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Sample records for aged catalyst extrudates

  1. Early-age volume changes of extrudable reactive powder concrete

    OpenAIRE

    De Noirfontaine M.N.; Mounanga P.; Khelidj A.; Dunstetter F.; Cherkaoui K.; Courtial M.

    2010-01-01

    This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs), especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP), have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  2. Early-age volume changes of extrudable reactive powder concrete

    Directory of Open Access Journals (Sweden)

    De Noirfontaine M.N.

    2010-06-01

    Full Text Available This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs, especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP, have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  3. Early-age volume changes of extrudable reactive powder concrete

    Science.gov (United States)

    Cherkaoui, K.; Courtial, M.; Dunstetter, F.; Khelidj, A.; Mounanga, P.; de Noirfontaine, M. N.

    2010-06-01

    This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs), especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP), have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  4. Cyclic deformation and fatigue of extruded ZK60 magnesium alloy with aging effects

    International Nuclear Information System (INIS)

    Monotonic and fully reversed strain-controlled cyclic deformation experiments were conducted on a ZK60 magnesium (Mg) alloy in as-extruded and T5 aged conditions in ambient air. It was observed that the aging process had a significant influence on the stress–strain response and the fracture stress and strain under both monotonic tension and monotonic compression but a marginal influence on the stabilized cyclic deformation and fatigue of the material. An Electron Backscatter Diffraction (EBSD) analysis revealed that double twins were formed under a large compression strain in the as-extruded Mg but were not observed in the aged state under monotonic compression. A kink point in the strain-life fatigue curve demarcates the influence of twinning–detwinning deformation on fatigue. No twinning occurred throughout the fatigue life of the material when the strain amplitude was lower than the kink point value. With a strain amplitude slightly above the kink point, twinning–detwinning occurred but the process diminished as the loading cycle increased. The aging process enhanced the kink point slightly from a strain amplitude of 0.32% to 0.35%. Only small amount residual twins were observed in the material after fatigue loading when the strain amplitudes were lower than 4%

  5. Green and early age compressive strength of extruded cement mortar monitored with compression tests and ultrasonic techniques

    International Nuclear Information System (INIS)

    Knowledge about the early age compressive strength development of cementitious materials is an important factor for the progress and safety of many construction projects. This paper uses cylindrical mortar specimens produced with a ram extruder to investigate the transition of the mortar from plastic and deformable to hardened state. In addition, wave transmission and reflection measurements with P- and S-waves were conducted to obtain further information about the microstructural changes during the setting and hardening process. The experiments have shown that uniaxial compression tests conducted on extruded mortar cylinders are a useful tool to evaluate the green strength as well as the initiation and further development of the compressive strength of the tested material. The propagation of P-waves was found to be indicative of the internal structure of the tested mortars as influenced, for example, by the addition of fine clay particles. S-waves used in transmission and reflection mode proved to be sensitive to the inter-particle bonding caused by the cement hydration and expressed by an increase in compressive strength

  6. Effect of ageing treatment on the microstructures and mechanical properties of the extruded Mg-7Y-4Gd-1.5Zn-0.4Zr alloy

    International Nuclear Information System (INIS)

    Microstructures and mechanical properties of Mg-7Y-4Gd-1.5Zn-0.4Zr alloy in the as-cast, as-extruded and peak-aged conditions have been investigated by using optical microscope, scanning electron microscope, X-ray diffraction and transmission electron microscope. The results show that optimal mechanical properties of this alloy are obtained when it was aged at 220 deg. C. The values of the ultimate tensile strength and yield tensile strength are 418 and 320 MPa, respectively. The age hardening response decreases with increasing ageing temperature because the β' phase gets coarse as ageing temperature increases.

  7. Simulation three-way catalyst ageing. Analysis of two conventional catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Martin, L.; Arranz, J.L.; Galan, M.A. [Departamento de Ingenieria Quimica y Textil, Universidad de Salamanca, Salamanca (Spain); Prieto, O.; Trujillano, R.; Holgado, M.J.; Rives, V. [Departamento de Quimica Inorganica, Universidad de Salamanca, Plaza de la Merced s/n 1-5, 37008 Salamanca (Spain)

    2003-08-08

    Two commercial automobile three-way catalysts (RENAULT) of different configuration: (I) Pt, Rh active phase supported on ceria-promoted alumina washcoat, and (II) Pd, Rh active phase supported on zirconia-ceria-promoted alumina washcoat on cordierite supports, have been compared fresh and aged in a conventional automobile for 100,000km in order to design and to adjust a catalyst ageing method suitable to imitate most relevant conditions of real tests. The characterization techniques were N{sub 2} adsorption-desorption isotherms, powder X-Ray diffraction, elemental chemical analysis and activity tests. Activity tests were: (1) CO, NO and CH{sub 4} conversion versus temperature (from 120 to 500C), and (2) CO, NO and CH{sub 4} conversion versus the ratio between the concentrations of the oxidant and reducing species ({lambda}) at 500C (normal running temperature). Gas composition was close to conventional engine exhaust composition with and without water vapour. A strong deactivation has been observed as a consequence of thermal processes and loss of catalyst washcoat mainly for catalyst (II). Poison concentration along the catalyst has also been shown, however, its influence on catalyst deactivation was not as important as thermal processes were.

  8. Extrudate versus Powder Silica Alumina as Support for Re2O7 Catalyst in the Metathesis of Seed Oil-Derivatives – A Comparison

    Directory of Open Access Journals (Sweden)

    Bassie B. Marvey

    2009-01-01

    Full Text Available Self- and cross-metathesis of fatty acid methyl esters (FAMEs was investigated using a silica alumina supported Re2O7 catalyst. Although a 3 wt% Re2O7/SiO2-Al2O3/SnBu4 is already active for the metathesis of unsaturated FAMEs, the results have shown that particle size of silica alumina support has a profound influence on its activity and selectivity. Consequently, high substrate conversions coupled with improved product yields (for mono- and diesters and reaction rates were obtained upon using powder, as opposed to extrudate silica alumina as the support material. Diesters are platform compounds for the synthesis of polymers and fragrances. In this paper a comparative outline of the influence of particle size of silica alumina (extrudate versus powder on catalytic performance of a 3 wt% Re2O7/SiO2-Al2O3/SnBu4 for self- and cross-metathesis of FAMEs is made. Low surface area and diffusion constraints associated with extrudates were identified as some of the factors leading to low catalytic activity and selectivity.

  9. Extruded Plastic Scintillation Detectors

    CERN Document Server

    Pla-Dalmau, A; Mellott, K L; Pla-Dalmau, Anna; Bross, Alan D.; Mellott, Kerry L.

    1999-01-01

    As a way to lower the cost of plastic scintillation detectors, commercially available polystyrene pellets have been used in the production of scintillating materials that can be extruded into different profiles. The selection of raw materials is discussed. Two techniques to add wavelength shifting dopants to polystyrene pellets and to extrude plastic scintillating strips are described. Data on light yield and transmittance measurements are presented.

  10. Purging mixture for extruder

    OpenAIRE

    Okpala, Chukwubuike

    2015-01-01

    This thesis work focuses on compounding a mechanical purge mixture for extruders. The base resin for making the purge mixture is recycled High Density Polyethylene chosen for its high density and good processing temperature. The additives are mainly clay and sili-con dioxide added as filler and scrubbing materials respectively. The purge mixture was produced by mixing the base resin and additives in percentage ratios into five places la-beled A, B, C, D, and E. the mixtures were extruded and ...

  11. In operando Detection of Three-Way Catalyst Aging by a Microwave-Based Method: Initial Studies

    OpenAIRE

    Gregor Beulertz; Martin Votsmeier; Ralf Moos

    2015-01-01

    Initial studies on aging detection of three way catalysts with a microwave cavity perturbation method were conducted. Two physico-chemical effects correlate with the aging state. At high temperatures, the resonance frequencies for oxidized catalysts (λ = 1.02) are not influenced by aging, but are significantly affected by aging in the reduced case (λ = 0.98). The catalyst aging state can therefore potentially be inferred from the resonance frequency differences between reduced and oxidized...

  12. Insight into the effects of different ageing protocols on Rh/Al2O3 catalyst

    International Nuclear Information System (INIS)

    In this work, a catalyst of Rh loaded on Al2O3 was prepared by impregnating method with rhodium nitrate aqueous solution as the Rh precursor. The catalyst was aged under different protocols (lean, rich, inert and cyclic) to obtain several aged samples. All the Rh/Al2O3 samples were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) method, CO-chemisorption, H2-temperature programmed reduction (H2-TPR), transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). It was found that a specific ageing treatment could strongly affect the catalytic activity. The N2 aged and the H2 aged samples had a better catalytic activity for CO + NO reaction than the fresh sample while the air aged and the cyclic aged samples exhibited much worse activity. More surface Rh content and better reducibility were obtained in the N2 and the H2 aged samples and the Rh particles existed with an appropriate size, which were all favorable to the catalytic reaction. However, the air and the cyclic ageing protocols induced a strong interaction between Rh species and the Al2O3 support, which resulted in a severe sintering of particles of Rh species and the loss of active sites. The structure evolution scheme of the catalysts aged in different protocols was also established in this paper.

  13. Photo-spectroscopy of mixtures of catalyst particles reveals their age and type.

    Science.gov (United States)

    Kerssens, M M; Wilbers, A; Kramer, J; de Peinder, P; Mesu, G; Nelissen, B J; Vogt, E T C; Weckhuysen, B M

    2016-07-01

    Within a fluid catalytic cracking (FCC) unit, a mixture of catalyst particles that consist of either zeolite Y (FCC-Y) or ZSM-5 (FCC-ZSM-5) is used in order to boost the propylene yield when processing crude oil fractions. Mixtures of differently aged FCC-Y and FCC-ZSM-5 particles circulating in the FCC unit, the so-called equilibrium catalyst (Ecat), are routinely studied to monitor the overall efficiency of the FCC process. In this study, the age of individual catalyst particles is evaluated based upon photographs after selective staining with substituted styrene molecules. The observed color changes are linked to physical properties, such as the micropore volume and catalytic cracking activity data. Furthermore, it has been possible to determine the relative amount of FCC-Y and FCC-ZSM-5 in an artificial series of physical mixtures as well as in an Ecat sample with unknown composition. As a result, a new practical tool is introduced in the field of zeolite catalysis to evaluate FCC catalyst performances on the basis of photo-spectroscopic measurements with an off-the-shelf digital single lens reflex (DSLR) photo-camera with a macro lens. The results also demonstrate that there is an interesting time and cost trade-off between single catalyst particle studies, as performed with e.g. UV-vis, synchrotron-based IR and fluorescence micro-spectroscopy, and many catalyst particle photo-spectroscopy studies, making use of a relatively simple DSLR photo-camera. The latter approach offers clear prospects for the quality control of e.g. FCC catalyst manufacturing plants. PMID:27098521

  14. CATCOM catalyst 5 atm 1000 hour aging study using No. 2 fuel oil

    Science.gov (United States)

    Osgerby, I. T.; Olson, B. A.; Lee, H. C.

    1980-01-01

    The durability of the CATCOM catalyst for use in catalytically supported thermal combustion has been demonstrated at 5 atm, complementing a previous 1000 hour durability study at 1 atm. Both of these studies were conducted at about 640 K air preheat temperature at a reference velocity of about 14 m/s; the adiabatic flame temperature of the fuel/air mixture was about 1530 K. The catalyst proved to be capable of low emissions operations after 1000 hours of diesel fuel aging. However, more severe deactivation occurred in the 5 atm test; this was attributed to a loss in kinetic (ignition) activity.

  15. In operando Detection of Three-Way Catalyst Aging by a Microwave-Based Method: Initial Studies

    Directory of Open Access Journals (Sweden)

    Gregor Beulertz

    2015-07-01

    Full Text Available Initial studies on aging detection of three way catalysts with a microwave cavity perturbation method were conducted. Two physico-chemical effects correlate with the aging state. At high temperatures, the resonance frequencies for oxidized catalysts (λ = 1.02 are not influenced by aging, but are significantly affected by aging in the reduced case (λ = 0.98. The catalyst aging state can therefore potentially be inferred from the resonance frequency differences between reduced and oxidized states or from the resonance frequency amplitudes during lambda oscillations. Secondly, adsorbed water at low temperatures strongly affects the resonance frequencies. Light-off experiment studies showed that the resonance frequency depends on the aging state at temperatures below the oxygen storage light-off. These differences were attributed to different water sorption capabilities of differently aged samples due to a surface area decrease with proceeding aging. In addition to the aging state, the water content in the feed gas and the temperature affect the amount of adsorbed water, leading to different integral electrical material properties of the catalyst and changing the resonance properties of the catalyst-filled canning. The classical aging-related properties of the catalyst (oxygen storage capacity, oxygen storage light-off, surface area, agreed very well with data obtained by the microwave-based method.

  16. Physical properties of extrudates containing distillers grains extruded in a twin screw extruder

    Science.gov (United States)

    Extrusion trials were conducted with varying levels of distillers dried grains with solubles (DDGS) along with soy flour, corn flour, fish meal, vitamin mix, mineral mix and net protein content adjusted to 28% using a Wenger TX-52 twin screw extruder. The properties of extrudates obtained with exper...

  17. Optimal Parameters Multicomponent Mixtures Extruding

    Directory of Open Access Journals (Sweden)

    Ramil F. Sagitov

    2013-01-01

    Full Text Available Experimental research of multicomponent mixtures extruding from production wastes are carried out, unit for production of composites from different types of waste is presented. Having analyzed dependence of multicomponent mixtures extruding energy requirements on die length and components content at three values of angular rate of screw rotation, we received the values of energy requirements at optimal length of the die, angular speed and percent of binding additives.

  18. Deactivation Correlations of Pd/Rh Three-way Catalysts Designed for Euro IV Emission Limits:effect of Ageing Atmosphere, Temperature and Time

    OpenAIRE

    Lassi, U. (Ulla)

    2003-01-01

    Abstract The aim of this thesis is the knowledge of the most relevant deactivation mechanisms of Pd/Rh three-way catalysts under different ageing conditions, the deactivation correlation of laboratory scale ageing and engine bench/vehicle ageings, and the evaluation of the deactivation correlation. In the literature review, the phenomena involved in the three-way catalyst operation and its deactivation are considered. In the experimental section, ageing-induced phenomena in the catalyst ar...

  19. Ageing Effects on Exhaust Gas Catalysts: Microscopic Changes Captured by X-Ray Tomography

    Science.gov (United States)

    Hofmann, G.; Rochet, A.; Baier, S.; Casapu, M.; Ritter, S.; Wilde, F.; Ogurreck, M.; Beckmann, F.; Grunwaldt, J.-D.

    2014-04-01

    In this work we examine the different aspects of catalyst ageing with effects ranging from the nano to the macro scale. Underlining the general importance of combining different characterisation techniques, like transmission electron microscopy (TEM), X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) for the nanoscale, we focus on the application of X-ray absorption micro-computed tomography (micro-CT) to capture macroscopic changes in the um to mm scale. Two series of tomographic measurements were carried out: (i) investigation of three differently treated samples by collecting one channel from a fresh, a conditioned and an aged monolith and (ii) examination of one single coated honeycomb channel with 4 wt% Pt/γ-Al2O3 and for comparison one with pure γ-Al2O3 washcoat, which have been measured in a non-destructive ex situ manner at the same position after each ageing treatment. Main observations of the tomographic study are: (1) coating inhomogeneities between different channels taken from the same honeycomb and between different honeycombs, (2) formation of cracks in the washcoat material and (3) formation of macroscopic Pt particles in the case of 4 wt% Pt/γ-Al2O3 washcoat. Particularly valuable is the non-destructive ex situ investigation after different ageing steps on the same channel using X-ray tomography.

  20. CNC Extruder for varied section extrusion

    Directory of Open Access Journals (Sweden)

    H.J. Choi

    2008-08-01

    Full Text Available Purpose: The work presented in this paper might be used for basic data in the design of a lot extruded aluminum products using the variable section extrusion process.Design/methodology/approach: The capacity of a CNC extruder was calculated and decided as analyzing the FEM results performed by commercial software DEFORM-2D. CNC extruder and die set for variable section extrusion was invented by field extrusion experts.Findings: CNC extruder had a key role in variable extrusion process. Furthermore there was few die sets with mold feeding parts for aluminum extrusion. To be capable of extruding aluminum products with variable cross section are CNC extruder and the die set.Research limitations/implications: For future research of developed CNC extruder, frame structures of the extruder would be analyzed and designed using FE analysis. In addition CNC extruder would be operated by the control program for variable section as a PC version.Practical implications: Aluminum parts with variable section would increase as utilizing the CNC extruder and cost price of the parts be down. Many industrial products using the variable section extrusion process would be used in diverse fields.Originality/value: Extruded aluminum part with variable section is rarely used since extruders don’t be designed and developed for variable section extrusion. It is important that an extruder with CNC control, which could be easily handled and have accessible software to be operated by field user, are invented. As stated above, CNC extruder is needed for production of industrial products with variable section for today. Therefore design and development of CNC extruder having the die set for mold feeding parts was tackled in this paper as efficient approach using commercial FEM code.

  1. Nitrogen oxide reduction by carbon monoxide in the presence of oxygen over a fresh and aged Pd/alumina catalyst

    International Nuclear Information System (INIS)

    The reduction of nitrogen oxide with carbon monoxide in presence of oxygen over a palladium based catalyst is studied. Metal dispersion decreases with the thermal aging of the fresh solid in a wet and oxidant atmosphere. However, the aged solid shows a catalytic activity for the oxidation of carbon monoxide and the reduction of nitrogen oxide higher than the fresh solid. After reaction, particle sizes and surface state were determined. The state of oxidation and the kind of surface oxide are different for the fresh and aged solids

  2. Part I: A Comparative Thermal Aging Study on the Regenerability of Rh/Al2O3 and Rh/CexOy-ZrO2 as Model Catalysts for Automotive Three Way Catalysts

    Directory of Open Access Journals (Sweden)

    Qinghe Zheng

    2015-10-01

    Full Text Available The rhodium (Rh component in automotive three way catalysts (TWC experiences severe thermal deactivation during fuel shutoff, an engine mode (e.g., at downhill coasting used for enhancing fuel economy. In a subsequent switch to a slightly fuel rich condition, in situ catalyst regeneration is accomplished by reduction with H2 generated through steam reforming catalyzed by Rh0 sites. The present work reports the effects of the two processes on the activity and properties of 0.5% Rh/Al2O3 and 0.5% Rh/CexOy-ZrO2 (CZO as model catalysts for Rh-TWC. A very brief introduction of three way catalysts and system considerations is also given. During simulated fuel shutoff, catalyst deactivation is accelerated with increasing aging temperature from 800 °C to 1050 °C. Rh on a CZO support experiences less deactivation and faster regeneration than Rh on Al2O3. Catalyst characterization techniques including BET surface area, CO chemisorption, TPR, and XPS measurements were applied to examine the roles of metal-support interactions in each catalyst system. For Rh/Al2O3, strong metal-support interactions with the formation of stable rhodium aluminate (Rh(AlO2y complex dominates in fuel shutoff, leading to more difficult catalyst regeneration. For Rh/CZO, Rh sites were partially oxidized to Rh2O3 and were relatively easy to be reduced to active Rh0 during regeneration.

  3. Model bimetallic Pd-Ni automotive exhaust catalysts. Influence of thermal aging and hydrocarbon self-poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Hungria, A.B.; Martinez-Arias, A. [Instituto de Catalisis y Petroleoquimica, CSIC, C/Marie Curie 2, Campus Cantoblanco, 28049 Madrid (Spain); Calvino, J.J. [Dpto. de Ciencia de los Materiales e Ingenieria Metalurgica y Quimica Inorganica, Facultad de Ciencias, Universidad de Cadiz, 11510 Puerto Real, Cadiz (Spain); Anderson, J.A. [Surface Chemistry and Catalysis Group, Department of Chemistry, University of Aberdeen, AB24 3UE Scotland (United Kingdom)

    2006-02-22

    Bimetallic Pd-Ni catalysts supported on Al{sub 2}O{sub 3} and (Ce,Zr)O{sub x}/Al{sub 2}O{sub 3} were examined with respect to their catalytic performance for the elimination of CO, NO and C{sub 3}H{sub 6} under stoichiometric conditions. The effects of a thermal aging treatment at 1273K, reactant competition in the presence of the hydrocarbon and the influence of the presence of nickel in the catalyst have been analysed by XRD, HREM, catalytic activity measurements and in situ DRIFTS spectroscopy. Self-poisoning effects, induced by the presence of the hydrocarbon in the reactant mixture, were identified as the main factor affecting the light-off activity. While a Ni-induced preferential interaction between Pd and the Ce-Zr mixed oxide component appears, in general terms, to be beneficial for the catalytic performance of the fresh (Ce,Zr)O{sub x}/Al{sub 2}O{sub 3}-supported bimetallic catalyst, it is shown to be detrimental for the aged system as a consequence of a facilitated degradation of the (Ce,Zr)O{sub x} component and encapsulation of the active palladium particles. (author)

  4. Extrudate Expansion Modelling through Dimensional Analysis Method

    DEFF Research Database (Denmark)

    A new model framework is proposed to correlate extrudate expansion and extrusion operation parameters for a food extrusion cooking process through dimensional analysis principle, i.e. Buckingham pi theorem. Three dimensionless groups, i.e. energy, water content and temperature, are suggested to...... describe the extrudates expansion. From the three dimensionless groups, an equation with three experimentally determined parameters is derived to express the extrudate expansion. The model is evaluated with whole wheat flour and aquatic feed extrusion experimental data. The average deviations of the...

  5. VOx Surface Coverage Optimization of V2O5/WO3-TiO2 SCR Catalysts by Variation of the V Loading and by Aging

    Directory of Open Access Journals (Sweden)

    Adrian Marberger

    2015-10-01

    Full Text Available V2O5/WO3-TiO2 selective catalytic reduction (SCR catalysts with a V2O5 loading of 1.7, 2.0, 2.3, 2.6, 2.9, 3.2 and 3.5 wt. % were investigated in the fresh state and after hydrothermal aging at 600 °C for 16 h. The catalysts were characterized by means of nitrogen physisorption, X-ray diffraction and X-ray absorption spectroscopy. In the fresh state, the SCR activity increased with increasing V loading. Upon aging, the catalysts with up to 2.3 wt. % V2O5 exhibited higher NOx reduction activity than in the fresh state, while the catalysts with more than 2.6 wt. % V2O5 showed increasing deactivation tendencies. The observed activation and deactivation were correlated with the change of the VOx and WOx surface coverages. Only catalysts with a VOx coverage below 50% in the aged state did not show deactivation tendencies. With respect to tungsten, above one monolayer of WOx, WO3 particles were formed leading to loss of surface acidity, sintering, catalyst deactivation and early NH3 slip. An optimal compromise between activity and hydrothermal aging resistance could be obtained only with V2O5 between 2.0 and 2.6 wt. %.

  6. Development of an extruder-feeder biomass direct liquefaction process

    Energy Technology Data Exchange (ETDEWEB)

    White, D.H.; Wolf, D. (Arizona Univ., Tucson, AZ (United States). Dept. of Chemical Engineering)

    1991-10-01

    As an abundant, renewable, domestic energy resource, biomass could help the United States reduce its dependence on imported oil. Biomass is the only renewable energy technology capable of addressing the national need for liquid transportation fuels. Thus, there is an incentive to develop economic conversion processes for converting biomass, including wood, into liquid fuels. Through research sponsored by the US DOE's Biomass Thermochemical Conversion Program, the University of Arizona has developed a unique biomass direct liquefaction system. The system features a modified single-screw extruder capable of pumping solid slurries containing as high as 60 wt% wood flour in wood oil derived vacuum bottoms at pressures up to 3000 psi. The extruder-feeder has been integrated with a unique reactor by the University to form a system which offers potential for improving high pressure biomass direct liquefaction technology. The extruder-feeder acts simultaneously as both a feed preheater and a pumping device for injecting wood slurries into a high pressure reactor in the biomass liquefaction process. An experimental facility was constructed and following shakedown operations, wood crude oil was produced by mid-1985. By July 1988, a total of 57 experimental continuous biomass liquefaction runs were made using White Birch wood feedstock. Good operability was achieved at slurry feed rates up to 30 lb/hr, reactor pressures from 800 to 3000 psi and temperatures from 350{degree}C to 430{degree}C under conditions covering a range of carbon monoxide feed rates and sodium carbonate catalyst addition. Crude wood oils containing as little as 6--10 wt% residual oxygen were produced. 38 refs., 82 figs., 26 tabs.

  7. Experimental Study on Extruded Beer Adjunct Used for Brewing Beer

    Institute of Scientific and Technical Information of China (English)

    SHEN De-chao

    2004-01-01

    The properties of saccharified and boiled worts between extruded and traditional non-extruded beer adjuncts were studied at the laboratory and a small beer brewing equipment( 100 L) in this paper. Test results indicate that the main saccharification indices and filtration speeds of worts between extruded and traditional non-extruded beer adjuncts are similar basically. The collected rate of extracted material of worts of extruded beer adjuncts is 8%more than that of traditional non-extruded beer adjuncts. Fermentation time of worts of extruded beer adjuncts is 10 %less than that of traditional non-extruded beer adjuncts. The energy consumption of extruded beer adjuncts in saccharification process is 13 % less than that of traditional non-extruded beer adjuncts.

  8. Breadmaking characteristics of dough with extruded corn

    OpenAIRE

    N. Filipović; D. Šoronja Simović; V. Filipović

    2009-01-01

    Extrusion cooking is a thermal process often practiced in food, chemical and feed industry. Due to extrusion, nutritive value, texture, sensor characteristics and hygiene are improved. The influence of extruded corn grain and bread improver quantity on rheological and sensory characteristics of bread was investtigated in this paper. Experiment was planed according to factorial plan 32 with independent variables: quantity of extruded corn (10-30 % based in wheat flour, variation interval 10) a...

  9. Breadmaking characteristics of dough with extruded corn

    Directory of Open Access Journals (Sweden)

    N. Filipović

    2009-01-01

    Full Text Available Extrusion cooking is a thermal process often practiced in food, chemical and feed industry. Due to extrusion, nutritive value, texture, sensor characteristics and hygiene are improved. The influence of extruded corn grain and bread improver quantity on rheological and sensory characteristics of bread was investtigated in this paper. Experiment was planed according to factorial plan 32 with independent variables: quantity of extruded corn (10-30 % based in wheat flour, variation interval 10 and improver (0-0.4 % based on flour, variation interval 0.2. The influence of extruded corn on dough handling is illustrated by extensigraph data: in comparison to the dough without corn, area is decreasing 50 to 60 % and resistance to stretching 15 to 20 %. The addition of commercial bread improver, regardless the quantity of extruded corn is beneficial contributing to improved extensigraph data up to 30 %. By substituting wheat flour with 10 to 20 % of extruded corn along with proper quality of bread improver, bread quality is satisfying and stalling is significantly improved. In the production of so-called mixed corn bread (30 % of extruded corn extrusion is contributing to retard stalling and prolonged shelf-life.

  10. An advanced extruder-feeder biomass liquefaction reactor system

    Science.gov (United States)

    White, Don H.; Wolf, D.; Davenport, G.; Mathews, S.; Porter, M.; Zhao, Y.

    1987-11-01

    A unique method of pumping concentrated, viscous biomass slurries that are characteristic of biomass direct liquefaction systems was developed. A modified single-screw extruder was shown to be capable of pumping solid slurries as high as 60 weight percent wood flour in wood oil derived vacuum bottoms, as compared to only 10 to 20 weight percent wood flour in wood oil in conventional systems. During the period August, 1985 to April, 1987, a total of 18 experimental continuous biomass liquefaction runs were made using white birch feedstock. Good operability with feed rates up to 30 lb/hr covering a range of carbon monoxide, sodium carbonate catalyst, pressures from 800 to 3000 psi and temperatures from 350 C to 430 C was achieved. Crude wood oils containing 6 to 10 weight percent residual oxygen were obtained. Other wood oil characteristics are reported.

  11. Extruded Soybean Samples for Mechnical Oil Expression

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Soybean is generally recognized as a source of edible and the deoiled meal is seen as a source of protein in animal feed. In recent years. However,more interest has been directed toward using soy meal as a protein souce for human consumption. Extrusion-expelling of soybean provides an opportunity in this direction. The main focus of this study was to maximize the oil recovery from extruded soybean processed using three differ- ent kinds of extrudates and processing conditions. These extruded samples were later pressed uniaxially in a specifically designed test-cell and the oil recovery was recorded over time. The effects of process variables ,in- cluding applied pressure, pressing temperature and sample height, were investigated. Results indicated that over90% of the available oil could be recovered from pressing of extruded soy samples. The information gen- erated is likedly to be useful in interpreting the effect of precess variables and extruding equipment for pre- treatment of soybean for subsequent mechanical oil expression.

  12. VOx Surface Coverage Optimization of V2O5/WO3-TiO2 SCR Catalysts by Variation of the V Loading and by Aging

    OpenAIRE

    Adrian Marberger; Martin Elsener; Davide Ferri; Oliver Kröcher

    2015-01-01

    V2O5/WO3-TiO2 selective catalytic reduction (SCR) catalysts with a V2O5 loading of 1.7, 2.0, 2.3, 2.6, 2.9, 3.2 and 3.5 wt. % were investigated in the fresh state and after hydrothermal aging at 600 °C for 16 h. The catalysts were characterized by means of nitrogen physisorption, X-ray diffraction and X-ray absorption spectroscopy. In the fresh state, the SCR activity increased with increasing V loading. Upon aging, the catalysts with up to 2.3 wt. % V2O5 exhibited higher NOx reduction activ...

  13. Screw Extruder for Pellet Injection System

    Directory of Open Access Journals (Sweden)

    Sharadkumar K. Chhantbar

    2014-05-01

    Full Text Available Solid hydrogenic pellets are used as fuel for fusion energy reactor. A technique for continuous production of solid hydrogen and its isotopes by a screw extruder is suggested for the production of an unlimited number of pellets. The idea was developed and patented by PELIN laboratories, Inc. (Canada. A Gifford McMahon cryocooler is used for the generation of solid hydrogenic fluid pellets. Requirements of the pellets is depends upon the energy to be produced by tokamak. This review paper focuses on the model for the screw extruder for solidification of hydrogen ice having high injection reliability.

  14. Growth and Nutrient Utilization in Kids Fed Expander-extruded Complete Feed Pellets Containing Red Gram (Cajanus cajan) Straw

    OpenAIRE

    Reddy, P. B.; Reddy, T. J.; Reddy, Y. R.

    2012-01-01

    A growth and digestibility study was conducted using Osmanabadi goat male kids by feeding complete diets in the form of mash or expander extruded pellets containing different levels of red gram (Cajanus cajan) straw (RGS). Two iso-nitrogenous complete diets were prepared by incorporating RGS at 35% and 50% levels. Half the quantity of each complete mash feed was then converted into pellets through expander extruder processing. Thirty two kids of 4 to 5 months age were divided into four groups...

  15. RHEOLOGY OF EXTRUDED WHEY PROTEIN ISOLATE

    Science.gov (United States)

    Whey protein isolate (WPI), a high-quality protein used to fortify a number of foods, may be texturized with a twin-screw extruder. Since extrusion of food is commonly performed above 70°C, which causes whey protein to denature, cold extrusion below 70°C was investigated to determine the effects on...

  16. Experiment using laboratory scale extruder. Fluid behavior in twin-screw extruder

    International Nuclear Information System (INIS)

    All evidences and chemical data suggest non-chemical heating mechanism raised the filling temperature of the bituminized product. But they indicate the filling temperature was higher than before at the incident. We estimated the physical heat mechanism in the extruder. It is well known that the viscous-heating occurs in mixing process in extruders. In order to confirm the behavior of the torque and temperature, some experiment using laboratory scale extruder were performed. The result of the experiment using laboratory scale extruder showed that the phenomena of salt enrichment and salt accumulation were observed and they raised mixture temperature at the decreased feed rate. These phenomena depend on the feed rate. It is considered that they have large contribution to heat transportation and operational torque due to the friction between screw and mixture. In this report, all experiment result are explained. (author)

  17. A general extrudate bulk density model for both twin-screw and single-screw extruder extrusion cooking processes

    OpenAIRE

    Cheng, Hongyuan; Friis, Alan; Høeg Hansen, Jonas; Tolderlund Rasmussen, Hanne

    2010-01-01

    Effects of extrusion parameters and raw materials on extrudate expansion are respectively investigated in a twin-screw extruder and a single-screw extruder extrusion cooking experiments for fish feed, wheat, and oat & wheat mixture processing. A new phenomenological model is proposed to correlated extrudate bulk density, extrusion parameters and raw material changes based on the experimental results. The average absolute deviation (AAD) of the correlation is 2.2% for fish feed extrusion in th...

  18. Reuse of Hydrotreating Spent Catalyst

    International Nuclear Information System (INIS)

    All hydro treating catalysts used in petroleum refining processes gradually lose activity through coking, poisoning by metal, sulfur or halides or lose surface area from sintering at high process temperatures. Waste hydrotreating catalyst, which have been used in re-refining of waste lube oil at Alexandria Petroleum Company (after 5 years lifetime) compared with the same fresh catalyst were used in the present work. Studies are conducted on partial extraction of the active metals of spent catalyst (Mo and Ni) using three leaching solvents,4% oxidized oxalic acid, 10% aqueous sodium hydroxide and 10% citric acid. The leaching experiments are conducting on the de coked extrude [un crushed] spent catalyst samples. These steps are carried out in order to rejuvenate the spent catalyst to be reused in other reactions. The results indicated that 4% oxidized oxalic acid leaching solution gave total metal removal 45.6 for de coked catalyst samples while NaOH gave 35% and citric acid gave 31.9 % The oxidized leaching agent was the most efficient leaching solvent to facilitate the metal removal, and the rejuvenated catalyst was characterized by the unchanged crystalline phase The rejuvenated catalyst was applied for hydrodesulfurization (HDS) of vacuum gas oil as a feedstock, under different hydrogen pressure 20-80 bar in order to compare its HDS activity

  19. Interface Properties in Extruded FRC-Materials

    DEFF Research Database (Denmark)

    Stang, Henrik

    1997-01-01

    In a research and development project recently carried out at Department of Structural Engineering and Materials, Technical University of Denmark a new extrusion process for HPFRCC-materials was demonstrated.It is shown that superior interfacial properties are obtained in a polypropylene fiber...... reinforced cementitious material extruded by the developed process. It is further more shown that the fiber-matrix bond is highly dependent on the relative slip at the interface and a bond-slip relationship is suggested for the extruded material. The observed very high fiber-matrix bond is explained by the...... densification of the interfacial matrix material which has taken place during the consolidation process and which can be observed in the thin-section analysis....

  20. Residual stress distribution in extruded polypropylene pipes

    Czech Academy of Sciences Publication Activity Database

    Poduška, Jan; Kučera, J.; Hutař, Pavel; Ševčík, Martin; Křivánek, J.; Sadílek, J.; Náhlík, Luboš

    2014-01-01

    Roč. 2014, č. 40 (2014), s. 88-98. ISSN 0142-9418 R&D Projects: GA ČR(CZ) GAP108/12/1560 Institutional support: RVO:68081723 Keywords : polypropylene * extruded polymer pipe * residual stress * curved beam methodology * numerical simulations Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 2.240, year: 2014 http://www.sciencedirect.com/science/article/pii/S0142941814001809

  1. Hydrodynamic narrowing of tubes extruded from cells

    OpenAIRE

    Brochard-Wyart, F.; Borghi, N.; Cuvelier, D.; Nassoy, P.

    2006-01-01

    We discuss the pulling force f required to extrude a lipid tube from a living cell as a function of the extrusion velocity L̇. The main feature is membrane friction on the cytoskeleton. As recently observed for neutrophils, the tether force exhibits a “shear thinning” response over a large range of pulling velocities, which was previously interpreted by assuming viscoelastic flows of the sliding membrane. Here, we propose an alternative explanation based on purely Newtonian flow: The diameter...

  2. Soja integral processada (fermentada e extrusada e farelo de soja em substituição ao leite em pó em dieta de leitões desmamados aos 14 dias de idade Whole processed (fermented and extruded soybean and soybean meal in replacement of dried milk in diet of piglets weaned at 14 days of age

    Directory of Open Access Journals (Sweden)

    José Luis Soares

    2000-08-01

    Full Text Available O experimento foi realizado para avaliar o efeito da utilização de soja integral fermentada (SIF, soja integral extrusada (SIE e farelo de soja (FS, em substituição ao leite em pó (LP da dieta, sobre desempenho e alterações morfológicas do sistema digestivo de leitões dos 14 aos 35 dias e dos 14 aos 56 dias e o seu efeito residual dos 36 aos 56 dias de idade. Foram utilizados 96 leitões machos, mestiços (Landrace x Large White, desmamados aos 14 dias de idade, em delineamento inteiramente casualizado com quatro tratamentos, quatro repetições e seis animais por unidade experimental. A fonte de proteína influenciou o desempenho dos leitões dos 14 aos 35 e dos 14 aos 56 dias de idade. Os animais que receberam dieta com LP apresentaram maior ganho de peso nas três primeiras semanas após o desmame e no período total. No entanto, no período de 36 aos 56 dias, não se observou influência dos tratamentos sobre o desempenho dos animais. Verificou-se efeito da fonte de proteína na altura de vilosidade (AV, na relação vilosidade: cripta dos leitões abatidos aos 21 dias de idade e na AV dos animais abatidos com 35 dias de idade. Os animais que receberam dieta com LP apresentaram maior AV que os dos demais tratamentos. Concluiu-se que o LP pode ser substituído pela SIE e pelo FS nas dietas de leitões desmamados aos 14 dias de idade e os altos níveis de fatores antitripsina na SIF comprometeram os resultados.The experiment was carried out to evaluate the effect of the use of whole fermented soybean (WFS, whole extruded soybean (WES and soybean meal (SBM in replacement to the dried milk (MD of the diet on the performance, feed intake and morphological alterations on the digestive system of piglets from 14 to 35 day and from 14 to 56 days, and its residual effects from 36 to 56 days of age. Ninety-six crossbreed (Landrace x Large White piglets weaned at 14 days of age were allotted to a completely randomized experimental design with

  3. Extrudable explosives. Quarterly report, October--December, 1971

    Energy Technology Data Exchange (ETDEWEB)

    Warren, T.W.; Irion, C.E.

    1972-12-31

    Several extrudable HE formulations using, principally, HNAB as the explosive component were examined in efforts to develop an extrudable composition more temperature-resistant than Extex. It is shown that extrudability is dependent upon particle character, wetting of the binder compound, roll-milling technique and the addition of fine metallic oxides to improve flow properties, while detonability is dependent upon explosive concentration, a hard cure, and the shock parameters of the confining media.

  4. Preferred orientations in extruded nickel and iron aluminides

    Science.gov (United States)

    Khadkikar, P. S.; Michal, G. M.; Vedula, K.

    1990-01-01

    Preferred orientations in both powder-extruded and cast and extruded binary NiAl (≃45 at. pet Al), FeAl (≃40 at. pet Al), and Ni3Al (≃24 at. pet Al) have been characterized by plotting inverse pole figures. The preferred orientation, [111], was observed along the extrusion direction in both powder-extruded and cast and extruded NiAl. Powder-extruded FeAl also exhibited [111] as the preferred orientation in the as-extruded condition. However, [110] was observed to be the preferred orientation in the cast and extruded FeAl and was replaced by a [211] orientation preference upon annealing. Annealing did not change the preferred orientations in NiAl or in powder-extruded FeAl. In contrast to the B2 NiAl and FeAl alloys, the Ll2 Ni3Al alloy exhibited nearly random orientations with only a minor preference for a [111] orientation in the as-extruded condition.

  5. Extrusion of electrode material by liquid injection into extruder barrel

    Science.gov (United States)

    Keller, D.G.; Giovannoni, R.T.; MacFadden, K.O.

    1998-03-10

    An electrode sheet product is formed using an extruder having a feed throat and a downstream section by separately mixing an active electrode material and a solid polymer electrolyte composition that contains lithium salt. The active electrode material is fed into the feed throat of the extruder, while a portion of at least one fluid component of the solid polymer electrolyte composition is introduced to the downstream section. The active electrode material and the solid polymer electrolyte composition are compounded in a downstream end of the extruder. The extruded sheets, adhered to current collectors, can be formed into battery cells. 1 fig.

  6. Extruded plastic counters with WLS fiber readout

    CERN Document Server

    Kudenko, Yu G; Mayatski, V A; Mineev, O V; Yershov, N V

    2001-01-01

    Extruded plastic scintillation counters with WLS fiber readout are described. For a 7 mm thick counter with 4.3 m long double-clad fibers spaced at 7 mm a light yield of 18.7 photoelectrons/MeV and a time resolution of 0.71 ns (sigma) were obtained. A prototype photon veto module consisting of 10 layers of 7 mm thick grooved plastic slabs interleaved with 1 mm lead sheets was also tested, which yielded 122 photoelectrons per minimum ionizing particle and time resolution of 360 ps.

  7. Thermal aging effect in oxi-reduction properties and catalytic activity of CZ and Pd-CZ catalyst; O efeito da desativacao termica nas propriedades oxirredutoras e na atividade catalitica de catalisadores CZ e Pd-CZ

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Daniela Cruz Damasceno da; Zotin, Fatima Maria Zanon, E-mail: fmzzotin@gmail.com [Departamento de Operacoes e Projetos Industriais, Instituto de Quimica, Universidade do Estado do Rio de Janeiro, RJ (Brazil); Neumann, Reiner [Coordenacao de Analises Minerais, Centro de Tecnologia Mineral, Rio de Janeiro, RJ (Brazil); Hori, Carla Eponina [Faculdade de Engenharia Quimica, Universidade Federal de Uberlandia, MG (Brazil); Cardoso, Mauri Jose Baldini [Centro de Pesquisas e Desenvolvimento Leopoldo Americo Miguez de Melo - PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Automotive catalyst, using in Brazil since 1992, is a essential technology for vehicular emissions control. Noble metals are the active phase of these catalysts, and cerium zirconium mixed oxides (CZ), responsible for the oxygen storage capacity (OSC), one of the most important aspect for the operational performance of the catalyst. In this context, the oxireduction properties analysis of CZ and Pd/CZ (palladium supported in CZ) system are the objective of this study, as well as, the impact of the thermal aging in the OSC. Aging consisted of treatments at 900 or 1200 degree C, for 12 or 36 h, in oxidizing condition. (author)

  8. Impeded solid state reactions and transformations in ceramic catalysts supports and catalysts

    Directory of Open Access Journals (Sweden)

    Ernő E. Kiss

    2012-12-01

    Full Text Available Impeded chemical reactions and impeded polymorphous transformation in materials are discussed, as desired effects, for stabilization of ceramic catalyst supports and ceramic based catalysts. This paper gives a short overview about the possibilities of slowing down the aging processes in ceramic catalyst supports and catalysts. Special attention is given to alumina and titania based catalysts.

  9. Study on profile measurement of extruding tire tread by laser

    Science.gov (United States)

    Wang, LiangCai; Zhang, Wanping; Zhu, Weihu

    1996-10-01

    This paper presents a new 2D measuring system-profile measurement of extruding tire tread by laser. It includes the thickness measurement of extruding tire tread by laser and the width measurement of extruding tire tread using Moire Fringe. The system has been applied to process line of extruding tire tread. Two measuring results have been obtained. One is a standard profile picture of extruding tire tread including seven measuring values. Another one is a series of thickness and width values. When the scanning speed < 100mm/sec and total width < 800mm. The measuring errors of width < +/- 0.5mm. While the thickness range is < 40mm. The measuring errors of thickness < +/- 0.1mm.

  10. Carbon coated (carbonous) catalyst in ebullated bed reactor for production of oxygenated chemicals from syngas/CO2

    International Nuclear Information System (INIS)

    This report summarizes the work completed under DOE's Support of Advanced Fuel Research program, Contract No. DE-FG26-99FT40681. The contract period was October 2000 through September 2002. This R and D program investigated the modification of the mechanical strength of catalyst extrudates using Hydrocarbon Technologies, Inc. (HTI) carbon-coated catalyst technology so that the ebullated bed technology can be utilized to produce valuable oxygenated chemicals from syngas/CO2 efficiently and economically. Exothermic chemical reactions benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. The carbon-coated extrudates prepared using these procedures had sufficient attrition resistance and surface area for use in ebullated bed operation. The low cost of carbon coating makes the carbon-coated catalysts highly competitive in the market of catalyst extrudates

  11. Endoscopic Treatment of an extruded gastric band

    International Nuclear Information System (INIS)

    We present the case of a patient in whom a gastric band was placed for the treatment of morbid obesity with good results of loss of weight. One year after the procedure the gastric band started to be extruded into the stomach and this was almost total at 26 months. At this time the band was held only by a small tissue bridge. We did two endoscopic procedures to extract the band. In the first one the tissue bridge was cut using the duodenoscope for a better vision and handling and a needle knife papilotome. The band could not be extracted at the time because it continued to be fixed by the connector to the subcutaneous reservoir. The reservoir had been previously removed. One week later in a second procedure the band was cut using a monofilament biliary wire guide and lithotriptor. Then the band could be extracted easily. We describe the procedures, the difficulties we had and how we resolved them

  12. A Novel cooked extruded lentils analog: physical and chemical properties

    OpenAIRE

    Abu-Ghoush, Mahmoud; Alavi, Sajid; Al-Shathri, Abdulaziz

    2014-01-01

    Developing an extruded lentil analog is our aim. Lentil analog with six formulations were produced using a pilot-scale single (SS) and twin screw (TS) extruders. Texture analysis of lentil analogs prepared for consumption revealed that the products formulated with 60:40 and 70:30 soy: wheat ratios exhibited a significantly higher hardness, adhesiveness and lower springiness as compared to all other treatments. Differential Scanning Calorimeter (DSC) results indicated that all starches in dry ...

  13. Microstructure and mechanical properties of extruded Mg-8Gd-2Y-1Nd-0.3Zn-0.6Zr alloy

    International Nuclear Information System (INIS)

    Highlights: → The extruded alloy rod exhibits a weak basal texture. → Tension-compression yield asymmetry varies with increasing temperature. → Yield asymmetry is influenced by the texture at room temperature. → With increasing temperature it is affected by solute atom cluster or precipitate. - Abstract: The microstructure and mechanical properties of extruded Mg-8Gd-2Y-1Nd-0.3Zn-0.6Zr alloy rods were investigated. The as-extruded alloy exhibits a weak basal texture that the {0 0 0 1} basal planes in most grains are distributed parallel to the extrusion direction. The strength of the peak-aged alloy is greatly improved due to the fine β' precipitates. Tension-compression asymmetry is observed in both the as-extruded and peak-aged alloys. The asymmetry at room temperature is connected with the texture which induces large difference in twinning generation between tension and compression. While increasing the test temperatures, the activation of twinning is suppressed, but the mechanical asymmetry still exists. For the as-extruded alloy it is related to the presence of dynamic strain ageing or dynamic precipitation during deformation; and for the peak-aged alloy it is associated with the β' precipitates.

  14. Effect of heat treatment on microstructure and properties of hot-extruded nickel-aluminum bronze

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effect of heat treatment on the microstructure and properties of a hot-extruded nickel-aluminum bronze was investigated. Experimental materials were heat treated through different processes, including quenching, normalizing, aging and annealing, and their microstructure, corrosion resistance and mechanical properties were characterized. It is found that quenching causes all β phase transformed into β' phase, however, normalizing causes β phase transformed into β', α and κ phases. When the quenched sample is aged, fine κ phase is precipitated from the as-quenched microstructure of β' phase. Annealing causes the transformation of β' into a and κ phases. The results of mechanical property tests show that quenching, normalizing and aging improve the tensile strength and hardness of the experimental material, with a corresponding fall in elongation. Annealing raises the elongation but reduces the tensile strength and hardness. Furthermore, corrosion resistance of nickel-aluminum bronze ranks from worse to better in the following order: aged, quenched, normalized, hot-extruded and annealed. However, with the exposure time of corrosion test increasing, the difference of average corrosion rate between those nickel-aluminum bronzes tums small.

  15. Bio rapid prototyping by extruding/aspirating/refilling thermoreversible hydrogel

    Energy Technology Data Exchange (ETDEWEB)

    Iwami, K; Noda, T; Ishida, K; Umeda, N [Department of Mechanical Systems and Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan); Morishima, K [Department of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan); Nakamura, M, E-mail: k_iwami@cc.tuat.ac.j [Department of Life Sciences and Bioengineering, University of Toyama, 3190 Gofuku, Toyama, 930-8555 (Japan)

    2010-03-15

    This paper reports a method for rapid prototyping of cell tissues, which is based on a system that extrudes, aspirates and refills a mixture of cells and thermoreversible hydrogel as a scaffold. In the extruding mode, a cell-mixed scaffold solution in the sol state is extruded from a cooled micronozzle into a temperature-controlled substrate, which keeps the scaffold in the gel state. In the aspiration mode, the opposite process is performed by Bernoulli suction. In the refilling mode, the solution is extruded into a groove created in the aspiration mode. The minimum width of extruded hydrogel pattern is 114 +- 15 mum by employing a nozzle of diameter 100 mum, and that of aspirated groove was 355 +- 10 mum using a 500 mum-diameter nozzle. Gum arabic is mixed with the scaffold solution to avoid peeling-off of the gel pattern from the substrate. Patterning of Sf-9 cell tissue is demonstrated, and the stability of the patterned cell is investigated. This system offers a procedure for rapid prototyping and local modification of cell scaffolds for tissue engineering.

  16. Extruder system and method for treatment of a gaseous medium

    Energy Technology Data Exchange (ETDEWEB)

    Silvi, Norberto; Perry, Robert James; Singh, Surinder Prabhjot; Balch, Gary Stephen; Westendorf, Tiffany Elizabeth Pinard

    2016-04-05

    A system for treatment of a gaseous medium, comprises an extruder having a barrel. The extruder further comprises a first inlet port, a second inlet port, and a plurality of outlet ports coupled to the barrel. The first inlet port is configured for feeding a lean sorbent, the second inlet port is configured for feeding a gaseous medium, and the plurality of outlet ports are configured for releasing a plurality of components removed from the gaseous medium. Further, the extruder comprises a plurality of helical elements coupled to a plurality of kneading elements, mounted on a shaft, and disposed within the barrel. The barrel and the plurality of helical and kneading elements together form an absorption unit and a desorption unit. The first and second inlet ports are formed in the absorption unit and the plurality of outlet ports are formed in the absorption and desorption units.

  17. Analysis of the Retained Gas Sample (RGS) Extruder Assembly

    International Nuclear Information System (INIS)

    In order for the Retained Gas Sample (RGS) Extruder Assembly to be safely used it was determined by the cognizant engineer that analysis was necessary. The use of the finite-element analysis (FEA) progarm COSMOS/M version 1.71 permitted a quick, easy, and detailed stress analysis of the RGS Extruder Assembly. The FEA model is a three dimensional model using the SHELL4T element type. From the results of the FEA, the cognizant engineer determined that the RGS extruder would be rated at 10,000 lbf and load tested to 12,000 lbf. The respective input and output files for the model are EXTR02.GFM and EXTR02.OUT and can be found on the attached tape

  18. Studies on positive conveying in helically channeled single screw extruders

    OpenAIRE

    Pan, L.; M. Y. Jia; Jin, Z. M.; K. J. Wang; Xue, P

    2012-01-01

    A solids conveying theory called double-flight driving theory was proposed for helically channeled single screw extruders. In the extruder, screw channel rotates against static barrel channel, which behaves as cooperative embedded twin-screws for the positive conveying. They turn as two parallel arc plates, between which an arc-plate solid-plug was assumed. By analyzing the forces on the solid-plug in the barrel channel and screw channel, the boundary conditions when the solid-plug is waived ...

