10 7 Bq/kg. In order to dispose of the ash, residue shall be stabilized by producing a monolith material. The ash residue can be either vitrified or stabilized into a ceramic matrix. For this purpose the ash residue is mixed with fluxing agents followed by melting of obtained composition in the different type melters. As a rule this requires both significant energy consumption and complex melting equipment. A stabilization technology of ash residue was proposed recently by using heat liberating batches-compositions with redox properties. The ash residue is melted due to exothermic chemical reactions in the mixture with heat-liberating batch that occur with considerable release of heat. Stabilization method has three stages: (1) preparation of a mixture of heating batch and ash residue with or without glass forming batch (frit); (2) ignition and combustion of mixed composition; (3) cooling (quenching) of obtained vitreous material. Combustion of mixed composition occurs in the form of propagation of reacting wave. The heat released during exothermic chemical reactions provides melting of ash residue components and production of glass-like phase. The final product consists of a glass like matrix with embedded crystalline inclusions of infusible ash residue components

  19. Progressing batch hydrolysis process

    Wright, J.D.

    1985-01-10

    A progressive batch hydrolysis process is disclosed for producing sugar from a lignocellulosic feedstock. It comprises passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with feed stock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feed stock to glucose. The cooled dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, serially fed through a plurality of pre-hydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose. The dilute acid stream containing glucose is cooled after it exits the last prehydrolysis reactor.

  20. Powertrain preheating system of tracked hybrid electric vehicle in cold weather

    Wang, Rui; Wang, Yichun; Feng, Chaoqing; Zhang, Xilong

    2015-01-01

    In order to make sure that the heavy duty tracked vehicle can work in various conditions, especially severe cold weather, preheating system of powertrain should be adopted, and a novel preheating system is presented for the tracked hybrid electric vehicle (HEV) in which heat is generated by the low-speed drive motor. The new preheating system can meet the need of cold start without adding any additional device. The characteristic of heat generation by motor is tested when the rotor of motor is rotated in very low speed. The heat loss from power cabin to external environment has been simulated, and the relevant test has been done to verify the simulation results. Combining the characteristic of heat generation and heat loss situation about preheating system, the heat transfer model of preheating system was implemented by MATLAB. The total energy required for preheating in different ambient temperature was calculated by this model. The results showed that: the minimum heating power was 70 kW and energy required was about 180 MJ when the HEV worked in −46 °C. If lithium ferrous phosphate (LFP) battery was used in power system, the minimum battery capacity is about 290 A h. - Highlights: • A novel preheating method was proposed for heavy duty tracked HEV. • Thermal energy in preheating system is produced by the PMSM in driving system. • This method can achieve preheating target by its own components without any adding. • Analyzing low temperature performance of power battery and select its capacity.

  1. Measurement of preheat in aluminium target in indirect drive using the SGIII prototype facilities

    Zhang, C; Zheng, J; Wang, Z B; Liu, H; Peng, X S; Wang, F; Ding, Y K

    2016-01-01

    The velocity interferometer system for any reflector (VISAR) is used to demonstrate preheat effect in aluminium in indirect drive. The rear surface motion prior to shock front was observed and compared with a multi-group calculation. By properly adjusting the hard x-ray portion of the radiation source, the calculated rear surface motion fits well with the experimental results, which gives us confidence to predict the preheated temperature of the sample by hard x-rays. Further, the effect of hohlraum geometry is compared and discussed experimentally. The result suggests gas-filled hohlraum or hohlraum with low Z substrates should be considered to further reduce preheating. (paper)

  2. Analysis of pre-heated fuel combustion and heat-emission dynamics in a diesel engine

    Plotnikov, S. A.; Kartashevich, A. N.; Buzikov, S. V.

    2018-01-01

    The article explores the feasibility of diesel fuel pre-heating. The research goal was to obtain and analyze the performance diagrams of a diesel engine fed with pre-heated fuel. The engine was tested in two modes: at rated RPMs and at maximum torque. To process the diagrams the authors used technique developed by the Central Diesel Research Institute (CDRI). The diesel engine’s heat emission curves were obtained. The authors concluded that fuel pre-heating shortened the initial phase of the combustion process and moderated the loads, thus making it possible to boost a diesel engine’s mean effective pressure.

  3. Effect of pre-heat treatment on a Fischer-Tropsch iron catalyst

    Rao, K.R.P.M.; Huggins, F.E.; Ganguly, B.; Mahajan, V.; Huffman, G.P.; Davis, B.; O'Brien, R.J.; Xu Liguang; Rao, V.U.S.

    1994-01-01

    Moessbauer spectroscopy was used to investigate the effect of heating the Fischer-Tropsch catalyst 100 Fe/5 Cu/4.2 K/24 SiO 2 in two different atmospheres while ramping the temperature of the catalyst from room temperature to 280 C in 5.5 h prior to pretreatment of the catalyst. Preheating in H 2 /CO = 0.7 gave rise to an iron (Fe 2+ ) silicate, while preheating in helium resulted in the formation of ε'-carbide Fe 2.2 C. Iron oxides and χ-carbide Fe 5 C 2 were also formed in both preheat treatments. (orig.)

  4. Calculation and design of natural gas preheater equipments. Berechnung und Auslegung von Erdgas-Vorwaermeanlagen

    Fasold, H G [Ruhrgas AG, Essen (Germany); Wahle, H N [Ruhrgas AG, Essen (Germany)

    1994-04-01

    A greatly simplified model of a regulating station - consisting of the station components ''preheater'' and ''control unit'' - is used for the calculation and design of natural gas preheating plants. It is hereby possible to calculate the Joule-Thomson effect which occurs on the expansion of natural gas in the controller, the resulting drop in temperature and the thermal output required to compensate this which is to be supplied to the gas flow by the preheating plant. The calculation method and procedure are explained using a programming flowchart. The computational model presented was converted into a personal computer program, whose functioning is elucidated using a numerical example. (orig.)

  5. arXiv Gravitational wave production from preheating -- parameter dependence

    Figueroa, Daniel G.

    2017-10-31

    Parametric resonance is among the most efficient phenomena generating gravitational waves (GWs) in the early Universe. The dynamics of parametric resonance, and hence of the GWs, depend exclusively on the resonance parameter q. The latter is determined by the properties of each scenario: the initial amplitude and potential curvature of the oscillating field, and its coupling to other species. Previous works have only studied the GW production for fixed value(s) of q. We present an analytical derivation of the GW amplitude dependence on q, valid for any scenario, which we confront against numerical results. By running lattice simulations in an expanding grid, we study for a wide range of q values, the production of GWs in post-inflationary preheating scenarios driven by parametric resonance. We present simple fits for the final amplitude and position of the local maxima in the GW spectrum. Our parametrization allows to predict the location and amplitude of the GW background today, for an arbitrary q. The GW si...

  6. Modeling of evaporation processes in glass melting furnaces

    Limpt, van J.A.C.

    2007-01-01

    The majority of glass furnaces worldwide, apply fossil fuel combustion to transfer heat directly by radiation from the combustion processes to the melting batch and glass melt. During these high temperature melting processes, some glass components, such as: sodium, potassium, boron and lead species

  7. Experimental Investigation of Flow Resistance in a Coal Mine Ventilation Air Methane Preheated Catalytic Oxidation Reactor

    Bin Zheng

    2015-01-01

    Full Text Available This paper reports the results of experimental investigation of flow resistance in a coal mine ventilation air methane preheated catalytic oxidation reactor. The experimental system was installed at the Energy Research Institute of Shandong University of Technology. The system has been used to investigate the effects of flow rate (200 Nm3/h to 1000 Nm3/h and catalytic oxidation bed average temperature (20°C to 560°C within the preheated catalytic oxidation reactor. The pressure drop and resistance proportion of catalytic oxidation bed, the heat exchanger preheating section, and the heat exchanger flue gas section were measured. In addition, based on a large number of experimental data, the empirical equations of flow resistance are obtained by the least square method. It can also be used in deriving much needed data for preheated catalytic oxidation designs when employed in industry.

  8. Preheat-induced signal enhancement in the infrared stimulated luminescence of young and bleached sediment samples

    Richardson, C.A.

    2000-01-01

    Natural and laboratory bleached surface and young samples of potassium feldspar sand separates and polymineral silt had their infrared stimulated luminescence (IRSL) signal measured before and after preheating at 220 deg. C for 10 min or 160 deg. C for 16 h. For both preheats, the laboratory bleached sand samples underwent a signal enhancement which was stable with laboratory storage. The youngest samples also showed natural signal enhancement. The silt sample showed no recuperation of bleached signal on preheating, but some in the natural signal. A range of filtered bleaches was applied to one surface sand sample. Signal levels before and after preheating were reduced by filtering out the UV from the bleaching spectrum. The unfiltered bleach, however, most closely reproduced the behaviour of the natural sample

  9. Kubernetes as a batch scheduler

    Souza, Clenimar; Brito Da Rocha, Ricardo

    2017-01-01

    This project aims at executing a CERN batch use case using Kubernetes, in order to figure out what are the advantages and disadvantages, as well as the functionality that can be replicated or is missing. The reference for the batch system is the CERN Batch System, which uses HTCondor. Another goal of this project is to evaluate the current status of federated resources in Kubernetes, in comparison to the single-cluster API resources. Finally, the last goal of this project is to implement buil...

  10. Microwave pre-heating of natural rubber using a rectangular wave guide (MODE: TE10

    Doo-ngam, N.

    2007-11-01

    Full Text Available This paper presents an application of microwave radiation for pre-heating of natural rubbercompounding with various sulphur contents. The natural rubber-compounding was pre-heated by microwave radiation using a rectangular wave guide system (MODE: TE10 operating at frequency of 2.45 GHz in which the power can vary from 0 to 1500 W. In the present work, the influence of power input, sample thickness, and sulphur content were examined after applying microwave radiation to the rubber samples. Results are discussed regarding the thermal properties, 3-D network, dielectric properties and chemical structures. From the result, firstly, it was found that microwave radiation can be applied to pre-heating natural rubber-compounding before the vulcanization process. Secondly, microwave radiation was very useful for pre-heating natural rubber-compounding that has a thickness greater than 5mm. Thirdly, crosslinking in natural rubber-compounding may occurs after pre-heating by microwave radiation though Fourier Transform Infrared Spectroscopy(FTIR. Finally, there a little effect of sulphur content on temperature profiles after applying microwave radiation to the natural rubber-compounding. Moreover, natural rubber-compounding without carbon black showed a lower heat absorption compared with natural rubbercompounding filled carbon black. This is due to the difference in dielectric loss factor. This preliminary result will be useful information in terms of microwave radiation for pre-heating natural rubber-compounding and rubber processing in industry.

  11. Optimal Substrate Preheating Model for Thermal Spray Deposition of Thermosets onto Polymer Matrix Composites

    Ivosevic, M.; Knight, R.; Kalidindi, S. R.; Palmese, G. R.; Tsurikov, A.; Sutter, J. K.

    2003-01-01

    High velocity oxy-fuel (HVOF) sprayed, functionally graded polyimide/WC-Co composite coatings on polymer matrix composites (PMC's) are being investigated for applications in turbine engine technologies. This requires that the polyimide, used as the matrix material, be fully crosslinked during deposition in order to maximize its engineering properties. The rapid heating and cooling nature of the HVOF spray process and the high heat flux through the coating into the substrate typically do not allow sufficient time at temperature for curing of the thermoset. It was hypothesized that external substrate preheating might enhance the deposition behavior and curing reaction during the thermal spraying of polyimide thermosets. A simple analytical process model for the deposition of thermosetting polyimide onto polymer matrix composites by HVOF thermal spray technology has been developed. The model incorporates various heat transfer mechanisms and enables surface temperature profiles of the coating to be simulated, primarily as a function of substrate preheating temperature. Four cases were modeled: (i) no substrate preheating; (ii) substrates electrically preheated from the rear; (iii) substrates preheated by hot air from the front face; and (iv) substrates electrically preheated from the rear and by hot air from the front.

  12. Data-driven batch schuduling

    Bent, John [Los Alamos National Laboratory; Denehy, Tim [GOOGLE; Arpaci - Dusseau, Remzi [UNIV OF WISCONSIN; Livny, Miron [UNIV OF WISCONSIN; Arpaci - Dusseau, Andrea C [NON LANL

    2009-01-01

    In this paper, we develop data-driven strategies for batch computing schedulers. Current CPU-centric batch schedulers ignore the data needs within workloads and execute them by linking them transparently and directly to their needed data. When scheduled on remote computational resources, this elegant solution of direct data access can incur an order of magnitude performance penalty for data-intensive workloads. Adding data-awareness to batch schedulers allows a careful coordination of data and CPU allocation thereby reducing the cost of remote execution. We offer here new techniques by which batch schedulers can become data-driven. Such systems can use our analytical predictive models to select one of the four data-driven scheduling policies that we have created. Through simulation, we demonstrate the accuracy of our predictive models and show how they can reduce time to completion for some workloads by as much as 80%.

  13. Ultraviolet optical absorptions of semiconducting copper phosphate glasses

    Bae, Byeong-Soo; Weinberg, Michael C.

    1993-01-01

    Results are presented of a quantitative investigation of the change in UV optical absorption in semiconducting copper phosphate glasses with batch compositions of 40, 50, and 55 percent CuO, as a function of the Cu(2+)/Cu(total) ratio in the glasses for each glass composition. It was found that optical energy gap, E(opt), of copper phosphate glass is a function of both glass composition and Cu(2+)/Cu(total) ratio in the glass. E(opt) increases as the CuO content for fixed Cu(2+)/Cu(total) ratio and the Cu(2+)/Cu(total) ratio for fixed glass composition are reduced.

  14. Control of radioactive waste-glass melters

    Bickford, D.F.; Smith, P.K.; Hrma, P.; Bowan, B.W.

    1987-01-01

    Radioactive waste-glass melters require physical control limits and redox control of glass to assure continuous operation, and maximize production rates. Typical waste-glass melter operating conditions, and waste-glass chemical reaction paths are discussed. Glass composition, batching and melter temperature control are used to avoid the information of phases which are disruptive to melting or reduce melter life. The necessity and probable limitations of control for electric melters with complex waste feed compositions are discussed. Preliminary control limits, their bases, and alternative control methods are described for use in the Defense Waste Processing Facility (DWPF) at the US Department of Energy's Savannah River Plant (SRP), and at the West Valley Demonstration Project (WVDP). Slurries of simulated high level radioactive waste and ground glass frit or glass formers have been isothermally reacted and analyzed to identify the sequence of the major chemical reactions in waste vitrification, and their effect on waste-glass production rates. Relatively high melting rates of waste batches containing mixtures of reducing agents (formic acid, sucrose) and nitrates are attributable to exothermic reactions which occur at critical stages in the vitrification process. The effect of foaming on waste glass production rates is analyzed, and limits defined for existing waste-glass melters, based upon measurable thermophysical properties. Through balancing the high nitrate wastes of the WVDP with reducing agents, the high glass melting rates and sustained melting without foaming required for successful WVDP operations have been demonstrated. 65 refs., 4 figs., 15 tabs

  15. Corrosion on air preheaters and economisers; Korrosion hos luftfoervaermare och ekonomisrar

    Nordling, Magnus

    2012-05-15

    Combustion plants in Sweden are exposed to considerable stress regarding low temperature corrosion, and failures due to low temperature corrosion occur regularly. Particularly common is corrosion problems connected to air preheaters and economisers. The number of combustion plants having air preheaters and economisers is however large, and the result of a collection of experiences regarding corrosion on air preheaters and economisers therefore has the potential to give a broad knowledge base. The summary of collection of experiences that has been done here, complemented with a literature survey, is expected to give plant owners and plant constructors a valuable tool to prevent corrosion on the flue gas side of air preheaters and economisers. The choice of plants for the inquiry was made using a list from the Swedish Naturvaardsverket (Environmental Protection Agency) indicating the emissions of NO{sub x}gases from Swedish combustion plants. From that list mainly the plants with the largest emissions were chosen, resulting in a number of 30 plants. Depending on that most of the plants have several boilers, and that the connected tubes often have several economisers and air preheaters, the number of economisers and air preheaters in this experience collection is at least 85. The study was however not limited to economisers and air preheaters, but also experiences connected to corrosion of other units were collected when mentioned, and the most interesting information here is also included in the report. Also a number of the plants were visited to improve the basis of the report, e.g. by photographing the most interesting parts. As the insight of the extension of the problem increased, renewed interview rounds were made, and the last one was made in August 2011.

  16. Sol-Gel Glasses

    Mukherjee, S. P.

    1985-01-01

    Multicomponent homogeneous, ultrapure noncrystalline gels/gel derived glasses are promising batch materials for the containerless glass melting experiments in microgravity. Hence, ultrapure, homogeneous gel precursors could be used to: (1) investigate the effect of the container induced nucleation on the glass forming ability of marginally glass forming compositions; and (2) investigate the influence of gravity on the phase separation and coarsening behavior of gel derived glasses in the liquid-liquid immiscibility zone of the nonsilicate systems having a high density phase. The structure and crystallization behavior of gels in the SiO2-GeO2 as a function of gel chemistry and thermal treatment were investigated. As are the chemical principles involved in the distribution of a second network former in silica gel matrix being investigated. The procedures for synthesizing noncrystalline gels/gel-monoliths in the SiO2-GeO2, GeO2-PbO systems were developed. Preliminary investigations on the levitation and thermal treatment of germania silicate gel-monoliths in the Pressure Facility Acoustic Levitator were done.

  17. Effect of pre-heating on the viscosity and microhardness of a resin composite.

    Lucey, S

    2010-04-01

    The effect of pre-heating resin composite on pre-cured viscosity and post-cured surface hardness was evaluated. Groups of uncured specimens were heated to 60 degrees C and compared with control groups (24 degrees C) with respect to viscosity and surface hardness. Mean (SD) viscosities of the pre-heated specimens (n = 15) were in the range of 285 (13)-377 (11) (Pa) compared with 642 (35)-800 (23) (Pa) at ambient temperature. There was a statistically significant difference between the two groups (P < 0.001). Mean (SD) Vickers microhardness (VHN) of the pre-heated group (n = 15) was 68.6 (2.3) for the top surface and 68.7 (1.8) for the bottom surface measured at 24 h post curing (specimen thickness = 1.5 mm). The corresponding values for the room temperature group were 60.6 (1.4) and 59.0 (3.5). There was a statistically significant difference between corresponding measurements taken at the top and bottom for the pre-heated and room temperature groups (P < 0.001). There was no significant difference between top and bottom measurements within each group. Pre-heating resin composite reduces its pre-cured viscosity and enhances its subsequent surface hardness. These effects may translate as easier placement together with an increased degree of polymerization and depth-of-cure.

  18. Efficiency of the pre-heater against flow rate on primary the beta test loop

    Edy Sumarno; Kiswanta; Bambang Heru; Ainur R; Joko P

    2013-01-01

    Calculation of efficiency of the pre-heater has been carried out against the flow rate on primary the BETA Test Loop. BETA test loop (UUB) is a facilities of experiments to study the thermal hydraulic phenomenon, especially for thermal hydraulic post-LOCA (Lost of Coolant Accident). Sequences removal on the BETA Test Loop contained a pre-heater that serves as a getter heat from the primary side to the secondary side, determination of efficiency is to compare the incoming heat energy with the energy taken out by a secondary fluid. Characterization is intended to determine the performance of a pre-heater, then used as tool for analysis, and as a reference design experiments. Calculation of efficiency methods performed by operating the pre-heater with fluid flow rate variation on the primary side. Calculation of efficiency on the results obtained that the efficiency change with every change of flow rate, the flow rate is 71.26% on 163.50 ml/s and 60.65% on 850.90 ml/s. Efficiency value can be even greater if the pre-heater tank is wrapped with thermal insulation so there is no heat leakage. (author)

  19. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    Wang Hongyue; Zhao Lingling; Zhou Qiangtai; Xu Zhigao; Kim, Hyung Taek

    2008-01-01

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters

  20. Glass sealing

    Brow, R.K.; Kovacic, L.; Chambers, R.S. [Sandia National Labs., Albuquerque, NM (United States)

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  1. Electrochromic Glasses.

    1980-07-31

    this glass and that dipole-dipole correlations contribute to the "ferroelectric-like" character of this amorphous system. The TeO2 -W03 glasses can only...shows the dielectric constant and Fig. I(b) glass from pure TeO2 ot pure WO. In addition, glass the tan 8 of the WO glass as a function of temperature... glasses containing WO, in various glass forming nitworks of LifO-B1O0, Na:O-BzO,, and TeO2 were prepared from reagent grade oxides at 800 C - 9SO C in

  2. BatchJS: Implementing Batches in JavaScript

    D. Kasemier

    2014-01-01

    htmlabstractNone of our popular programming languages know how to handle distribution well. Yet our programs interact more and more with each other and our data resorts in databases and web services. Batches are a new addition to languages that can finally bring native support for distribution to

  3. Effect of Pre-heating on Microtensile Bond Strength of Composite Resin to Dentin.

    Abdolrahim Davari

    2014-10-01

    Full Text Available Direct composite resin restorations are widely used and the impact of different storage temperatures on composites is not well understood. The purpose of this study was to evaluate the microtensile bond strength of composite to dentin after different pre-curing temperatures.Occlusal surfaces of 44 human molars were ground with diamond burs under water coolant and polished with 600 grit silicon carbide papers to obtain flat dentin surfaces. The dentin was etched with 37% phosphoric acid and bonded with Adper Single Bond 2 according to the manufacturer's instructions. The specimens were randomly divided into two groups (n=22 according to the composite resin applied: FiltekP60 and Filtek Z250. Each group included three subgroups of composite resin pre-curing temperatures (4°C, 23°C and 37°C. Composite resins were applied to the dentin surfaces in a plastic mold (8mm in diameter and 4mm in length incrementally and cured. Twenty-two composite-to-dentin hour-glass sticks with one mm(2 cross-sectional area per group were prepared. Microtensile bond strength measurements were made using a universal testing machine at a crosshead speed of one mm/min. For statistical analysis, t-test, one-way and two-way ANOVA were used. The level of significance was set at P<0.05.Filtek P60 pre-heated at 37ºC had significantly higher microtensile bond strength than Filtek Z250 under the same condition. The microtensile bond strengths were not significantly different at 4ºC, 23ºC and 37ºC subgroups of each composite resin group.Filtek P60 and Filtek Z250 did not have significantly different microtensile bond strengths at 4ºC and 23ºC but Filtek P60 had significantly higher microtensile bond strength at 37 ºC. Composite and temperature interactions had significant effects on the bond strength.

  4. Simulated Batch Production of Penicillin

    Whitaker, A.; Walker, J. D.

    1973-01-01

    Describes a program in applied biology in which the simulation of the production of penicillin in a batch fermentor is used as a teaching technique to give students experience before handling a genuine industrial fermentation process. Details are given for the calculation of minimum production cost. (JR)

  5. NDA BATCH 2002-02

    Lawrence Livermore National Laboratory

    2009-12-09

    QC sample results (daily background checks, 20-gram and 100-gram SGS drum checks) were within acceptable criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on 5 drums with IDs LL85101099TRU, LL85801147TRU, LL85801109TRU, LL85300999TRU and LL85500979TRU. All replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. Note that the batch covered 5 weeks of SGS measurements from 23-Jan-2002 through 22-Feb-2002. Data packet for SGS Batch 2002-02 generated using gamma spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with established control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable. An Expert Review was performed on the data packet between 28-Feb-02 and 09-Jul-02 to check for potential U-235, Np-237 and Am-241 interferences and address drum cases where specific scan segments showed Se gamma ray transmissions for the 136-keV gamma to be below 0.1 %. Two drums in the batch showed Pu-238 at a relative mass ratio more than 2% of all the Pu isotopes.

  6. Batching System for Superior Service

    2001-01-01

    Veridian's Portable Batch System (PBS) was the recipient of the 1997 NASA Space Act Award for outstanding software. A batch system is a set of processes for managing queues and jobs. Without a batch system, it is difficult to manage the workload of a computer system. By bundling the enterprise's computing resources, the PBS technology offers users a single coherent interface, resulting in efficient management of the batch services. Users choose which information to package into "containers" for system-wide use. PBS also provides detailed system usage data, a procedure not easily executed without this software. PBS operates on networked, multi-platform UNIX environments. Veridian's new version, PBS Pro,TM has additional features and enhancements, including support for additional operating systems. Veridian distributes the original version of PBS as Open Source software via the PBS website. Customers can register and download the software at no cost. PBS Pro is also available via the web and offers additional features such as increased stability, reliability, and fault tolerance.A company using PBS can expect a significant increase in the effective management of its computing resources. Tangible benefits include increased utilization of costly resources and enhanced understanding of computational requirements and user needs.

  7. Effects of preheated combustion air on laminar coflow diffusion flames under normal and microgravity conditions

    Ghaderi Yeganeh, Mohammad

    Global energy consumption has been increasing around the world, owing to the rapid growth of industrialization and improvements in the standard of living. As a result, more carbon dioxide and nitrogen oxide are being released into the environment. Therefore, techniques for achieving combustion at reduced carbon dioxide and nitric oxide emission levels have drawn increased attention. Combustion with a highly preheated air and low-oxygen concentration has been shown to provide significant energy savings, reduce pollution and equipment size, and uniform thermal characteristics within the combustion chamber. However, the fundamental understanding of this technique is limited. The motivation of the present study is to identify the effects of preheated combustion air on laminar coflow diffusion flames. Combustion characteristics of laminar coflow diffusion flames are evaluated for the effects of preheated combustion air temperature under normal and low-gravity conditions. Experimental measurements are conducted using direct flame photography, particle image velocimetry (PIV) and optical emission spectroscopy diagnostics. Laminar coflow diffusion flames are examined under four experimental conditions: normal-temperature/normal-gravity (case I), preheated-temperature/normal gravity (case II), normal-temperature/low-gravity (case III), and preheated-temperature/low-gravity (case IV). Comparisons between these four cases yield significant insights. In our studies, increasing the combustion air temperature by 400 K (from 300 K to 700 K), causes a 37.1% reduction in the flame length and about a 25% increase in peak flame temperature. The results also show that a 400 K increase in the preheated air temperature increases CH concentration of the flame by about 83.3% (CH is a marker for the rate of chemical reaction), and also increases the C2 concentration by about 60% (C2 is a marker for the soot precursor). It can therefore be concluded that preheating the combustion air

  8. Experimental Investigation of Flow Resistance in a Coal Mine Ventilation Air Methane Preheated Catalytic Oxidation Reactor

    Zheng, Bin; Liu, Yongqi; Liu, Ruixiang; Meng, Jian; Mao, Mingming

    2015-01-01

    This paper reports the results of experimental investigation of flow resistance in a coal mine ventilation air methane preheated catalytic oxidation reactor. The experimental system was installed at the Energy Research Institute of Shandong University of Technology. The system has been used to investigate the effects of flow rate (200 Nm3/h to 1000 Nm3/h) and catalytic oxidation bed average temperature (20°C to 560°C) within the preheated catalytic oxidation reactor. The pressure drop and res...

  9. Solar pre-heating of water for steam generation in the friendship textile mill

    Sid -Ahmed, M.O.; Hussien, T.

    1994-01-01

    The technology of solar water heating is simple and can be used for pre-heating of water entering a boiler. In this paper the economics of solar pre-heating of water was calculated. The calculations were based on the performance and cost of a locally-made flat plate collector, and the performance and fuel consumption of a boiler in a textile mill. The results showed that a collector area of about 800 meter square with initial cost of about LS 5,000,000, could save annually about 130 tons of furnace oil. ( Author )

  10. EFFECT OF PRE-HEAT TREATMENT ON MECHANICAL PROPERTIES OF Ti-6Al-4V WELDS

    Gnofam Jacques TCHEIN

    2016-11-01

    Full Text Available The work presented here is related to the optimization of the Friction Stir Welding (FSW process. The objective is to study the influence of some parameters used in the production of welded joints by FSW. The most important parameters are the welding speed and the rotational speed of the tool. The effect of pre-heat treatment on the plates to be welded is also studied by the design of experimental methods. These pre-heat treatments result not only in a change of mechanical properties of plates to be welded, but also of their microstructure. The experiments were performed following a 16 lines fractional Taguchi table.

  11. Influence of Powder Bed Preheating on Microstructure and Mechanical Properties of H13 Tool Steel SLM Parts

    Mertens, R.; Vrancken, B.; Holmstock, N.; Kinds, Y.; Kruth, J.-P.; Van Humbeeck, J.

    Powder bed preheating is a promising development in selective laser melting (SLM), mainly applied to avoid large thermal stresses in the material. This study analyses the effect of in-process preheating on microstructure, mechanical properties and residual stresses during SLM of H13 tool steel. Sample parts are produced without any preheating and are compared to the corresponding parts made with preheating at 100°, 200°, 300°, and 400°C. Interestingly, internal stresses at the top surface of the parts evolve from compressive (-324MPa) without preheating to tensile stresses (371MPa) with preheating at 400°C. Nevertheless, application of powder bed preheating results in a more homogeneous microstructure with better mechanical properties compared to H13 SLM parts produced without preheating. The fine bainitic microstructure leads to hardness values of 650-700Hv and ultimate tensile strength of 1965MPa, which are comparable to or even better than those of conventionally made and heat treated H13 tool steel.

  12. NGBAuth - Next Generation Batch Authentication for long running batch jobs.

    Juto, Zakarias

    2015-01-01

    This document describes the prototyping of a new solution for the CERN batch authentication of long running jobs. While the job submission requires valid user credentials, these have to be renewed due to long queuing and execution times. Described within is a new system which will guarantee a similar level of security as the old LSFAuth while simplifying the implementation and the overall architecture. The new system is being built on solid, streamlined and tested components (notably OpenSSL) and a priority has been to make it more generic in order to facilitate the evolution of the current system such as for the expected migration from LSF to Condor as backend batch system.

  13. Glass consistency and glass performance

    Plodinec, M.J.; Ramsey, W.G.

    1994-01-01

    Glass produced by the Defense Waste Processing Facility (DWPF) will have to consistently be more durable than a benchmark glass (evaluated using a short-term leach test), with high confidence. The DWPF has developed a Glass Product Control Program to comply with this specification. However, it is not clear what relevance product consistency has on long-term glass performance. In this report, the authors show that DWPF glass, produced in compliance with this specification, can be expected to effectively limit the release of soluble radionuclides to natural environments. However, the release of insoluble radionuclides to the environment will be limited by their solubility, and not glass durability

  14. Area 3, SRC-II coal slurry preheater studies report for the technical data analysis program

    1984-08-01

    This report reviews the raw data gathered from the Preheater B test runs at Ft. Lewis, and also the Preheater B results presented in the Solvent Refined Coal (SRC) Process Final Report, Volumes 1 and 2 of Slurry Preheater Design, SRC-II Process and the Ft. Lewis Slurry Preheater Data Analysis, 1 1/2 Inch Coil by Gulf Science and Technology Corporation of Pittsburgh, Pennsylvania. attempts were made to correlate several variables not previously considered with slurry viscosity and thermal conductivity. Only partial success was realized. However, in the process of attempting to correlate these variables an understanding of why some variables could not be correlated was achieved. An attempt was also made, using multiple linear regression, to correlate coal slurry viscosity and thermal conductivity with several independent variables among which were temperature, coal concentration, total solids, coal type, slurry residence time, shear rate, and unit size. The final correlations included some, but not all, of these independent variables. This report is not a stand alone document and should be considered a supplement to work already done. It should be read in conjunction with the reports referenced above.

  15. Experimental Investigation of the Effects of Concrete Alkalinity on Tensile Properties of Preheated Structural GFRP Rebar

    Hwasung Roh

    2017-01-01

    Full Text Available The combined effects of preexposure to high temperature and alkalinity on the tensile performance of structural GFRP reinforcing bars are experimentally investigated. A total of 105 GFRP bar specimens are preexposed to high temperature between 120°C and 200°C and then immersed into pH of 12.6 alkaline solution for 100, 300, and 660 days. From the test results, the elastic modulus obtained at 300 immersion days is almost the same as those of 660 immersion days. For all alkali immersion days considered in the test, the preheated specimens provide slightly lower elastic modulus than the unpreheated specimens, showing only 8% maximum difference. The tensile strength decreases for all testing cases as the increase of the alkaline immersing time, regardless of the prehearing levels. The tensile strength of the preheated specimens is about 90% of the unpreheated specimen for 300 alkali immersion days. However, after 300 alkali immersion days the tensile strengths are almost identical to each other. Such results indicate that the tensile strength and elastic modulus of the structural GFRP reinforcing bars are closely related to alkali immersion days, not much related to the preheating levels. The specimens show a typical tensile failure around the preheated location.

  16. Preheating to around 100°C under endcap blocks before welding at KHI.

    Loveless, D

    2000-01-01

    The 600mm thick sector blocks of the CMS endcaps are made from three layers of 200mm plates welded together. During the manufacture at KHI, the blocks are preheated to around 100°C to prevent cracks in the welds.

  17. Enhanced preheating after multi-field inflation: on the importance of being special

    Battefeld, Thorsten; Eggemeier, Alexander; Giblin, John T. Jr.

    2012-01-01

    We discuss preheating after multi-field inflation in the presence of several preheat matter fields that become light in the vicinity of (but not at) the inflatons' VEV, at distinct extra-species-points (ESP); this setup is motivated by inflationary models that include particle production during inflation, e.g. trapped inflation, grazing ESP encounters or modulated trapping, among others. While de-phasing of inflatons tends to suppress parametric resonance, we find two new effects leading to efficient preheating: particle production during the first in-fall (efficient if many preheat matter fields are present) and a subsequent (narrow) resonance phase (efficient if an ESP happens to be at one of several distinct distances from the inflatons' VEV). Particles produced during the first in-fall are comprised of many species with low occupation number, while the latter are made up of a few species with high occupation number. We provide analytic descriptions of both phases in the absence of back-reaction, which we test numerically. We further perform lattice simulations to investigate the effects of back-reaction. We find resonances to be robust and the most likely cause of inflaton decay in multi-field trapped inflation if ESP distributions are dense

  18. Effect of air preheat temperature on the MILD combustion of syngas

    Huang, Mingming; Zhang, Zhedian; Shao, Weiwei; Xiong, Yan; Liu, Yan; Lei, Fulin; Xiao, Yunhan

    2014-01-01

    Highlights: • MILD combustion is achieved with reaction zone covering the entire combustion chamber. • Critical equivalence ratio for the occurrence of MILD combustion is identified. • MILD regime can be established for syngas fuel under air preheating conditions. - Abstract: The effect of air preheat temperature on MILD (Moderate or Intense Low-oxygen Dilution) combustion of coal-derived syngas was examined in parallel jet forward flow combustor. The results were presented on flow field using numerical simulations and on global flame signatures, OH ∗ radicals distribution and exhaust emissions using experiments. The discrete and high speed air/fuel injections into the combustor is necessary for the establishment of MILD conditions, because they cause strong gas recirculation and form large mixing region between the air and fuel jets. The critical equivalence ratio above which MILD combustion occurred was identified. The MILD regime was established for syngas fuel under air preheating conditions with lean operational limit and suppressed NO x and CO emissions. In the MILD combustion regime, the air preheating resulted in higher NO x but lower CO emissions, while the increase of equivalence ratio led to the increase of NO x and the decrease of CO emissions

  19. Diagnostics of electron-heated solar flare models. III - Effects of tapered loop geometry and preheating

    Emslie, A. G.; Li, Peng; Mariska, John T.

    1992-01-01

    A series of hydrodynamic numerical simulations of nonthermal electron-heated solar flare atmospheres and their corresponding soft X-ray Ca XIX emission-line profiles, under the conditions of tapered flare loop geometry and/or a preheated atmosphere, is presented. The degree of tapering is parameterized by the magnetic mirror ratio, while the preheated atmosphere is parameterized by the initial upper chromospheric pressure. In a tapered flare loop, it is found that the upward motion of evaporated material is faster compared with the case where the flare loop is uniform. This is due to the diverging nozzle seen by the upflowing material. In the case where the flare atmosphere is preheated and the flare geometry is uniform, the response of the atmosphere to the electron collisional heating is slow. The upward velocity of the hydrodynamic gas is reduced due not only to the large coronal column depth, but also to the increased inertia of the overlying material. It is concluded that the only possible electron-heated scenario in which the predicted Ca XIX line profiles agree with the BCS observations is when the impulsive flare starts in a preheated dense corona.

  20. Effect of pre-heating on the thermal decomposition kinetics of cotton

    The effect of pre-heating at low temperatures (160-280°C) on the thermal decomposition kinetics of scoured cotton fabrics was investigated by thermogravimetric analysis under nonisothermal conditions. Isoconversional methods were used to calculate the activation energies for the pyrolysis after one-...

  1. Enhanced preheating after multi-field inflation: on the importance of being special

    Battefeld, Thorsten; Eggemeier, Alexander [Institute for Astrophysics, University of Goettingen, Friedrich Hund Platz 1, D-37077 Goettingen (Germany); Giblin, John T. Jr., E-mail: tbattefe@astro.physik.uni-goettingen.de, E-mail: a.eggemeier@stud.uni-goettingen.de, E-mail: giblinj@kenyon.edu [Department of Physics, Kenyon College, Gambier, OH 43022 (United States)

    2012-11-01

    We discuss preheating after multi-field inflation in the presence of several preheat matter fields that become light in the vicinity of (but not at) the inflatons' VEV, at distinct extra-species-points (ESP); this setup is motivated by inflationary models that include particle production during inflation, e.g. trapped inflation, grazing ESP encounters or modulated trapping, among others. While de-phasing of inflatons tends to suppress parametric resonance, we find two new effects leading to efficient preheating: particle production during the first in-fall (efficient if many preheat matter fields are present) and a subsequent (narrow) resonance phase (efficient if an ESP happens to be at one of several distinct distances from the inflatons' VEV). Particles produced during the first in-fall are comprised of many species with low occupation number, while the latter are made up of a few species with high occupation number. We provide analytic descriptions of both phases in the absence of back-reaction, which we test numerically. We further perform lattice simulations to investigate the effects of back-reaction. We find resonances to be robust and the most likely cause of inflaton decay in multi-field trapped inflation if ESP distributions are dense.

  2. Symbiotic potential: the integration of preheating and dry cooling in cokemaking

    Barker, J E

    1978-06-01

    In the USSR and Japan, heat recovered from the dry cooling of coke is used to raise steam for power generation or process use. This heat could be used to dry and preheat coal to improve both coke quality and oven productivity.

  3. PROOF on a Batch System

    Behrenhoff, W; Ehrenfeld, W; Samson, J; Stadie, H

    2011-01-01

    The 'parallel ROOT facility' (PROOF) from the ROOT framework provides a mechanism to distribute the load of interactive and non-interactive ROOT sessions on a set of worker nodes optimising the overall execution time. While PROOF is designed to work on a dedicated PROOF cluster, the benefits of PROOF can also be used on top of another batch scheduling system with the help of temporary per user PROOF clusters. We will present a lightweight tool which starts a temporary PROOF cluster on a SGE based batch cluster or, via a plugin mechanism, e.g. on a set of bare desktops via ssh. Further, we will present the result of benchmarks which compare the data throughput for different data storage back ends available at the German National Analysis Facility (NAF) at DESY.

  4. Colloidal glasses

    First page Back Continue Last page Overview Graphics. Colloidal glasses. Glassy state is attained when system fails to reach equilibrium due to crowding of constituent particles. In molecular glasses, glassy state is reached by rapidly lowering the temperature. In colloidal glasses, glassy state is reached by increasing the ...

  5. Silicate glasses

    Lutze, W.

    1988-01-01

    Vitrification of liquid high-level radioactive wastes has received the greatest attention, world-wide, compared to any other HLW solidification process. The waste form is a borosilicate-based glass. The production of phosphate-based glass has been abandoned in the western world. Only in the Soviet Union are phosphate-based glasses still being developed. Vitrification techniques, equipment and processes and their remote operation have been developed and studied for almost thirty years and have reached a high degree of technical maturity. Industrial demonstration of the vitrification process has been in progress since 1978. This chapter is a survey of world-wide research and development efforts in nuclear waste glasses and its production technology. The principal glasses considered are silicate glasses which contain boron, i.e., borosilicate glasses

  6. Evaporation experiments and modelling for glass melts

    Limpt, J.A.C. van; Beerkens, R.G.C.

    2007-01-01

    A laboratory test facility has been developed to measure evaporation rates of different volatile components from commercial and model glass compositions. In the set-up the furnace atmosphere, temperature level, gas velocity and batch composition are controlled. Evaporation rates have been measured

  7. Reproducibility of LiF:Mg, Cup thermoluminescent dosimeter on kilo voltage and megavoltage photon beam using different preheat rate:A glow curve study

    Mohd Fahmi Mohd Yusof; Robert, T.S.B.; Puteri Norkhatijah Abdul Hamid; Nor Shazleen Abdul Shukor; Mohd Sazarman Mohd Salleh

    2013-01-01

    Full-text: Post-irradiation annealing or preheat of the LiF based TLD prior readout is commonly practiced for routine dosimetry to eliminate low temperature glow peaks. The aim of this study is to determine the effect of different preheating rate technique prior readout on the reproducibility and glow curve structure of LiF:Mg, Cu, P or TLD-1OOH exposed to low (109kVp) energy and high energy (6MV) photon beam. TLD chips were read after 24 hours of irradiation with three different preheat techniques; no preheat, low preheat rate (100 degree Celsius/ 10 minutes) and high preheat rate (135 degree Celsius/ 10 seconds) and reproducibility of TL signals were assessed in term of Standard Deviation (SD) and glow curve peaks. The high preheat rate technique was the most reproducible method for low energy photon with 1.05 % of mean reproducibility followed by low preheat rate (1.16 %) and no-preheat (1.33 %) techniques. The high preheat rate techniques was also the most reproducible method for high energy photon with 0.767 % of mean reproducibility as compared to low preheat rate (1.281 %). However the high preheat technique record highest TL signal lost with 10.35 % and 6.04 % for 24 and 72 hours of delayed TLD readout with respectively compared to 9.27 % and 4.51 % for 24 and 72 hours by low preheat rate. The low preheat was found to be optimal to eliminate low peaks (peak 1 and 2) but enable to remove peak 3 as it was shifted up word to combine with the main peak 4 of TL glow peak. It can be concluded that the reproducibility and structure of glow curve was strongly influenced by preheat technique prior readout. (author)

  8. Fining of glass melts: what we know about fining processes today

    Beerkens, R.G.C.

    2009-01-01

    The paper addresses the mechanisms of fining (removal of gases from melt) and the effect of batch composition, oxidation state of the melt and furnace atmosphere on bubble removal processes for commercial glass types, such as float glass and container glass compositions. The mechanisms of the

  9. Recycle Glass in Foam Glass Production

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    The foam glass industry turn recycle glass into heat insulating building materials. The foaming process is relative insensitive to impurities in the recycle glass. It is therefore considered to play an important role in future glass recycling. We show and discuss trends of use of recycled glasses...... in foam glass industry and the supply sources and capacity of recycle glass....

  10. A Model-based B2B (Batch to Batch) Control for An Industrial Batch Polymerization Process

    Ogawa, Morimasa

    This paper describes overview of a model-based B2B (batch to batch) control for an industrial batch polymerization process. In order to control the reaction temperature precisely, several methods based on the rigorous process dynamics model are employed at all design stage of the B2B control, such as modeling and parameter estimation of the reaction kinetics which is one of the important part of the process dynamics model. The designed B2B control consists of the gain scheduled I-PD/II2-PD control (I-PD with double integral control), the feed-forward compensation at the batch start time, and the model adaptation utilizing the results of the last batch operation. Throughout the actual batch operations, the B2B control provides superior control performance compared with that of conventional control methods.

  11. Preheating of manure utilizing heat exchanger and flue gas. Forvarmning af gylle ved varmeveksling med roeggas

    Weber, J.

    1987-07-15

    It has been shown that preheating of manures in biomass conversion plants to a temperature of 50-60 deg. C, before the anaerobic digestion takes place at a temperature of 35-45 deg. C, results in an increase of methane production. But the method normally involves an increase in energy consumption. The aim of the project was to develope methods of utilizing heat from flue gas emitted from the boiler connected to the plant, with the help of a heat exchanger. The heat thus recovered would be used to preheat the manure. The chosen method was to inject the flue gas directly into the manure mass, following this up with heat exchanging and condensing. In order to mix the flue gas thoroughly into the manure an ejector was used, this was driven by the manure flow. Results were satisfactory. (AB).

  12. A pre-heating method based on sinusoidal alternating current for lithium-ion battery

    Fan, Wentao; Sun, Fengchun; Guo, Shanshan

    2018-04-01

    In this paper, a method of low temperature pre-heating of sinusoidal alternating current (SAC) is proposed. Generally, the lower the frequency of the AC current, the higher the heat generation rate. Yet at low frequency, there is a risk of lithium-ion deposition during the half cycle of charging. This study develops a temperature-adaptive, deposition-free AC pre-heating method. a equivalent electric circuit(EEC) model is established to predict the heat generation rate and temperature status, whose parameters are calibrated from the EIS impedance measurements. The effects of current frequency and amplitude on the heating effect are investigated respectively. A multistep temperature-adaptive amplitude strategy is proposed and the cell can be heated from -20°C to 5°C within 509s at 100Hz frequency with this method.

  13. Computational fluid dynamic on the temperature simulation of air preheat effect combustion in propane turbulent flame

    Elwina; Yunardi; Bindar, Yazid

    2018-04-01

    this paper presents results obtained from the application of a computational fluid dynamics (CFD) code Fluent 6.3 to modelling of temperature in propane flames with and without air preheat. The study focuses to investigate the effect of air preheat temperature on the temperature of the flame. A standard k-ε model and Eddy Dissipation model are utilized to represent the flow field and combustion of the flame being investigated, respectively. The results of calculations are compared with experimental data of propane flame taken from literature. The results of the study show that a combination of the standard k-ε turbulence model and eddy dissipation model is capable of producing reasonable predictions of temperature, particularly in axial profile of all three flames. Both experimental works and numerical simulation showed that increasing the temperature of the combustion air significantly increases the flame temperature.

  14. Influence of the Previous Preheating Temperature on the Static Coefficient of Friction with Lubrication

    M. Živković

    2016-12-01

    Full Text Available Experimental investigations static coefficient of friction in lubricated conditions and pre-heating of the sample pin at high temperatures is discussed in this paper. The static coefficient of friction was measured in the sliding steel copper pins per cylinder of polyvinylchloride. Pins are previously heated in a special chamber from room temperature to a temperature of 800 oC with a step of 50 °C. Tribological changes in the surface layer of the pins caused by pre-heating the pins at high temperatures and cooling systems have very significantly influenced the increase in the coefficient of static friction. The results indicate the possibility of improving the friction characteristics of metal materials based on their thermal treatment at elevated temperatures.

  15. Thermodynamic analysis and conceptual design for partial coal gasification air preheating coal-fired combined cycle

    Xu, Yue; Wu, Yining; Deng, Shimin; Wei, Shirang

    2004-02-01

    The partial coal gasification air pre-heating coal-fired combined cycle (PGACC) is a cleaning coal power system, which integrates the coal gasification technology, circulating fluidized bed technology, and combined cycle technology. It has high efficiency and simple construction, and is a new selection of the cleaning coal power systems. A thermodynamic analysis of the PGACC is carried out. The effects of coal gasifying rate, pre-heating air temperature, and coal gas temperature on the performances of the power system are studied. In order to repower the power plant rated 100 MW by using the PGACC, a conceptual design is suggested. The computational results show that the PGACC is feasible for modernizing the old steam power plants and building the new cleaning power plants.

  16. Microshear bond strength of preheated silorane- and methacrylate-based composite resins to dentin.

    Demirbuga, Sezer; Ucar, Faruk Izzet; Cayabatmaz, Muhammed; Zorba, Yahya Orcun; Cantekin, Kenan; Topçuoğlu, Hüseyin Sinan; Kilinc, Halil Ibrahim

    2016-01-01

    The aim of this study was to investigate the effect of preheating on microshear bond strength (MSBS) of silorane and methacrylate-based composite resins to human dentin. The teeth were randomly divided into three main groups: (1) composite resins were heated upto 68 °C; (2) cooled to 4 °C; and (3) control [room temperature (RT)]. Each group was then randomly subdivided into four subgroups according to adhesive system used [Solobond M (Voco), All Bond SE (Bisco), Clearfil SE Bond (CSE) (Kuraray), Silorane adhesive system (SAS) (3M ESPE)]. Resin composite cylinders were formed (0.9 mm diameter × 0.7 mm length) and MSBS of each specimen was tested. The preheated groups exhibited the highest MSBS (p composite resins may be an alternative way to increase the MSBS of composites on dentin. © Wiley Periodicals, Inc.

  17. Acid skim milk gels: The gelation process as affected by preheated pH

    Lakemond, C.M.M.; Vliet, van T.

    2008-01-01

    The effect of preheating milk (10 min 80 [degree sign]C) at pH values from 6.20 to 6.90 on formation of acid skim milk gels was studied by dynamic oscillation measurements. Up to pH 6.65 a higher pH of heating (pHheating) resulted in a higher G'. Since below pH 4.9 the development of

  18. Energetic, Exergetic, and Economic Analysis of MED-TVC Water Desalination Plant with and without Preheating

    Nuri Eshoul

    2018-03-01

    Full Text Available Desalination is the sole proven technique that can provide the necessary fresh water in arid and semi-arid countries in sufficient quantities and meet the modern needs of a growing world population. Multi effect desalination with thermal vapour compression (MED-TVC is one of most common applications of thermal desalination technologies. The present paper presents a comprehensive thermodynamic model of a 24 million litres per day thermal desalination plant, using specialised software packages. The proposed model was validated against a real data set for a large-scale desalination plant, and showed good agreement. The performance of the MED-TVC unit was investigated using different loads, entrained vapour, seawater temperature, salinity and number of effects in two configurations. The first configuration was the MED-TVC unit without preheating system, and the second integrated the MED-TVC unit with a preheating system. The study confirmed that the thermo-compressor and its effects are the main sources of exergy destruction in these desalination plants, at about 40% and 35% respectively. The desalination plant performance with preheating mode performs well due to high feed water temperature leading to the production of more distillate water. The seawater salinity was proportional to the fuel exergy and minimum separation work. High seawater salinity results in high exergy efficiency, which is not the case with membrane technology. The plant performance of the proposed system was enhanced by using a large number of effects due to greater utilisation of energy input and higher generation level. From an economic perspective, both indicators show that using a preheating system is more economically attractive.

  19. Resistive vs. total power depositions by Alfven modes in pre-heated low aspect ratio tokamaks

    Cuperman, S.; Bruma, C.; Komoshvili, K.

    2004-01-01

    The power deposition of fast waves launched by a LFS located antenna in a pre-heated, strongly non-uniform low aspect ratio tokamak (START) is investigated. The rigorous computational results indicate a total power deposition by far larger than that predicted for Alfven continuum eigenmodes in cylindrical plasmas. For toroidal wave numbers |N| > 1, the resistive and total power depositions are almost equal. (author)

  20. Effect of preheating and light-curing unit on physicochemical properties of a bulk fill composite

    Theobaldo JD

    2017-05-01

    Full Text Available Jéssica Dias Theobaldo,1 Flávio Henrique Baggio Aguiar,1 Núbia Inocencya Pavesi Pini,2 Débora Alves Nunes Leite Lima,1 Priscila Christiane Suzy Liporoni,3 Anderson Catelan3 1Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, 2Ingá University Center, Maringá, 3Departament of Dentistry, University of Taubaté, Taubaté, Brazil Objective: The aim of this study is to evaluate the effect of composite preheating and polymerization mode on degree of conversion (DC, microhardness (KHN, plasticization (P, and depth of polymerization (DP of a bulk fill composite.Methods: Forty disc-shaped samples (n = 5 of a bulk fill composite were prepared (5 × 4 mm thick and randomly divided into 4 groups according to light-curing unit (quartz–tungsten–halogen [QTH] or light-emitting diode [LED] and preheating temperature (23 or 54 °C. A control group was prepared with a flowable composite at room temperature. DC was determined using a Fourier transform infrared spectrometer, KHN was measured with a Knoop indenter, P was evaluated by percentage reduction of hardness after 24 h of ethanol storage, and DP was obtained by bottom/top ratio. Data were statistically analyzed by analysis of variance and Tukey’s test (α = 0.05.Results: Regardless of light-curing, the highest preheating temperature increased DC compared to room temperature on bottom surface. LED showed a higher DC compared to QTH. Overall, DC was higher on top surface than bottom. KHN, P, and DP were not affected by curing mode and temperature, and flowable composite showed similar KHN, and lower DC and P, compared to bulk fill.Conclusion: Composite preheating increased the polymerization degree of 4-mm-increment bulk fill, but it led to a higher plasticization compared to the conventional flowable composite evaluated. Keywords: composite resins, physicochemical phenomena, polymerization, hardness, heating

  1. Formation of toroidal pre-heat plasma without residual magnetic field for high-beta pinch experiments

    Ikeda, Nagayasu; Tamaru, Ken; Nagata, Akiyoshi.

    1979-01-01

    Formation of toroidal pre-heat plasma was studied. The pre-heat plasma without residual magnetic field was made by chopping the current for pre-heat, A small toroidal-pinch system was used for the experiment. The magnetic field was measured with a magnetic probe. One turn loop was used for the measurement of the toroidal one-turn electric field. A pair of Rogoski coil was used for the measurement of plasma current. The dependence of residual magnetic field on chopping time was measured. By fast chopping of the primary current in the pre-heating circuit, the poloidal magnetic field was reduced to several percent within 5 microsecond. After chopping, no instability was observed in the principal discharge plasma produced within several microsecond. As the conclusion, it can be said that the control of residual field can be made by current chopping. (Kato, T.)

  2. Phase change material thermal storage for biofuel preheating in micro trigeneration application: A numerical study

    Wu, Dawei; Chen, Junlong; Roskilly, Anthony P.

    2015-01-01

    Highlights: • Engine exhaust heat driven phase change material thermal storage. • Fuel preheating for direct use of straight plant oil on diesel engine. • CFD aided design of the phase change material thermal storage. • Melting and solidification model considering natural convection. - Abstract: A biofuel micro trigeneration prototype has been developed to utilise local energy crop oils as fuel in rural areas and developing countries. Straight plant oils (SPOs) only leave behind very little carbon footprint during its simply production process compared to commercial biodiesels in refineries, but the high viscosity of SPOs causes difficulties at engine cold starts, which further results in poor fuel atomisation, compromised engine performance and fast engine deterioration. In this study, a phase change material (PCM) thermal storage is designed to recover and store engine exhaust heat to preheat SPOs at cold starts. High temperature commercial paraffin is selected as the PCM to meet the optimal preheating temperature range of 70–90 °C, in terms of the SPO property study. A numerical model of the PCM thermal storage is developed and validated by references. The PCM melting and solidification processes with the consideration of natural convection in liquid zone are simulated in ANSYS-FLUENT to verify the feasibility of the PCM thermal storage as a part of the self-contained biofuel micro trigeneration prototype

  3. Experimental investigation of laminar LPG-H{sub 2} jet diffusion flame with preheated reactants

    D.P. Mishra; P. Kumar [Indian Institute of Technology, Kanpur (India). Combustion Laboratory, Department of Aerospace Engineering

    2008-10-15

    This paper presents an experimental investigation of the effect of H{sub 2} addition on flame length, soot free length fraction (SFLF), flame radiant fraction, gas temperature and emission level in LPG-H{sub 2} composite fuel jet diffusion flame for two preheated cases namely, (i) preheated air and (ii) preheated air and fuel. Results show that the H{sub 2} addition leads to a reduction in flame length which may be caused due to an increased gas temperature. Besides this, the flame length is also observed to be reduced with increasing reactants temperature. The soot free length fraction (SFLF) increases as H{sub 2} is added to fuel stream. This might have been caused by decrease in the C/H ratio in the flame and is favorable to attenuate PAH formation rate. Interestingly, the SFLF is observed to be reduced with increasing reactants temperature that may be due to reduction in induction period of soot formation caused by enhanced flame temperature. Moreover, the decreased radiant heat fraction with hydrogen addition is pertinent with the reduction in soot concentration level. The reduction in NOx emission level with H{sub 2} addition to the fuel stream is also observed. On the contrary, NOx emission level is found to be enhanced significantly with reactant temperature that can be attributed to the increase in thermal NOx through Zeldovich mechanism. 31 refs., 4 figs., 2 tabs.

  4. Delayed coking unit preheat train optimization; Otimizacao do preaquecimento das Unidades de Coque

    Marins, Edson R; Geraldelli, Washington O; Barros, Francisco C [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    The oil industry has been investing in research and development of new techniques and process improvements with the objective to increase the residual fraction profitability and to fulfill the market demands. The adequacy of the refining scheme has led to the development of bottom of the barrel processes that has the objective to convert heavy fractions into products of higher aggregate value. In this context, the process of Delayed Coking presents a great importance in the production of distillates in the diesel range as well as the processing of heavy residues, mostly in the markets where the fuel oil consumption is being reduced. With the approach to help PETROBRAS decide which route to follow during new designs of Delayed Coking units, this work presents a comparative study of the preheat train performance among the energy recovery to preheat the feed, in contrast with preheating the feed and generating steam, simultaneously. In this study the Pinch Technology methodology was used as a procedure for heat integration with the objective of getting the maximum energy recovery from the process, finding the best trade-off between operational cost and investment cost. The alternative of steam generation aims to provide an appropriate flexibility in Delayed Coking units design and operation. (author)

  5. Liquid-phase synthesis of vertically aligned carbon nanotubes and related nanomaterials on preheated alloy substrates

    Yamagiwa, Kiyofumi

    2018-02-01

    Carbon nanotubes (CNTs) and related nanocarbons were selectively synthesized on commercially available alloy substrates by a simple liquid-phase technique. Fe- and Ni-rich stainless-steel (JIS SUS316L and Inconel®600, respectively) and Ni-Cu alloy (Monel®400) substrates were used for the synthesis, and each substrate was preheated in air to promote the self-formation of catalyst nanolayers on the surface. The substrates were resistance heated in ethanol without any addition of catalysts to grow CNTs. The yield of the CNTs effectively increased when the preheating process was employed. Highly aligned CNT arrays grew on the SUS316L substrate, while non-aligned CNTs and distinctive twisted fibers were observed on the other substrates. An Fe oxide layer was selectively formed on the preheated SUS316L substrate promoting the growth of the CNT arrays. Characterizations including cyclic voltammetry for the arrays revealed that the CNTs possess a comparatively defect-rich surface, which is a desirable characteristic for its application such as electrode materials for capacitors.

  6. Pre-HEAT: submillimeter site testing and astronomical spectra from Dome A, Antarctica

    Kulesa, C. A.; Walker, C. K.; Schein, M.; Golish, D.; Tothill, N.; Siegel, P.; Weinreb, S.; Jones, G.; Bardin, J.; Jacobs, K.; Martin, C. L.; Storey, J.; Ashley, M.; Lawrence, J.; Luong-Van, D.; Everett, J.; Wang, L.; Feng, L.; Zhu, Z.; Yan, J.; Yang, J.; Zhang, X.-G.; Cui, X.; Yuan, X.; Hu, J.; Xu, Z.; Jiang, Z.; Yang, H.; Li, Y.; Sun, B.; Qin, W.; Shang, Z.

    2008-07-01

    Pre-HEAT is a 20 cm aperture submillimeter-wave telescope with a 660 GHz (450 micron) Schottky diode heterodyne receiver and digital FFT spectrometer for the Plateau Observatory (PLATO) developed by the University of New South Wales. In January 2008 it was deployed to Dome A, the summit of the Antarctic plateau, as part of a scientific traverse led by the Polar Research Institute of China and the Chinese Academy of Sciences. Dome A may be one of the best sites in the world for ground based Terahertz astronomy, based on the exceptionally cold, dry and stable conditions which prevail there. Pre-HEAT is measuring the 450 micron sky opacity at Dome A and mapping the Galactic Plane in the 13CO J=6-5 line, constituting the first submillimeter measurements from Dome A. It is field-testing many of the key technologies for its namesake -- a successor mission called HEAT: the High Elevation Antarctic Terahertz telescope. Exciting prospects for submillimeter astronomy from Dome A and the status of Pre-HEAT will be presented.

  7. Modelling of preheated regenerative chain in Cernavoda NPP using MMS calculation code

    Bigu, M.; Nita, I.; Prisecaru, I.; Dupleac, D.

    2005-01-01

    Full text: In this work it was studied operation of preheated regenerative chain from NPP Cernavoda. To obtain this analysis coupled analyses of condensate system, water supply system, and drain cooler system were effected. The analysis boundaries are: Upstream: - Steam condensers - Turbine Bleed Steam Downstream: - Steam Generators. The analysis was made in two steps: 1) Getting of hydraulic characteristic of pipe network from steam condensers to steam generators at nominal regime; this step was obtained with hydraulic package called PIPENET. 2) Real thermal hydraulic analyses were done based on hydraulic characteristic of pipe network and supplementary data required for heat transfer calculation in equipment of preheated regenerative chain. Thermal analyses were done using MMS package and refered to normal operating regimes, namely, nominal operating regime required for calibration of calculating model, shutdown regime, start-up regime from zero power hot to nominal power and to abnormal operating regimes, namely, turbine trip, reactor trip and loss of two condensate pumps. The results were compared with already existing analysis and showed the largest differences at interface areas (i.e. 5%). This led us to idea of extending analysis to all secondary circuits in order to reduce the number of boundary conditions which can generate uncertainty in analysis. In this analysis we obtained an advanced model of preheated regenerative chain of secondary circuit in Cernavoda NPP which could be extended up to cover the whole secondary circuit by including the analysis of steam generators, turbine, and steam condenser. (authors)

  8. Modelling of preheated regenerative chain in Cernavoda NPP using MMS calculation code

    Bigu, M.; Nita, I.; Prisecaru, I.; Dupleac, D.

    2005-01-01

    In this work it was studied operation of preheated regenerative chain from NPP Cernavoda. To obtain this analysis coupled analyses of condensate system, water supply system, and drain cooler system were effected. The analysis boundaries are: Upstream: - Steam condensers - Turbine Bleed Steam Downstream: - Steam Generators. The analysis was made in two steps: 1) Getting of hydraulic characteristic of pipe network from steam condensers to steam generators at nominal regime; this step was obtained with hydraulic package called PIPENET. 2) Real thermal hydraulic analyses were done based on hydraulic characteristic of pipe network and supplementary data required for heat transfer calculation in equipment of preheated regenerative chain. Thermal analyses were done using MMS package and referred to normal operating regimes, namely, nominal operating regime required for calibration of calculating model, shutdown regime, start-up regime from zero power hot to nominal power and to abnormal operating regimes, namely, turbine trip, reactor trip and loss of two condensate pumps. The results were compared with already existing analysis and showed the largest differences at interface areas (i.e. 5%). This led US to idea of extending analysis to all secondary circuits in order to reduce the number of boundary conditions which can generate uncertainty in analysis. In this analysis we obtained an advanced model of preheated regenerative chain of secondary circuit in Cernavoda NPP which could be extended up to cover the whole secondary circuit by including the analysis of steam generators, turbine, and steam condenser. (authors)

  9. Plasma formation and target preheating by prepulse of PW laser light

    Sentoku, Yasuhiko; Iwata, Natsumi; Koga, James; Dover, Nicholas; Nishiuchi, Mamiko

    2017-10-01

    An intense short pulse laser with intensity over 1021 W/cm2 has become available, i.e. J-KAREN-P at QST. Although the contrast of the short pulse is improved to be of the order of 10-11, there is an unavoidable prepulse, which has multiple spikes (ps) on top of an exponential profile with intensity greater than 1014 W/cm2 about 50 ps in front of the main pulse. The prepulse preheats the target and also produces tenuous plasmas in front of a target before the main pulse arrives. It is critical to understand such preheating of the target, where the nonlocal heat transport is essential at intensity >1014 W/cm2, since the target condition might totally change before the interaction with the main pulse. Using a hydro code, FLASH, and a collisional particle-in-cell code, PICLS, we study the preplasma formation and target preheating over tens of picoseconds timescale, and discuss the prepulse effects on the main pulse interaction. Work supported by the JSPS KAKENHI under Grant No. JP15K21767.

  10. Plan for radionuclide tracer studies of the residence time distribution in the Wilsonville dissolver and preheater

    Jolley, R.L.; Begovich, J.M.; Brashear, H.R.

    1983-12-01

    Stimulus-response measurements using radiotracers to measure residence time distribution (RTD) and hydrodynamic parameters for the preheaters and dissolvers at the Ft. Lewis Solvent Refined Coal (SRC) and the Exxon Donor Solvent (EDS) coal conversion pilot plants are reviewed. A plan is also presented for a series of radioactive tracer studies proposed for the Advanced Coal Liquefaction Facility at Wilsonville, Alabama, to measure the RTD for the preheater and dissolvers in the SRC-I mode. The tracer for the gas phase will be 133 Xe, and 198 Au (on carbonized resin or as an aqueous colloidal suspension) will be used as the slurry tracer. Four experimental phases are recommended for the RTD tracer studies: (1) preheater; (2) dissolver with 100% takeoff; (3) dissolver with 100% takeoff and solids withdrawal; and (4) dissolver with 50% takeoff. Eighteen gas-tracer and 22 liquid-tracer injections are projected to accomplish the four experimental phases. Two to four tracer injections are projected for preliminary tests to ensure the capability of safe injection of the radiotracers and the collection of statistically significant data. A complete projected cost and time schedule is provided, including procurement of necessary components, preparation of the radiotracers, assembly and testing of tracer injection apparatus and detection systems, onsite work and tracer injections, laboratory experimentation, data analysis, and report writing

  11. Tekken tests in a steel 'ASTM A 514 GR B' to determine the preheating temperature

    Quesada, Hector Juan; Zalazar, Monica; Asta, Eduardo Pablo

    2004-01-01

    Cold fissure tests are used to determine the proper preheating temperature in order to prevent fissures during the steel welding process. Tekken tests were carried out on a quenched and tempered high resistance 25.4 mm thick steel (ASTM A514 Gr.B) used in structural applications. The welding was carried out using a FCAW semiautomatic process with gas protection and low hydrogen tubular electrode E110T5-K4. Similar parameters and splicing design were later applied in production. The microstructures of the base material and the welding were determined by optic and electron microscopy. The thermal cycles of the welding were recorded in order to relate the preheating temperature with the cooling time from 800 o C - 500 o C (t 8/5 ) and from 800 o C - 100 o C (tg/1) and the presence or not of fissures. Preheating at 150 o C and t 8/5 greater than 17 s was found to guarantee fissure free welding (CW)

  12. Tekken testing to determine the preheating temperature on ASTM A514 GR B steel

    Asta, Eduardo; Zalazar, Monica; Quesada, Hector

    2003-01-01

    The cold cracking test methods are used to determine the preheating temperature in order to avoid cracking in steel welding.In this work Tekken tests on high strength quenching and tempering (ASTM A514 GrB) structural steel with a thickness of 25 mm have been made.The welds were done using a FCAW process with gas shielding and basic low hydrogen cored wire E 110T5-K4.The welding parameters and joint design applied in this work are similar to the ones used on site production.The base metal, HAZ and weld metal microstructure have been evaluated by optical and SEM microscopy.Thermal cycles records of each welding have been made to relate preheat temperature with the cooling time on the range of 800-500 degC (t8/5) or 800-100degC (t8/1) and the evidence of crack or no crack condition.Finally, a preheat temperature of 150degC and the cooling time larger than 17 s improve a welding integrity without cracks

  13. Cosmos & Glass

    Beim, Anne

    1996-01-01

    The article unfolds the architectural visions of glass by Bruno Taut. It refers to inspirations by Paul Sheerbart and litterature and the Crystal Chain, also it analyses the tectonic univers that can be found in the glass pavillion for the Werkbund exposition in Cologne....

  14. Glass Glimpsed

    Lock, Charles

    2015-01-01

    Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology.......Glass in poetry as it reflects the viewer and as its power of reflection are both reduced and enhanced by technology....

  15. Spin glasses

    Bovier, Anton

    2007-01-01

    Spin glass theory is going through a stunning period of progress while finding exciting new applications in areas beyond theoretical physics, in particular in combinatorics and computer science. This collection of state-of-the-art review papers written by leading experts in the field covers the topic from a wide variety of angles. The topics covered are mean field spin glasses, including a pedagogical account of Talagrand's proof of the Parisi solution, short range spin glasses, emphasizing the open problem of the relevance of the mean-field theory for lattice models, and the dynamics of spin glasses, in particular the problem of ageing in mean field models. The book will serve as a concise introduction to the state of the art of spin glass theory, usefull to both graduate students and young researchers, as well as to anyone curious to know what is going on in this exciting area of mathematical physics.

  16. Research on a Household Dual Heat Source Heat Pump Water Heater with Preheater Based on ASPEN PLUS

    Xiang Gou

    2016-12-01

    Full Text Available This article proposes a dual heat source heat pump bathroom unit with preheater which is feasible for a single family. The system effectively integrates the air source heat pump (ASHP and wastewater source heat pump (WSHP technologies, and incorporates a preheater to recover shower wastewater heat and thus improve the total coefficient of performance (COP of the system, and it has no electric auxiliary heating device, which is favorable to improve the security of the system operation. The process simulation software ASPEN PLUS, widely used in the design and optimization of thermodynamic systems, was used to simulate various cases of system use and to analyze the impact of the preheater on the system. The average COP value of a system with preheater is 6.588 and without preheater it is 4.677. Based on the optimization and analysis, under the standard conditions of air at 25 °C, relative humidity of 70%, wastewater at 35 °C, wastewater flow rate of 0.07 kg/s, tap water at 15 °C, and condenser outlet water temperature at 50 °C, the theoretical COP of the system can reach 9.784 at an evaporating temperature of 14.96 °C, condensing temperature of 48.74 °C, and preheated water temperature of 27.19 °C.

  17. Monte Carlo simulation on kinetics of batch and semi-batch free radical polymerization

    Shao, Jing; Tang, Wei; Xia, Ru; Feng, Xiaoshuang; Chen, Peng; Qian, Jiasheng; Song, Changjiang

    2015-01-01

    experimental and simulation studies, we showed the capability of our Monte Carlo scheme on representing polymerization kinetics in batch and semi-batch processes. Various kinetics information, such as instant monomer conversion, molecular weight

  18. Analysis Of DWPF Sludge Batch 7A (Macrobatch 8) Pour Stream Samples

    Johnson, F.

    2012-01-01

    The Defense Waste Processing Facility (DWPF) began processing Sludge Batch 7a (SB7a), also referred to as Macrobatch 8 (MB8), in June 2011. SB7a is a blend of the heel of Tank 40 from Sludge Batch 6 (SB6) and the SB7a material that was transferred to Tank 40 from Tank 51. SB7a was processed using Frit 418. During processing of each sludge batch, the DWPF is required to take at least one glass sample to meet the objectives of the Glass Product Control Program (GPCP), which is governed by the DWPF Waste Compliance Plan, and to complete the necessary Production Records so that the final glass product may be disposed of at a Federal Repository. Three pour stream glass samples and two Melter Feed Tank (MFT) slurry samples were collected while processing SB7a. These additional samples were taken during SB7a to understand the impact of antifoam and the melter bubblers on glass redox chemistry. The samples were transferred to the Savannah River National Laboratory (SRNL) where they were analyzed. The following conclusions were drawn from the analytical results provided in this report: (1) The sum of oxides for the official SB7a pour stream glass is within the Product Composition Control System (PCCS) limits (95-105 wt%). (2) The average calculated Waste Dilution Factor (WDF) for SB7a is 2.3. In general, the measured radionuclide content of the official SB7a pour stream glass is in good agreement with the calculated values from the Tank 40 dried sludge results from the SB7a Waste Acceptance Program Specification (WAPS) sample. (3) As in previous pour stream samples, ruthenium and rhodium inclusions were detected by Scanning Electron Microscopy-Electron Dispersive Spectroscopy (SEM-EDS) in the official SB7a pour stream sample. (4) The Product Consistency Test (PCT) results indicate that the official SB7a pour stream glass meets the waste acceptance criteria for durability with a normalized boron release of 0.64 g/L, which is an order of magnitude less than the Environmental

  19. Family based dispatching with batch availability

    van der Zee, D.J.

    2013-01-01

    Family based dispatching rules seek to lower set-up frequencies by grouping (batching) similar types of jobs for joint processing. Hence shop flow times may be improved, as less time is spent on set-ups. Motivated by an industrial project we study the control of machines with batch availability,

  20. GLASS BOX

    Curtis, Laura

    2008-01-01

    The goals of this effort were to develop Glass Box capabilities to allow for the capturing of analyst activities and the associated data resources, track and log the results of automated processing...

  1. The effect of preheated tendon as a lean meat replacement on the properties of fine emulsion sausages.

    Sadler, D H; Young, O A

    1993-01-01

    Tendon from beef hind leg muscles was used to replace some of the lean in a conventional emulsion formulation. The tendon was homogenized and either used raw or preheated for 2·5 h at a range of temperatures (50, 60, 70, 80°C) before use. Texture analysis and sensory evaluation were performed on cylinders of cooked sausage. Texture analysis was carried out on formulations which had 20% of meat protein replaced by 20% tendons which were raw or had been preheated to 50, 60, 70, or 80°C. Fracturability decreased by about 40% with raw tendon, but was restored to within 20% of the no-replacement control if the tendon had been preheated. Hardness was approximately doubled by replacement with raw tendon or tendon heated at 50°C. At temperatures higher than that, hardness returned to approximately no-replacement levels. For sensory evaluation (0-25% replacement; preheating at 70°C), sausages were assessed by a 12-member panel for texture, flavour and overall acceptability. All attributes decreased with increasing collagen content, the decrease being less marked with preheated tendon. Thus more connective tissue could be added for the same panel score if the tissue was preheated. Comparison of the texture profile and the panel scores for texture at the same lean replacement level suggested that reduced fracturability was the texture parameter that panellists objected to when heated tendon replaced some of the lean. Other researchers have shown that connective tissue preheated to 100°C before addition in emulsion sausages results in improved yields and better sensory attributes, but the present results show that temperatures as low as 60°C can be effective for beef tendon. Copyright © 1993. Published by Elsevier Ltd.

  2. THE INFLUENCE OF PRE-HEAT TREATMENT ON WHITE CAST IRONS PLASTICITY

    T. M. Myronova

    2013-11-01

    Full Text Available Purpose. The development of heat treatment modes of white cast irons for structure changes in their eutectic constituent, namely in disturbing the monolithic structure of ledeburite colonies cementite structure and eutectic net continuity. Also the mentioned heat treatment modes are targeted to the eutectic net shift for the most suitable position from the point of plastic deforming. Methodology. The hypoeutectic white cast irons with 2.92…3.35 % carbon content and additionally alloyed by 3.18 % vanadium have been used as the research materials. The mentioned alloys have been pre-heat treated and hot twist tested. Findings. The research results showed that the carbide net breaking by plastic deforming leads to cast irons mechanical properties increasing but has difficulties in implementation due to the white cast irons low plasticity. The influence of different pre-heat treatment modes on structure and plasticity of white hypoeutectic cast irons have been investigated. They include the isotherm soaking under the different temperatures as well as multiply soakings and thermo-cycling. The influence of eutectic level, as well as pre heat treatment modes on different composition white cast irons hot plasticity have been investigated. Originality. It was determined that the heat treatment, which leads to double α→γ recrystallization under 860 – 950 °С and reperlitization under 720-680 °С results in significant increase of plasticity, as well as in un-alloyed and alloyed by vanadium white cast irons. It takes place due to carbide matrix phase separation in ledeburite colonies by new phase boundaries forming especially due to carbide transformations under vanadium alloying. Practical value. The implementation of pre-heat treatment with phase recrystallization resulted in hypoeutectic white cast irons plasticity increasing. The obtained level of cast iron plasticity corresponds to the one of carbide class steels, which ensures the successful

  3. Thermal energy analysis of a lime production process: Rotary kiln, preheater and cooler

    Shahin, Hamed; Hassanpour, Saeid; Saboonchi, Ahmad

    2016-01-01

    Highlights: • The integrated model for lime production unit which includes cooler, preheater and rotary kiln is developed. • The effect of residence time in each section on efficiency is investigated. • Influence of material feed rate and excess air on specific fuel consumption is analyzed. • The significant effect of particle size on efficiency and specific fuel consumption is shown. - Abstract: In this paper, thermal energy analysis of three zones of a lime production process, which are preheater, rotary kiln and cooler, is performed. In order to perform a proper quantitative estimation, the system was modeled using energy balance equations including coupled heat transfer and chemical reaction mechanisms. A mathematical model was developed, and consequently, the thermal and chemical behavior of limestone was investigated. The model was verified using empirical data. After model confirmation, the variation of Specific Fuel Consumption (SFC) versus production rate was predicted and the optimum condition was determined. Subsequently, fuel consumption was calculated regarding to altered residence time inside each zone of lime production process, for a constant output. Results indicate that increasing the residence time inside each zone of lime production process, will enhance thermal efficiency and saves fuel consumption. Relative enhancement will be the same for different sizes of limestone. It was found that a 10-min increase in material residence time inside the preheater or rotary kiln can reduce fuel consumption by around two percent. Whereas, a 5-min increase in material residence time inside the cooler would be enough to obtain a similar result. Finally, the ratio of air-to-fuel and production rate are changed in such a way that the same product is achieved. The model predicts that lowering excess air from 15% to 10% leads to a 2.5% reduction of Specific Fuel Consumption (SFC).

  4. Minimizing scatter-losses during pre-heat for magneto-inertial fusion targets

    Geissel, Matthias; Harvey-Thompson, Adam J.; Awe, Thomas J.; Bliss, David E.; Glinsky, Michael E.; Gomez, Matthew R.; Harding, Eric; Hansen, Stephanie B.; Jennings, Christopher; Kimmel, Mark W.; Knapp, Patrick; Lewis, Sean M.; Peterson, Kyle; Schollmeier, Marius; Schwarz, Jens; Shores, Jonathon E.; Slutz, Stephen A.; Sinars, Daniel B.; Smith, Ian C.; Speas, C. Shane; Vesey, Roger A.; Weis, Matthew R.; Porter, John L.

    2018-02-01

    The size, temporal and spatial shape, and energy content of a laser pulse for the pre-heat phase of magneto-inertial fusion affect the ability to penetrate the window of the laser-entrance-hole and to heat the fuel behind it. High laser intensities and dense targets are subject to laser-plasma-instabilities (LPI), which can lead to an effective loss of pre-heat energy or to pronounced heating of areas that should stay unexposed. While this problem has been the subject of many studies over the last decades, the investigated parameters were typically geared towards traditional laser driven Inertial Confinement Fusion (ICF) with densities either at 10% and above or at 1% and below the laser's critical density, electron temperatures of 3-5 keV, and laser powers near (or in excess of) 1 × 1015 W/cm2. In contrast, Magnetized Liner Inertial Fusion (MagLIF) [Slutz et al., Phys. Plasmas 17, 056303 (2010) and Slutz and Vesey, Phys. Rev. Lett. 108, 025003 (2012)] currently operates at 5% of the laser's critical density using much thicker windows (1.5-3.5 μm) than the sub-micron thick windows of traditional ICF hohlraum targets. This article describes the Pecos target area at Sandia National Laboratories using the Z-Beamlet Laser Facility [Rambo et al., Appl. Opt. 44(12), 2421 (2005)] as a platform to study laser induced pre-heat for magneto-inertial fusion targets, and the related progress for Sandia's MagLIF program. Forward and backward scattered light were measured and minimized at larger spatial scales with lower densities, temperatures, and powers compared to LPI studies available in literature.

  5. Preheating ablation effects on the Rayleigh-Taylor instability in the weakly nonlinear regime

    Wang, L. F.; Ye, W. H.; He, X. T.; Sheng, Z. M.; Don, Wai-Sun; Li, Y. J.

    2010-01-01

    The two-dimensional Rayleigh-Taylor instability (RTI) with and without thermal conduction is investigated by numerical simulation in the weakly nonlinear regime. A preheat model κ(T)=κ SH [1+f(T)] is introduced for the thermal conduction [W. H. Ye, W. Y. Zhang, and X. T. He, Phys. Rev. E 65, 057401 (2002)], where κ SH is the Spitzer-Haerm electron thermal conductivity coefficient and f(T) models the preheating tongue effect in the cold plasma ahead of the ablation front. The preheating ablation effects on the RTI are studied by comparing the RTI with and without thermal conduction with identical density profile relevant to inertial confinement fusion experiments. It is found that the ablation effects strongly influence the mode coupling process, especially with short perturbation wavelength. Overall, the ablation effects stabilize the RTI. First, the linear growth rate is reduced, especially for short perturbation wavelengths and a cutoff wavelength is observed in simulations. Second, the second harmonic generation is reduced for short perturbation wavelengths. Third, the third-order negative feedback to the fundamental mode is strengthened, which plays a stabilization role. Finally, on the contrary, the ablation effects increase the generation of the third harmonic when the perturbation wavelengths are long. Our simulation results indicate that, in the weakly nonlinear regime, the ablation effects are weakened as the perturbation wavelength is increased. Numerical results obtained are in general agreement with the recent weakly nonlinear theories as proposed in [J. Sanz, J. Ramirez, R. Ramis et al., Phys. Rev. Lett. 89, 195002 (2002); J. Garnier, P.-A. Raviart, C. Cherfils-Clerouin et al., Phys. Rev. Lett. 90, 185003 (2003)].

  6. Uneven batch data alignment with application to the control of batch end-product quality.

    Wan, Jian; Marjanovic, Ognjen; Lennox, Barry

    2014-03-01

    Batch processes are commonly characterized by uneven trajectories due to the existence of batch-to-batch variations. The batch end-product quality is usually measured at the end of these uneven trajectories. It is necessary to align the time differences for both the measured trajectories and the batch end-product quality in order to implement statistical process monitoring and control schemes. Apart from synchronizing trajectories with variable lengths using an indicator variable or dynamic time warping, this paper proposes a novel approach to align uneven batch data by identifying short-window PCA&PLS models at first and then applying these identified models to extend shorter trajectories and predict future batch end-product quality. Furthermore, uneven batch data can also be aligned to be a specified batch length using moving window estimation. The proposed approach and its application to the control of batch end-product quality are demonstrated with a simulated example of fed-batch fermentation for penicillin production. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  7. Damage to Preheated Tungsten Targets after Multiple Plasma Impacts Simulating ITER ELMs

    Garkusha, I.E.; Bandura, A.N.; Byrka, O.V.; Chebotarev, V.V.; Makhlay, V.A.; Tereshin, V.I. [Kharkov Inst. of Physics and Technology, Inst. of Plasma Physics of National Science Center, Akademicheskaya street, 1, 61108 Kharkov (Ukraine); Landman, I.; Pestchanyi, S. [FZK-Forschungszentrum Karlsruhe, Association Euratom-FZK, Technik und Umwelt, Postfach 3640, D-7602 1 Karlsruhe (Germany)

    2007-07-01

    Full text of publication follows: The energy loads onto ITER divertor surfaces associated with the Type I ELMs are expected to be up to 1 MJ/m{sup 2} during 0.1-0.5 ms, with the number of pulses about 103 per discharge. Tungsten is a candidate material for major part of the surface, but its brittleness can result in substantial macroscopic erosion after the repetitive heat loads. To minimize the brittle destruction, tungsten may be preheated above the ductile-to-brittle transition temperature. In this work the behavior of preheated tungsten targets under repetitive ELM-like plasma pulses is studied in simulation experiments with the quasi-stationary plasma accelerator QSPA Kh-50. The targets have been exposed up to 450 pulses of the duration 0.25 ms and the heat loads either 0.45 MJ/m{sup 2} or 0.75 MJ/m{sup 2}, which is respectively below and above the melting threshold. During the exposures the targets were permanently kept preheated at 650 deg. C by a heater at target backside. In the course of exposures the irradiated surfaces were examined after regular numbers of pulses using the SEM and the optical microscopy. The profilometry, XRD, microhardness and weight loss measurements have been performed, as well as comparisons of surface damages after the heat loads both below and above the melting threshold. It is obtained that macro-cracks do not develop on the preheated surface. After the impacts with surface melting, a fine mesh of intergranular microcracks has appeared. The width of fine intergranular cracks grows with pulse number, achieving 1-1.5 microns after 100 pulses, and after 210 pulses the crack width increases up to 20 microns, which is comparable with grain sizes. Threshold changes in surface morphology resulting in corrugation structures and pits on the surface as well as importance of surface tension in resulted 'micro-brush' structures are discussed. Further evolution of the surface pattern is caused by loss of separated grains on exposed

  8. Experimental and analytical evaluation of preheating temperature during multipass repair welding

    Sedmak Aleksandar S.

    2017-01-01

    Full Text Available Experimental measurement and analytical calculation of preheating, i. e. interpass temperature during multi-pass repair welding has been presented. Analytical calculation is based on heat transfer analysis, whereas measurements have been performed by thermovision camera. Repair welding was performed on crane wheels in the Steelworks Smederevo. Comparison of results indicated that analytical calculation is good enough as the first approximation, but it needs further elaboration, e. g. taking into account the radiation component of heat dissipation and/or temperature dependence of material thermomechanical properties.

  9. Pretreatment and preheating of scrap. Tarkastelu koskien romun esikaesittely- ja esikuumennusmenetelmiae

    Hooli, P.; Hanni, J. (Outokumpu Oy Tornion Tehtaat, Tornio (Finland))

    1990-01-01

    As a background for this study has been those demands for scrap treatments and transportation, which are coming with increasing production of melting shop of Outokumpu Oy's Tornio works and also problems caused by snow among productionrate. Different pretreatment-, transport-, and preheatingmethods and some alternatives has been studied to arrange those as a functioning complete. Also very exact plannings for some pretreatmentmethods has been made. From preheatingmethods some methods, which are concerned to be effective and possible in the future has been studied. In addition those parameters, which are involved to the effectivity of preheating process in melting shop of Outokumpu Oy's Tornio works has been examined.

  10. Pretreatment and preheating of scrap; Tarkastelu koskien romun esikaesittely- ja esikuumennusmenetelmiae

    Hooli, P.; Hanni, J. [Outokumpu Oy Tornion Tehtaat, Tornio (Finland)

    1990-12-31

    As a background for this study has been those demands for scrap treatments and transportation, which are coming with increasing production of melting shop of Outokumpu Oy`s Tornio works and also problems caused by snow among productionrate. Different pretreatment-, transport-, and preheatingmethods and some alternatives has been studied to arrange those as a functioning complete. Also very exact plannings for some pretreatmentmethods has been made. From preheatingmethods some methods, which are concerned to be effective and possible in the future has been studied. In addition those parameters, which are involved to the effectivity of preheating process in melting shop of Outokumpu Oy`s Tornio works has been examined.

  11. SRS SLUDGE BATCH QUALIFICATION AND PROCESSING; HISTORICAL PERSPECTIVE AND LESSONS LEARNED

    Cercy, M.; Peeler, D.; Stone, M.

    2013-09-25

    This report provides a historical overview and lessons learned associated with the SRS sludge batch (SB) qualification and processing programs. The report covers the framework of the requirements for waste form acceptance, the DWPF Glass Product Control Program (GPCP), waste feed acceptance, examples of how the program complies with the specifications, an overview of the Startup Program, and a summary of continuous improvements and lessons learned. The report includes a bibliography of previous reports and briefings on the topic.

  12. Analytical study plan: Shielded Cells batch 1 campaign; Revision 1

    Bibler, N.E.; Ha, B.C.; Hay, M.S.; Ferrara, D.M.; Andrews, M.K.

    1993-01-01

    Radioactive operations in the Defense Waste Processing Facility (DWPF) will require that the Savannah River Technology Center (SRTC) perform analyses and special studies with actual Savannah River Site (SRS) high-level waste sludge. SRS Tank 42 and Tank 51 will comprise the first batch of sludge to be processed in the DWPF. Approximately 25 liters of sludge from each of these tanks will be characterized and processed in the Shielded Cells of SRTC. During the campaign, processes will include sludge characterization, sludge washing, rheology determination, mixing, hydrogen evolution, feed preparation, and vitrification of the waste. To complete the campaign, the glass will be characterized to determine its durability and crystallinity. This document describes the types of samples that will be produced, the sampling schedule and analyses required, and the methods for sample and analytical control

  13. A simple method to prevent hard X-ray-induced preheating effects inside the cone tip in indirect-drive fast ignition implosions

    Liu, Dongxiao; Shan, Lianqiang; Zhou, Weimin; Wu, Yuchi; Zhu, Bin; Zhang, Feng; Bi, Bi; Zhang, Bo; Zhang, Zhimeng; Shui, Min; He, Yingling; Gu, Yuqiu; Zhang, Baohan; Peng, Xiaoshi; Xu, Tao; Wang, Feng; Yang, Zhiwen; Chen, Tao; Chen, Li; Chen, Ming

    2016-01-01

    During fast-ignition implosions, preheating of inside the cone tip caused by hard X-rays can strongly affect the generation and transport of hot electrons in the cone. Although indirect-drive implosions have a higher implosion symmetry, they cause stronger preheating effects than direct-drive implosions. To control the preheating of the cone tip, we propose the use of indirect-drive fast-ignition targets with thicker tips. Experiments carried out at the ShenGuang-III prototype laser facility confirmed that thicker tips are effective for controlling preheating. Moreover, these results were consistent with those of 1D radiation hydrodynamic simulations.

  14. A simple method to prevent hard X-ray-induced preheating effects inside the cone tip in indirect-drive fast ignition implosions

    Liu, Dongxiao; Shan, Lianqiang; Zhou, Weimin; Wu, Yuchi; Zhu, Bin; Zhang, Feng; Bi, Bi; Zhang, Bo; Zhang, Zhimeng; Shui, Min; He, Yingling; Gu, Yuqiu, E-mail: yqgu@caep.cn; Zhang, Baohan [Science and Technology on Plasma Physics Laboratory, China Academy of Engineering Physics, Mianyang 621900 (China); Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Peng, Xiaoshi; Xu, Tao; Wang, Feng; Yang, Zhiwen; Chen, Tao; Chen, Li; Chen, Ming [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); and others

    2016-06-15

    During fast-ignition implosions, preheating of inside the cone tip caused by hard X-rays can strongly affect the generation and transport of hot electrons in the cone. Although indirect-drive implosions have a higher implosion symmetry, they cause stronger preheating effects than direct-drive implosions. To control the preheating of the cone tip, we propose the use of indirect-drive fast-ignition targets with thicker tips. Experiments carried out at the ShenGuang-III prototype laser facility confirmed that thicker tips are effective for controlling preheating. Moreover, these results were consistent with those of 1D radiation hydrodynamic simulations.

  15. The effect of repeated preheating of dimethacrylate and silorane-based composite resins on marginal gap of class V restorations.

    Alizadeh Oskoee, Parnian; Pournaghi Azar, Fatemeh; Jafari Navimipour, Elmira; Ebrahimi Chaharom, Mohammad Esmaeel; Naser Alavi, Fereshteh; Salari, Ashkan

    2017-01-01

    Background. One of the problems with composite resin restorations is gap formation at resin‒tooth interface. The present study evaluated the effect of preheating cycles of silorane- and dimethacrylate-based composite resins on gap formation at the gingival margins of Class V restorations. Methods. In this in vitro study, standard Class V cavities were prepared on the buccal surfaces of 48 bovine incisors. For restorative procedure, the samples were randomly divided into 2 groups based on the type of composite resin (group 1: di-methacrylate composite [Filtek Z250]; group 2: silorane composite [Filtek P90]) and each group was randomly divided into 2 subgroups based on the composite temperature (A: room temperature; B: after 40 preheating cycles up to 55°C). Marginal gaps were measured using a stereomicroscope at ×40 and analyzed with two-way ANOVA. Inter- and intra-group comparisons were analyzed with post-hoc Tukey tests. Significance level was defined at P composite resin type, preheating and interactive effect of these variables on gap formation were significant (Pcomposite resins (Pcomposite resins at room temperature compared to composite resins after 40 preheating cycles (Pcomposite re-sins. Preheating of silorane-based composites can result in the best marginal adaptation.

  16. Viscous Control of the Foam Glass Process

    Petersen, Rasmus Rosenlund; König, Jakob; Smedskjær, Morten Mattrup

    The production of foam glass as heat insulating material is an important industrial process because it enables low-cost recycling of glass waste from a variety of chemical compositions. Optimization of the foaming process of new glass waste compositions is time consuming, since many factors affect...... the foaming process such as temperature, particle size, type and concentration of foaming agent. The foaming temperature is one of the key factors, because even small temperature changes can affect the melt viscosity by several orders of magnitude. Therefore, it is important to establish the viscosity range...... in which the foaming process should take place, particularly when the type of recycled cullet is changed or several types of cullet are mixed in one batch. According to recent glass literature, the foaming process should occur at viscosity 103 to 105 Pa s. However, no systematic studies have hitherto been...

  17. LSF usage for batch at CERN

    Schwickerath, Ulrich

    2007-01-01

    Contributed poster to the CHEP07. Original abstract: LSF 7, the latest version of Platform's batch workload management system, addresses many issues which limited the ability of LSF 6.1 to support large scale batch farms, such as the lxbatch service at CERN. In this paper we will present the status of the evaluation and deployment of LSF 7 at CERN, including issues concerning the integration of LSF 7 with the gLite grid middleware suite and, in particular, the steps taken to endure an efficient reporting of the local batch system status and usage to the Grid Information System

  18. Potential of roof-integrated solar collectors for preheating air at drying facilities in Northern Thailand

    Roman, Franz; Nagle, Marcus; Leis, Hermann; Mueller, Joachim [Institute of Agricultural Engineering 440e, University of Hohenheim, Garbenstrasse 9, 70599 Stuttgart (Germany); Janjai, Serm [Department of Physics, Silpakorn University, Nakhon Pathom (Thailand); Mahayothee, Busarakorn [Department of Food Technology, Silpakorn University, Nakhon Pathom (Thailand); Haewsungcharoen, Methinee [Department of Food Engineering, Chiang Mai University, Chiang Mai (Thailand)

    2009-07-15

    Longan is one of the most widely cropped fruits in Northern Thailand, where a significant amount of the annual harvest is commercially dried and exported as a commodity. Liquefied petroleum gas is generally used as the energy source for heating the drying air, but concern is growing as fuel prices are expected to increase for the foreseeable future. Meanwhile, with the ample solar radiation in Thailand, the roofs of drying facilities could be adapted to serve as solar collectors to preheat the drying air, thus reducing the energy requirement from fossil fuels. In this study, a simulation program for a flat-plate solar air heater was used to estimate the potential to preheat drying air given the conditions of several longan drying facilities. Results showed that solar collectors can replace up to 19.6% of the thermal energy demand during the drying season. Bigger collectors and smaller air channels result in more useful heat, but attention has to be paid to costs and pressure drop, respectively. Annual monetary savings can reach up to THB 56,000 ({approx}US$ 1800 at US$ 1 THB 31). (author)

  19. Experimental study of a single fuel jet in conditions of highly preheated air combustion

    Lille, Simon; Blasiak, W. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Metallurgy

    2000-04-01

    Highly Preheated Air Combustion (HPAC) is a technique to reduce consumption of fuel and decrease NO{sub x} formation in furnaces. The main change that occur in the furnace chamber is that the flow pattern of flue gases changes dramatically resulting in a more uniform heat transfer. The usefulness of regenerative combustion is very clear, but the advantages have so far been accompanied by high levels of pollutants, such as NO{sub x}. The combination of the regeneration technique and internal flue gas recirculation, thus decreasing NO{sub x} and keeping the other advantages, has made HPAC a very attractive combustion technology with application to heat treatment reheating and melting processes. This work gives an introduction to regenerative combustion with diluted air, including theory on flame stabilization. Furthermore, a description of a new test furnace is given with results from a parametric study and from tests using schlieren color visualization, direct photography, and laser Doppler anemometry. In the parametric study NO{sub x}-emission, CO-emission, lift-off, fluctuations, and some flame characteristics are related to nozzle diameter, oxygen concentration, and preheat temperature. For the schlieren technique and direct photography, both still and high-speed cameras were used.