  19. Characterization of modified 9 Cr-1 Mo steel extruded pipe

    International Nuclear Information System (INIS)

    The fabrication of hot-extruded pipe of modified 9 Cr-1 Mo steel at Cameron Iron Works is described. The report also deals with the tempering response; tensile, Charpy impact, and creep properties; and microstructure of the hot-extruded pipe. The tensile properties of the pipe are compared with the average and average -1.65 standard error of estimate curves for various product forms of several commercial heats of this alloy. The creep-rupture properties are compared with the average curve for various product forms of the commercial heats

  20. PREDICTING THE DURABILITY OF EXTRUDED FOAM POLYSTYRENE IN ROAD STRUCTURES

    Directory of Open Access Journals (Sweden)

    V. P. Yartsev

    Full Text Available Statement of the problem. It is possible to improve working conditions of road pavement and to use it more efficiently by regulating water-thermal conditions of the subgrade thereby reducing humidity in the design period and mitigating its seasonal changes.Results and conclusions. It is suggested to use extruded foam polystyrene as a heating layer. The thermal fluctuation approach was applied to failure and deformation processes. Physical constants for the analytical description of these processes at varying temperatures and stresses are calculated. The technique for determining acting stresses and temperatures was described. The prediction of the durability of extruded foam polystyrene in road structure is presented

  1. Effect of Zn on the microstructure evolution of extruded Mg–3Nd (–Zn)–Zr (wt.%) alloys

    International Nuclear Information System (INIS)

    Highlights: ► Age-hardening effect of as-extruded Mg–3Nd (–Zn)–Zr alloys decreases with Zn. ► Increasing Zn, β″ in aged alloys decrease while basal plates increases. ► Aged NZ30K behave the highest UTS due to co-existence of basal and prism plates. ► The yield phenomena are connected to the random texture as well as dislocations. - Abstract: This paper presents the results of a transmission electron microscopy study of the microstructure of extruded Mg–Nd–Zn alloys that exhibit improvement in strength, making them potential candidates for bumper beam applications. Three sets of extruded rods with 0%, 0.2% and 0.5% Zn addition are prepared to examine the effect of Zn on the precipitates in the as-extruded and aged condition. At least five different precipitate phases with different structures, morphologies and distributions were identified and correlated with the mechanical properties. Zn is seen to have no effect on the precipitation sequence of Nd-rich phases but seems to control the growth of those phases. It is found that small amount of Zn can lead to drastic changes in the nature of the precipitate phase due to the strong affinity between Zn and Nd in the alloy to form Mg–Nd–Zn intermetallics, affecting the strength and ductility. Control of both the Nd and Zn content are necessary to take advantage of the “rare earth texture” induced by Nd to improve ductility and precipitation strengthening by the Mg–Nd–Zn intermetallics when Zn is present.

  2. Effect of Zn on the microstructure evolution of extruded Mg-3Nd (-Zn)-Zr (wt.%) alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ma Lan [National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Mishra, Raja K.; Balogh, Michael P. [General Motors Research and Development Center, Warren, MI 48090 (United States); Peng Liming, E-mail: plm616@sjtu.edu.cn [National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University,800 Dongchuan Road, Shanghai 200240 (China); Luo, Alan A.; Sachdev, Anil K. [General Motors Research and Development Center, Warren, MI 48090 (United States); Ding Wenjiang [National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University,800 Dongchuan Road, Shanghai 200240 (China)

    2012-05-01

    Highlights: Black-Right-Pointing-Pointer Age-hardening effect of as-extruded Mg-3Nd (-Zn)-Zr alloys decreases with Zn. Black-Right-Pointing-Pointer Increasing Zn, {beta} Double-Prime in aged alloys decrease while basal plates increases. Black-Right-Pointing-Pointer Aged NZ30K behave the highest UTS due to co-existence of basal and prism plates. Black-Right-Pointing-Pointer The yield phenomena are connected to the random texture as well as dislocations. - Abstract: This paper presents the results of a transmission electron microscopy study of the microstructure of extruded Mg-Nd-Zn alloys that exhibit improvement in strength, making them potential candidates for bumper beam applications. Three sets of extruded rods with 0%, 0.2% and 0.5% Zn addition are prepared to examine the effect of Zn on the precipitates in the as-extruded and aged condition. At least five different precipitate phases with different structures, morphologies and distributions were identified and correlated with the mechanical properties. Zn is seen to have no effect on the precipitation sequence of Nd-rich phases but seems to control the growth of those phases. It is found that small amount of Zn can lead to drastic changes in the nature of the precipitate phase due to the strong affinity between Zn and Nd in the alloy to form Mg-Nd-Zn intermetallics, affecting the strength and ductility. Control of both the Nd and Zn content are necessary to take advantage of the 'rare earth texture' induced by Nd to improve ductility and precipitation strengthening by the Mg-Nd-Zn intermetallics when Zn is present.

  3. Development of a low-cost extruded scintillator with co-extruded reflector for the MINOS experiment

    International Nuclear Information System (INIS)

    The MINOS experiment is a long-baseline, neutrino-oscillation experiment. In total, 28,000 m2 of scintillator is needed for the experiment. This is almost 300 tons of finished scintillator. The solution has been the development of an extruded scintillator with a 2-mm deep grove in the upper surface for a wavelength-shifting fiber and a co-extruded TiO2 coating as a reflector. The TiO2 coating also allows the scintillator to be directly epoxied into panels. Production and quality control techniques are presented

  4. A numbering algorithm for finite element on extruded meshes which avoids the unstructured mesh penalty

    OpenAIRE

    Bercea, Gheorghe-Teodor; McRae, Andrew T. T.; Ham, David A.; Mitchell, Lawrence; Rathgeber, Florian; Nardi, Luigi; Luporini, Fabio; Kelly, Paul H. J.

    2016-01-01

    We present a generic algorithm for numbering and then efficiently iterating over the data values attached to an extruded mesh. An extruded mesh is formed by replicating an existing mesh, assumed to be unstructured, to form layers of prismatic cells. Applications of extruded meshes include, but are not limited to, the representation of 3D high aspect ratio domains employed by geophysical finite element simulations. These meshes are structured in the extruded direction. The algorithm presented ...

  5. Effect of process and compound formulation variables on properties of extruded EPDM foam

    OpenAIRE

    Chonlada K. Lewis; Bunreang Misaen; Sarote Changchum

    1999-01-01

    The effects of extruded EPDM foam tube compound formulations and process conditions on foam properties were investigated. The objective was to obtain a fine close cell structure with low density foam indication better insulation properties. A cold feed extruder was used to prepare extruded tubes where foaming and vulcanizing took place in a circulationg hot air oven. Five grades of EPDM rubber base were compounded with a formula that gave good surface quality extrudates. The viscosity and die...

  6. Homogeneous catalysts

    CERN Document Server

    Chadwick, John C; Freixa, Zoraida; van Leeuwen, Piet W N M

    2011-01-01

    This first book to illuminate this important aspect of chemical synthesis improves the lifetime of catalysts, thus reducing material and saving energy, costs and waste.The international panel of expert authors describes the studies that have been conducted concerning the way homogeneous catalysts decompose, and the differences between homogeneous and heterogeneous catalysts. The result is a ready reference for organic, catalytic, polymer and complex chemists, as well as those working in industry and with/on organometallics.

  7. Part II: Oxidative Thermal Aging of Pd/Al2O3 and Pd/CexOy-ZrO2 in Automotive Three Way Catalysts: The Effects of Fuel Shutoff and Attempted Fuel Rich Regeneration

    Directory of Open Access Journals (Sweden)

    Qinghe Zheng

    2015-10-01

    Full Text Available The Pd component in the automotive three way catalyst (TWC experiences deactivation during fuel shutoff, a process employed by automobile companies for enhancing fuel economy when the vehicle is coasting downhill. The process exposes the TWC to a severe oxidative aging environment with the flow of hot (800 °C–1050 °C air. Simulated fuel shutoff aging at 1050 °C leads to Pd metal sintering, the main cause of irreversible deactivation of 3% Pd/Al2O3 and 3% Pd/CexOy-ZrO2 (CZO as model catalysts. The effect on the Rh component was presented in our companion paper Part I. Moderate support sintering and Pd-CexOy interactions were also experienced upon aging, but had a minimal effect on the catalyst activity losses. Cooling in air, following aging, was not able to reverse the metallic Pd sintering by re-dispersing to PdO. Unlike the aged Rh-TWCs (Part I, reduction via in situ steam reforming (SR of exhaust HCs was not effective in reversing the deactivation of aged Pd/Al2O3, but did show a slight recovery of the Pd activity when CZO was the carrier. The Pd+/Pd0 and Ce3+/Ce4+ couples in Pd/CZO are reported to promote the catalytic SR by improving the redox efficiency during the regeneration, while no such promoting effect was observed for Pd/Al2O3. A suggestion is made for improving the catalyst performance.

  8. 时效制度对挤压Al-6.2Zn-2.3Mg-2.3Cu铝合金电化学腐蚀性能的影响%Effect of ageing process on electrochemical corrosion property of extruded Al-6.2Zn-2.3Mg-2.3Cu aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    孙擎擎; 董朋轩; 孙睿吉; 陈启元; 陈康华

    2015-01-01

    The electrochemical corrosion behavior of extruded Al-6.2Zn-2.3Mg-2.3Cu Al alloy was investigated. The open circuit potential (OCP), cyclic polarization curve and electrochemical impedance spectroscopy (EIS) were performed in 3.5% (mass fraction) NaCl and 10 mmol/L NaCl+0.1 mol/L Na2SO4 solutions. The results show that the resistance to localized corrosion of various ageing processes according to decreasing order is T76+T6, T76, T77, T6, as deduced from electrochemical parameters, such as OCP, corrosion potential, repassivation potential, pitting potential, pitting transition potential, linear polarization resistance, corrosion current density and charge transfer resistance of EIS. Corrosion morphologies indicate that pitting corrosion is the main corrosion form for Al-6.2Zn-2.3Mg-2.3Cu alloy in the solution of 10 mmol/L NaCl+0.1 mol/L Na2SO4, which can be terrified by the occurrence of pitting potential and pitting transition potential in its cyclic polarization curves. Being different from 10 mmol/L NaCl+0.1 mol/L Na2SO4, the pitting corrosion and intergranular corrosion (IGC) can be observed in 3.5%NaCl solution.φb, (φb−φcorr), and (φcorr−φrep) were used as criteria to evaluate the localized corrosion. Additionally, the influence of ageing process on the hardness and conductivity was also discussed. T76+T6 shows the least decline of hardness comparing to T6 and the best corrosive resistance amongst the four ageing processes.%采用开路电位、循环极化曲线、电化学阻抗谱及腐蚀形貌表征等研究不同时效制度下 Al-6.2Zn-2.3Mg-2.3Cu铝合金分别在3.5%NaCl(质量分数)以及10 mmol/L NaCl+0.1mol/L Na2SO4溶液中的电化学腐蚀行为。结果表明:4种时效制度处理后,挤压铝合金耐局部腐蚀能力由大到小的顺序依次为 T76+T6、T76、T77、T6。试样在10 mmol/L NaCl+0.1mol/L Na2SO4溶液中主要发生点蚀,从循环阳极极化曲线上可以观察到明显的点蚀电

  9. Analysis of operation records. Evaluation of event sequences in extruder

    International Nuclear Information System (INIS)

    All result of chemical analysis and operators observation suggest non-chemical mechanism raised the filing temperature of the bituminized product at the incident. We, Tokai reprocessing plant safety evaluation and analysis team, performed the experiment using laboratory scale extruder and viscosity measurement to explain the high temperature of mixture. The result of the experiment using laboratory scale extruder showed that the phenomena of salt enrichment and salt accumulation occurred and they raised mixture temperature at the decreased feed rate. These phenomena depend on the feed rate and they have large contribution of heat transportation and rise of operational torque due to the friction between screw and mixture. Based on the experiment result and all information, we investigated the operation procedure, operational records and machine arrangement to try to explain the behavior of the mixture in the extruder. Judging from each torque and temperature behavior, we succeeded in explaining a sequential behavior in the incident. It is estimated that mixture temperature was raised by physical heat generation in the extruder and this report explains each operation, investigated result and estimated event sequences. (author)

  10. Studies on positive conveying in helically channeled single screw extruders

    Directory of Open Access Journals (Sweden)

    L. Pan

    2012-07-01

    Full Text Available A solids conveying theory called double-flight driving theory was proposed for helically channeled single screw extruders. In the extruder, screw channel rotates against static barrel channel, which behaves as cooperative embedded twin-screws for the positive conveying. They turn as two parallel arc plates, between which an arc-plate solid-plug was assumed. By analyzing the forces on the solid-plug in the barrel channel and screw channel, the boundary conditions when the solid-plug is waived of being cut off on barrel wall, were found to have the capacity of the positive conveying. Experimental data were obtained using a specially designed extruder with a helically channeled barrel in the feeding zone and a pressure-adjustable die. The effects of the barrel channel geometry and friction coefficients on the conveying mechanism were presented and compared with the experimental results. The simulations showed that the positive conveying could be achieved after optimizing extruder designs. Compared with the traditional design with the friction-drag conveying, the throughput is higher while screw torque and energy consumption are decreased. Besides, the design criteria of the barrel channel were also discussed.

  11. PHYSICAL PROPERTIES OF EXTRUDED AND INJECTION MOLDED CORN GLUTEN MEAL

    Science.gov (United States)

    This study was performed to investigate the compounding of corn gluten meal (CGM) and decanoic acid and to evaluate their mechanical properties. The mixture of CGM and 30% decanoic acid was compounded in a twin screw extruder, followed by injection molding. Scanning electron microscopy (SEM), tens...

  12. Radiation induced grafting of acrylic acid onto extruded polystyrene surface

    International Nuclear Information System (INIS)

    Polystyrene materials with good solubility in liquid scintillation cocktails are used to wipe off different types of surfaces in order to determine the tritium removable contamination with the help of a liquid scintillation counter. This paper analyses hydrophilic surface modifications by radiation induced grafting of acrylic groups onto extruded polystyrene plates. Two grafting methods were used: (a) exposure of extruded polystyrene plates, immersed in aqueous acrylic acid solution, to a gamma radiation of a Co-60 source, and (b) exposure of extruded polystyrene plates to a Co-60 source, followed by the immersion of extruded polystyrene plates in aqueous acrylic acid solution. The grafting of acrylic was proved by IR spectrometry and by radiometric methods using acrylic acid labelled with tritium. - Highlights: ► Polystyrene (PS) is used to determine the removable surface contamination (RSC). ► RSC factor may be increased by PS surface modification. ► PS surface was modified by acrylic acid grafting using γ radiation 60Co source. ► Acrylic fragments insertion was determined by IR, and radiometric. ► Grafted PS discs increase RSC factor in the case of tritium contamination.

  13. 78 FR 58520 - Extruded Rubber Thread From Malaysia; Notice of Amended Final Results of Antidumping Duty...

    Science.gov (United States)

    2013-09-24

    ... International Trade Administration Extruded Rubber Thread From Malaysia; Notice of Amended Final Results of... review of the antidumping duty order on extruded rubber thread from Malaysia.\\1\\ The period of review (POR) is October 1, 1995, through September 30, 1996. \\1\\ See Extruded Rubber Thread From...

  14. A New Extrudable Form of Hypromellose: AFFINISOL™ HPMC HME.

    Science.gov (United States)

    Huang, Siyuan; O'Donnell, Kevin P; Keen, Justin M; Rickard, Mark A; McGinity, James W; Williams, Robert O

    2016-02-01

    Hypromellose is a hydrophilic polymer widely used in immediate- and modified-release oral pharmaceutical dosage forms. However, currently available grades of hypromellose are difficult, if not impossible, to process by hot melt extrusion (HME) because of their high glass transition temperature, high melt viscosity, and low degradation temperature. To overcome these challenges, a modified grade of hypromellose, AFFINISOL™ HPMC HME, was recently introduced. It has a significantly lower glass transition temperature and melt viscosity as compared to other available grades of hypromellose. The objective of this paper is to assess the extrudability and performance of AFFINISOL™ HPMC HME (100LV and 4M) as compared to other widely used polymers in HME, including HPMC 2910 100cP (the currently available hypromellose), Soluplus®, Kollidon® VA 64, and EUDRAGIT® E PO. Formulations containing polymer and carbamazepine (CBZ) were extruded on a co-rotating 16-mm twin-screw extruder, and the effect of temperature, screw speed, and feed rate was investigated. The performance of the solid dispersions was evaluated based on Flory-Huggins modeling and characterized by differential scanning calorimetry (DSC), X-ray powder diffraction (XRD), Raman spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and dissolution. All formulations extruded well except for HPMC 2910 100cP, which resulted in over-torqueing the extruder (machine overloading because the motor cannot provide efficient energy to rotate the shaft). Among the HME extrudates, only the EUDRAGIT® E PO formulation was crystalline as confirmed by DSC, XRD, and Raman, which agreed with predictions from Flory-Huggins modeling. Dissolution testing was conducted under both sink and non-sink conditions. Sink dissolution testing in neutral media revealed that amorphous CBZ in the HME extrudates completely dissolved within 15 min, which was much more rapid than the time for complete dissolution of bulk CBZ (60 min) and

  15. Processing and characterization of extruded zein-based biodegradable films

    Science.gov (United States)

    Wang, Ying

    The objectives of this study were to prepare biodegradable zein films by extrusion processing and to evaluate relevant physical properties of resulting films with respect to their potential as packaging materials. The manufacture of protein-based packaging films by extrusion has remained a challenge. In this study, a zein resin was prepared by combining zein and oleic acid. This resin was formed into films by blown extrusion at the bench-top scale. Resin moisture content and extruder barrel temperature profile were identified as major parameters controlling the process. The optimum temperature of the blowing head was determined to be 40--45°C, while optimum moisture at film collection was 14--15%. Physico-chemical properties of the extruded products were characterized. Extruded products exhibited plastic behavior and ductility. Morphology characterization by SEM showed micro voids in extruded zein sheets, caused by entrapped air bubbles or water droplets. DSC characterization showed that zein was effectively plasticized by oleic acid as evidenced by the lowered glass transition temperature of zein films. X-ray scattering was used to investigate changes in zein molecular aggregation during processing. It was observed that higher mechanical energy treatment progressively disrupted zein molecular aggregates, resulting in a more uniform distribution of individual zein molecules. With the incorporation of oleic acid as plasticizer and monoglycerides as emulsifier, zein formed structures with long-range periodicity which varied depending on the formulation and processing methods. Processing methods for film formation affected the binding of oleic acid to zein with higher mechanical energy treatment resulting in better interaction between the two components. The moisture sorption capacity of extruded zein films was reduced due to the compact morphology caused by extrusion. Plasticization with oleic acid further reduced moisture sorption of zein films. The overall

  16. Pore design of pelletised VOX/ZrO2-SO4/Sepiolite composite catalysts

    DEFF Research Database (Denmark)

    Rasmussen, Søren Birk; Due-Hansen, Johannes; Yates, Malcolm;

    2010-01-01

    The NH3-SCR activities of a series of extruded and calcined VOX/ZrO2-SO4 - sepiolite catalysts were determined. The pore structures were heavily influenced by the clay content with macropore sizes ranging from 50 to >1000 nm. Mechanical strength and SCR activity measurements suggested that 25% w/...

  17. Effect of acid catalysts and accelerated aging on the reaction of methanol with hydroxy-acetaldehyde in bio-oil

    Directory of Open Access Journals (Sweden)

    Bhattacharya, P.

    2010-05-01

    Full Text Available Bio-oil is a promising alternative source of energy produced from fast pyrolysis of biomass. Increasing the viscosity of bio-oil during storage is a major problem that can be controlled by the addition of methanol or other alcohols. This paper reports the results of our investigation of the reactions of short chain alcohols with aldehydes and acids in bio-oil. The reaction of methanol with hydroxyacetaldehyde (HA to form the acetal was catalyzed by the addition of 7 x 10-4 M strong acids such as sulfuric, hydrochloric, p-toluene sulfonic acid, and methanesulfonic acid. HA formed 2,2-dimethoxyethanol (DME, and at 60 oC the equilibrium was reached in less than one hour. Smaller amounts of DME were formed in the absence of strong acid. HA, acetaldehyde, and propanal formed their corresponding acetals when reacted with methanol, ethanol, 1-propanol or 1-butanol. Esters of acetic acid and hydroxyacetic acid were observed from reactions with these same four alcohols. Other acetals and esters were observed by GC/MS analysis of the reaction products. The results from accelerated aging experiments at 90 oC suggest that the presence of methanol slows polymerization by formation of acetals and esters from low molecular weight aldehydes and organic acids.

  18. Bimetallic Catalysts.

    Science.gov (United States)

    Sinfelt, John H.

    1985-01-01

    Chemical reaction rates can be controlled by varying composition of miniscule clusters of metal atoms. These bimetallic catalysts have had major impact on petroleum refining, where work has involved heterogeneous catalysis (reacting molecules in a phase separate from catalyst.) Experimentation involving hydrocarbon reactions, catalytic…

  19. Extrudates of starch-xanthan gum mixtures as affected by chemical agents and irradiation

    International Nuclear Information System (INIS)

    Mixtures of starch, xanthan gum and either polyvinyl alcohol, epichlorohydrin, valeric acid or adipoyl chloride were extruded. Properties of extrudates including apparent viscosity, water solubility, water absorption indices and extrudate expansion were measured for different proportions of xanthan gum, 70% amylose starch (with or without irradiation) and chemical agents. Extrusion with chemical agents and irradiation changed physical properties of both starch and xanthan gum. Expansions of extrudates were higher than that of starch. Viscosity of extrudates increased with xanthan gum concentration. The addition of 1% (w/w) polyvinyl alcohol had the greatest effect of the chemical agents. Irradiation increased the apparent viscosity of starch-xanthan gum mixtures

  20. Development of a Tritium Extruder for ITER Pellet Injection

    Energy Technology Data Exchange (ETDEWEB)

    M.J. Gouge; P.W. Fisher

    1998-09-01

    As part of the International Thermonuclear Experimental Reactor (ITER) plasma fueling development program, Oak Ridge National Laboratory (ORNL) has fabricated a pellet injection system to test the mechanical and thermal properties of extruded tritium. Hydrogenic pellets will be used in ITER to sustain the fusion power in the plasma core and may be crucial in reducing first-wall tritium inventories by a process of "isotopic fueling" in which tritium-rich pellets fuel the burning plasma core and deuterium gas fuels the edge. This repeating single-stage pneumatic pellet injector, called the Tritium-Proof-of-Principle Phase II (TPOP-II) Pellet Injector, has a piston-driven mechanical extruder and is designed to extrude and accelerate hydrogenic pellets sized for the ITER device. The TPOP-II program has the following development goals: evaluate the feasibility of extruding tritium and deuterium-tritium (D-T) mixtures for use in future pellet injection systems; determine the mechanical and thermal properties of tritium and D-T extrusions; integrate, test, and evaluate the extruder in a repeating, single-stage light gas gun that is sized for the ITER application (pellet diameter -7 to 8 mm); evaluate options for recycling propellant and extruder exhaust gas; and evaluate operability and reliability of ITER prototypical fueling systems in an environment of significant tritium inventory that requires secondary and room containment systems. In tests with deuterium feed at ORNL, up to 13 pellets per extrusion have been extruded at rates up to 1 Hz and accelerated to speeds of 1.0 to 1.1 km/s, using hydrogen propellant gas at a supply pressure of 65 bar. Initially, deuterium pellets 7.5 mm in diameter and 11 mm in length were produced-the largest cryogenic pellets produced by the fusion program to date. These pellets represent about a 10% density perturbation to ITER. Subsequently, the extruder nozzle was modified to produce pellets that are almost 7.5-mm right circular

  1. Development of an extruder-feeder biomass direct liquefaction process. Volume 2, Parts 4--8: Final report

    Energy Technology Data Exchange (ETDEWEB)

    White, D.H.; Wolf, D. [Arizona Univ., Tucson, AZ (United States). Dept. of Chemical Engineering

    1991-10-01

    As an abundant, renewable, domestic energy resource, biomass could help the United States reduce its dependence on imported oil. Biomass is the only renewable energy technology capable of addressing the national need for liquid transportation fuels. Thus, there is an incentive to develop economic conversion processes for converting biomass, including wood, into liquid fuels. Through research sponsored by the US DOE`s Biomass Thermochemical Conversion Program, the University of Arizona has developed a unique biomass direct liquefaction system. The system features a modified single-screw extruder capable of pumping solid slurries containing as high as 60 wt% wood flour in wood oil derived vacuum bottoms at pressures up to 3000 psi. The extruder-feeder has been integrated with a unique reactor by the University to form a system which offers potential for improving high pressure biomass direct liquefaction technology. The extruder-feeder acts simultaneously as both a feed preheater and a pumping device for injecting wood slurries into a high pressure reactor in the biomass liquefaction process. An experimental facility was constructed and following shakedown operations, wood crude oil was produced by mid-1985. By July 1988, a total of 57 experimental continuous biomass liquefaction runs were made using White Birch wood feedstock. Good operability was achieved at slurry feed rates up to 30 lb/hr, reactor pressures from 800 to 3000 psi and temperatures from 350{degree}C to 430{degree}C under conditions covering a range of carbon monoxide feed rates and sodium carbonate catalyst addition. Crude wood oils containing as little as 6--10 wt% residual oxygen were produced. 38 refs., 82 figs., 26 tabs.

  2. Enrichment of extruded snack products with whey protein

    OpenAIRE

    Mladen Brnčić; Sven Karlović; Tomislav Bosiljkov; Branko Tripalo; Damir Ježek; Ivana Cugelj; Valentina Obradović

    2008-01-01

    Highest share in products with whey proteins addition belongs to aromatised drinks, aromatised protein bars and various dietetic preparations. In the last few years, there is increased use of the extrusion process for production of food products. This process is, besides other things, used for obtaining directly expanded products, which are immediately packed and sent on market after mechanical and thermal treatment in extruder, or after drying for a short time. One of these food products is ...

  3. Properties of extruded xanthan-starch-clay nanocomposite films

    OpenAIRE

    Cristina de Melo; Patrícia Salomão Garcia; Maria Victória Eiras Grossmann; Fábio Yamashita; Luiz Henrique Dall'Antônia; Suzana Mali

    2011-01-01

    The aim of this work was to manufacture the biodegradable nanocomposite films by extrusion from different combinations of cassava starch, xanthan gum and nanoclays (sodium montmorillonite - MMT- Na) and to characterize them according to their microstructure, optical, mechanical and barrier properties. Films were manufactured from nine starch/xanthan/nanoclay combinations, containing glycerol as plasticizer. Scanning electron microscopy (SEM) of the starch-xanthan extruded films showed reticul...

  4. Evaluation of apically extruded debris during endodontic retreatment

    Directory of Open Access Journals (Sweden)

    Marco Antonio Hungaro Duarte

    2013-03-01

    Full Text Available Introduction: A growing interest to preserve teeth into the mouth by patients resulted in the increasing number of endodontic retreatments, and when these happen, many different types of irritants are extruded through the foramen. Objective: This study analyzed in vitro the amount of debris extruded through the foramen using four instrumentation techniques during endodontic retreatment. Material and methods: Forty mesial-buccal roots of first molars were selected, instrumented with anatomical diameter up to size #30 ISO file and then obturated with gutta-percha and grossman sealer by lateral condensation. After, they were separated and randomly allocated into four groups with 10 teeth each for the endodontic retreatment procedure: G1 – conventional technique + solvent, G2 – conventional technique without solvent, G3 – ProTaper retreatment + solvent, G4 – ProTaper retreatment without solvent. In all groups, gutta-percha in the coronal portion was removed by using size 1-3 Gates Glidden drills. All teeth were irrigated with distilled water. The debris extruded through the foramen were collected and weighed by an analytical balance. Results: Group 4 had the lowest average for material extrusion through the foramen followed by groups 2, 3 and 1. When Tukey test for statistical analysis was applied, no significant difference among groups were found (p = 0.5664. Conclusion: We conclude that all instrumentation techniques used in this study produced debris which goes beyond the foramen.

  5. Enrichment of extruded snack products with whey protein

    Directory of Open Access Journals (Sweden)

    Mladen Brnčić

    2008-08-01

    Full Text Available Highest share in products with whey proteins addition belongs to aromatised drinks, aromatised protein bars and various dietetic preparations. In the last few years, there is increased use of the extrusion process for production of food products. This process is, besides other things, used for obtaining directly expanded products, which are immediately packed and sent on market after mechanical and thermal treatment in extruder, or after drying for a short time. One of these food products is “snack” food. Snack food is made with twin corotating screw extruders, in which raw materials are submitted to high temperatures and short time, with intensive expansion and rapid pressure drop. For the production of this category of food products, basic ingredients like corn, wheat, rye and rice, with the maximum of 9 % of proteins, are used. With the development of extrusion technology, special attention is focused on the enrichment of extruded products with different types of proteins, including proteins. In this paper, review of the newest research and achievements in embedding various types of whey concentrates in snack food will be represented. This category of food products for direct consummation is constantly increasing, and addition of whey protein concentrate adds better nutritional value and increased functionality.

  6. Photo-oxidation catalysts

    Science.gov (United States)

    Pitts, J. Roland; Liu, Ping; Smith, R. Davis

    2009-07-14

    Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

  7. Energy monitoring and quality control of a single screw extruder

    International Nuclear Information System (INIS)

    Highlights: • A simple real-time energy monitoring method has been developed for polymer extruder. • The effect of process settings on energy consumption has been investigated. • A complete monitoring and control system for polymer extrusion has been developed. • A feedback control system based on fuzzy logic has been developed and validated. - Abstract: Polymer extrusion, in which a polymer is melted and conveyed to a mould or die, forms the basis of most polymer processing techniques. Extruders frequently run at non-optimised conditions and can account for 15–20% of overall process energy losses. In times of increasing energy efficiency such losses are a major concern for the industry. Product quality, which depends on the homogeneity and stability of the melt flow which in turn depends on melt temperature and screw speed, is also an issue of concern of processors. Gear pumps can be used to improve the stability of the production line, but the cost is usually high. Likewise it is possible to introduce energy meters but they also add to the capital cost of the machine. Advanced control incorporating soft sensing capabilities offers opportunities to this industry to improve both quality and energy efficiency. Due to strong correlations between the critical variables, such as the melt temperature and melt pressure, traditional decentralized PID (Proportional–Integral–Derivative) control is incapable of handling such processes if stricter product specifications are imposed or the material is changed from one batch to another. In this paper, new real-time energy monitoring methods have been introduced without the need to install power meters or develop data-driven models. The effects of process settings on energy efficiency and melt quality are then studied based on developed monitoring methods. Process variables include barrel heating temperature, water cooling temperature, and screw speed. Finally, a fuzzy logic controller is developed for a single

  8. Aging.

    Science.gov (United States)

    Park, Dong Choon; Yeo, Seung Geun

    2013-09-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  9. Modeling of low-cement extruded curb of concrete-faced rockfill dam

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ga; Zhang, Jian-Min

    2011-01-15

    Low cement extruded curb is used in most new concrete-faced rockfill dams. This study examined extruded curb interactions with the gravels and the face slab and then proposed a new model to describe it. This model has been developed on test observation and has then been validated using a two-dimensional simulation of a CFRD. This new model provides a valid simulation of the extruded curb while using far less elements than the direct simulation.

  10. Material wear and failure mode analysis of breakfast cereal extruder barrels and screw elements

    Science.gov (United States)

    Mastio, Michael Joseph, Jr.

    2005-11-01

    Nearly seventy-five years ago, the single screw extruder was introduced as a means to produce metal products. Shortly after that, the extruder found its way into the plastics industry. Today much of the world's polymer industry utilizes extruders to produce items such as soda bottles, PVC piping, and toy figurines. Given the significant economical advantages of extruders over conventional batch flow systems, extruders have also migrated into the food industry. Food applications include the meat, pet food, and cereal industries to name just a few. Cereal manufacturers utilize extruders to produce various forms of Ready-to-Eat (RTE) cereals. These cereals are made from grains such as rice, oats, wheat, and corn. The food industry has been incorrectly viewed as an extruder application requiring only minimal energy control and performance capability. This misconception has resulted in very little research in the area of material wear and failure mode analysis of breakfast cereal extruders. Breakfast cereal extruder barrels and individual screw elements are subjected to the extreme pressures and temperatures required to shear and cook the cereal ingredients, resulting in excessive material wear and catastrophic failure of these components. Therefore, this project focuses on the material wear and failure mode analysis of breakfast cereal extruder barrels and screw elements, modeled as a Discrete Time Markov Chain (DTMC) process in which historical data is used to predict future failures. Such predictive analysis will yield cost savings opportunities by providing insight into extruder maintenance scheduling and interchangeability of screw elements. In this DTMC wear analysis, four states of wear are defined and a probability transition matrix is determined based upon 24,041 hours of operational data. This probability transition matrix is used to predict when an extruder component will move to the next state of wear and/or failure. This information can be used to determine

  11. Rheological and nutritional quality of selected dehulled legumes blended rice extrudates.

    Science.gov (United States)

    Balasubramanian, S; Borah, Anjan; Singh, K K; Patil, R T

    2012-10-01

    Rheological and nutritional quality of ready-to-eat rice (Oryza sativa ) -legume viz. black gram (Vigna mungo), green gram (Vigna radiata), lentil (Lens culinaris) and peas (Pisum sativum) based extrudates were studied using low cost collet extruder. Extrudates were prepared keeping constant feed rate (25 kg/h) and moisture content (14% wb) at 0, 5, 10 and 15% legume incorporation levels. Rheological properties of porridge made of extrudate flour were evaluated using Rapid Visco Analyser (RVA). Maximum and minimum peak viscosity for rice extrudates alone and rice extrudates blended with 15% peas were 697 cp and 523 cp, respectively. There was a decreasing trend in degree of gelatinization with increase in legume incorporation level. Other RVA rheological parameters like trough break down and final viscosity were in the range of 266-226 cp, 431-297 cp and 452-375 cp respectively. Maximum values of protein, fat, fibre and ash contents were found in rice extrudates at 15% legumes blend levels. There was an increasing trend in nutrient contents with legume content in rice extrudates. Degree of gelatinization for rice alone extrudate was 29.4% and showed a decrease in gelatinization with increase in legumes extrudate and was minimum (22.4%) for rice blended with 15% dehulled green gram. Sensory evaluation scores for all extrudates showed the most acceptable range of 6 to 8. Thus, legume blend level (up to 15%) of dehulled legumes fetched good scores and showed promising trend for the production of low cost expanded extrudates and its instant flour. PMID:24082277

  12. Development of a Twin-Screw D-2 Extruder for the ITER Pellet Injection System

    International Nuclear Information System (INIS)

    A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. The extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with single-stage gas gun into the plasma. A one-fifth ITER scale prototype extruder has been built to produce a continuous solid deuterium extrusion. Deuterium gas is precooled and liquefied before being introduced into the extruder. The precooler consists of a copper vessel containing liquid nitrogen surrounded by a deuterium gas filled copper coil. The liquefier is comprised of a copper cylinder connected to a Cryomech AL330 cryocooler, which is surrounded by a copper coil that the precooled deuterium flows through. The lower extruder barrel is connected to a Cryomech GB-37 cryocooler to solidify the deuterium (at approximate to 15 K) before it is forced through the extruder nozzle. A viewport located below the extruder nozzle provides a direct view of the extrusion. A camera is used to document the extrusion quality and duration. A data acquisition system records the extruder temperatures, torque, and speed, upstream, and downstream pressures. This paper will describe the prototype twin-screw extruder and initial extrusion results.

  13. Catalyst Architecture

    DEFF Research Database (Denmark)

    Kiib, Hans; Marling, Gitte; Hansen, Peter Mandal

    2014-01-01

    How can architecture promote the enriching experiences of the tolerant, the democratic, and the learning city - a city worth living in, worth supporting and worth investing in? Catalyst Architecture comprises architectural projects, which, by virtue of their location, context and their combination...... of programs, have a role in mediating positive social and/or cultural development. In this sense, we talk about architecture as a catalyst for: sustainable adaptation of the city’s infrastructure appropriate renovation of dilapidated urban districts strengthening of social cohesiveness in the city...

  14. Thermal stability of hydrostatically extruded EUROFER 97 steel

    International Nuclear Information System (INIS)

    EUROFER 97 steel is a candidate structural material for the future fusion power reactors, as well as for the European Test Blanket Modules (TBMs) to be tested in ITER. In the reported study, the microstructure of EUROFER 97 was modified by hydrostatic extrusion (HE) which reduced the grain size from 400 to 86 nm and that of the carbide particles from 111 to 75 nm. The changes in the microstructure significantly improved the strength of the extruded samples. However, it is important that the enhanced properties of nanostructured materials are stable over the required range of intended service temperature. The thermal stability of the nanostructured EUROFER steel was evaluated by subjecting the hydrostatically extruded samples to annealing at temperatures ranging from 473 to 1073 K (200-800 deg. C) for 1 h. Tensile tests and microhardness measurements with a 200 g load were carried out on the annealed samples to determine the effect of the heat treatment. The results show that the highest microhardness (403 HV0.2) was achieved for samples annealed at 673 K. However, the tensile and yield strength decreased at the higher temperature of 873 K and the total elongation increased to 15%, compared to only 3% for as-extruded samples. The changes in the mechanical properties were rationalized by the examination of the microstructural changes. During heating the initial grain size remains virtually unchanged below a temperature of 873 K. However, above 873 K the grain size increased and it is very likely that growth will be very rapid at higher temperatures.

  15. Dislocations in extruded Co-49.3 at. pct Al

    Science.gov (United States)

    Yaney, D. L.; Nix, W. D.; Pelton, A. R.

    1986-01-01

    Polycrystalline Co-49.3 at. pct Al, which had been extruded at 1505 K, was examined using transmission electron microscopy. Diffraction contrast analysis showed that b = 100 as well as b = 111 line dislocations contribute to elevated temperature deformation in CoAl. Therefore, it was concluded that sufficient slip systems exist in CoAl to allow for general plasticity in the absence of diffusional mechanisms. Line dislocations of the type b = 001 were observed on both 110 and 100 planes while b = 111 line dislocations were observed on 1 -1 0 planes.

  16. Effects of extruded soybeans on CLA concentration in milk

    Directory of Open Access Journals (Sweden)

    A. Formigoni

    2011-03-01

    Full Text Available Conjugated linoleic acids are geometric and positional isomers of the linoleic acid (Bessa et al., 2000. Recent studies on animal models demonstrated that these intermediates of rumen biohydrogenation may improve health by anticarcinogenic, antiatherogenic, antiobesity and antidiabetic effects and immune system enhancement (Bauman et al., 2001; Pariza et al., 2000; Belury 2002; Peterson et al., 2002. So aim of this work was to study the possibility to increase CLA milk content by the use of a natural source of polyunsaturated fatty acids as extruded soybeans........

  17. Radiation effects on extruded and compression molded UHMWPE

    International Nuclear Information System (INIS)

    Radiation sterilization of Ultra-high Molecular Weight Polyethylene (UHMWPE) has been shown to produce crystallinity changes in the resin. Previous studies have assumed material property changes to be isotropic. Two grades of UHMWPE (GUR 415 ampersand GUR 412) produced by two different processes (ram extrusion and compression molding) were evaluated for radiation sterilization induced property changes. At low radiation doses (2.8 Mrads) extruded GUR 415 property responses were isotropic. At higher doses (5.0 Mrad) an anisotropic response was observed. Property changes in compression molded GUR 412 were found to be anisotropic at both sterilization dose levels investigated

  18. Energy consumption analysis for a single screw extruder

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jing; Harkin-Jones, Eileen; Price, Mark; Karnachi, Nayeem [Queen' s Univ., Belfast (United Kingdom). School of Mechanical and Aerospace Engineering; Li, Kang [Queen' s Univ., Belfast (United Kingdom). School of Electronics, Electrical Engineering and Computer Science; Fei, Minrui [Shanghai Univ. (China). School of Mechatronic Engineering and Automation

    2013-07-01

    Polymer extrusion is regarded as an energy intensive production process, the real-time monitoring of both thermal energy and motor drive energy consumption becomes necessary for the development of energy efficient management system. The use of power meter is a simple and easy way to achieve this, however the cost sometimes can be high. Mathematical models based on the process settings provide an affordable alternative, but the resultant models cannot be easily extended to other extruders with different geometry. In this paper, simple and accurate energy real-time monitoring methods are developed for the analysis of energy consumption of the thermal heating and motor drive respectively. This is achieved by looking inside the controller, and use the control variables to calculate the power consumption. The developed methods are then adopted to study the effects of operating settings on the energy efficiency. These include the barrel heating temperature, water cooling temperature, and screw speed. The experimental results on Killion KTS-100 extruder show that the barrel heating temperature has a negative effect on energy efficiency, while the water cooling setting affects the energy efficiency positively but insignificantly. Undoubtedly, screw speed has the most significant effect on energy efficiency.

  19. Production and characterization of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices

    Energy Technology Data Exchange (ETDEWEB)

    Zepon, Karine Modolon [CIMJECT, Departamento de Engenharia Mecânica, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); TECFARMA, Universidade do Sul de Santa Catarina, 88704-900 Tubarão, SC (Brazil); Petronilho, Fabricia [FICEXP, Universidade do Sul de Santa Catarina, 88704-900 Tubarão, SC (Brazil); Soldi, Valdir [POLIMAT, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Salmoria, Gean Vitor [CIMJECT, Departamento de Engenharia Mecânica, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Kanis, Luiz Alberto, E-mail: luiz.kanis@unisul.br [TECFARMA, Universidade do Sul de Santa Catarina, 88704-900 Tubarão, SC (Brazil)

    2014-11-01

    The production and evaluation of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices are reported herein. The matrices were melt extruded under nine different conditions, altering the temperature and the screw speed values. The surface morphology of the matrices was examined by scanning electron microscopy. The micrographs revealed the presence of non-melted silver sulfadiazine microparticles in the matrices extruded at lower temperature and screw speed values. The thermal properties were evaluated and the results for both the biopolymer and the drug indicated no thermal degradation during the melt extrusion process. The differential scanning analysis of the extrudate matrices showed a shift to lower temperatures for the silver sulfadiazine melting point compared with the non-extruded drug. The starch/cellulose acetate matrices containing silver sulfadiazine demonstrated significant inhibition of the growth of Pseudomonas aeruginosa and Staphylococcus aureus. In vivo inflammatory response tests showed that the extrudate matrices, with or without silver sulfadiazine, did not trigger chronic inflammatory processes. - Highlights: • Melt extruded bio-based matrices containing silver sulfadiazine was produced. • The silver sulfadiazine is stable during melt-extrusion. • The extrudate matrices shown bacterial growth inhibition. • The matrices obtained have potential to development wound healing membranes.

  20. Effects of extrusion conditions on the physicochemical properties of extruded red ginseng.

    Science.gov (United States)

    Gui, Ying; Gil, Sun Kuk; Ryu, Gi Hyung

    2012-09-01

    The effects of variable moisture content, screw speed and barrel temperature on the physicochemical properties of red ginseng powder extrudates were investigated. The raw red ginseng powders were processed in a co-rotating intermeshing twin-screw extruder. Primary extrusion variables were feed moisture content (20 and 30%), screw speed (200 and 250 rpm) and barrel temperature (115 and 130°C). Extruded red ginseng showed higher crude saponin contents (6.72~7.18%) than raw red ginseng (5.50%). Tested extrusion conditions did not significantly affect the crude saponin content of extrudates. Increased feed moisture content resulted in increased bulk density, specific length, water absorption index (WAI), breaking strength, elastic modulus and crude protein content and decreased water solubility index (WSI) and expansion (p<0.05). Increased barrel temperature resulted in increased total sugar content, but decreased reducing sugar content in the extrudate (p<0.05). Furthermore, increased barrel temperature resulted in increased amino acid content and specific length and decreased expansion and bulk density of extrudates only at a higher feed moisture content. The physicochemical properties of extrudates were mainly dependent on the feed moisture content and barrel temperature, whereas the screw speed showed a lesser effect. These results will be used to help define optimized process conditions for controlling and predicting qualities and characteristics of extruded red ginseng. PMID:24471085

  1. Modelling extrudate expansion in a twin-screw food extrusion cooking process through dimensional analysis methodology

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2010-01-01

    A new phenomenological model is proposed to correlate extrudate expansion and extruder operation parameters in a twin-screw food extrusion cooking process. Buckingham's pi dimensional analysis method is applied to establish the model. Three dimensionless groups, i.e. pump efficiency, water content...

  2. THE GRAFTING OF MALEIC-ANHYDRIDE ON HIGH-DENSITY POLYETHYLENE IN AN EXTRUDER

    NARCIS (Netherlands)

    GANZEVELD, KJ; JANSSEN, LPBM

    1992-01-01

    The grafting of maleic anhydride (MAH) on high density polyethylene in a counter-rotating twin screw extruder has been studied. As the reaction kinetics appear to be affected by mass transfer, good micro mixing in the extruder is important. Due to the competing mechanisms of increasing mixing and de

  3. [Physico-chemical evaluation of products extruded with sorghum-corn-soybean blends].

    Science.gov (United States)

    Gutiérrez, R R; Gómez, M H

    1988-03-01

    Yellow corn grits (M), brown sorghum (SM), white sorghum (SB) and full fat soy flour (S) blends were extruded in an autogenous Brady Crop Cooker extruder at 195-200 degrees C and 11% moisture content. Binary blends (70:30) made up of M:S, SM:S and SB:S; and ternary blends (30:40:30) made up of SM:M:S and SB:M:S were extruded. Under these conditions, extrudates contained about 19% protein and 6% fat, which are within the specifications given for cereal/oil seed blends. Raw and extruded samples were analyzed for ES, WQI, WSI, MD and paste viscosity. All blends underwent modifications in the starch fraction at granular and molecular level. Brown sorghum extrudates presented higher degradation than those of white sorghum and corn:soy blends, although the last ones gave similar responses to analitical techniques. Extrudates greatly increased their ES, SWI and MD values, suggesting that degradation products, like dextrins, were present. Cooked paste low viscosities (50 degrees C) and micrographs support these findings. Because of their functional characteristics, extrudates could be used in beverages. PMID:3256283

  4. Production and characterization of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices

    International Nuclear Information System (INIS)

    The production and evaluation of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices are reported herein. The matrices were melt extruded under nine different conditions, altering the temperature and the screw speed values. The surface morphology of the matrices was examined by scanning electron microscopy. The micrographs revealed the presence of non-melted silver sulfadiazine microparticles in the matrices extruded at lower temperature and screw speed values. The thermal properties were evaluated and the results for both the biopolymer and the drug indicated no thermal degradation during the melt extrusion process. The differential scanning analysis of the extrudate matrices showed a shift to lower temperatures for the silver sulfadiazine melting point compared with the non-extruded drug. The starch/cellulose acetate matrices containing silver sulfadiazine demonstrated significant inhibition of the growth of Pseudomonas aeruginosa and Staphylococcus aureus. In vivo inflammatory response tests showed that the extrudate matrices, with or without silver sulfadiazine, did not trigger chronic inflammatory processes. - Highlights: • Melt extruded bio-based matrices containing silver sulfadiazine was produced. • The silver sulfadiazine is stable during melt-extrusion. • The extrudate matrices shown bacterial growth inhibition. • The matrices obtained have potential to development wound healing membranes

  5. Effect of Apple and Rosehip Pomaces on Colour, Total Phenolics and Antioxidant Activity of Corn Extruded Snacks

    OpenAIRE

    Drożdż Wioletta; Tomaszewska-Ciosk Ewa; Zdybel Ewa; Boruczkowska Hanna; Boruczkowski Tomasz; Regiec Piotr

    2014-01-01

    Extrusion cooking technology was applied for obtaining corn extrudates fortified with various level (10-20%) of rosehip pomace powder or apple pomace powder. The total polyphenols content, antioxidant activities (ABTS), organoleptic properties and colour of the extrudates were determined.

  6. Effect of blend moisture and extrusion temperature on physical properties of everlasting pea-wheat extrudates.

    Science.gov (United States)

    Zarzycki, P; Kasprzak, M; Rzedzicki, Z; Sobota, A; Wirkijowska, A; Sykut-Domańska, E

    2015-10-01

    The effect of everlasting pea in combination with wheat on physical properties and microstructure of extrudates were studied. The share of everlasting pea (Lathyrus sativus) was variable, at 35, 50 and 65 %, respectively. The everlasting pea-wheat mixtures were moistened to the required level (18, 21, and 24 %), homogenized, conditioned and extruded in twin-screw extruder with counter-rotating conical screws. All of the obtained extrudates were characterised by a slow degree of radial expansion and high specific density. The Pearson correlation analysis indicated a statistically significant linear Pearson correlation (p extrusion-cooker in the study permitted the production of compact, hard everlasting pea-wheat extrudates for use in vegetarian lunch dishes. PMID:26396414

  7. Effect of Extrusion Variables on the Hardness of Lentil Semolina Extrudates

    Science.gov (United States)

    Petrova, Todorka; Ruskova, Milena; Tzonev, Panayot; Zsivanovits, Gabor; Penov, Nikolay

    2010-01-01

    Lentil semolina was extruded in a laboratory single screw extruder (Brabender 20 DN, Germany) with screw diameter 19 mm and die diameter 5 mm. Effects of moisture content, barrel temperature, metering zone temperature, screw speed, and screw compression ratio on hardness of the extruded products were studied. Response surface methodology with combinations of moisture content (18, 22, 25, 28, 32%), metering zone temperature (136, 150, 160, 170, 184° C), barrel temperature (136, 150, 160, 170, 184° C), screw speed (132, 160, 180, 200, 228 rpm), and screw compression ratio (1:1, 2:1, 3:1, 4:1, 5:1) was applied. Feed screw speed was fixed at 70 rpm. Feed zone temperature was kept constant at 150° C. The hardness of the extrudates was measured with a TA.XT Plus Texture Analyser, Stable Micro Systems. The textural profiles of the extrudates showed that feed moisture had the highest effect on the hardness.

  8. Design and Analysis of Single Screw Extruder for Jatropha Seeds Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Ali Nurrakhmad Siregar

    2014-03-01

    Full Text Available Mechanical extraction is commonly used to extract oils from vegetable seeds and a single screw extruder has been successfully reported to separate oil and cake from Jatropha curcas seeds. In this study, a single screw extruder was designed and analyzed using Finite Element Method (FEM and Computational Fluid Dynamics (CFD. Three different geometrical dimensions of screw extruder were designed and analyzed using FEM and CFD with software ANSYS POLYFLOW to study simulation of the flow and the behavior of Jatropha dough through of a single screw extruder. In a preliminary study, this study focused to simulate the velocity profile and local shear rate indie section with a power law model. The result obtained revealed that three important are as in designing a single screw extruder were gap area (clearance in the range of 0.5-1.0 mm, chamber area (normal pitch in the range 17-22 mm and root area.

  9. Ductility enhancement of extruded magnesium via yttrium addition

    International Nuclear Information System (INIS)

    Two binary Mg-Y alloys and pure magnesium were prepared by extrusion. The effect of yttrium on mechanical properties was investigated in comparison between the pure magnesium and the Mg-Y alloys. The results showed that after extruded and annealed, with increment of the yttrium addition, the elongation-to-failure of magnesium increases, but the strength decreases. This is mainly due to the different textures that make the difference of deformation modes in tensile along ED direction for the pure magnesium and the Mg-Y alloys. The pure magnesium has the texture with {0 0 0 2} pole perpendicular to ED. However more random components of texture are formed in the Mg-Y alloys. Accordingly, the Mg-Y alloys can be deformed with more active dislocation slips than the pure magnesium.

  10. Study of Energetic Nitramine Extruded Double-Base Propellants

    Directory of Open Access Journals (Sweden)

    G. K. Gautam

    1998-04-01

    Full Text Available This paper gives the results of an experimental study on nitramine extruded double-base (EDBfonnulationscontaining up to 25 percent RDXin low and high calorimetric value double-base(DBpropellants. The effect of ballistic modifiers on the burn rate and pressure exponent ( 11 of promisingfonnulations has also been investigated. The data generated on various parameters reveal that ( initraniine EDB propellants exhibit relatively superior thennal stability,' (ii tensile strength andpercentage elongation are drastically altered if RDX concentration exceeds 15 per cent, (iii 11 islowered significantly in the presence of ballistic modifiers, (iv characteristic velocity (C* values arehigher to that for the control tonnulation, and ( v temperature sensitivity of burn rate is on the lowerside (0,20 -0.25 % / °C as against 0.40 % / °C in the presence of ballistic modifiers.

  11. Properties of extruded xanthan-starch-clay nanocomposite films

    Directory of Open Access Journals (Sweden)

    Cristina de Melo

    2011-12-01

    Full Text Available The aim of this work was to manufacture the biodegradable nanocomposite films by extrusion from different combinations of cassava starch, xanthan gum and nanoclays (sodium montmorillonite - MMT- Na and to characterize them according to their microstructure, optical, mechanical and barrier properties. Films were manufactured from nine starch/xanthan/nanoclay combinations, containing glycerol as plasticizer. Scanning electron microscopy (SEM of the starch-xanthan extruded films showed reticulated surface and smooth interior, indicating that the gum was mostly concentrated on the surface of the films, while starch/xanthan/nanoclays films showed a more homogeneous surface, suggesting that the introduction of nanoclays provided a better biopolymeric interaction. In general, nanoclays addition (2.5 - 5.0, w% generated more transparent and resistant films, with lower water vapor permeabilities and lower water sorption capacities and xanthan gum addition improved the elongation ofa starch films.

  12. THE OPTIMIZATION OF FLOW RATES OF AN EXTRUDER

    Directory of Open Access Journals (Sweden)

    I.O. Popoola

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The article addresses how the flow rates of an extruder can be optimized. It mentions the plastic recycling industry as an example, which is only one of many solid waste recycling industries. The literature on flow rates is reviewed to demonstrate a gap that the current study aims to fills, in the hope that it will stimulate further research in a fertile area.

    AFRIKAANSE OPSOMMING: Die artikel adresseer die vraagstuk van vloeitempo van ‘n ekstrusieproses. Dit handel met ‘n voorbeeld van ‘n plastiekherwinningsproses wat spruit uit soliede afvalverwerking. ‘n Literatuurstudie toon hoedat die navorsing verdere areas wat braak lê, aanspreek in die hoop dat verdere studie gestimuleer sal word.

  13. MICROSTRUCTURE AND MECHANICAL PROPERTIES OF AZ91D EXTRUDED TUBE

    Institute of Scientific and Technical Information of China (English)

    B.Y. Yu; C.L. Bao; H.W. Song; Z. Liu; H.P. Yu

    2006-01-01

    The effect of extrusion ratio on microstructures and mechanical properties of magnesium alloy AZ91D extruded tube at 430℃ has been studied. After the evolution of microstructure and mechanical properties of AZ91D during extrusion were studied, the following parameters were obtained: tensile strength reached the climax value of 306.9MPa and elongation peak value of10.1% at an extrusion ratio of 7.125, and with the increase of the extrusion ratio to 7.45, yield strength reached a top value of 285.795MPa with decreased tensile strength and elongation. It was concluded that mechanical properties of magnesium alloys AZ91D could be enhanced by adjusting the extrusion ratio near recrystallization.

  14. Aligning carbon fibers in micro-extruded composite ink

    Science.gov (United States)

    Mahajan, Chaitanya G.

    Direct write processes include a wide range of additive manufacturing techniques with the ability to fabricate structures directly onto planar and non-planar surfaces. Most additive manufacturing techniques use unreinforced polymers to produce parts. By adding carbon fiber as a reinforcing material, properties such as mechanical strength, electrical conductivity, and thermal conductivity can be enhanced. Carbon fibers can be long and continuous, or short and discontinuous. The strength of carbon fiber composite parts is greatly increased when the fibers are preferentially aligned. This research focuses on increasing the strength of additively manufactured parts reinforced using discontinuous carbon fibers that have been aligned during the micro extrusion process. A design of experiments (DOE) approach was used to identify significant process parameters affecting fiber alignment. Factors such as the length of carbon fibers, nozzle diameter, fiber loading fraction, air pressure, translational speed and standoff distance were considered. A two dimensional Fast Fourier Transform (2D FFT) was used to quantify the degree of fiber alignment in the extruded composite inks. ImageJ software supported by an oval profile plugin was used with micrographs of printed samples to obtain the carbon fiber alignment values. The optimal value for the factors was derived by identifying the significant main and interaction effects. Based on the results of the DOE, tensile test samples were printed with fibers aligned parallel and perpendicular to the tensile axis. A standard test method for tensile properties of plastic revealed that the extruded parts with fibers aligned along the tensile axis were better in tensile strength and modulus.

  15. Autocalibrating Tiled Projectors on Piecewise Smooth Vertically Extruded Surfaces.

    Science.gov (United States)

    Sajadi, Behzad; Majumder, Aditi

    2011-09-01

    In this paper, we present a novel technique to calibrate multiple casually aligned projectors on fiducial-free piecewise smooth vertically extruded surfaces using a single camera. Such surfaces include cylindrical displays and CAVEs, common in immersive virtual reality systems. We impose two priors to the display surface. We assume the surface is a piecewise smooth vertically extruded surface for which the aspect ratio of the rectangle formed by the four corners of the surface is known and the boundary is visible and segmentable. Using these priors, we can estimate the display's 3D geometry and camera extrinsic parameters using a nonlinear optimization technique from a single image without any explicit display to camera correspondences. Using the estimated camera and display properties, the intrinsic and extrinsic parameters of each projector are recovered using a single projected pattern seen by the camera. This in turn is used to register the images on the display from any arbitrary viewpoint making it appropriate for virtual reality systems. The fast convergence and robustness of this method is achieved via a novel dimension reduction technique for camera parameter estimation and a novel deterministic technique for projector property estimation. This simplicity, efficiency, and robustness of our method enable several coveted features for nonplanar projection-based displays. First, it allows fast recalibration in the face of projector, display or camera movements and even change in display shape. Second, this opens up, for the first time, the possibility of allowing multiple projectors to overlap on the corners of the CAVE-a popular immersive VR display system. Finally, this opens up the possibility of easily deploying multiprojector displays on aesthetic novel shapes for edutainment and digital signage applications. PMID:21301026

  16. Preparation and characterization of as-extruded Mg–Sn alloys for orthopedic applications

    International Nuclear Information System (INIS)

    Highlights: • As-extruded Mg–Sn alloys with various Sn content were fabricated. • Microstructure of alloys varied with increasing Sn content. • Mechanical properties of alloys could be adjusted by controlling the Sn content. • Corrosion properties of alloys could be adjusted by controlling the Sn content. • As-extruded Mg–1Sn and Mg–3Sn alloys did not induce toxicity to cells. - Abstract: In this study, as-extruded Mg–Sn alloys with various Sn content were prepared and characterized for orthopedic applications. The results of microstructure observations and X-ray diffraction analysis showed that as-extruded Mg–Sn alloys were composed of α-Mg and Mg2Sn phases, and the content of Mg2Sn phase increased with increasing Sn content. The microstructure of as-extruded Mg–Sn alloy with 1 wt.% Sn was equiaxed grain, while the one with a higher Sn content was inhomogeneous microstructure and the grain size of the long elongated grains decreased with increasing Sn content. Tensile test revealed that the yield strength and ultimate tensile strength of as-extruded Mg–Sn alloys increased while the elongation decreased with increasing Sn content. Immersion and electrochemical tests indicated that the microstructure of as-extruded Mg–Sn alloys affected their corrosion properties, and the increase of Mg2Sn phase resulted from the increase of the Sn content led to a higher corrosion rate. The cytotoxicity test showed that as-extruded Mg–1Sn and Mg–3Sn alloys met the requirement of cell toxicity for orthopedic applications. Our analyses showed that as-extruded Mg–1Sn and Mg–3Sn alloys were promising to be used as biodegradable orthopedic implants

  17. Development of repetitive railgun pellet accelerator and steady-state solid hydrogen extruder

    International Nuclear Information System (INIS)

    Development of a railgun pellet accelerator and a steady-state solid hydrogen extruder has been conducted. A railgun accelerator has been investigated for a high-speed repetitive pellet acceleration. The final objective is to develop a railgun system that can achieve a 5km/s speed-class repetitive (2Hz) pellet injection. Improvement in the acceleration efficiency showed a pellet velocity of more than 2km/s using augment rails and a ceramic insulator applied to a 1m-long railgun. The other investigation focused on the development of a steady-state solid hydrogen extruder for continuous pellet injection. Screw-driven extruding system has been chosen to extrude the solid hydrogen filament continuously. Theoretical considerations suggest that temperature control of the system is important in future research. (orig.)

  18. Investigations of the mixing behaviour of pin-type rubber extruders

    Science.gov (United States)

    Schöppner, Volker; Schadomsky, Michael; Hopmann, Christian; Lemke, Florian

    2016-03-01

    This paper deals with investigations of the mixing behaviour of rubber extruders. The requirement to obtain a high-quality elastomer product is a thermally and materially homogenous rubber mixture. Because of the highly viscous and multicomponent nature of rubber mixture, extruders require a thoroughly distributive and dispersive mixing behaviour. The current state of the art is the pin-type rubber extruder with cylindrical pins which extend radially into the screw channel, causing a constant deformation and reorientation of the rubber melt. As mixing is of crucial importance, the mixing behaviour of pin-type rubber extruders is analysed with the goal of optimising it. The starting point of the optimisation is the current cylindrical pins. Over the course of the investigation, new pin designs and geometrical arrangements are investigated.

  19. Extraction of light filth from rice flours, extruded rice products, and rice paper: collaborative study.

    Science.gov (United States)

    Dent, R G

    1982-09-01

    Two new methods were developed for the extraction of rodent hairs and insect fragments from rice products: one for rice flour and one for extruded rice products and rice paper. A 100 g sample of rice flour was extracted with mineral oil-40% isopropanol, followed by a water phase as needed for additional cycles. For extruded rice products and rice paper, a 225 g sample of each was initially extracted as above, followed by a single extraction with mineral oil-20% isopropanol. Both methods used an acid hydrolysis pretreatment followed by wet sieving and a percolator extraction. Average rodent hair recoveries were 77.8% for rice flour and 82.2% for extruded rice products and rice paper. Average insect fragment recoveries were 89.6% for rice flour and 91.9% for extruded rice products and rice paper. Both methods were adopted official first action. PMID:7130079

  20. Extrusion of Fe2O3/SBA-15 mesoporous material for application as heterogeneous Fenton-like catalyst

    Directory of Open Access Journals (Sweden)

    María Isabel Pariente

    2015-03-01

    Full Text Available The aim of this work has been the extrusion of powder Fe2O3/SBA-15 catalyst in order to be successfully used in continuous catalytic fixed bed reactors as Fenton-like catalyst. The extrusion method was optimised using an amorphous silica material of similar properties than the Fe2O3/SBA-15 catalyst. The main studied variable was the composition of the extrusion paste using bentonite and methylcellulose as inorganic and organic binders, respectively. The organic content displayed a significant influence on the mechanical strength and specific surface area of the final extrudates. In contrast, the inorganic binder content hardly affected the final properties (in the studied range. The extruded Fe2O3/SBA-15 material showed a remarkable mechanical strength as well as the typical mesoporous structure of Fe2O3/SBA-15 with a relevant specific surface area (264 m2/g. The extruded catalyst achieved a high catalytic performance in the catalytic wet peroxide oxidation of phenol with a 60 % of total organic carbon reduction in both batch and continuous processes.

  1. ACID-EXTRUDING TRANSPORTERS IN MAMMARY AND PANCREATIC ADENOCARCINOMA: REGULATION AND ROLES IN CELL MOTILITY

    OpenAIRE

    Pedersen, S.

    2013-01-01

    A fundamental property of solid tumors is an altered pH-profile compared to normal tissues. This at least in part reflects increased glycolytic metabolism, necessitating increased acid extrusion to maintain survival, and in turn stimulating cancer cell motility [1, 2]. Acid extruding transporters are therefore interesting potential targets in cancer. The overall aim of these studies was to explore the regulation and roles of acid extruding transporters in human mammary and pancreatic adenocar...

  2. Insensitive explosive composition and method of fracturing rock using an extrudable form of the composition

    Science.gov (United States)

    Davis, Lloyd L

    2013-11-05

    Insensitive explosive compositions were prepared by reacting di-isocyanate and/or poly-isocyanate monomers with an explosive diamine monomer. Prior to a final cure, the compositions are extrudable. The di-isocyanate monomers tend to produce tough, rubbery materials while polyfunctional monomers (i.e. having more than two isocyanate groups) tend to form rigid products. The extrudable form of the composition may be used in a variety of applications including rock fracturing.

  3. Extraction of oil from jatropha seeds using a twin-screw extruder: Feasibility study

    OpenAIRE

    Evon, Philippe; Kartika, Ika Amalia; Cerny, Muriel; Rigal, Luc

    2013-01-01

    International audience The objective of this study was to evaluate the feasibility of mechanical pressing to extract oil from jatropha seeds using a twin-screw extruder. Experiments were conducted using a co-rotating (Clextral BC 21, France) twin-screw extruder. The influence of operating conditions on oil yield, specific mechanical energy and oil quality was examined. Operating conditions included screw configuration, pressing temperature and screw rotation speed. Generally, it was the sc...

  4. Conformal optimal design and processing of extruding die cavity

    Institute of Scientific and Technical Information of China (English)

    齐红元; 陈科山; 杜凤山

    2008-01-01

    Aimed at the optimal analysis and processing technology of die cavity of special-shaped products extrusion, by numerical analysis of trigonometric interpolation and Conformal Mapping theory, on the non-circle cross-section of special-shaped products, the conformal mapping function can be set up to translate the cross-section region into unit dish region, over numerical finite interpolation points between even and odd. Products extrusion forming can be turned into two-dimension problem, and plastic stream function can be deduced, as well as the mathematical model of the die cavity surface is established based on deferent kinds of vertical curve. By applying Upper-bound Principle, the vertical curves and related parameters of die cavity are optimized. Combining with electrical discharge machining (EDM) process and numerical control (NC) milling machine technology, the optimal processing of die cavity can be realized. Taking ellipse-shaped products as an instance, the optimal analysis and processing of die cavity including extruding experiment are carried out.

  5. Hot extruded carbon nanotube reinforced aluminum matrix composite materials

    Science.gov (United States)

    Kwon, Hansang; Leparoux, Marc

    2012-10-01

    Carbon nanotube (CNT) reinforced aluminum (Al) matrix composite materials were successfully fabricated by mechanical ball milling followed by powder hot extrusion processes. Microstructural analysis revealed that the CNTs were well dispersed at the boundaries and were aligned with the extrusion direction in the composites obtained. Although only a small quantity of CNTs were added to the composite (1 vol%), the Vickers hardness and the tensile strength were significantly enhanced, with an up to three-fold increase relative to that of pure Al. From the fractography of the extruded Al-CNT composite, several shapes were observed in the fracture surface, and this unique morphology is discussed based on the strengthening mechanism. The damage in the CNTs was investigated with Raman spectroscopy. However, the Al-CNT composite materials were not only strengthened by the addition of CNTs but also enhanced by several synergistic effects. The nanoindentation stress-strain curve was successfully constructed by setting the effective zero-load and zero-displacement points and was compared with the tensile stress-strain curve. The yield strengths of the Al-CNT composites from the nanoindentation and tensile tests were compared and discussed. We believe that the yield strength can be predicted using a simple nanoindentation stress/strain curve and that this method will be useful for materials that are difficult to machine, such as complex ceramics.

  6. Hot extruded carbon nanotube reinforced aluminum matrix composite materials

    International Nuclear Information System (INIS)

    Carbon nanotube (CNT) reinforced aluminum (Al) matrix composite materials were successfully fabricated by mechanical ball milling followed by powder hot extrusion processes. Microstructural analysis revealed that the CNTs were well dispersed at the boundaries and were aligned with the extrusion direction in the composites obtained. Although only a small quantity of CNTs were added to the composite (1 vol%), the Vickers hardness and the tensile strength were significantly enhanced, with an up to three-fold increase relative to that of pure Al. From the fractography of the extruded Al–CNT composite, several shapes were observed in the fracture surface, and this unique morphology is discussed based on the strengthening mechanism. The damage in the CNTs was investigated with Raman spectroscopy. However, the Al–CNT composite materials were not only strengthened by the addition of CNTs but also enhanced by several synergistic effects. The nanoindentation stress–strain curve was successfully constructed by setting the effective zero-load and zero-displacement points and was compared with the tensile stress–strain curve. The yield strengths of the Al–CNT composites from the nanoindentation and tensile tests were compared and discussed. We believe that the yield strength can be predicted using a simple nanoindentation stress/strain curve and that this method will be useful for materials that are difficult to machine, such as complex ceramics. (paper)

  7. Differences in time-dependent mechanical properties between extruded and molded hydrogels.

    Science.gov (United States)

    Ersumo, N; Witherel, C E; Spiller, K L

    2016-01-01

    The mechanical properties of hydrogels used in biomaterials and tissue engineering applications are critical determinants of their functionality. Despite the recent rise of additive manufacturing, and specifically extrusion-based bioprinting, as a prominent biofabrication method, comprehensive studies investigating the mechanical behavior of extruded constructs remain lacking. To address this gap in knowledge, we compared the mechanical properties and swelling properties of crosslinked gelatin-based hydrogels prepared by conventional molding techniques or by 3D bioprinting using a BioBots Beta pneumatic extruder. A preliminary characterization of the impact of bioprinting parameters on construct properties revealed that both Young's modulus and optimal extruding pressure increased with polymer content, and that printing resolution increased with both printing speed and nozzle gauge. High viability (>95%) of encapsulated NIH 3T3 fibroblasts confirmed the cytocompatibility of the construct preparation process. Interestingly, the Young's moduli of extruded and molded constructs were not different, but extruded constructs did show increases in both the rate and extent of time-dependent mechanical behavior observed in creep. Despite similar polymer densities, extruded hydrogels showed greater swelling over time compared to molded hydrogels, suggesting that differences in creep behavior derived from differences in microstructure and fluid flow. Because of the crucial roles of time-dependent mechanical properties, fluid flow, and swelling properties on tissue and cell behavior, these findings highlight the need for greater consideration of the effects of the extrusion process on hydrogel properties. PMID:27550945

  8. Hot Deformation Mechanisms in AZ31 Magnesium Alloy Extruded at Different Temperatures: Impact of Texture

    Directory of Open Access Journals (Sweden)

    Karl Ulrich Kainer

    2012-08-01

    Full Text Available The hot deformation characteristics of AZ31 magnesium alloy rod extruded at temperatures of 300 °C, 350 °C and 450 °C have been studied in compression. The extruded material had a fiber texture with  parallel to the extrusion axis. When extruded at 450 °C, the texture was less intense and the  direction moved away from the extrusion axis. The processing maps for the material extruded at 300 °C and 350 °C are qualitatively similar to the material with near-random texture (cast-homogenized and exhibited three dynamic recrystallization (DRX domains. In domains #1 and #2, prismatic slip is the dominant process and DRX is controlled by lattice self-diffusion and grain boundary self-diffusion, respectively. In domain #3, pyramidal slip occurs extensively and DRX is controlled by cross-slip on pyramidal slip systems. The material extruded at 450 °C exhibited two domains similar to #1 and #2 above, which moved to higher temperatures, but domain #3 is absent. The results are interpreted in terms of the changes in  fiber texture with extrusion temperature. Highly intense  texture, as in the rod extruded at 350 °C, will enhance the occurrence of prismatic slip in domains #1 and #2 and promotes pyramidal slip at temperatures >450 °C (domain #3.

  9. 稳态实验考察经模拟道路老化的全配方稀燃Nox捕集催化剂上的Nox还原%NOx Reduction on Fully Formulated Lean NOx Trap Catalysts Subjected to Simulated Road Aging: Insights from Steady-State Experiments

    Institute of Scientific and Technical Information of China (English)

    Jin WANG; Yaying JI; Uschi GRAHAM; Caio CESAR SPINDOLA DE OLIVEIRA; Mark CROCKER

    2011-01-01

    Fully formulated lean NOx trap (LNT) catalysts of the type Pt/Rh/BaO/Al203 were prepared with and without incorporation of CeO2-ZrO2 in the washcoat, and their NOx reduction behavior was evaluated in steady-state, continuous flow experiments. In the fresh state, the CeO2-ZrO2 addition was found to exert little effect on NOx reduction activity using H2, CO, and NH3 as the reductants. However, after simulated road aging, NOx reduction activity was significantly impaired for the CeO2-ZrO2-free catalyst, whereas the performance of the CeO2-ZrO2-containing analog was affected to only a minor degree. These differences are explained on the basis of high-resolution transmission electron microscopy measurements showing that Pt supported on CeO2-ZrO2 remained highly dispersed after aging, whereas Pt supported on BaO/Al203 underwent significant sintering. In addition, the Pt/CeO2-ZrO2 component did not accumulate sulfur during aging, unlike Pt/BaO/Al203 for which significant sulfation of the Ba phase occurred. For both catalysts, selectivity to NH3 in NO and NO2 reduction by H2 increased after the catalyst aging, indicative of a change in the relative surface coverages of N and H ad-atoms on the precious metal sites.

  10. Chemical and molecular properties of irradiated starch extrudates

    International Nuclear Information System (INIS)

    Corn starch samples containing 0, 25, 50, and 70% amylose were gamma-irradiated at 0 (native), 5, 10, 20, and 30 kGy. All starch samples were extrusion cooked at 140 degrees C barrel temperature, 140 rpm screw speed, and 18% moisture content (db) using a C. W. Brabender single-screw extruder. Starches irradiated at a 20-kGy dosage were extrusion cooked with and without hydrogen peroxide, potassium persulfate, or ceric ammonium nitrate. The quantity of free radicals produced on the starch increased with increasing irradiation dosages (0-30 kGy). Stability of the free radicals was greater for high-amylose starches than for those with low amylose. Extrusion-cooked starches had traces of free radical activity. Acidity of the irradiated starches increased (pH decreased) with increasing irradiation dosages. Gel permeation chromatographic separation of variously treated starches gave three fractions. Fraction I, mostly amylopectin, eluted at the void volume, whereas fraction II, mostly amylose, eluted at the latter part of the gel. Fraction 0, degraded products of amylopectin and amylose, mostly eluted closer to the total volume of the gel. Fraction I quantities of irradiated starches decreased with increasing irradiation dosages, whereas fraction II and III quantities correspondingly increased. Native starches with 0% amylose exhibited more than a fourfold decrease in fraction I content, whereas 70% amylose native starches showed less than a twofold decrease due to increasing irradiation dosages from 0 to 30 kGy. Extrusion cooking accelerated the degradation of fraction I for 0% amylose starches more than for 70% amylose starches. Both 2.5 and 5% concentrations of chemical additives caused excessive degradation of fraction I of starches irradiated at 20 kGy, consequently increasing reducing powers. Ceric ammonium nitrate caused the highest decrease in the iodine binding capacity of the starches. Fraction I clearly suffered more degradation due to irradiation, extrusion

  11. Apically extruded debris with three contemporary Ni-Ti instrumentation systems: An ex vivo comparative study

    Directory of Open Access Journals (Sweden)

    Logani Ajay

    2008-01-01

    Full Text Available Aim: To comparatively evaluate the amount of apically extruded debris when ProTaper hand, ProTaper rotary and ProFile systems were used for the instrumentation of root canals. Materials and Methods: Thirty minimally curved, mature, human mandibular premolars with single canals were randomly divided into three groups of ten teeth each. Each group was instrumented using one of the three instrumentation systems: ProTaper hand, ProTaper rotary and ProFile. Five milliliters of sterile water were used as an irrigant. Debris extruded was collected in preweighed polyethylene vials and the extruded irrigant was evaporated. The weight of the dry extruded debris was established by comparing the pre- and postinstrumentation weight of polyethylene vials for each group. Statistical Analysis: The Kruskal-Wallis nonparametric test and Mann-Whitney U test were applied to determine if significant differences existed among the groups ( P < 0.05. Results: All instruments tested produced a measurable amount of debris. No statistically significant difference was observed between ProTaper hand and ProFile system ( P > 0.05. Although ProTaper rotary extruded a relatively higher amount of debris, no statistically significant difference was observed between this type and the ProTaper hand instruments ( P > 0.05. The ProTaper rotary extruded significantly more amount of debris compared to the ProFile system ( P < 0.05. Conclusion: Within the limitations of this study, it can be concluded that all instruments tested produced apical extrusion of debris. The ProTaper rotary extruded a significantly higher amount of debris than the ProFile.

  12. Foundation Flash Catalyst

    CERN Document Server

    Goralski, Greg

    2010-01-01

    This book offers an introduction to Flash Catalyst for designers with intermediate to advanced skills. It discusses where Catalyst sits within the production process and how it communicates with other programs. It covers all of the features of the Flash Catalyst workspace, teaching you how to create designs from scratch, how to build application designs and add functionality, and how to master the Catalyst/Flex workflow. * Introduces Flash Catalyst * Focuses on production process * Covers the interrelation between Flash Catalyst and Photoshop/Illustrator/Flex/Flash What you'll learn Starting f

  13. Characterization of three-way automotive catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Kenik, E.A.; More, K.L. [Oak Ridge National Laboratory, TN (United States); LaBarge, W. [General Motors-AC Delco Systems, Flint, MI (United States)] [and others

    1995-05-01

    This has been the second year of a CRADA between General Motors - AC Delco Systems (GM-ACDS) and Martin Marietta Energy Systems (MMES) aimed at improved performance/lifetime of platinum-rhodium based three-way-catalysts (TWC) for automotive emission control systems. While current formulations meet existing emission standards, higher than optimum Pt-Rh loadings are often required. In additionk, more stringent emission standards have been imposed for the near future, demanding improved performance and service life from these catalysts. Understanding the changes of TWC conversion efficiency with ageing is a critical need in improving these catalysts.

  14. Catalyst Deactivation: Control Relevance of Model Assumptions

    OpenAIRE

    Bernt Lie; David M. Himmelblau

    2000-01-01

    Two principles for describing catalyst deactivation are discussed, one based on the deactivation mechanism, the other based on the activity and catalyst age distribution. When the model is based upon activity decay, it is common to use a mean activity developed from the steady-state residence time distribution. We compare control-relevant properties of such an approach with those of a model based upon the deactivation mechanism. Using a continuous stirred tank reactor as an example, we show t...

  15. Influence of Instruments Used in Root Canal Preparation on Amount of Apically Extruded Debris.

    Science.gov (United States)

    Karataş, Ertuğrul; Ersoy, İbrahim; Gündüz, Hicran Ateş; Uygun, Ahmet Demirhan; Kol, Elif; Çakıcı, Fatih

    2016-08-01

    The aim of the present study was to compare the effects of ProTaper Gold, WaveOne Gold, ProTaper Universal, and WaveOne instruments on the amount of apically extruded debris. Eighty mandibular premolar teeth with straight root canals were selected and assigned to four groups (n = 20). The root canals were instrumented using ProTaper Gold, WaveOne Gold, ProTaper Universal, and WaveOne systems. Eppendorf tubes containing apically extruded debris were weighed three times, and mean values were calculated. The net mass of the extruded debris was calculated by subtracting the initial mass from the final mass. The groups were compared using one-way analysis of variance and Tukey's post hoc tests at a significance level of P < 0.05. The PTG group extruded less debris than the PTU group, and the WOG group extruded less debris than the WO group (P < 0.05). All the instrumentation systems tested in the present study were associated with apical extrusion of debris. PMID:26814380

  16. Pd Close Coupled Catalyst

    Institute of Scientific and Technical Information of China (English)

    Zhong Hua SHI; Mao Chu GONG; Yao Qiang CHEN

    2006-01-01

    A catalyst comprised novel high surface area alumina support was prepared to control emission of automobiles. The results showed that prepared catalyst could satisfy the requirements of a high performance close coupled catalyst for its good catalytic activity at low temperature and good stability at high temperature.

  17. Development of baked and extruded functional foods from metabolic syndrome specific ingredient mix.

    Science.gov (United States)

    Miglani, Neetu; Bains, Kiran; Kaur, Harpreet

    2015-09-01

    The study was aimed to develop baked and extruded functional foods from Metabolic Syndrome (MS) specific designed ingredient mixes with optimum amino acid makeup using key food ingredients with functional properties such as whole cereals, legumes, skimmed milk powder, along with flaxseeds and fenugreek seeds. Two cereals viz. barley and oats and four pulses viz. mung bean, cowpea, bengal gram and soybean were blended in different proportions in order to balance the limiting amino acid lysine in the wheat flour. Three products namely bread, extruded snack and noodles prepared from twenty five ingredient mixes. Six ingredient mixes of breads and four ingredient mixes each of extruded snack and noodles specifically designed for MS patients were organoleptically at par with control wheat flour products. The acceptable products had significantly (p ≤ 0.05) higher lysine, crude protein, ash and fibre and low carbohydrates in compare control whole wheat flour products, hence appropriate for MS patients. PMID:26345000

  18. Microstructural transformation of quasicrystalline AlFeCrTi extruded bars upon long thermal treatments

    International Nuclear Information System (INIS)

    Highlight: • Evolution upon heating of quasicrystalline AlFeCrTi alloy in bulk sample. • Warm extrusion of gas atomised powder particles. • Microstructural evolution of QC-AlFeCrTi extruded bars. - Abstract: Bulk Al93Fe3Cr2Ti2 bars extruded from gas atomised powder particles present a microstructure of an aluminium matrix reinforced with a spherical nanoquasicrystalline phase. In this work the evolution of the microstructure of Al93Fe3Cr2Ti2 extruded bars upon heating at 400 °C for up to 1000 h is investigated by means of X-ray diffraction, differential scanning calorimetry, scanning electron microscopy and transmission electron microscopy. According to our observations we propose that the quasicrystalline alloy evolves in two steps: a first step consists in the decomposition of the supersaturated solid solution of the matrix and the quasicrystals, and a second step in the transformation of the quasicrystals into the equilibrium phases

  19. Characterisation of the bonding zone of co-extruded aluminium-titanium-compounds

    Energy Technology Data Exchange (ETDEWEB)

    Grittner, N.; Schaper, M.; Bach, F.W. [Institut fuer Werkstoffkunde, Garbsen (Germany); Hehl, A. von; Hunkel, M.; Schimanski, K.; Zoch, H.W. [Stiftung Institut fuer Werkstofftechnik, Bremen (Germany); Stelling, O. [Parker Hannifin Manufacturing GmbH and Co. KG, Stuhr (Germany); Striewe, B.

    2012-04-15

    The combination of different metallic materials enables the design of lightweight structures with tailor-made properties at global as well as local scale and offers great potential for advanced solutions especially for the aircraft and automobile sector. However, after conventional fusion joining, e. g. after laser beam welding, heat affected zones, porosity or grain growth may occur and impair the local properties. In contrast, by solid-state joining techniques like co-extrusion these disadvantages can be avoided. Therefore co-extrusion exhibits an attractive solution for long products combining aluminium and titanium based alloys. Current investigations have been focused on the co-extrusion of aluminium and titanium, where titanium is the reinforcing element that is inserted in aluminium profiles. In the context of a current research project the formation of the intermetallic layer and the mechanical properties were investigated in detail. In addition to that the influence on the intermetallic layer and the mechanical properties on heat treatment were investigated. The mechanical properties were determined by tensile tests. The intermetallic layers were analysed with light optical microscope, scanning electron microscope and electron probe micro analysis. During the co-extruding an intermetallic layer with a thickness of 1 {mu}m to 3 {mu}m arises in the bonding zone between aluminium and titanium partner. Alloying elements from the aluminium alloy enrich in this layer. A subsequent heat treatment leads to an age hardening of the aluminium, however, it does not affect the layer thickness. The tensile tests specimen show different failure locations. The heat treatment leads to increased tensile strength values, but also to a decreased yield strength level. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Physicochemical characterization and drug-release properties of celecoxib hot-melt extruded glass solutions.

    Science.gov (United States)

    Andrews, Gavin P; Abu-Diak, Osama; Kusmanto, Febe; Hornsby, Peter; Hui, Zhai; Jones, David S

    2010-11-01

    The interest in hot-melt extrusion (HME) as a drug delivery technology for the production of glass solutions is growing rapidly. HME glass solutions have a tendency to recrystallize during storage and also typically have a very dense structure, restricting the ingress of dissolution fluid and retarding drug release. In this study, we have used HME to manufacture glass solutions containing celecoxib (CX) and polyvinylpyrrolidone (PVP) and have assessed the use of supercritical carbon dioxide (scCO2) as a pore-forming agent to enhance drug release. Differential scanning calorimetry confirmed the formation of glass solutions following extrusion. All extrudates exhibited a single glass transition temperature (Tg), positioned between the Tg values of CX and PVP. The instability of glass solutions is a significant problem during storage. Stabilization may be improved through the appropriate choice of excipient to facilitate drug–polymer interactions. The Gordon–Taylor equation showed that the Tg values of all extrudates expected on ideal mixing were lower than those observed experimentally. This may be indicative of drug–polymer interactions that decrease free volume and elevate the Tg. Molecular interactions between CX and PVP were further confirmed using Fourier transform infrared and Raman spectroscopy. Storage stability of the extrudates was shown to be dependent on drug loading. Samples containing a higher CX loading were less stable, which we ascribed to decreased Tg and hence increased mobility within the drug–polymer matrix. The solubility of CX was improved through the formulation of extruded glass solutions, but release rate was relatively slow. Exposure of extrudates to scCO2 had no effect on the solid-state properties of CX but did produce a highly porous structure. The drug-release rate from extrudates after scCO2 exposure was significantly higher. PMID:21072971

  1. Effect of use of extruded corn in broiler feed on yield and meat quality

    Directory of Open Access Journals (Sweden)

    Okanović Đorđe

    2012-01-01

    Full Text Available The objective of these investigations was to examine the efficacy of the use of extruded feed in the diet of broiler chicks. The procedure of extruding corn causes significant physical-chemical changes in the kernel structure, which increases the nutritive value as the nutritive matter in the kernel becomes more readily available to the enzymes of the animal’s digestive tract. This procedure also increases hygiene safety as well as the sensory characteristics (taste of the feed. Investigations were carried out on 3000 chicks of the Ross 308 hybrid, which were divided into an experimental and a control group. The fattening period lasted 49 days. The composition of the broiler mix was identical in both groups, with extruded corn being used in the mix for the control group (O. Broilers fed the mix with extruded corn (O showed faster growth, lower mortality (20:96 and better feed conversion (2.04:2,13 kg/kg in comparison with the control group (K. Broilers of the experimental group (O also realized greater mass of the breast (696.6:657.6 g and legs (569.2:528.2 g, as well as a greater meat percentage in the breast and legs. The diet with extruded corn also resulted in an improved nutritive quality of the broiler meat (higher protein content and lower content of free lipids in broiler meat. The meat of broilers fed the mix with extruded corn (O was found to contain a higher protein content (23.35:22.58% in the breast, and in the legs (18.26:17.67%, and a lower content of free lipids (1,.40:2.42% in the breast, and in the legs (5.87:9.24% in comparison with the meat of broilers of the control group (K. [Projekat Ministarstva nauke Republike Srbije, br. 46012

  2. Assessment of apically extruded debris and irrigant produced by different nickel-titanium instrument systems

    Directory of Open Access Journals (Sweden)

    Ebru KÜÇÜKYILMAZ

    2015-01-01

    Full Text Available The aim of this study was to evaluate the preparation time and the amounts of apically extruded debris and irrigant using different nickel-titanium instrumentation systems. Forty-five extracted single-rooted mandibular premolar teeth were selected and divided into three groups. The root canals were instrumented according to the manufacturers’ instructions, using a reciprocating single-file system, a single-file rotary system and a multiple-file rotary system. Bidistilled water was used as the irrigant solution. The apically extruded debris and irrigant were collected into preweighed Eppendorf tubes. The amounts of extruded debris and irrigant were assessed with a precision micro-balance. The Eppendorf tubes were incubated at 37°C for 15 days. After the incubation period, they were weighed again to assess the debris extrusion. The time required to prepare the canals was also recorded. The results were statistically analyzed using MANOVA and Bonferroni’s adjustment. Considering the apically extruded debris and irrigant, there were no statistically significant differences among the groups (p > 0.05. The Reciproc group produced the highest debris (0.000632 ± 0.000162 gr and irrigant (0.844587 ± 0.437814 ml extrusion values. While the least extruded debris was observed with OneShape (0,000431 ± 0,000171 gr, the least extruded irrigant was observed with ProTaper system (0.564147 ± 0.370596 ml. Instrumentation was faster using the Reciproc than the other two instruments (70.27 ± 13.38 s (p < 0.05. All of the instrumentation systems used in this study produced apical debris and irrigant extrusion. The reciprocating single-file system tended to produce more debris and irrigant extrusion, compared with the rotary systems. Considering the preparation time, the single-file systems appeared to be advantageous due to their working time.

  3. Design of heterogeneous catalysts

    DEFF Research Database (Denmark)

    Frey, Anne Mette

    was inspired by a computational screening, suggesting that alloys such as Ni-Fe, Co-Ni, and Co-Fe should show superior activity to the industrially used nickel catalyst. Especially the Ni-Fe system was considered to be interesting, since such alloy catalysts should be both more active and cheaper than...... turned out to work well, and the best catalyst prepared had a C5+ yield almost a factor of two higher than a standard air calcined Co catalyst. In the NH3-SCR reaction it is desirable to develop an active and stable catalyst for NOx removal in automotive applications, since the traditionally used...

  4. A new centrifuge pellet injector with a screw extruder for steady state fuelling

    International Nuclear Information System (INIS)

    A new conceptual design of a centrifuge injector for steady state plasma refuelling by solid hydrogen isotope pellets is presented and discussed. The apparatus has three new components: a screw extruder for continuous pellet production, a new rotating curved barrel for pellet acceleration, whose entrance section is placed on the axis of the centrifuge rotor, and a new pellet chopping unit. In preliminary tests, the screw extruder with the pellet chopping unit delivered a series of about 10,000 deuterium pellets of 2 mm in size (at the range up to 15 Hz and velocities 100-150 m/s) into the curved barrel with a 99% reliability. (author)

  5. Calibration of a Numerical Model for Heat Transfer and Fluid Flow in an Extruder

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Pedersen, David Bue; Nielsen, Jakob Skov;

    2016-01-01

    This paper discusses experiments performed in order to validate simulations on a fused deposition modelling (FDM) extruder. The nozzle has been simulated in terms of heat transfer and fluid flow. In order to calibrate and validate these simulations, experiments were performed giving a significant...... look into the physical behaviour of the nozzle, heating and cooling systems. Experiments on the model were performed at different sub-mm diameters of the extruder. Physical parameters of the model – especially temperature dependent parameters – were set into analytical relationships in order to receive...

  6. Effect of extruded fodder on biochemical and haematological parameters of Standardbred horses under training conditions

    OpenAIRE

    HÄRTLOVA, Helena; REHAK, Dalibor; SEDMİKOVA, Markéta; MENDLİK, Jaroslav; KRALOVA, Jana

    2010-01-01

    The aim of this study was to examine whether feeding of extruded fodder can improve the energy metabolism of horses under training conditions. The experiment was performed on 12 clinically healthy Standardbred horses (6 horses in the control group and 6 horses in the experimental group). The diet of the horses was based on oats, barley, meadow hay, and a supplement of vitamins and minerals. The diet of the experimental group (6 horses) was supplemented with 1.25 kg of extruded fodder that rep...

  7. Modelling extrudate expansion in a twin-screw food extrusion cooking process through dimensional analysis methodology

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    and temperature, are formed to model the extrusion process from dimensional analysis. The model is evaluated with experimental data for extrusion of whole wheat flour and fish feed. The average deviations of the model correlations are 5.9% and 9% based on experimental data for the whole wheat flour......A new phenomenological model is proposed to correlate extrudate expansion and extruder operation parameters in a twin-screw food extrusion cooking process. Buckingham's pi dimensional analysis method is applied to establish the model. Three dimensionless groups, i.e. pump efficiency, water content...

  8. Effect of Apple and Rosehip Pomaces on Colour, Total Phenolics and Antioxidant Activity of Corn Extruded Snacks

    Directory of Open Access Journals (Sweden)

    Drożdż Wioletta

    2014-09-01

    Full Text Available Extrusion cooking technology was applied for obtaining corn extrudates fortified with various level (10-20% of rosehip pomace powder or apple pomace powder. The total polyphenols content, antioxidant activities (ABTS, organoleptic properties and colour of the extrudates were determined.

  9. Real-time in vitro dissolution of 5-aminosalicylic acid from single ethyl cellulose coated extrudates studied by UV imaging

    DEFF Research Database (Denmark)

    Gaunø, Mette Høg; Vilhelmsen, Thomas; Larsen, Crilles Casper; Bøtker, Johan Peter; Wittendorff, Jørgen; Rantanen, Jukka; Ostergaard, Jesper

    2013-01-01

    The purpose of this study was to investigate the in vitro release of 5-aminosalicylic acid from single extrudates by UV imaging and to explore the technique as a visualization tool for detecting film coating defects on extrudates coated with a thin ethyl cellulose layer. 5-Aminosalicylic acid ext...

  10. Influência do envelhecimento de catalisadores Ziegler-Natta à base de neodímio sobre a polimerização de 1,3-butadieno Influence of ageing of neodymium based Ziegler-Natta catalyst on butadiene polymerization

    Directory of Open Access Journals (Sweden)

    Ivana L. Mello

    2007-03-01

    Full Text Available Catalisadores envelhecidos em diferentes tempos (0, 5, 15, 40, 80 e 160 dias e diferentes temperaturas (10, 25 e 40 °C foram testados na polimerização 1,4-cis do 1,3-butadieno. Avaliou-se a atividade catalítica bem como as características do polímero obtido (massa molecular e microestrutura. Os resultados encontrados mostraram que a variação nas condições de envelhecimento dos catalisadores não influenciou a microestrutura do polímero. O teor de unidades 1,4-cis permaneceu em torno de 98%, de unidades 1,4-trans em torno de 1,4% e de unidades vinílicas em 0,6%. Entretanto, reações utilizando os catalisadores envelhecidos por 40 dias forneceram polibutadieno com maior massa molecular do que os demais catalisadores. Verificou-se também, uma tendência de maiores conversões das polimerizações com os catalisadores envelhecidos a 25 °C.Catalysts aged for different time periods (0, 5, 15, 40, 80 and 160 days and different temperatures (10, 25 and 40 °C were tested in the cis-1,4 polymerization of 1,3-butadiene. The catalytic activity and polymer characteristics (molecular weight and microstructure were evaluated. The results showed that the catalyst ageing did not affect the polymer microstructure. The cis-1,4 content remained at 98%, trans-1,4 at 1,4% and vinyl units at 0,6%. However, the catalysts aged for 40 days produced polybutadienes with higher molecular weight. Also observed was a tendency to an increased polymerization conversion by the catalysts aged at 25 °C.

  11. Texture Evolution and Twinning During the Expansion of Hot Extruded AZ31 + Sr Seamless Tubes

    Science.gov (United States)

    Sadeghi, Alireza; Martin, Étienne; Pekguleryuz, Mihriban

    2014-12-01

    Seamless tubes of AZ31, AZ31 + 0.4, and 0.8 wt pctSr were extruded at elevated temperatures. By compressing pure copper inserts inside the tubes, the extruded tubes were expanded at room and elevated temperatures [373 K and 473 K (100 °C and 200 °C)]. Microstructural examinations reveal the formation of twining in the as-extruded and expanded tubes. The amount of twinning decreased with increasing level of Sr in the expanded microstructures as a result of grain refinement and of decreasing Al in solution that facilitates dislocation motion. During expansion at room temperature, AZ31 shows higher elongation and lower strength than the alloys containing Sr. At 473 K (200 °C), compared to the lower temperatures, the Sr containing alloys exhibit lower flow stress and no fracture in the strain range investigated (40 pct reduction in cylinder height). The textures of the extruded alloys contain two main components named as RD ( c-axis parallel to the radial direction) and HD ( c-axis parallel to the hoop direction) based on their orientation with the sample coordinates. During expansion, extension twinning in the HD grains reorients the lattice to strengthen the RD and form a new ED ( c-axis parallel to the extrusion direction) component. By increasing the temperature or level of Sr, the ED component is weakened due to the decrease in twinning. During expansion, the RD grains undergo contraction and double twining which reduce the overall texture strength.

  12. Gluten-Free Bread Production by the Corn Meal and Soybean Flour Extruded Blend Usage

    Directory of Open Access Journals (Sweden)

    Duška Ćurić

    2007-09-01

    Full Text Available The most common disease caused by cereal protein ingestion is celiac disease. This can be treated only by a diet that excludes all foods containing wheat, barley, rye and oat proteins. Corn meal (CM and defatted soybean fl our (DSF blend processed by High Temperature Short Time (HTST extrusion cooking for gluten-free bread production was investigated. Corn meal and soybean fl our were extruded in three different proportions (w/w: 100 CM / 0 DSF; 87.5 CM / 12.5 DSF; 75 CM / 25 DS. After milling extruded fl our blends were combined in a 1:1 mixture with rice fl our for gluten-free bread making. Rheological properties of dough (viscosity and water absorption, baking characteristics, dough and bread yield, were investigated with or without different hydrocolloids addition. Protein content and sensory properties of the gluten-free breads were determined. Bread produced with extruded blend of 75 CM / 25 DSF with addition of guar gum had the biggest volume, the best crumb elasticity, softness and porosity. All bread samples made of extruded flours had high protein content (more than 10% db and good sensory properties.

  13. Characterization of peptides found in unprocessed and extruded amaranth (Amaranthus hypochondriacus) pepsin/pancreatin hydrolysates.

    Science.gov (United States)

    Montoya-Rodríguez, Alvaro; Milán-Carrillo, Jorge; Reyes-Moreno, Cuauhtémoc; González de Mejía, Elvira

    2015-01-01

    The objectives of this study were to characterize peptides found in unprocessed amaranth hydrolysates (UAH) and extruded amaranth hydrolysates (EAH) and to determine the effect of the hydrolysis time on the profile of peptides produced. Amaranth grain was extruded in a single screw extruder at 125 °C of extrusion temperature and 130 rpm of screw speed. Unprocessed and extruded amaranth flour were hydrolyzed with pepsin/pancreatin enzymes following a kinetic at 10, 25, 60, 90, 120 and 180 min for each enzyme. After 180 min of pepsin hydrolysis, aliquots were taken at each time during pancreatin hydrolysis to characterize the hydrolysates by MALDI-TOF/MS-MS. Molecular masses (MM) (527, 567, 802, 984, 1295, 1545, 2034 and 2064 Da) of peptides appeared consistently during hydrolysis, showing high intensity at 10 min (2064 Da), 120 min (802 Da) and 180 min (567 Da) in UAH. EAH showed high intensity at 10 min (2034 Da) and 120 min (984, 1295 and 1545 Da). Extrusion produced more peptides with MM lower than 1000 Da immediately after 10 min of hydrolysis. Hydrolysis time impacted on the peptide profile, as longer the time lower the MM in both amaranth hydrolysates. Sequences obtained were analyzed for their biological activity at BIOPEP, showing important inhibitory activities related to chronic diseases. These peptides could be used as a food ingredient/supplement in a healthy diet to prevent the risk to develop chronic diseases. PMID:25894223

  14. Corrosion and mechanical properties of hot-extruded AZ31 magnesium alloys

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AZ31 magnesium alloys were hot-extruded at 573 K and 623 K with extrusion ratio (λ) of 20, 35 and 50. The corrosion and mechanical behavior of hot-extruded AZ31 were studied by galvanic tests and tensile tests. The microstructures of the studied AZ31 alloys were also investigated with optical microscope. The results show that, compared with the as-cast AZ31 alloy, the corrosion potentials of all hot-extruded AZ31 alloys are increased by 60 mV. Moreover, at the extrusion temperature of 623 K, the galvanic current of AZ31 alloy decreases with increasing extrusion and the galvanic corrosion resistance is increased by 10% with the extrusion ratio of 50. In addition, the tensile strength and elongation of the extruded alloys are significantly enhanced by about 20% and 140%, respectively. The improvement of corrosion resistance and obvious increasing of mechanical properties of AZ31 alloys by hot-extrusion are ascribed to grain refinement and microstructural modification together with the homogeneous distribution of intermetallie phases throughout the matrix.

  15. Wheat gluten in extruded fish feed: Effects on morphology and on physical and functional properties

    NARCIS (Netherlands)

    Draganovic, V.; Goot, van der A.J.; Boom, R.M.; Jonkers, J.

    2013-01-01

    This article focuses on understanding the role of vital wheat gluten on the structural parameters of extruded fish feed and its correlation to the physical and functional properties. Gluten–soy protein concentrate blends with five gluten concentrations (0–200 g kg-1) were produced. An abrupt reducti

  16. Quench sensitivity of hot extruded 6061-T6 and 6069-T6 aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Bergsma, S C; Kassner, M E; Li, X; Rosen, R S

    2000-08-08

    The purpose of this study is to investigate the quench sensitivity of mechanical properties of hot extruded 6061 and 6069 aluminum alloys. The relationship between mechanical properties and quench delzty time at various temperatures between 200-500 C was determined. It was concluded that the 6069-T6 was somewhat more quench sensitive than 6061, which may be consistent with the composition difference.

  17. Ethanol Production from Extruded Thermoplastic Maize Meal by High Gravity Fermentation with Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    Mayeli Peralta-Contreras

    2014-01-01

    Full Text Available A comparative study of extruded and ground maize meals as raw materials for the production of regular (12°P and high gravity (20°P worts was devised. Extruded water solubility index (WSI was higher (9.8 percentage units and crude fat was lower (2.64 percentage units compared to ground maize. Free-amino nitrogen compounds (FAN, pH, and glucose were evaluated in regular and high gravity worts produced from ground or extruded maize. Extrusion improved glucose content and ethanol yield. In 20°P mashes, extrusion is enhanced by 2.14% initial glucose compared with regular ground mashes. The 12°P and 20°P extruded treatments averaged 12.2% and 8.4% higher ethanol, respectively, compared to the uncooked counterpart. The 20°P worts fermented with Zymomonas mobilis produced 9.56% more ethanol than the 12°P counterpart. The results show that the combination of extrusion and fermentation of 20°P worts improved ethanol yield per kg flour until 20.93%. This pretreatment stimulates Z. mobilis fermentation efficiency.

  18. Mechanical-Acoustic and Sensory Evaluations of Corn Starch-Whey Protein Isolate Extrudates

    Science.gov (United States)

    To study the mechanism that relates sensory perception of brittle food foams to their mechanical and acoustic properties during crushing, corn starch was extruded with four levels (0, 6, 12, and 18%) of whey protein isolate (WPI) and two levels of in-barrel moisture (23 and 27%). Texture of the exp...

  19. Characterization of Peptides Found in Unprocessed and Extruded Amaranth (Amaranthus hypochondriacus Pepsin/Pancreatin Hydrolysates

    Directory of Open Access Journals (Sweden)

    Alvaro Montoya-Rodríguez

    2015-04-01

    Full Text Available The objectives of this study were to characterize peptides found in unprocessed amaranth hydrolysates (UAH and extruded amaranth hydrolysates (EAH and to determine the effect of the hydrolysis time on the profile of peptides produced. Amaranth grain was extruded in a single screw extruder at 125 °C of extrusion temperature and 130 rpm of screw speed. Unprocessed and extruded amaranth flour were hydrolyzed with pepsin/pancreatin enzymes following a kinetic at 10, 25, 60, 90, 120 and 180 min for each enzyme. After 180 min of pepsin hydrolysis, aliquots were taken at each time during pancreatin hydrolysis to characterize the hydrolysates by MALDI-TOF/MS-MS. Molecular masses (MM (527, 567, 802, 984, 1295, 1545, 2034 and 2064 Da of peptides appeared consistently during hydrolysis, showing high intensity at 10 min (2064 Da, 120 min (802 Da and 180 min (567 Da in UAH. EAH showed high intensity at 10 min (2034 Da and 120 min (984, 1295 and 1545 Da. Extrusion produced more peptides with MM lower than 1000 Da immediately after 10 min of hydrolysis. Hydrolysis time impacted on the peptide profile, as longer the time lower the MM in both amaranth hydrolysates. Sequences obtained were analyzed for their biological activity at BIOPEP, showing important inhibitory activities related to chronic diseases. These peptides could be used as a food ingredient/supplement in a healthy diet to prevent the risk to develop chronic diseases.

  20. Application of extruded broken bean flour for formulation of gluten-free cake blends

    Directory of Open Access Journals (Sweden)

    Luciana de Oliveira Froes Gomes

    2015-06-01

    Full Text Available The aim of this study was to determine the physical and microbiological characteristics of extruded broken beans flour, in addition to developing mixtures for gluten-free cake with these flours, evaluating their technological and sensory quality. Gluten-free formulations were prepared with 45%, 60% and 75% of extruded broken beans. All analyzes of the flours and mixtures for cakes were performed according to standard techniques found in the literature. Sensory analyzes of cakes applied the 9-point structured hedonic scale. Results were submitted to variance analysis and comparison of means test (Tukey, p<0.05. The use of extruded broken beans improved the water absorbed and water solubility index of the mixtures for gluten-free cake, and for the lower viscosity and retrogradation when compared to the standard formulation. All cakes were accepted (rate ≥ 7 for all the analyzed attributes. From the technological and sensory standpoints, the development of gluten-free cake mixtures is feasible with up to 75% of extruded broken beans.

  1. Chemical and toxicological evaluation of fumonisin B1 in extruded corn grits.

    Science.gov (United States)

    Extrusion cooking reduces fumonisin concentrations in corn but its effect on fumonisin toxicity is unknown. Batches of corn grits were contaminated by spiking with fumonisin B1 (FB1) (SG, 43 ppm) or by fermentation (FG1, 46 ppm FB1; FG2 48 ppm FB1) and then extruded with and without the addition of ...