  20. Instrumentation strategies for energy conservation in broiler barns with ventilation air solar pre-heaters

    Cordeau, Sebastien; Barrington, Suzelle [Department of Bioresource Engineering, Macdonald Campus of McGill University, 21 111 Lakeshore, Ste Anne de Bellevue, Quebec H9X 3V9 (Canada)

    2010-08-15

    At the present consumption rate, world fossil-fuel reserves are expected to be depleted by 2050 unless their consumption is optimized and supplemented with renewable energy sources. The objective of this project was to evaluate the performance of a simple data acquisition system installed to conduct an energy balance and identify energy saving strategies in two commercial broilers barns with ventilation air solar pre-heaters. Located near Montreal, Canada, the two identical barns were instrumented for inside and outside air conditions, ventilation rate and energy recovery by the solar air pre-heaters. Whereas the temperature, relative humidity and radiation sensors were reliable, inside air temperature stratification complicated energy balance analyses and broiler heat production rate calculations. Lack of room air mixing resulted in the loss of 25 and 15% of the generated heater load and recovered solar energy. The proper monitoring of all environmental conditions required their measurement every 5 rather than 20 min. Instead of using a data transmission service found to be unreliable in rural areas, all data loggers were downloaded onto a portable computer every 45 days during regular instrument maintenance. Accordingly, room air mixing is recommended to facilitate energy balance studies and improve the efficient use of heating energies. (author)

  1. Gravitational waves from Abelian gauge fields and cosmic strings at preheating

    Dufaux, Jean-Francois; Figueroa, Daniel G.; Garcia-Bellido, Juan

    2010-01-01

    Primordial gravitational waves provide a very important stochastic background that could be detected soon with interferometric gravitational wave antennas or indirectly via the induced patterns in the polarization anisotropies of the cosmic microwave background. The detection of these waves will open a new window into the early Universe, and therefore it is important to characterize in detail all possible sources of primordial gravitational waves. In this paper we develop theoretical and numerical methods to study the production of gravitational waves from out-of-equilibrium gauge fields at preheating. We then consider models of preheating after hybrid inflation, where the symmetry breaking field is charged under a local U(1) symmetry. We analyze in detail the dynamics of the system in both momentum and configuration space. We show that gauge fields leave specific imprints in the resulting gravitational wave spectra, mainly through the appearance of new peaks at characteristic frequencies that are related to the mass scales in the problem. We also show how these new features in the spectra correlate with stringlike spatial configurations in both the Higgs and gauge fields that arise due to the appearance of topological winding numbers of the Higgs around Nielsen-Olesen strings. We study in detail the time evolution of the spectrum of gauge fields and gravitational waves as these strings evolve and decay before entering a turbulent regime where the gravitational wave energy density saturates.

  2. Symbiotic potential: the integration of preheating and dry cooling in cokemaking

    Barker, J E [British Carbonization Research Association, England; Bruce, J M; Kemmetmueller, R

    1978-06-01

    The expression closed energy cycle has become popular in the last decade as descriptive of industrial systems in which exhaust heat is recovered from a primary energy-conversion stage and utilized either recuperatively or regeneratively within the overall complex. An old and well-proven means of utilizing the sensible heat of the incandescent coke discharged from coke ovens is known as dry cooling. This is being practiced widely in the USSR and Japan, but not yet to any significant extent in the western world. The waste heat recovered by this system is normally used to raise steam for power generation and process use. A recent advance in the carbonization of coal for the manufacture of metallurgical coke has been the application of the technique of coal drying and preheating as a means of improving both coke quality and oven productivity, and this is usually energized by burning gas as a fuel. An alternative configuration, having practical advantages in relation to efficiency of utilization of recovered energy and to safety in operation, is represented by a combination of coal drying and preheating with dry cooling of the coke. This paper is concerned with the case for this combination and the means whereby it may be effected in practice. The energy cycle of cokemaking would thus be more nearly closed.

  3. Gasifier selection, design and gasification of oil palm fronds with preheated and unheated gasifying air.

    Guangul, Fiseha M; Sulaiman, Shaharin A; Ramli, Anita

    2012-12-01

    Oil palm frond biomass is abundantly available in Malaysia, but underutilized. In this study, gasifiers were evaluated based on the available literature data and downdraft gasifiers were found to be the best option for the study of oil palm fronds gasification. A downdraft gasifier was constructed with a novel height adjustment mechanism for changing the position of gasifying air and steam inlet. The oil palm fronds gasification results showed that preheating the gasifying air improved the volumetric percentage of H(2) from 8.47% to 10.53%, CO from 22.87% to 24.94%, CH(4) from 2.02% to 2.03%, and higher heating value from 4.66 to 5.31 MJ/Nm(3) of the syngas. In general, the results of the current study demonstrated that oil palm fronds can be used as an alternative energy source in the energy diversification plan of Malaysia through gasification, along with, the resulting syngas quality can be improved by preheating the gasifying air. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Effect of preheat repetition on color stability of methacrylate- and silorane-based composite resins.

    Abed Kahnamouei, Mehdi; Gholizadeh, Sarah; Rikhtegaran, Sahand; Daneshpooy, Mehdi; Kimyai, Soodabeh; Alizadeh Oskoee, Parnian; Rezaei, Yashar

    2017-01-01

    Background. The aim of this study was to investigate the effect of preheating methacrylate- and silorane-based composite resins on their color stability up to 40 times at 55‒60°C. Methods. Seventy-six methacrylate and silorane-based composite resin samples, with a diameter of 10 mm and a height of 2 mm, were divided into 4 groups (n=19). After the samples were prepared, their color parameters were determined using a reflective spectrophotometer. The composite resin samples were separately stored in a solution of tea for 40 consecutive days. Then the samples underwent a color determination procedure again using a spectrophotometer and color changes were recorded. Finally two-way ANOVA was used to study the effect of composite temperature on its staining (Pcomposite resin samples compared to non-heated samples at P=0.005 and P=0.029 for silorane-based and Z250 composite resin samples, respectively. Results. Both composite resin type (P=0.014) and preheating (Pcomposite resin samples, up to 55‒60°C for 40 rounds, resulted in more color changes compared with unheated composite resin samples. After storage in a solution of tea the color change rate in the composite resin samples of silorane-based was higher than the Z250 composite resin samples.

  5. Non-Gaussian and nonscale-invariant perturbations from tachyonic preheating in hybrid inflation

    Barnaby, Neil; Cline, James M.

    2006-05-01

    We show that in hybrid inflation it is possible to generate large second-order perturbations in the cosmic microwave background due to the instability of the tachyonic field during preheating. We carefully calculate this effect from the tachyon contribution to the gauge-invariant curvature perturbation, clarifying some confusion in the literature concerning nonlocal terms in the tachyon curvature perturbation; we show explicitly that such terms are absent. We quantitatively compute the non-Gaussianity generated by the tachyon field during the preheating phase and translate the experimental constraints on the nonlinearity parameter fNL into constraints on the parameters of the model. We also show that nonscale-invariant second-order perturbations from the tachyon field with spectral index n=4 can become larger than the inflaton-generated first-order perturbations, leading to stronger constraints than those coming from non-Gaussianity. The width of the excluded region in terms of the logarithm of the dimensionless coupling g, grows linearly with the log of the ratio of the Planck mass to the tachyon VEV, log⁡(Mp/v); hence very large regions are ruled out if the inflationary scale v is small. We apply these results to string-theoretic brane-antibrane inflation, and find a stringent upper bound on the string coupling, gs<10-4.5.

  6. Modification of preheated tungsten surface after irradiation at the GOL-3 facility

    Shoshin, A.A., E-mail: shoshin@mail.ru [Budker Institute of Nuclear Physics SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Arakcheev, A.S.; Arzhannikov, A.V. [Budker Institute of Nuclear Physics SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Burdakov, A.V. [Budker Institute of Nuclear Physics SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State Technical University, Novosibirsk 630092 (Russian Federation); Huber, A. [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung, 52425 Jülich (Germany); Ivanov, I.A. [Budker Institute of Nuclear Physics SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Kuklin, K.N. [Budker Institute of Nuclear Physics SB RAS, Novosibirsk 630090 (Russian Federation); Polosatkin, S.V.; Postupaev, V.V.; Sinitsky, S.L. [Budker Institute of Nuclear Physics SB RAS, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Vasilyev, A.A. [Novosibirsk State University, Novosibirsk 630090 (Russian Federation)

    2016-12-15

    Highlights: • Preheated tungsten was irradiated at the GOL-3 facility with plasma loads corresponding to the ITER type I ELMs. • The crack pattern and the quantity of bubbles depend on the initial temperatures of the target. • The orientation of major crack networks correlates with the direction of machining of the samples. • Dust impact craters were found. - Abstract: The study is devoted to tungsten surface modification after irradiation at the GOL-3 facility with plasma loads corresponding to the ITER type I ELMs. In order to emulate heating with a steady plasma flux in the ITER divertor, some of the tungsten samples were preheated up to 500 °C. It was found out that the behavior of the surface modification (the crack pattern and the number of bubbles) depends on the initial temperature of the targets. While the orientation of major crack networks correlates with the direction of machining of the samples. Afterwards we have observed the process of craters’ formation caused by dust particle impacts.

  7. Glass compositions

    France, P W

    1985-05-30

    A fluoride glass for use in the production of optical fibres has an enhanced D/H ratio, preferably such that OD:OH is at least 9:1. In the example, such a glass is prepared by treating with D/sub 2/O a melt comprising 51.53 mole per cent ZrF/sub 4/, 20.47 mole per cent BaF/sub 2/, 5.27 mole per cent LaF/sub 3/, 3.24 mole per cent AlF/sub 3/, and 19.49 mole per cent LiF.

  8. Fuzzy batch controller for granular materials

    Zamyatin Nikolaj; Smirnov Gennadij; Fedorchuk Yuri; Rusina Olga

    2018-01-01

    The paper focuses on batch control of granular materials in production of building materials from fluorine anhydrite. Batching equipment is intended for smooth operation and timely feeding of supply hoppers at a required level. Level sensors and a controller of an asynchronous screw drive motor are used to control filling of the hopper with industrial anhydrite binders. The controller generates a required frequency and ensures required productivity of a feed conveyor. Mamdani-type fuzzy infer...

  9. Batch Computed Tomography Analysis of Projectiles

    2016-05-01

    ARL-TR-7681 ● MAY 2016 US Army Research Laboratory Batch Computed Tomography Analysis of Projectiles by Michael C Golt, Chris M...Laboratory Batch Computed Tomography Analysis of Projectiles by Michael C Golt and Matthew S Bratcher Weapons and Materials Research...values to account for projectile variability in the ballistic evaluation of armor. 15. SUBJECT TERMS computed tomography , CT, BS41, projectiles

  10. Effect of the Preheating Temperature on Process Time in Friction Stir Welding of Al 6061-T6

    Jabbari, Masoud

    2013-01-01

    This paper presents the results obtained and the deductions made from an analytical modeling involving friction stir welding of Al 6061-T6. A new database was developed to simulate the contact temperature between the tool and the workpiece. A second-order equation is proposed for simulating...... the temperature in the contact boundary and the thermal history during the plunge phase. The effect of the preheating temperature on the process time was investigated with the proposed model. The results show that an increase of the preheating time leads to a decrease in the process time up to the plunge...

  11. Effect of Ba in the glass characteristics of cesium loaded iron phosphate glasses

    Joseph, Kitheri; Asuvathraman, R.; Vasudeva Rao, P.R.

    2015-01-01

    Radioactive 137 Cs extracted from high level nuclear waste, when immobilized in a suitable matrix can be used as a γsource in medical industry. Iron phosphate glass (IPG) is one of a suitable matrix for the immobilization of 137 Cs prior to the immobilization of 137 Cs in IPG, it is essential to optimize the immobilization conditions using natural (inactive) cesium. Glass characteristics of inactive Cs loaded iron phosphate glasses were already explored in our earlier studies. However, the change in glass characteristics of 137 Cs loaded iron phosphate glass to 137 Ba loaded iron phosphate glass need to be studied before the immobilization of 137 Cs in iron phosphate glass as 137 Cs transforms to 137 Ba due to nuclear transmutation ( 137 Cs(β,γ) 137 Ba). This paper reports the studies on such a behaviour by incorporating inactive Ba in cesium loaded iron phosphate glasses. Cs and Ba loaded iron phosphate glasses were prepared by melt quench technique in air using appropriate amounts of Fe 2 O 3 , NH 4 H 2 PO 4 , Ba(OH) 2.8 H 2 O and Cs 2 CO 3 . The chemicals were added such that the glass formed possesses the batch composition of (a) 21.4 wt. % Fe 2 O 3 -45 wt. % Cs 2 O-5 wt % BaO-P 2 O 5 (henceforth referred as IP50Cs45Ba5); (b) 21.4 wt. % Fe 2 O 3 -25 wt. % Cs 2 O-25 wt % BaO-P 2 O5 (henceforth referred as IP50Cs25Ba25). The thermal expansion measurements were also carried out using a home-built quartz push-rod dilatometer. The data related to change in thermal expansion behaviour, glass forming ability, glass stability and structural changes in phosphate network due to the partial replacement of Cs with Ba will also be discussed. (author)

  12. Glass: Rotary Electric Glass Furnace

    Recca, L.

    1999-01-29

    Compared to conventional gas-fired furnaces, the new rotary electric furnace will increase energy efficiency while significantly reducing air emissions, product turnaround time, and labor costs. As this informative new fact sheet explains, the thousand different types of glass optical blanks produced for the photonics industry are used for lasers, telescopes, cameras, lights, and many other products.

  13. Damage to preheated tungsten targets after multiple plasma impacts simulating ITER ELMs

    Garkusha, I.E. [Institute of Plasma Physics of the NSC KIPT, Akademicheskaya 1, 61108 Kharkov (Ukraine)], E-mail: garkusha@ipp.kharkov.ua; Bandura, A.N.; Byrka, O.V.; Chebotarev, V.V. [Institute of Plasma Physics of the NSC KIPT, Akademicheskaya 1, 61108 Kharkov (Ukraine); Landman, I. [Forschungszentrum Karlsruhe, IHM, 76021 Karlsruhe (Germany); Makhlaj, V.A. [Institute of Plasma Physics of the NSC KIPT, Akademicheskaya 1, 61108 Kharkov (Ukraine); Pestchanyi, S. [Forschungszentrum Karlsruhe, IHM, 76021 Karlsruhe (Germany); Tereshin, V.I. [Institute of Plasma Physics of the NSC KIPT, Akademicheskaya 1, 61108 Kharkov (Ukraine)

    2009-04-30

    The behavior of a preheated at 650 deg. C tungsten targets under repetitive ELM-like plasma pulses is studied in simulation experiments with the quasi-stationary plasma accelerator QSPA Kh-50. The targets have been exposed up to 350 pulses of the duration 0.25 ms and the surface heat loads either 0.45 MJ/m{sup 2} or 0.75 MJ/m{sup 2}, which is below and above the melting threshold, respectively. The development of surface morphology of the exposed targets as well as cracking and swelling at the surface is discussed. First comparisons of obtained experimental results with corresponding numerical simulations of the code PEGASUS-3D are presented.

  14. New Colloidal Lithographic Nanopatterns Fabricated by Combining Pre-Heating and Reactive Ion Etching

    Cong Chunxiao

    2009-01-01

    Full Text Available Abstract We report a low-cost and simple method for fabrication of nonspherical colloidal lithographic nanopatterns with a long-range order by preheating and oxygen reactive ion etching of monolayer and double-layer polystyrene spheres. This strategy allows excellent control of size and morphology of the colloidal particles and expands the applications of the colloidal patterns as templates for preparing ordered functional nanostructure arrays. For the first time, various unique nanostructures with long-range order, including network structures with tunable neck length and width, hexagonal-shaped, and rectangular-shaped arrays as well as size tunable nanohole arrays, were fabricated by this route. Promising potentials of such unique periodic nanostructures in various fields, such as photonic crystals, catalysts, templates for deposition, and masks for etching, are naturally expected.

  15. New pre-heating system for natural gas pressure regulating stations

    Zullo, G.; Vertuani, C.; Borghesani, O.; Vignoli, F.

    1999-01-01

    Costs for running natural gas pressure regulating stations are mainly due to operation and maintenance of a natural gas preheating system, usually equipment with a hot water boiler or an armour-plated electric resistance immersed in a fluid. The article describe a system, considering a natural circulation boiler which uses steam/condensate (at 100 degrees C and 0,5 bar) as a thermal conductor, in thermodynamic balance and in absence of un condensable. This new boiler, already operating with satisfactory results in heating system for industrial buildings, does not require testing, notifications, periodical inspections by the competent authorities, constant monitoring by trained or patented staff. Besides, it allows easier installations procedures and running cost savings. The system, to be considered as static because it has no moving parts, is a good alternative to conventional forced hot water circulation or electric heating system [it

  16. Preheat effect on titanium plate fabricated by sputter-free selective laser melting in vacuum

    Sato, Yuji; Tsukamoto, Masahiro; Shobu, Takahisa; Yamashita, Yorihiro; Yamagata, Shuto; Nishi, Takaya; Higashino, Ritsuko; Ohkubo, Tomomasa; Nakano, Hitoshi; Abe, Nobuyuki

    2018-04-01

    The dynamics of titanium (Ti) melted by laser irradiation was investigated in a synchrotron radiation experiment. As an indicator of wettability, the contact angle between a selective laser melting (SLM) baseplate and the molten Ti was measured by synchrotron X-rays at 30 keV during laser irradiation. As the baseplate temperature increased, the contact angle decreased, down to 28° at a baseplate temperature of 500 °C. Based on this result, the influence of wettability of a Ti plate fabricated by SLM in a vacuum was investigated. It was revealed that the improvement of wettability by preheating suppressed sputtering generation, and a surface having a small surface roughness was fabricated by SLM in a vacuum.

  17. Solid state NMR studies for a new carbonization process with high temperature preheating

    Saito, Koji; Hatakeyama, Moriaki; Komaki, Ikuo; Katoh, Kenji

    2002-01-01

    A new carbonization process with rapid preheating and coke discharging at medium temperature has been developed in Japan. The result of this process shows that even when no or slightly coking coal is by 50 wt% the coking property is improved and a coking coke with cold strength usable at blast furnace can be manufactured with the new carbonization process. The mechanism of the coking property improvement was examined by coal properties using mainly solid state NMR ( 1H CRAMPS and 13C SPE/MAS, CP/MAS) and NMR imaging (single point imaging, in-situ imaging). It has been clarified that the molecular structure of coal is relaxed by the rapid heating treatment and, in addition, there is a close relation between hydrogen bonding and relaxation of the molecular structure of coal.

  18. Study of sensitivity change of OSL signals from quartz and feldspars as a function of preheat temperature

    Jungner, H.; Bøtter-Jensen, L.

    1994-01-01

    and as a result, the equivalent dose (ED) would be underestimated. A study of sensitivity changes in feldspars and quartz was carried out with emphasis on the effect of preheat and annealing on the OSL signal. Measurement results obtained are presented, and possible elimination of errors in dating caused...

  19. Experimental and Modeling Investigation of the Effect of Air Preheat on the Formation of NOx in an RQL Combustor

    Samuelsen, G. S.; Brouwer, J.; Vardakas, M. A.; Holderman, J. D.

    2012-01-01

    The Rich-burn/Quick-mix/Lean-burn (RQL) combustor concept has been proposed to minimize the formation of oxides of nitrogen (NOx) in gas turbine systems. The success of this low-NOx combustor strategy is dependent upon the links between the formation of NOx, inlet air preheat temperature, and the mixing of the jet air and fuel-rich streams. Chemical equilibrium and kinetics modeling calculations and experiments were performed to further understand NOx emissions in an RQL combustor. The results indicate that as the temperature at the inlet to the mixing zone increases (due to preheating and/or operating conditions) the fuel-rich zone equivalence ratio must be increased to achieve minimum NOx formation in the primary zone of the combustor. The chemical kinetics model illustrates that there is sufficient residence time to produce NOx at concentrations that agree well with the NOx measurements. Air preheat was found to have very little effect on mixing, but preheating the air did increase NOx emissions significantly. By understanding the mechanisms governing NOx formation and the temperature dependence of key reactions in the RQL combustor, a strategy can be devised to further reduce NOx emissions using the RQL concept.

  20. Energy efficiency of batch and semi-batch (CCRO) reverse osmosis desalination.

    Warsinger, David M; Tow, Emily W; Nayar, Kishor G; Maswadeh, Laith A; Lienhard V, John H

    2016-12-01

    As reverse osmosis (RO) desalination capacity increases worldwide, the need to reduce its specific energy consumption becomes more urgent. In addition to the incremental changes attainable with improved components such as membranes and pumps, more significant reduction of energy consumption can be achieved through time-varying RO processes including semi-batch processes such as closed-circuit reverse osmosis (CCRO) and fully-batch processes that have not yet been commercialized or modelled in detail. In this study, numerical models of the energy consumption of batch RO (BRO), CCRO, and the standard continuous RO process are detailed. Two new energy-efficient configurations of batch RO are analyzed. Batch systems use significantly less energy than continuous RO over a wide range of recovery ratios and source water salinities. Relative to continuous RO, models predict that CCRO and batch RO demonstrate up to 37% and 64% energy savings, respectively, for brackish water desalination at high water recovery. For batch RO and CCRO, the primary reductions in energy use stem from atmospheric pressure brine discharge and reduced streamwise variation in driving pressure. Fully-batch systems further reduce energy consumption by not mixing streams of different concentrations, which CCRO does. These results demonstrate that time-varying processes can significantly raise RO energy efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Utilization of biogas released from palm oil mill effluent for power generation using self-preheated reactor

    Hosseini, Seyed Ehsan; Wahid, Mazlan Abdul

    2015-01-01

    Highlights: • A lab-scale reactor called self-preheating flameless combustion (SPFC) system is experimented. • Feasibility of power generation by POME biogas is modeled using SPFC system. • 4 MW power is available by POME biogas utilization in a typical palm oil mill with 300,000 tons production. • The rate of power generation increases when 2% hydrogen is added to POME biogas ingredients. - Abstract: In palm oil mills, for one ton crude palm oil (CPO) production, 70 m"3 biogas is released from palm oil mill effluent (POME) which can endanger the environment. Palm oil mills without appropriate strategies for biogas collection can participate in greenhouse gases (GHGs) generation actively. In this paper, a typical palm oil mill with annual capacity of 300,000 ton oil palm production and 3 MW electricity demand is considered as a pilot plant and feasibility of power generation by POME biogas is modeled by Aspen Plus considering flameless mode in combustion system. A new design of lab-scale flameless reactor called self-preheated flameless combustion (SPFC) system is presented and employed in power generation modeling. In SPFC system, the flameless chamber is employed as a heater to preheat an oxidizer over the self-ignition temperature of the fuel. A helical stainless steel pipe (called self-preheating pipe) is installed inside the chamber to conduct the oxidizer from exhaust zone to the combustion zone inside the chamber and preheat oxidizer. In the flameless mode, the diluted oxidizer is injected to the helical pipe from the exhaust zone and the preheated oxidizer at the burner is conducted to the flameless furnace through a distributor. In SPFC system external heater for preheating oxidizer is removed and the rate of power generation increases. The results show that 10.8 MW power could be generated in ultra-lean POME biogas SPFC. However, the rate of pollutant especially CO_2 and NO_x is high in this circumstances. In stoichiometric condition, 4 MW power

  2. Hydrogen preheating through waste heat recovery of an open-cathode PEM fuel cell leading to power output improvement

    Mohamed, W.A.N.W.; Kamikl, M. Haziq M.

    2016-01-01

    Highlights: • A study on the effect of hydrogen preheating using waste heat for low temperature PEM fuel cells. • Theoretical, experimental and analytical framework was established. • The maximum electrical power output increases by 8–10% under specific operating conditions. • Open loop hydrogen supply gives a better performance than closed loop. • The waste heat utilization is less than 10% due to heat capacity limitations. - Abstract: The electrochemical reaction kinetics in a Polymer Electrolyte Membrane (PEM) fuel cell is highly influenced by the reactants supply pressures and electrode temperatures. For an open cathode PEM fuel cell stack, the power output is constrained due to the use of air simultaneously as reactant and coolant. Optimal stack operation temperatures are not achieved especially at low to medium power outputs. Based on the ideal gas law, higher reactant temperatures would lead to higher pressures and subsequently improve the reaction kinetics. The hydrogen supply temperature and its pressure can be increased by preheating; thus, slightly offsetting the limitation of low operating stack temperatures. The exit air stream offers an internal source of waste heat for the hydrogen preheating purpose. In this study, a PEM open-cathode fuel cell was used to experimentally evaluate the performance of hydrogen preheating based on two waste heat recovery approaches: (1) open-loop and (2) closed loop hydrogen flow. The stack waste heat was channelled into a heat exchanger to preheat the hydrogen line before it is being supplied (open loop) or resupplied (closed loop) into the stack. At a constant 0.3 bar hydrogen supply pressure, the preheating increases the hydrogen temperature in the range of 2–13 °C which was dependant on the stack power output and cathode air flow rates. The achievable maximum stack power was increased by 8% for the closed loop and 10% for the open loop. Due to the small hydrogen flow rates, the waste heat utilization

  3. Nitrate glass

    Kirilenko, I.A.; Vinogradov, E.E.

    1977-01-01

    Experimental evidence on behaviour of nitrate glasses is reviewed in terms of relationships between the presence of water in vitrescent nitrate systems and the properties of the systems. The glasses considered belong to systems of Mg(NO 3 ) 2 - Nd(NO 3 ) 3 ; Hg(NO 3 ) 2 -Nd(NO 3 ) 3 ; NaNO 3 -Mg(NO 3 ) 2 -Nd(NO 3 ) 3 ; M-Zn(NO 3 ) 3 , where M is a mixture of 20% mass NaNO 3 and 80% mass Mg(NO 3 ) 2 , and Zn is a rare earth ion. Nitrate glass is shown to be a product of dehydration. Vitrification may be regarded as a resusl of formation of molecular complexes in the chain due to hydrogen bonds of two types, i.e. water-water, or water-nicrate group. Chain formation, along with low melting points of the nitrates, hinder crystallization of nitrate melts. Provided there is enough water, this results in vitrification

  4. PLUTONIUM SOLUBILITY IN HIGH-LEVEL WASTE ALKALI BOROSILICATE GLASS

    Marra, J.; Crawford, C.; Fox, K.; Bibler, N.

    2011-01-04

    The solubility of plutonium in a Sludge Batch 6 (SB6) reference glass and the effect of incorporation of Pu in the glass on specific glass properties were evaluated. A Pu loading of 1 wt % in glass was studied. Prior to actual plutonium glass testing, surrogate testing (using Hf as a surrogate for Pu) was conducted to evaluate the homogeneity of significant quantities of Hf (Pu) in the glass, determine the most appropriate methods to evaluate homogeneity for Pu glass testing, and to evaluate the impact of Hf loading in the glass on select glass properties. Surrogate testing was conducted using Hf to represent between 0 and 1 wt % Pu in glass on an equivalent molar basis. A Pu loading of 1 wt % in glass translated to {approx}18 kg Pu per Defense Waste Processing Facility (DWPF) canister, or about 10X the current allowed limit per the Waste Acceptance Product Specifications (2500 g/m{sup 3} of glass or about 1700 g/canister) and about 30X the current allowable concentration based on the fissile material concentration limit referenced in the Yucca Mountain Project License Application (897 g/m{sup 3}3 of glass or about 600 g Pu/canister). Based on historical process throughput data, this level was considered to represent a reasonable upper bound for Pu loading based on the ability to provide Pu containing feed to the DWPF. The task elements included evaluating the distribution of Pu in the glass (e.g. homogeneity), evaluating crystallization within the glass, evaluating select glass properties (with surrogates), and evaluating durability using the Product Consistency Test -- Method A (PCT-A). The behavior of Pu in the melter was evaluated using paper studies and corresponding analyses of DWPF melter pour samples.The results of the testing indicated that at 1 wt % Pu in the glass, the Pu was homogeneously distributed and did not result in any formation of plutonium-containing crystalline phases as long as the glass was prepared under 'well-mixed' conditions

  5. Plutonium Solubility In High-Level Waste Alkali Borosilicate Glass

    Marra, J.; Crawford, C.; Fox, K.; Bibler, N.

    2011-01-01

    The solubility of plutonium in a Sludge Batch 6 (SB6) reference glass and the effect of incorporation of Pu in the glass on specific glass properties were evaluated. A Pu loading of 1 wt % in glass was studied. Prior to actual plutonium glass testing, surrogate testing (using Hf as a surrogate for Pu) was conducted to evaluate the homogeneity of significant quantities of Hf (Pu) in the glass, determine the most appropriate methods to evaluate homogeneity for Pu glass testing, and to evaluate the impact of Hf loading in the glass on select glass properties. Surrogate testing was conducted using Hf to represent between 0 and 1 wt % Pu in glass on an equivalent molar basis. A Pu loading of 1 wt % in glass translated to ∼18 kg Pu per Defense Waste Processing Facility (DWPF) canister, or about 10X the current allowed limit per the Waste Acceptance Product Specifications (2500 g/m 3 of glass or about 1700 g/canister) and about 30X the current allowable concentration based on the fissile material concentration limit referenced in the Yucca Mountain Project License Application (897 g/m 3 3 of glass or about 600 g Pu/canister). Based on historical process throughput data, this level was considered to represent a reasonable upper bound for Pu loading based on the ability to provide Pu containing feed to the DWPF. The task elements included evaluating the distribution of Pu in the glass (e.g. homogeneity), evaluating crystallization within the glass, evaluating select glass properties (with surrogates), and evaluating durability using the Product Consistency Test -- Method A (PCT-A). The behavior of Pu in the melter was evaluated using paper studies and corresponding analyses of DWPF melter pour samples.The results of the testing indicated that at 1 wt % Pu in the glass, the Pu was homogeneously distributed and did not result in any formation of plutonium-containing crystalline phases as long as the glass was prepared under 'well-mixed' conditions. The incorporation of 1 wt

  6. Fuzzy batch controller for granular materials

    Zamyatin Nikolaj

    2018-01-01

    Full Text Available The paper focuses on batch control of granular materials in production of building materials from fluorine anhydrite. Batching equipment is intended for smooth operation and timely feeding of supply hoppers at a required level. Level sensors and a controller of an asynchronous screw drive motor are used to control filling of the hopper with industrial anhydrite binders. The controller generates a required frequency and ensures required productivity of a feed conveyor. Mamdani-type fuzzy inference is proposed for controlling the speed of the screw that feeds mixture components. As related to production of building materials based on fluoride anhydrite, this method is used for the first time. A fuzzy controller is proven to be effective in controlling the filling level of the supply hopper. In addition, the authors determined optimal parameters of the batching process to ensure smooth operation and production of fluorine anhydrite materials of specified properties that can compete with gypsum-based products.

  7. History based batch method preserving tally means

    Shim, Hyung Jin; Choi, Sung Hoon

    2012-01-01

    In the Monte Carlo (MC) eigenvalue calculations, the sample variance of a tally mean calculated from its cycle-wise estimates is biased because of the inter-cycle correlations of the fission source distribution (FSD). Recently, we proposed a new real variance estimation method named the history-based batch method in which a MC run is treated as multiple runs with small number of histories per cycle to generate independent tally estimates. In this paper, the history-based batch method based on the weight correction is presented to preserve the tally mean from the original MC run. The effectiveness of the new method is examined for the weakly coupled fissile array problem as a function of the dominance ratio and the batch size, in comparison with other schemes available

  8. Following an Optimal Batch Bioreactor Operations Model

    Ibarra-Junquera, V.; Jørgensen, Sten Bay; Virgen-Ortíz, J.J.

    2012-01-01

    The problem of following an optimal batch operation model for a bioreactor in the presence of uncertainties is studied. The optimal batch bioreactor operation model (OBBOM) refers to the bioreactor trajectory for nominal cultivation to be optimal. A multiple-variable dynamic optimization of fed...... as the master system which includes the optimal cultivation trajectory for the feed flow rate and the substrate concentration. The “real” bioreactor, the one with unknown dynamics and perturbations, is considered as the slave system. Finally, the controller is designed such that the real bioreactor...

  9. Supervision of Fed-Batch Fermentations

    Gregersen, Lars; Jørgensen, Sten Bay

    1999-01-01

    Process faults may be detected on-line using existing measurements based upon modelling that is entirely data driven. A multivariate statistical model is developed and used for fault diagnosis of an industrial fed-batch fermentation process. Data from several (25) batches are used to develop...... a model for cultivation behaviour. This model is validated against 13 data sets and demonstrated to explain a significant amount of variation in the data. The multivariate model may directly be used for process monitoring. With this method faults are detected in real time and the responsible measurements...

  10. Exploring the Transition From Batch to Online

    Jørgensen, Anker Helms

    2010-01-01

    of the truly interactive use of computers known today. The transition invoked changes in a number of areas: technological, such as hybrid forms between batch and online; organisational such as decentralization; and personal as users and developers alike had to adopt new technology, shape new organizational...... structures, and acquire new skills. This work-in-progress paper extends an earlier study of the transition from batch to online, based on oral history interviews with (ex)-employees in two large Danish Service Bureaus. The paper takes the next step by ana-lyzing a particular genre: the commercial computer...

  11. DWPF waste glass Product Composition Control System

    Brown, K.G.; Postles, R.L.

    1992-01-01

    The Defense Waste Processing Facility (DWPF) will be used to blend aqueous radwaste (PHA) with solid radwaste (Sludge) in a waste receipt vessel (the SRAT). The resulting SRAT material is transferred to the SME an there blended with ground glass (Frit) to produce a batch of melter feed slurry. The SME material is passed to a hold tank (the MFT) which is used to continuously feed the DWPF melter. The melter. The melter produces a molten glass wasteform which is poured into stainless steel canisters for cooling and, ultimately, shipment to and storage in a geologic repository. The Product Composition Control System (PCCS) is the system intended to ensure that the melt will be processible and that the glass wasteform will be acceptable. This document provides a description of this system

  12. Coated Glass Slides TACAS Are Applicable to Heat-Assisted Immunostaining and In Situ Hybridization at the Electron Microscopy Level

    Matsui, Takahiro; Onouchi, Takanori; Shiogama, Kazuya; Mizutani, Yasuyoshi; Inada, Ken-ichi; Yu, Fuxun; Hayasaka, Daisuke; Morita, Koichi; Ogawa, Hirohisa; Mahara, Fumihiko; Tsutsumi, Yutaka

    2015-01-01

    We performed pre-embedding electron microscopic study for visualizing the antigen and genome of severe fever with thrombocytopenia syndrome (SFTS) virus in the cytoplasm of macrophages of the human splenic red pulp, both requesting preheating treatment of sections. To pursue this, coated glass slides with unique characteristics are needed. Namely, during staining they must prevent detaching off sections, but after staining the sections must be transferred to epoxy resin. Aminopropyltriexoxysilane-coated glass slides, widely used for immunostaining, were resistant to transfer to epoxy resin. In contrast, coated glass slides designated as Thinlayer Advanced Cytology Assay System (TACAS) were suitable for this purpose. The technique is also applicable to the coated glass slide-requiring cytology practice, in which immunocytochemical evaluation is needed after cell transfer to another glass slide

  13. Cordierite Glass-Ceramics for Dielectric Materials

    Siti Mazatul Azwa Saiyed Mohd Nurddin; Selamat, Malek; Ismail, Abdullah

    2007-01-01

    The objective of this project is to examine the potential of using Malaysian silica sand deposit as SiO2 raw material in producing cordierite glass-ceramics (2MgO-2Al2O3-5SiO2) for dielectric materials. Upgraded silica sands from Terengganu and ex-mining land in Perak were used in the test-works. The glass batch of the present work has a composition of 45.00% SiO2, 24.00% Al2O3, 15.00% MgO and 8.50% TiO2 as nucleation agent. From the differential thermal analysis results, the crystallization temperature was found to start around 900 deg. C. The glass samples were heat-treated at 900 deg. C and 1000 deg. C. The X-ray diffraction analysis (XRD) results showed glass-ceramics from Terengganu samples containing mainly cordierite and minor β-quartz crystals. However, glass-ceramics from ex-mining land samples contained mainly α-quartz and minor cordierite crystals. Glass-ceramics with different crystal phases exhibit different mechanical, dielectric and thermal properties. Based on the test works, both silica sand deposits, can be potentially used to produce dielectric material component

  14. Production of nattokinase by batch and fed-batch culture of Bacillus subtilis.

    Cho, Young-Han; Song, Jae Yong; Kim, Kyung Mi; Kim, Mi Kyoung; Lee, In Young; Kim, Sang Bum; Kim, Hyeon Shup; Han, Nam Soo; Lee, Bong Hee; Kim, Beom Soo

    2010-09-30

    Nattokinase was produced by batch and fed-batch culture of Bacillus subtilis in flask and fermentor. Effect of supplementing complex media (peptone, yeast extract, or tryptone) was investigated on the production of nattokinase. In flask culture, the highest cell growth and nattokinase activity were obtained with 50 g/L of peptone supplementation. In this condition, nattokinase activity was 630 unit/ml at 12 h. In batch culture of B. subtilis in fermentor, the highest nattokinase activity of 3400 unit/ml was obtained at 10h with 50 g/L of peptone supplementation. From the batch kinetics data, it was shown that nattokinase production was growth-associated and culture should be harvested before stationary phase for maximum nattokinase production. In fed-batch culture of B. subtilis using pH-stat feeding strategy, cell growth (optical density monitored at 600 nm) increased to ca. 100 at 22 h, which was 2.5 times higher than that in batch culture. The highest nattokinase activity was 7100 unit/ml at 19 h, which was also 2.1 times higher than that in batch culture. Copyright 2010 Elsevier B.V. All rights reserved.

  15. Systematic Methodology for Reproducible Optimizing Batch Operation

    Bonné, Dennis; Jørgensen, Sten Bay

    2006-01-01

    This contribution presents a systematic methodology for rapid acquirement of discrete-time state space model representations of batch processes based on their historical operation data. These state space models are parsimoniously parameterized as a set of local, interdependent models. The present...

  16. Batch extractive distillation for high purity methanol

    Zhang Weijiang; Ma Sisi

    2006-01-01

    In this paper, the application in chemical industry and microelectronic industry, market status and the present situation of production of high purity methanol at home and abroad were introduced firstly. Purification of industrial methanol for high purity methanol is feasible in china. Batch extractive distillation is the best separation technique for purification of industrial methanol. Dimethyl sulfoxide was better as an extractant. (authors)

  17. Monitoring of batch processes using spectroscopy

    Gurden, S. P.; Westerhuis, J. A.; Smilde, A. K.

    2002-01-01

    There is an increasing need for new techniques for the understanding, monitoring and the control of batch processes. Spectroscopy is now becoming established as a means of obtaining real-time, high-quality chemical information at frequent time intervals and across a wide range of industrial

  18. Crystallization and properties of a spodumene-willemite glass ceramic

    Hu, A.M.; Li, M.; Dali, D.L. Mao; Liang, K.M.

    2005-01-01

    Spodumene-willemite glass ceramics were produced by replacement of Al 2 O 3 in lithium aluminium silicate by ZnO. With replacement of Al 2 O 3 by ZnO, the batch melting temperature, glass transition temperature (T g ) and crystallization temperature (T p ) all decreased. The main crystalline phases precipitated were eucriptite, β-spodumene and willemite (Zn 2 SiO 4 ). All compositions of glass ceramics showed bulk crystallization. As ZnO content increased, the grain sizes and thermal expansion coefficients increased, while the flexural strength and fracture toughness of the glass-ceramics increased first, and then decreased. The mechanical properties were correlated with crystallization and morphology of glass ceramics

  19. Investigations on oxy-fuel combustion in glass melting furnaces; Untersuchungen zur Oxy-Fuel-Feuerung in Glasschmelzwannen

    Leicher, Joerg; Giese, Anne [Gaswaerme-Institut e.V., Essen (Germany)

    2011-12-15

    Glass melting requires process temperatures of more than 1600 C which are usually achieved using intensive air preheating and near-stoichiometric combustion. This often leads to high nitrous oxide emissions (NO{sub x}). Oxy-fuel technology offers an interesting alternative since high combustion temperatures can be achieved using pure oxygen as oxidizer while obtaining low NO{sub x} emissions. In the course of the AiF research project ''O2-Glaswanne'' (IGF-Nr.: 15987 N), Gaswaerme- Institut e.V. Essen investigates this combustion process by experimental and numerical means in order to determine potential optimization approaches for glass melting furnaces.

  20. Monte Carlo simulation on kinetics of batch and semi-batch free radical polymerization

    Shao, Jing

    2015-10-27

    Based on Monte Carlo simulation technology, we proposed a hybrid routine which combines reaction mechanism together with coarse-grained molecular simulation to study the kinetics of free radical polymerization. By comparing with previous experimental and simulation studies, we showed the capability of our Monte Carlo scheme on representing polymerization kinetics in batch and semi-batch processes. Various kinetics information, such as instant monomer conversion, molecular weight, and polydispersity etc. are readily calculated from Monte Carlo simulation. The kinetic constants such as polymerization rate k p is determined in the simulation without of “steady-state” hypothesis. We explored the mechanism for the variation of polymerization kinetics those observed in previous studies, as well as polymerization-induced phase separation. Our Monte Carlo simulation scheme is versatile on studying polymerization kinetics in batch and semi-batch processes.

  1. Multi-objective optimization of glycopeptide antibiotic production in batch and fed batch processes

    Maiti, Soumen K.; Eliasson Lantz, Anna; Bhushan, Mani

    2011-01-01

    batch operations using process model for Amycolatopsis balhimycina, a glycopeptide antibiotic producer. This resulted in a set of several pareto optimal solutions with the two objectives ranging from (0.75gl−1, 3.97g$-1) to (0.44gl−1, 5.19g$-1) for batch and from (1.5gl−1, 5.46g$-1) to (1.1gl−1, 6.34g...

  2. Medication waste reduction in pediatric pharmacy batch processes.

    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.

  3. Multiple Magma Batches Recorded in Tephra Deposits from the Toba Complex, Sumatra.

    Pearce, N. J. G.; Westgate, J.; Gatti, E.

    2015-12-01

    The Toba Caldera Complex is the largest Quaternary caldera on Earth, and has generated three voluminous and compositionally similar rhyolitic tuffs, viz. the Oldest (OTT, 800 ka), Middle (MTT, ~500 ka) and Youngest Toba Tuffs (YTT, 75 ka). These tephra deposits are widespread across Indonesia, Malaysia, South China Sea, Sea of Bengal, India and Indian Ocean and provide useful stratigraphic markers in oceanic, lacustrine and terrestrial environments. Single shard trace element analysis of these deposits reveals the changing availability of different batches of magma through time, with Sr, Ba and Y contents defining 5 discrete magma populations in YTT, 4 populations in MTT and only a single, low Ba population in OTT. Within an individual eruption these populations are clearly distinct, but between eruptions (e.g. MTT and YTT) some of these populations overlap while others do not, indicating both the longevity (and/or continuous supply of fresh material) and evolution of these magma batches in the Toba Complex. Major element compositions of the different groups show equilibration at different pressures (based on Q'-Ab'-Or'), with the equilibration of low Ba populations at ~160 MPa, increasing to depths of ~210 MPa for the highest Ba population. The proportions of different populations of glass in distal YTT shows that relatively little of the high Ba population makes it into the distal record across India, and that this population appears to be over-represented in the proximal free glass and pumice from the caldera walls. This data may shed light on magma availability and tephra dispersal during the YTT eruption. Similarly, the glass composition of individual pumices from proximal deposits record regional, compositional and temporal differences in the erupted products. These show, for example, the apparent mingling of some of the magma batches and also that the high Ba population appears early (i.e. stratigraphically lower) in the northern caldera wall.

  4. Surface Characteristics of Machined NiTi Shape Memory Alloy: The Effects of Cryogenic Cooling and Preheating Conditions

    Kaynak, Y.; Huang, B.; Karaca, H. E.; Jawahir, I. S.

    2017-07-01

    This experimental study focuses on the phase state and phase transformation response of the surface and subsurface of machined NiTi alloys. X-ray diffraction (XRD) analysis and differential scanning calorimeter techniques were utilized to measure the phase state and the transformation response of machined specimens, respectively. Specimens were machined under dry machining at ambient temperature, preheated conditions, and cryogenic cooling conditions at various cutting speeds. The findings from this research demonstrate that cryogenic machining substantially alters austenite finish temperature of martensitic NiTi alloy. Austenite finish ( A f) temperature shows more than 25 percent increase resulting from cryogenic machining compared with austenite finish temperature of as-received NiTi. Dry and preheated conditions do not substantially alter austenite finish temperature. XRD analysis shows that distinctive transformation from martensite to austenite occurs during machining process in all three conditions. Complete transformation from martensite to austenite is observed in dry cutting at all selected cutting speeds.

  5. Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-Ray Preheat

    Colvin, Jeffrey D.; Kalantar, Daniel H.

    2006-01-01

    To drive shocks into solids with a laser we either illuminate the material directly, or to get higher pressures, illuminate a plastic ablator that overlays the material of interest. In both cases the illumination intensity is low, <<1013 W/cm2, compared to that for traditional laser fusion targets. In this regime, the laser beam creates and interacts with a collisional, rather than a collisionless, plasma. We present scaling relationships for shock pressure with intensity derived from simulations for this low-intensity collisional plasma regime. In addition, sometimes the plastic-ablator targets have a thin flash-coating of Al on the plastic surface as a shine-through barrier; this Al layer can be a source of hot x-ray preheat. We discuss how the preheat affects the shock pressure, with application to simulating VISAR measurements from experiments conducted on various lasers on shock compression of Fe

  6. Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-ray Preheat

    Colvin, J D; Kalantar, D H

    2005-01-01

    To drive shocks into solids with a laser we either illuminate the material directly, or to get higher pressures, illuminate a plastic ablator that overlays the material of interest. In both cases the illumination intensity is low, 13 W/cm 2 , compared to that for traditional laser fusion targets. In this regime, the laser beam creates and interacts with a collisional, rather than a collisionless, plasma. We present scaling relationships for shock pressure with intensity derived from simulations for this low-intensity collisional plasma regime. In addition, sometimes the plastic-ablator targets have a thin flashcoating of Al on the plastic surface as a shine-through barrier; this Al layer can be a source of hot x-ray preheat. We discuss how the preheat affects the shock pressure, with application to simulating VISAR measurements from experiments conducted on various lasers on shock compression of Fe

  7. X-ray emission, ablation pressure, and preheating for foils irradiated at 0. 26. mu. m wavelength

    Pepin, H.; Fabbro, R.; Faral, B.; Amiranoff, F.; Virmont, J.; Cottet, F.; Romain, J.P.

    1985-11-01

    The x-ray emission, ablation pressure, and preheating for foils irradiated with a 0.26 ..mu..m laser at intensities approx.10/sup 15/ W cm/sup -2/ are studied. The foils are Al with various thicknesses, coated or uncoated with CH or Au. The x-ray emission and conversion efficiency are obtained with a multichannel x-ray diode spectrometer, the ablation pressures are deduced from shock transit times, and the rear temperatures are inferred from x-ray pyrometry. For thin foils (<<12 ..mu..m), the rear temperatures can be predicted reasonably well with the use of the front x-ray spectra. For thick foils shock preheating is dominant.

  8. X-ray emission, ablation pressure, and preheating for foils irradiated at 0.26 μm wavelength

    Pepin, H.; Fabbro, R.; Faral, B.; Amiranoff, F.; Virmont, J.; Cottet, F.; Romain, J.P.

    1985-01-01

    The x-ray emission, ablation pressure, and preheating for foils irradiated with a 0.26 μm laser at intensities approx.10 15 W cm -2 are studied. The foils are Al with various thicknesses, coated or uncoated with CH or Au. The x-ray emission and conversion efficiency are obtained with a multichannel x-ray diode spectrometer, the ablation pressures are deduced from shock transit times, and the rear temperatures are inferred from x-ray pyrometry. For thin foils (<<12 μm), the rear temperatures can be predicted reasonably well with the use of the front x-ray spectra. For thick foils shock preheating is dominant

  9. Design of a DCS Based Model for Continuous Leakage Monitoring System of Rotary Air Preheater of a Thermal Power Plant

    Madan BHOWMICK

    2011-01-01

    Full Text Available The leakage in rotary air preheater makes a considerable contribution to the reduced overall efficiency of fossil-fuel-fired thermal power plants and increase the effect on environment. Since it is normal phenomenon, continuous monitoring of leakage is generally omitted in most power plants. But for accurate analysis of the operation of the thermal power plant, this leakage monitoring plays a vital role. In the present paper, design of a DCS based model for continuous leakages monitoring of rotary air preheater has been described. In the proposed model, the existing DCS based instrumentation system has been modified and online leakage monitoring system has been developed. This model has been installed in a captive power plant with high capacity boilers and very much satisfactory operation of this system has been observed. The observed online data along with their analysis results are presented in this paper.

  10. An economic and performance design study of solar preheaters for domestic hot water heaters in North Carolina

    Jones, C. B.; Smetana, F. O.