  2. Characterisation and potential application of pineapple pomace in an extruded product for fibre enhancement.

    Science.gov (United States)

    Selani, Miriam Mabel; Brazaca, Solange Guidolin Canniatti; Dos Santos Dias, Carlos Tadeu; Ratnayake, Wajira S; Flores, Rolando A; Bianchini, Andreia

    2014-11-15

    This study characterised pineapple pomace (PP) and evaluated its application in extrusion to enhance fibre content of the final product. The pomace had low fat (0.61%) and high dietary fibre (45.22%), showing its potential for fibre enrichment of nutritionally poor products, as some extruded snacks. Results also showed low microbiological counts, water activity, and pH indicating good microbiological quality and low risk of physicochemical deterioration. During extrusion, pomace (0%, 10.5% and 21%), moisture (14%, 15% and 16%) and temperature (140 and 160°C) were evaluated. The PP addition decreased expansion and luminosity; while increasing redness of the extrudates compared to the control (0% pomace/14% moisture/140°C). When hardness, yellowness, water absorption, and bulk density were compared to the control, there was no effect (p>0.05) of 10.5% PP addition on the extrudates, indicating that, at this level, PP could be added without affecting the properties of the final extruded product. PMID:24912691

  3. Effect of twin-screw extrusion parameters on mechanical hardness of direct-expanded extrudates

    Indian Academy of Sciences (India)

    M Brnčić; B Tripalo; D Ježek; D Semenski; N Drvar; M Ukrainczyk

    2006-10-01

    Mechanical properties of cereal (starch-based) extrudates are perceived by the final consumer as criteria of quality. We investigate one of the important characteristics of extrudates, mechanical hardness, which is one of the main texture parameters. Texture quality has an influence on taste sensory evaluation, and thus on the acceptability of the product. Characteristics that have great influence on acceptability are crispness, elasticity, hardness and softness. These attributes are narrowly related to, and affected by, the process parameters. A 2-level–4-factor factorial experimental design was used to investigate the influence of temperature of expansion, screw speed, feed moisture content and feed rate, and their interactions, on the mechanical hardness of extrudates. Feed moisture content, screw speed and temperature are found to influence, while feed rate does not have significant effect on extrudate hardness. Mechanical properties of specimens were measured by means of compression testing, based on the concept of nominal stress, using a universal testing machine and special grips that were constructed for this purpose.

  4. A mathematical model describing the solid conveying and melting behavior of planetary roller extruders

    Science.gov (United States)

    Rudloff, J.; Lang, M.; Kretschmer, K.; Heidemeyer, P.; Bastian, M.; Koch, M.

    2014-05-01

    Due to increased quality requirements and the trend to cost reduction by process optimization, the modeling of plastic processing by means of simulation software becomes more and more important to predict process behavior. Most tools are based on a physical analysis of the process conditions and a reflection of those in a mathematical model, either based on FE methods or an approach to approximation or complete analytical models. First models were published for planetary roller extruders. However, these models deal primarily with the melt conveying behavior and have not yet been developed for the melting process which in many cases is critical to address homogenization features of such machines in the melt phase. This paper presents an approach to calculate the melting degree along the barrel of a planetary roller extruder. Therefore, models that are used to describe the melting process of single and twin screw extruders are adjusted to the conditions in the planetary roller extruder. At first the relevant process was divided in the three steps solid conveying, melting initiation and melting propagation. The solid conveying is described by the Archimedes solid conveying model. In order to estimate the melting initiation the solid particles temperature increase was used for partial filled sections. Further, it was assumed that the melting cannot start later than at the point where the extruder flow channels are fully filled for the first time. The melting propagation was described by a modified disperse melting model. The developed models were implemented into a simulation tool. The models were verified by experimental investigations. A comparison between simulated results and experimental data shows a good agreement.

  5. Corn types with different nutritional profiles, extruded or not, on piglets (6 to 15 kg feeding

    Directory of Open Access Journals (Sweden)

    Gisele Cristina de Oliveira

    2011-11-01

    Full Text Available Two experiments were carried out to determine the nutritional value and verify piglets' performance in the nursery phase fed with diets containing common corn (CC, extruded common corn (ECC, high-lysine corn (HLC, extruded high-lysine corn (EHLC, high-oil corn (HOC and extruded high-oil corn (EHOC. In the total digestibility trial 14 barrows averaging 6.49 ± 0.16 kg initial body weight were allotted in metabolism cages, distributed in a randomized design with seven diets, six replicates, and one piglet per experimental unit. The values of digestible energy (DE, as well as metabolizable energy (ME as-fed basis for CC, ECC, HLC, EHLC, HOC and EHOC were: 3,428 and 3,327 kcal/kg; 3,439 and 3,355 kcal/kg; 3,533 and 3,414 kcal/kg; 3,515 and 3,427 kcal/kg; 3,483 and 3,377 kcal/kg; 3,585 and 3,482 kcal/kg, respectively. In the performance experiment, 84 piglets, weaned at 21 days old, initial live weight of 6.06 ± 0.54 kg were used. Animals were allotted in a completely randomized design in a 3 × 2 factorial arrangement, using three types of corn (CC, HLC and HOC, two forms of processing (processed or not by extrusion, seven replicates and two piglets per experimental unit. Six diets containing CC, ECC, HLC, EHLC, HOC and EHOC were studied. There were no advantages in the digestibility and performance by extruding the types of corn with different nutritional profiles, for their use in commercial diets for piglets. The results of the two experiments emphasize the importance of segregating the types of corn, extruded or not, in their real chemical and energetic composition as well as the values of true digestible amino acids for the formulation of piglet diets in the nursery phase.

  6. Resin Catalyst Hybrids

    Institute of Scientific and Technical Information of China (English)

    S. Asaoka

    2005-01-01

    @@ 1Introduction: What are resin catalyst hybrids? There are typically two types of resin catalyst. One is acidic resin which representative is polystyrene sulfonic acid. The other is basic resin which is availed as metal complex support. The objective items of this study on resin catalyst are consisting of pellet hybrid, equilibrium hybrid and function hybrid of acid and base,as shown in Fig. 1[1-5].

  7. Novel Oxygen Storage Components Promoted Palladium Catalysts for Emission Control in Natural Gas Powered Engines

    Institute of Scientific and Technical Information of China (English)

    Bin ZHAO; Mao Chu GONG; Xue Song FENG; Yong Yue LUO; Yao Qiang CHEN

    2005-01-01

    A three-way catalyst comprised novel oxygen storage components for emission control in natural gas powered engines was prepared. The addition of novel oxygen storage components to the Pd/γ-A12O3 catalysts resulted in improved activities of the fresh and aged catalyst by lowering the light-off temperature for methane in natural gas engines exhaust.

  8. TECHNOLOGY DEVELOPMENT FOR IRON FISCHER-TROPSCH CATALYSTS

    Energy Technology Data Exchange (ETDEWEB)

    Davis, B.H.

    1998-07-22

    The goal of the proposed work described in this Final Report was the development of iron-based Fischer-Tropsch catalysts that combined high activity, selectivity and life with physical robustness for slurry phase reactors that will produce either low-alpha or high-alpha products. The work described here has optimized the catalyst composition and pretreatment operation for a low-alpha catalyst. In parallel, work has been conducted to design a high-alpha iron catalyst that is suitable for slurry phase synthesis. Studies have been conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors have been studied at the laboratory scale. Catalyst performance has been determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  9. Catalyst for Ammonia Oxidation

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a bimetallic catalyst for ammonia oxidation, a method for producing a bimetallic catalyst for ammonia oxidation and a method for tuning the catalytic activity of a transition metal. By depositing an overlayer of less catalytic active metal onto a more catalytic...

  10. Alloy catalyst material

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a novel alloy catalyst material for use in the synthesis of hydrogen peroxide from oxygen and hydrogen, or from oxygen and water. The present invention also relates to a cathode and an electrochemical cell comprising the novel catalyst material, and the process use...

  11. Heterogeneous hydrogenation catalysts

    International Nuclear Information System (INIS)

    The main types of heterogeneous catalysts used for hydrogenation, the methods for their preparation, and the structure and chemistry of their surfaces are considered, as well as the catalytic activity and the mechanism of action in the hydrogenation of unsaturated and aromatic compounds, of CO, and of carbonyl compounds and in the hydrorefining of fuels. Chief attention is paid to supported Ni catalysts, to the methods for their preparation and physicochemical studies, and to the development of novel catalytic systems through modification. A novel type of catalyst for hydrogenation, viz. metal carbides, is described. Some aspects of the mechanochemical treatment of hydrogenation catalysts, including in situ methods, are discussed. Sulfide catalysts for hydrotreating are also discussed in detail. The bibliography includes 340 references.

  12. Catalysts, methods of making catalysts, and methods of use

    KAUST Repository

    Renard, Laetitia

    2014-03-06

    Embodiments of the present disclosure provide for catalysts, methods of making catalysts, methods of using catalysts, and the like. In an embodiment, the method of making the catalysts can be performed in a single step with a metal nanoparticle precursor and a metal oxide precursor, where a separate stabilizing agent is not needed.

  13. Strengthening mechanisms of indirect-extruded Mg–Sn based alloys at room temperature

    Directory of Open Access Journals (Sweden)

    Wei Li Cheng

    2014-12-01

    Full Text Available The strength of a material is dependent on how dislocations in its crystal lattice can be easily propagated. These dislocations create stress fields within the material depending on their intrinsic character. Generally, the following strengthening mechanisms are relevant in wrought magnesium materials tested at room temperature: fine-grain strengthening, precipitate strengthening and solid solution strengthening as well as texture strengthening. The indirect-extruded Mg–8Sn (T8 and Mg–8Sn–1Al–1Zn (TAZ811 alloys present superior tensile properties compared to the commercial AZ31 alloy extruded in the same condition. The contributions to the strengthen of Mg–Sn based alloys made by four strengthening mechanisms were calculated quantitatively based on the microstructure characteristics, physical characteristics, thermomechanical analysis and interactions of alloying elements using AZ31 alloy as benchmark.

  14. Extruded soybean and flaxseed enhance fat composition of milk for Parmigiano-Reggiano cheese

    Directory of Open Access Journals (Sweden)

    Andrea Formigoni

    2010-01-01

    Full Text Available Twenty Friesian dairy cows were used in an experimental trial to study the effects of extruded full-fat soybean and flaxseed dietary supplementation, at the level authorized by Consorzio of Parmigiano-Reggiano cheese(CPRC feeding guidelines (1.0 and 0.4 kg/cow/day, on milk production and fatty acid composition. Diet was typically based on alfalfa and mixed hays and cereals. Compared with the concentrations before trial start, CLA and DHA were significantly increased by dietary treatment. These results confirm that the inclusion of extruded full-fat soybean and flaxseed, in the amount authorized by CPRC rules, in the diet of dairy cows is a possible strategy to enhance milk fat composition.

  15. The column strength of aluminum alloy 75S-T extruded shapes

    Science.gov (United States)

    Holt, Marshall; Leary, J R

    1946-01-01

    Because the tensile strength and tensile yield strength of alloy 75S-T are appreciably higher than those of the materials used in the tests leading to the use of the straight-line column curve, it appeared advisable to establish the curve of column strength by test rather than by extrapolation of relations determined empirically in the earlier tests. The object of this investigation was to determine the curve of column strength for extruded aluminum alloy 75S-T. In addition to three extruded shapes, a rolled-and-drawn round rod was included. Specimens of various lengths covering the range of effective slenderness ratios up to about 100 were tested.

  16. Cassava and turmeric flour blends as new raw materials to extruded snacks

    Directory of Open Access Journals (Sweden)

    Alessandra Mussato Spinello

    2014-02-01

    Full Text Available Short cooking time and ability to blend varieties of food ingredients have made extrusion cooking a medium for low-cost and nutritionally improved food products. The effect of moisture, extrusion temperature and amount of turmeric flour mixed with cassava flour on physical characteristic of puffed snacks was evaluated in this work. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Results showed effect of extrusion parameters on dependents variables. High expansion, low browning, low water solubility index, intermediate water absorption index and high crispness desirable characteristics to puffed snacks are obtained in conditions of 12% moisture, 5% turmeric flour, 105º C of temperature and 250 rpm of screw speed. These paper point to the potential still unexplored of the use of flours of cassava and turmeric as raw materials in the development of extruded puffed snacks.

  17. Effects of extruded corn on milk yield and composition and blood parameters in lactating dairy cows

    Directory of Open Access Journals (Sweden)

    Igino Andrighetto

    2010-01-01

    Full Text Available According to a 2x2 cross over design, fourteen Holstein dairy cows at 99±55 DIM were fed two diets containing 21.5% DM of either ground corn (GC or extruded corn (EC. Performance and metabolic profile were detected during the third week of each experimental period. DMI and milk yield were not affected by dietary treatments. Milk fat and protein percentage of EC diet were significantly (P<0.10 lower than those of GC diet. Probably the higher rumen degradability of starch from EC thesis modified the synthesis of specific fatty acids leading to a milk fat depression event. Diets did not influence blood parameters, except for lower values of total protein and glucose content in EC diet-fed cows. Results suggested that the dietary inclusion of extruded corn should not be used at the tested level of substitution.

  18. Enzymatic hydrolysis of steam exploded corncob residues after pretreatment in a twin-screw extruder

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2014-09-01

    Full Text Available A modified twin-screw extruder incorporated with a filtration device was used as a liquid/solid separator for xylose removal from steam exploded corncobs. A face centered central composite design was used to study the combined effects of various enzymatic hydrolysis process variables (enzyme loading, surfactant addition, and hydrolysis time with two differently extruded corncobs (7% xylose removal, 80% xylose removal on glucose conversion. The results showed that the extrusion process led to an increase in cellulose crystallinity, while structural changes could also be observed via SEM. A quadratic polynomial model was developed for predicting the glucose conversion and the fitted model provided an adequate approximation of the true response as verified by the analysis of variance (ANOVA.

  19. APPLICATION OF OAT, WHEAT AND RYE BRAN TO MODIFY NUTRITIONAL PROPERTIES, PHYSICAL AND SENSORY CHARACTERISTICS OF EXTRUDED CORN SNACKS

    Directory of Open Access Journals (Sweden)

    Agnieszka Makowska

    2015-12-01

    Full Text Available Background. Cereal products constitute the basis of the diet pyramid. While the consumption of such prod- ucts as bread decreases, the group of food which popularity increase is cereal snacks. Unfortunately, the dietary value of this group of foodstuffs is limited. Thus, different types of cereal bran may be added to the produced snacks to enhance their nutritive value. However, an addition of bran may have an adverse effect on quality attributes of products. Material and methods. Corn grits enriched with 20 and 40% oat, wheat and rye bran was extruded. Basic parameters determining the nutritive value, physical characteristics and sensory attributes of the six produced types of extrudates were measured and compared. Moreover, the effect of additives applied on viscosity of aqueous suspensions of the raw materials and extrudates under controlled conditions was measured using RVA. Results. The dietary value of snacks containing bran depends on the type and quantitative shares of the additives. The content of dietary fibre in produced extrudates ranged from 6.5 to 15.8%, including soluble dietary fibre at 2.1 to 3.7%. With an increase of bran content in extrudates, their expansion decreased, density increased and the colour of extrudates changed (reduced brightness, increased a*, decreased b*. In sensory evaluation the highest acceptability was given to extrudates with a 20% addition of oat bran, while the lowest was given for those with 40% wheat bran. Based on PCA results positive correlations were found between overall desirability and crispiness, porosity, taste, colour and expansion. Negative correlations between desir- ability and hardness and density of extrudates were observed. The additives and their level also had an effect on changes in viscosity of aqueous suspensions measured using RVA. However, no correlation was found between quality features of extrudates and values of attributes measured in the analysis of viscosity. Conclusion

  20. Shelf-Life of an Extruded Blend of Peanut, Soybean and Corn

    OpenAIRE

    C. A. Guzmán; V. S. Bustamante

    2000-01-01

    The Shelf-Life (SL) of peanut, soybean and corn blend extruded without (A) and with butylhydroxytoluol (B) and extract of Rosmarinum sp (C) was determined. Only B significativaly increased SL. In function of temperature would be defined by: A- SL = e -0.0465x + 5.1762, B- SL = e -0.0421x + 5.3332, C- SL = e -0.581x +5.626

  1. PERFORMANCE OF A MODIFIED EXTRUDER FOR POLYESTER FIBER PRODUCTION USING RECYCLED PET

    OpenAIRE

    J.C. Tapia-Picazo; A. García-Chávez; R. Gonzalez-Nuñez; Bonilla-Petriciolet, A.; G. Luna-Bárcenas; A. Champión-Coria; A. Alvarez-Castillo

    2014-01-01

    In this study, we report the design and results of the operation of a modified extrusion equipment with spinning fiber devices. The performance of the equipment has been evaluated by producing polyester fibers from dierent recycled poly(ethylene terephthalate) (PET) of pharma- and bottle-grade. Flow performance along the extruder length was modeled and the pressure was calculated at standard conditions and considering a flow change of +10% in these standard conditions. The variation of drop p...

  2. Effect of carbamazepine on viscoelastic properties and hot melt extrudability of Soluplus ®.

    Science.gov (United States)

    Gupta, Simerdeep Singh; Parikh, Tapan; Meena, Anuprabha K; Mahajan, Nidhi; Vitez, Imre; Serajuddin, Abu T M

    2015-01-15

    The purpose of this study was to apply viscoelastic properties of polymer and drug-polymer mixtures to determine processing conditions for the preparation of amorphous solid dispersion by melt extrusion. A poorly water-soluble drug, carbamazepine (CBZ), was mixed with Soluplus(®) as the carrier. Torque analysis using a melt extruder was performed at 10, 20 and 30% w/w drug concentrations and the effect of barrel temperature was studied. Viscosity of the mixtures either at fixed temperatures with different angular frequencies or as a function of temperature with the same frequency was studied using a rheometer. The viscosity of Soluplus(®) and the torque exerted on the twin screws decreased with the increase in CBZ concentration. The viscosity versus temperature plots for different CBZ concentrations were parallel to each other, without the drug melting transition, indicating complete drug-polymer miscibility. Thus, the drug-polymer mixtures could be extruded at temperature as low as 140°C with 10% w/w drug load, 135°C with 20% w/w drug and 125°C with 30% w/w drug, which were, respectively, ∼ 50°C, 55°C and 65°C below the melting point of 191°C for CBZ. The differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD) analyses of the binary mixtures extruded at 125-150°C showed absence of crystalline drug. A systematic study of miscibility and extrudability of drug-polymer mixtures by rheological and torque analysis as a function of temperature will help formulators select optimal melt extrusion processing conditions to develop solid dispersions. PMID:25448585

  3. Orientation-dependent microstructure and shear flow behavior of extruded Mg–Li–Zn alloys

    Energy Technology Data Exchange (ETDEWEB)

    Karami, M.; Mahmudi, R., E-mail: mahmudi@ut.ac.ir

    2015-06-11

    The microstructural and textural evolutions together with the orientation dependencies of mechanical properties of the extruded Mg–6Li–1Zn (LZ61), Mg–8Li–1Zn (LZ81) and Mg–12Li–1Zn (LZ121) alloys were investigated. The shear punch testing (SPT) method was employed to evaluate the room- and high-temperature (200–300 °C) mechanical anisotropy of the extruded materials. Microstructural analysis revealed that, despite a great discontinuous dynamic recrystallization (DDRX) occurred in the extrusion direction (ED) and normal direction (ND), the microstructural anisotropy was observed in all extruded materials, the effect which was more pronounced in the LZ81 alloy by developing banded structure in the ND condition. Textural studies in both hcp LZ61 and LZ81-α phase showed a fiber-type texture with the basal planes being parallel to the ED after extrusion. For the LZ81 alloy, however, the interfering presence of β phase affects the LZ81-α-phase texture by reducing the intensity of the maximum orientations of the basal and prismatic planes. Similar weakened bimodal type texture was formed in the bcc-structured LZ81-β phase, where some <110> poles were located parallel to the ED along with developing some other poles of a fiber-type character. It was also found that the abnormal grain growth might have been encouraged by the strong texture developed in the extruded LZ121 alloy. The SPT results indicated that the texture-dependent hcp LZ61 alloy showed higher shear strength in the ND condition than the ED condition, caused by the texture strengthening effect. As the Li content and deformation temperature increase, the texture dependence of strength properties, and thus, the mechanical anisotropy, decrease so that the LZ121-ND sample showed lower shear strength than the ED specimen due to the greater grain sizes achieved in the ND condition.

  4. Chitosan and chitosan/wheat gluten blends : properties of extrudates, solid films and bio-foams

    OpenAIRE

    Chen, Fei

    2015-01-01

    This thesis presents four different studis describing the characteristics and processing opportunities of two widely available biopolymers: chitosan and wheat gluten. The interest in these materials is mainly because they are bio-based and obtained as co- or by-products in the fuel and food sector In the first study, high solids content chitosan samples (60 wt.%) were successfully extruded. Chitosan extrusion has previously been reported but not chitosan extrusion with a high solids content, ...

  5. Performance, Egg Characteristics and Economic Impact of Laying Hens Fed Extruded Bakery Waste

    OpenAIRE

    I.M. Al-Ruqaie; M.S. Alamri; M.A. Alodan; T.M. Shafey; M.A. Abouheif; H.A. Al-Batshan

    2011-01-01

    An experiment was carried out to evaluate the effects of replacing corn with extruded Bakery Waste (BWP) in the diet of laying hens on the performance (feed intake, egg production, egg weight, egg mass and feed efficiency) and egg components (albumen, yolk and eggshell) and characteristics of eggshell (thickness and strength) and albumen (height and Haugh unit) and yolk (height and color (YH and YC)) and feed costs of egg production. Six isocaloric and isonitrogenous diets were formulat...

  6. A Protocol for Space Charge Measurements in Full-size HVDC Extruded Cables

    OpenAIRE

    Mazzanti, G.; G. Chen; Fothergill, J.; Hozumi, N; Li, J.; Marzinotto, M.; Mauseth, F.; Morshuis, P.; Reed, C.; Tzimas, A; Wu, K.

    2015-01-01

    This position paper, prepared by the IEEE DEIS HVDC Cable Systems Technical Committee, illustrates a protocol recommended for the measurement of space charges in full-size HVDC extruded cables during load cycle qualification tests (either prequalification load cycles or type test load cycles). The protocol accounts for the experimental practices of space charge measurements in the thick insulation of coaxial cables in terms of poling time, depolarization time, heating and cooling of spe...

  7. Changes in physical properties of extruded sour cassava starch and quinoa flour blend snacks

    OpenAIRE

    Lívia Giolo Taverna; Magali Leonel; Martha Maria Mischan

    2012-01-01

    Given the broad acceptance of sour cassava starch biscuits in Brazil and the nutritional quality of quinoa flour, this study aimed to evaluate the effect of extrusion temperature, screw speed, moisture, and amount of quinoa flour on the physical properties of puffed snacks. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Effects of moisture and amount of quinoa flour on the expansion index and specific volume of snacks...

  8. Flexural Behavior of Extruded DFRCC Panel and Reinforced Concrete Composite Slab

    OpenAIRE

    Chang-Geun Cho; Bang Yeon Lee; Yun Yong Kim; Byung-Chan Han; Seung-Jung Lee

    2012-01-01

    This paper presents a new reinforced concrete (RC) composite slab system by applying an extruded Ductile Fiber Reinforced Cement Composite (DFRCC) panel. In the proposed composite slab system, the DFRCC panel, which has ribs to allow for complete composite action, is manufactured by extrusion process; then, the longitudinal and transverse reinforcements, both at the bottom and the top, are placed, and finally the topping concrete is placed. In order to investigate the flexural behavior of the...

  9. Solute segregation and texture modification in an extruded magnesium alloy containing gadolinium

    International Nuclear Information System (INIS)

    The alloy Mg-1.5Gd has been extruded at different temperatures to produce two significantly different textures. At lower extrusion temperatures there was significant solute clustering in the matrix, coupled with segregation of solute to the grain boundaries. At higher temperatures these two phenomena were both less pronounced. It is suggested here that segregation of solute to the grain boundaries plays a significant role in the texture modification effect that rare earth elements have in magnesium alloys.

  10. Extrusion Conditions and Amylose Content Affect Physicochemical Properties of Extrudates Obtained from Brown Rice Grains

    Science.gov (United States)

    González, Rolando José; Pastor Cavada, Elena; Vioque Peña, Javier; Torres, Roberto Luis; De Greef, Dardo Mario; Drago, Silvina Rosa

    2013-01-01

    The utilization of whole grains in food formulations is nowadays recommended. Extrusion cooking allows obtaining precooked cereal products and a wide range of ready-to-eat foods. Two rice varieties having different amylose content (Fortuna 16% and Paso 144, 27%) were extruded using a Brabender single screw extruder. Factorial experimental design was used to study the effects of extrusion temperature (160, 175, and 190°C) and grits moisture content (14%, 16.5%, and 19%) on extrudate properties. Specific mechanical energy consumption (SMEC), radial expansion (E), specific volume (SV), water absorption (WA), and solubility (S) were determined on each extrudate sample. In general, Fortuna variety showed higher values of SMEC and S (703–409 versus 637–407 J/g; 33.0–21.0 versus 20.1–11.0%, resp.) than those of Paso 144; on the contrary SV (8.64–3.47 versus 8.27–4.53 mL/g) and WA tended to be lower (7.7–5.1 versus 8.4–6.6 mL/g). Both varieties showed similar values of expansion rate (3.60–2.18). Physical characteristics depended on extrusion conditions and rice variety used. The degree of cooking reached by Paso rice samples was lower than that obtained for Fortuna. It is suggested that the presence of germ and bran interfered with the cooking process, decreasing friction level and broadening residence time distribution. PMID:26904605

  11. Influence of the addition of extruded flours on rice bread quality

    OpenAIRE

    Martínez, Mario M.; Oliete, Bonastre; Román, Laura; Gómez, Manuel

    2014-01-01

    Producción Científica The extrusion may improve coeliac bread quality by modifying the functional properties of flour. This study investigates the influence of the substitution of 10% of rice flour by extruded rice flours (three intensities of treatment and two particle sizes) on the characteristics of gluten-free bread (specific volume and texture) at constant consistency. The microstructure and rheology of the doughs obtained and their behaviour during fermentation have also been analyse...

  12. Spontaneous Remission of a Big Subligamentous Extruded Disc Herniation: Case Report and Review of the Literature

    OpenAIRE

    Çitişli, Veli; İbrahimoğlu, Muhammet

    2015-01-01

    Spontaneous Regression of a Big Subligamentous Extruded Disc Herniation: Case Report And Review of The Literature The most efficient method for the treatment of lumbar disc herniation is still controversial. The most important aspect is the application of the suitable conservative or surgical treatment to the right patient at the right time. In lumbar disc herniation patients, one must not precipitate except for cases that require surgical indications as in cauda equina syndrome, evolutive mo...

  13. OPTIMISATION OF EXTRUDED POLYMER FOAM BY THE RESIDENT TIME DISTRIBUTION APPROACH

    OpenAIRE

    LEONARDI, Frederic; Larochette, Mathieu; Nasri, Djamel; Graebling, D.

    2008-01-01

    In this work, we used the Residence Time Distribution (RTD) to study the polystyrene foaming during an extrusion process. The extruder associated with a gear pump is simply and quantitatively described by three continuoustly stirred tank reactors with recycling loops and one plug-flow reactor. The blowing agent used is CO2 and its obtained by ther- mal decomposition of a chemical blowing agent (CBA). This approach allows to optimize the density of the foam in accordance with the CBA kinetic o...

  14. Melt-Extruded Eudragit® FS-Based Granules for Colonic Drug Delivery.

    Science.gov (United States)

    Zhang, Feng

    2016-02-01

    The purpose of this study is to characterize the properties of Eudragit® FS-based granules prepared using melt extrusion process for colonic drug delivery. 5-Aminosalicylic acid (5-ASA), theophylline, and diclofenac sodium were used as the model compounds. Drug and polymer blends were melt-extruded into thin rods using a single screw extruder. Drugs were found to be dispersed as crystalline particles in the granules. A hammer mill was used to reduce the extrudate into 16-40 mesh granules, which were mixed with lactose and filled into hard gelatin capsules. Three-stage dissolution testing performed using USP paddle method was used to simulate drug release in gastrointestinal tract. In this study, melt extrusion has been demonstrated to be a suitable process to prepare granules for colonic delivery of 5-amino salicylic acid. At 30% drug loading, less than 25% 5-ASA was released from melt-extruded granules of 20-30 mesh in the first two stages (0.1 N hydrochloric acid solution and phosphate buffer pH 6.8) of the dissolution testing. All 5-ASA was released within 4 h when dissolution medium was switched to phosphate buffer pH 7.4. Drug loading, granule size, and microenvironment pH induced by the solubilized drug were identified as the key factors controlling drug release. Granules prepared with melt extrusion demonstrated lower porosity, smaller pore size, and higher physical strength than those prepared with conventional compression process. Eudragit® FS was found to be stable even when processed at 200°C. PMID:26162974

  15. Physical and functional evaluation of extruded flours obtained from different rice genotypes

    Directory of Open Access Journals (Sweden)

    Fernanda Salamoni Becker

    2014-08-01

    Full Text Available The transformation of broken grains into native flours modified by extrusion is an alternative to add value to these co-products from the paddy rice processing. This study aimed to analyze the process of extrusion cooking on the physical and functional characteristics of extruded flours obtained from different rice genotypes (IRGA-417, BRS-Primavera and CNA-8502. The experimental design was completely randomized (3x2 factorial with four original replicates and analysis of variance to assess particle size, instrumental color parameters (L*, a* and b*, water absorption index (WAI, milk absorption index (MAI, oil absorption index (OAI, water solubility index (WSI and milk solubility index (MSI of rice flour. The extrusion process promoted changes in all physical and functional properties of rice flour, but only WSI and color parameters were influenced by genotype and by the industrial processing. Rice flours become darker, tending to a more reddish and yellow coloration after extrusion. Native and extruded rice flours of genotypes IRGA-417, BRS-Primavera and extruded rice flour of genotype CNA-8502 showed finer particles, while native flour of genotype CNA-8502 showed coarser particles. The extruded flours of IRGA-417 genotype obtained higher expansion and luminosity, and lower values of chroma a*, chroma b* and water solubility, while the BRS-Primavera higher values of chroma a* and b*, and lower luminosity and expansion, and CAN-8502 higher water solubility and lower expansion and value of chroma a*. The extrusion process led to flours with high water and milk absorption and solubility, low oil absorption and with potential for application in instant products, regardless of genotype.

  16. The influence of starch molecular mass on the properties of extruded thermoplastic starch

    OpenAIRE

    Vliegenthart, J. F. G.; van Soest, J.J.G.; Benes, K.; de Wit, D

    1996-01-01

    The mechanical properties of a low and a high molecular mass thermoplastic starch (TPS) were monitored at water contents in the range of 5–30% (w/w). The granular starches were plasticized by extrusion processing with glycerol and water. The low molecular mass starch was prepared by partial acid hydrolysis of potato starch. The extruded TPS materials were stored at 60% relative humidity for 12 months to level out differences in starch structure due to retrogradation. The water content was the...

  17. Effect of starch source, screw configuration and steam injection on physical quality and color development of extruded fish feed

    OpenAIRE

    Sitaula, Yogendra

    2012-01-01

    The study investigated the effect of starch sources, screw configuration, and steam injection on physical quality of extruded fish feed. Pellet durability, water stability and hardness were measured and analyzed. Four starch sources; pregelatinized potato starch, potato starch, whole wheat and wheat starch were used in the production of extruded fish feed. Three screw configuration types; polygon-2L, polygon-LR, and LRLR were used during production of feed. Similarly, steam injection and no s...

  18. Viability of Micro-Organisms Involved in Outbreaks of Bacterial Food Borne Diseases in Dry Extruded Pet Food

    OpenAIRE

    C. Adelantado; Lopez, S.(Instituto de F ısica Corpuscular (IFIC) and Departamento de Física Atómica, Molecular y Nuclear and Departamento de Ingeniería Electrónica and Instituto de Microelectrónica de Barcelona (IMB-CNM), University of Valencia and CSIC, Valencia, Spain); R. Inglada; L. Vilaseca; M.A. Calvo

    2008-01-01

    This study analyzed the viability of the main micro-organisms involved in outbreaks of bacterial food borne diseases together with two fungal strains experimentally inoculated into six different commercial dry extruded pet foods during six months. Growth of all micro-organisms analyzed decreased along the experimental period, indicating that dry extruded pet food is not an adequate substrate for microbial development and it is safe as pet food since most pathogenic micro-organisms did not ada...

  19. The thermo-mechano-chemical fractionation of sunflower whole plant in twin-screw extruder, an opportunity for its biorefinery

    OpenAIRE

    Evon, Philippe; Vandenbossche, Virginie; Pontalier, Pierre-Yves; Rigal, Luc

    2013-01-01

    Biorefinery of sunflower whole plant is conducted according to an aqueous process using a twin-screw extruder. Aqueous extraction of oil is looked upon as an environmentally cleaner alternative technology to solvent extraction. Twin-screw extruder carries out three unit operations continuously: conditioning and grinding of whole plant, liquid/solid extraction and liquid/solid separation. Extraction efficiency depends on screw speed, and input flow rates of whole plant and water. In best condi...

  20. Microstructures, mechanical and corrosion properties and biocompatibility of as extruded Mg–Mn–Zn–Nd alloys for biomedical applications

    International Nuclear Information System (INIS)

    Extruded Mg–1Mn–2Zn–xNd alloys (x = 0.5, 1.0, 1.5 mass %) have been developed for their potential use as biomaterials. The extrusion on the alloys was performed at temperature of 623 K with an extrusion ratio of 14.7 under an average extrusion speed of 4 mm/s. The microstructure, mechanical property, corrosion behavior and biocompatibility of the extruded Mg–Mn–Zn–Nd alloys have been investigated in this study. The microstructure was examined using X-ray diffraction analysis and optical microscopy. The mechanical properties were determined from uniaxial tensile and compressive tests. The corrosion behavior was investigated using electrochemical measurement. The biocompatibility was evaluated using osteoblast-like SaOS2 cells. The experimental results indicate that all extruded Mg–1Mn–2Zn–xNd alloys are composed of both α phase of Mg and a compound of Mg7Zn3 with very fine microstructures, and show good ductility and much higher mechanical strength than that of cast pure Mg and natural bone. The tensile strength and elongation of the extruded alloys increase with an increase in neodymium content. Their compressive strength does not change significantly with an increase in neodymium content. The extruded alloys show good biocompatibility and much higher corrosion resistance than that of cast pure Mg. The extruded Mg–1Mn–2Zn–1.0Nd alloy shows a great potential for biomedical applications due to the combination of enhanced mechanical properties, high corrosion resistance and good biocompatibility. - Highlights: • Extruded Mg–1Mn–2Zn–xNd alloys exhibit very fine microstructures. • Extrusion greatly improves the tensile property and corrosion behavior of alloys. • Tensile strength and ductility of the extruded alloys increase with Nd content. • Increase of Nd does not significantly alter the corrosion resistance. • Mg–1Mn–2Zn–1Nd alloy shows a great potential for biomedical applications

  1. Microstructures, mechanical and corrosion properties and biocompatibility of as extruded Mg–Mn–Zn–Nd alloys for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ying-Long, E-mail: ylzhou@fosu.edu.cn [Department of Mechatronics Engineering, Foshan University, Foshan 528000, Guangdong (China); Li, Yuncang [Institute for Frontier Materials, Deakin University, Victoria 3217 (Australia); Luo, Dong-Mei [Department of Civil Engineering, Foshan University, Foshan 528000, Guangdong (China); Ding, Yunfei; Hodgson, Peter [Institute for Frontier Materials, Deakin University, Victoria 3217 (Australia)

    2015-04-01

    Extruded Mg–1Mn–2Zn–xNd alloys (x = 0.5, 1.0, 1.5 mass %) have been developed for their potential use as biomaterials. The extrusion on the alloys was performed at temperature of 623 K with an extrusion ratio of 14.7 under an average extrusion speed of 4 mm/s. The microstructure, mechanical property, corrosion behavior and biocompatibility of the extruded Mg–Mn–Zn–Nd alloys have been investigated in this study. The microstructure was examined using X-ray diffraction analysis and optical microscopy. The mechanical properties were determined from uniaxial tensile and compressive tests. The corrosion behavior was investigated using electrochemical measurement. The biocompatibility was evaluated using osteoblast-like SaOS2 cells. The experimental results indicate that all extruded Mg–1Mn–2Zn–xNd alloys are composed of both α phase of Mg and a compound of Mg{sub 7}Zn{sub 3} with very fine microstructures, and show good ductility and much higher mechanical strength than that of cast pure Mg and natural bone. The tensile strength and elongation of the extruded alloys increase with an increase in neodymium content. Their compressive strength does not change significantly with an increase in neodymium content. The extruded alloys show good biocompatibility and much higher corrosion resistance than that of cast pure Mg. The extruded Mg–1Mn–2Zn–1.0Nd alloy shows a great potential for biomedical applications due to the combination of enhanced mechanical properties, high corrosion resistance and good biocompatibility. - Highlights: • Extruded Mg–1Mn–2Zn–xNd alloys exhibit very fine microstructures. • Extrusion greatly improves the tensile property and corrosion behavior of alloys. • Tensile strength and ductility of the extruded alloys increase with Nd content. • Increase of Nd does not significantly alter the corrosion resistance. • Mg–1Mn–2Zn–1Nd alloy shows a great potential for biomedical applications.

  2. Phytochemical Screening and Effect of Musa paradisiaca Stem Extrude on Rat Haematological Parameters

    Directory of Open Access Journals (Sweden)

    Paul C. Onyenekwe

    2013-01-01

    Full Text Available This study was carried out to investigate the phytochemical composition and effect of various concentrations of Musa paradisiaca stem extrude on haematological parameters in Albino Wistar rats. Twenty rats (62-121 g were randomly assigned into 5 groups of 4 rats each. Group 1 the control group, were given ordinary water while the test groups 2, 3, 4 and 5 were given 25, 50, 75 and 100% of the aqueous extract, respectively without water for 28 days. Rats were sacrificed and blood samples were collected by cardiac puncture then used for the haematological studies. Phytochemical tests were carried out using standard laboratory techniques. The results of the study show the presence of tannins and glycosides in abundance in the stem extrude while saponins, flavonoids, alkaloids, polyphenols and reducing sugars were present in moderate amounts but phlobatannins was absent. There was a significant (p>0.05 increase in rat RBC, PCV, Hb and WBC counts at concentrations of 75 and 100% when compared with the control and a significant (p>0.05 decrease in MCH and MCHC. The levels of MCV were not significantly altered at all extract concentrations. It can therefore be concluded thatMusa paradisiaca stem extrude has a haematopoietic and immunomodulatory effect consistent with its ethnomedicinal use.

  3. The effect of extrusion processing on the physiochemical properties of extruded orange pomace.

    Science.gov (United States)

    Huang, Ya-Ling; Ma, Ya-Sheng

    2016-02-01

    Soluble dietary fibre (SDF) is considered the most effective fraction of dietary fibre (DF) for human health. In this study, extrusion technology was applied to enhance the SDF obtained from orange pomace, a byproduct of juice extraction containing a high level of DF. The pomace was processed in a single-screw extruder at various barrel temperatures (X1; 115-135 °C), feed moistures (X2; 10-18 g/100g), and screw speeds (X3; 230-350 rpm). Based on response surface methodology, the optimum extrusion conditions, which produced a maximum SDF value of 30.36%, were as follows: barrel temperature, 129 °C; feed moisture, 15%; and screw speed, 299 rpm. Compared with unextruded pomace, SDF fraction in extrudate had a higher level of uronic acid. Furthermore, the extrusion process improved the physicochemical properties of extrudate, increasing the water-holding capacity, swelling, water solubility index, and cation-exchange capacity and decreasing the oil-holding capacity. PMID:26304360

  4. Starch-guar gum extrudates: microstructure, physicochemical properties and in-vitro digestion.

    Science.gov (United States)

    von Borries-Medrano, Erich; Jaime-Fonseca, Mónica R; Aguilar-Méndez, Miguel A

    2016-03-01

    Starch-guar gum mixtures were obtained by extrusion using a three-variable Box-Behnken statistic design. Morphology, expansion index, viscosity, crystallinity and digestion in vitro of the extruded samples were analyzed through response surface methodology (RSM). The extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the samples. Starch-guar gum samples showed expansion index and viscosity up to 1.55 and 1400mPas, respectively. The crystallinity of the samples was modified by adding guar gum to the extrudates, showing correlation between long-range order (X-ray diffraction) and short-range order (FTIR spectroscopy). Guar induced microstructural changes and its role in gelatinization-melting processes was significant. The rate of glucose release decreased from 0.47 to 0.43mM/min when the extrusion temperature decreased. However, adding guar gum to starch had no significant effect on glucose release. Overall, the extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the extruded samples. PMID:26471632

  5. Study on Hardware-in-loop Simulation of Twin-screw Extruder Experiment System

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>In order to facilitate the teaching of industrial processes and experiments on the twin-screw extruder control debugging,and be closer to the actual testing,to reduce the debugging costs and the risk of debugging process,the paper designs a hardware-in-loop simulation of twin-screw extruder experiment system which is closer to scene,low cost and high safety.The system through the establishment of twin-screw extruder’s mathematical model on computer to simulate the realistic system and there is hardware practicality in the computer simulation loop.The hardware based on C8051F020 can operate in the simulation loop in real time.In computer software design, we desigh man-machine interface that is intuitive and easy to operate,can reflect twin-screw extruder main operation information vividly.Finally,twin-screw extruder’s 3 heater temperature mathematical model and PID incremental control algorithm are presented.

  6. Microstructural transformation of quasicrystalline AlFeCrTi extruded bars upon long thermal treatments

    Energy Technology Data Exchange (ETDEWEB)

    García-Escorial, A., E-mail: age@cenim.csic.es [CENIM-CSIC, Avda. Gregorio del Amo, 8, 28040 Madrid (Spain); Natale, E.; Cremaschi, V.J. [Facultad de Ingeniería, Universidad de Buenos Aires, Paseo Colón 850, Buenos Aires (Argentina); Todd, I. [Dept. of Materials Science and Engineering Materials, University of Sheffield, Mappin St., Sheffield S1 3JD (United Kingdom); Lieblich, M. [CENIM-CSIC, Avda. Gregorio del Amo, 8, 28040 Madrid (Spain)

    2015-09-15

    Highlight: • Evolution upon heating of quasicrystalline AlFeCrTi alloy in bulk sample. • Warm extrusion of gas atomised powder particles. • Microstructural evolution of QC-AlFeCrTi extruded bars. - Abstract: Bulk Al{sub 93}Fe{sub 3}Cr{sub 2}Ti{sub 2} bars extruded from gas atomised powder particles present a microstructure of an aluminium matrix reinforced with a spherical nanoquasicrystalline phase. In this work the evolution of the microstructure of Al{sub 93}Fe{sub 3}Cr{sub 2}Ti{sub 2} extruded bars upon heating at 400 °C for up to 1000 h is investigated by means of X-ray diffraction, differential scanning calorimetry, scanning electron microscopy and transmission electron microscopy. According to our observations we propose that the quasicrystalline alloy evolves in two steps: a first step consists in the decomposition of the supersaturated solid solution of the matrix and the quasicrystals, and a second step in the transformation of the quasicrystals into the equilibrium phases.

  7. Effect of extruded wheat flour as a fat replacer on batter characteristics and cake quality.

    Science.gov (United States)

    Román, Laura; Santos, Isabel; Martínez, Mario M; Gómez, Manuel

    2015-12-01

    The effects of three levels of fat replacement (1/3, 2/3, and 3/3) by extruded flour paste and the effects of the presence of emulsifier on layer cake batter characteristics and final cake quality were studied. Replacement of oil by extruded flour paste modified the batter density and microscopy, reducing the number of air bubbles and increasing their size, while emulsifier incorporation facilitated air entrapment in batter. Emulsifier addition also increased the elastic and viscous moduli of the batter, while oil reduction resulted in a less structured batter. Emulsifier incorporation leads to good quality cakes, minimizing the negative effect of oil reduction, maintaining the volume and reducing the hardness of cakes. Furthermore, consumer acceptability of the reduced fat cakes was improved by the addition of emulsifier. Thus, the results confirmed the positive effect of partial oil substitution (up to 2/3) by extruded flour paste on the quality of reduced fat cakes when emulsifier was incorporated. PMID:26604393

  8. Starch-based extruded cereals enriched in fibers: a behavior of composite solid foams.

    Science.gov (United States)

    Chanvrier, Hélène; Desbois, Fabrice; Perotti, Fabienne; Salzmann, Claire; Chassagne, Sophie; Gumy, Jean-Claude; Blank, Imre

    2013-10-15

    Extruded cereals mainly composed of starch and enriched in fibers were produced with two types of base recipes: (i) one recipe mainly composed of wheat flour and (ii) one recipe mainly composed of corn and soya flours. The addition of fibers was performed through the use of oat bran concentrate or wheat bran, up to 32% of the recipe. The structure of the extrudates, assessed by X-ray tomography, pointed out the decrease of porosity and of mean cells size with the increase of the total dietary fibers content of the recipe. The hardness of the products, i.e. the maximum stress determined by a compression test, was linked to their porosity. The Gibson-Ashby relationship could be applied and the fit was even improved when considering the walls of the solid foam as composite materials. Fibers and proteins can be indeed considered as particles dispersed in the starchy phase. This work thus shows the impact of the structure of the extrudates on their mechanical properties. The structure is taken into account at different length scales; at the level of the porous structure and at the level of the phase of the main biopolymers present in the recipe (starch, proteins and fibers). The mechanical behavior of these products is then discussed according to their characteristics of composite solid foams. PMID:23987420

  9. Catalyst in Basic Oleochemicals

    Directory of Open Access Journals (Sweden)

    Eva Suyenty

    2007-10-01

    Full Text Available Currently Indonesia is the world largest palm oil producer with production volume reaching 16 million tones per annum. The high crude oil and ethylene prices in the last 3 – 4 years contribute to the healthy demand growth for basic oleochemicals: fatty acids and fatty alcohols. Oleochemicals are starting to replace crude oil derived products in various applications. As widely practiced in petrochemical industry, catalyst plays a very important role in the production of basic oleochemicals. Catalytic reactions are abound in the production of oleochemicals: Nickel based catalysts are used in the hydrogenation of unsaturated fatty acids; sodium methylate catalyst in the transesterification of triglycerides; sulfonic based polystyrene resin catalyst in esterification of fatty acids; and copper chromite/copper zinc catalyst in the high pressure hydrogenation of methyl esters or fatty acids to produce fatty alcohols. To maintain long catalyst life, it is crucial to ensure the absence of catalyst poisons and inhibitors in the feed. The preparation methods of nickel and copper chromite catalysts are as follows: precipitation, filtration, drying, and calcinations. Sodium methylate is derived from direct reaction of sodium metal and methanol under inert gas. The sulfonic based polystyrene resin is derived from sulfonation of polystyrene crosslinked with di-vinyl-benzene. © 2007 BCREC UNDIP. All rights reserved.[Presented at Symposium and Congress of MKICS 2007, 18-19 April 2007, Semarang, Indonesia][How to Cite: E. Suyenty, H. Sentosa, M. Agustine, S. Anwar, A. Lie, E. Sutanto. (2007. Catalyst in Basic Oleochemicals. Bulletin of Chemical Reaction Engineering and Catalysis, 2 (2-3: 22-31.  doi:10.9767/bcrec.2.2-3.6.22-31][How to Link/DOI: http://dx.doi.org/10.9767/bcrec.2.2-3.6.22-31 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/6

  10. Study of spent hydrorefining catalysts

    International Nuclear Information System (INIS)

    Aluminonickelmolybdenum catalysts for diesel fuel hydrorefining have been studied by DTA, XSPS, and diffuse reflection spectroscopy. Chemical and phase states of molybdenum compounds in samples of fresh catalyst, regenerated one after one year operation, and clogged with coke catalyst after five year operation, are determined. Chemical reactions and crystal-phase transformations of the molybdenum compounds during catalyst deactivation and regeneration are discussed

  11. Rumen fermentation and nutrient flow to the omasum in Holstein cows fed extruded canola seeds treated with or without lignosulfonate

    Directory of Open Access Journals (Sweden)

    Wallacy Barbacena Rosa dos Santos

    2012-07-01

    Full Text Available Four multiparous Holstein cows averaging 548 kg of body weight and 74 d in lactation were used in a Latin square design with four 21-d experimental periods to determine effects of feeding extruded versus non-extruded canola seed, with or without 50 g/kg lignosulfonate on rumen fermentation, nutrient flow to the omasum, and degradability of dry matter (DM and N of each diet. The DM effective degradability increased with extrusion and lignosulfonate treatment had no effect. The effective degradability of N was similar between diets. Lignosulfonate treatment of extruded versus non-extruded canola seeds decreased ruminal and total tract apparent digestibility of organic matter. The lowest apparent ruminal and highest intestinal digestibilities of protein, expressed as a percentage of N intake were observed for cows fed extruded canola seeds without lignosulfonate. Lignosulfonate treatment and extrusion had no effect on pH and concentrations of ammonia N and volatile fatty acids in the rumen. Results suggest that extruded canola seed untreated with formaldehyde may stimulate efficiency of microbial protein synthesis and is an effective means of increasing the availability of protein in the small intestine without affecting the total tract apparent digestibility of protein.

  12. Open segmental fracture of both bone forearm and dislocation of ipsilateral elbow with extruded middle segment radius

    Directory of Open Access Journals (Sweden)

    Pawan Kumar

    2013-01-01

    Full Text Available Extruded middle segment of radius with open segmental fracture both bone forearm and dislocation of ipsilateral elbow is a rare injury. A 12-year-old child presented to us within 4 hours following fall from tree. The child′s mother was carrying a 12-cm-long extruded soiled segment of radius. The extruded bone was thoroughly washed. The medullary cavity was properly syringed with antiseptic solution. The bone was autoclaved and put in the muscle plane of the distal forearm after debridement of the wound. After 5 days, a 2.5-mm K-wire was introduced by retrograde method into the proximal radius by passing through the extruded segment. Another 2.5-mm K-wire was passed in ulna. The limb was evaluated clinicoradiologically every 2 weeks. The wound was healed by primary intention. At 4 months, the reposed bone appeared less dense radiologically and K-wire seemed to be out of the bone. In the subsequent months, the roentgenograms show remodeling of the extruded fragment. After 20 weeks, the K-wires were removed (first ulnar and then radial. Complete union was achieved with full range of movement except loss of few degrees of extension of elbow and thumb. This case is reported to show a good outcome following successful incorporation of an extruded segment of radius in an open fracture.

  13. Efeito do envelhecimento de catalisadores Ziegler-Natta à base de neodímio sobre a polimerização de 2-metil, 1,3-butadieno Effect of aging time of Ziegler-Natta catalysts based on neodimium for 2-methyl, 1,3-butadiene polymerization

    Directory of Open Access Journals (Sweden)

    André Luiz Carneiro Simões

    2013-01-01

    Full Text Available O objetivo deste trabalho foi estudar o efeito do tempo de envelhecimento natural do sistema catalítico versatato de neodímio/hidreto de di-isobutilalumínio/cloreto de t-butila sobre a polimerização de 2-metil, 1,3-butadieno (isopreno. Foram avaliadas a atividade catalítica e conversão, além da massa molar, distribuição de massa molar e microestrutura dos polímeros. Foi objetivo estudar também as características micro e macroestruturais do poli-1,4-cis-isopreno ao longo da polimerização. Os catalisadores envelhecidos apresentaram tempos mais curtos ao longo da polimerização e uma conversão mais alta em relação ao catalisador não envelhecido. Estes resultados em conjunto com a menor atividade catalítica nos catalisadores envelhecidos sugerem a provável desativação de alguns sítios ativos mais sensíveis. Não foi observada influência do envelhecimento do catalisador sobre a microestrutura do polímero. Houve também aumento da massa molar e estreitamento na polidispersão conforme o aumento da conversão.The goal of this work was to study the aging effects of the catalytic system neodymium versatate/diisobutylaluminium hydride/t-butyl chloride on 2-methyl, 1.3-butadiene (isoprene polymerization. The catalytic activity, conversion and polymer characteristics (molar mass, molar mass distribution and microstructure were evaluated. The macro and microstructural characteristics of poly-1.4-cis-isoprene along the polymerization were also studied. The aged catalysts have shorter times along the polymerization and a higher conversion than the non-aged catalyst. Together with the lower catalytic activity for aged catalysts, these results point to possible disabling of the most sensitive active sites. Aging of the catalyst did not affect the polymer microstructure. As the conversion progressed, the molar mass increased with a narrowing in the molecular weight distribution.