    1977-01-01

    The performance and estimated material costs for several solar preheaters for domestic hot water heaters using isolation levels present in North Carolina are presented. The effects of monthly variations in isolation and the direction of incident radiation are included. Demand is assumed at 13 gallons (49.2 liters) per day per person. The study shows that a closed circulation system with 82 gallons (310 liters) of preheated storage and 53.4 cu ft (4.94 cu m) of collector surface with single cover can be expected to cost about $800 and to repay it capital cost and interest (at 8%) in 5.2 years, assuming present electric rates increase at 5% per year.

  11. Modeling of crude oil fouling in preheat exchangers of refinery distillation units

    Jafari Nasr, Mohammad Reza; Majidi Givi, Mehdi [National Petrochemical Research and Technology Company (NPC-RT), P.O. Box 14385, Tehran (Iran)

    2006-10-15

    The aim of this paper is to propose a new model for crude oil fouling in preheat exchangers of crude distillation units. The experimental results of Australian light crude oil with the tube side surface temperature between 200 and 260{sup o}C and fluid velocity ranged 0.25-0.4m/s were used [Z. Saleh, R. Sheikholeslami, A.P. Watkinson, Heat exchanger fouling by a light australian crude oil, in: Heat Exchanger Fouling and Cleaning Fundamentals and Applications, Santa Fe, 2003]. The amount of activation energy depends on the surface temperature has been calculated. A new model including a term for fouling formation and a term for fouling removal due to chemical and tube wall shear stress was proposed, respectively. The main superiority of the model are independent to Pr number, thermal fouling removal and determination of {beta} based on experimental tests. Finally using the proposed model the fouling rate of Australian light crude oil has been calculated and the threshold curves to identify fouling and no fouling formation zones have been drawn. (author)

  12. Effect of substrate preheating temperature and coating thickness on residual stress in plasma sprayed hydroxyapatite coating

    Tang, Dapei

    2015-01-01

    A thermal-mechanical coupling model was developed based on thermal-elastic- plastic theory according the special process of plasma spraying Hydroxyapatite (HA) coating upon Ti-6Al-4V substrate. On the one hand, the classical Fourier transient heat conduction equation was modified by introducing the effect item of deformation on temperature, on the other hand, the Johnson-Cook model, suitable for high temperature and high strain rate conditions, was used as constitutive equation after considering temperature softening effect, strain hardening effect and strain rate reinforcement effect. Based on the above coupling model, the residual stress field within the HA coating was simulated by using finite element method (FEM). Meanwhile, the substrate preheating temperature and coating thickness on the influence of residual stress components were calculated, respectively. The failure modes of coating were also preliminary analyzed. In addition, in order to verify the reliability of calculation, the material removal measurement technique was applied to determine the residual stress of HA coating near the interface. Some important conclusions are obtained. (paper)

  13. Synthesis and physical properties of zinc-oxide textured films by using a filtered preheated hydrothermal

    Qiu, Jijun; Shin, Dongmyeong; He, Weizhen; Kim, Hyungkook; Hwang, Yoonhwae; Li, Xiaomin; Gao, Xiangdong

    2014-01-01

    Axially (c-axis)-oriented ZnO thick films with a ∼8.1 μm thickness were fabricated on ZnO seed layer coated substrates by using a filtered preheated hydrothermal solution. The thick films composed of single-crystal ZnO microrods with various diameters were formed by coalescing each nanorod together along their side surfaces. From the X-ray diffraction result a biaxial stress exists was found to exist in the as-grown thick films, and the stress gradually increased with increasing annealing temperatures from 200 to 550 .deg. C due to a degradation in the crystalline quality. The biaxial stress is responsible for the red-shift of the optical band gap of the ZnO thick films. Photoluminescence and Hall results revealed that the optical and the electrical properties of the thick films were degenerated after high-temperature annealing (> 200 .deg. C), which was due to the introduction of point defects, such as oxygen interstitials and zinc vacancies.

  14. Ways to achieve optimum utilization of waste gas heat in cement kiln plants with cyclone preheaters

    Steinbiss, E

    1986-02-01

    Kiln exit gases and the exhaust gases from clinker coolers often cannot be fully utilized in drying plants. In such cases a part of the heat content of the gases should be utilized for water heating. In addition, it is possible to utilize the waste gas heat in conventional steam boilers, with which, depending on design, it is possible to generate electricity at a rate of between 10-30 kWh/t (net output). A new and promising method of utilization of waste gas heat is provided by precalcining systems with bypass, in which up to 100% of the kiln exit gases can be economically bypassed and be utilized in a steam boiler, without requiring any cooling. A development project, already started, gives information on the operational behaviour of such a plant and on the maximum energy recoverable. Alternatively, the bypass gases may, after partial cooling with air or preheater exit gas, be dedusted and then utilized in a grinding/drying plant. Furthermore, they can be used in the cement grinding process for the drying of wet granulated blastfurnace slag or other materials. For this it is not necessary to dedust the bypass gases.

  15. Synthesis and physical properties of zinc-oxide textured films by using a filtered preheated hydrothermal

    Qiu, Jijun [Pusan National University, Busan (Korea, Republic of); Shin, Dongmyeong; He, Weizhen; Kim, Hyungkook; Hwang, Yoonhwae [Pusan National University, Miryang (Korea, Republic of); Li, Xiaomin; Gao, Xiangdong [Chinese Academy of Sciences, Shanghai (China)

    2014-11-15

    Axially (c-axis)-oriented ZnO thick films with a ∼8.1 μm thickness were fabricated on ZnO seed layer coated substrates by using a filtered preheated hydrothermal solution. The thick films composed of single-crystal ZnO microrods with various diameters were formed by coalescing each nanorod together along their side surfaces. From the X-ray diffraction result a biaxial stress exists was found to exist in the as-grown thick films, and the stress gradually increased with increasing annealing temperatures from 200 to 550 .deg. C due to a degradation in the crystalline quality. The biaxial stress is responsible for the red-shift of the optical band gap of the ZnO thick films. Photoluminescence and Hall results revealed that the optical and the electrical properties of the thick films were degenerated after high-temperature annealing (> 200 .deg. C), which was due to the introduction of point defects, such as oxygen interstitials and zinc vacancies.

  16. Combustion analysis of preheated crude sunflower oil in an IDI diesel engine

    Canakci, Mustafa; Ozsezen, Ahmet Necati; Turkcan, Ali [Department of Mechanical Education, Kocaeli University, 41380 Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Izmit (Turkey)

    2009-05-15

    In this study, preheated crude sunflower oil (PCSO) was tested for combustion and emission properties against petroleum based diesel fuel (PBDF) in a naturally aspirated, indirect injection (IDI) engine. The cylinder gas pressure and heat release curves for PCSO at 75 C were similar to those of PBDF. The ignition delays for the PCSO were longer and the start of injection timing was earlier than for PBDF. The difference in the average brake torque was a decrease of 1.36% for PCSO though this was statistically insignificant. The brake specific fuel consumption increased by almost 5% more or less in proportion to the difference in calorific value, so that the 1.06% increase in thermal efficiency was again statistically insignificant. The emission test results showed that the decreases in CO{sub 2} emissions and smoke opacity 2.05% and 4.66%, respectively; however, this was not statistically significant, though in line with the apparent increase in thermal efficiency. There was a significant 34% improvement in the emissions of unburnt hydrocarbons. Carbon monoxide increased by 1.77% again the result was not statistically significant given the small number of repeat tests. The use of PCSO does not have any negative effects on the engine performance and emissions in short duration engine testing. (author)

  17. Useful work and the thermal efficiency in the ideal Lenolr cycle with regenerative preheating

    Georgiou, Demos P.

    2000-11-01

    In the existing thermal engine concepts negative work transfer (usually needed to drive a compression process) is supplied by the work produced by the engine itself. The remaining difference (i.e., the net work transfer) becomes the useful work, since it is available for external consumption. The thermal efficiency is the parameter that compares this against the heat input into the system. It forms the main optimization parameter in any engine design. The objective of the present study is to show that for the case of the Lenoir cycle with regenerative preheating the entire positive work is available for external consumption, since the negative (i.e., the compression) work is supplied by the atmospheric air. Not only this, but, during the compression process and due to the pressure difference across the two sides of the moving piston, an additional (useful) work transfer may be generated. Thus, the proposed power plant may be considered as a combination of a thermal engine and a wind turbine. In the ideal cycle limit (at least), the total amount of useful work exceeds the heat entering the system. This leads to the definition of a new parameter for the efficiency (called the technical efficiency), which compares the combined positive work transfer (i.e., the useful one) against the heat entering the system and which may exceed the 100% level.

  18. Application of ground-to-air heat exchanger for preheating of supply air

    Sorokins, Juris; Borodinecs, Anatolijs; Zemitis, Jurgis

    2017-10-01

    This study focuses on assessing the contribution of the passive ground-coupled air heat exchanger system to decreasing the energy consumption of air conditioning and ventilation systems for office buildings in the Latvian climate conditions. The theoretical part of the thesis deals with methods of office building ventilation, supply air preheating and heat recovery as well as particularities of using ground-coupled air heat exchangers, their design parameters and their joint impact on the thermal performance. The engineering project part includes a ventilation system for an office building with an integrated ground-coupled air heat exchanger. By simulating energy consumption of the ventilation system for a duration of one year, the thesis analyzes the contribution of the heat exchanger to the overall energy consumption, which totals 9.53 MWh and 4.02 MWh a year, according to the desired parameters of the indoor climate. The possible alternative heat recovery solutions are investigated to reach by European Regional Development Fund project Nr.1.1.1.1/16/A/048 “NEARLY ZERO ENERGY SOLUTIONS FOR UNCLASSIFIED BUILDINGS”.

  19. FAILURE ANALYSIS IN TUBING OF AIR PREHEATER OF BOILER FROM A SUGARCANE MILL

    Joner Oliveira Alves

    2014-10-01

    Full Text Available The increased demand for energy from sugarcane bagasse has made the sugar and alcohol mills search alternatives to reduce maintenance of the boilers, releasing more time to the production. The stainless steel use has become one of the main tools for such reduction. However, specification errors can lead to premature failures. This work reports the factors that led tubes of AISI 409 stainless steel fail after half season when applied in a air preheater of boiler from a sugarcane mill. In such application, the AISI 304 lasts about 15 seasons and the carbon steel about 3. A tube sent by the sugar mill was characterized by wet chemical analysis, optical microscopy and EDS. Results indicated chloride formation on the internal walls of the tube, which combined with the environment, accelerated the corrosion process. The carbon steel showed high lifetime due to a 70% higher thickness. Due to the work condictions is recommended the use of stainless steels with higher corrosion resistance, such as the traditional AISI 304 or the ferritic AISI 444, the last presents better thermal exchange.

  20. Establishment of welding process without PWHT and preheating in SGV480 plate for nuclear reactor containment vessel

    Watanabe, Nozomu; Higashikubo, Tomohiro; Nagamura, Takafumi; Yoshimoto Kentaro

    2000-01-01

    Ordinances of Japan's Ministry of International Trade and Industry provide that welded joints more than 38 mm thick used in nuclear reactor containment vessels undergo Post Weld Heat Treatment (PWHT). PWHT is difficult to apply in the field, however. We made SGV480 plate tougher and more weldable by using a Thermo-Mechanical Control Process (TMCP) in rolling. Such plate can be used without PWHT or preheating up to 55 mm thick at lowest service temperature -19degC. (author)

  1. Recent advances in Pt coating of microspheres by a batch magnetron sputtering process

    Hsieh, E.J.; Meyer, S.F.

    1980-01-01

    Some proposed inertial confinement fusion targets require high-Z, high density metal coatings on glass microspheres. Platinum, which satisfies the high-Z and density requirements, can be coated onto microspheres with a batch magnetron sputtering process incorporating oxygen as a dopant gas to prevent the microspheres from sticking. This paper outlines recent progress in three areas: First, the coating process has been improved; second, the oxygen content and resistivity of the oxygen doped platinum films are analyzed; and third, the roles oxygen may play in reducing microsphere sticking during sputtering are discussed in regard to cold welding, Van der Waals bonding, electrostatic sticking, and sintering

  2. Optimal operation of batch membrane processes

    Paulen, Radoslav

    2016-01-01

    This study concentrates on a general optimization of a particular class of membrane separation processes: those involving batch diafiltration. Existing practices are explained and operational improvements based on optimal control theory are suggested. The first part of the book introduces the theory of membrane processes, optimal control and dynamic optimization. Separation problems are defined and mathematical models of batch membrane processes derived. The control theory focuses on problems of dynamic optimization from a chemical-engineering point of view. Analytical and numerical methods that can be exploited to treat problems of optimal control for membrane processes are described. The second part of the text builds on this theoretical basis to establish solutions for membrane models of increasing complexity. Each chapter starts with a derivation of optimal operation and continues with case studies exemplifying various aspects of the control problems under consideration. The authors work their way from th...

  3. Recycling of Glass

    Christensen, Thomas Højlund; Damgaard, Anders

    2011-01-01

    Glass is used for many purposes, but in the waste system glass is predominantly found in terms of beverage and food containers with a relatively short lifetime before ending up in the waste. Furthermore there is a large amount of flat glass used in building materials which also ends up in the waste...... system; this glass though has a long lifetime before ending up in the waste. Altogether these product types add up to 82% of the production of the European glass industry (IPCC, 2001). Recycling of glass in terms of cleaning and refilling of bottles as well as the use of broken glass in the production...... of new glass containers is well established in the glass industry. This chapter describes briefly howglass is produced and howwaste glass is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of glass recycling....

  4. Effect of pre-heating on the chemical oxidation efficiency: implications for the PAH availability measurement in contaminated soils.

    Biache, Coralie; Lorgeoux, Catherine; Andriatsihoarana, Sitraka; Colombano, Stéfan; Faure, Pierre

    2015-04-09

    Three chemical oxidation treatments (KMnO4, H2O2 and Fenton-like) were applied on three PAH-contaminated soils presenting different properties to determine the potential use of these treatments to evaluate the available PAH fraction. In order to increase the available fraction, a pre-heating (100 °C under N2 for one week) was also applied on the samples prior oxidant addition. PAH and extractable organic matter contents were determined before and after treatment applications. KMnO4 was efficient to degrade PAHs in all the soil samples and the pre-heating slightly improved its efficiency. H2O2 and Fenton-like treatments presented low efficiency to degrade PAH in the soil presenting poor PAH availability, however, the PAH degradation rates were improved with the pre-heating. Consequently H2O2-based treatments (including Fenton-like) are highly sensitive to contaminant availability and seem to be valid methods to estimate the available PAH fraction in contaminated soils. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Effect of bond coat and preheat on the microstructure, hardness, and porosity of flame sprayed tungsten carbide coatings

    Winarto, Winarto; Sofyan, Nofrijon; Rooscote, Didi

    2017-06-01

    Thermally sprayed coatings are used to improve the surface properties of tool steel materials. Bond coatings are commonly used as intermediate layers deposited on steel substrates (i.e. H13 tool steel) before the top coat is applied in order to enhance a number of critical performance criteria including adhesion of a barrier coating, limiting atomic migration of the base metal, and corrosion resistance. This paper presents the experimental results regarding the effect of nickel bond coat and preheats temperatures (i.e. 200°C, 300°C and 400°C) on microstructure, hardness, and porosity of tungsten carbide coatings sprayed by flame thermal coating. Micro-hardness, porosity and microstructure of tungsten carbide coatings are evaluated by using micro-hardness testing, optical microscopy, scanning electron microscopy, and X-ray diffraction. The results show that nickel bond coatings reduce the susceptibility of micro crack formation at the bonding area interfaces. The percentage of porosity level on the tungsten carbide coatings with nickel bond coat decreases from 5.36 % to 2.78% with the increase of preheat temperature of the steel substrate of H13 from 200°C to 400°C. The optimum hardness of tungsten carbide coatings is 1717 HVN in average resulted from the preheat temperature of 300°C.

  6. Influence of preheating on API 5L-X80 pipeline joint welding with self shielded flux-cored wire

    Cooper, R.; Silva, J. H. F.; Trevisan, R. E.

    2004-01-01

    The present work refers to the characterization of API 5L-X80 pipeline joints welded with self-shielded flux cored wire. This process was evaluated under preheating conditions, with an uniform and steady heat input. All joints were welded in flat position (1G), with the pipe turning and the torch still. Tube dimensions were 762 mm in external diameter and 16 mm in thickness. Welds were applied on single V-groove, with six weld beads, along with three levels of preheating temperatures (room temperature, 100 degree centigree, 160 degree centigree). These temperatures were maintained as inter pass temperature. The filler metal E71T8-K6 with mechanical properties different from parent metal was used in under matched conditions. The weld characterization is presented according to the mechanical test results of tensile strength, hardness and impact test. The mechanical tests were conducted according to API 1104, AWS and ASTM standards. API 1104 and API 51 were used as screening criteria. According to the results obtained, it was possible to remark that it is appropriate to weld API 5L-X80 steel ducts with Self-shielded Flux Cored wires, in conformance to the API standards and no preheat temperature is necessary. (Author) 22 refs

  7. Batch calculations in CalcHEP

    Pukhov, A.

    2003-01-01

    CalcHEP is a clone of the CompHEP project which is developed by the author outside of the CompHEP group. CompHEP/CalcHEP are packages for automatic calculations of elementary particle decay and collision properties in the lowest order of perturbation theory. The main idea prescribed into the packages is to make available passing on from the Lagrangian to the final distributions effectively with a high level of automation. According to this, the packages were created as a menu driven user friendly programs for calculations in the interactive mode. From the other side, long-time calculations should be done in the non-interactive regime. Thus, from the beginning CompHEP has a problem of batch calculations. In CompHEP 33.23 the batch session was realized by mean of interactive menu which allows to the user to formulate the task for batch. After that the not-interactive session was launched. This way is too restricted, not flexible, and leads to doubling in programming. In this article I discuss another approach how one can force an interactive program to work in non-interactive mode. This approach was realized in CalcHEP 2.1 disposed on http://theory.sinp.msu.ru/~pukhov/calchep.html

  8. Pollution prevention applications in batch manufacturing operations

    Sykes, Derek W.; O'Shaughnessy, James

    2004-02-01

    Older, "low-tech" batch manufacturing operations are often fertile grounds for gains resulting from pollution prevention techniques. This paper presents a pollution prevention technique utilized for wastewater discharge permit compliance purposes at a batch manufacturer of detergents, deodorants, and floor-care products. This manufacturer generated industrial wastewater as a result of equipment rinses required after each product batch changeover. After investing a significant amount of capital on end of pip-line wastewater treatment technology designed to address existing discharge limits, this manufacturer chose to investigate alternate, low-cost approaches to address anticipated new permit limits. Mass balances using spreadsheets and readily available formulation and production data were conducted on over 300 products to determine how each individual product contributed to the total wastewater pollutant load. These mass balances indicated that 22 products accounted for over 55% of the wastewater pollutant. Laboratory tests were conducted to determine whether these same products could accept their individual changeover rinse water as make-up water in formulations without sacrificing product quality. This changeover reuse technique was then implement at the plant scale for selected products. Significant reductions in wastewater volume (25%) and wastewater pollutant loading (85+%) were realized as a direct result of this approach.

  9. Hard x-ray (>100 keV) imager to measure hot electron preheat for indirectly driven capsule implosions on the NIF.

    Döppner, T; Dewald, E L; Divol, L; Thomas, C A; Burns, S; Celliers, P M; Izumi, N; Kline, J L; LaCaille, G; McNaney, J M; Prasad, R R; Robey, H F; Glenzer, S H; Landen, O L

    2012-10-01

    We have fielded a hard x-ray (>100 keV) imager with high aspect ratio pinholes to measure the spatially resolved bremsstrahlung emission from energetic electrons slowing in a plastic ablator shell during indirectly driven implosions at the National Ignition Facility. These electrons are generated in laser plasma interactions and are a source of preheat to the deuterium-tritium fuel. First measurements show that hot electron preheat does not limit obtaining the fuel areal densities required for ignition and burn.

  10. Batch-batch stable microbial community in the traditional fermentation process of huyumei broad bean pastes.

    Zhu, Linjiang; Fan, Zihao; Kuai, Hui; Li, Qi

    2017-09-01

    During natural fermentation processes, a characteristic microbial community structure (MCS) is naturally formed, and it is interesting to know about its batch-batch stability. This issue was explored in a traditional semi-solid-state fermentation process of huyumei, a Chinese broad bean paste product. The results showed that this MCS mainly contained four aerobic Bacillus species (8 log CFU per g), including B. subtilis, B. amyloliquefaciens, B. methylotrophicus, and B. tequilensis, and the facultative anaerobe B. cereus with a low concentration (4 log CFU per g), besides a very small amount of the yeast Zygosaccharomyces rouxii (2 log CFU per g). The dynamic change of the MCS in the brine fermentation process showed that the abundance of dominant species varied within a small range, and in the beginning of process the growth of lactic acid bacteria was inhibited and Staphylococcus spp. lost its viability. Also, the MCS and its dynamic change were proved to be highly reproducible among seven batches of fermentation. Therefore, the MCS naturally and stably forms between different batches of the traditional semi-solid-state fermentation of huyumei. Revealing microbial community structure and its batch-batch stability is helpful for understanding the mechanisms of community formation and flavour production in a traditional fermentation. This issue in a traditional semi-solid-state fermentation of huyumei broad bean paste was firstly explored. This fermentation process was revealed to be dominated by a high concentration of four aerobic species of Bacillus, a low concentration of B. cereus and a small amount of Zygosaccharomyces rouxii. Lactic acid bacteria and Staphylococcus spp. lost its viability at the beginning of fermentation. Such the community structure was proved to be highly reproducible among seven batches. © 2017 The Society for Applied Microbiology.

  11. On-line Scheduling Of Multi-Server Batch Operations

    van der Zee, D.J.; van Harten, A.; Schuur, P.C.

    1999-01-01

    Batching jobs in a manufacturing system is a very common policy in most industries. Main reasons for batching are avoidance of setups and/or facilitation of material handling. Good examples of batch-wise production systems are ovens found in aircraft industry and in semiconductor manufacturing.

  12. On-line scheduling of multi-server batch operations

    Zee, Durk Jouke van der; Harten, Aart van; Schuur, Peter

    The batching of jobs in a manufacturing system is a very common policy in many industries. The main reasons for batching are the avoidance of setups and/or facilitation of material handling. Good examples of batch-wise production systems are the ovens that are found in the aircraft industry and in

  13. 7 CFR 58.728 - Cooking the batch.

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.728 Cooking the batch. Each batch of cheese within the cooker, including the optional...

  14. 40 CFR 63.1408 - Aggregate batch vent stream provisions.

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Aggregate batch vent stream provisions... § 63.1408 Aggregate batch vent stream provisions. (a) Emission standards. Owners or operators of aggregate batch vent streams at a new or existing affected source shall comply with either paragraph (a)(1...

  15. Demonstration of sulfur solubility determinations in high waste loading, low-activity waste glasses

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-25

    A method recommended by Pacific Northwest National Laboratory (PNNL) for sulfate solubility determinations in simulated low-activity waste glasses was demonstrated using three compositions from a recent Hanford high waste loading glass study. Sodium and sulfate concentrations in the glasses increased after each re-melting step. Visual observations of the glasses during the re-melting process reflected the changes in composition. The measured compositions showed that the glasses met the targeted values. The amount of SO3 retained in the glasses after washing was relatively high, ranging from 1.6 to 2.6 weight percent (wt %). Measured SnO2 concentrations were notably low in all of the study glasses. The composition of the wash solutions should be measured in future work to determine whether SnO2 is present with the excess sulfate washed from the glass. Increases in batch size and the amount of sodium sulfate added did not have a measureable impact on the amount of sulfate retained in the glass, although this was tested for only a single glass composition. A batch size of 250 g and a sodium sulfate addition targeting 7 wt %, as recommended by PNNL, will be used in future experiments.

  16. Influence of pre-heating on the surface modification of powder-metallurgy processed cold-work tool steel during laser surface melting

    Šturm, Roman, E-mail: roman.sturm@fs.uni-lj.si [University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana (Slovenia); Štefanikova, Maria [University of Ljubljana, Faculty of Mechanical Engineering, Aškerčeva 6, 1000 Ljubljana (Slovenia); Steiner Petrovič, Darja [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia)

    2015-01-15

    Graphical abstract: - Highlights: • Heat-treatment protocol for laser surface melting of cold-work tool steel is proposed. • The laser melted steel surface is hardened, and morphologically modified. • The pre-heating of substrate creates a crack-and pore-free steel surface. • The optimum pre-heating temperature is determined to be 350 °C. • Using pre-heating the quantity of retained austenite is reduced. - Abstract: In this study we determine the optimal parameters for surface modification using the laser surface melting of powder-metallurgy processed, vanadium-rich, cold-work tool steel. A combination of steel pre-heating, laser surface melting and a subsequent heat treatment creates a hardened and morphologically modified surface of the selected high-alloy tool steel. The pre-heating of the steel prior to the laser surface melting ensures a crack- and pore-free modified surface. Using a pre-heating temperature of 350 °C, the extremely fine microstructure, which typically evolves during the laser-melting, became slightly coarser and the volume fraction of retained austenite was reduced. In the laser-melted layer the highest values of microhardness were achieved in the specimens where a subsequent heat treatment at 550 °C was applied. The performed thermodynamic calculations were able to provide a very valuable assessment of the liquidus temperature and, especially, a prediction of the chemical composition as well as the precipitation and dissolution sequence for the carbides.

  17. Research report for fiscal 1998. Basic research for promoting joint implementation of energy use rationalization in Chinese steel industry (examination of introduction of scrap preheating system for electric furnaces); 1998 nendo chosa hokokusho. Chugoku tekkogyo ni okeru energy no shiyo gorika (denkiro scrap yonetsu system donyu kento)

    NONE

    1999-03-01

    Investigations are conducted on a project of introducing a scrap preheating system based on the central insertion movable shaft design into China's electric furnaces for the sake of energy saving and global warming gas reduction. Of the electric furnaces numbering approximately 3400 now in operation in China, most are small and antiquated, and are extremely low in energy efficiency when in operation. The percentage of electricity supplied by coal-fired facilities is high, and this causes the CO2 reduction problem. Investigations are conducted into four steel mills operating electric furnaces, and examinations are made on the applicability of a preheating system, which is the ultimate batch system developed by Nippon Steel Corporation. Studies are conducted for Wuyang Iron and Steel Co., Ltd., Tianjin Steel Pipe Co., Ltd., Budong Iron and Steel Co., Ltd., and Shanghai Five Steel Co., Ltd., and it is found that greenhouse gas will be reduced by 31,000 tons, 21,000 tons, 13,000 tons, and 11,000-tons at the said mills, respectively. It is learned that the cost to be invested will be retrieved in approximately 2.5 years, 2.8 years, 7.7 years, and 8.0 years, respectively. It is concluded that Shanghai Budong Iron and Steel (Group) Co., Ltd., is the best candidate to be equipped with the above-said system. (NEDO)

  18. Energy, exergy, environmental and economic analysis of industrial fired heaters based on heat recovery and preheating techniques

    Shekarchian, M.; Zarifi, F.; Moghavvemi, M.; Motasemi, F.; Mahlia, T.M.I.

    2013-01-01

    Highlights: • 4-E analysis of a typical industrial grade fired heater unit is studied. • This analysis is accomplished for the first time in this study. • Heat recovery and air preheating lead to substantial reduction in the fuel consumption. • The company’s current costs are tremendously reduced by these methods. • The methods lead to mitigation in GHG emission and to reduction in the associated taxes. - Abstract: Fired heaters are ubiquitous in both the petroleum and petrochemical industries, due to it being vital in their day to day operations. They form major components in petroleum refineries, petrochemical facilities, and processing units. This study was commissioned in order to analyze the economic benefits of incorporating both heat recovery and air preheating methods into the existing fired heater units. Four fired heater units were analyzed from the energy and environmental point of views. Moreover, the second law efficiency and the rate of irreversibility were also analyzed via the exergy analysis. Both analyses was indicative of the fact that the heat recovery process enhances both the first and second law efficiencies while simultaneously assisting in the production of high and low pressure water steam. The implementation and usage of the process improves the thermal and exergy efficiencies from 63.4% to 71.7% and 49.4%, to 54.8%, respectively. Additionally, the heat recovery and air preheating methods leads to a substantial reduction in fuel consumption, in the realm of up to 7.4%, while also simultaneously decreasing heat loss and the irreversibility of the unit. Nevertheless, the results of the economic analysis posits that although utilizing an air preheater unit enhances the thermal performance of the system, due to the air preheater’s capital and maintenance costs, incorporating an air preheater unit to an existing fired heater is not economically justifiable. Furthermore, the results of the sensitivity analysis and payback period

  19. Response variation in a batch of TLDS

    Burrage, J.; Campbell, A.

    2004-01-01

    Full text: At Royal Perth Hospital, LiF thermoluminescent dosimeter rods (TLDs) are handled in batches of 50. Rods in each batch are always annealed together to ensure the same thermal history and an individual batch is used with the same type and energy of radiation. A subset of a batch is used for calibration purposes by exposing them to a range of known doses and their output is used to calculate the dose received by other rods used for a dose measurement. Variation in TLD response is addressed by calculating 95% certainty levels from the calibration rods and applying this to the dose measurement rods. This approach relies on the sensitivity of rods within each batch being similar. This work investigates the validity of this assumption and considers possible benefits of applying individual rod sensitivities. The variation in response of TLD rods was assessed using 25 TLD-100 rods (Harshaw/Bicron) which were uniformly exposed to 1 Gy using 6 MeV photons in a linear accelerator on 5 separate occasions. Rods were read with a Harshaw 5500 reader. During the read process the Harshaw reader periodically checks for noise and PMT gain drift and the data were corrected for these parameters. Replicate exposure data were analysed using 1-way Analysis of Variance (ANOVA) to determine whether the between rod variations were significantly different to the variations within a single rod. A batch of 50 rods was also exposed on three occasions using the above technique. Individual TLD rod sensitivity values were determined using the rod responses from 2 exposures and these values were applied to correct charges on a rod-by-rod basis for the third exposure. ANOVA results on the 5 exposures of 25 rods showed the variance between rods was significantly greater than the within rod variance (p < 0.001). The precision of an individual rod was estimated to have a standard deviation of 2.8%. This suggests that the 95% confidence limits for repeated measurements using the same dose and

  20. BATCH-GE: Batch analysis of Next-Generation Sequencing data for genome editing assessment

    Boel, Annekatrien; Steyaert, Woutert; De Rocker, Nina; Menten, Björn; Callewaert, Bert; De Paepe, Anne; Coucke, Paul; Willaert, Andy

    2016-01-01

    Targeted mutagenesis by the CRISPR/Cas9 system is currently revolutionizing genetics. The ease of this technique has enabled genome engineering in-vitro and in a range of model organisms and has pushed experimental dimensions to unprecedented proportions. Due to its tremendous progress in terms of speed, read length, throughput and cost, Next-Generation Sequencing (NGS) has been increasingly used for the analysis of CRISPR/Cas9 genome editing experiments. However, the current tools for genome editing assessment lack flexibility and fall short in the analysis of large amounts of NGS data. Therefore, we designed BATCH-GE, an easy-to-use bioinformatics tool for batch analysis of NGS-generated genome editing data, available from https://github.com/WouterSteyaert/BATCH-GE.git. BATCH-GE detects and reports indel mutations and other precise genome editing events and calculates the corresponding mutagenesis efficiencies for a large number of samples in parallel. Furthermore, this new tool provides flexibility by allowing the user to adapt a number of input variables. The performance of BATCH-GE was evaluated in two genome editing experiments, aiming to generate knock-out and knock-in zebrafish mutants. This tool will not only contribute to the evaluation of CRISPR/Cas9-based experiments, but will be of use in any genome editing experiment and has the ability to analyze data from every organism with a sequenced genome. PMID:27461955

  1. Spin glasses

    Mookerjee, Abhijit

    1976-01-01

    ''Spin glasses'', are entire class of magnetic alloys of moderate dilution, in which the magnetic atoms are far enough apart to be unlike the pure metal, but close enough so that the indirect exchange energy between them (mediated by the s-d interaction between local moments and conduction electrons) dominates all other energies. Characteristic critical phenomena displayed such as freezing of spin orientation at 'Tsub(c)' and spreading of magnetic ordering, are pointed out. Anomalous behaviour, associated with these critical phenomena, as reflected in : (i) Moessbauer spectroscopy giving hyperfine splitting at Tsub(c), (ii) maxima in susceptibility and remanent magnetism, (iii) thermopower maxima and change in slope, (iv) Characteristic cusp in susceptibility and its removal by very small magnetic fields, and (v) conductivity-resistivity measurements, are discussed. Theoretical developments aimed at explaining these phenomena, in particular, the ideas from percolation and localisation theories, and the approach based on the gellations of polymers, are discussed. Finally, a new approach based on renormalisation group in disordered systems is also briefly mentioned. (K.B.)

  2. Autoadaptive Emailtest AZ90 for corrosion monitoring of glass-lined reactors

    Jean-Marie, H.

    1993-01-01

    In the Chemical and Pharmaceutical Industry, glass-lined vessels often contain very corrosive and harmful products. To prevent major problems such as batch contamination, leakages or explosions, it is important to detect as soon as possible a failure of the glass-lining. The well-known electrolytic method of detection has been improved by using a permanent comparison of a reference current passing between these electrodes and a defect in the glass-lining. This is made possible with the microprocessorized glass-guard to detect a leak rate independent of the product conductivity, to be self monitoring and to give an evaluation of the conductivity

  3. Performance and emission study of preheated Jatropha oil on medium capacity diesel engine

    Chauhan, Bhupendra Singh; Du Jun, Yong; Lee, Kum Bae [Division of Automobile and Mechanical Engineering, Kongju National University (Korea); Kumar, Naveen [Department of Mechanical Engineering, Delhi Technological University, Bawana Road, Delhi 42 (India)

    2010-06-15

    Diesel engines have proved their utility in transport, agriculture and power sector. Environmental norms and scared fossil fuel have attracted the attention to switch the energy demand to alternative energy source. Oil derived from Jatropha curcas plant has been considered as a sustainable substitute to diesel fuel. However, use of straight vegetable oil has encountered problem due to its high viscosity. The aim of present work is to reduce the viscosity of oil by heating from exhaust gases before fed to the engine, the study of effects of FIT (fuel inlet temperature) on engine performance and emissions using a dual fuel engine test rig with an appropriately designed shell and tube heat exchanger (with exhaust bypass arrangement). Heat exchanger was operated in such a way that it could give desired FIT. Results show that BTE (brake thermal efficiency) of engine was lower and BSEC (brake specific energy consumption) was higher when the engine was fueled with Jatropha oil as compared to diesel fuel. Increase in fuel inlet temperature resulted in increase of BTE and reduction in BSEC. Emissions of NO{sub x} from Jatropha oil during the experimental range were lower than diesel fuel and it increases with increase in FIT. CO (carbon monoxide), HC (hydrocarbon), CO{sub 2} (carbon dioxide) emissions from Jatropha oil were found higher than diesel fuel. However, with increase in FIT, a downward trend was observed. Thus, by using heat exchanger preheated Jatropha oil can be a good substitute fuel for diesel engine in the near future. Optimal fuel inlet temperature was found to be 80 C considering the BTE, BSEC and gaseous emissions. (author)

  4. Seawater feed reverse osmosis preheating appraisal, Part I: leading element performance

    Karameldin, A.; Saadawy, M.S.

    2006-01-01

    This paper is concerned with the seawater reverse osmosis preheating process, and presents a parametric study of the process. The basic transport equations describing the leading element are exhibited and appraised. The leading element, which governs the whole system performance, is studied and analysed. The incorporated and investigated operating parameters are the feed pressure and the temperature for different feed salt concentrations. In addition, different feed flow rates, effects on permeate flux and permeator salt rejection, together with the permeator recovery, are studied. A seawater membrane of a well-known data, for instance FT30SW380HR, is used to perform the study. The membrane water permeability coefficient K w is determined and correlated. Furthermore, the membrane salt permeability coefficient K s from the manufacturer system analysis program (ROSA) is given and discussed. The transport governing equations are programmed in a way that facilitates the achievement of a realistic parametric study. The results showed that the permeate flux increases significantly as the feed pressure increases. Also, it increases significantly as the feed salt concentration decreases, and also as the feed temperature and pressure increase. Meanwhile, the permeator salt rejection increases significantly as the feed pressure increases, and decreases significantly as the feed temperature increases. The study of the leading element of the array showed that there are constraints that must be considered, such as maximum membrane flux, maximum applied feed pressure, maximum feed flow rate and maximum feed temperature. Therefore, to attain the maximum membrane flux, the applied feed pressure must be lowered when the feed temperature is increased. In the case where the feed temperature is increased from 18 deg.. C to 45 deg.. C, a pressure saving of between 7% and 26% is achieved, according to the feed salt concentration and feed flow rate. (author)

  5. Production of ethanol in batch and fed-batch fermentation of soluble sugar

    Chaudhary, M.Y.; Shah, M.A.; Shah, F.H.

    1991-01-01

    Keeping in view of the demand and need for alternate energy source, especially liquid fuels and the availability of raw materials in Pakistan, we have carried out biochemical and technological studies for ethanol through fermentation of renewable substrates. Molasses and sugar cane have been used as substrate for yeast fermentation. Selected yeast were used in both batch and semi continuous fermentation of molasses. Clarified dilute molasses were fermented with different strains of Saccharomyces cerevisiae. Ethanol concentration after 64 hours batch fermentation reached 9.4% with 90% yield based on sugar content. During feed batch system similar results were obtained after a fermentation cycle of 48 hours resulting in higher productivity. Similarly carbohydrates in fruit juices and hydro lysates of biomass can be economically fermented to ethanol to be used as feed stock for other chemicals. (author)

  6. Passing in Command Line Arguments and Parallel Cluster/Multicore Batching in R with batch.

    Hoffmann, Thomas J

    2011-03-01

    It is often useful to rerun a command line R script with some slight change in the parameters used to run it - a new set of parameters for a simulation, a different dataset to process, etc. The R package batch provides a means to pass in multiple command line options, including vectors of values in the usual R format, easily into R. The same script can be setup to run things in parallel via different command line arguments. The R package batch also provides a means to simplify this parallel batching by allowing one to use R and an R-like syntax for arguments to spread a script across a cluster or local multicore/multiprocessor computer, with automated syntax for several popular cluster types. Finally it provides a means to aggregate the results together of multiple processes run on a cluster.

  7. FRIT DEVELOPMENT FOR HIGH LEVEL WASTE SLUDGE BATCH 5: COMPOSITIONAL TRENDS FOR VARYING ALUMINUM CONCENTRATIONS

    Fox, K; Tommy Edwards; David Best; Irene Reamer; Phyllis Workman

    2008-08-28

    The objective of this study was to experimentally measure the properties and performance of a series of glasses with compositions that could represent Sludge Batch 5 (SB5) as processed at the Defense Waste Processing Facility (DWPF). The data was used to provide recommendations to the Liquid Waste Organization (LWO) regarding blending and washing strategies in preparing SB5 based on acceptability of the glass compositions. These data were also used to guide frit optimization efforts as the SB5 composition was finalized. Glass compositions for this study were developed by combining a series of SB5 composition projections with a group of frits. Three composition projections for SB5 were developed using a model-based approach at Savannah River National Laboratory (SRNL). These compositions, referred to as SB5 Cases B, C and D, projected removal of 25, 50 and 75% (respectively) of the aluminum in Tank 51 through the low temperature aluminum dissolution process. The frits for this study (Frits 530 through 537) were selected based on their predicted operating windows (i.e., ranges of waste loadings over which the predicted properties of the glasses were acceptable) and their potential (based on historical trends) to provide acceptable melt rates for SB5. Six additional glasses were designed to evaluate alternatives for uranium in DWPF-type glasses used for variability studies and some scoping studies. Since special measures are necessary when working with uranium-containing glasses in the laboratory, it is desirable as a cost and time saving measure to find an alternative for uranium to support frit optimization efforts. Hafnium and neodymium were investigated as potential surrogates for uranium, and other glasses were made by simply excluding the radioactive components and renormalizing the glass composition. The study glasses were fabricated and characterized at SRNL. Chemical composition analyses suggested only minor difficulties in meeting the targeted compositions

  8. FRIT DEVELOPMENT FOR HIGH LEVEL WASTE SLUDGE BATCH 5: COMPOSITIONAL TRENDS FOR VARYING ALUMINUM CONCENTRATIONS

    Fox, K; Tommy Edwards; David Best; Irene Reamer; Phyllis Workman

    2008-01-01

    The objective of this study was to experimentally measure the properties and performance of a series of glasses with compositions that could represent Sludge Batch 5 (SB5) as processed at the Defense Waste Processing Facility (DWPF). The data was used to provide recommendations to the Liquid Waste Organization (LWO) regarding blending and washing strategies in preparing SB5 based on acceptability of the glass compositions. These data were also used to guide frit optimization efforts as the SB5 composition was finalized. Glass compositions for this study were developed by combining a series of SB5 composition projections with a group of frits. Three composition projections for SB5 were developed using a model-based approach at Savannah River National Laboratory (SRNL). These compositions, referred to as SB5 Cases B, C and D, projected removal of 25, 50 and 75% (respectively) of the aluminum in Tank 51 through the low temperature aluminum dissolution process. The frits for this study (Frits 530 through 537) were selected based on their predicted operating windows (i.e., ranges of waste loadings over which the predicted properties of the glasses were acceptable) and their potential (based on historical trends) to provide acceptable melt rates for SB5. Six additional glasses were designed to evaluate alternatives for uranium in DWPF-type glasses used for variability studies and some scoping studies. Since special measures are necessary when working with uranium-containing glasses in the laboratory, it is desirable as a cost and time saving measure to find an alternative for uranium to support frit optimization efforts. Hafnium and neodymium were investigated as potential surrogates for uranium, and other glasses were made by simply excluding the radioactive components and renormalizing the glass composition. The study glasses were fabricated and characterized at SRNL. Chemical composition analyses suggested only minor difficulties in meeting the targeted compositions

  9. CONVERSION OF PINEAPPLE JUICE WASTE INTO LACTIC ACID IN BATCH AND FED – BATCH FERMENTATION SYSTEMS

    Abdullah Mochamad Busairi

    2012-01-01

    Full Text Available Pineapple juice waste contains valuable components, which are mainly sucrose, glucose, and fructose. Recently, lactic acid has been considered to be an important raw material for the production of biodegradable lactide polymer. The fermentation experiments were carried out in a 3 litres fermentor (Biostat B Model under anaerobic condition with stirring speed of 50 rpm, temperature at 40oC, and pH of 6.00. Effect of feed concentration on lactic acid production, bacterial growth, substrate utilisation and productivity was studied. The results obtained from fed- batch culture fermentation showed that the maximum lactic acid productivity was 0.44 g/L.h for feed concentration of 90 g/L at 48 hours. Whereas the lactic acid productivity obtained from fed-batch culture was twice and half fold higher than that of batch culture productivity.  Buangan jus nanas mengandung komponen yang berharga terutama sukrosa, glukosa, dan fruktosa. Asam laktat adalah bahan baku yang terbaru dan penting untuk dibuat sebagai polimer laktat yang dapat terdegradasi oleh lingkungan. Percobaan dilakukan pada fermentor 3 liter (Model Biostat B di bawah kondisi anaerob dengan kecepatan pengadukan 50 rpm, temperatur 40oC, dan pH 6,00. Pengaruh konsentrasi umpan terhadap produksi asam laktat, pertumbuhan mikroba, pengggunaan substrat dan produktivitas telah dipelajari. Hasil yang didapatkan pada fermentasi dengan menggunakan sistem fed-batch menunjukkan bahwa produktivitas asam laktat maksimum adalah 0.44 g/L,jam dengan konsentrasi umpan, 90 g/L pada waktu 48 jam. Bahkan produktivitas asam laktat yang didapat pada kultur fed-batch lebih tinggi 2,5 kali dari pada proses menggunakan sistem batch

  10. Lead extraction from Cathode Ray Tube (CRT) funnel glass: Reaction mechanisms in thermal reduction with addition of carbon (C).

    Lu, Xingwen; Ning, Xun-An; Chen, Da; Chuang, Kui-Hao; Shih, Kaimin; Wang, Fei

    2018-06-01

    This study quantitatively determined the extraction of lead from CRT funnel glass and examined the mechanisms of thermally reducing lead in the products of sintering Pb-glass with carbon in the pre-heated furnace. The experimentally derived results indicate that a 90.3 wt% lead extraction efficiency can be achieved with 20 wt% of C addition at 950 °C for 3 min under air. The formation of viscous semi-liquid glass blocked the oxygen supply between the interaction of C and Pb-glass, and was highly effective for the extraction of metallic Pb. A maximum of 87.3% lead recover was obtained with a C to Na 2 CO 3 ratio of 1/3 at 1200 °C. The decrease of C/Na 2 CO 3 ratio enhanced the metallic lead recovery by increasing the glass viscosity for effective sedimentation of metallic lead in the bottom. However, with the further increase of temperature and treatment time, re-vitrification of lead back to silicate-glass matrix was detected in both Pb-glass/C and Pb-glass/C/Na 2 CO 3 systems. The findings indicated that with proper controls, using C as an inexpensive reagent can effectively reduce treatment time and energy, which is crucial to a waste-to-resource technology for economically recovering lead from the waste CRT glass. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. Sojourn time distributions in a Markovian G-queue with batch arrival and batch removal

    Yang Woo Shin

    1999-01-01

    Full Text Available We consider a single server Markovian queue with two types of customers; positive and negative, where positive customers arrive in batches and arrivals of negative customers remove positive customers in batches. Only positive customers form a queue and negative customers just reduce the system congestion by removing positive ones upon their arrivals. We derive the LSTs of sojourn time distributions for a single server Markovian queue with positive customers and negative customers by using the first passage time arguments for Markov chains.

  12. Cadmium removal using Cladophora in batch, semi-batch and flow reactors.

    Sternberg, Steven P K; Dorn, Ryan W

    2002-02-01

    This study presents the results of using viable algae to remove cadmium from a synthetic wastewater. In batch and semi-batch tests, a local strain of Cladophora algae removed 80-94% of the cadmium introduced. The flow experiments that followed were conducted using non-local Cladophora parriaudii. Results showed that the alga removed only 12.7(+/-6.4)% of the cadmium introduced into the reactor. Limited removal was the result of insufficient algal quantities and poor contact between the algae and cadmium solution.

  13. Sinter recrystalization and properties evaluation of glass-ceramic from waste glass bottle and magnesite for extended application

    As'mau Ibrahim Gebi

    2016-12-01

    Full Text Available In a bid to address environmental challenges associated with the management of waste Coca cola glass bottle, this study set out to develop glass ceramic materials using waste coca cola glass bottles and magnesite from Sakatsimta in Adamawa state. A reagent grade chrome (coloring agent were used to modify the composition of the coca cola glass bottle;  X-ray fluorescence(XRF, X-ray diffraction (XRD and Thermo gravimetric analysis (TGA were used to characterize raw materials, four batches GC-1= Coca cola glass frit +1%Cr2O3, GC-2=97% Coca cola glass frit+ 2% magnesite+1%Cr2O3, GC-3=95% Coca cola glass frit+ 4%magnesite+1%Cr2O3, GC-4=93%Coca cola glass frit+ 6%magnesite+ 1%Cr2O3 were formulated and prepared. Thermal Gradient Analysis (TGA results were used as a guide in selection of three temperatures (7000C, 7500C and 8000C used for the study, three particle sizes -106+75, -75+53, -53µm and 2 hr sintering time were also used, the sinter crystallization route of glass ceramic production was adopted. The samples were characterized by X-ray diffraction (XRD and Scanning Electron Microscope (SEM, the density, porosity, hardness and flexural strength of the resulting glass ceramics were also measured. The resulting glass ceramic materials composed mainly of wollastonite, diopside and anorthite phases depending on composition as indicated by XRD and SEM, the density of the samples increased with increasing sintering temperature and decreasing particle size. The porosity is minimal and it decreases with increasing sintering temperature and decreasing particle size. The obtained glass ceramic materials possess appreciable hardness and flexural strength with GC-3 and GC-4 having the best combination of both properties.

  14. Actual Waste Demonstration of the Nitric-Glycolic Flowsheet for Sludge Batch 9 Qualification

    Newell, J. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pareizs, J. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martino, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Reboul, S. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coleman, C. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Johnson, F. C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-09-01

    For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs qualification testing to demonstrate that the sludge batch is processable. Testing performed by the Savannah River National Laboratory has shown glycolic acid to be effective in replacing the function of formic acid in the DWPF chemical process. The nitric-glycolic flowsheet reduces mercury, significantly lowers the catalytic generation of hydrogen and ammonia which could allow purge reduction in the Sludge Receipt and Adjustment Tank (SRAT), stabilizes the pH and chemistry in the SRAT and the Slurry Mix Evaporator (SME), allows for effective rheology adjustment, and is favorable with respect to melter flammability. In order to implement the new flowsheet, SRAT and SME cycles, designated SC-18, were performed using a Sludge Batch (SB) 9 slurry blended from SB8 Tank 40H and Tank 51H samples. The SRAT cycle involved adding nitric and glycolic acids to the sludge, refluxing to steam strip mercury, and dewatering to a targeted solids concentration. Data collected during the SRAT cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. The SME cycle demonstrated the addition of glass frit and the replication of six canister decontamination additions. The demonstration concluded with dewatering to a targeted solids concentration. Data collected during the SME cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. Slurry and condensate samples were collected for subsequent analysis

  15. Sludge Batch 7B Qualification Activities With SRS Tank Farm Sludge

    Pareizs, J.; Click, D.; Lambert, D.; Reboul, S.

    2011-01-01

    Waste Solidification Engineering (WSE) has requested that characterization and a radioactive demonstration of the next batch of sludge slurry - Sludge Batch 7b (SB7b) - be completed in the Shielded Cells Facility of the Savannah River National Laboratory (SRNL) via a Technical Task Request (TTR). This characterization and demonstration, or sludge batch qualification process, is required prior to transfer of the sludge from Tank 51 to the Defense Waste Processing Facility (DWPF) feed tank (Tank 40). The current WSE practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks. Discharges of nuclear materials from H Canyon are often added to Tank 51 during sludge batch preparation. The sludge is washed and transferred to Tank 40, the current DWPF feed tank. Prior to transfer of Tank 51 to Tank 40, SRNL typically simulates the Tank Farm and DWPF processes with a Tank 51 sample (referred to as the qualification sample). With the tight schedule constraints for SB7b and the potential need for caustic addition to allow for an acceptable glass processing window, the qualification for SB7b was approached differently than past batches. For SB7b, SRNL prepared a Tank 51 and a Tank 40 sample for qualification. SRNL did not receive the qualification sample from Tank 51 nor did it simulate all of the Tank Farm washing and decanting operations. Instead, SRNL prepared a Tank 51 SB7b sample from samples of Tank 7 and Tank 51, along with a wash solution to adjust the supernatant composition to the final SB7b Tank 51 Tank Farm projections. SRNL then prepared a sample to represent SB7b in Tank 40 by combining portions of the SRNL-prepared Tank 51 SB7b sample and a Tank 40 Sludge Batch 7a (SB7a) sample. The blended sample was 71% Tank 40 (SB7a) and 29% Tank 7/Tank 51 on an insoluble solids basis. This sample is referred to as the SB7b Qualification Sample. The blend represented the highest projected Tank 40 heel (as of May 25, 2011), and thus, the highest

  16. Reconfirmation of frit 803 based on the January 2016 sludge batch 9 reprojection

    Johnson, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-02-10

    On January 11, 2016, Savannah River Remediation (SRR) provided the Savannah River National Laboratory (SRNL) with a Sludge Batch 9 (SB9) reprojection that was developed from the analyzed composition of a Tank 51 sample. This sample was collected after field washing had been completed in Tank 51 to support the alternate reductant task. Based on this reprojection, Frit 803 is still a viable option for the processing of SB9 under sludge-only operations and coupled (Actinide Removal Process (ARP) product with and without monosodium titanate (MST)) operations. The maximum projected volumes of ARP product that can be transferred from the Precipitate Reactor Feed Tank (PRFT) per Sludge Receipt and Adjustment Tank (SRAT) batch and the resulting Na2O concentrations in the SRAT for coupled operations were determined. The Na2O concentrations in the SRAT resulting from the maximum projected ARP product transfer volumes are consistent with those from the previous assessments that were based on the August 2015 projections. Regardless of the presence or absence of MST in the ARP product, the contribution of Na2O to the resulting glass will be similar at the same waste loading (WL). These projected volumes of ARP product are not anticipated to be an issue for SB9. The actual transfer volumes from the PRFT to the SRAT are determined based upon the analyzed Na2O concentrations in the PRFT samples, which has resulted in larger transfer volumes than those allowed by the projections for Sludge Batch 8 (SB8). An operating window of 32-40% WL around the nominal WL of 36% is achievable for both sludge-only and coupled operations; however, each of the glass systems studied does become limited by waste form affecting constraints (durability) at higher volumes of ARP product and WLs of 41-42%.

  17. lead glass brick

    When you look through the glass at a picture behind, the picture appears raised up because light is slowed down in the dense glass. It is this density (4.06 gcm-3) that makes lead glass attractive to physicists. The refractive index of the glass is 1.708 at 400nm (violet light), meaning that light travels in the glass at about 58% its normal speed. At CERN, the OPAL detector uses some 12000 blocks of glass like this to measure particle energies.

  18. Glass forms for immobilization of Hanford wastes

    Schulz, W.W.; Dressen, A.L.; Hobbick, C.W.; Babad, H.

    1975-03-01

    Approximately 140 million liters of solid salt cake (mainly NaNO 3 ), produced by evaporation of aged alkaline high-level liquid wastes, will be stored in underground tanks when the present Hanford Waste Management Program is completed in the early 1980's. At this time also, large volumes of various other solid radioactive wastes (sludges, excavated Pu-contaminated soil, and doubly encapsulated 137 CsCl and 90 SrF 2 ) will be stored on the Hanford Reservation. All these solid wastes can be converted to immobile silicate and aluminosilicate glasses of low water leachability by melting them at 1100 0 to 1400 0 C with appropriate amounts of basalt (or sand) and other glass-formers such as B 2 O 3 or CaO. Reviewed in this paper are formulations and other melt conditions used successfully in batch tests to make glasses from actual and synthetic wastes; leachability and other properties of these glasses show them to be satisfactory vehicles for immobilization of the Hanford wastes. (U.S.)

  19. Establishment of welding process without PWHT and preheating in SGV480 plate for nuclear reactor containment vessel

    Watanabe, Nozomu; Higashikubo, Tomohiro; Nagamura, Takafumi [Mitsubishi Heavy Industries. Ltd., Kobe Shipyard and Machinery Works (Japan); Yoshimoto Kentaro [Mitsubishi Heavy Industries Ltd., Takasago, Hyogo (Japan). Takasago Research and Development Center

    2000-07-01

    Ordinances of Japan's Ministry of International Trade and Industry provide that welded joints more than 38 mm thick used in nuclear reactor containment vessels undergo Post Weld Heat Treatment (PWHT). PWHT is difficult to apply in the field, however. We made SGV480 plate tougher and more weldable by using a Thermo-Mechanical Control Process (TMCP) in rolling. Such plate can be used without PWHT or preheating up to 55 mm thick at lowest service temperature -19degC. (author)

  20. MgO melting curve constraints from shock temperature and rarefaction overtake measurements in samples preheated to 2300 K

    Fat'yanov, Oleg V.; Asimow, P. D.

    2014-01-01

    Continuing our effort to obtain experimental constraints on the melting curve of MgO at 100-200 GPa, we extended our target preheating capability to 2300 K. Our new Mo capsule design holds a long MgO crystal in a controlled thermal gradient until impact by a Ta flyer launched at up to 7.5 km/s on the Caltech two-stage light-gas gun. Radiative shock temperatures and rarefaction overtake times were measured simultaneously by a 6-channel VIS/NIR pyrometer with 3 ns time resolution. The majority ...

  1. Comparative studies on the performance and emissions of a direct injection diesel engine fueled with neem oil and pumpkin seed oil biodiesel with and without fuel preheater.

    Ramakrishnan, Muneeswaran; Rathinam, Thansekhar Maruthu; Viswanathan, Karthickeyan

    2018-02-01

    In the present experimental analysis, two non-edible oils namely neem oil and pumpkin seed oil were considered. They are converted into respective biodiesels namely neem oil methyl ester (B1) and pumpkin seed oil methyl ester (B2) through transesterification process and their physical and chemical properties were examined using ASTM standards. Diesel was used as a baseline fuel in Kirloskar TV1 model direct injection four stroke diesel engine. A fuel preheater was designed and fabricated to operate at various temperatures (60, 70, and 80 °C). Diesel showed higher brake thermal efficiency (BTE) than biodiesel samples. Lower brake specific fuel consumption (BSFC) was obtained with diesel than B1 sample. B1 exhibited lower BSFC than B2 sample without preheating process. High preheating temperature (80 °C) results in lower fuel consumption for B1 sample. The engine emission characteristics like carbon monoxide (CO), hydrocarbon (HC), and smoke were found lower with B1 sample than diesel and B2 except oxides of nitrogen (NOx) emission. In preheating of fuel, B1 sample with high preheating temperature showed lower CO, HC, and smoke emission (except NOx) than B2 sample.

  2. Glass and nuclear wastes

    Sombret, C.

    1982-10-01

    Glass shows interesting technical and economical properties for long term storage of solidified radioactive wastes by vitrification or embedding. Glass composition, vitrification processes, stability under irradiation, thermal stability and aqueous corrosion are studied [fr

  3. Microstructuring of glasses

    Hülsenberg, Dagmar; Bismarck, Alexander

    2008-01-01

    As microstructured glass becomes increasingly important for microsystems technology, the main application fields include micro-fluidic systems, micro-analysis systems, sensors, micro-actuators and implants. And, because glass has quite distinct properties from silicon, PMMA and metals, applications exist where only glass devices meet the requirements. The main advantages of glass derive from its amorphous nature, the precondition for its - theoretically - direction-independent geometric structurability. Microstructuring of Glasses deals with the amorphous state, various glass compositions and their properties, the interactions between glasses and the electromagnetic waves used to modify it. Also treated in detail are methods for influencing the geometrical microstructure of glasses by mechanical, chemical, thermal, optical, and electrical treatment, and the methods and equipment required to produce actual microdevices.

  4. Measurement of optical glasses

    Nicolau-Rebigan, S.

    1978-11-01

    The possibilities of measurement of the optical glasses parameters needed in building optical devices especially in lasers devices are presented. In the first chapter the general features of the main optical glasses as well as the modalities of obtaining them are given. Chapter two defines the optical glass parameters, and the third chapter describes the measuring methods of the optical glass parameters. Finally, the conclusions which point out the utilization of this paper are presented. (author)

  5. Inorganic fouling mitigation by salinity cycling in batch reverse osmosis

    Maswadeh, Laith A.; Warsinger, David Elan Martin; Tow, Emily W.; Connors, Grace B.; Swaminathan, Jaichander; Lienhard, John H

    2018-01-01

    Enhanced fouling resistance has been observed in recent variants of reverse osmosis (RO) desalination which use time-varying batch or semi-batch processes, such as closed-circuit RO (CCRO) and pulse flow RO (PFRO). However, the mechanisms of batch processes' fouling resistance are not well-understood, and models have not been developed for prediction of their fouling performance. Here, a framework for predicting reverse osmosis fouling is developed by comparing the fluid residence time in bat...

  6. Optimizing Resource Utilization in Grid Batch Systems

    Gellrich, Andreas

    2012-01-01

    On Grid sites, the requirements of the computing tasks (jobs) to computing, storage, and network resources differ widely. For instance Monte Carlo production jobs are almost purely CPU-bound, whereas physics analysis jobs demand high data rates. In order to optimize the utilization of the compute node resources, jobs must be distributed intelligently over the nodes. Although the job resource requirements cannot be deduced directly, jobs are mapped to POSIX UID/GID according to the VO, VOMS group and role information contained in the VOMS proxy. The UID/GID then allows to distinguish jobs, if users are using VOMS proxies as planned by the VO management, e.g. ‘role=production’ for Monte Carlo jobs. It is possible to setup and configure batch systems (queuing system and scheduler) at Grid sites based on these considerations although scaling limits were observed with the scheduler MAUI. In tests these limitations could be overcome with a home-made scheduler.

  7. Sewage sludge irradiators: Batch and continuous flow

    Lavale, D.S.; George, J.R.; Shah, M.R.; Rawat, K.P.

    1998-01-01

    The potential threat to the environment imposed by high pathogenic organism content in municipal wastewater, especially the sludge and the world-wide growing aspirations for a cleaner, salubrious environment have made it mandatory for the sewage and sludge to undergo treatment, prior to their ultimate disposal to mother nature. Incapabilities associated with the conventional wastewater treatments to mitigate the problem of microorganisms have made it necessary to look for other alternatives, radiation treatment being the most reliable, rapid and environmentally sustainable of them. To promote the use of radiation for the sludge hygienization, Department of Atomic Energy has endeavoured to set up an indigenous, Sludge Hygienization Research Irradiator (SHRI) in the city of Baroda. Designed for 18.5 PBq of 60 Co to disinfect the digested sludge, the irradiator has additional provision for treatment of effluent and raw sewage. From engineering standpoint, all the subsystems have been functioning satisfactorily since its commissioning in 1990. Prolonged studies, spanning over a period of six years, primarily focused on inactivation of microorganism revealed that 3 kGy dose of gamma radiation is adequate to make the sludge pathogen and odour-free. A dose of 1.6 kGy in raw sewage and 0.5 kGy in effluent reduced coliform counts down to the regulatory discharge limits. These observations reflect a possible cost-effective solution to the burgeoning problem of surface water pollution across the globe. In the past, sub 37 PBq 60 Co batch irradiators have been designed and commissioned successfully for the treatment of sludge. Characterized with low dose delivery rates they are well-suited for treating low volumes of sludge in batches. Some concepts of continuous flow 60 Co irradiators having larger activities, yet simple and economic in design, are presented in the paper

  8. Properties of Desert Sand and CMAS Glass

    Bansal, Narottam P.; Choi, Sung R.

    2014-01-01

    As-received desert sand from a Middle East country has been characterized for its phase composition and thermal stability. X-ray diffraction analysis showed the presence of quartz (SiO2), calcite (CaCO3), gypsum (CaSO4.2H2O), and NaAlSi3O8 phases in as-received desert sand and showed weight loss of approx. 35 percent due to decomposition of CaCO3 and CaSO4.2H2O when heated to 1400 C. A batch of as-received desert sand was melted into calcium magnesium aluminosilicate (CMAS) glass at approx. 1500 C. From inductively coupled plasma-atomic emission spectrometry, chemical composition of the CMAS glass was analyzed to be 27.8CaO-4MgO-5Al2O3-61.6SiO2-0.6Fe2O3-1K2O (mole percent). Various physical, thermal and mechanical properties of the glass have been evaluated. Bulk density of CMAS glass was 2.69 g/cc, Young's modulus 92 GPa, Shear modulus 36 GPa, Poisson's ratio 0.28, dilatometric glass transition temperature (T (sub g)) 706 C, softening point (T (sub d)) 764 C, Vickers microhardness 6.3 +/- 0.4 GPa, indentation fracture toughness 0.75 +/- 0.15 MPa.m (sup 1/2), and coefficient of thermal expansion (CTE) 9.8 x 10 (exp -6)/degC in the temperature range 25 to 700 C. Temperature dependence of viscosity has also been estimated from various reference points of the CMAS glass using the Vogel-Fulcher-Tamman (VFT) equation. The glass remained amorphous after heat treating at 850 C for 10 hr but crystallized into CaSiO3 and Ca-Mg-Al silicate phases at 900 C or higher temperatures. Crystallization kinetics of the CMAS glass has also been investigated by differential thermal analysis (DTA). Activation energies for the crystallization of two different phases in the glass were calculated to be 403 and 483 kJ/mol, respectively.

  9. Mechanically reinforced glass beams

    Nielsen, Jens Henrik; Olesen, John Forbes

    2007-01-01

    laminated float glass beam is constructed and tested in four-point bending. The beam consist of 4 layers of glass laminated together with a slack steel band glued onto the bottom face of the beam. The glass parts of the tested beams are \\SI{1700}{mm} long and \\SI{100}{mm} high, and the total width of one...

  10. Radionuclide decay effects on waste glass corrosion and weathering

    Wronkiewicz, D.J.

    1993-01-01

    The release of glass components into solution, including radionuclides, may be influenced by the presence of radiolytically produced nitric acid, carboxylic acid, and transient water dissociation products such as ·OH and O 2 - . Under batch test conditions, glass corrosion has been shown to increase up to a maximum of three-to five-fold in irradiated tests relative to nonirradiated tests, while in other studies the presence of radiolytic products has actually decreased glass corrosion rates. Bicarbonate groundwaters will buffer against pH decreases and changes in corrosion rates. Under high surface area-to-solution volume (S/V) conditions, the bicarbonate buffering reservoir may be quickly overwhelmed by radiolytic acids that are concentrated in the thin films of water contacting the samples. Glass reaction rates have been shown to increase up to 10-to-15-fold due to radiation exposure under high S/V conditions. Radiation damage to solid glass materials results in bond damage and atomic displacements. This type of damage has been shown to increase the release rates of glass components up to four-fold during subsequent corrosion tests, although under actual disposal conditions, glass annealing processes may negate the solid radiation damage effects

  11. Effect of preheating on the damage to tungsten targets after repetitive ITER ELM-like heat loads

    Makhlay, V A [Institute of Plasma Physics of the NSC KIPT 1, Akademicheskaya, 61108 Kharkov (Ukraine); Bandura, A N [Institute of Plasma Physics of the NSC KIPT 1, Akademicheskaya, 61108 Kharkov (Ukraine); Byrka, O V [Institute of Plasma Physics of the NSC KIPT 1, Akademicheskaya, 61108 Kharkov (Ukraine); Garkusha, I E [Institute of Plasma Physics of the NSC KIPT 1, Akademicheskaya, 61108 Kharkov (Ukraine); Chebotarev, V V [Institute of Plasma Physics of the NSC KIPT 1, Akademicheskaya, 61108 Kharkov (Ukraine); Tereshin, V I [Institute of Plasma Physics of the NSC KIPT 1, Akademicheskaya, 61108 Kharkov (Ukraine); Landman, I [Forschungszentrum Karlsruhe, IHM, 76021 Karlsruhe (Germany)

    2007-03-15

    The behaviour of a preheated tungsten target under repetitive pulsed plasma impacts of the energy density 0.75 MJ m{sup -2} with the pulse duration of 0.25 ms was studied with the quasi-stationary plasma accelerator (QSPA) Kh-50. Two identical samples of pure sintered tungsten have been exposed to numbers of pulses exceeding 100. One sample was maintained at room temperature and the other sample preheated at 650 deg. C. The experiments demonstrated that on the cold surface some macro-cracks dominate, but on the hot surface they do not develop. However, in both cases some fine meshes of micro-cracks are observed. With increasing the number of exposures, the width of the micro-cracks gradually increases, achieving 0.8-1.5 {mu}m after 100 pulses. In addition, the SEM shows some cellular structure with the cell sizes about 0.3 {mu}m, and after large numbers of exposures some blisters of sizes up to 100-150 {mu}m appear.

  12. MgO melting curve constraints from shock temperature and rarefaction overtake measurements in samples preheated to 2300 K

    Fat'yanov, O. V.; Asimow, P. D.

    2014-05-01

    Continuing our effort to obtain experimental constraints on the melting curve of MgO at 100-200 GPa, we extended our target preheating capability to 2300 K. Our new Mo capsule design holds a long MgO crystal in a controlled thermal gradient until impact by a Ta flyer launched at up to 7.5 km/s on the Caltech two-stage light-gas gun. Radiative shock temperatures and rarefaction overtake times were measured simultaneously by a 6-channel VIS/NIR pyrometer with 3 ns time resolution. The majority of our experiments showed smooth monotonic increases in MgO sound speed and shock temperature with pressure from 197 to 243 GPa. The measured temperatures as well as the slopes of the pressure dependences for both temperature and sound speed were in good agreement with those calculated numerically for the solid phase at our peak shock compression conditions. Most observed sound speeds, however, were ~800 m/s higher than those predicted by the model. A single unconfirmed data point at 239 GPa showed anomalously low temperature and sound speed, which could both be explained by partial melting in this experiment and could suggest that the Hugoniot of MgO preheated to 2300 K crosses its melting line just slightly above 240 GPa.

  13. MgO melting curve constraints from shock temperature and rarefaction overtake measurements in samples preheated to 2300 K

    Fat'yanov, O V; Asimow, P D

    2014-01-01

    Continuing our effort to obtain experimental constraints on the melting curve of MgO at 100-200 GPa, we extended our target preheating capability to 2300 K. Our new Mo capsule design holds a long MgO crystal in a controlled thermal gradient until impact by a Ta flyer launched at up to 7.5 km/s on the Caltech two-stage light-gas gun. Radiative shock temperatures and rarefaction overtake times were measured simultaneously by a 6-channel VIS/NIR pyrometer with 3 ns time resolution. The majority of our experiments showed smooth monotonic increases in MgO sound speed and shock temperature with pressure from 197 to 243 GPa. The measured temperatures as well as the slopes of the pressure dependences for both temperature and sound speed were in good agreement with those calculated numerically for the solid phase at our peak shock compression conditions. Most observed sound speeds, however, were ∼800 m/s higher than those predicted by the model. A single unconfirmed data point at 239 GPa showed anomalously low temperature and sound speed, which could both be explained by partial melting in this experiment and could suggest that the Hugoniot of MgO preheated to 2300 K crosses its melting line just slightly above 240 GPa.

  14. Preliminary studies of using preheated carrier gas for on-line membrane extraction of semivolatile organic compounds.

    Liu, Xinyu; Pawliszyn, Janusz

    2007-04-01

    In this paper, we present results for the on-line determination of semivolatile organic compounds (SVOCs) in air using membrane extraction with a sorbent interface-ion mobility spectrometry (MESI-IMS) system with a preheated carrier (stripping) gas. The mechanism of the mass transfer of SVOCs across a membrane was initially studied. In comparison with the extraction of volatile analytes, the mass transfer resistance that originated from the slow desorption from the internal membrane surface during the SVOC extraction processes should be taken into account. A preheated carrier gas system was therefore built to facilitate desorption of analytes from the internal membrane surface. With the benefit of a temperature gradient existing between the internal and external membrane surfaces, an increase in the desorption rate of a specific analyte at the internal surface and the diffusion coefficient within the membrane could be achieved while avoiding a decrease of the distribution constant on the external membrane interface. This technique improved both the extraction rate and response times of the MESI-IMS system for the analysis of SVOCs. Finally, the MESI-IMS system was shown to be capable of on-site measurement by monitoring selected polynuclear aromatic hydrocarbons emitted from cigarette smoke.

  15. Hydrodynamic and thermal mechanisms of filtration combustion inclinational instability based on non-uniform distribution of initial preheating temperature

    Xia, Yongfang; Shi, Junrui; Xu, Youning; Ma, Rui

    2018-03-01

    Filtration combustion (FC) is one style of porous media combustion with inert matrix, in which the combustion wave front propagates, only downstream or reciprocally. In this paper, we investigate the FC flame front inclinational instability of lean methane/air mixtures flowing through a packed bed as a combustion wave front perturbation of the initial preheating temperature non-uniformity is assumed. The predicted results show that the growth rate of the flame front inclinational angle is proportional to the magnitude of the initial preheating temperature difference. Additionally, depending on gas inlet gas velocity and equivalence ratio, it is demonstrated that increase of gas inlet gas velocity accelerates the FC wave front deformation, and the inclinational instability evolves faster at lower equivalence ratio. The development of the flame front inclinational angle may be regarded as a two-staged evolution, which includes rapid increase, and approaching maximum value of inclinational angle due to the quasi-steady condition of the combustion system. The hydrodynamic and thermal mechanisms of the FC inclinational instability are analyzed. Consequently, the local propagation velocity of the FC wave front is non-uniform to result in the development of inclinational angle at the first stage of rapid increase.

  16. Measurement of Preheat and Shock Melting in Be Ablators During the First Few ns of the NIF Ignition Pulse

    Bradley, D K; Prisbrey, S T; Page, R H; Braun, D G; Edwards, M J; Hibbard, R L; Moreno, K A; Mauldin, M P; Nikroo, A

    2008-05-28

    We have developed a scaled hohlraum platform to experimentally measure preheat in ablator materials during the first few nanoseconds of the radiation drive proposed for ignition experiments at the National Ignition Facility [J. A. Paisner, J. D. Boyes, S. A. Kumpan, et al., Laser Focus World 30, 75 (1994)]. The platform design approximates the radiation environment of the pole of the capsule by matching both the laser spot intensity and illuminated hohlraum wall fraction in scaled halfraums driven by the OMEGA laser system [T. R. Boehly, D. L. Brown, R. S. Craxton, et al., Optics Communications 133, 495 (1997)]. A VISAR reflecting from the rear surface of the sample was used to measure sample motion prior to shock breakout. The experiments show that the first {approx}20 {micro}m of a Be ablator will be melted by radiation preheat, with subsequent material melted by the initial shock, in agreement with simulations. The experiments also show no evidence of anomalous heating of buried high-z doped layers in the ablator.

  17. A totally heat-integrated distillation column (THIDiC) - the effect of feed pre-heating by distillate

    Huang Kejin [School of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China)], E-mail: huangkj@mail.buct.edu.cn; Shan Lan; Zhu Qunxiong [School of Information Science and Technology, Beijing University of Chemical Technology, Beijing 100029 (China); Qian Jixin [School of Information Science and Technology, Zhejiang University, Zhejiang 300027 (China)

    2008-06-15

    An ideal heat-integrated distillation column (ideal HIDiC) is characterized by external zero-reflux and zero-reboil ratio operation. Since the distillate is a high-pressure vapor phase flow, it can be used to pre-heat the feed to be separated, thereby giving rise to a totally heat-integrated distillation column (THIDiC). Although the THIDiC is more thermodynamically efficient than the ideal HIDiC, it is found that the heat integration between the distillate and feed turns it into an open-loop integrating process and poses additional difficulties to process operation. Therefore, a careful decision must be made on the selection between the ideal HIDiC and the THIDiC during process development. In this paper, separation of a binary equimolar mixture of benzene and toluene is selected as an illustrative example. Both process design and operability analysis are conducted, with special emphasis focused on the characteristics of feed pre-heating with distillate. The results obtained show deep insight into the design and operation of the THIDiC.

  18. A totally heat-integrated distillation column (THIDiC) - the effect of feed pre-heating by distillate

    Huang Kejin; Shan Lan; Zhu Qunxiong; Qian Jixin

    2008-01-01

    An ideal heat-integrated distillation column (ideal HIDiC) is characterized by external zero-reflux and zero-reboil ratio operation. Since the distillate is a high-pressure vapor phase flow, it can be used to pre-heat the feed to be separated, thereby giving rise to a totally heat-integrated distillation column (THIDiC). Although the THIDiC is more thermodynamically efficient than the ideal HIDiC, it is found that the heat integration between the distillate and feed turns it into an open-loop integrating process and poses additional difficulties to process operation. Therefore, a careful decision must be made on the selection between the ideal HIDiC and the THIDiC during process development. In this paper, separation of a binary equimolar mixture of benzene and toluene is selected as an illustrative example. Both process design and operability analysis are conducted, with special emphasis focused on the characteristics of feed pre-heating with distillate. The results obtained show deep insight into the design and operation of the THIDiC

  19. Fluoride glass fiber optics

    Aggarwal, Ishwar D

    1991-01-01

    Fluoride Glass Fiber Optics reviews the fundamental aspects of fluoride glasses. This book is divided into nine chapters. Chapter 1 discusses the wide range of fluoride glasses with an emphasis on fluorozirconate-based compositions. The structure of simple fluoride systems, such as BaF2 binary glass is elaborated in Chapter 2. The third chapter covers the intrinsic transparency of fluoride glasses from the UV to the IR, with particular emphasis on the multiphonon edge and electronic edge. The next three chapters are devoted to ultra-low loss optical fibers, reviewing methods for purifying and

  20. Multiple Glass Ceilings

    Russo, Giovanni; Hassink, Wolter

    2011-01-01

    Both vertical (between job levels) and horizontal (within job levels) mobility can be sources of wage growth. We find that the glass ceiling operates at both margins. The unexplained part of the wage gap grows across job levels (glass ceiling at the vertical margin) and across the deciles of the intra-job-level wage distribution (glass ceiling at the horizontal margin). This implies that women face many glass ceilings, one for each job level above the second, and that the glass ceiling is a p...

  1. Homogeneity of Inorganic Glasses

    Jensen, Martin; Zhang, L.; Keding, Ralf

    2011-01-01

    Homogeneity of glasses is a key factor determining their physical and chemical properties and overall quality. However, quantification of the homogeneity of a variety of glasses is still a challenge for glass scientists and technologists. Here, we show a simple approach by which the homogeneity...... of different glass products can be quantified and ranked. This approach is based on determination of both the optical intensity and dimension of the striations in glasses. These two characteristic values areobtained using the image processing method established recently. The logarithmic ratio between...

  2. Experimental study on the operating characteristics of an inner preheating transpiring wall reactor for supercritical water oxidation: Temperature profiles and product properties

    Zhang, Fengming; Xu, Chunyan; Zhang, Yong; Chen, Shouyan; Chen, Guifang; Ma, Chunyuan

    2014-01-01

    A new process to generate multiple thermal fluids by supercritical water oxidation (SCWO) was proposed to enhance oil recovery. An inner preheating transpiring wall reactor for SCWO was designed and tested to avoid plugging in the preheating section. Hot water (400–600 °C) was used as auxiliary heat source to preheat the feed to the reaction temperature. The effect of different operating parameters on the performance of the inner preheating transpiring wall reactor was investigated, and the optimized operating parameters were determined based on temperature profiles and product properties. The reaction temperature is close to 900 °C at an auxiliary heat source flow of 2.79 kg/h, and the auxiliary heat source flow is determined at 6–14 kg/h to avoid the overheating of the reactor. The useful reaction time is used to quantitatively describe the feed degradation efficiency. The outlet concentration of total organic carbon (TOC out ) and CO in the effluent gradually decreases with increasing useful reaction time. The useful reaction time needed for complete oxidation of the feed is 10.5 s for the reactor. - Highlights: • A new process to generate multiple thermal fluids by SCWO was proposed. • An inner preheating transpiring wall reactor for SCWO was designed and tested. • Hot water was used as auxiliary heat source to preheat the feed at room temperature. • Effect of operating parameters on the performance of the reactor was investigated. • The useful reaction time required for complete oxidation of the feed is 10.5 s

  3. Experimental analysis of distinct design of a batch solar water heater with integrated collector storage system

    Varghese Jaji

    2007-01-01

    Full Text Available The performance of a new design of batch solar water heater has been studied. In this system, the collector and storage were installed in one unit. Unlike the conventional design consisting of small diameter water tubes, it has a single large diameter drum which serves the dual purpose of absorber tube and storage tank. In principle it is a compound parabolic collector. The drum is sized to have a storage capacity of 100 liter to serve a family of four persons. The tests were carried out with a single glass cover and two glass covers. The tests were repeated for several days. Performance analysis of the collector has revealed that it has maximum mean daily efficiency with two glass covers as high as 37.2%. The maximum water temperature in the storage tank of 60°C has been achieved for a clear day operation at an average solar beam radiation level of 680 W/m2 and ambient temperature of 32°C. To judge the operating characteristics and to synchronize utility pattern of the collector, the different parameters such as efficiency, mean plate temperature and mass flow rate has been investigated.

  4. Bioprocess iterative batch-to-batch optimization based on hybrid parametric/nonparametric models.

    Teixeira, Ana P; Clemente, João J; Cunha, António E; Carrondo, Manuel J T; Oliveira, Rui

    2006-01-01

    This paper presents a novel method for iterative batch-to-batch dynamic optimization of bioprocesses. The relationship between process performance and control inputs is established by means of hybrid grey-box models combining parametric and nonparametric structures. The bioreactor dynamics are defined by material balance equations, whereas the cell population subsystem is represented by an adjustable mixture of nonparametric and parametric models. Thus optimizations are possible without detailed mechanistic knowledge concerning the biological system. A clustering technique is used to supervise the reliability of the nonparametric subsystem during the optimization. Whenever the nonparametric outputs are unreliable, the objective function is penalized. The technique was evaluated with three simulation case studies. The overall results suggest that the convergence to the optimal process performance may be achieved after a small number of batches. The model unreliability risk constraint along with sampling scheduling are crucial to minimize the experimental effort required to attain a given process performance. In general terms, it may be concluded that the proposed method broadens the application of the hybrid parametric/nonparametric modeling technique to "newer" processes with higher potential for optimization.

  5. Green, Eco, Innovative Design, and Manufacturing Technology of a 1-Ton per Batch Municipal Solid Waste Incinerator

    Kerdsuwan Somrat

    2016-01-01

    Full Text Available The thermal treatment of waste by incineration is considered an ultimate solution in order to get rid of waste properly by using the combustible properties of waste and transforming them into inert form and gaseous emission, with the main advantage of a huge reduction in mass and volume of treated waste, destruction of the dangerous components in waste, and obtaining green and clean energy from the exothermal reaction from the completed combustion process. In order to achieve the main goal of incineration, a good design, construction, supervision, and intensive operation and maintenance must be taken into account, especially for the small-scale incinerator. This research will deal with the green, innovative, and eco design and manufacturing technology of a 1-ton per batch municipal solid waste (MSW incinerator. The concept design of the incinerator will focus on the design of the feeding process where only one batch of waste will be discharged into the combustion chamber at one time instead of the semi-feed process, as found in the conventional incinerator. This will ease the operation of the operator and reduce the operating cost. Moreover, the innovative design includes the redesign of combustion air injection into either the primary or secondary combustion chamber in order to achieve the 3Ts of combustion (time, temperature. and turbulence. This design can eliminate the use of an auxiliary burner in the primary combustion chamber. Rethinking the innovative design of using recirculation hot flue gas for preheating of wet garbage in order to pre-dry the waste before combustion is also taken into account. The manufacturing process of the wall composition as well as other parts of the incinerator are also examined.

  6. Leaching of glass

    Hench, L.L.

    1977-01-01

    Understanding surface compositional profiles of glasses over a range of 0-2000 A with a variety of analytical instruments shows that five general types of glass surfaces exist. The surface character of a glass article depends upon bulk composition and environmental history during which surface dealkalization, film formation, and network dissolution can occur. Environmental-surface interactions generally result in complex compositional profiles of all the constituents in a glass. Durable glasses almost always develop a stable surface film which has a higher concentration of network formers than the bulk composition. Compositional effects that are used to improve glass durability usually improve the stability of the surface films. Durability tests or service conditions that lead to film destruction are especially severe for the most silicate glasses. 43 references

  7. Modelling and Simulation of the Batch Hydrolysis of Acetic ...

    The kinetic modelling of the batch synthesis of acetic acid from acetic anhydride was investigated. The kinetic data of the reaction was obtained by conducting the hydrolysis reaction in a batch reactor. A dynamic model was formulated for this process and simulation was carried out using gPROMS® an advanced process ...

  8. [Batch release of immunoglobulin and monoclonal antibody products].

    Gross, S

    2014-10-01

    The Paul-Ehrlich Institute (PEI) is an independent institution of the Federal Republic of Germany responsible for performing official experimental batch testing of sera. The institute decides about the release of each batch and performs experimental research in the field. The experimental quality control ensures the potency of the product and also the absence of harmful impurities. For release of an immunoglobulin batch the marketing authorization holder has to submit the documentation of the manufacture and the results of quality control measures together with samples of the batch to the PEI. Experimental testing is performed according to the approved specifications regarding the efficacy and safety. Since implementation of the 15th German drug law amendment, the source of antibody is not defined anymore. According to § 32 German drug law, all batches of sera need to be released by an official control laboratory. Sera are medicinal products, which contain antibodies, antibody fragments or fusion proteins with a functional antibody portion. Therefore, all batches of monoclonal antibodies and derivatives must also be released by the PEI and the marketing authorization holder has to submit a batch release application. Under certain circumstances a waiver for certain products can be issued with regard to batch release. The conditions for such a waiver apply to the majority of monoclonal antibodies.

  9. 21 CFR 80.37 - Treatment of batch pending certification.

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Treatment of batch pending certification. 80.37 Section 80.37 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL COLOR ADDITIVE CERTIFICATION Certification Procedures § 80.37 Treatment of batch pending certification...

  10. Solving a chemical batch scheduling problem by local search

    Brucker, P.; Hurink, Johann L.

    1999-01-01

    A chemical batch scheduling problem is modelled in two different ways as a discrete optimization problem. Both models are used to solve the batch scheduling problem in a two-phase tabu search procedure. The method is tested on real-world data.

  11. Dynamic Scheduling Of Batch Operations With Non-Identical Machines

    van der Zee, D.J.; van Harten, A.; Schuur, P.C.

    1997-01-01

    Batch-wise production is found in many industries. A good example of production systems which process products batch-wise are the ovens found in aircraft industry and in semiconductor manufacturing. These systems mostly consist of multiple machines of different types, given the range and volumes of

  12. Dynamic scheduling of batch operations with non-identical machines

    van der Zee, D.J.; van Harten, Aart; Schuur, Peter

    1997-01-01

    Batch-wise production is found in many industries. A good example of production systems which process products batch-wise are the ovens found in aircraft industry and in semiconductor manufacturing. These systems mostly consist of multiple machines of different types, given the range and volumes of

  13. Contribution to the investigation of induced coloured centres in sodalime glasses

    Cornu Thenard, S.

    1978-01-01

    Electron beam induced coloration of sodalime glasses naturally coloured prior to irradiation due to chromium present in the batch is studied by absorption and emission spectroscopy techniques. The influence of isochronal and isothermal heat treatments is investigated. The two possible interpretations of the observed phenomena which might seem contradictory are discussed [fr

  14. A canned food scheduling problem with batch due date

    Chung, Tsui-Ping; Liao, Ching-Jong; Smith, Milton

    2014-09-01

    This article considers a canned food scheduling problem where jobs are grouped into several batches. Jobs can be sent to the next operation only when all the jobs in the same batch have finished their processing, i.e. jobs in a batch, have a common due date. This batch due date problem is quite common in canned food factories, but there is no efficient heuristic to solve the problem. The problem can be formulated as an identical parallel machine problem with batch due date to minimize the total tardiness. Since the problem is NP hard, two heuristics are proposed to find the near-optimal solution. Computational results comparing the effectiveness and efficiency of the two proposed heuristics with an existing heuristic are reported and discussed.

  15. Spatial and interannual variability in Baltic sprat batch fecundity

    Haslob, H.; Tomkiewicz, Jonna; Hinrichsen, H.H.

    2011-01-01

    in the central Baltic Sea, namely the Bornholm Basin, Gdansk Deep and Southern Gotland Basin. Environmental parameters such as hydrography, fish condition and stock density were tested in order to investigate the observed variability in sprat fecundity. Absolute batch fecundity was found to be positively related...... to fish length and weight. Significant differences in absolute and relative batch fecundity of Baltic sprat among areas and years were detected, and could partly be explained by hydrographic features of the investigated areas. A non-linear multiple regression model taking into account fish length...... and ambient temperature explained 70% of variability in absolute batch fecundity. Oxygen content and fish condition were not related to sprat batch fecundity. Additionally, a negative effect of stock size on sprat batch fecundity in the Bornholm Basin was revealed. The obtained data and results are important...

  16. Biodenitrification in Sequencing Batch Reactors. Final report

    Silverstein, J.

    1996-01-01

    One plan for stabilization of the Solar Pond waters and sludges at Rocky Flats Plant (RFP), is evaporation and cement solidification of the salts to stabilize heavy metals and radionuclides for land disposal as low-level mixed waste. It has been reported that nitrate (NO 3- ) salts may interfere with cement stabilization of heavy metals and radionuclides. Therefore, biological nitrate removal (denitrification) may be an important pretreatment for the Solar Pond wastewaters at RFP, improving the stability of the cement final waste form, reducing the requirement for cement (or pozzolan) additives and reducing the volume of cemented low-level mixed waste requiring ultimate disposal. A laboratory investigation of the performance of the Sequencing Batch Reactor (SBR) activated sludge process developed for nitrate removal from a synthetic brine typical of the high-nitrate and high-salinity wastewaters in the Solar Ponds at Rocky Flats Plant was carried out at the Environmental Engineering labs at the University of Colorado, Boulder, between May 1, 1994 and October 1, 1995

  17. Formation And Distribution of Brittle Structures in Friction Stir Welding of AA 6061 To Copper. Influence of Preheat

    Seyed Vahid Safi

    2016-06-01

    Full Text Available In this paper, apart from introducing brand – new warm friction stir welding (WFSW method, the effect of preheating on friction stir welded of copper and aluminum alloys sheets and its influence on improving the mechanical properties of the weld were investigated. Sheets of aluminum alloy 6061 and copper with thickness of 5mm were used. The tool was made of tool steel of grade H13 with a threaded cone shape. Rotational speeds (w of 1200-1400 rpm and traverse speeds (v of 50-100 mm/min were used for better understanding the behavior of the tools during the heat input. The sheets were kept in furnace with temperature of 75 ˚C and 125˚C and welding was done afterwards. At last, tensile and micro hardness tests were done to compare the mechanical properties of the welds. Considering to the high thermal conductivity of both copper and aluminum, the reason of increase in strength of the joints could be related to the low temperature gradient between the weld zone and base metal because the heat gets out of the stir zone with lower steep. A significant increase in hardness is observed in the SZ for the following reasons: (i the presence of concentric grains with intensely refined recrystallization and (ii the presence of intermetallic compounds. The tensile test results showed 85% increase in the strength of preheated joints. The maximum strength occurs for preheating of 75˚C, rotational speed of 1200 rpm and traverse speed of 50 mm/min. In the present study, intermetallic compounds and the precipitates are moved to the grain boundaries during the welding process. These precipitates act as strong obstacles to the movements of dislocations and increase the deformation resistance of material. This phenomenon may result in locking of grain boundaries and consequently decrease of grain size. This grain refinement can improve the mechanical properties of welds. Accordingly, hardness and strength of the material will be increased.

  18. STATISTICAL EVALUATION OF SMALL SCALE MIXING DEMONSTRATION SAMPLING AND BATCH TRANSFER PERFORMANCE - 12093

    GREER DA; THIEN MG

    2012-01-12

    The ability to effectively mix, sample, certify, and deliver consistent batches of High Level Waste (HLW) feed from the Hanford Double Shell Tanks (DST) to the Waste Treatment and Immobilization Plant (WTP) presents a significant mission risk with potential to impact mission length and the quantity of HLW glass produced. DOE's Tank Operations Contractor, Washington River Protection Solutions (WRPS) has previously presented the results of mixing performance in two different sizes of small scale DSTs to support scale up estimates of full scale DST mixing performance. Currently, sufficient sampling of DSTs is one of the largest programmatic risks that could prevent timely delivery of high level waste to the WTP. WRPS has performed small scale mixing and sampling demonstrations to study the ability to sufficiently sample the tanks. The statistical evaluation of the demonstration results which lead to the conclusion that the two scales of small DST are behaving similarly and that full scale performance is predictable will be presented. This work is essential to reduce the risk of requiring a new dedicated feed sampling facility and will guide future optimization work to ensure the waste feed delivery mission will be accomplished successfully. This paper will focus on the analytical data collected from mixing, sampling, and batch transfer testing from the small scale mixing demonstration tanks and how those data are being interpreted to begin to understand the relationship between samples taken prior to transfer and samples from the subsequent batches transferred. An overview of the types of data collected and examples of typical raw data will be provided. The paper will then discuss the processing and manipulation of the data which is necessary to begin evaluating sampling and batch transfer performance. This discussion will also include the evaluation of the analytical measurement capability with regard to the simulant material used in the demonstration tests. The

  19. Small Scale Mixing Demonstration Batch Transfer and Sampling Performance of Simulated HLW - 12307

    Jensen, Jesse; Townson, Paul; Vanatta, Matt [EnergySolutions, Engineering and Technology Group, Richland, WA, 99354 (United States)

    2012-07-01

    The ability to effectively mix, sample, certify, and deliver consistent batches of High Level Waste (HLW) feed from the Hanford Double Shell Tanks (DST) to the Waste treatment Plant (WTP) has been recognized as a significant mission risk with potential to impact mission length and the quantity of HLW glass produced. At the end of 2009 DOE's Tank Operations Contractor, Washington River Protection Solutions (WRPS), awarded a contract to EnergySolutions to design, fabricate and operate a demonstration platform called the Small Scale Mixing Demonstration (SSMD) to establish pre-transfer sampling capacity, and batch transfer performance data at two different scales. This data will be used to examine the baseline capacity for a tank mixed via rotational jet mixers to transfer consistent or bounding batches, and provide scale up information to predict full scale operational performance. This information will then in turn be used to define the baseline capacity of such a system to transfer and sample batches sent to WTP. The Small Scale Mixing Demonstration (SSMD) platform consists of 43'' and 120'' diameter clear acrylic test vessels, each equipped with two scaled jet mixer pump assemblies, and all supporting vessels, controls, services, and simulant make up facilities. All tank internals have been modeled including the air lift circulators (ALCs), the steam heating coil, and the radius between the wall and floor. The test vessels are set up to simulate the transfer of HLW out of a mixed tank, and collect a pre-transfer sample in a manner similar to the proposed baseline configuration. The collected material is submitted to an NQA-1 laboratory for chemical analysis. Previous work has been done to assess tank mixing performance at both scales. This work involved a combination of unique instruments to understand the three dimensional distribution of solids using a combination of Coriolis meter measurements, in situ chord length distribution

  20. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    The Aspergillus niger strain BO-1 was grown in batch, continuous (chemostat) and fed-batch cultivations in order to study the production of the extracellular enzyme glucoamylase under different growth conditions. In the pH range 2.5-6.0, the specific glucoamylase productivity and the specific...

  1. Batch-to-batch quality consistency evaluation of botanical drug products using multivariate statistical analysis of the chromatographic fingerprint.

    Xiong, Haoshu; Yu, Lawrence X; Qu, Haibin

    2013-06-01

    Botanical drug products have batch-to-batch quality variability due to botanical raw materials and the current manufacturing process. The rational evaluation and control of product quality consistency are essential to ensure the efficacy and safety. Chromatographic fingerprinting is an important and widely used tool to characterize the chemical composition of botanical drug products. Multivariate statistical analysis has showed its efficacy and applicability in the quality evaluation of many kinds of industrial products. In this paper, the combined use of multivariate statistical analysis and chromatographic fingerprinting is presented here to evaluate batch-to-batch quality consistency of botanical drug products. A typical botanical drug product in China, Shenmai injection, was selected as the example to demonstrate the feasibility of this approach. The high-performance liquid chromatographic fingerprint data of historical batches were collected from a traditional Chinese medicine manufacturing factory. Characteristic peaks were weighted by their variability among production batches. A principal component analysis model was established after outliers were modified or removed. Multivariate (Hotelling T(2) and DModX) control charts were finally successfully applied to evaluate the quality consistency. The results suggest useful applications for a combination of multivariate statistical analysis with chromatographic fingerprinting in batch-to-batch quality consistency evaluation for the manufacture of botanical drug products.

  2. Batch-To-Batch Rational Feedforward Control : From Iterative Learning to Identification Approaches, with Application to a Wafer Stage

    Blanken, L.; Boeren, F.A.J.; Bruijnen, D.J.H.; Oomen, T.A.E.

    2017-01-01

    Feedforward control enables high performance for industrial motion systems that perform nonrepeating motion tasks. Recently, learning techniques have been proposed that improve both performance and flexibility to nonrepeating tasks in a batch-To-batch fashion by using a rational parameterization in

  3. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Gupta Rishi

    2012-03-01

    Full Text Available Abstract Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates.

  4. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    2012-01-01

    Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v) and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates. PMID:22433563

  5. Composition and property measurements for PHA Phase 4 glasses

    Edwards, T.B.