  14. Raw, extruded and expanded pea (Pisum sativum in dairy cows diets

    Directory of Open Access Journals (Sweden)

    Gianfranco Piva

    2010-01-01

    Full Text Available The objective of the study was to evaluate the nutritive value of raw, extruded or expanded peas relative to soybean meal in lactating dairy cows feeding. Twenty four Italian Holstein cows (8 primiparous and 16 pluriparous, 604 ± 109 kg body weight, 34.5 ± 2.5 kg/d milk yield, were randomly assigned to four dietary treatments in a 4x4 Latin square arrangement with periods of four weeks and washout period of seven days. Diets were fed ad libitum(5% orts. The bulk of the base diet on a dry matter basis was corn silage (31.2%, alfalfa hay (16.7%, grass hay (4.1%, protein supplement (10.3%, whole cotton seed (8.5%, corn and barley mix (24.9%, soybean meal (3.4% and calcium soap (0.9%. The pea (2.5 kg/cow/day partially replaced the soybean meal and totally replaced the barley meal of the base diet. The unprocessed or differently processed pea did not affect the dry matter intake. The extruded pea group had a 3.2% increase (P< 0.05 of the milk yield compared to the control group. When estimated as contrast analysis, the technological treatment (extruded or expanded on peas did not modify the milk yield and composition. Among pea diets, animal fed the extruded pea had the higher (P< 0.05 milk protein content, although not different than that of the control group. The rumen acetate was reduced (P< 0.05 and the butyrate and valerate were increased (P< 0.05 in animals fed extruded pea compared to the control. No differences were observed among feeding groups on blood parameters except for the cholesterol level higher (P< 0.05 in animals fed the expanded pea diet. There were no effects of diets on milk rennet coagulation characteris- tics. Results support the partial substitution of soybean meal and the total substitution of barley meal with peas in diets for lactating cows with no negative effects on milk yield and composition.

  15. Catalyst for microelectromechanical systems microreactors

    Energy Technology Data Exchange (ETDEWEB)

    Morse, Jeffrey D. (Martinez, CA); Sopchak, David A. (Livermore, CA); Upadhye, Ravindra S. (Pleasanton, CA); Reynolds, John G. (San Ramon, CA); Satcher, Joseph H. (Patterson, CA); Gash, Alex E. (Brentwood, CA)

    2011-11-15

    A microreactor comprising a silicon wafer, a multiplicity of microchannels in the silicon wafer, and a catalyst coating the microchannels. In one embodiment the catalyst coating the microchannels comprises a nanostructured material. In another embodiment the catalyst coating the microchannels comprises an aerogel. In another embodiment the catalyst coating the microchannels comprises a solgel. In another embodiment the catalyst coating the microchannels comprises carbon nanotubes.

  16. Catalyst for microelectromechanical systems microreactors

    Science.gov (United States)

    Morse, Jeffrey D.; Sopchak, David A.; Upadhye, Ravindra S.; Reynolds, John G.; Satcher, Joseph H.; Gash, Alex E.

    2010-06-29

    A microreactor comprising a silicon wafer, a multiplicity of microchannels in the silicon wafer, and a catalyst coating the microchannels. In one embodiment the catalyst coating the microchannels comprises a nanostructured material. In another embodiment the catalyst coating the microchannels comprises an aerogel. In another embodiment the catalyst coating the microchannels comprises a solgel. In another embodiment the catalyst coating the microchannels comprises carbon nanotubes.

  17. Characterization of three-way automotive catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Kenik, E.A.; More, K.L. [Oak Ridge National Lab., TN (United States); LaBarge, W. [Delphi Automotive Systems, Flint, MI (United States)] [and others

    1997-04-01

    The CRADA between Delphi Automotive Systems (Delphi; formerly General Motors - AC Delco, Systems) and Lockheed Martin Energy Research (LMER) on automotive catalysts was completed at the end of FY96, after a ten month, no-cost extension. The CRADA was aimed at improved performance and lifetime of noble metal based three-way-catalysts (TWC), which are the primary catalytic system for automotive emission control systems. While these TWC can meet the currently required emission standards, higher than optimum noble metal loadings are often required to meet lifetime requirements. In addition, more stringent emission standards will be imposed in the near future, demanding improved performance and service life from these catalysts. Understanding the changes of TWC conversion efficiency with ageing is a critical need in improving these catalysts. Initially in a fresh catalyst, the active material is often distributed on a very fine scale, approaching single atoms or small atomic clusters. As such, a wide range of analytical techniques have been employed to provide high spatial resolution characterization of the evolving state of the catalytic material.

  18. Mesoporous molecular sieve catalysts

    DEFF Research Database (Denmark)

    Højholt, Karen Thrane

    the micropores. Furthermore, preliminary work was done using mesoporous ZSM-5 zeolites as support material for anchoring molecular CoMo6 species for the application as potential bi-functional catalyst in simultaneous hydrodesulfurisation (HDS) and hydrocracking. HDS activity tests revealed that the...... of different catalytic applications. Primarily the zeolites were modified regarding the porosity and the introduction of metals to the framework. The obtained materials were used as solid acid catalysts, as an inert matrix for stabilising metal nanoparticles and as an anchoring material for molecular...... only be used as solid acid catalysts but can also be used as a size-selective matrix. It was shown that it is possible to encapsulate 1-2 nm sized gold nanoparticles by silicalite-1 or ZSM-5 zeolite crystals thereby forming a sintering-stable and substrate size-selective oxidation catalyst. After...

  19. Epoxidation catalyst and process

    Science.gov (United States)

    Linic, Suljo; Christopher, Phillip

    2010-10-26

    Disclosed herein is a catalytic method of converting alkenes to epoxides. This method generally includes reacting alkenes with oxygen in the presence of a specific silver catalyst under conditions suitable to produce a yield of the epoxides. The specific silver catalyst is a silver nanocrystal having a plurality of surface planes, a substantial portion of which is defined by Miller indices of (100). The reaction is performed by charging a suitable reactor with this silver catalyst and then feeding the reactants to the reactor under conditions to carry out the reaction. The reaction may be performed in batch, or as a continuous process that employs a recycle of any unreacted alkenes. The specific silver catalyst has unexpectedly high selectivity for epoxide products. Consequently, this general method (and its various embodiments) will result in extraordinarily high epoxide yields heretofore unattainable.

  20. Heterogeneous chromium catalysts

    OpenAIRE

    2005-01-01

    The present invention relates to a heterogeneous chromium catalyst system for the polymerisation of ethylene and/or alpha olefins prepared by the steps of: (a) providing a silica-containing support, (b) treating the silica-containing support with a chromium compound to form a chromium-based silica-containing support, (c) activating the chromium-based silica-containing support, (d) chemically reducing the activated chromium-based silica-containing support to produce a precursor catalyst, (e) r...

  1. Aftermarket catalyst durability evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bruetsch, R.I.; Cheng, J.P.; Hellman, K.H.

    1986-01-01

    Suppliers have introduced replacement aftermarket catalytic converters which are characterized by design differences from the original equipment converters in the direction of lower costs. The objective of the work reported here was to test a group of nine aftermarket catalysts from three manufacturers for 25,000 miles. Mileage was accumulated on three routes in Maryland and West Virginia characterized by varying degrees of tire wear. All catalysts were dynamometer tested on the same vehicle at the same laboratory.

  2. Synthesis and characterization of Fe–Ni/ɣ-Al2O3 egg-shell catalyst for H2 generation by ammonia decomposition

    DEFF Research Database (Denmark)

    Silva, Hugo José Lopes; Nielsen, Morten Godtfred; Fiordaliso, Elisabetta Maria;

    2015-01-01

    the active phase should match with the type of reaction. In this work, a novel synthesis route was developed for the preparation of a Fe–Ni/ɣ-Al2O3 egg-shell catalyst. Egg-shell is a preferred profile considering the highly endothermic nature of ammonia decomposition reaction. The high viscosity of......The Fe–Ni alloyed nanoparticles are a promising alternative to expensive ruthenium-based catalysts for a real-scale application of hydrogen generation by ammonia decomposition. In practical applications, millimeter-sized extrudates are used as catalyst supports, where the spatial distribution of....... The outer-shell region showed the presence of Fe and Ni alloyed nanoparticles with a size of approximately 5nm.. The egg-shell catalyst showed significant higher activity in ammonia decomposition by converting 3 times more ammonia to equilibrium conversion than either egg-white or catalyst with...

  3. Characterization and regeneration of Pt-catalysts deactivated in municipal waste flue gas

    International Nuclear Information System (INIS)

    Severe deactivation was observed for industrially aged catalysts used in waste incineration plants and tested in lab-scale. Possible compounds that cause deactivation of these Pt-based CO oxidation catalysts have been studied. Kinetic observations of industrial and model catalysts showed that siloxanes were the most severe catalyst poisons, although acidic sulfur compounds also caused deactivation. Furthermore, a method for on-site regeneration without shutdown of the catalytic flue gas cleaning system has been developed, i.e. an addition of H2/N2 gas to the off-gas can completely restore the activity of the deactivated catalysts. (author)

  4. Impact of extruded flaxseed meal supplemented diet on growth performance, oxidative stability and quality of broiler meat and meat products

    Directory of Open Access Journals (Sweden)

    Anjum Faqir Muhammad

    2013-02-01

    Full Text Available Abstract This study was intended to explore the effect of extruded flaxseed meal supplemented diet on broiler growth performance, oxidative stability and organoleptic characteristics of broiler meat and meat products. 120 (day old broiler chicks were randomly allotted to 12 experimental groups and fed on diets containing extruded flaxseed meal at 0, 5, 10 and 15%. The supplementation of extruded flaxseed in the diet decreases the body weight gain, feed intake and increased feed conversion ratio (FCR values of broilers. The antioxidant enzymes were strongly influenced by different levels of extruded flaxseed supplementation among treatments. The TBARS assay revealed that maximum malondialdehyde were produced in T3 containing highest extruded flaxseed level (15% and minimum malondialdehyde were produced in T0 treatment having no extruded flaxseed. The TBARS values ranged from 0.850-2.106 and 0.460-1.052 in leg and breast met respectively. The Free radical scavenging activity varied significantly and DPPH values of breast meat ranged from 20.70% to 39.09% and in leg meat 23.53% to 43.09% respectively. The sensory acceptability of broiler meat nuggets was decreased with the increase in the level of flaxseeds due to the lipid peroxidation of polyunsaturated fatty acids (PUFA which generated off flavors and bad odors. Feeding extruded flaxseed to chicken through feed strongly inflated the quality and functional properties, fatty acid contents and reduced the oxidative stability of broiler meat and meat products. The present study concludes that up to 10% of flaxseed meal may be used in broiler diet to enhance the omega 3 fatty acids content in the broiler meat.

  5. Magnetic and dendritic catalysts.

    Science.gov (United States)

    Wang, Dong; Deraedt, Christophe; Ruiz, Jaime; Astruc, Didier

    2015-07-21

    The recovery and reuse of catalysts is a major challenge in the development of sustainable chemical processes. Two methods at the frontier between homogeneous and heterogeneous catalysis have recently emerged for addressing this problem: loading the catalyst onto a dendrimer or onto a magnetic nanoparticle. In this Account, we describe representative examples of these two methods, primarily from our research group, and compare them. We then describe new chemistry that combines the benefits of these two methods of catalysis. Classic dendritic catalysis has involved either attaching the catalyst covalently at the branch termini or within the dendrimer core. We have used chelating pyridyltriazole ligands to insolubilize catalysts at the termini of dendrimers, providing an efficient, recyclable heterogeneous catalysts. With the addition of dendritic unimolecular micelles olefin metathesis reactions catalyzed by commercial Grubbs-type ruthenium-benzylidene complexes in water required unusually low amounts of catalyst. When such dendritic micelles include intradendritic ligands, both the micellar effect and ligand acceleration promote faster catalysis in water. With these types of catalysts, we could carry out azide alkyne cycloaddition ("click") chemistry with only ppm amounts of CuSO4·5H2O and sodium ascorbate under ambient conditions. Alternatively we can attach catalysts to the surface of superparamagnetic iron oxide nanoparticles (SPIONs), essentially magnetite (Fe3O4) or maghemite (γ-Fe2O3), offering the opportunity to recover the catalysts using magnets. Taking advantage of the merits of both of these strategies, we and others have developed a new generation of recyclable catalysts: dendritic magnetically recoverable catalysts. In particular, some of our catalysts with a γ-Fe2O3@SiO2 core and 1,2,3-triazole tethers and loaded with Pd nanoparticles generate strong positive dendritic effects with respect to ligand loading, catalyst loading, catalytic activity and

  6. Effect of dynamic strain aging on the appearance of the rare earth texture component in magnesium alloys

    International Nuclear Information System (INIS)

    Highlights: → High intensity of the RE texture component gave distinct mechanical properties. → DSA took place during compression over a broad range. → Extruding under DSA regions enhanced the formation of the RE texture components. - Abstract: Binary Mg alloys were prepared containing Zn, Ce and Gd. These were extruded and the resulting mechanical properties were determined. The intensities of the rare earth (RE) texture components were measured and linked to the extrusion conditions. Tension and compression testing was carried out on samples taken from extruded bars and a Mg-0.5Ce cast alloy. Over particular temperature and strain rate ranges, dynamic strain aging (DSA) was observed. The ranges over which DSA occurred during testing are compared with the conditions under which the RE texture components were produced during extrusion. It is concluded that formation of the RE texture components can be enhanced by extruding when the rate sensitivity is negative, i.e. under conditions where DSA is taking place.

  7. Catalyst component interactions in nickel/alumina catalyst

    Directory of Open Access Journals (Sweden)

    Kiš Erne E.

    2007-01-01

    Full Text Available The influence of nickel loading (5; 10; 20 wt% Ni, temperature of heat treatment (400; 700; 1100°C and way of catalyst preparation on the catalyst component interactions (CCI in the impregnated, mechanical powder mixed and co-precipitated catalyst was investigated. For sample characterization, low temperature nitrogen adsorption (LTNA and X-ray diffraction (XRD were applied. Significant differences were revealed, concerning CCI in dependence of nickel loading, temperature of heat treatment and way of catalyst preparation. The obtained results show that the support metal oxide interactions (SMI in impregnated and co-precipitated catalysts are more intensive than in the mechanical powder mixed catalyst. The degree and intensity of CCI is expressed by the ratio of real and theoretical surface area of the catalyst. This ratio can be used for a quantitative estimation of CCI and it is generally applicable to all types of heterogeneous catalysts.

  8. Enhancing anaerobic digestion of high-pressure extruded food waste by inoculum optimization.

    Science.gov (United States)

    Kong, Xin; Xu, Shuang; Liu, Jianguo; Li, Huan; Zhao, Ke; He, Liang

    2016-01-15

    The inoculation for extruded food waste anaerobic digestion (AD) was optimized to improve methane (CH4) yield. The inoculum of acclimated anaerobic sludge resulted in high biodegradability, producing CH4 yields from 580 mLCH4 g(-1)·VSadded to 605 mLCH4 g(-1)·VSadded, with corresponding BDCH4 ranging from 90% to 94%. We also investigated inoculum to substrate ratios (ISRs). With regards to digested slurry as inoculum, we found that a decrease in ISR improved CH4 yield, while a lower ISR prolonged the lag time of the initial AD stage due to lipid inhibition caused by excessive food waste. These results demonstrate that minimal inocula are required to start the AD system for high-pressure extruded food waste because it is easily biodegraded. High ammonia concentration had a negative effect on CH4 production (i.e., when free ammonia nitrogen [FAN] increased from 20 to 30 mg L(-1) to 120-140 mg L(-1), the CH4 yield decreased by 25%), suggesting that FAN was a significant inhibitor in CH4 yield reduction. In terms of CH4 yield and lag time of the AD process, the optimal inoculation of digested slurry for the extruded food waste had an ISR of 0.33 with CH4 yield of 505 mLCH4 g(-1)VSadded, which was 20% higher than what was found for higher ISR controls of 2, 1 and 0.5. PMID:26468605

  9. The effect of extrusion on the functional components and in vitro lycopene bioaccessibility of tomato pulp added corn extrudates.

    Science.gov (United States)

    Tonyali, Bade; Sensoy, Ilkay; Karakaya, Sibel

    2016-02-01

    The effect of processing on functional ingredients and their in vitro bioaccessibility should be investigated to develop better food products. Tomato pulp was added as a functional ingredient to extrudates. The effects of extrusion on the functional properties of the extrudates and the in vitro bioaccessibility of lycopene were investigated. Two different temperature sets were applied during extrusion: 80 °C, 90 °C, 100 °C and 130 °C and 80 °C, 100 °C, 130 °C and 160 °C. Screw speed and feed rate were kept constant at 225 rpm and 36 ± 1 g min(-1), respectively. The feed moisture content was adjusted to 30 ± 1% by mixing the tomato pulp to the corn grit. Antioxidant activity and the total phenolic content decreased after the extrusion process. High performance liquid chromatography (HPLC) analysis indicated that the lycopene content decreased after the extrusion process when feed and extrudates were compared. In vitro bioaccessibility of lycopene for the extruded samples with 160 °C last zone treatment temperature was higher than the feed and extruded samples with 130 °C last zone treatment temperature. The results indicate that extrusion affects the food matrix and the release of functional components. PMID:26674172

  10. Effect of incorporation of corn byproducts on quality of baked and extruded products from wheat flour and semolina.

    Science.gov (United States)

    Sharma, Savita; Gupta, Jatinder Pal; Nagi, H P S; Kumar, Rakesh

    2012-10-01

    The effect of blending level (0, 5, 10, 15 and 20%) of corn bran, defatted germ and gluten with wheat flour on the physico-chemical properties (protein, crude fiber, phosphorus, iron and calcium), baking properties of bread, muffins and cookies, and extrusion properties of noodles and extruded snacks prepared from semolina were examined. Blending of wheat flour and corn byproducts significantly increased the protein, crude fiber, phosphorus, iron and calcium contents. Breads from gluten blends had higher loaf volume as compared to bran and germ breads. Among corn byproducts, gluten cookies were rated superior with respect to top grain. Muffins from germ blends and gluten blends had higher acceptability scores than the bran muffins. Blending of corn bran, defatted germ and gluten at 5 and 10% with wheat flour resulted in satisfactory bread, cookie, and muffin score. Quality of noodles was significantly influenced by addition of corn byproducts and their levels. Corn byproducts blending had significant influence on cooking time, however, gruel solid loss affected non-significantly in case of noodles. Expansion ratio and density of extruded snacks was affected non significantly by blending source and blending level. However, significant effect was observed on amperage, pressure, yield and overall acceptability of extruded snacks. Acceptable extruded products (noodles and extruded snacks) could be produced by blending corn byproducts with semolina upto 10% level. PMID:24082269

  11. Physicochemical Changes and Resistant-Starch Content of Extruded Cornstarch with and without Storage at Refrigerator Temperatures

    Directory of Open Access Journals (Sweden)

    David Neder-Suárez

    2016-08-01

    Full Text Available Effects of extrusion cooking and low-temperature storage on the physicochemical changes and resistant starch (RS content in cornstarch were evaluated. The cornstarch was conditioned at 20%–40% moisture contents and extruded in the range 90–130 °C and at screw speeds in the range 200–360 rpm. The extrudates were stored at 4 °C for 120 h and then at room temperature. The water absorption, solubility index, RS content, viscoelastic, thermal, and microstructural properties of the extrudates were evaluated before and after storage. The extrusion temperature and moisture content significantly affected the physicochemical properties of the extrudates before and after storage. The RS content increased with increasing moisture content and extrusion temperature, and the viscoelastic and thermal properties showed related behaviors. Microscopic analysis showed that extrusion cooking damaged the native starch structure, producing gelatinization and retrogradation and forming RS. The starch containing 35% moisture and extruded at 120 °C and 320 rpm produced the most RS (1.13 g/100 g after to storage at low temperature. Although the RS formation was low, the results suggest that extrusion cooking could be advantageous for RS production and application in the food industry since it is a pollution less, continuous process requiring only a short residence time.

  12. Effect of extrusion processing parameters on microstructure and mechanical properties of as-extruded AZ31 sheets

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The AZ31 sheets were prepared by extrusion. The effects of the extrusion processing parameters including the temperature,extrusion ratio, and structure of the extrusion die on the microstructure and mechanical properties of the as-extruded AZ31 sheets were investigated. The results show that the partial grains grow abnormally.and the mechanical and anisotropic properties of the as-extruded AZ31 sheets have little change at the extrusion temperatures of 380-400 ℃ and the extrusion ratio of 13.3. With the increase of the extrusion ratio, the microstructure of the as-extruded AZ31 sheets by conventional die becomes finer and more uniform, and the elongation rate increases, but the strength decreases and its anisotropy becomes worse. Under the porthole die, finer and more uniform microstructure, higher mechanical properties and better anisotropy can be brought for the as-extruded AZ31 sheets.The extruded AZ31 sheets by the porthole die have better anneal process of 300℃ and 1 h.

  13. MR imaging findings of a sequestered disc in the lumbar spine: a comparison with an extruded disc

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Su Youn; Park, Ji Seon; Ryu, Kyung Nam [Kyung Hee University Medical Center, Seoul (Korea, Republic of); Jin, Wook [Kyung Hee University East-west Neo Medical Center, Seoul (Korea, Republic of)

    2007-10-15

    To compare the MR findings of a sequestered disc with an extruded disc. MR images of 28 patients with a sequestered disc and 18 patients with an extruded disc were retrospectively reviewed. Patients with sequestered discs were divided into two groups whether definite separation from the parent disc was or was not seen. In the latter group (definite separation not seen) and the extruded disc group of patients, the signal intensities of the herniated discs were compared with the signal intensities of the parent discs and were evaluated on T1-and T2-weighted images. We also assessed the presence of a notch within the herniated disc. In the sequestered disc group of patients (28 discs), only 5 discs (18%) showed obvious separation from the parent disc. Among the remaining 23 discs with indefinite separation, the notch was visible in 14 discs (61%) and 9 discs (39%) had no notch. In the extruded disc group (18 discs), the notch was visible in 2 (11%) discs and the difference between the two groups was statistically significant ({rho} 0.0002). The signal intensities of the herniated discs on T1-weighted images were isointense in both the sequestered and extruded discs. The difference of incidence of high signal intensities on T2-weighted images was not statistically significant ({rho} = 0.125). It is necessary to consider the possibility of the presence of a sequestered disc when a herniated disc material shows a notch.

  14. Gastrointestinal transit of extruded or pelletized diets in pacu fed distinct inclusion levels of lipid and carbohydrate

    Directory of Open Access Journals (Sweden)

    Claucia Aparecida Honorato

    2014-11-01

    Full Text Available The objective of this work was to evaluate the effect of pelletized or extruded diets, with different levels of carbohydrate and lipid, on the gastrointestinal transit time (GITT and its modulation in pacu (Piaractus mesopotamicus. One hundred and eighty pacu juveniles were fed with eight isonitrogenous diets containing two carbohydrate levels (40 and 50% and two lipid levels (4 and 8%. Four diets were pelletized and four were extruded. Carbohydrate and lipid experimental levels caused no changes to the bolus transit time. However, the bolus permanence time was related to diet processing. Fish fed pelletized diets exhibited the highest gastrointestinal transit time. Regression analysis of bolus behavior for pelletized and extruded diets with 4% lipid depicted different fits. GITT regression analysis of fish fed 8% lipid was fitted to a cubic equation and displayed adjustments of food permanence, with enhanced utilization of the diets, either with extruded or pelletized diets. GITT of fish fed extruded diets with 4% lipid was adjusted to a linear equation. The GITT of pacu depends on the diet processing and is affected by dietary levels of lipid and carbohydrate.

  15. SELECTED PHYSICAL PROPERTIES OF EXTRUDED COMPOSITES TYPE OF POROUS PVC-METAL

    Directory of Open Access Journals (Sweden)

    Aneta Tor-Świątek

    2014-09-01

    Full Text Available The article presents studies of selected physical and mechanical properties of hybrid materials type of polymer-metal. In the frame of this work modification of PVC with the iron and copper powder in amount of 0, 1.5 and 3% and blowing agent in amount of 0, 0.5, 1% was done. Extrudates in a form of pipe were tested to determine density, porosity, maximum tensile stress, stress at break, modulus of elasticity and elongation with break. The samples were also observed in a microscope. The studies have shown significant influence of the added components on the properties tested.

  16. Highly CO2 sensitive extruded fluorescent plastic indicator film based on HPTS

    OpenAIRE

    Mills, Andrew; Yusufu, Dilidaer

    2015-01-01

    Highly-sensitive optical fluorescent extruded plastic films are reported for the detection of gaseous and dissolved CO2. The pH-sensitive fluorescent dye used is 8-Hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS, PTS-) coated on the surface of hydrophilic fumed silica and the base is tetrabutylammonium hydroxide (TBAH). The above components are used to create an HPTS pigment (i.e. HPTS/SiO2/TBAH) with a high CO2 sensitivity (%CO2(S=1/2) = 0.16%) and fast 50% response (t50↓) = 2 s an...

  17. Gluten-Free Bread Production by the Corn Meal and Soybean Flour Extruded Blend Usage

    OpenAIRE

    Duška Ćurić; Dubravka Novotni; Dubravka Tušak; Ingrid Bauman; Domagoj Gabrić

    2007-01-01

    The most common disease caused by cereal protein ingestion is celiac disease. This can be treated only by a diet that excludes all foods containing wheat, barley, rye and oat proteins. Corn meal (CM) and defatted soybean fl our (DSF) blend processed by High Temperature Short Time (HTST) extrusion cooking for gluten-free bread production was investigated. Corn meal and soybean fl our were extruded in three different proportions (w/w): 100 CM / 0 DSF; 87.5 CM / 12.5 DSF; 75 CM / 25 DS. After mi...

  18. Surface quality of extruding metal special-shape products and frictional behavior in optimized die cavity

    Institute of Scientific and Technical Information of China (English)

    QI Hong-yuan; ZHU Heng-jun

    2004-01-01

    With the help of Complex Function Mapping theory, the complicated three-dimensional deformation problems are transferred into two-dimensional problems, and the function of strain ratio field is analyzed in the metal plastic extruding deformation. Taking the strain-hardening effect of metal deformation into account, the relationship between friction behavior and optimized mathematical model is analyzed by the numerical analysis friction energy dissipation function. As a result, the method of lowering the material hardening and decreasing the reduction ratio over multi-procedures can be used to improve the surface quality of metal special-shape extrusion products.

  19. Indomethacin-Kollidon VA64 Extrudates: A Mechanistic Study of pH-Dependent Controlled Release.

    Science.gov (United States)

    Tres, Francesco; Treacher, Kevin; Booth, Jonathan; Hughes, Leslie P; Wren, Stephen A C; Aylott, Jonathan W; Burley, Jonathan C

    2016-03-01

    Because of its weakly acidic nature (pKa of 4.5), indomethacin presents an aqueous solubility that significantly increases when changing from acidic to neutral/alkaline pH (1.5 μg/mL at pH 1.2 and 105.2 μg/mL at pH 7.4). We have therefore investigated the impact of the dissolution medium pH on the dissolution performance of indomethacin:Kollidon VA64 extrudates. The impact of the drug loading on the dissolution properties of these systems was also examined (5%, 15%, 30%, 50%, 70%, and 90% drug loading). Time-resolved Raman spectroscopy along with in-line UV-vis spectrophotometry was employed to directly relate changes in dissolution behavior to physicochemical changes that occur to the extrudate during the test. The dissolution tests were performed in pH 2 HCl (to mimic the stomach conditions), and this was then switched during the experiment to pH 6.8 phosphate buffer (to simulate the poststomach conditions). The rotating disc dissolution rate test was also used to simultaneously measure the dissolution rate of both the drug and the polymer. We found that in pH 2 HCl buffer, for the 15% or higher drug-loaded extrudates, Kollidon VA64 preferentially dissolves from the exterior of the compact leaving an amorphous drug-rich hydrophobic shell, which, similarly to an enteric coating, inhibits the drug release. The in situ formation of an enteric coating has been previously hypothesized, and this has been the first time that is directly observed in a pH-variable dissolution test. The dissolution medium switch to pH 6.8 phosphate buffer, due to the large increase of the aqueous solubility of indomethacin at this pH, leads to rapid dissolution of the material forming the coating and therefore total drug release. In contrast, the 5% extrudate is fully hydrated and quickly dissolves at low pH pointing to a dissolution performance dependent on highly water-soluble Kollidon VA64. PMID:26845251

  20. Low-cost apparatus for measuring undispersed particles in extruded plastic ribbon

    International Nuclear Information System (INIS)

    An apparatus was designed and constructed that quantitatively measures the number and size of poorly dispersed particles ( >3 μm diameter) that protrude above the surface of an extruded plastic ribbon (0.10-0.15 mm thick). Major components of the apparatus include a set of in-house fabricated dispensing and take-up wheels for guiding the ribbon's path, a commercially available variable differential transducer, and custom-designed software based on National Instruments' LABVIEW platform. The reproducibility and repeatability of the technique are presented, along with data comparing this approach to more conventional, albeit labor-intensive manual approaches

  1. Plastification of polymers in twin-screw-extruders: New visualization technic using high-speed imaging

    International Nuclear Information System (INIS)

    The initial melting of the first granules through plastic energy dissipation (PED) at the beginning of the melting zone, in the co-rotating twin-screw extruder is visualized in this work. The visualization was created through the use of a high speed camera in the cross section of the melting zone. The parameters screw speed, granule-temperature, temperature-profile, type of polymer and back pressure were examined. It was shown that the screw speed and the temperature-profile have significant influence on the rate of initial melting

  2. Plastification of polymers in twin-screw-extruders: New visualization technic using high-speed imaging

    Energy Technology Data Exchange (ETDEWEB)

    Knieper, A., E-mail: Alexander.Knieper@lbf.fraunhofer.de, E-mail: Christian.Beinert@lbf.fraunhofer.de; Beinert, C., E-mail: Alexander.Knieper@lbf.fraunhofer.de, E-mail: Christian.Beinert@lbf.fraunhofer.de [Group Polymer Processing, Division Plastics, Fraunhofer-Institute LBF (Germany)

    2014-05-15

    The initial melting of the first granules through plastic energy dissipation (PED) at the beginning of the melting zone, in the co-rotating twin-screw extruder is visualized in this work. The visualization was created through the use of a high speed camera in the cross section of the melting zone. The parameters screw speed, granule-temperature, temperature-profile, type of polymer and back pressure were examined. It was shown that the screw speed and the temperature-profile have significant influence on the rate of initial melting.

  3. Strain-hardening and warm deformation behaviors of extruded Mg–Sn–Yb alloy sheet

    OpenAIRE

    Jing Jiang; Guangli Bi; Guoyong Wang; Qing Jiang; Jianshe Lian; Zhonghao Jiang

    2014-01-01

    Strain-hardening and warm deformation behaviors of extruded Mg–2Sn–0.5Yb alloy (at.%) sheet were investigated in uniaxial tensile test at temperatures of 25–250 °C and strain rates of 1 × 10−3 s−1–0.1 s−1. The data fit with the Kocks–Mecking type plots were used to show different stages of strain hardening. Besides III-stage and IV-stage, the absence of the II-stage strain hardening at room temperature should be related to the sufficient dynamic recrystallization during extrusion. The decreas...

  4. Rheology of Steel Fibre Containing Alumina-Magnesia-Extruded Graphite Pellets Self-Flowing Castables

    Institute of Scientific and Technical Information of China (English)

    K.Balamurugan; K.Sankaranarayanane; ZHOU Xianxin; Michel Riguad

    2007-01-01

    The influences of adding steel fibres of different lengths up to 3 volume percentages,on the rheological behaviour of an alumina-magnesia-extruded graphite pellet containing castables have been studied using a rheometer.Free-flow measurements have shown that the flow is severely affected by increasing the length of steel fibres.The calculated values of rheological constants indicate that 19 mm and 25 mm fibre up to 2 volume percentage is permitted while one volume percentage of 50 mm fibres severely degrades the rheology of the castable.

  5. Analysis of the cyclic behavior and fatigue damage of extruded AA2017 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    May, A., E-mail: abdelghani1980@yahoo.fr [INSA/GPM, CNRS UMR 6634, BP 08 avenue de l' université, 76801 Saint Etienne du Rouvray Cedex (France); Laboratoire Génie des Matériaux, Ecole Militaire Polytechnique, BP 17 Bordj El-Bahri Algiers (Algeria); Taleb, L., E-mail: lakhdar.taleb@insa-rouen.fr [INSA/GPM, CNRS UMR 6634, BP 08 avenue de l' université, 76801 Saint Etienne du Rouvray Cedex (France); Belouchrani, M.A., E-mail: nbelouch@yahoo.fr [Laboratoire Génie des Matériaux, Ecole Militaire Polytechnique, BP 17 Bordj El-Bahri Algiers (Algeria)

    2013-06-01

    The present work is devoted to study the anisotropic behavior of an extruded aluminum alloy under cyclic loading in axial and shear directions. In first, we have studied its elastoplastic behavior through the evolution of stress–strain loops, isotropic and kinematic hardening and we have associated this behavior with the evolution of its elastic adaptation (shakedown). In second, we have studied the behavior of the material in fatigue damage using the evolution of stiffness. Finally, microstructural investigations were performed on fractured surfaces using scanning electron microscope (SEM) in order to understand the evolution of fatigue damage during cyclic loading.

  6. Effect of neodymium on the as-extruded ZK20 magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    赵亚忠; 潘复生; 彭建; 王维青; 罗素琴

    2010-01-01

    The effect of Nd addition on the microstructure and mechanical properties of ZK20 magnesium alloy was investigated by room tensile test, optical microscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) in order to develop a magnesium alloy with higher ductility. Results showed that the crystal grains of as-extruded ZK20+0.5%Nd magnesium alloy were effectively refined, and the alloy exhibited higher strength and ductility, with the UTS of 237 MPa and the elongation of 32.8%, increasing by 5...

  7. Deactivation-resistant catalyst for selective catalyst reduction of NOx

    OpenAIRE

    Jensen, Anker Degn; Castellino, Francesco; Rams, Per Donskov; Pedersen, Jannik Blaabjerg; Putluru, Siva Sankar Reddy

    2011-01-01

    The present invention relates to a catalyst for selective catalytic reduction of NOx in alkali metal containing flue gas using ammonia as reductant, the catalyst comprising a surface with catalytically active sites, wherein the surface is at least partly coated with a coating comprising at least one metal oxide. In another aspect the present invention relates to the use of said catalyst and to a method of producing said catalyst. In addition, the present invention relates to a method of treat...

  8. Supported organoiridium catalysts for alkane dehydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Baker, R. Thomas; Sattelberger, Alfred P.; Li, Hongbo

    2013-09-03

    Solid supported organoiridium catalysts, a process for preparing such solid supported organoiridium catalysts, and the use of such solid supported organoiridium catalysts in dehydrogenation reactions of alkanes is provided. The catalysts can be easily recovered and recycled.

  9. Dynamics of Catalyst Nanoparticles

    DEFF Research Database (Denmark)

    Hansen, Thomas Willum; Cavalca, Filippo; Wagner, Jakob Birkedal

    under gas exposure, dynamic phenomena such as sintering and growth can be observed with sub-Ångstrøm resolution. Metal nanoparticles contain the active sites in heterogeneous catalysts, which are important for many industrial applications including the production of clean fuels, chemicals...... and pharmaceuticals, and the cleanup of exhaust from automobiles and stationary power plants. Sintering, or thermal deactivation, is an important mechanism for the loss of catalyst activity. In order to initiate a systematic study of the dynamics and sintering of nanoparticles, various catalytic systems have been...

  10. Nano Catalysts for Diesel Engine Emission Remediation

    Energy Technology Data Exchange (ETDEWEB)

    Narula, Chaitanya Kumar [ORNL; Yang, Xiaofan [ORNL; Debusk, Melanie Moses [ORNL; Mullins, David R [ORNL; Mahurin, Shannon Mark [ORNL; Wu, Zili [ORNL

    2012-06-01

    The objective of this project was to develop durable zeolite nanocatalysts with broader operating temperature windows to treat diesel engine emissions to enable diesel engine based equipment and vehicles to meet future regulatory requirements. A second objective was to improve hydrothermal durability of zeolite catalysts to at least 675 C. The results presented in this report show that we have successfully achieved both objectives. Since it is accepted that the first step in NO{sub x} conversion under SCR (selective catalytic reduction) conditions involves NO oxidation to NO{sub 2}, we reasoned that catalyst modification that can enhance NO oxidation at low-temperatures should facilitate NO{sub x} reduction at low temperatures. Considering that Cu-ZSM-5 is a more efficient catalyst than Fe-ZSM-5 at low-temperature, we chose to modify Cu-ZSM-5. It is important to point out that the poor low-temperature efficiency of Fe-ZSM-5 has been shown to be due to selective absorption of NH{sub 3} at low-temperatures rather than poor NO oxidation activity. In view of this, we also reasoned that an increased electron density on copper in Cu-ZSM-5 would inhibit any bonding with NH{sub 3} at low-temperatures. In addition to modified Cu-ZSM-5, we synthesized a series of new heterobimetallic zeolites, by incorporating a secondary metal cation M (Sc{sup 3+}, Fe{sup 3+}, In{sup 3+}, and La{sup 3+}) in Cu exchanged ZSM-5, zeolite-beta, and SSZ-13 zeolites under carefully controlled experimental conditions. Characterization by diffuse-reflectance ultra-violet-visible spectroscopy (UV-Vis), X-ray powder diffraction (XRD), extended X-ray absorption fine structure spectroscopy (EXAFS) and electron paramagnetic resonance spectroscopy (EPR) does not permit conclusive structural determination but supports the proposal that M{sup 3+} has been incorporated in the vicinity of Cu(II). The protocols for degreening catalysts, testing under various operating conditions, and accelerated aging

  11. Optimization of light yield by injecting an optical filler into the co-extruded hole of the plastic scintillation bar

    Science.gov (United States)

    Artikov, A.; Baranov, V.; Budagov, Ju.; Chokheli, D.; Davydov, Yu.; Glagolev, V.; Kharzheev, Yu.; Kolomoetz, V.; Shalugin, A.; Simonenko, A.; Tereshchenko, V.

    2016-05-01

    The light yield of 2-m long extruded scintillation bars (strips) are measured with cosmic muons as a function of the distance for different options of the light collection technique. The strips with a 2.6-mm diameter central co-extruded hole were made of polystyrene with the 2% PTP and 0.03% POPOP dopants at ISMA (Kharkov, Ukraine). It is shown that the optical transparent BC-600 or CKTN-MED(E) resin injected by a special technique into the co-extruded hole with a 1.0-mm or 1.2-mm Kuraray Y11 (200) MC wave-length shifting (WLS) fiber in it improves light collection by a factor of 1.6–1.9 against the ``dry'' case.

  12. Mechanical properties of equal channel angular pressed powder extrudates of a rapidly solidified hypereutectic Al-20 wt% Si alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Seung Chae [Department of Metallurgical Engineering, Chungnam National University, Yuseoung, Daejeon 305-764 (Korea, Republic of); Hong, Soon-Jik [Division of Advanced Engineering, Kongju National University, Kongju, 314-701 (Korea, Republic of); Korean Atomic Energy Research Institute, Yuseoung, Daejeon 305-353 (Korea, Republic of); Hong, Sun Ig [Department of Metallurgical Engineering, Chungnam National University, Yuseoung, Daejeon 305-764 (Korea, Republic of); Kim, Hyoung Seop [Department of Metallurgical Engineering, Chungnam National University, Yuseoung, Daejeon 305-764 (Korea, Republic of)], E-Mail: hskim@cnu.ac.kr

    2007-03-25

    The processing and mechanical properties of rapidly solidified and consolidated hypereutectic Al-20 wt% Si alloys were studied. A bulk form of rapidly solidified Al-20 wt% Si alloy was prepared by extruding gas atomized powders having a powder size of 106-145 {mu}m. Powder extrudates were subsequently equal channel angular pressed up to eight repetitive route C passes to refine matrix microstructure and Si particles by imposing severe plastic deformation. The microstructures of the gas atomized powders, extrudates and equal channel angular pressed samples were investigated via a scanning electron microscope. The mechanical properties of the bulk samples were measured by compressive tests. Equal channel angular pressing was found to be effective in matrix grain and Si particle refinement, which enhanced the strength of the Al-20 wt% Si alloy without deteriorating ductility in a range of experimental strain of up to 30%.

  13. Extruded Bread Classification on the Basis of Acoustic Emission Signal With Application of Artificial Neural Networks

    Science.gov (United States)

    Świetlicka, Izabela; Muszyński, Siemowit; Marzec, Agata

    2015-04-01

    The presented work covers the problem of developing a method of extruded bread classification with the application of artificial neural networks. Extruded flat graham, corn, and rye breads differening in water activity were used. The breads were subjected to the compression test with simultaneous registration of acoustic signal. The amplitude-time records were analyzed both in time and frequency domains. Acoustic emission signal parameters: single energy, counts, amplitude, and duration acoustic emission were determined for the breads in four water activities: initial (0.362 for rye, 0.377 for corn, and 0.371 for graham bread), 0.432, 0.529, and 0.648. For classification and the clustering process, radial basis function, and self-organizing maps (Kohonen network) were used. Artificial neural networks were examined with respect to their ability to classify or to cluster samples according to the bread type, water activity value, and both of them. The best examination results were achieved by the radial basis function network in classification according to water activity (88%), while the self-organizing maps network yielded 81% during bread type clustering.

  14. Effect of Zn on mechanical property and corrosion property of extruded Mg-Zn-Mn alloy

    Institute of Scientific and Technical Information of China (English)

    YIN Dong-song; ZHANG Er-lin; ZENG Song-yan

    2008-01-01

    The effect of Zn on the microstructure, the mechanical property and the corrosion property in simulated body fluid(SBF) of an extruded Mg-Mn alloy was studied. The results indicate that the addition of Zn element can significantly refine the grain size of the extruded Mg-Mn alloy. When Zn content is increased from 0% to 3%, the grain size decreases from 12 μm to 4 μm. Meanwhile, the mechanical properties also increase remarkably with increasing Zn content. When Zn content is 3%, the ultimate tensile strength and the yield strength are increased by 54.7 MPa and 69.7 MPa, respectively. Zn can also improve the anti-corrosion property of the alloy. The best anti-corrosion property is obtained with 1% Zn. However, further increase of Zn content up to 3% deteriorates the corrosion property. Finally, the influence mechanism of Zn on the microstructure, the mechanical property and the corrosion property was discussed.

  15. Microstructures, mechanical properties and corrosion resistances of extruded Mg-Zn-Ca-xCe/La alloys.

    Science.gov (United States)

    Tong, L B; Zhang, Q X; Jiang, Z H; Zhang, J B; Meng, J; Cheng, L R; Zhang, H J

    2016-09-01

    Magnesium alloys are considered as good candidates for biomedical applications, the influence of Ce/La microalloying on the microstructure, mechanical property and corrosion performance of extruded Mg-5.3Zn-0.6Ca (wt%) alloy has been investigated in the current study. After Ce/La addition, the conventional Ca2Mg6Zn3 phases are gradually replaced by new Mg-Zn-Ce/La-(Ca) phases (T1'), which can effectively divide the Ca2Mg6Zn3 phase. The Ca2Mg6Zn3/T1' structure in Mg-Zn-Ca-0.5Ce/La alloy is favorably broken into small particles during the extrusion, resulting in an obvious refinement of secondary phase. The dynamic recrystallized grain size is dramatically decreased after 0.5Ce/La addition, and the tensile yield strength is improved, while further addition reverses the effect, due to the grain coarsening. However, the corrosion resistance of extruded Mg-Zn-Ca alloy deteriorates after Ce/La addition, because the diameter of secondary phase particle is remarkably decreased, which increases the amount of cathodic sites and accelerates the galvanic corrosion process. PMID:27179307

  16. Nutritional assessment in vitro and in vivo of raw and extruded peas (Pisum sativum L.).

    Science.gov (United States)

    Alonso, R; Grant, G; Dewey, P; Marzo, F

    2000-06-01

    The effects of extrusion cooking on the nutritional properties of Pisum sativum L. have been evaluated in vitro and in vivo. The treatment greatly elevated protein and starch digestibility in vitro. Also, the amounts of intact starch diminished while total free sugars increased. In addition, the levels of antinutritional factors, such as protease inhibitors and lectins, were greatly decreased. Concentrations of methionine and cystine were low in raw peas and were further reduced by extrusion treatment. The nutritional performance of rats fed extruded pea diets for 15 days was no better than that of rats given raw pea diet. This was due to the overriding effects of amino acid deficiencies in the diets. Weight gains by rats fed extruded pea diets supplemented with amino acids were, however, much higher than those achieved by rats fed supplemented raw pea diets. Food transformation index and protein efficiency ratio values were also greatly improved. Extrusion treatment did therefore significantly improve the nutritional quality of peas. PMID:10888538

  17. Evolution of microstructure and tensile properties of extruded Mg-4Zn-1Y alloy

    Institute of Scientific and Technical Information of China (English)

    李吉宝; 王峰; 毛萍莉; 刘正

    2014-01-01

    In order to investigate the effect of extrusion on Mg-4Zn-1Y alloy, microstructure and mechanical properties were analyzed by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), en-ergy dispersive spectrum (EDS) and tensile testing. The results indicated that the microstructure was obviously refined by extrusion and dynamic recrystallization. The second phases were dynamic precipitated and distributed more dispersively through extrusion. W-Phases (Mg3Zn3Y2) were twisted and broken, while I-Phases (Mg3Zn6Y) were spheroidized by deformation. Twin bands were formed to achieve the large deformation and hinder the slip of dislocations effectively to improve tensile properties. The tensile strength and elon-gation of extruded Mg-4Zn-1Y alloy were 254.94 MPa and 17.9%respectively which were improved greatly compared with those of as-cast alloy. The strengthening mechanisms of the extruded alloy were mainly fine-grain strengthening and distortion strengthening.

  18. Corrosion Behavior of Extruded near Eutectic Al-Si-Mg and 6063 Alloys

    Institute of Scientific and Technical Information of China (English)

    Yuna Wu; Hengcheng Liao

    2013-01-01

    In this work,a comparison study on corrosion behavior of extruded near eutectic Al-12.3%Si-0.26%Mg and 6063 alloys has been carried out by mass loss test in 4% H2SO4 aqueous solution in the open air and potentiodynamic polarization test in 3.5 wt.% NaCl aqueous solution.Results indicate that the corrosion resistance of the near eutectic Al-Si-Mg alloy is less than that of 6063 alloy.Macro/microscopy and scanning electron microscopy results clearly show the difference of the corrosion progress of these two alloys in 4% H2SO4 aqueous solution.The corrosion type of 6063 alloy is pitting corrosion.The Mg2Si and AlFeSi particles and surface defects act as nucleation sites for pitting,and the amount and distribution of them have a significant effect on the pitting behavior.For the near eutectic alloy,there are two types of corrosion cells.One is between the extruded primary α-Al and the eutectic,the other is between the eutectic Al and eutectic Si particles.Combination of these two types of corrosion cells leads to a lower corrosion resistance,a higher mass loss of the near eutectic alloy compared with 6063 alloy,and the formation of the paralleling corroded grooves.

  19. Twin-Screw Extruder and Pellet Accelerator Integration Developments for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Meitner, Steven J [ORNL; Baylor, Larry R [ORNL; Combs, Stephen Kirk [ORNL; Fehling, Dan T [ORNL; Foust, Charles R [ORNL; McGill, James M [ORNL; Rasmussen, David A [ORNL; Maruyama, So [ITER Organization, Cadarache, France

    2011-01-01

    The ITER pellet injection system consisting of a twinscrew frozen hydrogen isotope extruder, coupled to a combination solenoid actuated pellet cutter and pneumatic pellet accelerator, is under development at the Oak Ridge National Laboratory. A prototype extruder has been built to produce a continuous solid deuterium extrusion and will be integrated with a secondary section, where pellets are cut, chambered, and launched with a single-stage pneumatic accelerator into the plasma through a guide tube. This integrated pellet injection system is designed to provide 5 mm fueling pellets, injected at a rate up to 10 Hz, or 3 mm edge localized mode (ELM) triggering pellets, injected at higher rates up to 20 Hz. The pellet cutter, chamber mechanism, and the solenoid operated pneumatic valve for the accelerator are optimized to provide pellet velocities between 200-300 m/s to ensure high pellet survivability while traversing the inner wall fueling guide tubes, and outer wall ELMpacing guide tubes. This paper outlines the current twin-screwextruder design, pellet accelerator design, and the integrationrequired for both fueling and ELM pacing pellets.

  20. Microstructural evolution during the annealing of an extruded AZ31 magnesium alloy

    International Nuclear Information System (INIS)

    Research highlights: The manuscript presents an experimental investigation on the microstructure and texture development during a post-extrusion heat treatment of an AZ31 alloy, by using neutron as well as electron diffraction techniques. The results show clearly the texture changes from the fibre to the fibre component with grain growth and the role of internal misorientation as an important driving force for the grain growth. The preferred growth of the grains having the fibre component leads to a transition of the main texture component to the corresponding global texture. - Abstract: Microstructural evolution during the annealing of AZ31 extruded rod at 400 oC has been examined by employing neutron diffraction and electron backscatter diffraction (EBSD). In the as-extruded bar, equiaxed grains smaller than 5 μm and large elongated grains having significant degrees of internal misorientation are oriented mainly with parallel to the extrusion direction. Rapid grain growth occurs within the 180 s annealing period at 400 oC at the expense of the small grains with the internal orientation gradient as driving force. After short time annealing, small equiaxed grains are formed inside the large elongated grains, and grains having parallel to the extrusion direction show preferred growth. As a result, a transition of the main texture component to the component occurs after annealing for 1800 s at 400 oC.

  1. Effect of extruding full-fat soy flakes on trans fat content.

    Science.gov (United States)

    Feng, Hongxia; Sui, Xiaonan; Chang, Yunhe; Qi, Baokun; Zhang, Yan; Li, Yang; Jiang, Lianzhou

    2014-01-01

    To evaluate the effects of extrusion process on the trans fatty acids (TFAs) formation in soybean crude oils, three different extrusion parameters, namely, extrusion temperature (80-160 °C), feed moisture (10-26%), and screw speed (100-500 rpm), were carried out. It was found that only five different types of TFAs were detected out using gas chromatography-mass spectrometry. Before the extrusion started, the initial amount of total TFAs was 3.04 g/100 g. However, after extruding under every level of any variable, the total amounts of TFAs were significantly higher than those in the control sample (P extrusion temperature into account, we can find that the highest amount of total of trans fatty acid (TTFA) was 1.62 times the amount of that in the control sample, whereas the lowest amount of TTFA was 1.54 times the amount of that in the control sample. Importantly, it was observed that the amounts of every type of trans fatty acid were not continuously increasing with the increase of the level of any extrusion variable. This phenomenon demonstrated that the formation and diversification were intricate during extruding process and need to be further studied. PMID:25202725

  2. Effect of Extruding Full-Fat Soy Flakes on Trans Fat Content

    Directory of Open Access Journals (Sweden)

    Hongxia Feng

    2014-01-01

    Full Text Available To evaluate the effects of extrusion process on the trans fatty acids (TFAs formation in soybean crude oils, three different extrusion parameters, namely, extrusion temperature (80–160°C, feed moisture (10–26%, and screw speed (100–500 rpm, were carried out. It was found that only five different types of TFAs were detected out using gas chromatography-mass spectrometry. Before the extrusion started, the initial amount of total TFAs was 3.04 g/100 g. However, after extruding under every level of any variable, the total amounts of TFAs were significantly higher than those in the control sample (P<0.05. For example, taking the effect of extrusion temperature into account, we can find that the highest amount of total of trans fatty acid (TTFA was 1.62 times the amount of that in the control sample, whereas the lowest amount of TTFA was 1.54 times the amount of that in the control sample. Importantly, it was observed that the amounts of every type of trans fatty acid were not continuously increasing with the increase of the level of any extrusion variable. This phenomenon demonstrated that the formation and diversification were intricate during extruding process and need to be further studied.