    2000-01-01

    The results presented in this report are for nine Precipitate Hydrolysis Aqueous (PHA) Phase 4 glasses. Three of the glasses contained HM sludge at 22, 26, and 30 wt% respectively, 10 wt% PHA and 1.25 wt% monosodium titanate (MST), all on an oxide basis. The remaining six glasses were selected from the Phase 1 and Phase 2 studies (Purex sludge) but with an increased amount of MST. The high-end target for MST of 2.5 wt% oxide was missed in Phases 1 and 2 due to ∼30 wt% water content of the MST. A goal of this Phase 4 study was to determine whether this increase in titanium concentration from the MST had any impact on glass quality or processibility. Two of the glasses, pha14c and pha15c, were rebatched and melted due to apparent batching errors with pha14 and pha15. The models currently in the Defense Waste Processing Facility's (DWPF) Product Composition Control System (PCCS) were used to predict durability, homogeneity, liquidus, and viscosity for these nine glasses. All of the HM glasses and half of the Purex glasses were predicted to be phase separated, and consequently prediction of glass durability is precluded with the cument models for those glasses that failed the homogeneity constraint. If one may ignore the homogeneity constraint, the measured durabilities were within the 95% prediction limits of the model. Further efforts will be required to resolve this issue on phase separation (inhomogeneity). The liquidus model predicted unacceptable liquidus temperatures for four of the nine glasses. The approximate, bounding liquidus temperatures measured for all had upper limits of 1,000 C or less. Given the fact that liquidus temperatures were only approximated, the 30 wt% loading of Purex may be near or at the edge of acceptability for liquidus. The measured viscosities were close to the predictions of the model. For the Purex glasses, pha12c and pha15c, the measured viscosities of 28 and 23 poise, respectively, indicate that DWPF processing may be compromised

  6. NEPHELINE FORMATION STUDY FOR SLUDGE BATCH 4: PHASE 3 EXPERIMENTAL RESULTS

    Fox, K

    2006-01-01

    This Phase 3 study was undertaken to complement the previous phases of the nepheline formation studies1, 2 by continuing the investigation into the ability of the nepheline discriminator to predict the occurrence of nepheline crystallization in Sludge Batch 4 (SB4) glasses and into the impact of such phases on the durability of the SB4 glasses. The Phase 3 study had two primary objectives. The first was to continue to demonstrate the ability of the discriminator value to adequately predict the nepheline formation potential for specific glass systems of interest. The second was to generate additional data that have a high probability of supporting the SB4 variability study. To support these two objectives, sixteen glasses were selected based on the most recent SB4 compositional projection, Case 15C Blend 1.3 Four different frits were included, based on previous assessments of projected operating windows and melt rate,4, 5 with four WLs selected for each frit. Eight of these frit-sludge combinations covered WLs which tightly bound the nepheline discriminator value of 0.62, with the intent of refining this value to a level of confidence where it can be incorporated into offline administrative controls and/or the Process Composition Control System (PCCS) to support Slurry Mix Evaporator (SME) acceptability decisions. The remaining eight frit-sludge combinations targeted lower WLs (35 and 40%) and were prepared and analyzed to contribute needed data to the ComPro database6 to support a potential variability study for SB4

  7. Fractography of glass

    Tressler, Richard

    1994-01-01

    As the first major reference on glass fractography, contributors to this volume offer a comprehensive account of the fracture of glass as well as various fracture surface topography Contributors discuss optical fibers, glass containers, and flatglass fractography In addition, papers explore fracture origins; the growth of the original flaws of defects; and macroscopic fracture patterns from which fracture patterns evolve This volume is complete with photographs and schematics

  8. Diamond turning of glass

    Blackley, W.S.; Scattergood, R.O.

    1988-12-01

    A new research initiative will be undertaken to investigate the critical cutting depth concepts for single point diamond turning of brittle, amorphous materials. Inorganic glasses and a brittle, thermoset polymer (organic glass) are the principal candidate materials. Interrupted cutting tests similar to those done in earlier research are Ge and Si crystals will be made to obtain critical depth values as a function of machining parameters. The results will provide systematic data with which to assess machining performance on glasses and amorphous materials

  9. Glass to contain wastes

    Moncouyoux, M.; Jacquet-Francillon, M.

    1994-01-01

    Here are the tables and figures presented during the conference on the glass to confine high level radioactive wastes: definition, fabrication, storage and disposal. The composition of glasses are detailed, their properties and the vitrification proceeding. The behaviour of these glasses in front of water, irradiation and heat are shown. The characteristics of parcels are given according to the radiation protection rule, ALARA principle, the concept of multi-barriers and the geological stability

  10. Glass microspheres for brachytherapy

    Prado, Miguel O.; Prastalo, Simon; Blaumann, Herman; Longhino, Juan M.; Repetto Llamazares, A.H.V.

    2007-01-01

    We developed the capacity to produce glass microspheres containing in their structure one or more radioactive isotopes useful for brachytherapy. We studied the various facts related with their production: (Rare earth) alumino silicate glass making, glass characterization, microspheres production, nuclear activation through (n,γ) nuclear reactions, mechanical characterization before and after irradiation. Corrosion tests in simulated human plasma and mechanical properties characterization were done before and after irradiation. (author) [es

  11. Dosimetric Characteristics of Radio-Photoluminescent Glass Dosimeters for Medical Applications: Linearity

    Shehzadi, N. N.; Jeong, J. P.; Kim, B. C.; Kim, I. J.; Yi, C. Y. [Center for Ionizing Radiation, Korea Research Institute of Standards and Science, Seoul (Korea, Republic of)

    2017-04-15

    Radio-photoluminescent glass dosimeter (GD) has advantage of non-destructive reading process, negligible fading and superior radiation detection characteristics than other personal dosimeters like thermoluminescent dosimeters (TLD) or film dosimeters. In this study, one dosimetric characteristic of GDs, dose linearity was evaluated with two different approaches: one for each set of GDs selected and another for a batch of them using accumulated doses of same set of GDs and GDs in a batch, respectively. Within a dose range upto 10 Gy, not only each set of GDs but also a batch of them showed excellent linearity. Within a dose range upto 10 Gy, not only each set of GDs but also a batch of them showed excellent linearity.

  12. DWPF coupled feed flowsheet material balance with batch one sludge and copper nitrate catalyst

    Choi, A.S.

    1993-09-28

    The SRTC has formally transmitted a recommendation to DWPF to replace copper formate with copper nitrate as the catalyst form during precipitate hydrolysis [1]. The SRTC was subsequently requested to formally document the technical bases for the recommendation. A memorandum was issued on August 23, 1993 detailing the activities (and responsible individuals) necessary to address the impact of this change in catalyst form on process compatibility, safety, processibility environmental impact and product glass quality [2]. One of the activities identified was the preparation of a material balance in which copper nitrate is substituted for copper formate and the identification of key comparisons between this material balance and the current Batch 1 sludge -- Late Wash material balance [3].

  13. A study on pre-heat conditions in equivalent-dose estimation of holocene loess using single-aliquot regenerative-dose (SAR) protocol

    Jia Yaofeng; Huang Chunchang; Pang Jiangli; Lu Xinwei; Zhang Xu

    2007-01-01

    Through various arrangements of pre-heat and cut-heat temperatures in the equivalent-dose estimation of Holocene loess using a Double-SAR dating protocol, the paper estimated the equivalent-doses from several loess samples by application of IRSL and Post-IR OSL signals, respectively. The measured results present that the equivalent-dose depends on the heat temperature, especially depends on the cut-heat temperature, showing the equivalent-dose increases with the cut-heat temperature; a plateau of equivalent-dose appears at the 200-300 degree C preheat temperatures and the 200-240 degree C cut-heat temperatures, furthermore, the equivalent-doses estimated by IRSL and Post-IR OSL signals respectively are close to each other, which resulted from the similar sensitivity change directions of optical stimulated signals and their smaller change ranges in the measurement cycles using the various temperatures of pre-heat and cut-heat. This suggests that the 200-300 degree C pre-heat temperatures and the 200-240 degree C cut-heat temperatures are fit for dating young Holocene loess samples. (authors)

  14. The Effect of Air Preheat at Atmospheric Pressure on the Formation of NO(x) in the Quick-Mix Sections of an Axially Staged Combustor

    Vardakas, M. A.; Leong, M. Y.; Brouwer, J.; Samuelsen, G. S.; Holdeman, J. D.

    1999-01-01

    The Rich-burn/Quick-mix/Lean-burn (RQL) combustor concept has been proposed to minimize the formation of nitrogen oxides (NO(x)) in gas turbine systems. The success of this combustor strategy is dependent upon the efficiency of the mixing section bridging the fuel-rich and fuel-lean stages. Note that although these results were obtained from an experiment designed to study an RQL mixer, the link between mixing and NOx signatures is considerably broader than this application, in that the need to understand this link exists in most advanced combustors. The experiment reported herein was designed to study the effects of inlet air temperature on NO(x) formation in a mixing section. The results indicate that NO(x) emission is increased for all preheated cases compared to non-preheated cases. When comparing the various mixing modules, the affect of jet penetration is important, as this determines where NO(x) concentrations peak, and affects overall NO(x) production. Although jet air comprises 70 percent of the total airflow, the impact that jet air preheat has on overall NO(x) emissions is small compared to preheating both main and jet air flow.

  15. A computer simulation of the transient response of a 4 cylinder Stirling engine with burner and air preheater in a vehicle

    Martini, W. R.

    1981-01-01

    A series of computer programs are presented with full documentation which simulate the transient behavior of a modern 4 cylinder Siemens arrangement Stirling engine with burner and air preheater. Cold start, cranking, idling, acceleration through 3 gear changes and steady speed operation are simulated. Sample results and complete operating instructions are given. A full source code listing of all programs are included.

  16. Effects of preheating of crude palm oil (CPO) on injection system, performance and emission of a diesel engine

    Bari, S.; Lim, T.H.; Yu, C.W.

    2002-01-01

    Crude palm oil (CPO) is one of the vegetable oils that have potential for use as fuels for diesel engines. CPO is renewable, and is safe and easy to handle. However, at room temperature (30-32 deg C) CPO has a viscosity about 10 times higher than that of diesel. To lower CPO's viscosity to the level of diesel's viscosity, a heating temperature of at least 92 deg C is needed. At this temperature, there is a concern that the close-fitting parts of the injection system might be affected. This study focused on finding out the effects of preheating of fuel on the injection system utilising a modified method of friction test, which involves injecting fuel outside the combustion chamber during motoring. Results show that preheating of CPO lowered CPO's viscosity and provided smooth fuel flow, but did not affect the injection system, even heating up to 100 deg C. Nevertheless, heating up to such a high temperature offered no benefits in terms of engine performance. However, heating is necessary for smooth flow and to avoid fuel filter clogging. Both can be achieved by heating CPO to 60 deg C. Combustion analyses comparisons between CPO and diesel found that CPO produced a higher peak pressure of 6%, a shorter ignition delay of 2.6 deg, a lower maximum heat release rate and a longer combustion period. Over the entire load range, CPO combustion produced average CO and NO emissions that were 9.2 and 29.3% higher, respectively, compared with those from diesel combustion. (Author)

  17. Silicate glasses. Chapter 1

    Lutze, W.

    1988-01-01

    This chapter is a survey of world-wide research and development efforts in nuclear waste glasses and its production technology. The principal glasses considered are silicate glasses which contain boron, i.e. borosilicate glass. A historical overview of waste form development programs in nine countries is followed by a summary of the design criteria for borosilicate glass compositions glass compositions. In the sections on glass properties the waste form is characterized in terms of potential alterations under the influence of heat, thermal gradients, radiation, aqueous solutions and combinations thereof. The topics are phase transformations, mechanical properties, radiation effects and chemical durability. The results from studies of volcanic glasses, as natural analogues for borosilicate nuclear waste glasses in order to verify predictions obtained from short-term tests in the laboratory, have been compiled in a special section on natural analogues. A special section on advanced vitrification techniques summarizes the various actual and potential processing schemes and describes the facilities. The literature has been considered until 1985. (author). 430 refs.; 68 figs.; 29 tabs

  18. Glass and vitrification

    Barton, J.L.; Vacher, R.; Moncouyoux, J.P.; Vernaz, E.

    1997-01-01

    Most glasses used as materials are oxides glasses that are produced by a quick quench of a liquid. Glasses are characterized by the absence of periodicity in the atomic arrangements, they do not have symmetries and do not present order over a long distance. This series of 4 short articles present: 1) the properties of glass and its industrial story, 2) the glass structure, 3) a forty years long story of glass as dies used to confine wastes and 4) the methodology used to study the behaviour of glass over very long periods of time. This methodology is based on 5 steps: 1) define and specify the material to study (the prediction of long term alteration of a material is nonsense unless you know well its initial properties), 2) identify all the alteration processes that are likely to happen, determine their kinetics and the influence of environmental parameters, 3) develop mathematical models in order to simulate long-term behaviour of glasses, 4) determine the release rates of the radionuclides confined in the glass, and 5) validate data and models, it is not possible to expect a complete validation of a model that will be extrapolated over tens of thousands of years, nevertheless some ways of validation can lead to a satisfactory level of confidence taking into account reasonable uncertainties. (A.C.)

  19. Demonstration of the Defense Waste Processing Facility vitrification process for Tank 42 radioactive sludge -- Glass preparation and characterization

    Bibler, N.E.; Fellinger, T.L.; Marshall, K.M.; Crawford, C.L.; Cozzi, A.D.; Edwards, T.B.

    1999-01-01

    The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) is currently processing and immobilizing the radioactive high level waste sludge at SRS into a durable borosilicate glass for final geological disposal. The DWPF has recently finished processing the first radioactive sludge batch, and is ready for the second batch of radioactive sludge. The second batch is primarily sludge from Tank 42. Before processing this batch in the DWPF, the DWPF process flowsheet has to be demonstrated with a sample of Tank 42 sludge to ensure that an acceptable melter feed and glass can be made. This demonstration was recently completed in the Shielded Cells Facility at SRS. An earlier paper in these proceedings described the sludge composition and processes necessary for producing an acceptable melter fee. This paper describes the preparation and characterization of the glass from that demonstration. Results substantiate that Tank 42 sludge after mixing with the proper amount of glass forming frit (Frit 200) can be processed to make an acceptable glass

  20. Evaluation of Glass Density to Support the Estimation of Fissile Mass Loadings from Iron Concentrations in SB6 Glasses

    Edwards, T.; Peeler, D.

    2010-12-15

    The Department of Energy - Savannah River (DOE-SR) previously provided direction to Savannah River Remediation (SRR) to maintain fissile concentration in glass below 897 g/m{sup 3}. In support of the guidance, the Savannah River National Laboratory (SRNL) provided a technical basis and a supporting Microsoft{reg_sign} Excel{reg_sign} spreadsheet for the evaluation of fissile loading in Sludge Batch 5 glass based on the Fe concentration in glass as determined by the measurements from the Slurry Mix Evaporator (SME) acceptability analysis. SRR has since requested that SRNL provide the necessary information to allow SRR to update the Excel spreadsheet so that it may be used to maintain fissile concentration in glass below 897 g/m{sup 3} during the processing of Sludge Batch 6 (SB6). One of the primary inputs into the fissile loading spreadsheet includes a bounding density for SB6-based glasses. Based on the measured density data of select SB6 variability study glasses, SRNL recommends that SRR utilize the 99/99 Upper Tolerance Limit (UTL) density value at 38% WL (2.823 g/cm{sup 3}) as a bounding density for SB6 glasses to assess the fissile concentration in this glass system. That is, the 2.823 g/cm{sup 3} is recommended as a key (and fixed) input into the fissile concentration spreadsheet for SB6 processing. It should be noted that no changes are needed to the underlying structure of the Excel based spreadsheet to support fissile assessments for SB6. However, SRR should update the other key inputs to the spreadsheet that are based on fissile and Fe concentrations reported from the SB6 Waste Acceptance Product Specification (WAPS) sample. The purpose of this technical report is to present the density measurements that were determined for the SB6 variability study glasses and to conduct a statistical evaluation of these measurements to provide a bounding density value that may be used as input to the Excel{reg_sign} spreadsheet to be employed by SRR to maintain the

  1. Elimination of water pathogens with solar radiation using an automated sequential batch CPC reactor.

    Polo-López, M I; Fernández-Ibáñez, P; Ubomba-Jaswa, E; Navntoft, C; García-Fernández, I; Dunlop, P S M; Schmid, M; Byrne, J A; McGuigan, K G

    2011-11-30

    Solar disinfection (SODIS) of water is a well-known, effective treatment process which is practiced at household level in many developing countries. However, this process is limited by the small volume treated and there is no indication of treatment efficacy for the user. Low cost glass tube reactors, together with compound parabolic collector (CPC) technology, have been shown to significantly increase the efficiency of solar disinfection. However, these reactors still require user input to control each batch SODIS process and there is no feedback that the process is complete. Automatic operation of the batch SODIS process, controlled by UVA-radiation sensors, can provide information on the status of the process, can ensure the required UVA dose to achieve complete disinfection is received and reduces user work-load through automatic sequential batch processing. In this work, an enhanced CPC photo-reactor with a concentration factor of 1.89 was developed. The apparatus was automated to achieve exposure to a pre-determined UVA dose. Treated water was automatically dispensed into a reservoir tank. The reactor was tested using Escherichia coli as a model pathogen in natural well water. A 6-log inactivation of E. coli was achieved following exposure to the minimum uninterrupted lethal UVA dose. The enhanced reactor decreased the exposure time required to achieve the lethal UVA dose, in comparison to a CPC system with a concentration factor of 1.0. Doubling the lethal UVA dose prevented the need for a period of post-exposure dark inactivation and reduced the overall treatment time. Using this reactor, SODIS can be automatically carried out at an affordable cost, with reduced exposure time and minimal user input. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Elimination of water pathogens with solar radiation using an automated sequential batch CPC reactor

    Polo-López, M.I.; Fernández-Ibáñez, P.; Ubomba-Jaswa, E.; Navntoft, C.; García-Fernández, I.; Dunlop, P.S.M.; Schmid, M.; Byrne, J.A.

    2011-01-01

    Solar disinfection (SODIS) of water is a well-known, effective treatment process which is practiced at household level in many developing countries. However, this process is limited by the small volume treated and there is no indication of treatment efficacy for the user. Low cost glass tube reactors, together with compound parabolic collector (CPC) technology, have been shown to significantly increase the efficiency of solar disinfection. However, these reactors still require user input to control each batch SODIS process and there is no feedback that the process is complete. Automatic operation of the batch SODIS process, controlled by UVA-radiation sensors, can provide information on the status of the process, can ensure the required UVA dose to achieve complete disinfection is received and reduces user work-load through automatic sequential batch processing. In this work, an enhanced CPC photo-reactor with a concentration factor of 1.89 was developed. The apparatus was automated to achieve exposure to a pre-determined UVA dose. Treated water was automatically dispensed into a reservoir tank. The reactor was tested using Escherichia coli as a model pathogen in natural well water. A 6-log inactivation of E. coli was achieved following exposure to the minimum uninterrupted lethal UVA dose. The enhanced reactor decreased the exposure time required to achieve the lethal UVA dose, in comparison to a CPC system with a concentration factor of 1.0. Doubling the lethal UVA dose prevented the need for a period of post-exposure dark inactivation and reduced the overall treatment time. Using this reactor, SODIS can be automatically carried out at an affordable cost, with reduced exposure time and minimal user input.

  3. Elimination of water pathogens with solar radiation using an automated sequential batch CPC reactor

    Polo-Lopez, M.I., E-mail: mpolo@psa.es [Plataforma Solar de Almeria - CIEMAT, PO Box 22, 04200 Tabernas, Almeria (Spain); Fernandez-Ibanez, P., E-mail: pilar.fernandez@psa.es [Plataforma Solar de Almeria - CIEMAT, PO Box 22, 04200 Tabernas, Almeria (Spain); Ubomba-Jaswa, E., E-mail: euniceubombajaswa@yahoo.com [Natural Resources and the Environment, CSIR, PO Box 395, Pretoria (South Africa); Navntoft, C., E-mail: christian.navntoft@solarmate.com.ar [Instituto de Investigacion e Ingenieria Ambiental, Universidad Nacional de San Martin (3iA-UNSAM), Peatonal Belgrano 3563, B1650ANQ San Martin (Argentina); Universidad Tecnologica Nacional - Facultad Regional Buenos Aires - Departamento de Ingenieria Civil - Laboratorio de Estudios sobre Energia Solar, (UTN-FRBA-LESES), Mozart 2300, (1407) Ciudad Autonoma de Buenos Aires, Republica Argentina (Argentina); Garcia-Fernandez, I., E-mail: irene.garcia@psa.es [Plataforma Solar de Almeria - CIEMAT, PO Box 22, 04200 Tabernas, Almeria (Spain); Dunlop, P.S.M., E-mail: psm.dunlop@ulster.ac.uk [Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2 (Ireland); Schmid, M. [Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2 (Ireland); Byrne, J.A., E-mail: j.byrne@ulster.ac.uk [Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin 2 (Ireland); and others

    2011-11-30

    Solar disinfection (SODIS) of water is a well-known, effective treatment process which is practiced at household level in many developing countries. However, this process is limited by the small volume treated and there is no indication of treatment efficacy for the user. Low cost glass tube reactors, together with compound parabolic collector (CPC) technology, have been shown to significantly increase the efficiency of solar disinfection. However, these reactors still require user input to control each batch SODIS process and there is no feedback that the process is complete. Automatic operation of the batch SODIS process, controlled by UVA-radiation sensors, can provide information on the status of the process, can ensure the required UVA dose to achieve complete disinfection is received and reduces user work-load through automatic sequential batch processing. In this work, an enhanced CPC photo-reactor with a concentration factor of 1.89 was developed. The apparatus was automated to achieve exposure to a pre-determined UVA dose. Treated water was automatically dispensed into a reservoir tank. The reactor was tested using Escherichia coli as a model pathogen in natural well water. A 6-log inactivation of E. coli was achieved following exposure to the minimum uninterrupted lethal UVA dose. The enhanced reactor decreased the exposure time required to achieve the lethal UVA dose, in comparison to a CPC system with a concentration factor of 1.0. Doubling the lethal UVA dose prevented the need for a period of post-exposure dark inactivation and reduced the overall treatment time. Using this reactor, SODIS can be automatically carried out at an affordable cost, with reduced exposure time and minimal user input.

  4. Characterization of glass and glass ceramic nuclear waste forms

    Lutze, W.; Borchardt, J.; De, A.K.

    1979-01-01

    Characteristics of solidified nuclear waste forms, glass and glass ceramic compositions and the properties (composition, thermal stability, crystallization, phase behavior, chemical stability, mechanical stability, and radiation effects) of glasses and glass ceramics are discussed. The preparation of glass ceramics may be an optional step for proposed vitrification plants if tailored glasses are used. Glass ceramics exhibit some improved properties with respect to glasses. The overall leach resistance is similar to that of glasses. An increased leach resistance may become effective for single radionuclides being hosted in highly insoluble crystal phases mainly when higher melting temperatures are applicable in order to get more leach resistant residual glass phases. The development of glass ceramic is going on. The technological feasibility is still to be demonstrated. The potential gain of stability when using glass ceramics qualifies the material as an alternative nuclear waste form

  5. Low cost batch fabrication of microdevices using ultraviolet light-emitting diode photolithography technique

    Lee, Neam Heng; Swamy, Varghese; Ramakrishnan, Narayanan

    2016-01-01

    Solid-state technology has enabled the use of light-emitting diodes (LEDs) in lithography systems due to their low cost, low power requirement, and higher efficiency relative to the traditional mercury lamp. Uniform irradiance distribution is essential for photolithography to ensure the critical dimension (CD) of the feature fabricated. However, light illuminated from arrays of LEDs can have nonuniform irradiance distribution, which can be a problem when using LED arrays as a source to batch-fabricate multiple devices on a large wafer piece. In this study, the irradiance distribution of an UV LED array was analyzed, and the separation distance between light source and mask optimized to obtain maximum irradiance uniformity without the use of a complex lens. Further, employing a diffuser glass enhanced the fabrication process and the CD loss was minimized to an average of 300 nm. To assess the performance of the proposed technology, batch fabrication of surface acoustic wave devices on lithium niobate substrate was carried out, and all the devices exhibited identical insertion loss of -18 dB at a resonance frequency of 39.33 MHz. The proposed low-cost UV lithography setup can be adapted in academic laboratories for research and teaching on microdevices.

  6. Production of Polystyrene Open-celled Microcellular Foam in Batch Process by Super Critical CO2

    M.S. Enayati

    2010-12-01

    Full Text Available Open-celled foams are capable to allow the passage of fluids through their structure, because of interconnections between the open cells or bubbles and therefore these structures can be used as a membrane and filter. In thiswork, we have studied the production of polystyrene open-celled microcellular foam by using CO2 as blowing agent. To achieve such structures, it is necessary to control the stages of growth in such a way that the cells would connect to each other through the pores without any coalescence. The required processing condition to achieve open-celled structures is predictable by a model theory of opened-cell. This model suggests that at least a 130 bar saturation pressure and foaming time between 9 and 58 s are required for this system. The temperature range has been selected for to be both higher than polymer glass transition temperature and facilitating the foaming process. Experimental results in the batch foaming process has verified the model quite well. The SEM and mercury porousimetry tests show the presence of pores between the cells with open-celled structure. Experimental results show that by increasing the saturation pressure and the foaming temperature, there is a drop in the time required for open-celled structure formation. A 130 bar saturation pressure, 150o C foaming temperature and 60 s foaming time, suggest the attainment of open-celled microcellular foam based on polystyrene/CO2 system in the batch process.

  7. Relaxations in spin glasses: Similarities and differences from ordinary glasses

    Ngai, K.L.; Rajagopal, A.K.; Huang, C.Y.

    1984-01-01

    Relaxation phenomena have become a major concern in the physics of spin glasses. There are certain resemblances of these relaxation properties to those of ordinary glasses. In this work, we compare the relaxation properties of spin glasses near the freezing temperature with those of glasses near the glass transition temperature. There are similarities between the two types of glasses. Moreover, the relaxation properties of many glasses and spin glasses are in conformity with two coupled ''universality'' relations predicted by a recent model of relaxations in condensed matter

  8. Batch-to-batch uniformity of bacterial community succession and flavor formation in the fermentation of Zhenjiang aromatic vinegar.

    Wang, Zong-Min; Lu, Zhen-Ming; Yu, Yong-Jian; Li, Guo-Quan; Shi, Jin-Song; Xu, Zheng-Hong

    2015-09-01

    Solid-state fermentation of traditional Chinese vinegar is a mixed-culture refreshment process that proceeds for many centuries without spoilage. Here, we investigated bacterial community succession and flavor formation in three batches of Zhenjiang aromatic vinegar using pyrosequencing and metabolomics approaches. Temporal patterns of bacterial succession in the Pei (solid-state vinegar culture) showed no significant difference (P > 0.05) among three batches of fermentation. In all the batches investigated, the average number of community operational taxonomic units (OTUs) decreased dramatically from 119 ± 11 on day 1 to 48 ± 16 on day 3, and then maintained in the range of 61 ± 9 from day 5 to the end of fermentation. We confirmed that, within a batch of fermentation process, the patterns of bacterial diversity between the starter (took from the last batch of vinegar culture on day 7) and the Pei on day 7 were similar (90%). The relative abundance dynamics of two dominant members, Lactobacillus and Acetobacter, showed high correlation (coefficient as 0.90 and 0.98 respectively) among different batches. Furthermore, statistical analysis revealed dynamics of 16 main flavor metabolites were stable among different batches. The findings validate the batch-to-batch uniformity of bacterial community succession and flavor formation accounts for the quality of Zhenjiang aromatic vinegar. Based on our understanding, this is the first study helps to explain the rationality of age-old artistry from a scientific perspective. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Evaluation of Structural Cellular Glass

    Adams, M. A.; Zwissler, J. G.

    1984-01-01

    Preliminary design information presented. First report discusses state of structural-cellular-glass programs as of June 1979. Second report gives further details of program to develop improved cellular glasses and to characterize properties of glasses and commercially available materials.

  10. Electric glass capturing markets

    Wikman, K.; Wikstroem, T.

    1996-11-01

    Electric glass has found its place on the construction market. In public buildings, electrically heatable windows are becoming the leading option for large glass walls. Studies on detached houses, both new and renovated, show that floor heating combined with electrically heatable windowpanes is the best choice with respect to resident`s comfort. (orig.)

  11. Radioresistance of inorganic glasses

    Vorob'ev, A.A.; Zavadovskaya, E.K.; Fedorov, B.V.; Starodubtsev, V.A.

    1977-01-01

    Regularities are considered in the variation of properties of glass due to irradiations. On the basis of previous theoretical statements and experimental investigations, it is inferred that the irradiation resistance of glasses of the same type, synthesis conditions, content of impurities and amount of imperfections, is a function of the ''element-oxygen'' bond energy. The irradiation resistance depends on the number and the nature of glass structure imperfections. The averaged level of bonding forces is indicative of the glass formation temperature; the imperfections in glasses are formed in structure elements whose amount predominates as compared to the others. Electric charges which accumulate on the crack surface tend to increase its size, thus lessening even further the electric strength of the dielectric. The greater the irradiation time, the greater the number of irradiation imperfections causing a drop in the electric strength of glass. When choosing a glass for service in a radiation field, it is necessary to select those of a highest temperature of glass formation and with a least amount of imperfections

  12. Nucleation in ZBLAN glasses

    de Leede, G.L.A.; Waal, de H.

    1989-01-01

    Nucleation rates were detd. in a ZrF4-BaF2-NaF-LaF3-AlF3 glass (ZBLAN) using an optical method. The results were compared with a similar glass having a slightly different compn. The difference in the nucleation rate is explained by classical nucleation theory using calcd. free-energy differences

  13. SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 6 QUALIFICATION

    Pareizs, J.; Pickenheim, B.; Bannochie, C.; Billings, A.; Bibler, N.; Click, D.

    2010-10-01

    Prior to initiating a new sludge batch in the Defense Waste Processing Facility (DWPF), Savannah River National Laboratory (SRNL) is required to simulate this processing, including Chemical Process Cell (CPC) simulation, waste glass fabrication, and chemical durability testing. This report documents this simulation for the next sludge batch, Sludge Batch 6 (SB6). SB6 consists of Tank 12 material that has been transferred to Tank 51 and subjected to Low Temperature Aluminum Dissolution (LTAD), Tank 4 sludge, and H-Canyon Pu solutions. Following LTAD and the Tank 4 addition, Liquid Waste Operations (LWO) provided SRNL a 3 L sample of Tank 51 sludge for SB6 qualification. Pu solution from H Canyon was also received. SB6 qualification included washing the sample per LWO plans/projections (including the addition of Pu from H Canyon), DWPF CPC simulations, waste glass fabrication (vitrification), and waste glass characterization and chemical durability evaluation. The following are significant observations from this demonstration. Sludge settling improved slightly as the sludge was washed. SRNL recommended (and the Tank Farm implemented) one less wash based on evaluations of Tank 40 heel projections and projections of the glass composition following transfer of Tank 51 to Tank 40. Thorium was detected in significant quantities (>0.1 wt % of total solids) in the sludge. In past sludge batches, thorium has been determined by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS), seen in small quantities, and reported with the radionuclides. As a result of the high thorium, SRNL-AD has added thorium to their suite of Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) elements. The acid stoichiometry for the DWPF Sludge Receipt and Adjustment Tank (SRAT) processing of 115%, or 1.3 mol acid per liter of SRAT receipt slurry, was adequate to accomplish some of the goals of SRAT processing: nitrite was destroyed to below 1,000 mg/kg and mercury was removed to

  14. DEFENSE WASTE PROCESSING FACILITY ANALYTICAL METHOD VERIFICATION FOR THE SLUDGE BATCH 5 QUALIFICATION SAMPLE

    Click, D; Tommy Edwards, T; Henry Ajo, H

    2008-01-01

    sample by SRNL which consists of the final composition of the sludge (the SB5 Blend); (2) Given the heel of SB4 in Tank 40, the DWPF lab should monitor the aluminum concentration in the first 10 SRAT Receipt batches of SB5 using both CC and sodium peroxide/hydroxide fusion to evaluate the adequacy of aluminum recovery by the CC method for this sludge batch; and (3) SRNL and the DWPF lab should investigate if comparisons between the elemental concentrations of the SME product glass (adjusted for frit addition) obtained by the mixed acid and peroxide fusion digestion and the SRAT Receipt and SRAT Product elemental concentrations obtained via the DWPF CC method provide insight into the adequacy of the CC method for analysis of the SRAT Product. The DWPF lab would need to calcine the SRAT product at 1050 C for the best comparison. If a consistent difference in elemental concentrations is revealed, another type of digestion (i.e. sodium peroxide/hydroxide fusion) should be used to determine the concentration of the element in question. Particular emphasis should be placed on monitoring the aluminum concentration in SB5

  15. Batched Triangular DLA for Very Small Matrices on GPUs

    Charara, Ali; Keyes, David E.; Ltaief, Hatem

    2017-01-01

    linear algebra operations on very small matrix sizes (usually less than 100). Batched dense linear algebra kernels are becoming ubiquitous for such scientific computations. Within a single API call, these kernels are capable of simultaneously launching a

  16. Groundwater arsenic remediation using zerovalent iron: Batch and column tests

    Recently, increasing efforts have been made to explore the applicability and limitations of zerovalent iron (Fe0) for the treatment of arsenicbearing groundwater and wastewater. The experimental batch and column tests have demonstrated that arsenate and arsenite are removed effec...

  17. Batch Adsorption Study of Methylene Blue in Aqueous Solution ...

    PROF HORSFALL

    of methylene blue (azo dye) from the synthetic industrial wastewater was investigated in a batch system. Rice husk and coconut shell were ... the textiles, rubber, paper, plastics, cosmetic, and .... wastewater by. Fenton's oxidation: Kinetic study.

  18. Automated batch emulsion copolymerization of styrene and butyl acrylate

    Mballa Mballa, M.A.; Schubert, U.S.; Heuts, J.P.A.; Herk, van A.M.

    2011-01-01

    This article describes a method for carrying out emulsion copolymerization using an automated synthesizer. For this purpose, batch emulsion copolymerizations of styrene and butyl acrylate were investigated. The optimization of the polymerization system required tuning the liquid transfer method,

  19. development of an automated batch-process solar water disinfection

    user

    This work presents the development of an automated batch-process water disinfection system ... Locally sourced materials in addition to an Arduinomicro processor were used to control ..... As already mentioned in section 3.1.1, a statistical.

  20. Numerical modeling of batch formation in waste incineration plants

    Obroučka Karel

    2015-03-01

    Full Text Available The aim of this paper is a mathematical description of algorithm for controlled assembly of incinerated batch of waste. The basis for formation of batch is selected parameters of incinerated waste as its calorific value or content of pollutants or the combination of both. The numerical model will allow, based on selected criteria, to compile batch of wastes which continuously follows the previous batch, which is a prerequisite for optimized operation of incinerator. The model was prepared as for waste storage in containers, as well as for waste storage in continuously refilled boxes. The mathematical model was developed into the computer program and its functionality was verified either by practical measurements or by numerical simulations. The proposed model can be used in incinerators for hazardous and municipal waste.

  1. 40 CFR 63.462 - Batch cold cleaning machine standards.

    2010-07-01

    .... (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with the... cleaning machine complying with paragraph (a)(2) or (b) of this section shall comply with the work and...

  2. Mechanical relaxation in glasses

    Hiki, Y.

    2004-01-01

    The basic properties of glasses and the characteristics of mechanical relaxation in glasses were briefly reviewed, and then our studies concerned were presented. Experimental methods adopted were viscosity, internal friction, ultrasonic attenuation, and Brillouin scattering measurements. The specimens used were several kinds of inorganic, organic, and metallic glasses. The measurements were mainly carried out from the room temperature up to the glass transition temperature, and the relaxation time was determined as a function of temperature. The 'double relaxation' composed of two Arrhenius-type relaxations was observed in many materials. In both relaxations, the 'compensation effect' showing a correlation of the pre-exponential factor and the activation energy was observed. These results were explained by considering the 'complex relaxation' due to cooperative motions of atoms or group of atoms. Values of activation energy near the glass transition determined by the various experimental methods were compared with each other

  3. Polymorphism in glasses

    Landa, L.M.; Nikolaeva, I.N.

    1979-01-01

    To defect phase interfaces and spasmodic properties change, the inhomogeneity and the second radiation effects in quartz glass, metamict phase and intermediate states have been investigated. When irradiating with fast neutrons the transformation of quartz glass - metamict phase occurs completely. The transformation is completed at 2x10 20 part./cm 2 dose. Thermal treatment not only increases the number of inhomogeneities but also results in increasing quartz glass density. Annealing transforms the metamict phase into common quartz glass at 1400 K. The fact, that thermal treatment results in the complete transformation of metamict phase into quartz glass, and the inverse transformation occurs only partially, is quite regular, as the metamict phase has a lesser entropy and is a more ordered state. It is shown that different amorphous phases of a chemical composition have different structures and properties, that there are interfaces between them, and the transformation from one state to another in microvolumes is realized spasmodically and requires expenditure of energy

  4. Moessbauer effect and infrared study of some borate glass containing Mn and Fe oxides

    Gabr, M.

    2005-01-01

    Lithium borate glasses containing transition metals appeared now of very high technological and scientific interest. Therefore some lithium borate glasses containing mixed transition metal ions (manganese and iron) were investigated. The glass batches were melted at 1250 degree C for three hours and annealed at 350 degree C -over night- to obtain strain free glasses. Moessbauer Effect spectroscopy and Infrared analysis were employed to investigate the structural changes due to the change of their batches composition. Differential thermal analysis, magnetic susceptibility, density and molar volume measurements were also performed to study the effect of changing both manganese and iron oxides at the expense of boron oxide on these properties. Infrared analysis indicated the presence of different structural groups such as BO 3 , BO 4 , FeO 4 and MnO 6 as well as different vibrations indicated the presence of various bonds in the glass network. The values of the characteristic temperatures (T g , T c and T m ) showed gradual increase except those of the last sample where they showed a decrease. The mid sample showed the lowest stability value. It was found that the molar volume showed its highest value at R=0.33 [where R is the ratio of glass network modifier to the glass network former]. After that it showed gradual linear decrease. The magnetic susceptibility measurements showed approximately stable value between R=0.29 and 0.33, then it increased up to R=0.38, and after that, it decreased up to R= 0.43. The obtained magnetic susceptibility values indicated that all these glasses are paramagnetic. The obtained Moessbauer spectra and the calculated parameters confirmed that iron ions participated in the glass network as network former cations. It confirmed also that all glasses reflect paramagnetic character. The observed structural change were explained and correlated with the change of the measured physical properties

  5. Parameters of Concrete Modified with Glass Meal and Chalcedonite Dust

    Kotwa, Anna

    2017-10-01

    Additives used for production of concrete mixtures affect the rheological properties and parameters of hardened concrete, including compressive strength, water resistance, durability and shrinkage of hardened concrete. By their application, the use of cement and production costs may be reduced. The scheduled program of laboratory tests included preparation of six batches of concrete mixtures with addition of glass meal and / or chalcedonite dust. Mineral dust is a waste product obtained from crushed aggregate mining, with grain size below 0,063μm. The main ingredient of chalcedonite dust is silica. Glass meal used in the study is a material with very fine grain size, less than 65μm. This particle size is present in 60% - 90% of the sample. Additives were used to replace cement in concrete mixes in an amount of 15% and 25%. The amount of aggregate was left unchanged. The study used Portland cement CEM I 42.5R. Concrete mixes were prepared with a constant rate w / s = 0.4. The aim of the study was to identify the effect of the addition of chalcedonite dust and / or glass meal on the parameters of hardened concrete, i.e. compressive strength, water absorption and capillarity. Additives used in the laboratory tests significantly affect the compressive strength. The largest decrease in compressive strength of concrete samples was recorded for samples with 50% substitutes of cement additives. This decrease is 34.35%. The smallest decrease in compressive strength was noted in concrete with the addition of 15% of chalcedonite dust or 15% glass meal, it amounts to an average of 15%. The study of absorption shows that all concrete with the addition of chalcedonite dust and glass meal gained a percentage weight increase between 2.7 ÷ 3.1% for the test batches. This is a very good result, which is probably due to grout sealing. In capillary action for the test batches, the percentage weight gains of samples ranges from 4.6% to 5.1%. However, the reference concrete obtained

  6. Dynamic Extensions of Batch Systems with Cloud Resources

    Hauth, T; Quast, G; Büge, V; Scheurer, A; Kunze, M; Baun, C

    2011-01-01

    Compute clusters use Portable Batch Systems (PBS) to distribute workload among individual cluster machines. To extend standard batch systems to Cloud infrastructures, a new service monitors the number of queued jobs and keeps track of the price of available resources. This meta-scheduler dynamically adapts the number of Cloud worker nodes according to the requirement profile. Two different worker node topologies are presented and tested on the Amazon EC2 Cloud service.

  7. Application of the fuzzy theory to simulation of batch fermentation

    Filev, D P; Kishimoto, M; Sengupta, S; Yoshida, T; Taguchi, H

    1985-12-01

    A new approach for system identification with a linguistic model of batch fermentation processes is proposed. The fuzzy theory was applied in order to reduce the uncertainty of quantitative description of the processes by use of qualitative characteristics. An example of fuzzy modeling was illustrated in the simulation of batch ethanol production from molasses after interpretation of the new method, and extension of the fuzzy model was also discussed for several cases of different measurable variables.

  8. Glass leaching performance

    Chick, L.A.; Turcotte, R.P.

    1983-05-01

    Current understanding of the leaching performance of high-level nuclear waste (HLW) glass is summarized. The empirical model of waste glass leaching behavior developed shows that at high water flow rates the glass leach rate is kinetically limited to a maximum value. At intermediate water flow rates, leaching is limited by the solution concentration of silica and decreases with decreasing water flow rates. Release of soluble elements is controlled by silica dissolution because silica forms the binding network of the glass. At low water flow rates, mass loss rates reach values controlled by formation rates of alteration minerals, or by diffusion of dissolution products through essentially stagnant water. The parameters reviewed with respect to their quantifiable influence on leaching behavior include temperature, pH, leachant composition, glass composition, thermal history, and radiation. Of these, temperature is most important since the rate of mass loss approximately doubles with each 10 0 C increase in dilute solutions. The pH has small effects within the 4 to 10 range. The chemical composition of the leachant is most important with regard to its influence on alteration product formation. Glass composition exhibits the largest effects at high flow rates where improved glasses leach from ten to thirty times slower than glass 76 to 68. The effects of the thermal history (devitrification) of the glass are not likely to be significant. Radiation effects are important primarily in that radiolysis can potentially drive pH values to less than 4. Radiation damage to the glass causes insignificant changes in leaching performance

  9. Polynomial Batch Codes for Efficient IT-PIR

    Henry Ryan

    2016-10-01

    Full Text Available Private information retrieval (PIR is a way for clients to query a remote database without the database holder learning the clients’ query terms or the responses they generate. Compelling applications for PIR are abound in the cryptographic and privacy research literature, yet existing PIR techniques are notoriously inefficient. Consequently, no such PIRbased application to date has seen real-world at-scale deployment. This paper proposes new “batch coding” techniques to help address PIR’s efficiency problem. The new techniques exploit the connection between ramp secret sharing schemes and efficient information-theoretically secure PIR (IT-PIR protocols. This connection was previously observed by Henry, Huang, and Goldberg (NDSS 2013, who used ramp schemes to construct efficient “batch queries” with which clients can fetch several database records for the same cost as fetching a single record using a standard, non-batch query. The new techniques in this paper generalize and extend those of Henry et al. to construct “batch codes” with which clients can fetch several records for only a fraction the cost of fetching a single record using a standard non-batch query over an unencoded database. The batch codes are highly tuneable, providing a means to trade off (i lower server-side computation cost, (ii lower server-side storage cost, and/or (iii lower uni- or bi-directional communication cost, in exchange for a comparatively modest decrease in resilience to Byzantine database servers.

  10. A parametric study ot protease production in batch and fed-batch cultures of Bacillus firmus.

    Moon, S H; Parulekar, S J

    1991-03-05

    Proteolytic enzymes produced by Bacillus species find a wide variety of applications in brewing, detergent, food, and leather industries. Owing to significant differences normally observed in culture conditions promoting cell growth and those promoting production of metabolites such as enzymes, for increased efficacy of bioreactor operations it is essential to identify these sets of conditions (including medium formulation). This study is focused on formulation of a semidefined medium that substantially enhances synthesis and secretion of an alkaline protease in batch cultures of Bacillus firmus NRS 783, a known superior producer of this enzyme. The series of experiments conducted to identify culture conditions that lead to improved protease production also enables investigation of the regulatory effects of important culture parameters including pH, dissolved oxygen, and concentrations of nitrogen and phosphorous sources and yeast extract in the medium on cell growth, synthesis and secretion of protease, and production of two major nonbiomass products, viz., acetic acid and ethanol. Cell growth and formation of the three nonbiomass products are hampered significantly under nitrogen, phosphorous, or oxygen limitation, with the cells being unable to grow in an oxygen-free environment. Improvement in protease production is achieved with respect to each culture parameter, leading in the process to 80% enhancement in protease activity over that attained using media reported in the literature. Results of a few fed-batch experiments with constant feed rate, conducted to examine possible enhancement in protease production and to further investigate repression of protease synthesis by excess of the principal carbon and nitrogen sources, are also discussed. The detailed investigation of stimulatory and repressory effects of simple and complex nutrients on protease production and metabolism of Bacillus firmus conducted in this study will provide useful guidelines for design

  11. Materials analyses of ceramics for glass furnace recuperators

    Weber, G.W.; Tennery, V.J.

    1979-11-01

    The use of waste heat recuperation systems offers significant promise for meaningful energy conservation in the process heat industries. This report details the analysis of candidate ceramic recuperator materials exposed to simulated industrial glass furnace hot flue gas environments. Several candidate structural ceramic materials including various types of silicon carbide, several grades of alumina, mullite, cordierite, and silicon nitride were exposed to high-temperature flue gas atmospheres from specially constructed day tank furnaces. Furnace charging, operation, and batch composition were selected to closely simulate industrial practice. Material samples were exposed in flues both with and without glass batch in the furnace for times up to 116 d at temperatures from 1150 to 1550/sup 0/C (2100 to 2800/sup 0/F). Exposed materials were examined by optical microscopy, scanning electron microscopy, energy dispersive x-ray analysis, x-ray diffraction, and x-ray fluorescence to identify material degradation mechanisms. The materials observations were summarized as: Silicon carbide exhibited enhanced corrosion at lower temperatures (1150/sup 0/C) when alkalies were deposited on the carbide from the flue gas and less corrosion at higher temperatures (1550/sup 0/C) when alkalies were not deposited on the carbide; alumina corrosion depended strongly upon purity and density and alumina contents less than 99.8% were unsatisfactory above 1400/sup 0/C; and mullite and cordierite are generally unacceptable for application in soda-lime glass melting environments at temperatures above 1100/sup 0/C.

  12. Batch-to-Batch Quality Consistency Evaluation of Botanical Drug Products Using Multivariate Statistical Analysis of the Chromatographic Fingerprint

    Xiong, Haoshu; Yu, Lawrence X.; Qu, Haibin

    2013-01-01

    Botanical drug products have batch-to-batch quality variability due to botanical raw materials and the current manufacturing process. The rational evaluation and control of product quality consistency are essential to ensure the efficacy and safety. Chromatographic fingerprinting is an important and widely used tool to characterize the chemical composition of botanical drug products. Multivariate statistical analysis has showed its efficacy and applicability in the quality evaluation of many ...

  13. Thermal Conductivity of Foam Glass

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    Due to the increased focus on energy savings and waste recycling foam glass materials have gained increased attention. The production process of foam glass is a potential low-cost recycle option for challenging waste, e.g. CRT glass and industrial waste (fly ash and slags). Foam glass is used...... as thermal insulating material in building and chemical industry. The large volume of gas (porosity 90 – 95%) is the main reason of the low thermal conductivity of the foam glass. If gases with lower thermal conductivity compared to air are entrapped in the glass melt, the derived foam glass will contain...... only closed pores and its overall thermal conductivity will be much lower than that of the foam glass with open pores. In this work we have prepared foam glass using different types of recycled glasses and different kinds of foaming agents. This enabled the formation of foam glasses having gas cells...

  14. Durability of glasses from the Hg-doped Integrated DWPF Melter System (IDMS) campaign

    Jantzen, C.M.

    1992-01-01

    The Integrated DWPF Melter System (IDMS) for the vitrification of high-level radioactive wastes is designed and constructed to be a 1/9th scale prototype of the full scale Defense Waste Processing Facility (DWPF) melter. The IDMS facility is the first engineering scale melter system capable of processing mercury, and flowsheet levels of halides and noble metals. In order to determine the effects of mercury on the feed preparation process, the off-gas chemistry, glass melting behavior, and glass durability, a three-run mercury (Hg) campaign was conducted. The glasses produced during the Hg campaign were composed of Batch 1 sludge, simulated precipitate hydrolysis aqueous product (PHA) from the Precipitate Hydrolysis Experimental Facility (PHEF), and Frit 202. The glasses were produced using the DWPF process/product models for glass durability, viscosity, and liquidus. The durability model indicated that the glasses would all be more durable than the glass qualified in the DWPF Environmental Assessment (EA). The glass quality was verified by performing the Product Consistency Test (PCT) which was designed for glass durability testing in the DWPF

  15. Effect of different glasses in glass bonded zeolite

    Lewis, M.A.; Ackerman, J.P.; Verma, S.