  3. Electrical resistivity, wear map and modeling of extruded tungsten reinforced copper composite

    International Nuclear Information System (INIS)

    Highlights: • Wear tests were conducted on Cu and Cu–W sintered and extruded composite. • Analyzed wear rate and coefficient of friction with respect to sliding distance. • SEM observations were analyzed to evaluate the worn surface and debris particles. • Design expert software was used to develop the map and model. - Abstract: The present work includes the effect of W addition in improving the properties of Cu with the help of high-energy mechanical alloying. Composite preforms of (5–15 W) with copper were fabricated by Powder Metallurgy (P/M) method. The preforms were sintered at 850 °C, subsequently the furnace was cooled and again the specimens were hot extruded to get 92% preform density. Four point probe tester, Scanning Electron Microscope, Energy Dispersive Spectrum and pin on-disc system were used to evaluate electrical conductivity, characterization and tribological property of Cu–W composite respectively. The various stages in dominant oxidation and delamination wear mechanism was clearly discussed. The wear rate and coefficient of friction decreased with increase in load and sliding distance. Design expert software was used to develop contour map, mathematical model and useful conclusions were made

  4. Microstructure and properties of hot extruded AZ31-0.25%Sb Mg-alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effects of hot extrusion treatment on the microstructure and mechanical properties of AZ31-0.25%Sb Mg alloy were mvestlgated by means of mechanical properties measurement and microstructure observation.The results show that the (UTS) and yield tensile strength(YTS) of the alloy are obviously enhanced by hot extrusion treatment,and the enhanced extent of UTS and YTS increases with the decrease of hot extrusion temperature,moreover,the YTS value of the alloy at RT,after extruded at 220℃,increases up to 131.4%,which attributes to the finer grains resulted from the dynamic recrystallization occurred during hot extrusion.As not extrusion goes on,the slipping and concentration of dislocations continue to occur within the finer grains,which promotes the formation of the subgrains in the alloy.The deformation features of the extruded alloy during tensile deformation at RT are the twinning deformation and dislocation slipping in the twinning regions.Moreover,the deformation mechanisms of the alloy are a dislocation activation on the basal plane and a+c dislocation activation on the pyramidal planes.

  5. HIGH-DENSITY, BIO-COMPATIBLE, AND HERMETIC ELECTRICAL FEEDTHROUGHS USING EXTRUDED METAL VIAS

    Energy Technology Data Exchange (ETDEWEB)

    Shah, K G; Delima, T; Felix, S; Sheth, H; Tolosa, V; Tooker, A; Pannu, S S

    2012-03-28

    Implanted medical devices such as pacemakers and neural prosthetics require that the electronic components that power these devices are protected from the harsh chemical and biological environment of the body. Typically, the electronics are hermetically sealed inside a bio-compatible package containing feedthroughs that transmit electrical signals, while being impermeable to particles or moisture. We present a novel approach for fabricating one of the highest densities of biocompatible hermetic feedthroughs in alumina (Al{sub 2}O{sub 3}). Alumina substrates with laser machined vias of 200 {micro}m pitch were conformally metallized and lithographically patterned. Hermetic electrical feedthroughs were formed by extruding metal stud-bumps partially through the vias. Hermeticity testing showed leak rates better than 9 x 10{sup -10} torr-l/s. Based on our preliminary results and process optimization, this extruded metal via approach is a high-density, low temperature, cost-effective, and robust method of miniaturizing electrical feedthroughs for a wide range of implantable bio-medical device applications.

  6. HIGH-DENSITY, BIO-COMPATIBLE, AND HERMETIC ELECTRICAL FEEDTHROUGHS USING EXTRUDED METAL VIAS

    Energy Technology Data Exchange (ETDEWEB)

    Tooker, A; Shah, K; Tolosa, V; Sheth, H; Felix, S; Delima, T; Pannu, S

    2012-03-29

    Implanted medical devices such as pacemakers and neural prosthetics require that the electronic components that power these devices are protected from the harsh chemical and biological environment of the body. Typically, the electronics are hermetically sealed inside a bio-compatible package containing feedthroughs that transmit electrical signals, while being impermeable to particles or moisture. We present a novel approach for fabricating one of the highest densities of biocompatible hermetic feedthroughs in alumina (Al{sub 2}O{sub 3}). Alumina substrates with laser machined vias of 200 {mu}m pitch were conformally metallized and lithographically patterned. Hermetic electrical feedthroughs were formed by extruding metal studbumps partially through the vias. Hermeticity testing showed leak rates better than 9x10{sup -10} torr-l/s. Based on our preliminary results and process optimization, this extruded metal via approach is a high-density, low temperature, cost-effective, and robust method of miniaturizing electrical feedthroughs for a wide range of implantable bio-medical device applications.

  7. Low temperature calcium hydroxide treatment enhances anaerobic methane production from (extruded) biomass.

    Science.gov (United States)

    Khor, Way Cern; Rabaey, Korneel; Vervaeren, Han

    2015-01-01

    Ca(OH)2 treatment was applied to enhance methane yield. Different alkali concentration, incubation temperature and duration were evaluated for their effect on methane production and COD conversion efficiency from (non-)extruded biomass during mesophilic anaerobic digestion at lab-scale. An optimum Ca(OH)2 pretreatment for grass is found at 7.5% lime loading at 10°C for 20h (37.3% surplus), while mild (50°C) and high temperatures perform sub-optimal. Ca(OH)2 post-treatment after fast extrusion gives an additional surplus compared to extruded material of 15.2% (grass), 11.2% (maize straw) and 8.2% (sprout stem) regarding methane production. COD conversion improves accordingly, with additional improvements of 10.3% (grass), 9.0% (maize straw) and 6.8% (sprout stem) by Ca(OH)2 post-treatment. Therefore, Ca(OH)2 pretreatment and post-treatment at low temperature generate an additional effect regarding methane production and COD conversion efficiency. Fast extrusion gives a higher energy efficiency ratio compared to slow extrusion. PMID:25461001

  8. Cytotoxic effect of the debris apically extruded during three different retreatment procedures.

    Science.gov (United States)

    Silva, Emmanuel J N L; Brito, Mônica E; Ferreira, Vivian D; Belladonna, Felipe G; Neves, Aline A; Senna, Plinio M; De-Deus, Gustavo

    2016-01-01

    We evaluated the cytotoxic effects of the debris apically extruded during root canal retreatment on primary human osteoblast (HOb) cells in vitro. TNF-α and IL-1β levels were also measured. We examined three different techniques: conventional hand-files, and Mtwo and Reciproc retreatments. Filled mandibular incisors were prepared for a cytotoxicity assay in an experimental root model. The material was divided into three groups according to the technique used. Ten teeth were used as control. HOb cells were exposed to the extruded content and cytotoxicity was evaluated using the MTT test (assessing cell metabolic activity). TNF-α and IL-1β production was also analyzed using enzyme-linked immunosorbent assay. Then, all the teeth were radiographed and the residual filling material was quantified. Data were subjected to analysis of variance (ANOVA) and Tukey's test (P endodontic retreatment techniques led to a significant upregulation of IL-1β levels (P 0.05). The Reciproc system required less time than the other two methods to remove the root-filling materials (P endodontic retreatment with Reciproc was the least cytotoxic and the least time-consuming method of gutta-percha and sealer removal. (J Oral Sci 58, 211-217, 2016). PMID:27349542

  9. Changes in physical properties of extruded sour cassava starch and quinoa flour blend snacks

    Directory of Open Access Journals (Sweden)

    Lívia Giolo Taverna

    2012-12-01

    Full Text Available Given the broad acceptance of sour cassava starch biscuits in Brazil and the nutritional quality of quinoa flour, this study aimed to evaluate the effect of extrusion temperature, screw speed, moisture, and amount of quinoa flour on the physical properties of puffed snacks. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Effects of moisture and amount of quinoa flour on the expansion index and specific volume of snacks were observed. There was a pronounced increase in water solubility index of blends with the extrusion process with significant effects of all process parameters on the WSI. Higher water absorption index (WAI was observed under high temperature, low moisture, and lower quinoa flour amount. Temperature and amount of quinoa flour influenced the color of the snacks. A positive quadratic effect of quinoa flour on hardness of products was observed. Blends of sour cassava starch and quinoa flour have good potential for use as raw material in production of extruded snacks with good physical properties.

  10. Intrinsic catalytic properties of extruded clay honeycomb monolith toward complete oxidation of air pollutants.

    Science.gov (United States)

    Assebban, Mhamed; El Kasmi, Achraf; Harti, Sanae; Chafik, Tarik

    2015-12-30

    The present work highlights the intrinsic catalytic properties of extruded clay honeycomb monolith toward complete oxidation of various air pollutants namely CO, methane, propane, acetylene, propene, n-butene, methanol, ethanol, n-propanol, n-butanol, acetone, dimethyl ether, benzene, toluene, o-xylene, monochlorobenzene and 1,2-dichlorobenzene. Total catalytic conversion was achieved for all tested compounds with different behaviors depending on pollutants' structural and chemical nature. The comparison of T50 values obtained from light-off curves allowed the establishment of the following reactivity sequence: ketone>alcohol>ether>CO>alkyne>aromatic>alkene>chlorinated aromatic>alkane. The intrinsic catalytic performances of the natural clay was ascribed to the implication of a quite complex mixture constituted by OH groups (Brønsted acids) and coordinately-unsaturated cations, such as Al(3+), Fe(3+) and Fe(2+) (Lewis acids). Hence, the combination of the clay's intrinsic catalytic performances and easier extrudability suggests a promissory potential for application in air pollution control. PMID:26259164

  11. Microstructures, mechanical and corrosion properties and biocompatibility of as extruded Mg-Mn-Zn-Nd alloys for biomedical applications.

    Science.gov (United States)

    Zhou, Ying-Long; Li, Yuncang; Luo, Dong-Mei; Ding, Yunfei; Hodgson, Peter

    2015-04-01

    Extruded Mg-1Mn-2Zn-xNd alloys (x=0.5, 1.0, 1.5 mass %) have been developed for their potential use as biomaterials. The extrusion on the alloys was performed at temperature of 623K with an extrusion ratio of 14.7 under an average extrusion speed of 4mm/s. The microstructure, mechanical property, corrosion behavior and biocompatibility of the extruded Mg-Mn-Zn-Nd alloys have been investigated in this study. The microstructure was examined using X-ray diffraction analysis and optical microscopy. The mechanical properties were determined from uniaxial tensile and compressive tests. The corrosion behavior was investigated using electrochemical measurement. The biocompatibility was evaluated using osteoblast-like SaOS2 cells. The experimental results indicate that all extruded Mg-1Mn-2Zn-xNd alloys are composed of both α phase of Mg and a compound of Mg7Zn3 with very fine microstructures, and show good ductility and much higher mechanical strength than that of cast pure Mg and natural bone. The tensile strength and elongation of the extruded alloys increase with an increase in neodymium content. Their compressive strength does not change significantly with an increase in neodymium content. The extruded alloys show good biocompatibility and much higher corrosion resistance than that of cast pure Mg. The extruded Mg-1Mn-2Zn-1.0Nd alloy shows a great potential for biomedical applications due to the combination of enhanced mechanical properties, high corrosion resistance and good biocompatibility. PMID:25686931

  12. Catalysts for Environmental Remediation

    DEFF Research Database (Denmark)

    Abrams, B. L.; Vesborg, Peter Christian Kjærgaard

    2013-01-01

    The properties of catalysts used in environmental remediation are described here through specific examples in heterogeneous catalysis and photocatalysis. In the area of heterogeneous catalysis, selective catalytic reduction (SCR) of NOx was used as an example reaction with vanadia and tungsta on...

  13. Tight bifunctional hierarchical catalyst.

    Science.gov (United States)

    Højholt, Karen T; Vennestrøm, Peter N R; Tiruvalam, Ramchandra; Beato, Pablo

    2011-12-28

    A new concept to prepare tight bifunctional catalysts has been developed, by anchoring CoMo(6) clusters on hierarchical ZSM-5 zeolites for simultaneous use in HDS and hydrocracking catalysis. The prepared material displays a significant improved activity in HDS catalysis compared to the impregnated counterpart. PMID:22048337

  14. Hydrogen evolution reaction catalyst

    Science.gov (United States)

    Subbaraman, Ram; Stamenkovic, Vojislav; Markovic, Nenad; Tripkovic, Dusan

    2016-02-09

    Systems and methods for a hydrogen evolution reaction catalyst are provided. Electrode material includes a plurality of clusters. The electrode exhibits bifunctionality with respect to the hydrogen evolution reaction. The electrode with clusters exhibits improved performance with respect to the intrinsic material of the electrode absent the clusters.

  15. EVALUATION OF PULP AND PAPER MAKING CHARACTERISTICS OF RICE STEM FIBERS PREPARED BY TWIN-SCREW EXTRUDER PULPING

    OpenAIRE

    Alireza Talebizadeh; Pejman Rezayati-Charani

    2010-01-01

    Twin-screw extrusion pulping is a new approach to the manufacture of pulp for paper production, designed for non-wood feedstocks. In this research, the production of pulp from rice stem with a newly fabricated twin-screw extruder was investigated. Extrusion pulping of rice stem was conducted following a central composite design using a two-level factorial plan involving three process variables (pretreatment NaOH concentration: 0.4, 0.8, 1.2%; extrusion temperature: 40, 60, 80 oC; and extruder...

  16. Novel method of measuring polymer melt viscosity using a short length of single screw extruder at the closed discharge state

    Science.gov (United States)

    Kim, Myung-Ho; Kim, Bo-Kyung; Kang, Seok-Jin; Kim, Moon Sung; Choi, Sunwoong

    2016-03-01

    Theory of single screw extruders has been used for analyzing the processing characteristics of various polymeric fabricated such material as plastics, rubber, and food products. Recently this theory extended to measuring the polymer melt viscosity using the closed discharging state of the short single screw extruder. The batch wise operation of the closed discharged state change the complex extrusion characteristic equation into simple calculation form of shear rate and viscosity equation, which related between the geometrical factors and the screw speed and the axial pressure generation, respectively.

  17. Effects of temperature, moisture and residence time in the properties of full fat soybean flour produced in a twin extruder.

    Science.gov (United States)

    Serna-Saldivar, S O; Cabral, L C

    1997-03-01

    Soybeans were dehulled, roll-milled into grits, conditioned to 18 or 21% moisture and continuously cooked in a twin extruder at three temperature programs and two residence times. The resulting extrudates were further dried and roll-milled into flour and characterized for their physical, chemical and functional properties. The urease activity and nitrogen solubility index (NSI) decreased with increased extrusion temperature, residence time and soybean grits moisture content. The best pre-cooked full fat flours had a urease activity lower than 0.2 and a NSI higher than 15%. PMID:9429645

  18. Technology development for iron Fischer-Tropsch catalysts

    Energy Technology Data Exchange (ETDEWEB)

    O`Brien, R.J.; Raje, A.; Keogh, R.A. [and others

    1995-12-31

    The objective of this research project is to develop the technology for the production of physically robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry phase synthesis reactor development. The catalysts that are developed shall be suitable for testing in the Advanced Fuels Development Facility at LaPorte, Texas, to produce either low-or high-alpha product distributions. Previous work by the offeror has produced a catalyst formulation that is 1.5 times as active as the {open_quotes}standard-catalyst{close_quotes} developed by German workers for slurry phase synthesis. In parallel, work will be conducted to design a high-alpha iron catalyst this is suitable for slurry phase synthesis. Studies will be conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors will be studied at the laboratory scale. Catalyst performance will be determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  19. Effect of feeding extruded flaxseed with different forage: concentrate ratios on the performance of dairy cows.

    Science.gov (United States)

    Neveu, C; Baurhoo, B; Mustafa, A

    2013-06-01

    Twenty Holstein cows were used in a Latin square design experiment with a 2×2 factorial arrangement to determine the effects of extruded flaxseed (EF) supplementation with 2 different forage to concentrate ratios on the performance of dairy cows. Extruded flaxseed diets contained 9% (dry matter basis) EF product which consisted of 75% EF and 25% ground alfalfa meal. Four lactating Holsteins cows fitted with rumen fistulae were used to determine the effects of dietary treatments on ruminal fermentation. Intakes of dry matter and crude protein were not influenced by dietary treatments. However, neutral detergent fiber intake was greater for the high-forage (8.4 kg/d) than the low-forage (7.8 kg/d) diet. Milk yield (average 40.2 kg/d) was similar for all dietary treatments. However, cows fed the high-forage diets produced milk with higher fat (3.76 vs. 2.97%) and total solids (12.58 vs. 11.95%) concentrations, but lower protein (3.19 vs. 3.33%) and lactose (4.66 vs. 4.72%) contents. Ruminal pH and total volatile fatty acid concentration were not affected by dietary treatments. However, feeding high forage relative to low forage diets increased molar proportion of acetate but decreased that of propionate. Ruminal NH3-N was reduced by feeding high forage relative to low forage diets. Milk fatty acid composition was altered by both forage level and EF supplementation. Feeding diets containing EF or low forage reduced the concentrations of saturated fatty acids and increased those of mono-unsaturated fatty acids. Concentrations of poly-unsaturated fatty acids were increased by feeding EF or low-forage diets. Extruded flaxseed supplementation increased milk fat α-linolenic acid content by 100% and conjugated linoleic acid by 54%. It was concluded that differences in animal performance and ruminal fermentation observed in this study were mostly due to differences in forage to concentrate ratio. However, EF supplementation caused most of the differences observed in milk

  20. Effect of extrusion on the antioxidant capacity and color attributes of expanded extrudates prepared from purple potato and yellow pea flour mixes.

    Science.gov (United States)

    Nayak, Balunkeswar; Berrios, Jose De J; Powers, Joseph R; Tang, Juming

    2011-08-01

    Foods with antioxidant capacity provide protection against cardio-vascular, certain forms of cancers, and Alzheimer's diseases caused by oxidative damages and contribute health benefits. The effect of extrusion cooking on the antioxidant capacity and color attributes of extruded products prepared from 3 selected formulations of purple potato and yellow pea flours using a co-rotating twin screw extruder were studied. Expansion ratios of the extruded products varied from 3.93 to 4.75. The total antioxidant capacities (TAC) of the extruded products, using DPPH assay, were 3769 to 4116 μg trolox equivalent/g dry weight sample and not significantly different (P > 0.05) from their respective raw formulations. The total phenolic contents (TP) of the extruded products varied from 2088 to 3766 μg of gallic acid equivalent/g dry weight sample and retained 73% to 83% of the TP from the raw formulations after extrusion. The total anthocyanins contents (TA) in the extrudates were 0.116 to 0.228 mg of malvidin-3-glucosides/g dry weight sample. Compared with their raw formulations, significant losses (60% to 70%) of the TA in the extruded products occurred due to extrusion cooking. Browning indices and color attributes such as brightness, chroma, and hue angle agreed with degradation of anthocyanins in the extruded products. However, extrusion cooking retained antioxidant capacities of the raw formulations in the extruded products either in their natural forms or degraded products with radical scavenging activity. This study demonstrated the potential for the production of puffed extruded food products with the improved antioxidant content from colored potatoes and pulse formulations. PMID:22417485

  1. Effect of Addition Sequence during Neutralization and Precipitation on Iron-based Catalysts for High Temperature Shift Reaction

    Institute of Scientific and Technical Information of China (English)

    Li Wei; Zhu Jianhua; Mou Zhanjun

    2007-01-01

    The preparation of the iron-based catalysts promoted by cobalt with a small amount of copper and aluminum for the high temperature shift reaction (HTS) with different sequences of adding catalyst raw materials during neutralization and precipitation was investigated. XRD,BET and particle size distribution (PSD) were used to characterize the prepared catalysts. It was found that the catalyst crystals were all γ-Fe2O3,and the intermediate of the catalyst after aging was Fe3O4. The crystallographic form of the catalyst and its intermediate was not affected by the addition sequence in the neutralization and precipitation process. The results showed that the specific surface area and the particle size of the catalysts depended on the addition sequence to the mother liquor. Cobalt with a small amount of copper and aluminum could increase the specific surface area and decrease the particle size of catalysts.

  2. COST ESTIMATES OF TWIN SCREW EXTRUDED PRODUCTS: TEXTURIZED WHEY PROTEIN SNACKS AND CORN-SOY BLEND USED FOR EMERGENCY FEEDING

    Science.gov (United States)

    The operating costs associated with twin screw extrusion cooking of various foods are fixed for a given size and production capacity for any class of products; the greater percentage of costs arise from the choice of ingredients and the product end use. For example, extruder texturized whey proteins...

  3. Microstructure, mechanical properties, corrosion behavior and hemolysis of as-extruded biodegradable Mg-Sn-Zn alloy

    Science.gov (United States)

    Hou, L.; Li, Z.; Pan, Y.; Du, L.; Li, X.; Zheng, Y.; Li, L.

    2016-04-01

    As biodegradable biomaterials, magnesium alloys have favorable physical, chemical and mechanical properties, as well as good biocompatibility, and are expected to totally biodegrade in the body environment. The microstructure, mechanical properties, corrosion behaviors and hemolysis of biodegradable Mg-Sn-Zn alloy were investigated under three extrusion ratios in the present work. It is revealed that the as-extruded microstructure is obviously refined with smaller grains compared with the as-cast structure while some twins form simultaneously. The tensile strengths of the as-extruded alloys fabricated with the higher extrusion ratio is 249MPa, and elongations is 16.3% respectively. Besides, the corrosion rate of as-extruded magnesium alloys increases with the increasing extrusion ratio. The hemolysis test result shows that the hemolysis rate of biodegradable magnesium alloys fabricated with the higher extrusion ratio is 4.8%, when hemolysis rate lower than 5% has been demonstrated safe according to ISO 10993-4. In conclusion, the as-extruded biodegradable Mg-Sn-Zn alloy shows great potential as a novel medical implant material.

  4. EVALUATION OF PULP AND PAPER MAKING CHARACTERISTICS OF RICE STEM FIBERS PREPARED BY TWIN-SCREW EXTRUDER PULPING

    Directory of Open Access Journals (Sweden)

    Alireza Talebizadeh

    2010-06-01

    Full Text Available Twin-screw extrusion pulping is a new approach to the manufacture of pulp for paper production, designed for non-wood feedstocks. In this research, the production of pulp from rice stem with a newly fabricated twin-screw extruder was investigated. Extrusion pulping of rice stem was conducted following a central composite design using a two-level factorial plan involving three process variables (pretreatment NaOH concentration: 0.4, 0.8, 1.2%; extrusion temperature: 40, 60, 80 oC; and extruder rotational speed: 55, 70, 85 rpm. Responses of pulp and handsheets properties to the process variables were analyzed using statistical software (MINITAB 15. As the results show, pulping of rice stem fiber can be done at a relatively short pretreatment time about 4 hours and a low NaOH concentration about 0.8% by twin-screw extruder with limit extrusion temperature of about 80 oC and extruder rotational speed about 85 rpm. The effect of pretreatment solvent, NaOH, is greatly enhanced by increases in the extrusion temperature. Analysis of the results revealed that this process has suitable potential to be used to obtain a pulp with yields approximately equivalent to neutral sulfite semi-chemical pulping at fixed kappa number, which is applicable for fluting paper and linerboard production.

  5. Effects of some extrusion variables on physicochemical characteristics of extruded corn starch-passion fruit pulp (Passiflora edulis) snacks.

    Science.gov (United States)

    Cortés, R Nallely Falfán; Guzmán, Iñigo Verdalet; Martínez-Bustos, Fernando

    2014-12-01

    The aim of this work was to study the effect of the addition of passion fruit pulp (PFP: 0-7%), the variation of barrel temperature in the third zone extruder (BT: 80-140 °C) and feed moisture (FM:16-30%) in a blend of corn starch and passion fruit pulp on different physicochemical characteristics of directly expanded snacks by extrusion technology. Single-screw laboratory extruder and a central, composite, rotatable experimental design were used. Expansion index of extrudates ranged between 1.0 and 1.8. Decreasing of feed moisture (18%), passion fruit pulp concentration (1.42%) and the increasing of barrel temperature (127 °C) resulted in higher expansion index. The increasing of feed moisture and passion fruit pulp concentration resulted in higher penetration force values of extrudates. The passion fruit pulp concentration showed a highly significant effect (p ≤ 0.01) on the L *, a * and b * parameters. Passion fruit pulp has a reasonable source of β-carotene, proteins and dietary fibers that can be added to expanded snacks. PMID:25447553

  6. 40 CFR 428.60 - Applicability; description of the medium-sized general molded, extruded, and fabricated rubber...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Applicability; description of the medium-sized general molded, extruded, and fabricated rubber plants subcategory. 428.60 Section 428.60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND...

  7. Impact of Dry Solids and Bile Acid Concentrations on Bile Acid Binding Capacity of Extruded Oat Cereals

    Science.gov (United States)

    Extruded breakfast cereals (EBC), processed from two oat lines, N979-5-2-4 (N979) and ‘Jim’, with beta-glucan concentrations of 8.7 and 4.9%, respectively, were used to determine the impact of dry solids (DS) and bile acid (BA) concentrations on in vitro BA binding efficiency. A full fractional fact...

  8. Catalyst Deactivation: Control Relevance of Model Assumptions

    Directory of Open Access Journals (Sweden)

    Bernt Lie

    2000-10-01

    Full Text Available Two principles for describing catalyst deactivation are discussed, one based on the deactivation mechanism, the other based on the activity and catalyst age distribution. When the model is based upon activity decay, it is common to use a mean activity developed from the steady-state residence time distribution. We compare control-relevant properties of such an approach with those of a model based upon the deactivation mechanism. Using a continuous stirred tank reactor as an example, we show that the mechanistic approach and the population balance approach lead to identical models. However, common additional assumptions used for activity-based models lead to model properties that may deviate considerably from the correct one.

  9. Extrusion and Extruded Products: Changes in Quality Attributes as Affected by Extrusion Process Parameters: A Review.

    Science.gov (United States)

    Alam, M S; Kaur, Jasmeen; Khaira, Harjot; Gupta, Kalika

    2016-01-01

    Extrusion of foods is an emerging technology for the food industries to process and market a large number of products of varying size, shape, texture, and taste. Extrusion cooking technology has led to production of wide variety of products like pasta, breakfast cereals, bread crumbs, biscuits, crackers, croutons, baby foods, snack foods, confectionery items, chewing gum, texturized vegetable protein (TVP), modified starch, pet foods, dried soups, dry beverage mixes etc. The functional properties of extruded foods plays an important role for their acceptability which include water absorption, water solubility, oil absorption indexes, expansion index, bulk density and viscosity of the dough. The aim of this review is to give the detailed outlines about the potential of extrusion technology in development of different types of products and the role of extrusion-operating conditions and their effect on product development resulting in quality changes i.e physical, chemical, and nutritional, experienced during the extrusion process. PMID:25574813

  10. Multiparametric atomic force microscopy imaging of single bacteriophages extruding from living bacteria.

    Science.gov (United States)

    Alsteens, David; Trabelsi, Heykel; Soumillion, Patrice; Dufrêne, Yves F

    2013-01-01

    Force-distance (FD) curve-based atomic force microscopy is a valuable tool to simultaneously image the structure and map the biophysical properties of biological samples at the nanoscale. Traditionally, FD-based atomic force microscopy has been severely limited by its poor temporal and lateral resolutions. Here we report the use of advanced FD-based technology combined with biochemically sensitive tips to image filamentous bacteriophages extruding from living bacteria at unprecedented speed and resolution. Directly correlated multiparametric images of the structure, adhesion and elasticity of infected bacteria demonstrate that the sites of assembly and extrusion localize at the bacterial septum in the form of soft nanodomains surrounded by stiff cell wall material. The quantitative nano-bio-imaging method presented here offers a wealth of opportunities for mapping the physical properties and molecular interactions of complex biosystems, from viruses to tissues. PMID:24336094

  11. Effects of cryogenic treatment on mechanical properties of extruded Mg-Gd-Y-Zr(Mn) alloys

    Institute of Scientific and Technical Information of China (English)

    XIONG Chuang-xian; ZHANG Xin-ming; DENG Yun-lai; XIAO Yang; DENG Zhen-zhen; CHEN Bu-xiang

    2007-01-01

    The influence of cryogenic treatment on the mechanical properties of the extruded Mg-Gd-Y-Zr(Mn) alloys was investigated by the tensile tests, scanning electron microscopy(SEM), transmission electron microscopy(TEM), and energy dispersive X-ray spectroscopy (EDS). The results show that the mechanical properties of both alloys are improved greatly during the in situ tensile test by soaking the samples in liquid nitrogen for 10 min. The ultimate tensile strength, yield tensile strength and elongation of cryogenic treated magnesium alloy added with zirconium or manganese are largely elevated. And remarkable microstructure change is observed in both alloys by cryogenic treatment. There are a large number of twins, rod-like, tree-like and chrysanthemum-like precipitated phases in the microstructures and the fracture surfaces exhibit the characteristics of ductile rupture when they are observed at room temperature.

  12. A versatile single-screw-extruder system designed for magnetic resonance imaging measurements

    Science.gov (United States)

    Amin, M. H. G.; Hanlon, A. D.; Hall, L. D.; Marriott, C.; Ablett, S.; Wang, W.; Frith, W. J.

    2003-10-01

    A versatile system has been developed for magnetic resonance imaging (MRI) measurements, in which a ceramic barrel/outer cylinder (0.04 m internal diameter) can be configured either as a single-screw extruder (polyetheretherketone (PEEK), length to diameter ratio 4.575, root diameter 0.03 m), or as a concentric-cylinder Couette device (PEEK, length 0.156 m, inner cylinder diameter 0.03 m). A second channel in the sample inlet allows two streams of fluid to be pumped simultaneously through the system for mixing. The shaft rotation speed can be set between 5 and 1200 revolutions per minute (rpm); the barrel and sample feeder can be separately thermostatted to +/-0.2 °C in the range of -10 to +60 °C via coolant jacket systems; samples with viscosity up to 10 Pa s can be pumped at rates up to 36 l h-1. This enables studies to be conducted with the system configured as a Couette device to provide knowledge of the rheological properties of complex fluids before more complicated studies of their flow and mixing with the system configured as a single-screw extruder. Bench and MRI measurements have been carried out to test the thermostat function of the system. The bench tests showed that the internal volume of the device reached thermal equilibrium after 1 h of running and could be maintained at constant temperature (within +/-0.2 °C) for periods of over 6 h. The MRI tests were conducted with the device configured in a Couette geometry for measurements of the flow velocities of pure glycerol and 1% aqueous sodium carboxymethylcellulose (CMC) in the range of 10-60 °C, and at various rotation speeds. Results showed that although the azimuthal velocity distributions versus the radius (v(r)) were independent of temperature for glycerol, there was strong temperature dependence for the CMC solution. On the latter the power-law index (n) from MRI data agreed well with the literature values for the same concentrations and temperatures, and showed n values increasing with

  13. Method of extruding and packaging a thin sample of reactive material including forming the extrusion die

    Science.gov (United States)

    Lewandowski, Edward F.; Peterson, Leroy L.

    1985-01-01

    This invention teaches a method of cutting a narrow slot in an extrusion die with an electrical discharge machine by first drilling spaced holes at the ends of where the slot will be, whereby the oil can flow through the holes and slot to flush the material eroded away as the slot is being cut. The invention further teaches a method of extruding a very thin ribbon of solid highly reactive material such as lithium or sodium through the die in an inert atmosphere of nitrogen, argon or the like as in a glovebox. The invention further teaches a method of stamping out sample discs from the ribbon and of packaging each disc by sandwiching it between two aluminum sheets and cold welding the sheets together along an annular seam beyond the outer periphery of the disc. This provides a sample of high purity reactive material that can have a long shelf life.

  14. Numerical simulation of upsetting-extruding process of dispersion strengthened copper welding electrode

    Institute of Scientific and Technical Information of China (English)

    WANG Meng-jun; ZHANG Ying-chun; HUANG Dian-yuan; LIU Xin-yu

    2007-01-01

    The simulation of the upsetting-extruding process of dispersion strengthened copper welding electrode was carried out using Deform-2D finite element analysis software, and the characteristics of metal flow and the effect of different friction factors were analysed. The results show that the whole forming process consists of a forward extrusion and a backward extrusion. When the friction factor of the female die is 0.4, it is advantageous to the forward extrusion forming of the electrode work nose part, while the friction factor of the male die is only 0.1, it would be benefit to the backward extrusion forming of the electrode fit-up hole part. Addition of a scoop channel with 1.5 mm in depth and 4 mm in diameter at the bottom of the female die can avoid folds at the work nose. The rise in temperature is about 60 ℃ during the forming process.

  15. Test of an extruder feed system on the Tore Supra centrifugal pellet injector

    International Nuclear Information System (INIS)

    A deuterium ice extruder feed system has been developed by ORNL for adaptation to the existing ORNL Centrifugal Pellet Injector installed on Tore Supra. A detailed assessment of this feed system coupled to the centrifugal launcher has been carried out in a dedicated test bed at Cadarache, to complete and understand the first results obtained at ORNL and to improve them. The results presented in this paper are related to the study of the pellet trajectory from the deuterium ice cutting to the collection of the accelerated pellets in a guide tube. The overall reliability of the injector has been shown to be very sensitive to deviations in the free flight part of the trajectory, before capture by the rotating launcher

  16. New class of additives to inhibit tree growth in solid extruded cable insulation

    Energy Technology Data Exchange (ETDEWEB)

    Devins, J C; Rzad, S J; Reed, C W; Bartosh, D K; Stines, T W

    1976-03-01

    There is now substantial evidence that in many dielectric failures of solid polyolefinic and other polymeric materials the final disruption may be preceded by the long-time progressive development of a three-dimensional pattern of irregular, sometimes (though not always) carbonized hollow channels diverging from a central stem, and that the ultimate failure follows one of these channels. These minute channels are referred to as ''trees'' and the phenomenon as ''treeing.'' Research conducted from May to Sept. 1975 on techniques for evaluating tree growth and on the development of additives to inhibit tree growth in solid extruded polymeric insulation for electric cables is reported. (LCL)

  17. Development of an improved extruded dielectric cable rated 230 kV

    Energy Technology Data Exchange (ETDEWEB)

    Blais, L D; Traut, R T; Bolden, G N

    1977-05-01

    Work performed on developing an improved 230 kV extruded solid dielectric cable, the techniques of jointing such cables and the testing of terminations suitable for operation at that voltage level are described. Difficulties were encountered during manufacture in applying the semi-conducting extruded conductor shield. A new higher melt point compound solved the problem. A joint capable of operating at the 230 kV level was developed but showed a deficiency under voltage impulse testing while the conductor was at elevated temperature. A reduction in contract scope terminated this effort. Two terminals rated for 230 kV were found to be commercially available from domestic manufacturers. The limited testing performed showed them to be compatible with the cable cross-linked polyethylene insulation and electrically sound under 60 Hertz testing. No direct voltage or impulse voltage testing was performed on the terminations. A sample circuit, consisting of cable and joint, was subjected to impulse voltages at both room temperature and normal conductor operating temperature of 90/sup 0/C. While the cable only was able to withstand voltage impulses in excess of the Basic Impulse Level (BIL) at room temperature, it failed at BIL while conductor was heated to 90/sup 0/C. In like manner, a cable and joint circuit was assembled. Similar voltages were impressed at room temperature without incident. The joint failed at 90/sup 0/C conductor temperature. Cable, joint and termination were assembled in a simulated circuit and subjected to conductor loading to elevate temperature while 60 Hz voltages in excess of normal operating levels were continuously applied.

  18. Hot deformation in nanocrystalline Nd-Fe-B backward extruded rings

    Institute of Scientific and Technical Information of China (English)

    Li An-Hua; Zhao Rui; Lai Bin; Wang Hui-Jie; Zhu Ming-Gang; Li Wei

    2011-01-01

    Radially oriented Nd-Fe-B rings are prepared by backward extrusion of fine grained melt-spun powder.Meltspun powder with the nominal composition of Nd30.sFebal.Co6.0Ga0.6Al0.2B0.9 (wt%) is used as starting material.The effects of process variables,such as deformation temperature (Td),strain rate (ε) and height reduction (Ah%),on the magnetic properties of the rings are investigated.A scanning electron microscope (SEM) equipped with an energy spectrum device is used to study the metallograph and microfracture of the extruded rings.The Br and (BH)max reach the optimum values at Td =800 ℃,ε =0.01 mm/s,and Ah% =70%.It is found by SEM observations that the particle boundaries,which seemingly correspond to the interfaces of the starting melt-spun powders,emerge after the corrosion of metallography specimens.This is helpful for studying the effects of powder-powder interface on the local deformation and deformation homogeneity in the rings.For different spatial positions of the extruded rings,there are characteristic metallographies and microfractures.The upper end of the rings has the least deformation and worst texture,and therefore the worst magnetic properties.The magnetic properties in the radial direction increase slightly along the axis from the bottom to the middle,then steeply decrease at the upper end of the ring.The deformation and the formation-of-texturing processes are discussed.The deformation and the texturing formation of melt-spun Nd-Fe-B alloys probably involve grain boundary sliding and grain rotation,the solution-precipitation process and preferential growth of Nd2Fe14B nanograins along the easy growth a-axis.

  19. Co-extruded solid solutions as immediate release fixed-dose combinations.

    Science.gov (United States)

    Dierickx, L; Van Snick, B; Monteyne, T; De Beer, T; Remon, J P; Vervaet, C

    2014-10-01

    The aim of this study was to develop by means of co-extrusion a multilayer fixed-dose combination solid dosage form for oral application characterized by immediate release for both layers, the layers containing different drugs with different water-solubility. In this study polymers were selected which can be combined in a co-extruded dosage form. Several polymers were screened on the basis of their processability via hot-melt extrusion, macroscopic properties, acetylsalicylic acid (ASA) decomposition and in vitro drug release. ASA and fenofibrate (FF) were incorporated as hydrophilic and hydrophobic model drugs, respectively. Based on the polymer screening experiments Kollidon® PF 12 and Kollidon® VA 64 were identified as useful ASA carriers (core), while Soluplus®, Kollidon® VA 64 and Kollidon® 30 were applicable as FF carriers (coat). The combination of Kollidon® 30 (coat) with Kollidon® PF 12 or Kollidon® VA 64 (core) failed in terms of processability via co-extrusion. All other combinations (containing 20% ASA in the core and 20% FF in the coat) were successfully co-extruded (diameter core: 2mm/thickness coat: 1mm). All formulations showed good adhesion between core and coat. ASA release from the core was complete within 15-30 min (Kollidon® PF 12) or 30-60 min (Kollidon® VA 64), while FF release was complete within 20-30 min (Kollidon® VA 64) or 60 min (Soluplus®). Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) revealed that both drugs were molecularly dispersed in the carriers. Raman mapping exposed very little intermigration of both drugs at the interface. Fixed-dose combinations with good in vitro performance were successfully developed by means of co-extrusion, both layers providing immediate release. PMID:25008213

  20. Oxygen-reducing catalyst layer

    Science.gov (United States)

    O'Brien, Dennis P.; Schmoeckel, Alison K.; Vernstrom, George D.; Atanasoski, Radoslav; Wood, Thomas E.; Yang, Ruizhi; Easton, E. Bradley; Dahn, Jeffrey R.; O'Neill, David G.

    2011-03-22

    An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

  1. Development of GREET Catalyst Module

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhichao [Argonne National Lab. (ANL), Argonne, IL (United States); Benavides, Pahola T. [Argonne National Lab. (ANL), Argonne, IL (United States); Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States); Cronauer, Donald C. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    In this report, we develop energy and material flows for the production of five different catalysts (tar reforming, alcohol synthesis, Zeolite Socony Mobil-5 [ZSM-5], Mo/Co/ γ-Al2O3, and Pt/ γ-Al2O3) and two chemicals (olivine, dimethyl ether of polyethylene glycol [DEPG]). These compounds and catalysts are now included in the Greenhouse Gases, Regulated Emissions and Energy Use in Transportation (GREET™) catalyst module.

  2. Privileged chiral ligands and catalysts

    CERN Document Server

    Zhou, Qi-Lin

    2011-01-01

    This ultimate ""must have"" and long awaited reference for every chemist working in the field of asymmetric catalysis starts with the core structure of the catalysts, explaining why a certain ligand or catalyst is so successful. It describes in detail the history, the basic structural characteristics, and the applications of these ""privileged catalysts"". A novel concept that gives readers a much deeper insight into the topic.

  3. Use of paprika oily extract as pre-extrusion colouring of rice extrudates: impact of processing and storage on colour stability.

    Science.gov (United States)

    Gat, Yogesh; Ananthanarayan, Laxmi

    2016-06-01

    Suitability of paprika oily extract as a pre-extrusion colouring of rice extrudate was evaluated as a function of extrusion parameters viz. moisture content, screw speed and die temperature. Most acceptable coloured rice extrudates in terms of colour and overall acceptability was achieved with addition of 3 % paprika oily extract and which is extruded at fixed conditions of 25 % feed moisture, 120 °C barrel temperature and 100 rpm screw speed. During extrusion, retention of red colour of paprika oily extract added rice extrudates increased with an increase in feed moisture and screw speed while decreased with an increase in barrel temperature. Present study was also undertaken to check effect of addition of butylated hydroxytoluene (BHT) on colour stability of coloured rice extrudates. Coloured rice extrudates were packed in polyethylene, metallised polyethylene and vacuum packaging material and subjected to storage studies for 90 days at 25 and 50 °C with 65 % relative humidity conditions. Retention of red colour (a*) of paprika oily extract added rice extrudates follows first order kinetics, showing a faster rate of degradation with half-life of 48 days when packed in metalized polyethylene and stored at higher temperature conditions. PMID:27478245

  4. Hydrodewaxing with mixed zeolite catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Chester, A.W.; McHale, W.D.; Yen, J.H.

    1986-03-11

    A process is described for catalytically dewaxing a hydrocarbon lubricating oil feedstock comprising contacting the feedstock with a dewaxing catalyst, the dewaxing catalyst comprising, in combination: (a) a zeolite catalyst having a Constraint Index not less than 1, (b) an acidic catalytic material selected from the group consisting of Mordenite, TEA Mordenite, Dealuminized Y, Ultrastable Y, Rare Earth Y, amorphous silica-alumina chlorinated alumina, ZSM-4 and ZSM-20, and (c) a hydrogenation component, and recovering a dewaxed product. A process is also described for catalytically dewaxing a hydrocarbon lubricating oil feedstock comprising contacting the feedstock with a dewaxing catalyst, the dewaxing catalyst comprising, in combinations: (a) a first zeolite catalyst selected from the group consisting of ZSM-5, ZMS-11, ZSM-12, ZSM-22, ZSM-23, ZSM-34, ZSM-35, ZSM-38, ZSM-48, TMA Offretite and Erionite, (b) a second catalyst selected from the group consisting of ZSM-12, ZSM-22, ZSM-38 and ZSM-48, the second zeolite catalyst being different from the first zeolite catalyst, and (c) a hydrogenation component, and recovering a dewaxed product.

  5. The physical ageing mechanism in glassy polycarbonate studied by positron annihilation lifetime spectroscopy

    International Nuclear Information System (INIS)

    Positron annihilation lifetime spectroscopy (PALS) is used to compare the free volume behaviour in as-extruded and aged polycarbonate. The lifetime and intensity of the orthoPositronium pickoff annihilation component are interpreted to represent mean free volume cavity size and free volume concentration, respectively. The PALS results indicate a lower mean free volume cavity size and quasi-equilibrium free volume concentration in the aged material than in the as-extruded polycarbonate. The physical ageing mechanism is discussed in terms of PALS studies and related studies of physical ageing by other researchers investigating secondary relaxations, local ordering phenomena and partial de-ageing phenomena in glassy polymers. A phenomenological description of the mechanism for physical ageing is developed based on the PALS results and literature survey. 74 refs., 2 tabs., 4 figs

  6. Substituição de milho por sorgo triturado ou extrusado em dietas para eqüinos Replacement of corn by ground or extruded sorghum in diets for horses

    Directory of Open Access Journals (Sweden)

    Alexandre Augusto de Oliveira Gobesso

    2008-11-01

    Full Text Available Avaliou-se a substituição de milho triturado ou extrusado por sorgo triturado ou extrusado no concentrado utilizado em dietas para eqüinos. Utilizaram-se quatro éguas com peso médio de 450 kg e 24 meses de idade, sem raça definida, em um delineamento experimental quadrado latino 4 × 4, em esquema fatorial. Avaliaram-se a digestibilidade aparente total da dieta e dos nutrientes e o perfil metabólico dos animais considerando os valores plasmáticos de glicose e insulina pós-ingestão das dietas. As dietas contendo milho e sorgo extrusado proporcionaram coeficientes de digestibilidade total da matéria seca (MS, matéria orgânica (MO, proteína bruta (PB, fibra em detergente neutro (FDN e fibra em detergente ácido (FDA maiores que os obtidos com dietas contendo estes ingredientes triturados. Os coeficientes de digestibilidade aparente total do amido foram semelhantes entre as dietas. A resposta glicêmica e insulinêmica foi maior quando fornecidas as dietas extrusadas, logo, o processamento provocou alterações no metabolismo dos eqüinos. A total substituição do milho pelo sorgo em dietas para eqüinos é possível, uma vez que os coeficientes de digestibilidade dos nutrientes e os níveis plasmáticos de glicose e insulina não diferiram entre as formas de processamento do sorgo testadas. A forma de processamento do milho e do sorgo por extrusão aumenta os coeficientes de digestibilidade do amido e melhora o potencial energético da dieta.The aim of this work was to evaluate, the replacement of ground or extruded corn by sorghum ground or extruded in the concentrate used in diets for equines. Four mares with an average weight of 450 kg and 24 months of age, non-defined breed were distributed to a 4 × 4 Latin square experimental design in a 2 × 2 factorial arrangement (ingredient - corn and sorghum × processing form - ground and extruded. Apparent digestibility of total diet and nutrients were evaluated, and also the metabolic

  7. DEHYDROGENATION CATALYST FOR PRODUCTION OF MTBE

    Science.gov (United States)

    The objectives of this project were to better understand the effect of different catalyst preparation parameters, the effect of different catalyst treatment parameters, and the mechanism of deactivation. Accordingly, catalysts were made using various preparation methods and with...

  8. Deactivation-resistant catalyst for selective catalyst reduction of NOx

    DEFF Research Database (Denmark)

    2011-01-01

    The present invention relates to a catalyst for selective catalytic reduction of NOx in alkali metal containing flue gas using ammonia as reductant, the catalyst comprising a surface with catalytically active sites, wherein the surface is at least partly coated with a coating comprising at least...

  9. Novel Reforming Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Pfefferle, Lisa D; Haller, Gary L

    2012-10-16

    Aqueous phase reforming is useful for processing oxygenated hydrocarbons to hydrogen and other more useful products. Current processing is hampered by the fact that oxide based catalysts are not stable under high temperature hydrothermal conditions. Silica in the form of structured MCM-41 is thermally a more stable support for Co and Ni than conventional high surface area amorphous silica but hydrothermal stability is not demonstrated. Carbon nanotube supports, in contrast, are highly stable under hydrothermal reaction conditions. In this project we show that carbon nanotubes are stable high activity/selectivity supports for the conversion of ethylene glycol to hydrogen.

  10. In-situ characterization of heterogeneous catalysts

    CERN Document Server

    Rodriguez, Jose A; Chupas, Peter J

    2013-01-01

    Helps researchers develop new catalysts for sustainable fuel and chemical production Reviewing the latest developments in the field, this book explores the in-situ characterization of heterogeneous catalysts, enabling readers to take full advantage of the sophisticated techniques used to study heterogeneous catalysts and reaction mechanisms. In using these techniques, readers can learn to improve the selectivity and the performance of catalysts and how to prepare catalysts as efficiently as possible, with minimum waste. In-situ Characterization of Heterogeneous Catalysts feat

  11. Physicochemical, Phytochemical and Nutrimental Impact of Fortified Cereal Based Extrudate Snacks: Effect of Jackfruit Seed Flour Addition and Extrusion Cooking

    Directory of Open Access Journals (Sweden)

    Yogesh Gat

    2015-05-01

    Full Text Available Aim of present study was to estimate quantitative changes in nutrimental, physicochemical and phytochemical properties of rice-jackfruit seed flour blend extrudates. Rice-jackfruit seed flour blend was prepared at 70:30 proportions and was subjected to extrusion cooking. Effect of barrel temperature (140-180°C and screw speed (100-300 rpm on nutrimental, physicochemical (expansion, density, WSI, WAI and hardness and phytochemical (TPC and TFC properties were studied. Rice flour extrudate was found to have 6.63% protein and 0.17% fiber which were further increased to about 8.44 and 0.8%, respectively after addition of jackfruit seed flour at 180°C with 300 rpm. Extrusion cooking at lower barrel temperature resulted in increase in TPC and TFC. Rice-jackfruit seed flour blend extrudate at 180°C with 100 rpm resulted in highest antioxidant capacity and reducing power (208.56 µmol of TE/g and 0.26 mg of AAE/g of dry powder respectively. Practical applications: Although there is increased use of extrusion processing, but still there is no fully developed theory to predict the effects of process variables on various raw materials and their mixtures. Any change in feed composition and process variables can influence extrusion performance as well as product quality. Therefore, it is crucial to study the effect of extrusion process parameters (barrel temperature and screw speed on extrudate characteristics. Also, the researchers, so far, tried lots of combinations for nutraceutical enrichment of extrudate snacks. To the best of our knowledge, this is first report on extrusion cooking of RF fortified with JFSF. In future, this data could be useful for food processing industries. Originality of this study demonstrates the feasibility of developing value added extrudates with improved nutrimental and nutraceutical appeal. Present study shows potential for utilization of jackfruit seed which is part of the waste generated in large quantities when the

  12. Intermediate Ethanol Blends Catalyst Durability Program

    Energy Technology Data Exchange (ETDEWEB)

    West, Brian H; Sluder, Scott; Knoll, Keith; Orban, John; Feng, Jingyu

    2012-02-01

    In the summer of 2007, the U.S. Department of Energy (DOE) initiated a test program to evaluate the potential impacts of intermediate ethanol blends (also known as mid-level blends) on legacy vehicles and other engines. The purpose of the test program was to develop information important to assessing the viability of using intermediate blends as a contributor to meeting national goals for the use of renewable fuels. Through a wide range of experimental activities, DOE is evaluating the effects of E15 and E20 - gasoline blended with 15% and 20% ethanol - on tailpipe and evaporative emissions, catalyst and engine durability, vehicle driveability, engine operability, and vehicle and engine materials. This report provides the results of the catalyst durability study, a substantial part of the overall test program. Results from additional projects will be reported separately. The principal purpose of the catalyst durability study was to investigate the effects of adding up to 20% ethanol to gasoline on the durability of catalysts and other aspects of the emissions control systems of vehicles. Section 1 provides further information about the purpose and context of the study. Section 2 describes the experimental approach for the test program, including vehicle selection, aging and emissions test cycle, fuel selection, and data handling and analysis. Section 3 summarizes the effects of the ethanol blends on emissions and fuel economy of the test vehicles. Section 4 summarizes notable unscheduled maintenance and testing issues experienced during the program. The appendixes provide additional detail about the statistical models used in the analysis, detailed statistical analyses, and detailed vehicle specifications.

  13. Startup procedure for reforming catalysts

    Energy Technology Data Exchange (ETDEWEB)

    McHale, W.D.; Schoennagel, H.J.

    1984-08-14

    Process for reforming a hydrocarbon charge under reforming conditions in a reforming zone containing a sulfur-sensitive metal containing reforming catalyst wherein over-cracking of the charge stock and excessive temperature rise in the reforming zone is suppressed by pre-conditioning the catalyst, prior to contact with the charge, with a reformate of specified octane number and aromatics content.

  14. Doped palladium containing oxidation catalysts

    Science.gov (United States)

    Mohajeri, Nahid

    2014-02-18

    A supported oxidation catalyst includes a support having a metal oxide or metal salt, and mixed metal particles thereon. The mixed metal particles include first particles including a palladium compound, and second particles including a precious metal group (PMG) metal or PMG metal compound, wherein the PMG metal is not palladium. The oxidation catalyst may also be used as a gas sensor.

  15. Catalysts for low temperature oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Toops, Todd J.; Parks, III, James E.; Bauer, John C.

    2016-03-01

    The invention provides a composite catalyst containing a first component and a second component. The first component contains nanosized gold particles. The second component contains nanosized platinum group metals. The composite catalyst is useful for catalyzing the oxidation of carbon monoxide, hydrocarbons, oxides of nitrogen, and other pollutants at low temperatures.

  16. Catalyst design for biorefining.

    Science.gov (United States)

    Wilson, Karen; Lee, Adam F

    2016-02-28

    The quest for sustainable resources to meet the demands of a rapidly rising global population while mitigating the risks of rising CO2 emissions and associated climate change, represents a grand challenge for humanity. Biomass offers the most readily implemented and low-cost solution for sustainable transportation fuels, and the only non-petroleum route to organic molecules for the manufacture of bulk, fine and speciality chemicals and polymers. To be considered truly sustainable, biomass must be derived from resources which do not compete with agricultural land use for food production, or compromise the environment (e.g. via deforestation). Potential feedstocks include waste lignocellulosic or oil-based materials derived from plant or aquatic sources, with the so-called biorefinery concept offering the co-production of biofuels, platform chemicals and energy; analogous to today's petroleum refineries which deliver both high-volume/low-value (e.g. fuels and commodity chemicals) and low-volume/high-value (e.g. fine/speciality chemicals) products, thereby maximizing biomass valorization. This article addresses the challenges to catalytic biomass processing and highlights recent successes in the rational design of heterogeneous catalysts facilitated by advances in nanotechnology and the synthesis of templated porous materials, as well as the use of tailored catalyst surfaces to generate bifunctional solid acid/base materials or tune hydrophobicity. PMID:26755755

  17. Latent catalyst; Senzaisei shokubai

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Epoxy resin, an important function material to support such main industries as electric and electronic devices, automobiles, civil engineering, and building construction, is demanded of development of single liquid type resin having excellent quick hardening performance and storage stability. This requirement comes from environmental problems with an intention of saving energies and reducing resin wastes. The Company, using freely its independent phase separation technology that controls molecular structure of catalysts, developed a latent catalyst having excellent storage stability and high-temperature quick hardening performance. Its major features may be summarized as follows: (1) excellent storage stability at room temperature keeping the product stable for 2.5 months or longer (2 days in conventional products); (2) quick hardening performance hardening the resin in seven seconds at 150 degrees C (equivalent to conventional products); and (3) excellent insulation performance of hardened resin at 140 degrees C of 7 times 10 {sup 13} (ohm) (center dot) cm (2 times 10 {sup 12} (ohm) (center dot) cm in conventional products) (translated by NEDO)

  18. An evaluation of the effects of PEO/PEG molecular weights on extruded alumina rods

    Science.gov (United States)

    Bolger, Nancy Beth

    1998-12-01

    Alumina rods were piston extruded from bodies containing polyethylene glycols (PEGs) and polyethylene oxides (PEOs) with molecular weights ranging from 1,300 to 3,800,000 g/mol. A blend of aluminas possessing different particle size distributions was evaluated with regard to its extrusion pressure by varying the amount of PEG/PEO addition. Behavior exhibited by the alumina blend was dependent upon the additive that was used. The higher molecular weight binders with average molecular weight of 200,000 g/mol and 3,350,000 g/mol displayed the most severe behaviors of near dilatant and dilatant respectively. Physical properties of the green and fired states, as well as the binder burnout, were investigated with the changing additions. Correlation between the green and fired strengths and the changing molecular weights were examined. The additive present influenced the surface properties of the rods, which affected the green strengths. The highest average molecular weight polyethylene glycols showed higher green strengths, while the lowest green strengths were observed for the high molecular weight polyethylene oxides. Fired strengths generally ranged from approximately 12,000 psi to 16,000 psi for additive batches. Alumina pellets containing twelve separate combinations of polyethylene glycol with polyethylene oxide were dry pressed. Physical properties of the green and fired states were examined. Statistical analysis was performed upon the data and seven combinations of polyethylene glycol with polyethylene oxide were deemed significant. These combinations in conjunction with the same alumina blend were then piston extruded. The addition of polyethylene glycol reduced the near dilatant behavior exhibited by the 200,000 g/mol average molecular weight polyethylene oxide. Dilatant behavior was completely eliminated from the 3,350,000 g/mol average molecular weight polyethylene oxide batches. Physical properties of the green and fired states were again investigated with

  19. Extruded soybean meal increased feed intake and milk production in dairy cows.

    Science.gov (United States)

    Giallongo, F; Oh, J; Frederick, T; Isenberg, B; Kniffen, D M; Fabin, R A; Hristov, A N

    2015-09-01

    The objective of this study was to assess the effects of 2 extruded soybean meals (ESBM) processed at 2 extruder temperatures, 149°C (LTM) and 171°C (HTM), on performance, nutrient digestibility, milk fatty acid and plasma amino acid profiles, and rumen fermentation in lactating dairy cows. Nine multiparous Holstein cows were included in a replicated 3×3 Latin square design experiment with three 28-d periods. The control diet contained 13% solvent-extracted soybean meal (SSBM; 53.5% crude protein with 74.1% ruminal degradability and 1.8% fat), which was replaced with equivalent amount (dry matter basis) of LTM (46.8%, 59.8%, and 10.0%) or HTM (46.9%, 41.1%, and 10.9%, respectively) ESBM in the 2 experimental diets (LTM and HTM, respectively). The diets met or exceeded the nutrient requirements of the cows for net energy of lactation and metabolizable protein. The 2 ESBM diets increased dry matter intake and milk yield compared with SSBM. Feed efficiency and milk composition were not affected by treatment. Milk protein yield tended to be increased by ESBM compared with SSBM. Milk urea N and urinary urea N excretions were increased by the ESBM diets compared with SSBM. Concentration of fatty acids with chain length of up to C17 and total saturated fatty acids in milk fat were generally decreased and that of C18 and total mono- and polyunsaturated fatty acids was increased by the ESBM diets compared with SSBM. Blood plasma concentrations of His, Leu, and Val were increased by HTM compared with LTM and SSBM. Plasma concentration of Met was decreased, whereas that of carnosine was increased by the ESBM diets. Treatments had no effect on rumen fermentation, but the proportion of Fibrobacter spp. in whole ruminal contents was increased by HTM compared with SSBM and LTM. Overall, data from this crossover experiment suggest that substituting SSBM with ESBM in the diet has a positive effect on feed intake and milk yield in dairy cows. PMID:26188569

  20. Accelerated deployment of nanostructured hydrotreating catalysts. Final CRADA Report.

    Energy Technology Data Exchange (ETDEWEB)

    Libera, J.A.; Snyder, S.W.; Mane, A.; Elam, J.W.; Cronauer, D.C.; Muntean, J.A.; Wu, T.; Miller, J.T. (Chemical Sciences and Engineering Division); ( ES)

    2012-08-27

    Nanomanufacturing offers an opportunity to create domestic jobs and facilitate economic growth. In response to this need, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy issued a Research Call to develop nanomanufacturing capabilities at the National Laboratories. High performance catalysts represent a unique opportunity to deploy nanomanufacturing technologies. Re-refining of used lube oil offers an opportunity to create manufacturing jobs and decrease dependence on imported petroleum. Improved catalysts are required to produce a better quality product, decrease environmental impact, extend catalyst life, and improve overall economics of lube oil re-refining. Argonne National Laboratory (Argonne) in cooperation with Universal Lubricants, Inc. (ULI) and Chemical Engineering Partners (CEP) have carried out a Cooperative Research and Development Agreement (CRADA) to prepare nanostructured hydrotreating catalysts using atomic layer deposition (ALD) to exhibit superior performance for the re-refining of used lube oil. We investigated the upgrading of recycled lube oil by hydrogenation using commercial, synthetically-modified commercial catalysts, and synthesized catalysts. A down-flow (trickle bed) catalytic unit was used for the hydrogenation experiments. In addition to carrying out elemental analyses of the various feed and product fractions, characterization was undertaken using H{sup 1} and C{sup 13} NMR. Initially commercial were evaluated. Second these commercial catalysts were promoted with precious metals using atomic layer deposition (ALD). Performance improvements were observed that declined with catalyst aging. An alternate approach was undertaken to deeply upgrade ULI product oils. Using a synthesized catalyst, much lower hydrogenation temperatures were required than commercial catalysts. Other performance improvements were also observed. The resulting lube oil fractions were of high purity even at low reaction severity. The

  1. Supported molten-metal catalysts

    Science.gov (United States)

    Datta, Ravindra; Singh, Ajeet; Halasz, Istvan; Serban, Manuela

    2001-01-01

    An entirely new class of catalysts called supported molten-metal catalysts, SMMC, which can replace some of the existing precious metal catalysts used in the production of fuels, commodity chemicals, and fine chemicals, as well as in combating pollution. SMMC are based on supporting ultra-thin films or micro-droplets of the relatively low-melting (<600.degree. C.), inexpensive, and abundant metals and semimetals from groups 1, 12, 13, 14, 15 and 16, of the periodic table, or their alloys and intermetallic compounds, on porous refractory supports, much like supported microcrystallites of the traditional solid metal catalysts. It thus provides orders of magnitude higher surface area than is obtainable in conventional reactors containing molten metals in pool form and also avoids corrosion. These have so far been the chief stumbling blocks in the application of molten metal catalysts.

  2. Process studies, engineering feasibility and cost analysis for starch encapsulating of herbicides on the co-rotating twin screw extruder

    International Nuclear Information System (INIS)

    The co-rotating, fully intermeshing twin screw extruder (ZSK) has been applied to the continuous compounding of starch encapsulated herbicide formulations. The ZSK is well recognized in the plastics, food and feed industries as a versatile mixer/reactor for the most difficult continuous processing requirements. Over the last five years, the continuous extrusion process for compounding bioactive agents into starch matrices has been developed. The continuous process of herbicide encapsulation includes the gelatinization of unmodified cornstarch in the extruder followed by the addition and incorporation of one or more active herbicides. The physical form of the herbicides ranges form oily liquid to powder solid. This report will summarize the results of our process studies. Using our understanding of the various process interactions, a cost analysis will be presented for a scaled up commercial operation. (author). 5 refs, 5 figs, 5 tabs

  3. In situ quantitation of the index of mixing in a single-screw extruder by magnetic resonance imaging

    Science.gov (United States)

    Amin, M. H. G.; Hall, L. D.; Wang, W.; Ablett, S.

    2004-09-01

    Magnetic resonance imaging (MRI) has been used to quantitate in situ the goodness of laminar mixing of two streams of 1% aqueous sodium carboxymethylcellulose with different MnCl2 concentrations, flowing through a single-screw extruder (0.04 m diameter, length to diameter ratio of 4.575). Two-dimensional MR images (0.0002 × 0.0002 × 0.003 m3 resolution) were acquired using gradient echo MRI protocols which had been calibrated to map MnCl2 concentrations. The resultant distributions were then used to calculate indices of mixing (normalized variances of concentration) in the part of the extruder under study. The smallest index (0.34) was measured near the outlet at the faster speed (30 rpm) and slower flow rate (47 ml min-1); and the largest index (0.73) was near the inlet for 20 rpm and 76 ml min-1.

  4. Discrete element simulations and validation tests investigating solids-conveying processes with pressure buildup in single screw extruders

    Science.gov (United States)

    Lessmann, Johann-Sebastian; Schoeppner, Volker

    2016-03-01

    The goal of this contribution is to describe a method of simulating solids-conveying processes in single screw extruders which include a defined back pressure leading to a resulting pressure buildup in the screw channel. To do so, use is made of the Discrete Element Method. Material parameters are presented, as well as details concerning the contact model used and the simulation tool EDEM. Additionally, a test setup is presented which has been used to validate the solids-conveying simulations. Results are shown for both simulations and experimental tests. Comparing the results from simulations and measurements shows acceptable conformity. Such simulations and experimental tests are crucial in order to better understand the buildup of pressure in high-speed single-screw extruders.

  5. Solid state polymerization of pet/pc extruded blend: effect of reaction temperature on thermal, morphological and viscosity properties

    OpenAIRE

    Luis Claudio Mendes; Isaac Albert Mallet; Sibele Piedade Cestari; Frederico Gonçalves de Albuquerque Dias; Patricia Soares da Costa Pereira

    2014-01-01

    A systematic study of solid state polymerization (SSP), concerning the melt extruded blend of poly(ethylene terephthalate)/polycarbonate (catalyzed PET/PC, 80/20 wt %), as a function of temperature range (180-190°C) for a fixed time (6 h) is presented. The materials obtained were evaluated by differential scanning calorimetry (DSC), thermogravimetry/derivative thermogravimetry (TG/DTG), optical microscopy (OM) and intrinsic viscosity (IV) analysis. After SSP, at all reaction temperatures, PET...

  6. AROMATIC CHARACTERISTICS OF PECORINO CHEESES OBTAINED FROM MILK OF EWES FED DIETS CONTAINING DIFFERENT EXTRUDED LINSEED CONCENTRATIONS

    Directory of Open Access Journals (Sweden)

    R. Branciari

    2009-09-01

    Full Text Available The aim of the present study is to investigate the flavour characteristics of ewe cheeses made with two different techniques (cheeses obtained from raw milk or from thermized milk with adjunct starter cultures and using milk from animals fed diets with different concentrations of extruded linseed. Aromatic differences linked to the linseed concentrations in the diets were found for the raw milk cheeses, while no such differences were found in the cheeses made from thermized milk with adjunct starter cultures.

  7. Effect of incorporation of corn byproducts on quality of baked and extruded products from wheat flour and semolina

    OpenAIRE

    Sharma, Savita; Gupta, Jatinder Pal; Nagi, H. P. S.; Kumar, Rakesh

    2011-01-01

    The effect of blending level (0, 5, 10, 15 and 20%) of corn bran, defatted germ and gluten with wheat flour on the physico-chemical properties (protein, crude fiber, phosphorus, iron and calcium), baking properties of bread, muffins and cookies, and extrusion properties of noodles and extruded snacks prepared from semolina were examined. Blending of wheat flour and corn byproducts significantly increased the protein, crude fiber, phosphorus, iron and calcium contents. Breads from gluten blend...

  8. Peningkatan Efektivitas Mesin Extruder Matador EX 920 Dengan Metode Overall Equipment Effectiveness (OEE) Di PT. Central Proteina Prima Tbk

    OpenAIRE

    Sianturi, Jost Irianto

    2011-01-01

    PT. Central Proteina Prima Tbk merupakan perusahaan yang bergerak dalam pengolahan pakan ternak ikan, yang tidak terlepas dari masalah yang berhubungan dengan efektivitas mesin/peralatan yang diakibatkan oleh six big losses. Pada mesin Extruder Matador ini masalah yang sering terjadi adalah menurunnya kemampuan kerja dari mesin diakibatkan oleh terjadinya kegosongan pakan yang menjadi kerak-kerak pada permukaan plat-plat sehingga mengakibatkan menurunnya efisiensi kerja mesi...

  9. Physical characteristics of extruded cassava starch Características físicas de amido de mandioca extrusado

    OpenAIRE

    Magali Leonel; Taila Santos de Freitas; Martha Maria Mischan

    2009-01-01

    Considering the importance of cassava starch for Brazilian industries, the current work aimed at evaluating the effects of extrusion parameters on the physical characteristics, mainly viscosity properties of extruded cassava starch. A factorial central composite design (2³) with three independent variables and the response surface methodology were used to evaluate the results of expansion index, specific volume, water absorption index, water solubility index, color and paste properties, accor...

  10. Nutritional value of raw soybeans, extruded soybeans, roasted soybeans and tallow as fat sources in early lactating dairy cows

    Directory of Open Access Journals (Sweden)

    A. Moosavi

    2012-09-01

    Full Text Available Thirty multiparous Holstein cows (29.8 ± 4.01days in milk; 671.6 ± 31.47 kg of body weight were used in a completely randomized design to compare nutritional value of four fat sources including tallow, raw soybeans, extruded soybeans and roasted soybeans for 8 weeks. Experimental diets were a control containing 27.4 % alfalfa silage, 22.5% corn silage, and 50.1% concentrate, and four diets with either tallow, raw soybean, extruded soybean, or roasted soybean added to provide 1.93% supplemental fat. Dry matter and NEL intakes were similar among treatments, while cows fed fat diets had significantly (P<0.05 high NEL intakes when compared to control with no fat. Supplemental fat, whether tallow or full fat soybeans increased milk production (1.89-2.45 kg/d; P<0.01 and FCM production (1.05-2.79; P<0.01. Milk fat yield and percentage of cows fed fat-supplemented diets were significantly (P<0.01 and P<0.05 respectively higher than control. Between fat-supplemented diets, roasted soybean caused highest milk fat yield and extruded soybean caused lowest milk fat yield. There was no significant effect of supplemental fat on the milk protein and lactose content and yield. Feed efficiency of fat-supplemented diets was significantly (P<0.01 higher than control. Body weight, body weight change and BCS (body condition score of cows, as well as energy balance and energy efficiency were similar between treatments. In conclusion, while there was no significant effect of fat sources on production response of cows, fat originating from heat-treated soybean help to minimize imported RUP (rumen undegradable protein sources level as fish meal in comparison with tallow and raw soybean oil. In the Current study, there was no statistical significance among nutritional values of oil from extruded soybeans and roasted soybeans.

  11. Physicochemical properties and mechanisms of drug release from melt-extruded granules consisting of chlorpheniramine maleate and Eudragit FS.

    Science.gov (United States)

    Zhang, Feng

    2016-01-01

    The objective of this research project was to characterize the drug release profiles, physicochemical properties and drug-polymer interaction of melt-extruded granules consisting of chlorpheniramine maleate (CPM) and Eudragit® FS. Melt extrusion was performed using a single screw extruder at a processing temperature of 65-75 °C. The melt extrudate was milled, blended with lactose monohydrate and then filled into hard gelatin capsules. Each capsule contained 300 mg CPM granules. The release of CPM was determined with the United States Pharmacopeia dissolution apparatus II using a three-stage dissolution medium testing in order to simulate the pH conditions of the gastrointestinal tract. Pore structure, thermal properties and surface morphologies of CPM granules were studied using mercury and helium pycnometer, differential scanning calorimeter and scanning electron microscope. Sustained release of CPM over 10 h was achieved. The release of CPM was a function of drug loading and the size of the milled granules. The complexation between CPM and Eudragit® FS as the result of counterion condensation was observed, and the interaction was characterized using membrane dialysis and H(1) NMR techniques. In both 0.1 N HCl and phosphate buffer pH 6.8, CPM was released via a diffusion mechanism and the release rate was controlled by the pore structure of the melt-extruded granules. In phosphate buffer pH 7.4, CPM release was controlled by the low pH micro-environment created by CPM, the pore structure of the granules and the in situ complexation between CPM and Eudragit® FS. PMID:26065535

  12. Aqueous extraction of residual oil from sunflower press cake using a twin-screw extruder: Feasibility study

    OpenAIRE

    Evon, Philippe; Vandenbossche, Virginie; Pontalier, Pierre-Yves; Rigal, Luc

    2009-01-01

    The objective of this study was to evaluate the feasibility of an aqueous process to extract the residual oil from sunflower press cakes using a co-rotating twin-screw extruder. Two different configurations were tested: the expression from whole seeds followed by the aqueous extraction, in two successive apparatus or in the same one. For the aqueous extraction stage, the oil yield depended on the operating conditions including screw rotation speed, screw profile, and inlet flow rates of press...

  13. The Comparison of Water Absorption Analysis between Counterrotating and Corotating Twin-Screw Extruders with Different Antioxidants Content in Wood Plastic Composites

    OpenAIRE

    Sahrim Ahmad; Mohd Hafizuddin Ab Ghani

    2011-01-01

    Water absorption is a major concern for natural fibers as reinforcement in wood plastic composites (WPCs). This paper presents a study on the comparison analysis of water absorption between two types of twin-screw extruders, namely, counterrotating and corotating with presence of variable antioxidants content. Composites of mixed fibres between rice husk and saw dust with recycled high-density polyethylene (rHDPE) were prepared with two different extruder machines, namely, counterrotating and...

  14. An investigation into the microstructure/strain pattern relationship in backward extruded AZ91 magnesium alloy

    International Nuclear Information System (INIS)

    Highlights: ► Strain pattern developed during BE is inhomogeneous throughout the cross section. ► Microstructure evolution of AZ91 alloy was studied during BE at high temperatures. ► Heterogeneous microstructure fits well by related strain pattern over the cross section. ► Size and morphology of the γ-eutectic phase have been changed after BE processing. - Abstract: The contours of equivalent plastic strain (EPS) and shear strain (SS) over the cross section of backward extruded AZ91 magnesium alloy have been modeled employing the finite element method (FEM). The results indicate that the distributions of EPS and SS are not homogenous at different regions over the products’ cross section. In addition, the microstructure evolutions and strain pattern relationship have been explored through applying the backward extrusion (BE) method in the temperature range of 250–450 °C. The results indicate that the microstructural features (grain size, mechanical twins and γ-second phases) of different regions are strongly affected by applying backward extrusion, which is fairly consistent with the heterogeneous strain distribution. The obtained results are properly addressed relying on the principal deformation and restoration mechanisms, which operate under specified deformation conditions. The hardness measurements have been also employed to trace the related changes

  15. Development of Extruded Scintillator and Single-Bit Tracking Calorimetry - Final Report

    International Nuclear Information System (INIS)

    The R and D activities funded in part by this grant have been successfully concluded. Some adjust-ments had to be made to the course anticipated in the original proposal. These were necessitated to a large extent by external factors, such as changes in demands for different geometries, and rapid progress in the integration of the silicon-based photodetectors. However, internal factors like improvements in our own understanding the behavior of the extrusion line and that of the extruded scintillator strips also played a role. The table below summarizes some important milestones. These are in accord with the projections in reports submitted in prior years. In the present document we focus on the work done since the last report. We are pleased to report also that the final task on the list in our proposal, namely 'Production and integration of cells for the test-beam module' was a resounding success, albeit with the modified choice of strips operating in analog mode. This solution for the TCMT module was adopted by the CALICE collaboration to meet budgetary constraints since the Si photodetectors remain rather expensive. Planes of trips are packaged into 'cassettes' that slide between absorber plates, as shown in Fig. 2. of the last report and in Ref. (4). Figure 1 below shows the response from individual strips when a plane is scanned across with a 5 GeV electron beam at DESY. Figure 2 shows the TCMT ready to be shipped to CERN. Including the photodetectors, each cassette is 102 cm x 109 cm x 1.5 cm. The first (last) 8 stainless steel absorber planes are 2 cm (10 cm) thick. The strips in alternate layers are oriented perpendicular to each other. Including the support structure, the TCMT measures approximately 1.3 m x 1.3 m x 1.6 m and weighs 20 tons. Beam tests at CERN demonstrated a marked improvement in single-particle energy resolution when the information from the upstream Analog Hadron Calorimeter (AHCAL) is supplemented by that from the TCMT. Both the SiD and

  16. Alcohol dose dumping: The influence of ethanol on hot-melt extruded pellets comprising solid lipids.

    Science.gov (United States)

    Jedinger, N; Schrank, S; Mohr, S; Feichtinger, A; Khinast, J; Roblegg, E

    2015-05-01

    The objective of the present study was to investigate interactions between alcohol and hot-melt extruded pellets and the resulting drug release behavior. The pellets were composed of vegetable calcium stearate as matrix carrier and paracetamol or codeine phosphate as model drugs. Two solid lipids (Compritol® and Precirol®) were incorporated into the matrix to form robust/compact pellets. The drug release characteristics were a strong function of the API solubility, the addition of solid lipids, the dissolution media composition (i.e., alcohol concentration) and correspondingly, the pellet wettability. Pellets comprising paracetamol, which is highly soluble in ethanol, showed alcohol dose dumping regardless of the matrix composition. The wettability increased with increasing ethanol concentrations due to higher paracetamol solubilities yielding increased dissolution rates. For pellets containing codeine phosphate, which has a lower solubility in ethanol than in acidic media, the wettability was a function of the matrix composition. Dose dumping occurred for formulations comprising solid lipids as they showed increased wettabilities with increasing ethanol concentrations. In contrast, pellets comprising calcium stearate as single matrix component showed robustness in alcoholic media due to wettabilities that were not affected by the addition of ethanol. The results clearly indicate that the physico-chemical properties of the drug and the matrix systems are crucial for the design of ethanol-resistant dosage forms. Moreover, hydrophobic calcium stearate can be considered a suitable matrix system that minimizes the risk of ethanol-induced dose dumping for certain API's. PMID:25733499

  17. Parameters affecting enzyme-assisted aqueous extraction of extruded sunflower meal.

    Science.gov (United States)

    Campbell, Kerry A; Vaca-Medina, Guadalupe; Glatz, Charles E; Pontalier, Pierre-Yves

    2016-10-01

    Microscopic observation of sunflower meal before and after extraction indicated that extensive cellular disruption was achieved by extrusion, but that unextracted oil remained sequestered as coalesced oil within the void spaces of disrupted cotyledon cells. A full factorial design experiment was defined to develop aqueous extraction processing (AEP) with and without enzymes to improve vegetable oil extraction yields of extruded sunflower meal. This experimental design studied the influence of four parameters, agitation, liquid/solid (L/S) ratio, and cellulase and protease addition, on extraction yield of lipid and protein. Agitation and addition of cellulases increased oil extraction yield, indicating that emulsification of oil and alteration of the geometry of the confining cellular matrix were important mechanisms for improving yields. Protease and liquid-solid ratio of the extraction mixture did not have significant effects, indicating key differences with previously established soy oil extraction mechanisms. Maximum yields attained for oil and protein extraction were 39% and 90%, respectively, with the aid of a surfactant. PMID:27132846

  18. Pre-conceptual Development and characterization of an extruded graphite composite fuel for the TREAT Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Luther, Erik; Rooyen, Isabella van; Leckie, Rafael; Papin, Pallas; Nelson, Andrew; Hunter, James

    2015-03-01

    In an effort to explore fuel systems that are more robust under accident scenarios, the DOE-NE has identified the need to resume transient testing. The Transient Reactor Test (TREAT) facility has been identified as the preferred option for the resumption of transient testing of nuclear fuel in the United States. In parallel, NNSA’s Global Threat Reduction Initiative (GTRI) Convert program is exploring the needs to replace the existing highly enriched uranium (HEU) core with low enriched uranium (LEU) core. In order to construct a new LEU core, materials and fabrication processes similar to those used in the initial core fabrication must be identified, developed and characterized. In this research, graphite matrix fuel blocks were extruded and materials properties of were measured. Initially the extrusion process followed the historic route; however, the project was expanded to explore methods to increase the graphite content of the fuel blocks and explore modern resins. Materials properties relevant to fuel performance including density, heat capacity and thermal diffusivity were measured. The relationship between process defects and materials properties will be discussed.

  19. Effect of paste humidity on kinetics of carbothermal reduction of extruded barite and coke mixture

    Science.gov (United States)

    Salem, A.; Jamshidi, S.

    2012-08-01

    The effect of the moisture content of barite-coke paste on the kinetics of carbothermal reduction was investigated to understand the role of extrusion technique on this type of solid-gas reaction. The pastes were formulated using the typical natural barite and coke powders normally used in the industrial scale. 0.65 wt.% carboxyl methyl cellulose and different amounts of distilled water, ranging 24.3-34.4% were added to the mixed powders. The obtained pastes were then shaped by a laboratory extruder. The extrusion process was assessed by determining the total porosity of dry samples. The samples in the form of disc were isothermally heated at different temperatures in the range of 800-950 °C and the conversion of barite into barium sulfide was measured by the iodometry. The reduction data were analyzed by a modified kinetic model and the frequency factor and activation energy were calculated to evaluate the reduction mechanism. It was found that the moisture content of the paste significantly affects the active site density due to increasing contact surface area between coke and barite particles.

  20. [Quality of cookies formulated with extruded rice bran in substitution to wheat flour and cassava starch].

    Science.gov (United States)

    Lacerda, Diracy Betânia C L; Soares Soares, Júnior Manoel; Bassinello, Priscila Zaczuk; Santos Siqueira, Beatriz; Koakuzu, Selma Nakamoto

    2009-06-01

    Rice bran is a byproduct resulted from the rice milling process. It corresponds to 8% of the total rice grain. It is an abundant and low-cost product which has high concentration of insoluble fiber, vitamins and minerals, and it is mainly applied for animal feeding and soil fertilizing. The aim of this work was to evaluate the color, the proximate composition and acceptability of the cookies formulated with extruded rice bran (ERB). Completely randomized design was applied using one control and four treatments (12.5%, 25%, 37.5% and 50% of EBR in place of wheat flour and cassava starch). All analyses were performed according to standard methods. The gradual addition of EBR to biscuits influenced its darkening and yellow/red color tendency. Cookies with 50% of ERB had higher contents of protein (7.56 g 100 g(-1)), dietary fiber (5.17 g 100 g(-1)) and ash (3.31 g 100 g(-1)) and lower proportion of carbohydrate (60.78 g 100 g(-1)) than the control. Forty grams of that formulation supplies more than 10% of daily recommended intakes of magnesium, phosphorus and copper. The cookies were well accepted and did not show significant difference (P = 0,05) regarding the appearance, texture and flavor when compared to control. Cookies formulated with 50% of ERB present better nutritional quality than those elaborated without rice bran and have good sensory acceptance. PMID:19719018

  1. Microstructural and mechanical properties analysis of extruded Sn–0.7Cu solder alloy

    Directory of Open Access Journals (Sweden)

    Abdoul-Aziz Bogno

    2015-01-01

    Full Text Available The properties and performance of lead-free solder alloys such as fluidity and wettability are defined by the alloy composition and solidification microstructure. Rapid solidification of metallic alloys is known to result in refined microstructures with reduced microsegregation and improved mechanical properties of the final products as compared to normal castings. The rapidly solidified Sn-based solders by melt spinning were shown to be suitable for soldering with low temperature and short soldering duration. In the present study, rapidly solidified Sn–0.7 wt.%Cu droplets generated by impulse atomization (IA were achieved as well as directional solidification under transient conditions at lower cooling rate. This paper reports on a comparative study of the rapidly solidified and the directionally solidified samples. Different but complementary characterization techniques were used to fully analyze the solidification microstructures of the samples obtained under the two cooling regimes. These include X-ray diffractometry (XRD and scanning electron microscopy (SEM. In order to compare the tensile strength and elongation to fracture of the directionally solidified ingot and strip castings with the atomized droplet, compaction and extrusion of the latter were carried out. It was shown that more balanced and superior tensile mechanical properties are available for the hot extruded samples from compacted as-atomized Sn–0.7 wt.%Cu droplets. Further, elongation-to-fracture was 2–3× higher than that obtained for the directionally solidified samples.

  2. Tensile and Creep Behavior of Extruded AA6063/SiCp Al MMCs

    Science.gov (United States)

    Khalifa, Tarek A.; Mahmoud, Tamer S.

    2010-03-01

    Composites of AA6063 Al alloy reinforced with SiC particles (SiCp) were prepared by the vortex method. Hot extrusion was carried out for the as cast composites with a reduction in area of 25%. Tensile and creep behavior of as-cast and extruded composites were studied at elevated temperatures. Tensile tests carried out at room temperature showed that for the as-cast composites, the addition of SiCp up to 10% by weight improves the strength but reduces ductility. Further addition of SiCp reduces the strength and ductility of the composites. At 150 and 300° C the matrix alloy exhibits higher strength than the composites. Extrusion generally raised the strength of the composites at both room and elevated temperatures. Time rupture creep tests carried out at 300° C showed that the composites exhibit higher creep resistance as compared to the matrix alloy except at relatively low stresses where the matrix has a better creep resistance. Extrusion improved the resistance of composites to creep rupture.

  3. Extruded polymer films pigmented with a heterogeneous ion-pair based lumophore for O2 sensing.

    Science.gov (United States)

    Mills, Andrew; Graham, Ashleigh

    2013-11-01

    A novel approach to polymeric Ru(II)-diimine luminescent O2 sensors is described. The Ru(II)-diimine, tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) dichloride ([Ru(dpp)3](2+)), is first ion-paired to the surface of heterogeneous TiO2 particles, rendered negatively charged due to the alkali nature of the aqueous solution, to produce an O2 sensitive pigment with a strikingly high oxygen sensitivity (i.e. PO2 (S = 1/2) = 0.002 atm, where PO2 (S = 1/2) is defined as the amount of oxygen required to reduce the initial, oxygen free luminescence by 50%), and a rapid response to oxygen. The pigment is extruded in low density polyethylene (LDPE) to produce a thin (60 μm), flexible, O2 sensing plastic film, with an O2 sensitivity (PO2 (S = 1/2) = 0.84 atm) comparable to the more traditional homogeneous lumophore ion-pair based O2 sensor ink films reported in the literature. PMID:24040643

  4. Effect of Frequency on Fatigue Lifetime of Extruded Mg-3%Al-l%Zn Alloy

    Institute of Scientific and Technical Information of China (English)

    ZHU Rong; WU Yanjun; WANG Jingtao; LI Youyan

    2012-01-01

    Samples prepared from as-extruded magnesium alloy Mg-3%Al-l%Zn (AZ31) billets were utilized in low-cycle fatigue tests in order to investigate the frequency-dependent fatigue life.Fully reversed strain-controlled tension-compression fatigue tests were carried out at frequencies of 1 Hz and 10 Hz in air.The microstructures were examined by optical microscopy (OM) and scanning electron microscopy (SEM).When the strain amplitude was lower than 0.2%,the fatigue life exhibited a positive correlation with loading frequency,and the activity of twinning was increased at 10 Hz.When the strain amplitude was higher than 0.2%,significant twinning was observed both at these two frequencies,and the fatigue life was found to be independent of frequency.The possible reasons for this frequency-related fatigue lifetime may be due to the dependence of twinning upon loading frequency and strain amplitude.

  5. Setup of Extruded Cementitious Hollow Tubes as Containing/Releasing Devices in Self-Healing Systems

    Directory of Open Access Journals (Sweden)

    Alessandra Formia

    2015-04-01

    Full Text Available The aim of this research is to produce self-healing cementitious composites based on the use of cylindrical capsules containing a repairing agent. Cementitious hollow tubes (CHT having two different internal diameters (of 2 mm and 7.5 mm were produced by extrusion and used as containers and releasing devices for cement paste/mortar healing agents. Based on the results of preliminary mechanical tests, sodium silicate was selected as the healing agent. The morphological features of several mix designs used to manufacture the extruded hollow tubes, as well as the coatings applied to increase the durability of both core and shell materials are discussed. Three-point bending tests were performed on samples produced with the addition of the above-mentioned cementitious hollow tubes to verify the self-healing effectiveness of the proposed solution. Promising results were achieved, in particular when tubes with a bigger diameter were used. In this case, a substantial strength and stiffness recovery was observed, even in specimens presenting large cracks (>1 mm. The method is inexpensive and simple to scale up; however, further research is needed in view of a final optimization.

  6. Rapid 3D Printing of Multifunctional Calcium Alginate Gel Pipes using Coaxial Jet Extruder

    Science.gov (United States)

    Rykaczewski, Konrad; Damle, Viraj

    2014-11-01

    Calcium alginate (CA) forms when solution containing sodium alginate (SA) comes in contact with a CaCl2 solution. The resulting gel is biocompatible as well as edible and is used in production of bio-scaffolds, artificial plant seeds, and edible substances. In the latter application, referred to in the culinary world as ``spherification,'' flavored liquids are mixed with the SA and dripped into CaCl2 solution to form gel encapsulated flavored ``marbles.'' Previously, crude 3D printing of CA structures has been achieved by stacking of such flavored liquid filled marbles. In turn, solid CA rods have been fabricated by properly mixing flow of the two solutions using a microfluidic device. Here we show that by using two circular cross-section coaxial nozzles to produce coaxial jets of the SA and CaCl2 solutions, liquid filled CA micro-to-mili scale gel pipes can be produced at speeds around ~ 150 mm/s. Such extrusion rate is compatible with most commercially available 3D printers, facilitating adoption of the CA pipe coaxial jet extruder. Here, the impact of inner and outer liquid properties and flow speeds on the gel pipe extrusion process is discussed. KR acknowledges startup funding from ASU.

  7. A model for evaluating the flow rate of an extruder for plastic recycling

    International Nuclear Information System (INIS)

    For several years, Municipal Solid Wastes (MSW) from packaging, newspapers, batteries, furniture, metals, clothing's, bottles, and food scraps have contributed negatively to the increased deterioration of our environments particularly in developing countries. It has resulted in activities that threaten lives (such as disease outbreaks and severe health hazards). As a result, governments and other stakeholders in environment have considered both theoretical and practical approaches to waste control. Recycling, which has enormous benefits of reducing manufacturing cost of new products and providing employment for the populace has been chosen as a viable option. Despite the multi-disciplinary efforts involved recycling models, guidelines applicable in the design of flow rates of extruders for plastic recycling processes are missing. This gap is addressed in the current paper. This paper conceptualizes the flow rates as an input-output system in a continuous dynamic state. With a focus on the melting activity (operation section), the analysis of flow in the metering zone involves an estimation of the quantity of recycled materials that could be produced per time. The work hopefully stimulates research in an area where quantitative methodologies are sparse. (author)

  8. Influence of hard particle addition and chemical interdiffusion on the properties of hot extruded tool steel compounds

    International Nuclear Information System (INIS)

    Low alloyed steel bars were co-extruded with pre-sintered tool steel powders with the addition of tungsten carbides (W2C/WC) as hard particles. During the hot extrusion process of these massive and powdery materials, an extrudate is formed consisting of a completely densified wear resistant coating layer and a bulk steel bar as the tough substrate core. This work combines experimental measurements (EPMA) and diffusion calculations (DICTRATM) to investigate the effect of hard particle addition and its dissolution, as well as the formation of M6C carbides on the properties of two different PM tool steel coatings hot extruded with a 1.2714 steel bar. A carburization effect resulting from the W2C hard particles is responsible for an increase of the 1.2344 steel matrix hardness. The mechanical properties of the interface region between coating matrix and substrate are influenced by chemical interdiffusion of carbon and other alloying elements occurring during heat treatment.

  9. Influence of hard particle addition and chemical interdiffusion on the properties of hot extruded tool steel compounds

    Energy Technology Data Exchange (ETDEWEB)

    Silva, P.A. [Max-Planck-Institut fuer Eisenforschung GmbH, MPIE, Max-Planck-Strasse 1, D-40237 Duesseldorf (Germany); Weber, S., E-mail: weber@wtech.rub.de [Institut fuer Werkstoffe, Ruhr-Universitaet Bochum, Universitaetsstrasse, D-44780 Bochum (Germany); Helmholtz-Zentrum Berlin, Glienicker Strasse 100, D-14109 Berlin (Germany); Inden, G. [Max-Planck-Institut fuer Eisenforschung GmbH, MPIE, Max-Planck-Strasse 1, D-40237 Duesseldorf (Germany); Pyzalla, A.R. [Helmholtz-Zentrum Berlin, Glienicker Strasse 100, D-14109 Berlin (Germany)

    2009-08-15

    Low alloyed steel bars were co-extruded with pre-sintered tool steel powders with the addition of tungsten carbides (W{sub 2}C/WC) as hard particles. During the hot extrusion process of these massive and powdery materials, an extrudate is formed consisting of a completely densified wear resistant coating layer and a bulk steel bar as the tough substrate core. This work combines experimental measurements (EPMA) and diffusion calculations (DICTRA{sup TM}) to investigate the effect of hard particle addition and its dissolution, as well as the formation of M{sub 6}C carbides on the properties of two different PM tool steel coatings hot extruded with a 1.2714 steel bar. A carburization effect resulting from the W{sub 2}C hard particles is responsible for an increase of the 1.2344 steel matrix hardness. The mechanical properties of the interface region between coating matrix and substrate are influenced by chemical interdiffusion of carbon and other alloying elements occurring during heat treatment.

  10. Changes in the functional properties and antinutritional factors of extruded hard-to-cook common beans (Phaseolus vulgaris, L.).

    Science.gov (United States)

    Batista, Karla A; Prudêncio, Sandra H; Fernandes, Kátia F

    2010-04-01

    The biochemical and functional properties of 2 hard-to-cook common bean cultivars (Phaseolus vulgaris, L.) were investigated after the extrusion process. Beans of BRS pontal and BRS grafite cultivars were milled and extruded at 150 degrees C, with a compression ratio screw of 3 : 1, 5-mm die, and screw speed of 150 rpm. Extrudate flours were evaluated for water solubility (WS), water absorption index (WAI), oil absorption capacity (OAC), foaming capacity (FC), emulsifying activity (EA), antinutritional factors, and in vitro protein and starch digestibility. Results indicated that the extrusion significantly decreased antinutrients such as phytic acid, lectin, alpha-amylase, and trypsin inhibitors, reduced the emulsifying capacity and eliminated the FC in both BRS pontal and BRS grafite cultivars. In addition, the WS, WAI, and in vitro protein and starch digestibility were improved by the extrusion process. These results indicate that it is possible to produce new extruded products with good functional and biochemical properties from these common bean cultivars. PMID:20492281

  11. Expansion and functional properties of extruded snacks enriched with nutrition sources from food processing by-products.

    Science.gov (United States)

    Korkerd, Sopida; Wanlapa, Sorada; Puttanlek, Chureerat; Uttapap, Dudsadee; Rungsardthong, Vilai

    2016-01-01

    Rich sources of protein and dietary fiber from food processing by-products, defatted soybean meal, germinated brown rice meal, and mango peel fiber, were added to corn grit at 20 % (w/w) to produce fortified extruded snacks. Increase of total dietary fiber from 4.82 % (wb) to 5.92-17.80 % (wb) and protein from 5.03 % (wb) to 5.46-13.34 % were observed. The product indicated high expansion and good acceptance tested by sensory panels. There were 22.33-33.53 and 5.30-11.53 fold increase in the phenolics and antioxidant activity in the enriched snack products. The effects of feed moisture content, screw speed, and barrel temperature on expansion and nutritional properties of the extruded products were investigated by using response surface methodology. Regression equations describing the effect of each variable on the product responses were obtained. The snacks extruded with feed moisture 13-15 % (wb) and extrusion temperature at 160-180 °C indicated the products with high preference in terms of expansion ratio between insoluble dietary fiber and soluble dietary fiber balance. The results showed that the by-products could be successfully used for nutritional supplemented expanded snacks. PMID:26787975

  12. Effect of Malting and Nixtamalization Processes on the Physicochemical Properties of Instant Extruded Corn Flour and Tortilla Quality.

    Science.gov (United States)

    Rodríguez-Martínez, Nicolás Alberto; Salazar-García, María Guadalupe; Ramírez-Wong, Benjamín; Islas-Rubio, Alma Rosa; Platt-Lucero, Luis Carlos; Morales-Rosas, Ignacio; Marquez-Melendez, Rubén; Martínez-Bustos, Fernando

    2015-09-01

    This research aimed to prepare instant flour from malted and raw (un-malted) corn flours nixtamalized by the extrusion process and evaluate the effect on the physicochemical properties of tortillas prepared using these flours. White maize was malted for 24 h, dried at 50 ± 1 °C, and ground. Subsequently, 0.3 % lime and 25 or 30 % water were added to ground malted or un-malted corn, and the mixture was refrigerated (4 °C) for 12 h. These samples were nixtamalized by an extrusion process in a single screw extruder at two temperature profiles within four heating zones, TP1 (60, 60, 70, and 80 °C) and TP2 (60, 70, 80, and 90 °C), to obtain corn flour. Water was added to the extruded corn flours to make a dough, or masa, and the masa was then molded and baked to obtain tortillas. The corn flours were characterized according to their ability to absorb water and viscosity profile (RVA). The firmness and rollability after 2 and 24 h of storage were determined, and a sensory evaluation was conducted. The malted corn flour extruded with a 25 % moisture content and TP2 temperature profile yielded tortillas with the best firmness and rollability. In conclusion, the changes during the malting of corn grain and the nixtamalization by the extrusion process improved the water absorption capacity of flours and textural properties of the tortilla and produced a product with acceptable sensory properties. PMID:26059113

  13. Low cycle fatigue and strengthening mechanism of cold extruded large diameter internal thread of Q460 steel

    Science.gov (United States)

    Miao, Hong; Mei, Qing; Yuan, Jingyun; Zheng, Zaixiang; Jin, Yifu; Zuo, Dunwen

    2016-05-01

    large diameter internal thread of high-strength steel(LDITHSS) manufactured by traditional methods always has the problems of low accuracy and short life. Compared with traditional methods, the cold extrusion process is an effective means to realize higher accuracy and longer life. The low-cycle fatigue properties of LDITHSS are obtained by experiments, and the initiation and propagation of fatigue cracks are observed by scanning electron microscope(SEM). Based on the mechanical properties, surface microstructure and residual stress, the strengthening mechanism of cold extruded large diameter internal thread(LDIT) is discussed. The results show that new grains or sub-grains can be formed on the surface of LDIT due to grain segmentation and grain refinement during cold extrusion. The fibrous structures appear as elongated and streamlined along the normal direction of the tooth surface which leads to residual compressive stress on the extruded surface. The maximum tension stress of LDIT after cold extrusion is found to be 192.55 kN. Under low stress cycling, the yield stress on thread increases, the propagation rate of crack reduces, the fatigue life is thus improved significantly with decreasing surface grain diameter and the average fatigue life increases to 45.539×103 cycle when the maximum applied load decreases to 120 kN. The low cycle fatigue and strengthening mechanism of cold extruded LDIT revealed by this research has significant importance to promote application of internal thread by cold extrusion processing.

  14. Effects of extruded linseed dietary supplementation on milk yield, milk quality and lipid metabolism of dairy cows

    Directory of Open Access Journals (Sweden)

    N. Brogna

    2010-04-01

    Full Text Available Twenty Italian Friesian dairy cows were used in an experimental trial to study the effects of extruded linseed dietary supplementation on milk production, milk quality and fatty acid (FA percentages of milk fat and total plasma lipids and plasma phospholipids. Control cows were fed a corn silage based total mixed ration (TMR while treated animals also received 700g/head/d of extruded linseed supplementation. Feed intake was similar between groups. Milk yields was tendentially greater for cows fed extruded linseed. Milk urea content (P<0.05 were reduced by treatment. Results showed a significant increase n-3 FA concentration (particularly alpha linolenic acid and a significant reduction of n-6/n-3 FA ratio in milk fat, total plasma lipids and plasma phospholipids (P<0.001; moreover a reduction trend (P<0.1 of arachidonic acid concentrations was observed in milk fat, total plasma lipids and plasma phospholipids. At last, treatment enhanced milk fat conjugated linoleic acid (CLA percentage (P<0.05.

  15. Effect of Amaranth addition on the nutritional composition and consumer acceptability of extruded provitamin A-biofortified maize snacks

    Directory of Open Access Journals (Sweden)

    Daniso BESWA

    2016-01-01

    Full Text Available The objective of this study was to determine the effect of adding Amaranth leaf powder on the nutrient content and consumer acceptability of extruded provitamin A-biofortified (PVA maize snacks. Flours of four varieties of PVA maize were composited with Amaranth leaf powder at 0, 1 and 3% (w/w substitution of, respectively, and extruded into snacks. The ash content of the snacks increased from 0.53 g/100 g-0.58 g/100 g to 0.650 g/100g-89 g/100 g and protein content increased from 9.12 g/100 g-10.94 g/100 g when Amaranth was increased from 0% to 3%. Similarly, lysine content increased from 0.10 g/100 g to 0.17 g/100 g, whilst methionine increased from 0.14 g/100 g to 0.19 g/100 g. The provitamin A content of the snacks ranged from 1.29 µg/g to 1.40 µg/g at 0% Amaranth and 1.54 µg/g to 1.78 µg/g at 3% Amaranth. The acceptability of the snacks decreased with increasing Amaranth concentration, only a very small proportion (2-8% of the panel liked the snacks extremely. PVA maize with added Amaranth leaf powder has a potential for use in nutritious and healthy extruded snacks, but the consumer acceptability of the snacks should be improved.

  16. Raw and extruded pea (Pisum sativum and lupin (Lupinus albusvar. Multitalia seeds as protein sources in weaned piglets’ diets: effect on growth rate and blood parameters

    Directory of Open Access Journals (Sweden)

    Gianfranco Piva

    2010-01-01

    Full Text Available The 42 days trial was carried out using 140 piglets weaned at 28 days of age. The piglets were allocated according to  weight and sex to the 5 dietary treatments with 7 replicates for each treatments (4 pens x 4 castrated males and 3 pens  x 4 females. The piglets were fed according to the following experimental design: 1 control diet (CTR with soybean  meal (SBM 44% c.p. as protein source; 2 CRT diets with 200 g/kg of raw pea (Pisum sativum (RP; 3 CTR diet with  200 g/kg extruded pea (EP; 4 CRT diet with 170 g/kg raw lupin (Lupinus albusvar. Multitalia (RL; 5 CTR diet with  170 g/kg of extruded lupin (EL. During the trial, animals were weighed at 0 - 21 and 42 days from the start of the trial.  Feed intake was monitored and feed conversion ratio was calculated for the periods 0-21 d and 22-42 d. At the end of  the trial, blood samples were taken for 14 animals for each dietary treatment (2 animals per replicate and analysed for  total protein, urea and liver activity (ALT, AST and ALP parameters. Average daily weight gain and feed intake did not  differ according to dietary treatments whereas during the total experimental period (0-42 d, feed conversion ratio was  higher for EP vsCTR diet (2.35 vs2.09, respectively; P   compared with diets containing the raw ingredients did not differ. Feed conversion ratio for the RP was numerically high-  er than for the EP (2.35 vs2.16 and 2.76 vs2.32, respectively during 22-42 d and 0-42 d periods. Blood parameters  did not show significant difference among dietary treatments except for higher total protein for CTR diet vsRL diet, EL  and RP (67.3 vs62.2, 62.8 and 63.6 g/l, respectively; PvsRL  and RL (4.7 vs3.7 and 3.8 mmol/l respectively; P 

  17. Influence of pea hulls on the twin screw extrusion-cooking process of cereal mixtures and the physical properties of the extrudate

    Directory of Open Access Journals (Sweden)

    Zarzycki P.

    2004-03-01

    Full Text Available The aim of the study was to determine the influence of the proportion of pea hulls, moisture, the barrel temperature and the diameter of the die, in the course of the process along with the possibilities for stabilising the extrusion-cooking conditions and the physical extrudate properties. Pea hulls ranging from 20 to 80% give the correct stabilisation in extrusion-cooking conditions and obtain a range of varied products with different physical and functional properties. An increase of pea hulls in extruded mixtures leads to a lowering of the radial expansion ratio and an increase in specific density, a worsening of the extrudate's texture, a decrease in the water solubility index of dry mass (WSI and a lowering of the water absorption index of the extruded products (WAI. An increase in processing temperatures in the range of 120-220°C contributes to a slight increase in the radial expansion ratio, a lowering of the extrudate's specific density, an improvement in product crispness and an increase of the WSI. The moisture (20-26% generates the product's structure with only a slight expansion and causes changes in the extrudate’s WSI and WAI.

  18. Lead markets in age-based innovations

    OpenAIRE

    Levsen, Nils; Herstatt, Cornelius

    2014-01-01

    The trend of population aging is affecting an increasing number of countries around the world, especially advanced economies. One consequence of a growing population share of aged persons is a shift in consumer needs, reflected by a rising number of products and services designed particularly for elderly users. Thus, population aging is a catalyst for new markets and a driver of innovation. A common objective of such age-based innovations is the delay of an age-associated decline in individua...

  19. Ceramic catalyst materials

    Energy Technology Data Exchange (ETDEWEB)

    Sault, A.G.; Gardner, T.J. [Sandia National Laboratories, Albuquerque, NM (United States); Hanprasopwattanna, A.; Reardon, J.; Datye, A.K. [Univ. of New Mexico, Albuquerque, NM (United States)

    1995-08-01

    Hydrous titanium oxide (HTO) ion-exchange materials show great potential as ceramic catalyst supports due to an inherently high ion-exchange capacity which allows facile loading of catalytically active transition metal ions, and an ability to be cast as thin films on virtually any substrate. By coating titania and HTO materials onto inexpensive, high surface area substrates such as silica and alumina, the economics of using these materials is greatly improved, particularly for the HTO materials, which are substantially more expensive in the bulk form than other oxide supports. In addition, the development of thin film forms of these materials allows the catalytic and mechanical properties of the final catalyst formulation to be separately engineered. In order to fully realize the potential of thin film forms of titania and HTO, improved methods for the deposition and characterization of titania and HTO films on high surface area substrates are being developed. By varying deposition procedures, titania film thickness and substrate coverage can be varied from the submonolayer range to multilayer thicknesses on both silica and alumina. HTO films can also be formed, but the quality and reproducibility of these films is not nearly as good as for pure titania films. The films are characterized using a combination of isopropanol dehydration rate measurements, point of zero charge (PZC) measurements, BET surface area, transmission electron microscopy (TEM), and elemental analysis. In order to assess the effects of changes in film morphology on catalytic activity, the films are being loaded with MoO{sub 3} using either incipient wetness impregnation or ion-exchange of heptamolybdate anions followed by calcining. The MoO{sub 3} is then sulfided to form MOS{sub 2}, and tested for catalytic activity using pyrene hydrogenation and dibenzothiophene (DBT) desulfurization, model reactions that simulate reactions occurring during coal liquefaction.

  20. Magnetically Recoverable Ruthenium Catalysts in Organic Synthesis

    OpenAIRE

    Dong Wang; Didier Astruc

    2014-01-01

    Magnetically recyclable catalysts with magnetic nanoparticles (MNPs) are becoming a major trend towards sustainable catalysts. In this area, recyclable supported ruthenium complexes and ruthenium nanoparticles occupy a key place and present great advantages compared to classic catalysts. In this micro-review, attention is focused on the fabrication of MNP-supported ruthenium catalysts and their catalytic applications in various organic syntheses.