    1995-01-01

    A mineral waste form has been developed for chloride waste salt generated during the pyrochemical treatment of spent nuclear fuel. The waste form consists of salt-occluded zeolite powders bound within a glass matrix. The zeolite contains the salt and immobilizes the fission products. The zeolite powders are hot pressed to form a mechanically stable, durable glass bonded zeolite. Further development of glass bonded zeolite as a waste form requires an understanding of the interaction between the glass and the zeolite. Properties of the glass that enhance binding and durability of the glass bonded zeolite need to be identified. Three types of glass, boroaluminosilicate, soda-lime silicate, and high silica glasses, have a range of properties and are now being investigated. Each glass was hot pressed by itself and with an equal amount of zeolite. MCC-1 leach tests were run on both. Soda-lime silicate and high silica glasses did not give a durable glass bonded zeolite. Boroaluminosilicate glasses rich in alkaline earths did bind the zeolite and gave a durable glass bonded zeolite. Scanning electron micrographs suggest that the boroaluminosilicate glasses wetted the zeolite powders better than the other glasses. Development of the glass bonded zeolite as a waste form for chloride waste salt is continuing

  16. Oxynitride glasses: a review

    Garcia, A.R.; Clausell, C.; Barba, A.

    2016-07-01

    Oxynitride glasses are special types of silicates or silicoaluminates which have been the object of many studies over the last forty years. They can be prepared by means of various complex methods, leading to variable levels of nitrogen incorporation, though in all cases giving limited transparency in the visible range. More recently, a new family of oxynitride glasses incorporating fluorine has been investigated. This paper outlines the effect of composition, in particular nitrogen and fluorine content, on properties such as glass transition temperature, hardness, Young's modulus, compactness and molar volume. (Author)

  17. Orbital glass in HTSC

    Kusmartsev, F.V.

    1992-10-01

    The physical reasons why the orbital glass may exist in granular high-temperature superconductors and the existing experimental data appeared recently are discussed. The orbital glass is characterized by the coexistence of the orbital paramagnetic state with the superconducting state and occurs at small magnetic fields H c0 c1 . The transition in orbital glass arises at the critical field H c0 which is inversely proportional to the surface cross-area S of an average grain. In connection with theoretical predictions the possible experiments are proposed. (author). 10 refs

  18. Bioactive glasses and glass-ceramics

    de Aza, P. N.

    2007-04-01

    Full Text Available Since the late 1960´s, a great interest in the use of bioceramic materials for biomedical applications has been developed. In a previous paper, the authors reviewed crystalline bioceramic materials “sensus stricto”, it is to say, those ceramic materials, constituted for non-metallic inorganic compounds, crystallines and consolidates by thermal treatment of powders at high temperature. In the present review, the authors deal with those called bioactive glasses and glassceramics. Although all of them are also obtained by thermal treatment at high temperature, the first are amorphous and the second are obtained by devitrification of a glass, although the vitreous phase normally prevails on the crystalline phases. After an introduction to the concept of bioactive materials, a short historical review of the bioactive glasses development is made. Its preparation, reactivity in physiological media, mechanism of bonding to living tissues and mechanical strength of the bone-implant interface is also reported. Next, the concept of glass-ceramic and the way of its preparation are exposed. The composition, physicochemical properties and biological behaviour of the principal types of bioactive glasses and glass-ceramic materials: Bioglass®, Ceravital®, Cerabone®, Ilmaplant® and Bioverit® are also reviewed. Finally, a short review on the bioactive-glass coatings and bioactive-composites and most common uses of bioactive-glasses and glass-ceramics are carried out too.

    Desde finales de los años sesenta, se ha despertado un gran interés por el uso de los materiales biocerámicos para aplicaciones biomédicas. En un trabajo previo, los autores hicieron una revisión de los denominados materiales biocerámicos cristalinos en sentido estricto, es decir, de aquellos materiales, constituidos por compuestos inorgánicos no metálicos, cristalinos y consolidados mediante tratamientos térmicos a altas temperaturas. En el presente trabajo, los autores

  19. Fun with Singing Wine Glasses

    Boone, Christine; Galloway, Melodie; Ruiz, Michael J.

    2018-01-01

    A fun activity is presented using singing wine glasses for introductory physics students. Students tune a white wine glass and a red wine glass to as many semitones as possible by filling the glasses with the appropriate amounts of water. A smart phone app is used to measure the frequencies of equal-temperament tones. Then plots of frequency…

  20. Waste glass weathering

    Bates, J.K.; Buck, E.C.

    1994-01-01

    The weathering of glass is reviewed by examining processes that affect the reaction of commercial, historical, natural, and nuclear waste glass under conditions of contact with humid air and slowly dripping water, which may lead to immersion in nearly static solution. Radionuclide release data from weathered glass under conditions that may exist in an unsaturated environment are presented and compared to release under standard leaching conditions. While the comparison between the release under weathering and leaching conditions is not exact, due to variability of reaction in humid air, evidence is presented of radionuclide release under a variety of conditions. These results suggest that both the amount and form of radionuclide release can be affected by the weathering of glass

  1. Super ionic conductive glass

    Susman, S.; Volin, K.J.

    Described is an ionically conducting glass for use as a solid electrolyte in a power or secondary cell containing an alkali metal-containing anode and a cathode separated by an alkali metal ion conducting glass having an ionic transference number of unity and the general formula: A/sub 1 + x/D/sub 2-x/3/Si/sub x/P/sub 3 - x/O/sub 12 - 2x/3/, wherein A is a network modifier for the glass and is an alkali metal of the anode, D is an intermediate for the glass and is selected from the class consisting of Zr, Ti, Ge, Al, Sb, Be, and Zn and X is in the range of from 2.25 to 3.0. Of the alkali metals, Na and Li are preferred and of the intermediate, Zr, Ti and Ge are preferred.

  2. Phosphate glasses, containing nitrogen

    Lisitsyna, E.A.; Khalilev, V.D.; Koryavin, A.A.; Goncharova, L.N.

    1987-01-01

    Possibilities of nitrogen-containing glass synthesis by the introduction into the charge of ammonium salts, as well as aluminium nitride, are studied. Zinc alumoyttrium phosphate glass (mol. %) Zn(PO 3 ) 2 - 4O, Al(PO 3 ) 3 - 3O, Y(PO 3 ) 3 -3O is suggested as a matrix. It is shown that the effect of amide and imide groups on the properties of the glass is less noticeable than the effect of nitride groups. Direct introduction of nitride constituent was realized using AlN, but aluminium introduction was taken into account so that the oxide was subtracted. The attempt to introduce more than 2.5 mass % of nitrogen into initial matrix by aluminium nitride has failed due to repeated restoration of glass with amorphous phosphorus isolation

  3. SLUDGE MASS REDUCTION: PRIMARY COMPOSITIONAL FACTORS THAT INFLUENCE MELT RATE FOR FUTURE SLUDGE BATCH PROJECTIONS

    Newell, J; Miller, D; Stone, M; Pickenheim, B

    2008-01-01

    The Savannah River National Laboratory (SRNL) was tasked to provide an assessment of the downstream impacts to the Defense Waste Processing Facility (DWPF) of decisions regarding the implementation of Al-dissolution to support sludge mass reduction and processing. Based on future sludge batch compositional projections from the Liquid Waste Organization's (LWO) sludge batch plan, assessments have been made with respect to the ability to maintain comparable projected operating windows for sludges with and without Al-dissolution. As part of that previous assessment, candidate frits were identified to provide insight into melt rate for average sludge batches representing with and without Al-dissolution flowsheets. Initial melt rate studies using the melt rate furnace (MRF) were performed using five frits each for Cluster 2 and Cluster 4 compositions representing average without and with Al-dissolution. It was determined, however, that the REDOX endpoint (Fe 2+ /ΣFe for the glass) for Clusters 2 and 4 resulted in an overly oxidized feed which negatively affected the initial melt rate tests. After the sludge was adjusted to a more reduced state, additional testing was performed with frits that contained both high and low concentrations of sodium and boron oxides. These frits were selected strictly based on the ability to ascertain compositional trends in melt rate and did not necessarily apply to any acceptability criteria for DWPF processing. The melt rate data are in general agreement with historical trends observed at SRNL and during processing of SB3 (Sludge Batch 3)and SB4 in DWPF. When MAR acceptability criteria were applied, Frit 510 was seen to have the highest melt rate at 0.67 in/hr for Cluster 2 (without Al-dissolution), which is compositionally similar to SB4. For Cluster 4 (with Al-dissolution), which is compositionally similar to SB3, Frit 418 had the highest melt rate at 0.63 in/hr. Based on this data, there appears to be a slight advantage of the Frit

  4. Reducing the effects of X-ray pre-heat in double shell NIF capsules by over-coating the high Z shell

    Wilson, Douglas; Milovich, J. L.; Daughton, W. S.; Loomis, E. N.; Sauppe, J. P.; Dodd, E. S.; Merritt, E. C.; Montgomery, D. S.; Renner, D. B.; Haines, B. M.; Cardenas, T.; Desjardins, T.; Palaniyappan, S.; Batha, S. H.

    2017-10-01

    Hohlraum generated X-rays will penetrate the ablator of a double shell capsule and be absorbed in the outer surface of the inner capsule. The ablative pressure this generates drives a shock into the central fuel, and a reflected shock that reaches the inner high-Z shell surface before the main shock even enters the fuel. With a beryllium over-coat preheat X-rays deposit just inside the beryllium/high z interface. The beryllium tamps the preheat expansion, eliminating ablation, and dramatically reducing pressure. The slow shock or pressure wave it generates is then overtaken by the main shock, avoiding an early shock in the fuel and increasing capsule yield.

  5. Exploiting the use of compact heat exchangers on preheating trains; Avaliacao de desempenho de trocadores compactos em bateria de pre-aquecimento - REDUC

    Villas Boas, Alan Trugilho; Bolsoni, Adair [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Refinaria de Duque de Caxias (REDUC); Kuboski, Claudio; Cesario, Diomedes [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2008-07-01

    The U-1210 distillation unit of Holding has being expected to suffer a metallurgical adaptation in order to process petroleum with higher naphthenic acids concentration. A heat integration study (pinch analysis) was realized, with the restriction of limited plot area and shut-down time. A full compabloc preheat train was preliminary concept. During conceptual design, REDUC found it to be a good idea to have a performance test. A compabloc CP30 unit has been installed, in order to evaluate the performance of this equipment under unit conditions. The operation service chosen was vacuum residue preheating crude before the dessalter, low crude temperature (100 deg C to 115 deg C). The objective was operational and maintenance experience. (author)

  6. Characterizing the residual glass in a MgO/Al2O3/SiO2/ZrO2/Y2O3 glass-ceramic

    Seidel, Sabrina; Patzig, Christian; Wisniewski, Wolfgang; Gawronski, Antje; Hu, Yongfeng; Höche, Thomas; Rüssel, Christian

    2016-01-01

    The non-isochemical crystallization of glasses leads to glass-ceramics in which the chemical composition of the amorphous matrix differs from that of the parent glass. It is challenging to solely analyse the properties of these residual glassy phases because they frequently contain finely dispersed crystals. In this study, the composition of the residual glass matrix after the crystallization of a glass with the mol% composition 50.6 SiO2 · 20.7 MgO · 20.7 Al2O3 · 5.6 ZrO2 · 2.4 Y2O3 is analysed by scanning transmission electron microscopy (STEM) including energy dispersive X-ray analysis (EDXS). A batch of the residual glass with the determined composition is subsequently melted and selected properties are analysed. Furthermore, the crystallization behaviour of this residual glass is studied by X-ray diffraction, scanning electron microscopy including electron backscatter diffraction and STEM-EDXS analyses. The residual glass shows sole surface crystallization of indialite and multiple yttrium silicates while bulk nucleation does not occur. This is in contrast to the crystallization behaviour of the parent glass, in which a predominant bulk nucleation of spinel and ZrO2 is observed. The crystallization of the residual glass probably leads to different crystalline phases when it is in contact to air, rather than when it is enclosed within the microstructure of the parent glass-ceramics. PMID:27734918

  7. Baseline LAW Glass Formulation Testing

    Kruger, Albert A.; Mooers, Cavin; Bazemore, Gina; Pegg, Ian L.; Hight, Kenneth; Lai, Shan Tao; Buechele, Andrew; Rielley, Elizabeth; Gan, Hao; Muller, Isabelle S.; Cecil, Richard

    2013-01-01

    The major objective of the baseline glass formulation work was to develop and select glass formulations that are compliant with contractual and processing requirements for each of the LAW waste streams. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, development of glass formulations to support ILAW qualification activities, and identification of glass formulation issues with respect to contract specifications and processing requirements

  8. Origins and Scaling of Hot-Electron Preheat in Ignition-Scale Direct-Drive Inertial Confinement Fusion Experiments.

    Rosenberg, M J; Solodov, A A; Myatt, J F; Seka, W; Michel, P; Hohenberger, M; Short, R W; Epstein, R; Regan, S P; Campbell, E M; Chapman, T; Goyon, C; Ralph, J E; Barrios, M A; Moody, J D; Bates, J W

    2018-02-02

    Planar laser-plasma interaction (LPI) experiments at the National Ignition Facility (NIF) have allowed access for the first time to regimes of electron density scale length (∼500 to 700  μm), electron temperature (∼3 to 5 keV), and laser intensity (6 to 16×10^{14}  W/cm^{2}) that are relevant to direct-drive inertial confinement fusion ignition. Unlike in shorter-scale-length plasmas on OMEGA, scattered-light data on the NIF show that the near-quarter-critical LPI physics is dominated by stimulated Raman scattering (SRS) rather than by two-plasmon decay (TPD). This difference in regime is explained based on absolute SRS and TPD threshold considerations. SRS sidescatter tangential to density contours and other SRS mechanisms are observed. The fraction of laser energy converted to hot electrons is ∼0.7% to 2.9%, consistent with observed levels of SRS. The intensity threshold for hot-electron production is assessed, and the use of a Si ablator slightly increases this threshold from ∼4×10^{14} to ∼6×10^{14}  W/cm^{2}. These results have significant implications for mitigation of LPI hot-electron preheat in direct-drive ignition designs.

  9. Origins and Scaling of Hot-Electron Preheat in Ignition-Scale Direct-Drive Inertial Confinement Fusion Experiments

    Rosenberg, M. J.; Solodov, A. A.; Myatt, J. F.; Seka, W.; Michel, P.; Hohenberger, M.; Short, R. W.; Epstein, R.; Regan, S. P.; Campbell, E. M.; Chapman, T.; Goyon, C.; Ralph, J. E.; Barrios, M. A.; Moody, J. D.; Bates, J. W.

    2018-01-01

    Planar laser-plasma interaction (LPI) experiments at the National Ignition Facility (NIF) have allowed access for the first time to regimes of electron density scale length (˜500 to 700 μ m ), electron temperature (˜3 to 5 keV), and laser intensity (6 to 16 ×1014 W /cm2 ) that are relevant to direct-drive inertial confinement fusion ignition. Unlike in shorter-scale-length plasmas on OMEGA, scattered-light data on the NIF show that the near-quarter-critical LPI physics is dominated by stimulated Raman scattering (SRS) rather than by two-plasmon decay (TPD). This difference in regime is explained based on absolute SRS and TPD threshold considerations. SRS sidescatter tangential to density contours and other SRS mechanisms are observed. The fraction of laser energy converted to hot electrons is ˜0.7 % to 2.9%, consistent with observed levels of SRS. The intensity threshold for hot-electron production is assessed, and the use of a Si ablator slightly increases this threshold from ˜4×10 14 to ˜6 ×1014 W /cm2 . These results have significant implications for mitigation of LPI hot-electron preheat in direct-drive ignition designs.

  10. Effects of consolidation process on microstructure and mechanical properties of commingled glass/polypropylene composites

    Tufail, M.; Long, A.C.; Rudd, C.D.

    2001-01-01

    The thermal history of a thermoplastic composite material during forming and consolidation is critical to the quality of the component. Attempts to process outside the normal melt region will result in incomplete consolidation and voidage. Clearly then, the preheat phase plays a key role in successful processing. Too low a preheat temperature results in insufficient matrix flow while, if the temperature is increased too much, degradation of the matrix occurs, again resulting in poor quality of the composite. In particular polypropylene has poor chemical (oxidative) resistance, and oxidative degradation reduces the average molecular weight of the materials. If excessive, this can result in a dramatic reduction in mechanical properties. Flat plaques of braided, commingled glass/polypropylene yarn were produced to examine these effects using both isothermal and non-isothermal consolidation. Woven plaques were also produced from commingled yarn in a similar fashion as control samples in order to identify any effects specific to the braiding process. This paper describes the effect of heating and stamping cycles on the properties of these composites, concentrating on the effects of temperature, heating time and compaction rate. (author)

  11. Cloning, multicopy expression and fed-batch production of Rhodotorula araucariae epoxide hydrolase in yarrowia lipolytica

    Ramduth, D

    2008-05-01

    Full Text Available demonstrated a 4 fold enhanced EH activity over the transformant. The transformant was then evaluated in batch and fed batch fermentations, where the batch fermentations resulted in - 50% improved EH activity from flask evaluations. In fed batch fermentations...

  12. A method to minimise the fading effects of LiF:Mg,Ti (TLD-600 and TLD-700) using a pre-heat technique.

    Lee, YoungJu; Won, Yuho; Kang, Kidoo

    2015-04-01

    Passive integrating dosemeters [thermoluminescent dosimeter (TLD) and optically stimulated luminescence (OSL)] are the only legally permitted individual dosemeters for occupational external radiation exposure monitoring in Korea. Also its maximum issuing cycle does not exceed 3 months, and the Korean regulations require personal dosemeters for official assessment of external radiation exposure to be issued by an approved or rather an accredited dosimetry service according to ISO/IEC 17025. KHNP (Korea Hydro & Nuclear Power, LTD), a unique operating company of nuclear power plants (NPPs) in Korea, currently has a plan to extend a TLD issuing cycle from 1 to 3 months under the authors' fading error criteria, ±10%. The authors have performed a feasibility study that minimises post-irradiation fading effects within their maximum reading cycle employing pre-heating technique. They repeatedly performed irradiation/reading a bare TLD chip to determine optimum pre-heating conditions by analysing each glow curve. The optimum reading conditions within the maximum reading cycle of 3 months were decided: a pre-heating temperature of 165°C, a pre-heating time of 9 s, a heating rate of 25°C s(-1), a reading temperature of 300°C and an acquisition time of 10 s. The fading result of TLD-600 and TLD-700 carried by newly developed time temperature profile (TTP) showed a much smaller fading effect than that of current TTP. The result showed that the fading error due to a developed TTP resulted in a ∼5% signal loss, whereas a current TTP caused a ∼15% loss. The authors also carried out a legal performance test on newly developed TTP to confirm its possibility as an official dosemeter. The legal performance tests that applied the developed TTP satisfied the criteria for all the test categories. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Establishment of a dosimetric system for high doses using glasses

    Correa Quezada, Valeria de la Asuncion

    1997-01-01

    A routine dosimetric system was developed using commercial glass samples. The dosimetric characteristics of national and imported samples were studied: batch uniformity, response repeatability, reutilization, absorbed dose response, detection range, response stability as a function of absorbed dose, storage temperature and thermal treatments pre- and post-irradiation, using the optical absorption technique. As an application, the dosimetric system was tested in a flower irradiation process at IPEN. All the obtained results show the usefulness of the proposed system for high dose dosimetry. (author)

  14. The study on pre-heat conditions in the equivalent-dose estimation of holocene loess using the single-aliquot regenerative-dose (SAR) protocol

    Jia Yaofeng; Huang Chunchang; Pang Jiangli; Lu Xinwei; Zhang Xu

    2008-01-01

    The thermal treatment in the equivalent-dose estimation often is carried in the OSL dating, and pre-heat is a main thermal treatment. Due to which will originate the problems of thermal transfer and thermal activation, the thermal treatment and the setup of their conditions are key problems influencing the accuracy of OSL dating. The paper combined the temperature of pre-heat and cut-heat used in the routine measurement of IRSL and Post-IR OSL, and then estimated the equivalent-dose of several loess samples. The estimated result presents that the equivalent-dose depends on the heat temperature, especially depends on the cut-heat temperature, which is to say that the equivalent-dose increases with the cut-heat temperature; a plateau of equivalent-dose appears when using the 200-240 degree C cut-heat in the range of 200-300 degree C pre-heat, and the equivalent-doses estimated by IRSL and Post-IR OSL respectively are close to each other, which resulted from the similar sensitivity change direction of optical stimulated signals and its smaller change range in the measurement cycles using the combined temperature of pre- heat and cut-heat, and the incomplete calibration of sensitivity change of optical stimulated signals in the whole measurement cycles caused the variation of estimated equivalent-dose corresponding to the cut-heat temperature. (authors)

  15. Wastes based glasses and glass-ceramics

    Barbieri, L.

    2001-12-01

    Full Text Available Actually, the inertization, recovery and valorisation of the wastes coming from municipal and industrial processes are the most important goals from the environmental and economical point of view. An alternative technology capable to overcome the problem of the dishomogeneity of the raw material chemical composition is the vitrification process that is able to increase the homogeneity and the constancy of the chemical composition of the system and to modulate the properties in order to address the reutilization of the waste. Moreover, the glasses obtained subjected to different controlled thermal treatments, can be transformed in semy-cristalline material (named glass-ceramics with improved properties with respect to the parent amorphous materials. In this review the tailoring, preparation and characterization of glasses and glass-ceramics obtained starting from municipal incinerator grate ash, coal and steel fly ashes and glass cullet are described.

    Realmente la inertización, recuperación y valorización de residuos que proceden de los procesos de incineración de residuos municipales y de residuos industriales son metas importantes desde el punto de vista ambiental y económico. Una tecnología alternativa capaz de superar el problema de la heterogeneidad de la composición química de los materiales de partida es el proceso de la vitrificación que es capaz de aumentar la homogeneidad y la constancia de la composición química del sistema y modular las propiedades a fin de la reutilización del residuo. En este artículo se presentan los resultados de vitrificación en que los vidrios fueron sometidos a tratamientos térmicos controlados diferentes, de manera que se transforman en materiales semicristalinos (también denominados vitrocerámicos con mejores propiedades respecto a los materiales amorfos originales. En esta revisión se muestra el diseño, preparación y caracterización de vidrios y vitrocerámicos partiendo de

  16. Application of gain scheduling to the control of batch bioreactors

    Cardello, Ralph; San, Ka-Yiu

    1987-01-01

    The implementation of control algorithms to batch bioreactors is often complicated by the inherent variations in process dynamics during the course of fermentation. Such a wide operating range may render the performance of fixed gain PID controllers unsatisfactory. In this work, a detailed study on the control of batch fermentation is performed. Furthermore, a simple batch controller design is proposed which incorporates the concept of gain-scheduling, a subclass of adaptive control, with oxygen uptake rate as an auxiliary variable. The control of oxygen tension in the biorector is used as a vehicle to convey the proposed idea, analysis and results. Simulation experiments indicate significant improvement in controller performance can be achieved by the proposed approach even in the presence of measurement noise.

  17. Batch variation between branchial cell cultures: An analysis of variance

    Hansen, Heinz Johs. Max; Grosell, M.; Kristensen, L.

    2003-01-01

    We present in detail how a statistical analysis of variance (ANOVA) is used to sort out the effect of an unexpected batch-to-batch variation between cell cultures. Two separate cultures of rainbow trout branchial cells were grown on permeable filtersupports ("inserts"). They were supposed...... and introducing the observed difference between batches as one of the factors in an expanded three-dimensional ANOVA, we were able to overcome an otherwisecrucial lack of sufficiently reproducible duplicate values. We could thereby show that the effect of changing the apical medium was much more marked when...... the radioactive lipid precursors were added on the apical, rather than on the basolateral, side. Theinsert cell cultures were obviously polarized. We argue that it is not reasonable to reject troublesome experimental results, when we do not know a priori that something went wrong. The ANOVA is a very useful...

  18. From Fed-batch to Continuous Enzymatic Biodiesel Production

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John M.

    2015-01-01

    In this this paper, we use mechanistic modelling to guide the development of acontinuous enzymatic process that is performed as a fed-batch operation. In this workwe use the enzymatic biodiesel process as a case study. A mechanistic model developedin our previous work was used to determine...... measured components (triglycerides, diglycerides, monoglycerides, free fatty acid and fatty acid methyl esters(biodiesel)) much better than using fed-batch data alone given the smaller residuals. We also observe a reduction in the correlation between the parameters.The model was then used to predict that 5...... reactors are required (with a combined residence time of 30 hours) to reach a final biodiesel concentration within 2 % of the95.6 mass % achieved in a fed-batch operation, for 24 hours....

  19. Continuous flow technology vs. the batch-by-batch approach to produce pharmaceutical compounds.

    Cole, Kevin P; Johnson, Martin D

    2018-01-01

    For the manufacture of small molecule drugs, many pharmaceutical innovator companies have recently invested in continuous processing, which can offer significant technical and economic advantages over traditional batch methodology. This Expert Review will describe the reasons for this interest as well as many considerations and challenges that exist today concerning continuous manufacturing. Areas covered: Continuous processing is defined and many reasons for its adoption are described. The current state of continuous drug substance manufacturing within the pharmaceutical industry is summarized. Current key challenges to implementation of continuous manufacturing are highlighted, and an outlook provided regarding the prospects for continuous within the industry. Expert commentary: Continuous processing at Lilly has been a journey that started with the need for increased safety and capability. Over twelve years the original small, dedicated group has grown to more than 100 Lilly employees in discovery, development, quality, manufacturing, and regulatory designing in continuous drug substance processing. Recently we have focused on linked continuous unit operations for the purpose of all-at-once pharmaceutical manufacturing, but the technical and business drivers that existed in the very beginning for stand-alone continuous unit operations in hybrid processes have persisted, which merits investment in both approaches.

  20. A High-Fidelity Batch Simulation Environment for Integrated Batch and Piloted Air Combat Simulation Analysis

    Goodrich, Kenneth H.; McManus, John W.; Chappell, Alan R.

    1992-01-01

    A batch air combat simulation environment known as the Tactical Maneuvering Simulator (TMS) is presented. The TMS serves as a tool for developing and evaluating tactical maneuvering logics. The environment can also be used to evaluate the tactical implications of perturbations to aircraft performance or supporting systems. The TMS is capable of simulating air combat between any number of engagement participants, with practical limits imposed by computer memory and processing power. Aircraft are modeled using equations of motion, control laws, aerodynamics and propulsive characteristics equivalent to those used in high-fidelity piloted simulation. Databases representative of a modern high-performance aircraft with and without thrust-vectoring capability are included. To simplify the task of developing and implementing maneuvering logics in the TMS, an outer-loop control system known as the Tactical Autopilot (TA) is implemented in the aircraft simulation model. The TA converts guidance commands issued by computerized maneuvering logics in the form of desired angle-of-attack and wind axis-bank angle into inputs to the inner-loop control augmentation system of the aircraft. This report describes the capabilities and operation of the TMS.

  1. Optimized Synthesis of Foam Glass from Recycled CRT Panel Glass

    Petersen, Rasmus Rosenlund; König, Jakob; Yue, Yuanzheng

    Most of the panel glass from cathode ray tubes (CRTs) is landfilled today. Instead of landfilling, the panel glass can be turned into new environment-friendly foam glass. Low density foam glass is an effective heat insulating material and can be produced just by using recycle glass and foaming...... additives. In this work we recycle the CRT panel glass to synthesize the foam glass as a crucial component of building and insulating materials. The synthesis conditions such as foaming temperature, duration, glass particle size, type and concentrations of foaming agents, and so on are optimized...... by performing systematic experiments. In particular, the concentration of foaming agents is an important parameter that influences the size of bubbles and the distribution of bubbles throughout the sample. The foam glasses are characterised regarding density and open/closed porosity. Differential scanning...

  2. Production of tea vinegar by batch and semicontinuous fermentation

    Kaur, Pardeep; Kocher, G. S.; Phutela, R. P.

    2010-01-01

    The fermented tea vinegar combines the beneficial properties of tea and vinegar. The complete fermentation takes 4 to 5 weeks in a batch culture and thus can be shortened by semi continuous/ continuous fermentation using immobilized bacterial cells. In the present study, alcoholic fermentation of 1.0 and 1.5% tea infusions using Saccharomyces cerevisae G was carried out that resulted in 84.3 and 84.8% fermentation efficiency (FE) respectively. The batch vinegar fermentation of these wines wit...

  3. Stochastic growth logistic model with aftereffect for batch fermentation process

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-06-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  4. Stochastic growth logistic model with aftereffect for batch fermentation process

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-01-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits

  5. Stochastic growth logistic model with aftereffect for batch fermentation process

    Rosli, Norhayati; Ayoubi, Tawfiqullah [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Pahang (Malaysia); Bahar, Arifah; Rahman, Haliza Abdul [Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Salleh, Madihah Md [Department of Biotechnology Industry, Faculty of Biosciences and Bioengineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

    2014-06-19

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  6. Optimum heat storage design for heat integrated multipurpose batch plants

    Stamp, J

    2011-01-01

    Full Text Available procedure is presented tha journal homepage: www All rights reserved. ajozi T, Optimum heat storage grated multipurpose batch plants , South Africa y usage in multipurpose batch plants has been in published literature most present methods, time... � 2pL?u?kins ? 1 h3A3?u?cu?U (36) The internal area for heat loss by convection from the heat transfer medium is given by Constraint (37) and the area for convective heat transfer losses to the environment is given in Constraint (38). A1?u? ? 2...

  7. An Assessment of the Sulfate Solubility Limit for the FRIT 418 - Sludge Batch 2/3 System

    PEELER, D.K.

    2004-01-01

    The objective of this report is to establish a ''single point'' sulfate solubility limit or constraint for the Frit 418 - Sludge Batch 2/3 (SB2/3) system. Based on the results of this study, it is recommended that the glass limit in the Product Composition Control System (PCCS) for the Frit 418 - SB2/3 system be set at 0.60 wt%. The new limit has been set based solely on sealed crucible scale data and does not take credit or account for potential volatilization that may occur in the Defense Waste Processing Facility (DWPF) melter. Although the limit is established based on sealed crucible scale tests, supplementary testing using the Slurry-Fed Melt Rate Furnace (SMRF) provides a measure of confidence that applying the 0.6 wt% limit in PCCS will prevent the formation of a salt layer in the melter. The critical data point that was used to define the solubility limit for this system was from a ''spiked'' 30% waste loading (WL) glass targeting 0.65 wt%. The measured content in this glass was 0.62 wt%. Applying the Savannah River Technology Center - Mobile Laboratory (SRTCML) inductively coupled plasma (ICP) atomic emission spectroscopy (AES) uncertainties to establish a solubility limit for the Frit 418 - SB2/3 system of 0.60 wt% (in glass) provides a ''single point'' limit that covers the anticipated WL interval of interest. It is noted that there are glasses above the 0.60 wt% limit that were homogeneous, thus reinforcing the theory of a compositional effect on solubility within this specific system. In general, higher solubilities were observed at higher targeted waste loadings

  8. Calibration and Measurement of the Viscosity of DWPF Start-Up Glass

    Schumacher, R.F.

    2001-01-01

    The Harrop, High-Temperature Viscometer has been in operation at the Savannah River Technology Center (SRTC) for several years and has proven itself to be reasonably accurate and repeatable. This is particularly notable when taking into consideration the small amount of glass required to make the viscosity determination. The volume of glass required is only 2.60 cc or about 6 to 7 grams of glass depending on the glass density. This may be compared to the more traditional viscosity determinations, which generally require between 100 to 1000 grams of glass. Before starting the present investigation, the unit was re-aligned and the furnace thermal gradients measured. The viscometer was again calibrated with available NIST Standard Reference Material glasses (717a and 710a) and a spindle constant equation was determined. Standard DWPF Waste Compliance Glasses (Purex, HM, and Batch 1) were used to provide additional verification for the determinations at low temperature. The Harrop, High-Temperature Viscometer was then used to determine the viscosity of three random samples of ground and blended DWPF, Black, Start -Up Frit, which were obtained from Pacific Northwest National Laboratory (PNNL). The glasses were in powder form and required melting prior to the viscosity determination. The results from this evaluation will be compared to ''Round Robin'' measurements from other DOE laboratories and a number of commercial laboratories

  9. IMPACTS OF SMALL COLUMN ION EXCHANGE STREAMS ON DWPF GLASS FORMULATION: KT01, KT02, KT03, AND KT04-SERIES GLASS COMPOSITIONS

    Fox, K.; Edwards, T.

    2010-11-01

    Four series of glass compositions were selected, fabricated, and characterized as part of a study to determine the impacts of the addition of Crystalline Silicotitanate (CST) and Monosodium Titanate (MST) from the Small Column Ion Exchange (SCIX) process on the Defense Waste Processing Facility (DWPF) glass waste form and the applicability of the DWPF process control models. The KT01 and KT02-series of glasses were chosen to allow for the identification of the influence of the concentrations of major components of the glass on the retention of TiO{sub 2}. The KT03 series of glasses was chosen to allow for the identification of these influences when higher Nb{sub 2}O{sub 5} and ZrO{sub 2} concentrations are included along with TiO2. The KT04 series of glasses was chosen to investigate the properties and performance of glasses based on the best available projections of actual compositions to be processed at the DWPF (i.e., future sludge batches including the SCIX streams).

  10. Nuclear waste glass corrosion mechanisms

    Jantzen, C.M.

    1987-04-01

    Dissolution of nuclear waste glass occurs by corrosion mechanisms similar to those of other solids, e.g., metallurgical and mineralogic systems. Metallurgical phenomena such as active corrosion, passivation and immunity have been observed to be a function of the glass composition and the solution pH. Hydration thermodynamics was used to quantify the role of glass composition and its effect on the solution pH during dissolution. A wide compositional range of natural, lunar, medieval, and nuclear waste glasses, as well as some glass-ceramics were investigated. The factors observed to affect dissolution in deionized water are pertinent to the dissolution of glass in natural environments such as the groundwaters anticipated to interact with nuclear waste glass in a geologic repository. The effects of imposed pH and oxidation potential (Eh) conditions existing in natural environments on glass dissolution is described in the context of Pourbaix diagrams, pH potential diagrams, for glass

  11. Electrical properties of phosphate glasses

    Mogus-Milankovic, A; Santic, A; Reis, S T; Day, D E

    2009-01-01

    Investigation of the electrical properties of phosphate glasses where transition metal oxide such as iron oxide is the network former and network modifier is presented. Phosphate glasses containing iron are electronically conducting glasses where the polaronic conduction is due to the electron hopping from low to high iron valence state. The identification of structural defects caused by ion/polaron migration, the analysis of dipolar states and electrical conductivity in iron phosphate glasses containing various alkali and mixed alkali ions was performed on the basis of the impedance spectroscopy (IS). The changes in electrical conductivity from as-quenched phosphate glass to fully crystallized glass (glass-ceramics) by IS are analyzed. A change in the characteristic features of IS follows the changes in glass and crystallized glass network. Using IS, the contribution of glass matrix, crystallized grains and grain boundary to the total electrical conductivity for iron phosphate glasses was analyzed. It was shown that decrease in conductivity is caused by discontinuities in the conduction pathways as a result of the disruption of crystalline network where two or more crystalline phases are formed. Also, phosphate-based glasses offer a unique range of biomaterials, as they form direct chemical bonding with hard/soft tissue. The surface charges of bioactive glasses are recognized to be the most important factors in determining biological responses. The improved bioactivity of the bioactive glasses as a result of the effects of the surface charges generated by electrical polarization is discussed.

  12. Theory of glass

    Rivier, N.

    1985-01-01

    The physical properties of glass are direct consequences of its non-crystalline structure. The structure is described from a topological point of view, since topology is the only geometry surviving non-crystallinity, i.e. absence of metric and trivial space group. This fact has two main consequences: the overall homogeneity of glass is a gauge symmetry, and the only extended, structurally stable constituents are odd lines (or 2π-disclinations in the elastic continuum limit). A gauge theory of glass, based on odd lines as sources of frozen-in strain, can explain those properties of glasses which are both specific to, and universal in amorphous solids: low-temperature excitations, and relaxation at high temperatures. The methods of statistical mechanics can be applied to give a minimal description of amorphous structures in statistical equilibrium. Criteria for statistical equilibrium of the structure and detailed balance are given, together with structural equations of state, which turn out to be well-known empirically among botanists and metallurgists. This review is based on lectures given in 1984 in Niteroi. It contains five parts: I - Structure, from a topological viewpoint; II - gauge invariance; III - Tunneling modes; IV - Supercooled liquid and the glass transitions; V - Statistical crystallography. (Author) [pt

  13. Design of two-column batch-to-batch recirculation to enhance performance in ion-exchange chromatography.

    Persson, Oliver; Andersson, Niklas; Nilsson, Bernt

    2018-01-05

    Preparative liquid chromatography is a separation technique widely used in the manufacturing of fine chemicals and pharmaceuticals. A major drawback of traditional single-column batch chromatography step is the trade-off between product purity and process performance. Recirculation of impure product can be utilized to make the trade-off more favorable. The aim of the present study was to investigate the usage of a two-column batch-to-batch recirculation process step to increase the performance compared to single-column batch chromatography at a high purity requirement. The separation of a ternary protein mixture on ion-exchange chromatography columns was used to evaluate the proposed process. The investigation used modelling and simulation of the process step, experimental validation and optimization of the simulated process. In the presented case the yield increases from 45.4% to 93.6% and the productivity increases 3.4 times compared to the performance of a batch run for a nominal case. A rapid concentration build-up product can be seen during the first cycles, before the process reaches a cyclic steady-state with reoccurring concentration profiles. The optimization of the simulation model predicts that the recirculated salt can be used as a flying start of the elution, which would enhance the process performance. The proposed process is more complex than a batch process, but may improve the separation performance, especially while operating at cyclic steady-state. The recirculation of impure fractions reduces the product losses and ensures separation of product to a high degree of purity. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates

    Wiebe Marilyn G

    2012-05-01

    Full Text Available Abstract Background Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. Methods R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100 media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Results Lipid production was most efficient with glucose (up to 25 g lipid L−1, 48 to 75% lipid in the biomass, at up to 0.21 g lipid L−1 h−1 as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass. Lipid production was low (15–19% lipid in biomass with arabinose as sole carbon source and was lower than expected (30% lipid in biomass when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L−1, with 49% lipid in the biomass and fed-batch (35 to 47 g L−1, with 50 to 75% lipid in the biomass cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Conclusions Lipid production in R. toruloides was lower from arabinose and mixed

  15. Kinetic effects in the conversion of fast waves in pre-heated, low aspect ratio tokamak plasmas

    Kommoshvili, K [School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv (Israel); Cuperman, S [School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv (Israel); Bruma, C [School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv (Israel)

    2003-03-01

    Kinetic effects in the conversion of fast waves to Alfven waves and their subsequent deposition in low aspect ratio (spherical) tokamaks (LARTs) have been investigated theoretically. More specifically, we have considered the consequences of incorporation of kinetic effects in the electron parallel (to the ambient magnetic field) dynamics derived by following the drift-tearing mode analysis of Chen et al (Chen L, Rutherford P H and Tang W M 1977 Phys. Rev. Lett. 39 460), and particle-conserving Krook collision operator for the passing electrons involved (Mett R R and Mahajan S M 1992 Phys. Fluids B 4 2885). The perpendicular plasma dynamics is described by a quite general resistive two-fluid (2F) model based dielectric tensor-operator (Cuperman S, Bruma C and Komoshvili K 2002 Solution of the resistive 2F wave equations for Alfvenic modes in spherical tokamak plasmas J. Plasma Phys. accepted for publication). The full-wave electromagnetic equations, formulated in terms of the vector and scalar potentials, have been solved by the aid of an advanced finite elements numerical code (Sewell G 1993 Adv. Eng. Software 17 105). Detailed solutions of the full-wave equations are obtained and compared with those corresponding to a pure resistive 2F model, this, for the illustrative pre-heated START-type device (Sykes 1994). Our results quantitatively confirm the general theory of the conversion of fast waves with subsequent power dissipation for the conditions of spherical tokamaks thus providing the required auxiliary energy source for the successful operation of LARTs. Moreover, these results indicate the absolute necessity of using a full model for the parallel electron dynamics, i.e. including both kinetic and collisional effects.

  16. Kinetic effects in the conversion of fast waves in pre-heated, low aspect ratio tokamak plasmas

    Kommoshvili, K; Cuperman, S; Bruma, C

    2003-01-01

    Kinetic effects in the conversion of fast waves to Alfven waves and their subsequent deposition in low aspect ratio (spherical) tokamaks (LARTs) have been investigated theoretically. More specifically, we have considered the consequences of incorporation of kinetic effects in the electron parallel (to the ambient magnetic field) dynamics derived by following the drift-tearing mode analysis of Chen et al (Chen L, Rutherford P H and Tang W M 1977 Phys. Rev. Lett. 39 460), and particle-conserving Krook collision operator for the passing electrons involved (Mett R R and Mahajan S M 1992 Phys. Fluids B 4 2885). The perpendicular plasma dynamics is described by a quite general resistive two-fluid (2F) model based dielectric tensor-operator (Cuperman S, Bruma C and Komoshvili K 2002 Solution of the resistive 2F wave equations for Alfvenic modes in spherical tokamak plasmas J. Plasma Phys. accepted for publication). The full-wave electromagnetic equations, formulated in terms of the vector and scalar potentials, have been solved by the aid of an advanced finite elements numerical code (Sewell G 1993 Adv. Eng. Software 17 105). Detailed solutions of the full-wave equations are obtained and compared with those corresponding to a pure resistive 2F model, this, for the illustrative pre-heated START-type device (Sykes 1994). Our results quantitatively confirm the general theory of the conversion of fast waves with subsequent power dissipation for the conditions of spherical tokamaks thus providing the required auxiliary energy source for the successful operation of LARTs. Moreover, these results indicate the absolute necessity of using a full model for the parallel electron dynamics, i.e. including both kinetic and collisional effects

  17. Kinetic effects in the conversion of fast waves in pre-heated, low aspect ratio tokamak plasmas

    Kommoshvili, K.; Cuperman, S.; Bruma, C.

    2003-03-01

    Kinetic effects in the conversion of fast waves to Alfvèn waves and their subsequent deposition in low aspect ratio (spherical) tokamaks (LARTs) have been investigated theoretically. More specifically, we have considered the consequences of incorporation of kinetic effects in the electron parallel (to the ambient magnetic field) dynamics derived by following the drift-tearing mode analysis of Chen et al (Chen L, Rutherford P H and Tang W M 1977 Phys. Rev. Lett. 39 460), and particle-conserving Krook collision operator for the passing electrons involved (Mett R R and Mahajan S M 1992 Phys. Fluids B 4 2885). The perpendicular plasma dynamics is described by a quite general resistive two-fluid (2F) model based dielectric tensor-operator (Cuperman S, Bruma C and Komoshvili K 2002 Solution of the resistive 2F wave equations for Alfvènic modes in spherical tokamak plasmas J. Plasma Phys. accepted for publication). The full-wave electromagnetic equations, formulated in terms of the vector and scalar potentials, have been solved by the aid of an advanced finite elements numerical code (Sewell G 1993 Adv. Eng. Software 17 105). Detailed solutions of the full-wave equations are obtained and compared with those corresponding to a pure resistive 2F model, this, for the illustrative pre-heated START-type device (Sykes 1994). Our results quantitatively confirm the general theory of the conversion of fast waves with subsequent power dissipation for the conditions of spherical tokamaks thus providing the required auxilliary energy source for the succesful operation of LARTs. Moreover, these results indicate the absolute necessity of using a full model for the parallel electron dynamics, i.e. including both kinetic and collisional effects.

  18. Impact of preheating on the behavior of Listeria monocytogenes in a broth that mimics Camembert cheese composition.

    Helloin, E; Bouttefroy, A; Gay, M; Phan Thanh, L

    2003-02-01

    The effect of preheating on the survival of L. monocytogenes in Richard's broth, which mimics the composition of Camembert cheese composition, was examined. Experiments were carried out to reproduce contamination of cheese with environmental heat-stressed cells of L. monocytogenes surviving hot-cleaning procedures. Cells in mid-log phase were heated for 30 min at 56 degrees C before being inoculated into Richard's broth. The pHs and temperatures of Richard's broth were chosen to recreate the conditions of curd dripping (pH 5, 25 degrees C), of the beginning of cheese ripening (pH 5, 12 degrees C), and of the beginning (pH 5, 4 degrees C) and the end (pH 7, 4 degrees C) of cheese storage. Immediately after heat treatment, the viability loss was especially high for strain 306715, which exhibited only 0.6% +/- 0.2% survival, compared with 22% +/- 8.7% for strain EGD. The percentages of the surviving heated cells that were injured were 93% +/- 8% for strain 306715 and 98% +/- 3% for strain EGD. The destruction of the surviving L. monocytogenes cells was accelerated when they encountered the pH and temperature conditions of Camembert cheese during manufacturing, ripening, and cold storage (pH 5 at 25, 12, and 4 degrees C, respectively). The multiplication of the surviving heated cells was retarded under favorable growth conditions similar to those of storage by the distributor and the consumer (pH 7 at 4 and 12 degrees C, respectively).

  19. Ion exchange for glass strengthening

    Gy, Rene

    2008-01-01

    This paper presents a short overview of silicate glass strengthening by exchange of alkali ions in a molten salt, below the glass transition temperature (chemical tempering). The physics of alkali inter-diffusion is briefly explained and the main parameters of the process, which control the glass reinforcement, are reviewed. Methods for characterizing the obtained residual stress state and the strengthening are described, along with the simplified modelling of the stress build-up. The fragmentation of chemically tempered glass is discussed. The concept of engineered stress profile glass is presented, and finally, the effect of glass and salt compositions is overviewed

  20. SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 7A QUALIFICATION

    Pareizs, J.; Billings, A.; Click, D.

    2011-07-08

    Waste Solidification Engineering (WSE) has requested that characterization and a radioactive demonstration of the next batch of sludge slurry (Sludge Batch 7a*) be completed in the Shielded Cells Facility of the Savannah River National Laboratory (SRNL) via a Technical Task Request (TTR). This characterization and demonstration, or sludge batch qualification process, is required prior to transfer of the sludge from Tank 51 to the Defense Waste Processing Facility (DWPF) feed tank (Tank 40). The current WSE practice is to prepare sludge batches in Tank 51 by transferring sludge from other tanks. Discharges of nuclear materials from H Canyon are often added to Tank 51 during sludge batch preparation. The sludge is washed and transferred to Tank 40, the current DWPF feed tank. Prior to transfer of Tank 51 to Tank 40, SRNL simulates the Tank Farm and DWPF processes with a Tank 51 sample (referred to as the qualification sample). Sludge Batch 7a (SB7a) is composed of portions of Tanks 4, 7, and 12; the Sludge Batch 6 heel in Tank 51; and a plutonium stream from H Canyon. SRNL received the Tank 51 qualification sample (sample ID HTF-51-10-125) following sludge additions to Tank 51. This report documents: (1) The washing (addition of water to dilute the sludge supernate) and concentration (decanting of supernate) of the SB7a - Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF Chemical Process Cell (CPC) simulation using the washed Tank 51 sample. The simulation included a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid was added to the sludge to destroy nitrite and reduce mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit was added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters were based on work with a non

  1. Spectrophotometric study of bio-sorption of uranium on glass grade spodumene shell powder

    Parakudyil, A.S.; Pillai, A.K.; Reddy, A.V.R.; Singal, R.K.; Sharma, P.K.; Michael, K.M.

    2012-01-01

    Separation of uranium found in iron ore leachates was done by extraction chromatography using glass grade spodumene shellpowder (GSS) in nitric acid medium and analyzed spectrophotometrically. The influences of metal ion concentration, pH and adsorption capacity of biomass were investigated. Biosorption is a potential method of separation of heavy and trace metals from waste water and effluents from various sources. The adsorption capacities of biomass were investigated by batch experiments and column experiments. In the present study, glass grade spodumene shell powder (GSS) in acidic medium is being used as a biosorbent

  2. Sludge Washing and Demonstration of the DWPF Nitric/Formic Flowsheet in the SRNL Shielded Cells for Sludge Batch 9 Qualification

    Pareizs, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Newell, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Martino, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Johnson, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-11-01

    Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) to qualify the next batch of sludge – Sludge Batch 9 (SB9). Current practice is to prepare sludge batches in Tank 51 by transferring sludge to Tank 51 from other tanks. The sludge is washed and transferred to Tank 40, the current Defense Waste Process Facility (DWPF) feed tank. Prior to sludge transfer from Tank 51 to Tank 40, the Tank 51 sludge must be qualified. SRNL qualifies the sludge in multiple steps. First, a Tank 51 sample is received, then characterized, washed, and again characterized. SRNL then demonstrates the DWPF Chemical Process Cell (CPC) flowsheet with the sludge. The final step of qualification involves chemical durability measurements of glass fabricated in the DWPF CPC demonstrations. In past sludge batches, SRNL had completed the DWPF demonstration with Tank 51 sludge. For SB9, SRNL has been requested to process a blend of Tank 51 and Tank 40 at a targeted ratio of 44% Tank 51 and 56% Tank 40 on an insoluble solids basis.

  3. Perspectives on spin glasses

    Contucci, Pierluigi

    2013-01-01

    Presenting and developing the theory of spin glasses as a prototype for complex systems, this book is a rigorous and up-to-date introduction to their properties. The book combines a mathematical description with a physical insight of spin glass models. Topics covered include the physical origins of those models and their treatment with replica theory; mathematical properties like correlation inequalities and their use in the thermodynamic limit theory; main exact solutions of the mean field models and their probabilistic structures; and the theory of the structural properties of the spin glass phase such as stochastic stability and the overlap identities. Finally, a detailed account is given of the recent numerical simulation results and properties, including overlap equivalence, ultrametricity and decay of correlations. The book is ideal for mathematical physicists and probabilists working in disordered systems.

  4. Waste glass melting stages

    Anderson, L.D.; Dennis, T.; Elliott, M.L.; Hrma, P.

    1994-01-01

    Three simulated nuclear waste glass feeds, consisting of dried waste and glass frit, were heat treated for 1 hour in a gradient furnace at temperatures ranging from approximately 600 degrees C to 1000 degrees C. Simulated melter feeds from the Hanford Waste Vitrification Plant (HWVP), the Defense Waste Processing Facility (DWPF), and Kernforschungszentru Karlsruhe (KfK) in Germany were used. The samples were thin sectioned and examined by optical microscopy to investigate the stages of the conversion from feed to glass. Various phenomena were seen, such as frit softening, bubble formation, foaming, bubble motion and removal, convective mixing, and homogenization. The behavior of different feeds was similar, although the degree of gas generation and melt homogenization varied. 2 refs., 8 tabs

  5. Waste glass melting stages

    Anderson, L.D.; Dennis, T.; Elliott, M.L.; Hrma, P.

    1993-04-01

    Three different simulated nuclear waste glass feeds, consisting of dried waste and glass frit, were heat treated for 1 hour in a gradient furnace at temperatures ranging from approximately 600 degrees C--1000 degrees C. Simulated melter feeds from the Hanford Waste Vitrification Plant (HWVP), the Defense Waste Processing Facility (DWPF), and Kernforschungszentrum Karlsruhe (KfK) in Germany were used. The samples were thin-sectioned and examined by optical microscopy to investigate the stages of the conversion from feed to glass. Various phenomena were seen, such as frit softening, bubble formation, foaming, bubble motion and removal, convective mixing, and homogenization. Behavior of different feeds was similar, although the degree of gas generation and melt homogenization varied

  6. Investigation of Rheological Impacts on Sludge Batch 3 as Insoluble Solids and Wash Endpoints are Adjusted

    Fellinger, T. L.

    2005-01-01

    The Defense Waste Processing Facility (DWPF) is currently processing and immobilizing radioactive sludge slurry into a durable borosilicate glass. The DWPF has already processed three sludge batches (Sludge Batch 1A, Sludge Batch 1B, and Sludge Batch 2) and is currently processing the fourth sludge batch (Sludge Batch 3). A sludge batch is defined as a single tank of sludge slurry or a combination of sludge slurries from different tanks that has been or will be qualified before being transferred to DWPF. As a part of the Sludge Batch 3 (SB3) qualification task, rheology measurements of the sludge slurry were requested at different insoluble solids loadings. These measurements were requested in order to gain insight into potential processing problems that may occur as the insoluble solids are adjusted up or down (by concentration or dilution) during the process. As a part of this study, a portion of the ''as received'' SB3 sample was washed with inhibited water (0.015 M NaOH and 0.015 M NaNO2) to target 0.5M Na versus a measured 1M Na in the supernate. The purpose of the ''washing'' step was to allow a comparison of the SB3 rheological data to the rheological data collected for Sludge Batch 2 (SB2) and to determine if there was a dependence of the yield stress and consistency as a function of washing. The ''as received'' SB3 rheology data was also compared to SB3 simulants prepared by the Simulant Development Program in order to provide guidance for selecting a simulant that is more representative of the rheological properties of the radioactive sludge slurry. A summary of the observations, conclusions are: (1) The yield stress and plastic viscosity increased as the weight percent insoluble solids were increased for the ''as received'' and ''washed'' SB3 samples, at a fixed pH. (2) For the same insoluble solids loading, the yield stress for the SB2 sample is approximately a factor of three higher than the ''as received'' SB3 sample. There also appears to be small

  7. Adaptation to high throughput batch chromatography enhances multivariate screening.

    Barker, Gregory A; Calzada, Joseph; Herzer, Sibylle; Rieble, Siegfried

    2015-09-01

    High throughput process development offers unique approaches to explore complex process design spaces with relatively low material consumption. Batch chromatography is one technique that can be used to screen chromatographic conditions in a 96-well plate. Typical batch chromatography workflows examine variations in buffer conditions or comparison of multiple resins in a given process, as opposed to the assessment of protein loading conditions in combination with other factors. A modification to the batch chromatography paradigm is described here where experimental planning, programming, and a staggered loading approach increase the multivariate space that can be explored with a liquid handling system. The iterative batch chromatography (IBC) approach is described, which treats every well in a 96-well plate as an individual experiment, wherein protein loading conditions can be varied alongside other factors such as wash and elution buffer conditions. As all of these factors are explored in the same experiment, the interactions between them are characterized and the number of follow-up confirmatory experiments is reduced. This in turn improves statistical power and throughput. Two examples of the IBC method are shown and the impact of the load conditions are assessed in combination with the other factors explored. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Control of polymer network topology in semi-batch systems

    Wang, Rui; Olsen, Bradley; Johnson, Jeremiah

    Polymer networks invariably possess topological defects: loops of different orders. Since small loops (primary loops and secondary loops) both lower the modulus of network and lead to stress concentration that causes material failure at low deformation, it is desirable to greatly reduce the loop fraction. We have shown that achieving loop fraction close to zero is extremely difficult in the batch process due to the slow decay of loop fraction with the polymer concentration and chain length. Here, we develop a modified kinetic graph theory that can model network formation reactions in semi-batch systems. We demonstrate that the loop fraction is not sensitive to the feeding policy if the reaction volume maintains constant during the network formation. However, if we initially put concentrated solution of small junction molecules in the reactor and continuously adding polymer solutions, the fractions of both primary loop and higher-order loops will be significantly reduced. There is a limiting value (nonzero) of loop fraction that can be achieved in the semi-batch system in condition of extremely slow feeding rate. This minimum loop fraction only depends on a single dimensionless variable, the product of concentration and with single chain pervaded volume, and defines an operating zone in which the loop fraction of polymer networks can be controlled through adjusting the feeding rate of the semi-batch process.

  9. State and parameter estimation in biotechnical batch reactors

    Keesman, K.J.

    2000-01-01

    In this paper the problem of state and parameter estimation in biotechnical batch reactors is considered. Models describing the biotechnical process behaviour are usually nonlinear with time-varying parameters. Hence, the resulting large dimensions of the augmented state vector, roughly > 7, in

  10. Batch distillation column modeling for quality control program

    Betlem, Bernardus H.L.

    2000-01-01

    For batch distillation, the dynamic composition behaviour can be described by the dominant time constant and the bottom exhaustion. Its magnitude is determined by the change of the composition distribution and is maximal when the inflection point of the molar fraction profile is located in the

  11. Sequencing for Batch Production in a Group Flowline Machine Shop ...

    The purpose of the paper is to develop a useful technique for sequencing batches of components through machine shops arranged under the group flowline production system. The approach is to apply a modified version of Petrov's group flowline technique for machining components which follow a unidirectional route.

  12. Quality control for 12 batch of DTPA-Sn

    Isaac, M.; Gamboa, R.; Leyva, R.; Hernandez, I.; Turino, D.

    1994-01-01

    The quality control is carry out at 12 batch of DTPA-Sn for labeling with 99 m Tc. The instrumental methods of analysis and control charts were discussed in order to find a warranty time for the product. (author). 2 refs, 3 figs, 1 tab

  13. Flash chemistry: flow chemistry that cannot be done in batch.

    Yoshida, Jun-ichi; Takahashi, Yusuke; Nagaki, Aiichiro

    2013-11-04

    Flash chemistry based on high-resolution reaction time control using flow microreactors enables chemical reactions that cannot be done in batch and serves as a powerful tool for laboratory synthesis of organic compounds and for production in chemical and pharmaceutical industries.

  14. Adsorption of Arsenite onto Kemiron in a batch system

    doti

    This study investigated the effect of pH and coexisting ions on As(III) adsorption using batch experiment and discovered that pH strongly influenced As(III) adsorption. However, differences ... contamination by such heavy metals as arsenic (As). Arsenite ..... and then transition through point of zero charge (PZC) and then into ...

  15. Development of Production Control in Small Batch Production

    Németh Péter

    2016-01-01

    Full Text Available Our aim with this paper is to develop a new performance measurement and control system for small batch production in the automotive industry. For this reason, we present our previous research results for warehouse performance measurement and adopt its methodology to production control. The proposed method is based on artificial intelligence (neural networks.

  16. Shell of Planet Earth – Global Batch Bioreactor.

    Hanika, Jiří; Šolcová, Olga; Kaštánek, P.

    2017-01-01

    Roč. 40, č. 11 (2017), s. 1959-1965 ISSN 0930-7516 R&D Projects: GA TA ČR TE01020080 Institutional support: RVO:67985858 Keywords : critical raw materials * global batch bioreactor * planet earth Subject RIV: CI - Industrial Chemistry, Chemical Engineering OBOR OECD: Chemical process engineering Impact factor: 2.051, year: 2016

  17. Design of common heat exchanger network for batch processes

    Anastasovski, Aleksandar

    2014-01-01

    Heat integration of energy streams is very important for the efficient energy recovery in production systems. Pinch technology is a very useful tool for heat integration and maximizing energy efficiency. Creating of heat exchangers network as a common solution for systems in batch mode that will be applicable in all existing time slices is very difficult. This paper suggests a new methodology for design of common heat exchanger network for batch processes. Heat exchanger network designs were created for all determined repeatable and non-repeatable time periods – time slices. They are the basis for creating the common heat exchanger network. The common heat exchanger network as solution, satisfies all heat-transfer needs for each time period and for every existing combination of selected streams in the production process. This methodology use split of some heat exchangers into two or more heat exchange units or heat exchange zones. The reason for that is the multipurpose use of heat exchangers between different pairs of streams in different time periods. Splitting of large heat exchangers would maximize the total heat transfer usage of heat exchange units. Final solution contains heat exchangers with the minimum heat load as well as the minimum need of heat transfer area. The solution is applicable for all determined time periods and all existing stream combinations. - Highlights: •Methodology for design of energy efficient systems in batch processes. •Common Heat Exchanger Network solution based on designs with Pinch technology. •Multipurpose use of heat exchangers in batch processes

  18. A fixed-size batch service queue with vacations

    Ho Woo Lee

    1996-01-01

    Full Text Available The paper deals with batch service queues with vacations in which customers arrive according to a Poisson process. Decomposition method is used to derive the queue length distributions both for single and multiple vacation cases. The authors look at other decomposition techniques and discuss some related open problems.

  19. Comparative Batch and Column Evaluation of Thermal and Wet ...

    The efficiency of regenerated spent commercial activated carbon for synthetic dye removal was studied using thermal and wet oxidative regeneration methods. Two types of experiments were carried out, batch adsorption experiments and continous flow (fixed bed) column experiment to study the mechanism of dye removal ...

  20. DEVELOPMENT OF AN AUTOMATED BATCH-PROCESS SOLAR ...

    One of the shortcomings of solar disinfection of water (SODIS) is the absence of a feedback mechanism indicating treatment completion. This work presents the development of an automated batch-process water disinfection system aimed at solving this challenge. Locally sourced materials in addition to an Arduinomicro ...

  1. Medium optimization for protopectinase production by batch culture of

    Medium optimization for protopectinase production by batch culture of. C Fan, Z Liu, L Yao. Abstract. Optimization of medium compositions for protopectinase production by Aspergillus terreus in submerged culture was carried out. The medium components having significant effect on protopectinase production were reported ...

  2. Batch immunoextraction method for efficient purification of aromatic cytokinins

    Hauserová, Eva; Swaczynová, Jana; Doležal, Karel; Lenobel, René; Popa, Igor; Hajdúch, M.; Vydra, D.; Fuksová, Květoslava; Strnad, Miroslav

    2005-01-01

    Roč. 1100, č. 1 (2005), s. 116-125 ISSN 0021-9673 R&D Projects: GA AV ČR IBS4055304 Institutional research plan: CEZ:AV0Z50380511; MSM6198959216 Keywords : antibody * 6-benzylaminopurine * batch immunoextraction Subject RIV: ED - Physiology Impact factor: 3.096, year: 2005

  3. Tier 3 batch system data locality via managed caches

    Fischer, Max; Giffels, Manuel; Jung, Christopher; Kühn, Eileen; Quast, Günter

    2015-05-01

    Modern data processing increasingly relies on data locality for performance and scalability, whereas the common HEP approaches aim for uniform resource pools with minimal locality, recently even across site boundaries. To combine advantages of both, the High- Performance Data Analysis (HPDA) Tier 3 concept opportunistically establishes data locality via coordinated caches. In accordance with HEP Tier 3 activities, the design incorporates two major assumptions: First, only a fraction of data is accessed regularly and thus the deciding factor for overall throughput. Second, data access may fallback to non-local, making permanent local data availability an inefficient resource usage strategy. Based on this, the HPDA design generically extends available storage hierarchies into the batch system. Using the batch system itself for scheduling file locality, an array of independent caches on the worker nodes is dynamically populated with high-profile data. Cache state information is exposed to the batch system both for managing caches and scheduling jobs. As a result, users directly work with a regular, adequately sized storage system. However, their automated batch processes are presented with local replications of data whenever possible.

  4. modelling and simulation of the batch hydrolysis of acetic ing

    eobe

    The kinetic modelling of the batch synthesis of acetic acid from acetic. The kinetic modelling of ... integral method of analysis to determine the kinetic parameters .... Equation (5) is applied to all the components ... In common chemical engineering terminology, the degree of ..... of Physical Organic Chemistry, Vol. 25, Number ...

  5. Comparison of neptunium sorption results using batch and column techniques

    Triay, I.R.; Furlano, A.C.; Weaver, S.C.; Chipera, S.J.; Bish, D.L.

    1996-08-01

    We used crushed-rock columns to study the sorption retardation of neptunium by zeolitic, devitrified, and vitric tuffs typical of those at the site of the potential high-level nuclear waste repository at Yucca Mountain, Nevada. We used two sodium bicarbonate waters (groundwater from Well J-13 at the site and water prepared to simulate groundwater from Well UE-25p No. 1) under oxidizing conditions. It was found that values of the sorption distribution coefficient, Kd, obtained from these column experiments under flowing conditions, regardless of the water or the water velocity used, agreed well with those obtained earlier from batch sorption experiments under static conditions. The batch sorption distribution coefficient can be used to predict the arrival time for neptunium eluted through the columns. On the other hand, the elution curves showed dispersivity, which implies that neptunium sorption in these tuffs may be nonlinear, irreversible, or noninstantaneous. As a result, use of a batch sorption distribution coefficient to calculate neptunium transport through Yucca Mountain tuffs would yield conservative values for neptunium release from the site. We also noted that neptunium (present as the anionic neptunyl carbonate complex) never eluted prior to tritiated water, which implies that charge exclusion does not appear to exclude neptunium from the tuff pores. The column experiments corroborated the trends observed in batch sorption experiments: neptunium sorption onto devitrified and vitric tuffs is minimal and sorption onto zeolitic tuffs decreases as the amount of sodium and bicarbonate/carbonate in the water increases

  6. Using physical properties of molten glass to estimate glass composition

    Choi, Kwan Sik; Yang, Kyoung Hwa; Park, Jong Kil

    1997-01-01

    A vitrification process is under development in KEPRI for the treatment of low-and medium-level radioactive waste. Although the project is for developing and building Vitrification Pilot Plant in Korea, one of KEPRI's concerns is the quality control of the vitrified glass. This paper discusses a methodology for the estimation of glass composition by on-line measurement of molten glass properties, which could be applied to the plant for real-time quality control of the glass product. By remotely measuring viscosity and density of the molten glass, the glass characteristics such as composition can be estimated and eventually controlled. For this purpose, using the database of glass composition vs. physical properties in isothermal three-component system of SiO 2 -Na 2 O-B 2 O 3 , a software TERNARY has been developed which determines the glass composition by using two known physical properties (e.g. density and viscosity)

  7. Superductile bulk metallic glass

    Yao, K.F.; Ruan, F.; Yang, Y.Q.; Chen, N.

    2006-01-01

    Usually, monolithic bulk metallic glasses undergo inhomogeneous plastic deformation and exhibit poor ductility (<2%) at room temperature. We report a newly developed Pd-Si binary bulk metallic glass, which exhibits a uniform plastic deformation and a large plastic engineering strain of 82% and a plastic true strain of 170%, together with initial strain hardening, slight strain softening and final strain hardening characteristics. The uniform shear deformation and the ultrahigh plasticity are mainly attributed to strain hardening, which results from the nanoscale inhomogeneity due to liquid phase separation. The formed nanoscale inhomogeneity will hinder, deflect, and bifurcate the propagation of shear bands

  8. Determination of Reportable Radionuclides for DWPF Sludge Batch 2 (Macro Batch 3)

    Bibler, N.E.

    2002-01-01

    The Waste Acceptance Product Specifications (WAPS) 1.2 require that ''The Producer shall report the inventory of radionuclides (in Curies) that have half-lives longer than 10 years and that are, or will be, present in concentrations greater than 0.05 percent of the total inventory for each waste type indexed to the years 2015 and 3115''. As part of the strategy to meet WAPS 1.2, the Defense Waste Processing Facility (DWPF) will report for each waste type, all radionuclides (with half-lives greater than 10 years) that have concentrations greater than 0.01 percent of the total inventory from time of production through the 1100 year period from 2015 through 3115. The initial listing of radionuclides to be included is based on the design-basis glass as identified in the Waste Form Compliance Plan (WCP) and Waste Form Qualification Report (WQR). However, it is required that this list be expanded if other radionuclides with half-lives greater than 10 years are identified that meet the greater than 0.01 percent criterion for Curie content

  9. Aging in a Structural Glass

    Kob, Walter; Barrat, Jean-Louis

    1998-01-01

    We discuss the relaxation dynamics of a simple structural glass which has been quenched below its glass transition temperature. We demonstrate that time correlation functions show strong aging effects and investigate in what way the fluctuation dissipation theorem is violated.

  10. Foam Glass for Construction Materials

    Petersen, Rasmus Rosenlund

    2016-01-01

    Foaming is commonly achieved by adding foaming agents such as metal oxides or metal carbonates to glass powder. At elevated temperature, the glass melt becomes viscous and the foaming agents decompose or react to form gas, causing a foamy glass melt. Subsequent cooling to room temperature, result...... in a solid foam glass. The foam glass industry employs a range of different melt precursors and foaming agents. Recycle glass is key melt precursors. Many parameters influence the foaming process and optimising the foaming conditions is very time consuming. The most challenging and attractive goal is to make...... low density foam glass for thermal insulation applications. In this thesis, it is argued that the use of metal carbonates as foaming agents is not suitable for low density foam glass. A reaction mechanism is proposed to justify this result. Furthermore, an in situ method is developed to optimise...

  11. Effect of the Callovian-Oxfordian clayey fraction on borosilicate glass alteration

    Debure, M.; Frugier, P.; GIN, S.; De Windt, L.; Michau, N.

    2012-01-01

    easily exchangeable Mg and to check whether remaining Mg, especially structural Mg could still feed the solution. The cation exchange capacity (CEC) and the exchangeable cation population after treatment were measured by the cobaltihexamine test, indicating an enrichment of Na (from 14% to 79% in equivalents) of the exchangeable population at the expense of Ca (from 50% to 4%), Mg (from 15% to 6%) and K (from 18% to 7%) compared to the pristine clay-stone. Synthetic borosilicate Mg-free glasses were used as simplified references of the French nuclear glass R7T7. Batch experiments were performed in closed system at 90 deg. C during 150 days. The clay/glass (C/G) weight ratio ranged from 0.01 to 100 for a liquid/solid (L/S) weight ratio of 20. The specific surface was estimated to be around 0.06 m 2 /g and 100 m 2 /g for the glass powder and the clayey fraction, respectively. Chemical analysis of the batch solutions were carried out with time, as well as XRD, SEM and TOF-SIMS analysis of the solids after completion of the batch experiments. Modeling was performed with the GRAAL kinetic model of glass dissolution that considers elements and water diffusion in the alteration layer (Frugier et al., 2008), implemented within the reactive transport code HYTEC (van der Lee et al., 2003). The experiments showed that the higher the clay/glass ratio, the lower the pH 90deg.C and the higher the glass alteration. As shown in Fig. 1, the pH 90deg.C varied from 8.9 for the lowest clay/glass proportion (C/G 1) to 5.4 for the highest one (C/G = 100). The corresponding mean glass dissolution rates are 15 nm/d and 300 nm/d, respectively. A batch test performed with the sole clayey fraction in pure water yielded a pH 90deg.C of 5.2, whereas the test made with the glass alone led to a pH 90deg.C around 9. The main effect of the clayey fraction in the batch tests seems to drop the pH down to more acidic values that concentrations of B (a tracer of the glass alteration) on the one hand, and of

  12. Glass ceilings of professionalisation.

    Stott, Dawn L

    2016-04-01

    The term glass ceiling is a political term often used to describe an unbreakable barrier that isnot visible with the human eye, but it keeps minorities from rising up i.e. it is a barrier to minoritygroups, in the past (and sometimes still) for women, that stops them from achieving theirtrue potential.

  13. What Glass Ceiling?

    Lynch, Michael; Post, Katherine

    1996-01-01

    A recent study drawing on data from the Census Bureau and the Bureau of Labor Statistics suggests that the wage gap between men and women has virtually disappeared, and that the so-called "glass ceiling" results more from age and qualifications than from explicit discrimination. (SLD)

  14. Metallic glasses: structural models

    Nassif, E.

    1984-01-01

    The aim of this work is to give a summary of the attempts made up to the present in order to discribe by structural models the atomic arrangement in metallic glasses, showing also why the structure factors and atomic distribution functions cannot be always experimentally determined with a reasonable accuracy. (M.W.O.) [pt

  15. Microchips on glass

    Nanver, L.; De Vreede, L.; Keulemans, M.

    2007-01-01

    Microchips on glass. What about a mobile phone that uses a single microchip to receive all the available frequency bands, plus extras such as television, gps, and Internet access? Or, in due time, see-though implants that will monitor your state of health, and equipment that will let you see through

  16. Glass as matter

    Beim, Anne

    2000-01-01

    Refraiming the Moderns - Substitute Windows and Glass. In general terms, the seminar has contributed to the growing interest in the problems concerning the restoration of Modern Movement architecture. More particularly, it has of course drawn our attention to modern windows, which are increasingly...

  17. Glass ... current issues

    Wright, A.F.; Dupuy, J.

    1985-01-01

    The objectives of the School were twofold. Firstly to inform participants of actual and developing technological applications of glassy materials in which fundamental science makes a strong contribution, and secondly to bring together scientists from the widely different backgrounds of glass science and technology to promote mutual understanding and collaboration. (orig.)

  18. Stained Glass and Flu

    2017-02-01

    Dr. Robert Webster, an Emeritus member of the Department of Infectious Diseases at St. Jude Children's Research Hospital, discusses his cover art story on stained glass and influenza.  Created: 2/1/2017 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/1/2017.

  19. Glasses and nuclear waste vitrification

    Ojovan, Michael I.

    2012-01-01

    Glass is an amorphous solid material which behaves like an isotropic crystal. Atomic structure of glass lacks long-range order but possesses short and most probably medium range order. Compared to crystalline materials of the same composition glasses are metastable materials however crystallisation processes are kinetically impeded within times which typically exceed the age of universe. The physical and chemical durability of glasses combined with their high tolerance to compositional changes makes glasses irreplaceable when hazardous waste needs immobilisation for safe long-term storage, transportation and consequent disposal. Immobilisation of radioactive waste in glassy materials using vitrification has been used successfully for several decades. Nuclear waste vitrification is attractive because of its flexibility, the large number of elements which can be incorporated in the glass, its high corrosion durability and the reduced volume of the resulting wasteform. Vitrification involves melting of waste materials with glass-forming additives so that the final vitreous product incorporates the waste contaminants in its macro- and micro-structure. Hazardous waste constituents are immobilised either by direct incorporation into the glass structure or by encapsulation when the final glassy material can be in form of a glass composite material. Both borosilicate and phosphate glasses are currently used to immobilise nuclear wastes. In addition to relatively homogeneous glasses novel glass composite materials are used to immobilise problematic waste streams. (author)

  20. Physical and mathematical modelling of gas-fired glass melting furnaces with regard to NO-formation

    May, F.; Stuchlik, O.; Kremer, H.

    1999-01-01

    The increasing demand in quality, efficiency, energy conservation and the environmental issues drive the operators of high temperature processes to optimize their furnaces. Especially the glass manufacturing industry with their high working temperatures from about 1850 K to more than 1950 K and high air preheating temperatures of above 1480 K will produce high NOx-concentrations in the flue gas if no primary measures are taken. Considering the three different paths for NO-formation it is obvious that increased thermal NO is responsible for higher emissions. The German environmental regulations on air ''TA Luft'' requires a maximum value of 500 mg/mN3 in the flue gas for most of the combustion processes but for glass melting furnaces a temporary regulation of 1200 mg/mN3 and further on to 800 mg/mN3 is valid. Due to economical reasons the level of secondary measures is to be minimized thus the main objective of research is to reduce the NOx-emissions via primary measures. The design of the furnace is very important due to its strong influence on the distribution of velocity and species. That consequently affects the temperature field and the heat transfer to the load and further on the emissions. For the understanding of the processes within these furnaces numerical simulations, which are successfully validated with experiments, can give valuable indications to optimize furnace design for the reduction of NOx-emissions. The glass melting furnace modelled here is a regenerative horseshoe furnace fired with natural gas. Combustion air is preheated within the regenerator onto a level of temperature of 1650 K. (author)

  1. Er3+-Al2O3 nanoparticles doping of borosilicate glass

    Massera, Jonathan; Petit, Laeticia; Hupa, Leena; Hupa, Mikko; Koponen, Joona; Glorieux, Benoit

    2015-01-01

    Novel borosilicate glasses were developed by adding in the glass batch Er 3+ -Al 2 O 3 nanoparticles synthetized by using a soft chemical method. A similar nanoparticle doping with modified chemical vapour deposition (MCVD) process was developed to increase the efficiency of the amplifying silica fibre in comparison to using MCVD and solution doping. It was shown that with the melt quench technique, a Er 3+ -Al 2 O 3 nanoparticle doping neither leads to an increase in the Er 3+ luminescence properties nor allows one to control the rare-earth chemical environment in a borosilicate glass. The site of Er 3+ in the Er 3+ -Al 2 O 3 nanoparticle containing glass seems to be similar as in glasses with the same composition prepared using standard raw materials. We suspect the Er 3+ ions to diffuse from the nanoparticles into the glass matrix. There was no clear evidence of the presence of Al 2 O 3 nanoparticles in the glasses after melting. (author)

  2. Application of field synergy principle for optimization fluid flow and convective heat transfer in a tube bundle of a pre-heater

    Hamid, Mohammed O.A.; Zhang, Bo; Yang, Luopeng

    2014-01-01

    The big problems facing solar-assisted MED (multiple-effect distillation) desalination unit are the low efficiency and bulky heat exchangers, which worsen its systematic economic feasibility. In an attempt to develop heat transfer technologies with high energy efficiency, a mathematical study is established, and optimization analysis using FSP (field synergy principle) is proposed to support meaning of heat transfer enhancement of a pre-heater in a solar-assisted MED desalination unit. Numerical simulations are performed on fluid flow and heat transfer characteristics in a circular and elliptical tube bundle. The numerical results are analyzed using the concept of synergy angle and synergy number as an indication of synergy between velocity vector and temperature gradient fields. Heat transfer in elliptical tube bundle is enhanced significantly with increasing initial velocity of the feed seawater and field synergy number and decreasing of synergy angle. Under the same operating conditions of the two designs, the total average synergy angle is 78.97° and 66.31° in circular and elliptical tube bundle, respectively. Optimization of the pre-heater by FSP shows that in case of elliptical tube bundle design, the average synergy number and heat transfer rate are increased by 22.68% and 35.98% respectively. - Highlights: • FSP (field synergy principle) is used to investigate heat transfer enhancement. • Numerical simulations are performed in circular and elliptical tubes pre-heater. • Numerical results are analyzed using concept of synergy angle and synergy number. • Optimization of elliptical tube bundle by FSP has better performance

  3. Feasibility and economic analysis of solid desiccant wheel used for dehumidification and preheating in blast furnace: A case study of steel plant, Nanjing, China

    Guan, Yipeng; Zhang, Yufeng; Sheng, Ying; Kong, Xiangrui; Du, Song

    2015-01-01

    To overcome the shortcomings of huge energy consumption from conventional dehumidification using lithium bromide adsorption refrigerating (LBARD) system, a novel desiccant wheel dehumidification and preheating (DWDP) system using two-stage desiccant wheel for blast furnace is brought forward. The DWDP system was designed for dehumidification and preheating in blast furnace of steel plant. It takes waste heat in the slag flushing water as desiccant regeneration and preheating energy. To validate the feasibility of the new DWDP system, experimental studies were conducted based on a steel plant in Nanjing, China. The experiment was designed to use DWDP system in humid outdoor climates e.g. summer seasons. The experimental results indicate that the moisture removal capacity of DWDP system can reach 8.7 g/kg which will lead to the improvement of steel production by 0.9% and the coal is saved of about 2100 tons per year. With the DWDP system, the energy consumed by cooling tower of slag flushing water can decrease 7.3%. All of these energy saved equates to 10.3 million CNY annually. A comparison of initial investment and operating cost between DWDP system and LBRAD system was then carried out. The results show that the initial investment and operating cost of DWDP system is 37% and 57% of present LBARD system, and the payback period is shortened 66%. - Highlights: • A novel two-stage desiccant wheel dehumidification system for blast furnace is proposed. • Average moisture removal of 8.7 g/kg is achieved and dehumidification efficiency is 47%. • Outlet humidity ratio is less than 10 g/kg that satisfies the requirement of blast air. • Waste heat in slag flushing water is utilized and 61.4 million kJ is saved annually. • The investment and operating cost is 37% and 57% of former dehumidification system

  4. DETERMINATION OF REPORTABLE RADIONUCLIDES FOR DWPF SLUDGE BATCH 4 MACROBATCH 5

    Bannochie, C; Ned Bibler, N; David Diprete, D

    2008-01-01

    The Waste Acceptance Product Specifications (WAPS)1 1.2 require that 'The Producer shall report the inventory of radionuclides (in Curies) that have half-lives longer than 10 years and that are, or will be, present in concentrations greater than 0.05 percent of the total inventory for each waste type indexed to the years 2015 and 3115'. As part of the strategy to meet WAPS 1.2, the Defense Waste Processing Facility (DWPF) will report for each waste type, all radionuclides (with half-lives greater than 10 years) that have concentrations greater than 0.01 percent of the total inventory from time of production through the 1100 year period from 2015 through 3115. The initial listing of radionuclides to be included is based on the design-basis glass as identified in the Waste Form Compliance Plan (WCP)2 and Waste Form Qualification Report (WQR)3. However, it is required that this list be expanded if other radionuclides with half-lives greater than 10 years are identified that may meet the greater than 0.01% criterion for Curie content. Specification 1.6 of the WAPS, International Atomic Energy Agency (IAEA) Safeguards Reporting for High Level Waste (HLW), requires that the ratio by weights of the following uranium and plutonium isotopes be reported: U-233, U-234, U-235, U-236, U-238, Pu-238, Pu-239, Pu-240, Pu-241, and Pu-242. Therefore, the complete set of reportable radionuclides must also include this set of U and Pu isotopes. The DWPF is receiving radioactive sludge slurry from HLW Tank 40. The radioactive sludge slurry in Tank 40 is a blend of the previous contents of Tank 40 (Sludge Batch 3) and the sludge that was transferred to Tank 40 from Tank 51. The blend of sludge from Tank 51 and Tank 40 defines Sludge Batch 4 (also referred to as Macrobatch 5 (MB5)). This report develops the list of reportable radionuclides and associated activities and determines the radionuclide activities as a function of time. The DWPF will use this list and the activities as one of

  5. Low-cost commercial glass beads as dosimeters in radiotherapy

    Jafari, S.M.; Bradley, D.A.; Gouldstone, C.A.; Sharpe, P.H.G.; Alalawi, A.; Jordan, T.J.; Clark, C.H.; Nisbet, A.; Spyrou, N.M.

    2014-01-01

    Recent developments in advanced radiotherapy techniques using small field photon beams, require small detectors to determine the delivered dose in steep dose gradient fields. Commercially available glass jewellery beads exhibit thermoluminescent properties and have the potential to be used as dosimeters in radiotherapy due to their small size ( 60 Co gamma rays over doses ranging from 1 to 2500 cGy. A thermoluminescence (TL) system and an electron paramagnetic resonance (EPR) system were employed for read out. Both the TL and EPR studies demonstrated a radiation-induced signal, the sensitivity of which varied with bead colour. White coloured beads proved to be the most sensitive for both systems. The smallest and therefore least sensitive bead sizes allowed measurement of doses of 1 cGy using the TL system while that for the EPR system was approximately 1000 cGy. The fading rate was found to be 10% 30 days after irradiation with both readout systems. The dose response is linear with measured dose over the dose range 1 to 2500 cGy, with an R 2 correlation coefficient of greater than 0.999. The batch-to-batch reproducibility of a set of dosimeters after a single irradiation was found to be 3% (1 SD). The reproducibility of individual dosimeters was found to be 1.7%. No measurable angular dependence was found (results agreed within 1%). Dose rate response was found to agree within 1% for dose rates of 100 to 600 cGy/min. These results demonstrate the potential use of glass beads as TL dosimeters over the dose range commonly applied in radiotherapy. - Highlights: • We examined the dosimetric properties of a low cost commercially produced glass seed beads. • Glass beads are available in small size of 1–3 mm, suitable for dosimetry of small radiation fields. • The results demonstrate a mean reproducibility of 0.23% (2 SD), batch homogeneity of within 5%. • Dose response was linear over wide dose range tested for 1 cGy to kGy. • Improved fading effect of 10

  6. Apollo 12 ropy glasses revisited

    Wentworth, S. J.; Mckay, D. S.; Lindstrom, D. J.; Basu, A.; Martinez, R. R.; Bogard, D. D.; Garrison, D. H.

    1994-01-01

    We analyzed ropy glasses from Apollo 12 soils 12032 and 12033 by a variety of techniques including SEM/EDX, electron microprobe analysis, INAA, and Ar-39-Ar-40 age dating. The ropy glasses have potassium rare earth elements phosphorous (KREEP)-like compositions different from those of local Apollo 12 mare soils; it is likely that the ropy glasses are of exotic origin. Mixing calculations indicate that the ropy glasses formed from a liquid enriched in KREEP and that the ropy glass liquid also contained a significant amount of mare material. The presence of solar Ar and a trace of regolith-derived glass within the ropy glasses are evidence that the ropy glasses contain a small regolith component. Anorthosite and crystalline breccia (KREEP) clasts occur in some ropy glasses. We also found within these glasses clasts of felsite (fine-grained granitic fragments) very similar in texture and composition to the larger Apollo 12 felsites, which have a Ar-39-Ar-40 degassing age of 800 +/- 15 Ma. Measurements of 39-Ar-40-Ar in 12032 ropy glass indicate that it was degassed at the same time as the large felsite although the ropy glass was not completely degassed. The ropy glasses and felsites, therefore, probably came from the same source. Most early investigators suggested that the Apollo 12 ropy glasses were part of the ejecta deposited at the Apollo 12 site from the Copernicus impact. Our new data reinforce this model. If these ropy glasses are from Copernicus, they provide new clues to the nature of the target material at the Copernicus site, a part of the Moon that has not been sampled directly.

  7. SLUDGE WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS FOR SLUDGE BATCH 5 QUALIFICATION

    Pareizs, J; Cj Bannochie, C; Damon Click, D; Dan Lambert, D; Michael Stone, M; Bradley Pickenheim, B; Amanda Billings, A; Ned Bibler, N

    2008-11-10

    Sludge Batch 5 (SB5) is predominantly a combination of H-modified (HM) sludge from Tank 11 that underwent aluminum dissolution in late 2007 to reduce the total mass of sludge solids and aluminum being fed to the Defense Waste Processing Facility (DWPF) and Purex sludge transferred from Tank 7. Following aluminum dissolution, the addition of Tank 7 sludge and excess Pu to Tank 51, Liquid Waste Operations (LWO) provided the Savannah River National Laboratory (SRNL) a 3-L sample of Tank 51 sludge for SB5 qualification. SB5 qualification included washing the sample per LWO plans/projections (including the addition of a Pu/Be stream from H Canyon), DWPF Chemical Process Cell (CPC) simulations, waste glass fabrication (vitrification), and waste glass chemical durability evaluation. This report documents: (1) The washing (addition of water to dilute the sludge supernatant) and concentration (decanting of supernatant) of the Tank 51 qualification sample to adjust sodium content and weight percent insoluble solids to Tank Farm projections. (2) The performance of a DWPF CPC simulation using the washed Tank 51 sample. This includes a Sludge Receipt and Adjustment Tank (SRAT) cycle, where acid is added to the sludge to destroy nitrite and remove mercury, and a Slurry Mix Evaporator (SME) cycle, where glass frit is added to the sludge in preparation for vitrification. The SME cycle also included replication of five canister decontamination additions and concentrations. Processing parameters for the CPC processing were based on work with a non radioactive simulant. (3) Vitrification of a portion of the SME product and Product Consistency Test (PCT) evaluation of the resulting glass. (4) Rheology measurements of the initial slurry samples and samples after each phase of CPC processing. This work is controlled by a Task Technical and Quality Assurance Plan (TTQAP) , and analyses are guided by an Analytical Study Plan. This work is Technical Baseline Research and Development (R

  8. An Analysis of the Microstructure, Macrostructure and Microhardness of Nicr-Ir Joints Produced by Laser Welding with and without Preheat

    Różowicz S.

    2016-06-01

    Full Text Available This paper discusses some of the basic problems involved in laser welding of dissimilar materials with significant differences in melting points. It focuses on the micro and macrostructure of laser welded NiCr-Ir microjoints used in central spark plug electrodes. The joints were produced by welding with and without preheat using an Nd,YAG laser. The structure and composition of the welded joints were analyzed by means of a light microscope (LM and a scanning electron microscope (SEM equipped with an energy dispersive X-ray (EDX spectrometer. The microhardness of the weld area was also studied.

  9. A Novel TiQ2-Assisted Solar Photocatalytic Batch-Process Disinfection Reactor for the Treatment of Biological and Chemical Contaminants in Domestic Drinking Water in Developing Countries

    Duffy, E. F.; Al Touati, F.; Kehoe, S. C.; McLoughlin, O. A.; Gill, L. W.; Gernjak, W.; Oller, I.; Maldonado, M. I.; Malato, S.; Cassidy, John; Reed, R. H.; McGuigan, K. G.

    2004-01-01

    he technical feasibility and performance of photocatalytic Ti02 coatings in batch-process solar disinfection (SODIS) reactors to improve potability of drinking water in developing countries have been studied. Borosilicate glass and PET plastic SODIS reactors fitted with flexible plastic inserts coated with Ti02 powder were shown to be 2(Jt1o and 25% more effective, respectively, than standard SODIS reactors for the inactivation of E. coli K12. Isopropanol at 100 ppm concentration levels was o...

  10. Glass bead cultivation of fungi

    Droce, Aida; Sørensen, Jens Laurids; Giese, H.

    2013-01-01

    Production of bioactive compounds and enzymes from filamentous fungi is highly dependent on cultivation conditions. Here we present an easy way to cultivate filamentous fungi on glass beads that allow complete control of nutrient supply. Secondary metabolite production in Fusarium graminearum...... and Fusarium solani cultivated on agar plates, in shaking liquid culture or on glass beads was compared. Agar plate culture and glass bead cultivation yielded comparable results while liquid culture had lower production of secondary metabolites. RNA extraction from glass beads and liquid cultures was easier...... to specific nutrient factors. •Fungal growth on glass beads eases and improves fungal RNA extraction....

  11. Sodium diffusion in boroaluminosilicate glasses

    Smedskjaer, Morten M.; Zheng, Qiuju; Mauro, John C.

    2011-01-01

    of isothermal sodium diffusion in BAS glasses by ion exchange, inward diffusion, and tracer diffusion experiments. By varying the [SiO2]/[Al2O3] ratio of the glasses, different structural regimes of sodium behavior are accessed. We show that the mobility of the sodium ions decreases with increasing [SiO2]/[Al2O......Understanding the fundamentals of alkali diffusion in boroaluminosilicate (BAS) glasses is of critical importance for advanced glass applications, e.g., the production of chemically strengthened glass covers for personal electronic devices. Here, we investigate the composition dependence...

  12. Continuous Heterogeneous Photocatalysis in Serial Micro-Batch Reactors.

    Pieber, Bartholomäus; Shalom, Menny; Antonietti, Markus; Seeberger, Peter H; Gilmore, Kerry

    2018-01-29

    Solid reagents, leaching catalysts, and heterogeneous photocatalysts are commonly employed in batch processes but are ill-suited for continuous-flow chemistry. Heterogeneous catalysts for thermal reactions are typically used in packed-bed reactors, which cannot be penetrated by light and thus are not suitable for photocatalytic reactions involving solids. We demonstrate that serial micro-batch reactors (SMBRs) allow for the continuous utilization of solid materials together with liquids and gases in flow. This technology was utilized to develop selective and efficient fluorination reactions using a modified graphitic carbon nitride heterogeneous catalyst instead of costly homogeneous metal polypyridyl complexes. The merger of this inexpensive, recyclable catalyst and the SMBR approach enables sustainable and scalable photocatalysis. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Optimal Operation of Industrial Batch Crystallizers : A Nonlinear Model-based Control Approach

    Mesbah, A.

    2010-01-01

    Batch crystallization is extensively employed in the chemical, pharmaceutical, and food industries to separate and purify high value-added chemical substances. Despite their widespread application, optimal operation of batch crystallizers is particularly challenging. The difficulties primarily

  14. Numerical study of cullet glass subjected to microwave heating and SiC susceptor effects. Part II: Exergy transfer analysis

    Acevedo, Luis; Usón, Sergio; Uche, Javier

    2015-01-01

    Highlights: • Exergy transfer analysis is proposed for the analysis of microwave glass heating. • Distribution of exergy transferred, accumulated and destroyed is quantified. • The method is applied to the comparison of different susceptor positions. - Abstract: The mathematical model of exergy transfer in cullet glass heated by microwave inside of a cubical cavity with the aid of a susceptor is presented. Part I of this paper presented a numerical combined electromagnetic and heat transfer model by applying both transient Maxwell’s equations and heat transfer equations. Then, the electromagnetic and temperature fields were used to obtain the exergy transfer analysis in the oven. Exergy transfer analysis informs us about the efficiency of energy transformations taking place during the heating process, since it explains how the quality of the energy behaves along the heating process. The rate of internal exergy, exergy flowing and destroyed exergy were obtained and presented for this transient process. Part I showed that the susceptor location could change the temperature fields of cullet glass. So, an exergy analysis is important to understand the irreversibilities produced by a susceptor during preheating (microwaves activation) and heating process of the cullet glass, and how they could be minimized. Exergy transfer analysis shows how both, electromagnetic and heat transfer, are responsible of the irreversibilities generated in the heating process

  15. A parallel ILP algorithm that incorporates incremental batch learning

    Nuno Fonseca; Rui Camacho; Fernado Silva

    2003-01-01

    In this paper we tackle the problems of eciency and scala-bility faced by Inductive Logic Programming (ILP) systems. We proposethe use of parallelism to improve eciency and the use of an incrementalbatch learning to address the scalability problem. We describe a novelparallel algorithm that incorporates into ILP the method of incremen-tal batch learning. The theoretical complexity of the algorithm indicatesthat a linear speedup can be achieved.

  16. Automated handling for SAF batch furnace and chemistry analysis operations

    Bowen, W.W.; Sherrell, D.L.; Wiemers, M.J.

    1981-01-01

    The Secure Automated Fabrication Program is developing a remotely operated breeder reactor fuel pin fabrication line. The equipment will be installed in the Fuels and Materials Examination Facility being constructed at Hanford, Washington. Production is scheduled to start in mid-1986. The application of small pneumatically operated industrial robots for loading and unloading product into and out of batch furnaces and for distribution and handling of chemistry samples is described

  17. Integration of virtualized worker nodes in standard batch systems

    Buege, Volker; Kunze, Marcel; Oberst, Oliver; Quast, Guenter; Scheurer, Armin; Hessling, Hermann; Kemp, Yves; Synge, Owen

    2010-01-01

    Current experiments in HEP only use a limited number of operating system flavours. Their software might only be validated on one single OS platform. Resource providers might have other operating systems of choice for the installation of the batch infrastructure. This is especially the case if a cluster is shared with other communities, or communities that have stricter security requirements. One solution would be to statically divide the cluster into separated sub-clusters. In such a scenario, no opportunistic distribution of the load can be achieved, resulting in a poor overall utilization efficiency. Another approach is to make the batch system aware of virtualization, and to provide each community with its favoured operating system in a virtual machine. Here, the scheduler has full flexibility, resulting in a better overall efficiency of the resources. In our contribution, we present a lightweight concept for the integration of virtual worker nodes into standard batch systems. The virtual machines are started on the worker nodes just before jobs are executed there. No meta-scheduling is introduced. We demonstrate two prototype implementations, one based on the Sun Grid Engine (SGE), the other using Maui/Torque as a batch system. Both solutions support local job as well as Grid job submission. The hypervisors currently used are Xen and KVM, a port to another system is easily envisageable. To better handle different virtual machines on the physical host, the management solution VmImageManager is developed. We will present first experience from running the two prototype implementations. In a last part, we will show the potential future use of this lightweight concept when integrated into high-level (i.e. Grid) work-flows.

  18. Hydrothermal liquefaction of biomass: Developments from batch to continuous process

    Elliott, DC; Biller, P; Ross, AB; Schmidt, AJ; Jones, SB

    2015-01-01

    This review describes the recent results in hydrothermal liquefaction (HTL) of biomass in continuous-flow processing systems. Although much has been published about batch reactor tests of biomass HTL, there is only limited information yet available on continuous-flow tests, which can provide a more reasonable basis for process design and scale-up for commercialization. High-moisture biomass feedstocks are the most likely to be used in HTL. These materials are described and results of their pr...

  19. Batch production of microchannel plate photo-multipliers

    Frisch, Henry J.; Wetstein, Matthew; Elagin, Andrey

    2018-03-06

    In-situ methods for the batch fabrication of flat-panel micro-channel plate (MCP) photomultiplier tube (PMT) detectors (MCP-PMTs), without transporting either the window or the detector assembly inside a vacuum vessel are provided. The method allows for the synthesis of a reflection-mode photocathode on the entrance to the pores of a first MCP or the synthesis of a transmission-mode photocathode on the vacuum side of a photodetector entrance window.

  20. BATCH PROCESS INTEGRATION OF APPLYING TECHNOLOGY OF ACID CARMINIC PINCH

    Erazo E., Raymundo; Cárdenas R., Jorge L.; Woolcott H., Juan C.

    2014-01-01

    This work was developed in order to implement the PINCH technology integration batch process for carminic acid. The method used consisted of the application of the concepts of bottle necks total process (OPB) together with part-time models (TAM) and time fractionated! (TSM). The drying operation is identified as the rate limiting step of the process identifying it as an OPB plant capacity. The extraction yield was 95% w / p carminic acid with an energy savings of approximately 60% of the...