  1. Thermally-induced microstructural changes in a three-way automotive catalyst

    Energy Technology Data Exchange (ETDEWEB)

    More, K.L.; Kenik, E.A.; Coffey, D.W.; Geer, T.S. [Oak Ridge National Lab., TN (United States); Theis, J.; LaBarge, W.; Beckmeyer, R. [Delphi Automotive Systems, Flint, MI (United States)

    1997-12-01

    The use of advanced electron microscopy techniques to characterize both the bulk and near-atomic level microstructural evolution of catalyst materials during different dynamometer/vehicle aging cycles is an integral part of understanding catalyst deactivation. The study described here was undertaken to evaluate thermally-induced microstructural changes which caused the progressive loss of catalyst performance in a three-way automotive catalyst. Several different catalyst processing variables, for example changing the washcoat ceria content, were also evaluated as a function of aging cycle and thermal history. A number of thermally-induced microstructural changes were identified using high resolution electron microscopy techniques that contributed to the deactivation of the catalyst, including sintering of all washcoat constituents, {gamma}-alumina transforming to {alpha}-, {beta}-, and {delta}-alumina, precious metal redistribution, and constituent encapsulation. The data accumulated in this study have been used to correlate microstructural evolution with thermal history and catalyst performance during various aging cycles and to subsequently evaluate different washcoat formulations for increased thermal stability.

  2. The Effect of Aging Time on the Properties of Mg-Al-CO3 Layered Double Hydroxides and Its Application as a Catalyst Support for TiO2.

    Science.gov (United States)

    Guo, Yang; Cui, Xianlu; Li, Yaogang; Zhang, Qinghong; Wang, Hongzhi

    2016-06-01

    By using chloride salts as the raw materials, Mg-Al-CO3 layered double hydroxides (Mg-Al-CO3 LDHs) with Mg/Al molar ratio 2:1 were prepared via a coprecipitation method. The effect of the aging time on the crystallinity, particle size, chemical composition, morphology, specific surface area, and pore size distribution of Mg-Al-CO3 LDHs were studied in details. The effect of aging time during LDHs preparation process on adsorption capacity of LDHs and their calcined products (mixed metal oxide, MMO) were investigated by removing the pollutant acid red 1 (AR1) from aqueous solution. The results showed that LDHs prepared at 90 degrees C for 4 h (LDH-4) had a higher specific area of 103.7 m2/g and LDHs prepared at 90 degrees C for 8 h (LDH-8) exhibited well-formed hexagonal crystals with a relative smooth surface. The LDH-4 and its calcined product are more effective in removing AR1 than LDH-8, which is related to the differences in their specific surface area. Meanwhile, anatase TiO2-coated MMO with MMO/TiO2 mass ratios at 1:1 and.2:1 were prepared via a chemical precipitation route in the presence of LDH, the composites showed an efficiently photocatalytic activity in the removal of AR1. PMID:27427611

  3. Duplex steam reformer: alternate catalyst

    International Nuclear Information System (INIS)

    The manufacturing feasibility of a duplex steam reformer tube for potential use in a high temperature gas cooled reactor has been successfully demonstrated. This technique consists of explosively expanding the inner tube into the outer tube. To successfully achieve the desired 0 to 3 mil radial gap between the tubes it is necessary to perform the expansion in two steps with an intermediate anneal. A catalyst design that would have replaced the conventional Raschig rings with a metal supported catalyst has been evaluated and it has been concluded that further development and testing are needed before fabrication of a full scale prototype is warranted. Consequently, the immediate efforts are directed towards reevaluating the incentives for developing a catalyst and the probability of successfully developing a catalyst that could be used for steam reforming

  4. Alumina supported iridium catalysts - preparation

    International Nuclear Information System (INIS)

    This report describes the method employed in the preparation of alumina supported iridium catalysts, with metal contents between 30 and 40%, that will be used for hydrazine monopropellant decomposition. (author)

  5. Experimental Design for Evaluation of Co-extruded Refractory Metal/Nickel Base Superalloy Joints

    Energy Technology Data Exchange (ETDEWEB)

    ME Petrichek

    2005-12-16

    a critical thickness (0.0005 in.). A diffusion barrier that exceeded this thickness would likely fail. The joint fabrication method must therefore mechanically bond the two materials causing little or no interdiffusion upon formation. Co-extrusion fits this description since it forms a mechanical joint between two materials by using heat and pressure. The two materials to be extruded are first assembled and sealed within a co-extrusion billet which is subsequently heated and then extruded through a die. For a production application, once the joint is formed, it is dejacketed to remove the outer canister. The remaining piece consists of two materials bonded together with a thin diffusion barrier. Therefore, the long-term stability of the joint is determined primarily by the kinetics of interdiffusion reaction between the two materials. An experimental design for co-extrusion of refractory metals and nickel-based superalloys was developed to evaluate this joining process and determine the long-term stability of the joints.

  6. Experimental Design for Evaluation of Co-extruded Refractory Metal/Nickel Base Superalloy Joints

    International Nuclear Information System (INIS)

    a critical thickness (0.0005 in.). A diffusion barrier that exceeded this thickness would likely fail. The joint fabrication method must therefore mechanically bond the two materials causing little or no interdiffusion upon formation. Co-extrusion fits this description since it forms a mechanical joint between two materials by using heat and pressure. The two materials to be extruded are first assembled and sealed within a co-extrusion billet which is subsequently heated and then extruded through a die. For a production application, once the joint is formed, it is dejacketed to remove the outer canister. The remaining piece consists of two materials bonded together with a thin diffusion barrier. Therefore, the long-term stability of the joint is determined primarily by the kinetics of interdiffusion reaction between the two materials. An experimental design for co-extrusion of refractory metals and nickel-based superalloys was developed to evaluate this joining process and determine the long-term stability of the joints

  7. Catalysts based on mesoporous aluminosilicates for the hydroisomerization and hydrodearomatization processes

    Energy Technology Data Exchange (ETDEWEB)

    Vilesov, A.S.; Kulikov, A.B. [Russian Academy of Sciences (Russian Federation). A.V. Topchiev Inst. of Petrochemical Synthesis; Ostroumova, V.A.; Baranova, S.V.; Lysenko, S.V.; Kardashev, S.V.; Lasarev, A.V.; Egazaryants, S.V.; Karakhanov, E.A. [Lomonosov Moscow State Univ. (Russian Federation). Chemistry Dept.; Maximov, A.L. [Russian Academy of Sciences (Russian Federation). A.V. Topchiev Inst. of Petrochemical Synthesis; Lomonosov Moscow State Univ. (Russian Federation). Chemistry Dept.

    2011-07-01

    In the present work the activity of bifunctional catalysts based on mesoporous aluminosilicates in the hydroisomerization of n-alkanes and the hydrodearomatization (HDA) process has been investigated. The structured mesoporous aluminosilicates (Si/Al = 5/30) were prepared using hexadecylamine and Pluronic P{sub 123} as templates, with a specific surface area up to 1030 m{sup 2}/g and a pore size from 33 to 84 A. Bifunctional catalysts were prepared in the form of extrudates using boehmite as a binder with the platinum content of 0,5% by mass. The experiment was carried out in a flow reactor. The highest selectivity in the isomerization of n-dodecane and n-hexadecane was shown by catalysts based on mesoporous aluminosilicates with Si/Al =10 and 20. In the hydrogenation of a model feed of 10% (wt.) naphthalene in benzene, it was established that, depending on the module aluminosilicate, the conversion of naphthalene to decalin and tetralin may proceed quantitatively with no conversion of benzene to cyclohexane. Selectivity was in the range from 55 to 90% by decalin, and from 10 to 45% by tetralin. We found the conditions under which the only product of the hydrogenation of naphthalene is tetralin, but the conversion of naphthalene was up to 65%. Also, the activity of such catalysts for hydroisomerization and hydrodearomatization processes on the hydrotreated straight-run diesel fraction was investigated. It was established, that due to hydroisomerization, the maximum filtration temperature goes under -38 C, that allows to use it as a component of winter and arctic diesel fuels. (orig.)

  8. Separately supported polymetallic reforming catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Kresge, C. T.; Krishnamurthy, S.; McHale, W. D.

    1985-01-15

    There is provided, in accordance with the present invention, a catalyst composition made up of a mixture of two components, one component comprising a minor proportion of platinum and rhenium on a support and the second component comprising a minor proportion of iridium and rhenium on a separate support. A process for reforming a charge stock, such as naphtha, utilizing such catalyst is also provided.

  9. Precision extruding deposition (PED) fabrication of polycaprolactone (PCL) scaffolds for bone tissue engineering

    International Nuclear Information System (INIS)

    Bone tissue engineering is an emerging field providing viable substitutes for bone regeneration. Recent advances have allowed scientists and engineers to develop scaffolds for guided bone growth. However, success requires scaffolds to have specific macroscopic geometries and internal architectures conducive to biological and biophysical functions. Freeform fabrication provides an effective process tool to manufacture three-dimensional porous scaffolds with complex shapes and designed properties. A novel precision extruding deposition (PED) technique was developed to fabricate polycaprolactone (PCL) scaffolds. It was possible to manufacture scaffolds with a controlled pore size of 350 μm with designed structural orientations using this method. The scaffold morphology, internal micro-architecture and mechanical properties were evaluated using scanning electron microscopy (SEM), micro-computed tomography (micro-CT) and mechanical testing, respectively. An in vitro cell-scaffold interaction study was carried out using primary fetal bovine osteoblasts. Specifically, the cell proliferation and differentiation was evaluated by Alamar Blue assay for cell metabolic activity, alkaline phosphatase activity and osteoblast production of calcium. An in vivo study was performed on nude mice to determine the capability of osteoblast-seeded PCL to induce osteogenesis. Each scaffold was implanted subcutaneously in nude mice and, following sacrifice, was explanted at one of a series of time intervals. The explants were then evaluated histologically for possible areas of osseointegration. Microscopy and radiological examination showed multiple areas of osseous ingrowth suggesting that the osteoblast-seeded PCL scaffolds evoke osteogenesis in vivo. These studies demonstrated the viability of the PED process to fabricate PCL scaffolds having the necessary mechanical properties, structural integrity, and controlled pore size and interconnectivity desired for bone tissue engineering

  10. Precision extruding deposition (PED) fabrication of polycaprolactone (PCL) scaffolds for bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Shor, Lauren; Gueceri, Selcuk; Chang, Robert; Sun Wei [Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA (United States); Gordon, Jennifer; Kang Qian; Hartsock, Langdon; An Yuehuei [Department of Orthopedic Surgery, Medical University of South Carolina, Charleston, SC (United States)], E-mail: st963bya@drexel.edu, E-mail: guceri@drexel.edu, E-mail: rcc34@drexel.edu, E-mail: sunwei@drexel.edu, E-mail: kangqk@musc.edu, E-mail: hartsock@musc.edu, E-mail: any@musc.edu

    2009-03-01

    Bone tissue engineering is an emerging field providing viable substitutes for bone regeneration. Recent advances have allowed scientists and engineers to develop scaffolds for guided bone growth. However, success requires scaffolds to have specific macroscopic geometries and internal architectures conducive to biological and biophysical functions. Freeform fabrication provides an effective process tool to manufacture three-dimensional porous scaffolds with complex shapes and designed properties. A novel precision extruding deposition (PED) technique was developed to fabricate polycaprolactone (PCL) scaffolds. It was possible to manufacture scaffolds with a controlled pore size of 350 {mu}m with designed structural orientations using this method. The scaffold morphology, internal micro-architecture and mechanical properties were evaluated using scanning electron microscopy (SEM), micro-computed tomography (micro-CT) and mechanical testing, respectively. An in vitro cell-scaffold interaction study was carried out using primary fetal bovine osteoblasts. Specifically, the cell proliferation and differentiation was evaluated by Alamar Blue assay for cell metabolic activity, alkaline phosphatase activity and osteoblast production of calcium. An in vivo study was performed on nude mice to determine the capability of osteoblast-seeded PCL to induce osteogenesis. Each scaffold was implanted subcutaneously in nude mice and, following sacrifice, was explanted at one of a series of time intervals. The explants were then evaluated histologically for possible areas of osseointegration. Microscopy and radiological examination showed multiple areas of osseous ingrowth suggesting that the osteoblast-seeded PCL scaffolds evoke osteogenesis in vivo. These studies demonstrated the viability of the PED process to fabricate PCL scaffolds having the necessary mechanical properties, structural integrity, and controlled pore size and interconnectivity desired for bone tissue engineering.

  11. Twin Screw Extruders as Continuous Mixers for Thermal Processing: a Technical and Historical Perspective.

    Science.gov (United States)

    Martin, Charlie

    2016-02-01

    Developed approximately 100 years ago for natural rubber/plastics applications, processes via twin screw extrusion (TSE) now generate some of the most cutting-edge drug delivery systems available. After 25 or so years of usage in pharmaceutical environments, it has become evident why TSE processing offers significant advantages as compared to other manufacturing techniques. The well-characterized nature of the TSE process lends itself to ease of scale-up and process optimization while also affording the benefits of continuous manufacturing. Interestingly, the evolution of twin screw extrusion for pharmaceutical products has followed a similar path as previously trodden by plastics processing pioneers. Almost every plastic has been processed at some stage in the manufacturing train on a twin screw extruder, which is utilized to mix materials together to impart desired properties into a final part. The evolution of processing via TSEs since the early/mid 1900s is recounted for plastics and also for pharmaceuticals from the late 1980s until today. The similarities are apparent. The basic theory and development of continuous mixing via corotating and counterrotating TSEs for plastics and drug is also described. The similarities between plastics and pharmaceutical applications are striking. The superior mixing characteristics inherent with a TSE have allowed this device to dominate other continuous mixers and spurred intensive development efforts and experimentation that spawned highly engineered formulations for the commodity and high-tech plastic products we use every day. Today, twin screw extrusion is a battle hardened, well-proven, manufacturing process that has been validated in 24-h/day industrial settings. The same thing is happening today with new extrusion technologies being applied to advanced drug delivery systems to facilitate commodity, targeted, and alternative delivery systems. It seems that the "extrusion evolution" will continue for wide

  12. Ultrasonically Improved Sieving of Food Materials for Manufacturing of Direct Expanded Extrudates

    Directory of Open Access Journals (Sweden)

    Mladen Brnčić

    2009-12-01

    Full Text Available Particle size distribution of raw materials plays an important role in extrusion process during direct expanded extrudates manufacturing. In most of the food industries all types of fl ours come in a production plant packed in bags with certain checkmarks that consist of average size of particles expressed in μm.That particle size range is very relative, because mostly it means that size of most frequent particles is expressed. During extrusion processing of corn fl our and whey or soy proteins blends are interject, then it is very important to know precise particle size of the interjected blends. If it does not match, raw materials should be sieved and particular fractions separated.To obtain the best fraction of corn fl our for extrusion processing (200 – 450 μm, sieving was conducted in shaker “Analysette 3” with sieving times of 5, 10 and 15 minutes. For each of these three measurements an agglomerate creation was spotted, followed by the major remain of the sample at the mesh of 450 μm. Sieving was repeated with aid of ultrasound (250 W, using power generator and by ultrasonic ring with transducer (“UIS 250 L” mounted on the sieves. Sieving was conducted again with sieving times of 5, 10 and 15 minutes, and variable amplitude of works of 25, 50 and 75% for ultrasound. Within each of these nine measurements a partial or complete agglomerate breakdown was achieved, and an optimal fraction for extrusion processing was acquired. For the desirable particle size fraction in range of 200 – 450 μm for extrusion, under the conditions of 10 and 15 minutes of sieving time with amplitude work of 75%, the most of the sample remained within desirable range (83,79% and 83.4%.

  13. Strain-hardening and warm deformation behaviors of extruded Mg–Sn–Yb alloy sheet

    Directory of Open Access Journals (Sweden)

    Jing Jiang

    2014-06-01

    Full Text Available Strain-hardening and warm deformation behaviors of extruded Mg–2Sn–0.5Yb alloy (at.% sheet were investigated in uniaxial tensile test at temperatures of 25–250 °C and strain rates of 1 × 10−3 s−1–0.1 s−1. The data fit with the Kocks–Mecking type plots were used to show different stages of strain hardening. Besides III-stage and IV-stage, the absence of the II-stage strain hardening at room temperature should be related to the sufficient dynamic recrystallization during extrusion. The decrease of strain hardening ability of the alloy after yielding was attributed to the reduction of dislocation density with increasing testing temperature. Strain rate sensitivity (SRS was significantly enhanced with increasing temperature, and the corresponding m-value was calculated as 0.07–0.12, which indicated that the deformation mechanism was dominated by the climb-controlled dislocation creep at 200 °C. Furthermore, the grain boundary sliding (GBS was activated at 250 °C, which contributed to the higher SRS. The activation energy was calculated as 213.67 kJ mol−1, which was higher than that of lattice diffusion or grain boundary self-diffusion. In addition, the alloy exhibited a quasi superplasticity at 250 °C with a strain rate of 1 × 10−3 s−1, which was mainly related to the fine microstructure and the presence of the Mg2Sn and Mg2(Sn,Yb particles.

  14. Mechanical Behavior and Microstructural Analysis of Extruded AZ31B Magnesium Alloy Processed by Backward Extrusion

    Science.gov (United States)

    Zhou, Ping; Beeh, Elmar; Friedrich, Horst E.; Grünheid, Thomas

    2016-07-01

    This study investigates the mechanical behavior of an extruded AZ31B magnesium alloy profile at various strain rates from 0.001 to 375/s. The electron backscatter diffraction analysis revealed that the profile has \\{ { 0 0 0 1} \\}extrusion direction (ED), the profile shows the highest yield strength (YS) but the lowest total elongation at fracture (TE) due to a hard activation of non-basal slip and \\{ { 1 0overline{1} 1} \\}< { 1 0overline{1} overline{2} } rangle twinning; in the diagonal direction (DD), it shows the lowest ultimate tensile strength (UTS) but the highest TE due to an easy activation of basal slip; in the transverse direction (TD), it shows the lowest YS due to an easy activation of \\{ {10overline{1} 2} \\}< {10overline{1} overline{1} } rangle twinning. Moreover, the number of twins increases with the increasing strain rate. This indicates that deformation twinning becomes prevalent to accommodate high-rate deformation. Due to the different deformation mechanisms, the profile exhibits an orientation-dependent effect of strain rate on the mechanical properties. A positive effect of strain rate on the YS and UTS was found in the ED, while the effect of strain rate on the YS is negligible in the DD and TD. The TE in the ED, DD, and TD decreases in general as the strain rate increases. Fractographic analysis under a scanning electron microscope revealed that the fracture is a mixed mode of ductile and brittle fracture, and the magnesium oxide inclusions could be the origins of the fracture.

  15. Effect of an extruded pea or rice diet on postprandial insulin and cardiovascular responses in dogs.

    Science.gov (United States)

    Adolphe, J L; Drew, M D; Silver, T I; Fouhse, J; Childs, H; Weber, L P

    2015-08-01

    Peas are increasing in popularity as a source of carbohydrate, protein and fibre in extruded canine diets. The aim of this study was to test the health effects of two canine diets with identical macronutrient profiles, but containing either yellow field peas or white rice as the carbohydrate source on metabolism, cardiovascular outcomes and adiposity. First, the acute glycemic, insulinemic and cardiovascular responses to the pea- or rice-based diets were determined in normal weight beagles (n = 7 dogs). The glycemic index did not differ between the pea diet (56 ± 12) and rice diet (63 ± 9). Next, obese beagles (n = 9) were fed the yellow field pea diet or white rice diet ad libitum for 12 weeks in a crossover study. Adiposity (measured using computed tomography), metabolic (oral glucose tolerance test, plasma leptin, adiponectin, C-reactive protein) and cardiovascular assessments (echocardiography and blood pressure) were performed before and after each crossover study period. After 12 weeks on each diet, peak insulin (p = 0.05) and area under the curve (AUC) for insulin after a 10 g oral glucose tolerance test (p = 0.05) were lower with the pea than the rice diet. Diet did not show a significant effect on body weight, fat distribution, cardiovascular variables, adiponectin or leptin. In conclusion, a diet containing yellow field peas reduced the postprandial insulin response after glucose challenge in dogs despite continued obesity, indicating improved metabolic health. PMID:25475789

  16. Effect of preparation parameters on the microporous structure of Ni/SiO{sub 2} catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Castillon, F.F.; Bodganchikova, N. [Centro de Investigacion Cientifica y de Educacion Superior, Ensenada (Mexico); Fuentes, S.; Avalos, M. [Univ. Nacional Autonoma de Mexico, Ensenada (Mexico). Inst. de Fisica

    1996-12-31

    In this work the authors report the synthesis of Ni/SiO{sub 2} catalysts promoted by group 2 (IIA) cations (calcium and barium) which are currently used as hydrogenation catalysts. The effect of the preparation parameters-aging, base agent, and type of cation, on the surface area of catalysts--is evaluated. Catalysts were prepared by precipitation of the precursor silicic acid, along with nickel nitrate and calcium and barium carbonates, with NaOH, NH{sub 4}OH and Na{sub 2}CO{sub 3} as precipitating agents. Catalysts were characterized by diffuse reflectance spectra (DRS) and by BET-surface area measurements. Results are discussed in terms of sol-gel chemistry.

  17. Thermally stable single-atom platinum-on-ceria catalysts via atom trapping.

    Science.gov (United States)

    Jones, John; Xiong, Haifeng; DeLaRiva, Andrew T; Peterson, Eric J; Pham, Hien; Challa, Sivakumar R; Qi, Gongshin; Oh, Se; Wiebenga, Michelle H; Pereira Hernández, Xavier Isidro; Wang, Yong; Datye, Abhaya K

    2016-07-01

    Catalysts based on single atoms of scarce precious metals can lead to more efficient use through enhanced reactivity and selectivity. However, single atoms on catalyst supports can be mobile and aggregate into nanoparticles when heated at elevated temperatures. High temperatures are detrimental to catalyst performance unless these mobile atoms can be trapped. We used ceria powders having similar surface areas but different exposed surface facets. When mixed with a platinum/aluminum oxide catalyst and aged in air at 800°C, the platinum transferred to the ceria and was trapped. Polyhedral ceria and nanorods were more effective than ceria cubes at anchoring the platinum. Performing synthesis at high temperatures ensures that only the most stable binding sites are occupied, yielding a sinter-resistant, atomically dispersed catalyst. PMID:27387946

  18. Thermally stable single-atom platinum-on-ceria catalysts via atom trapping

    Energy Technology Data Exchange (ETDEWEB)

    Jones, John; Xiong, Haifeng; DelaRiva, Andrew; Peterson, Eric J.; Pham, Hien; Challa, Sivakumar R.; Qi, Gongshin; Oh, Se H.; Wiebenga, Michelle H.; Pereira Hernandez, Xavier I.; Wang, Yong; Datye, Abhaya K.

    2016-07-08

    Catalysts based on single atoms of scarce precious metals can lead to more efficient use through enhanced reactivity and selectivity. However, single atoms on catalyst supports can be mobile and aggregate into nanoparticles when heated at elevated temperatures. High temperatures are detrimental to catalyst performance unless these mobile atoms can be trapped. We used ceria powders having similar surface areas but different exposed surface facets. When mixed with a platinum/ aluminum oxide catalyst and aged in air at 800°C, the platinum transferred to the ceria and was trapped. Polyhedral ceria and nanorods were more effective than ceria cubes at anchoring the platinum. Performing synthesis at high temperatures ensures that only the most stable binding sites are occupied, yielding a sinter-resistant, atomically dispersed catalyst.

  19. The innovation catalysts.

    Science.gov (United States)

    Martin, Roger L

    2011-06-01

    A few years ago the software development company Intuit realized that it needed a new approach to galvanizing customers. The company's Net Promoter Score was faltering, and customer recommendations of new products were especially disappointing. Intuit decided to hold a two-day, off-site meeting for the company's top 300 managers with a focus on the role of design in innovation. One of the days was dedicated to a program called Design for Delight. The centerpiece of the day was a PowerPoint presentation by Intuit founder Scott Cook, who realized midway through that he was no Steve Jobs: The managers listened dutifully, but there was little energy in the room. By contrast, a subsequent exercise in which the participants worked through a design challenge by creating prototypes, getting feedback, iterating, and refining, had them mesmerized. The eventual result was the creation of a team of nine design-thinking coaches--"innovation catalysts"--from across Intuit who were made available to help any work group create prototypes, run experiments, and learn from customers. The process includes a "painstorm" (to determine the customer's greatest pain point), a "soljam" (to generate and then winnow possible solutions), and a "code-jam" (to write code "good enough" to take to customers within two weeks). Design for Delight has enabled employees throughout Intuit to move from satisfying customers to delighting them. PMID:21714388

  20. Outstanding low temperature HC-SCR of NOx over platinum-group catalysts supported on mesoporous materials expecting diesel-auto emission regulation

    International Nuclear Information System (INIS)

    Outstanding low temperature HC-SCR of NOx over platinum-group catalysts supported on mesoporous materials, which does not rely on the conventional NOx-absorption-reduction-catalysts, is presented for the purpose of de-NOx of diesel-auto emissions. The established catalysts basically consist of mesoporous silica or metal-substituted mesoporous silicates for supports and platinum for active species, which is operated under lean- and rich-conditions. The new catalysts are very active at 150-200oC and free from difficult problems of SOx-deactivation and hydrothermal ageing of the NOx-absorption-reduction catalyst. (author)

  1. Influence of ceria on the thermally durability of Pt/Rh automotive catalyst

    International Nuclear Information System (INIS)

    Full text: The use of cerium oxide as an oxygen storage component in automotive three-way catalysts has been well established. More recently the requirement of the three-way catalysts against the increase of the severity in emission standards has focused attention on the development of more active, durable catalysts. The thermally durability of Pt/Rh catalyst can be achieved by the utilization of thermally stable ceria as well as optimization of washcoat composition and structure in order to control the extent of interaction between PGM and ceria. In the present paper, we describe the influence of newly developed washcoat components and PGM interaction with ceria on catalytic performance. First, to clear that the interaction between PGM and ceria contributes to catalytic performance, several kinds of catalysts which have the varied interactions between PGM and ceria were prepared using engineered washcoat techniques and evaluated in the model gas reactor. It was obvious that the difference in performance among them after aging derived from a diversity of interactions between Pt, Rh, and ceria. Second, for the purpose of determining the thermally durability of the developed Pt/Rh catalyst, the catalysts including the current catalyst were aged under three different temperatures and evaluated on engine dynamometer. Result of engine dynamometer evaluation revealed that significant improvement in the thermal durability can be achieved by optimizing the PGM-ceria interaction. In conclusion, we recognize that a thermal durability of a three-way catalyst can be improved by the stabilization of proper PGM-ceria interaction after aging as well as the utilization of thermally durable ceria material

  2. Effect of Dynamic Center Region on the Flow and Mixing Efficiency in a New Tri-Screw Extruder Using 3D Finite Element Modeling

    Directory of Open Access Journals (Sweden)

    X. Z. Zhu

    2013-01-01

    Full Text Available Three-dimensional finite element modeling of polymer melt flowing in a new co-rotating tri-screw extruder was established with mesh superposition technique. Based on the particle tracking technology, three typical particle trajectories in the tri-screw extruder were calculated using a 4th-order-Runge-Kutta method to study the dynamic motions of the particles. Then the flow visualizations in the local center region were carried out. Moreover, the dispersive, distributive and stretching mixing efficiencies of the tri-screw and twin-screw extruders were compared, respectively. The results show that when the particles move from one screw to another, there are great abrupt changes in the velocities and displacements, which induce the abrupt change in the stress magnitude. Most of particles, which are initially distributed in the inlet plane of the center region, fast flow out the outlet and don’t pass through any screw. This special phenomenon induces a series of new characteristics in the residence time distribution (RTD, flow number, segregation scale and time averaged efficiency. In comparison with the twin-screw extruder, the tri-screw extruder has better mixing efficiency.

  3. Cobalt and KNO{sub 3} supported on alumina catalysts for diesel soot combustion

    Energy Technology Data Exchange (ETDEWEB)

    Grzona, Claudia B. [25 de mayo 284, INTEQUI-CONICET-UNSL, Facultad de Ingenieria y Ciencias Economico-Sociales, Villa Mercedes, 5730 (Argentina); Lick, Ileana D. [Calle 47 No 257, CINDECA (CCT-LaPlata-CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, La Plata, 1900 (Argentina); Castellon, Enrique Rodriguez [Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Facultad de Ciencias, Universidad de Malaga, Campus de Teatinos, Malaga, 29071 (Spain); Ponzi, Marta I. [25 de mayo 284, INTEQUI-CONICET-UNSL, Facultad de Ingenieria y Ciencias Economico-Sociales, Villa Mercedes, 5730 (Argentina); Ponzi, Esther N., E-mail: eponzi@quimica.unlp.edu.ar [Calle 47 No 257, CINDECA (CCT-LaPlata-CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, La Plata, 1900 (Argentina)

    2010-10-01

    The catalytic combustion of diesel soot was studied in the presence of fresh and aged catalysts: Co/Al{sub 2}O{sub 3}, KNO{sub 3}/Al{sub 2}O{sub 3} and Co/KNO{sub 3}/Al{sub 2}O{sub 3}. The catalysts were prepared by impregnation using nitrate solutions. The catalysts were characterized by X-ray diffraction, thermal programmed reduction, vibrational spectroscopy and X-ray photoelectron spectroscopy. Fresh and aged catalysts present high activity in presence of O{sub 2} and O{sub 2}/NO. The values of the combustion temperature decrease more than 200 deg. C with respect to that observed in the process without catalysis. The activity is associated with the presence of KNO{sub 3} and the role of this salt can be attributed to the contribution of NO{sub 3}{sup -}/NO{sub 2}{sup -} redox cycle.

  4. Cobalt and KNO3 supported on alumina catalysts for diesel soot combustion

    International Nuclear Information System (INIS)

    The catalytic combustion of diesel soot was studied in the presence of fresh and aged catalysts: Co/Al2O3, KNO3/Al2O3 and Co/KNO3/Al2O3. The catalysts were prepared by impregnation using nitrate solutions. The catalysts were characterized by X-ray diffraction, thermal programmed reduction, vibrational spectroscopy and X-ray photoelectron spectroscopy. Fresh and aged catalysts present high activity in presence of O2 and O2/NO. The values of the combustion temperature decrease more than 200 deg. C with respect to that observed in the process without catalysis. The activity is associated with the presence of KNO3 and the role of this salt can be attributed to the contribution of NO3-/NO2- redox cycle.

  5. Reducing the tension–compression yield asymmetry of extruded Mg–Zn–Ca alloy via equal channel angular pressing

    OpenAIRE

    L.B. Tong; M.Y. Zheng; S. Kamado; Zhang, D.P.; Meng, J; L. R. Cheng; Zhang, H. J.

    2015-01-01

    The influence of equal channel angular pressing on the tension–compression yield asymmetry of extruded Mg–5.3 Zn–0.6 Ca (weight percent) alloy has been investigated. The microstructure was obviously refined by the large strain during the equal channel angular pressing, accompanied with very fine Ca2Mg6Zn3 phases with average diameter of 70 nm. The weak tension–compression yield asymmetry after equal channel angular pressing is mainly attributed to the reduced volume fraction of extension twin...

  6. ASSESSMENT OF NATURAL RADIOACTIVITY IN CONCRETE BLOCK, EXTRUDED CLAY BRICK, AND MUD BRICK TAKEN FROM OGBOMOSO, SOUTHWESTERN, NIGERIA

    OpenAIRE

    Bolaji Omogbemiga AYINMODE; FAMAKINWA, Rebecca Oluwadamilola; Jonathan Olanipekun AJAYI

    2012-01-01

    This study evaluates the natural radioactivity in concrete block, extruded clay brick, and mud brick taken from Ogbomoso city. The six samples were collected from different part of the city, and were analyzed using highly sensitive HPGe gamma spectrometer. The mean activity concentration in Bq Kg -1 of 40K , 238 U (226Ra) and 232Th were 135.10 ± 3.23, 9.58 ± 3.16 and 14.30 ± 3.32 respectively in concrete block ; 66.34 ± 6.66, 6.81 ± 2.26 and 6.78 ± 2....

  7. Effect of microstructure on the mechanical and corrosion behaviors of a hot-extruded nickel aluminum bronze

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,the influence of microstructure on the corrosion behavior of a hotextruded nickel aluminum bronze was studied.Three kinds of samples subjected to the hot-extrusion,annealing and quenching conditions were prepared and immersion tests in 3.5% NaCl solution were carried out.Microstructures and corrosion surface morphologies of the samples were observed by SEM.It was found that the retained β martensite and(α+κⅢ) lamella eutectoid in the as hot-extruded material were eliminated after annealing,and...

  8. The twin-screw extruder, a continuous liquid/solid extractor and separator during sunflower (Helianthus annuus L.) biorefinery

    OpenAIRE

    Evon, Philippe; Labonne, Laurent; Vandenbossche, Virginie; Pontalier, Pierre-Yves; Rigal, Luc

    2015-01-01

    Biorefinery of sunflower whole plant can be conducted with water using a nine modules Clextral Evolum HT 53 twin-screw extruder (TSE). Aqueous extraction of oil is an environmentally cleaner alternative technology to solvent extraction. TSE carries out three unit operations: conditioning and grinding, liquid/solid (L/S) extraction and L/S separation. The compressing action by the reverse screws (CF2C) is essential for L/S separation. Positioned in module 9, CF2C screws push part of the mixtur...

  9. Extruded pea (Pisum sativum as alternative to soybean protein for dairy cows feeding in organic Alpine farms

    Directory of Open Access Journals (Sweden)

    Flaviana Gottardo

    2010-04-01

    Full Text Available The study evaluated the use of extruded pea as an alternative to soybean in the protein feeding of dairy cattle raised in organic Alpine farms. The research was carried out in a commercial organic dairy farm located in the Province of Trento (Northern Italy and it considered two separate periods of cows’ lactation: early and late lactation. According to the traditional management practice of alpine dairy herds with the seasonal calving of the cows in early winter, the former period was carried out during the cold season when cows were housed indoors, while the latter period started after the transfer of the entire herd to an alpine pasture for the summer grazing. In both periods, 16 cows of Rendena breed were equally assigned to 2 experimental groups. The dietary forage (meadow hay in early lactation or pasture in late lactation was supplemented to one group of cows with a Control concentrate in which soybean expeller, sunflower expeller and wheat bran were the main protein feeds. Soybean proteins were replaced by extruded peas in the Soy-free concentrate given to the other group of cows. The daily amount of concentrate was adjusted to the individual milk yield on a weekly basis adopting ratios of 0.360 and 0.125 kg of DM per kg of milk in early and late lactation periods, respectively. Cows receiving Soy-free concentrate showed a higher milk yield than the Control cows in both lactation periods (18.7 vs 17.5 kg/d in early lactation and 9.3 vs 8.6 kg/d on pasture, respectively. Milk fat and protein were not affected by the diet at any stage of lactation, while a higher concentration of milk urea was observed in milk samples taken from Soy-free cows in both periods of the study. This result could have been promoted by the higher soluble fraction of extruded pea proteins in comparison to that of soybean expeller. Cows feeding behaviour was monitored only in the early lactation period and despite of the different amount of concentrate consumed by

  10. Morphological and Mechanical Properties of Dispersion-Cast and Extruded Nafion Membranes Subjected to Thermal and Chemical Treatments

    OpenAIRE

    Osborn, Shawn James

    2009-01-01

    The focus of this research project was to investigate morphological and mechanical properties of both extruded and dispersion-cast Nafion® membranes. The project can be divided into three primary objectives; obtaining a fundamental understanding of the glass transition temperature of Nafion®, determining the effect of thermal annealing treatments on the morphology and mechanical properties of dispersion-cast Nafion®, and examination of dispersion-cast Nafion® subjected to an ex-situ, Fen...

  11. Relevance of lab-scale conical twin-screw extruder for thermoplastic STARCH/PLA blends rheology study

    OpenAIRE

    Chabrat, Elodie; Rouilly, Antoine; Evon, Philippe; Longieras, Antoine; Rigal, Luc

    2010-01-01

    International audience During the last decade, thermoplastic starch (TPS) has been studied more and more, alone and in blends. One key property of TPS is its viscosity. A lab-scale conical twin-screw extruder has been used to process polymers or blends of polymers at a small scale (7 cm3), and to measure their viscosity by pressure loss in a backflow channel. TPS has been tested at different temperatures (100-180°C) and for a 100-900s-1 shear rate range. One surprising result is the viscos...

  12. COMPARATIVE STUDY OF APICALLY EXTRUDED DEBRIS AND IRRIGANT AFTER USING TWO ROTARY SYSTEMS (K3, RaCe)

    OpenAIRE

    Elka N. Radeva; Radosveta I. Vassileva

    2014-01-01

    The aim of this in vitro study was to establish and compare the amount of debris and irrigant extruded apically after root canal preparation with two rotary systems (K3 and RaCe). Methods: Two groups of 24 extracted teeth with single canals were used. In group 1 (12 teeth) the root canals were instrumented using nickel-titanium K3 rotary instruments and “crown-down” technique. In group 2 (12 teeth) the root canals were instrumented using nickel-titanium RaCe rotary instruments and “crown...

  13. Interaction between plasticized polyvinyl chloride waterproofing membrane and extruded polystyrene board, in the inverted flat roof

    Directory of Open Access Journals (Sweden)

    Pedrosa, A.

    2014-12-01

    Full Text Available The inverted flat roof is a constructive system widely used in flat roof construction. In this constructive solution, the insulation is placed over the waterproofing material as a protection. It is believed that this solution provides a longer life cycle; given the fact that it limits the thermal variation the waterproofing material bears up to the end of its life cycle. Consequently, the result will be providing a longer life to the waterproofing membrane. This constructive solution always incorporates polymers or other materials with a thermoplastic addition in their composition. Some polymers show interactions between them that can affect their integrity, and, at the same time, the bulk of the polymeric materials are incompatible. The extruded polystyrene board is always present in the inverted flat roof, and although it is an unbeatable product for this use, it presents incompatibilities and interactions with other materials, and these can affect their properties and therefore the durability of them.La cubierta plana invertida es un sistema constructivo muy utilizado en las cubiertas planas. En esta solución constructiva, el aislamiento se coloca sobre el material impermeabilizante a modo de protección. Se cree que esta solución proporciona un ciclo de vida más largo; dado que se limita la variación térmica de la impermeabilización hasta el final de su ciclo de vida. En consecuencia, el resultado proporciona una vida más larga a la membrana impermeable. Esta solución constructiva siempre incorpora polímeros u otros materiales con adición termoplástica en su composición. Algunos polímeros muestran interacciones entre ellos que pueden afectar a su integridad, además, la mayor parte de los materiales poliméricos son incompatibles. La plancha de poliestireno extrusionado está siempre presente en la cubierta plana invertida, y aunque es un producto inmejorable para este uso, presenta incompatibilidades e interacciones con otros

  14. Nanoscale Chemical Imaging of an Individual Catalyst Particle with Soft X-ray Ptychography

    OpenAIRE

    Wise, Anna M.; Weker, Johanna Nelson; Kalirai, Sam; Farmand, Maryam; Shapiro, David A.; MEIRER, FLORIAN; Weckhuysen, Bert M.

    2016-01-01

    Understanding Fe deposition in fluid catalytic cracking (FCC) catalysis is critical for the mitigation of catalyst degradation. Here we employ soft X-ray ptychography to determine at the nanoscale the distribution and chemical state of Fe in an aged FCC catalyst particle. We show that both particle swelling due to colloidal Fe deposition and Fe penetration into the matrix as a result of precracking of large organic molecules occur. The application of ptychography allowed us to provide direct ...

  15. Regeneration of Hydrotreating and FCC Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    CM Wai; JG Frye; JL Fulton; LE Bowman; LJ Silva; MA Gerber

    1999-09-30

    Hydrotreating, hydrocracking, and fluid catalytic cracking (FCC) catalysts are important components of petroleum refining processes. Hydrotreating and hydrocracking catalysts are used to improve the yield of high-quality light oil fractions from heavier crude oil and petroleum feedstocks containing high levels of impurities. FCC catalysts improve the yield of higher octane gasoline from crude oil. Residuum hydrotreating and cracking catalysts are susceptible to irreversible deactivation caused by adsorption of sulfur and by metals impurities, such as vanadium and nickel. The gradual buildup of these impurities in a hydrotreating catalyst eventually plugs the pores and deactivates it. Nickel and vanadium adversely affect the behavior of cracking catalysts, reducing product yield and quality. Replacing deactivated catalysts represents a significant cost in petroleum refining. Equally important are the costs and potential liabilities associated with treating and disposing spent catalysts. For example, recent US Environmental Protection Agency rulings have listed spent hydrotreating and hydrorefining catalysts as hazardous wastes. FCC catalysts, though more easily disposed of as road-base or as filler in asphalt and cement, are still an economic concern mainly because of the large volumes of spent catalysts generated. New processes are being considered to increase the useful life of catalysts or for meeting more stringent disposal requirements for spent catalysts containing metals. This report discusses a collaborative effort between Pacific Northwest National Laboratory (PNNL) and Phillips Petroleum, Inc., to identify promising chemical processes for removing metals adhered to spent hydrodesulfurization (HDS, a type of hydrotreating catalyst) and FCC catalysts. This study, conducted by PNNL, was funded by the US Department of Energy's Bartlesville Project Office. Fresh and spent catalysts were provided by Phillips Petroleum. The FCC catalyst was a rare

  16. Catalyst containing oxygen transport membrane

    Science.gov (United States)

    Christie, Gervase Maxwell; Wilson, Jamie Robyn; van Hassel, Bart Antonie

    2012-12-04

    A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a high average pore diameter and the intermediate porous layer has a lower permeability and lower pore diameter than the porous support layer. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

  17. Extruded whole grain diets based on brown, soaked and germinated rice. Effects on the lipid profile and antioxidant status of growing Wistar rats. Part II.

    Science.gov (United States)

    Albarracín, Micaela; Weisstaub, Adriana R; Zuleta, Angela; Drago, Silvina R

    2016-06-15

    The influence of whole grain (WG) rice based diets on the lipid profile and antioxidant status was evaluated. Thirty-two male Wistar rats were fed with Control (C), extruded Brown rice (B), extruded Soaked whole rice (S) and extruded Germinated whole rice (G) diets for 60 days. Triacylglycerols (TAGs), cholesterol and malondialdehyde equivalent (MDA eq.) in serum and liver were determined. Catalase (CAT), Glutathione Reductase (GR) and Glutathione Peroxidase (GPx) enzyme activities and Glutathione Reduced (GSH) and Oxidized (GSSG) in the liver were analyzed. Animals consuming B and S diets presented lower body weight gain. All WG diets reduced TAGs in serum and MDA eq. content in liver in comparison with the C diet. WG rice diets improved the redox status in animals mainly fed G due to their higher GR activity and GSH/GSSG ratio. PMID:27213275

  18. Optimization of light yield by injection of the optical filler into the co extruded hole of plastic scintillation bar with WLS fiber in it

    CERN Document Server

    Artikov, A; Budagov, Yu; Chokheli, D; Davydov, Yu; Glagolev, V; Kharzheev, Yu; Kolomoetz, V; Shalugin, A; Simonenko, A; Tereshchenko, V

    2016-01-01

    Results of the measurements with cosmic muons for the light yield of 2-meter long extruded scintillation bar (strip) as a function of distance for different options for light collection technique are presented. Scintillation strip cross section geometry was a triangle made on polystyrene plastic scintillator with dopants of 2% PTP and 0.03% POPOP, extruded with 2.6 mm diameter hole and produced at ISMA (Kharkov, Ukraine). It was shown that the insertion of the optical transparent resin (BC 600 or CKTN MED(E)) by special technique into the co-extruded hole with 1.0 mm or 1.2 mm wave-length shifter (WLS) fiber Kuraray Y11 (200) MC in it significantly improves light collection by factor of 1.6...1.9 against of the 'dry' case.

  19. Effects of processing moisture on the physical properties and in vitro digestibility of starch and protein in extruded brown rice and pinto bean composite flours.

    Science.gov (United States)

    Sumargo, Franklin; Gulati, Paridhi; Weier, Steven A; Clarke, Jennifer; Rose, Devin J

    2016-11-15

    The influence of pinto bean flour and processing moisture on the physical properties and in vitro digestibility of rice-bean extrudates has been investigated. Brown rice: pinto bean flour (0%, 15%, 30%, and 45% bean flour) were extruded under 5 moisture conditions (17.2%, 18.1%, 18.3%, 19.5%, and 20.1%). Physical properties [bulk density, unit density, radial expansion, axial expansion, overall expansion, specific volume, hardness, color, water solubility index, and water absorption index] and in vitro starch and protein digestibilities were determined. Increasing bean flour and processing moisture increased density and hardness while decreasing expansion. Rapidly digestible starch decreased and resistant starch increased as bean substitution and processing moisture increased. In vitro protein digestibility increased with increasing bean flour or with decreasing processing moisture. Incorporating bean flour into extruded snacks can negatively affect physical attributes (hardness, density, and expansion) while positively affecting in vitro starch (decrease) and protein (increase) digestibilities. PMID:27283689

  20. Catalyst for Decomposition of Nitrogen Oxides

    Science.gov (United States)

    Schryer, David R. (Inventor); Jordan, Jeffrey D. (Inventor); Akyurtlu, Ates (Inventor); Akyurtlu, Jale (Inventor)

    2015-01-01

    This invention relates generally to a platinized tin oxide-based catalyst. It relates particularly to an improved platinized tin oxide-based catalyst able to decompose nitric oxide to nitrogen and oxygen without the necessity of a reducing gas.

  1. Use of lanthanide catalysts in air electrodes

    International Nuclear Information System (INIS)

    A review on the lanthanide catalysts suitable for the reduction catalysis of oxygen in air electrodes is presented. The kinds of lanthanide indicated to be used as catalysts of oxygen reduction are shown. (A.R.H.)

  2. Novel Fischer-Tropsch catalysts. [DOE patent

    Science.gov (United States)

    Vollhardt, K.P.C.; Perkins, P.

    Novel compounds are described which are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO + H/sub 2/ to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

  3. Biomass processing over gold catalysts

    CERN Document Server

    Simakova, Olga A; Murzin, Dmitry Yu

    2013-01-01

    The book describes the valorization of biomass-derived compounds over gold catalysts. Since biomass is a rich renewable feedstock for diverse platform molecules, including those currently derived from petroleum, the interest in various transformation routes has become intense. Catalytic conversion of biomass is one of the main approaches to improving the economic viability of biorefineries.  In addition, Gold catalysts were found to have outstanding activity and selectivity in many key reactions. This book collects information about transformations of the most promising and important compounds

  4. Rhenium Nanochemistry for Catalyst Preparation

    Directory of Open Access Journals (Sweden)

    Vadim G. Kessler

    2012-08-01

    Full Text Available The review presents synthetic approaches to modern rhenium-based catalysts. Creation of an active center is considered as a process of obtaining a nanoparticle or a molecule, immobilized within a matrix of the substrate. Selective chemical routes to preparation of particles of rhenium alloys, rhenium oxides and the molecules of alkyltrioxorhenium, and their insertion into porous structure of zeolites, ordered mesoporous MCM matrices, anodic mesoporous alumina, and porous transition metal oxides are considered. Structure-property relationships are traced for these catalysts in relation to such processes as alkylation and isomerization, olefin metathesis, selective oxidation of olefins, methanol to formaldehyde conversion, etc.

  5. Quick Guide to Flash Catalyst

    CERN Document Server

    Elmansy, Rafiq

    2011-01-01

    How do you transform user interface designs created in Photoshop or Illustrator into interactive web pages? It's easier than you think. This guide shows you how to use Adobe Flash Catalyst to create interactive UIs and website wireframes for Rich Internet Applications-without writing a single line of code. Ideal for web designers, this book introduces Flash Catalyst basics with detailed step-by-step instructions and screenshots that illustrate every part of the process. You'll learn hands-on how to turn your static design or artwork into working user interfaces that can be implemented in Fla

  6. OPTIMIZATION OF ALKALI, BIG BLUESTEM PARTICLE SIZE, AND EXTRUDER PARAMETERS FOR MAXIMUM ENZYMATIC SUGAR RECOVERY USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Chinnadurai Karunanithy

    2011-02-01

    Full Text Available Extrusion can be a viable continuous biomass pretreatment that industry can adopt readily due to its uniqueness (including pretreatment time less than 90 s over other pretreatment methods. The current study was undertaken to evaluate the combined effect of alkali soaking and extrusion of big bluestem to improve the sugar recovery to nearly quantitative. In order to evaluate the combined effect of alkali soaking and extrusion on the performance of enzymatic saccharification, big bluestem (2-10 mm was soaked in different alkali concentrations (0.5-2.5 % w/v NaOH for 30 min at room temperature and then extruded using a lab scale single screw extruder at various barrel temperatures (45-225°C and screw speeds (20-200 rpm. Statistical analyses confirmed that all the independent variables considered had a significant effect on sugar recovery. A proposed quadratic model to predict sugar recovery had high F and R2 values with a low p value, and adequately represented the relationship among the independent variables on sugar recovery. The optimum pretreatment condition found was the following: 90°C barrel temperature, 155 rpm screw speed, 2.0% alkali concentration, and 4 mm particle size resulted the maximum glucose, xylose, and combined sugar recovery of 90.1, 91.5, and 89.9%, respectively.

  7. Processing and characterization of extruded PET and its r-PET and MWCNT nanocomposite thin films by spin coating

    Indian Academy of Sciences (India)

    Arvind R Singh; Vineeta D Deshpande

    2016-02-01

    The objective of the present study was basic understanding of the formation of thin film morphology by spin coating using reorganized polyethylene terephthalate (r-PET) and multiwalled carbon nanotubes (MWCNTs) as fillers in PET. A study of the correlation between physical properties of the PET films and its surface morphology was carried out using atomic force microscopy-based power spectral density (PSD) analysis. No significant work of surface analysis, using PSD of thin films of PET has been reported till date. Dilute solution of PET, PET with 3 wt% (r-PET) and PET with 3 wt% (2 wt% r-PET + 1 wt% MWCNT) filler were prepared using trifluoroacetic acid (TFA) as a solvent and thin films were fabricated on glass substrate by the optimized spin coating technique. Preparation of r-PET and r-PET+ MWCNT fillers was obtained by the precipitation method using TFA as a solvent and acetone as an antisolvent. The samples before spin coating were extruded and for comparison, a film of non-extruded PET was also prepared. Structural studies by Fourier transform infrared and X-ray diffraction show higher degree of crystallinity in r-PET and decrease in chain entanglements. Owing to the crystallizing behaviour of r-PET, it allows better dispersion of MWCNT in the polymer matrix as compared with PET. The samples with fillers of MWCNT show more compact and unique mesh-like globular structure, indicating application for electromagnetic shielding foams and fibres.

  8. Low Temperature Creep of Hot-Extruded Near-Stoichiometric NiTi Shape Memory Alloy. Part I; Isothermal Creep

    Science.gov (United States)

    Raj, S. V.; Noebe, R. D.

    2013-01-01

    This two-part paper is the first published report on the long term, low temperature creep of hot-extruded near-stoichiometric NiTi. Constant load tensile creep tests were conducted on hot-extruded near-stoichiometric NiTi at 300, 373 and 473 K under initial applied stresses varying between 200 and 350 MPa as long as 15 months. These temperatures corresponded to the martensitic, two-phase and austenitic phase regions, respectively. Normal primary creep lasting several months was observed under all conditions indicating dislocation activity. Although steady-state creep was not observed under these conditions, the estimated creep rates varied between 10(exp -10) and 10(exp -9)/s. The creep behavior of the two phases showed significant differences. The martensitic phase exhibited a large strain on loading followed by a primary creep region accumulating a small amount of strain over a period of several months. The loading strain was attributed to the detwinning of the martensitic phase whereas the subsequent strain accumulation was attributed to dislocation glide-controlled creep. An "incubation period" was observed before the occurrence of detwinning. In contrast, the austenitic phase exhibited a relatively smaller loading strain followed by a primary creep region, where the creep strain continued to increase over several months. It is concluded that the creep of the austenitic phase occurs by a dislocation glide-controlled creep mechanism as well as by the nucleation and growth of deformation twins.

  9. Laboratory performance testing of an extruded bitumen containing a surrogate, sodium nitrate-based, low-level aqueous waste

    International Nuclear Information System (INIS)

    Laboratory results of a comprehensive regulatory performance test program, using an extruded bitumen and a surrogate, sodium nitrate-based waste, have been compiled at the Oak Ridge National Laboratory (ORNL). The testing has shown that the relatively viscous form of oxidized bitumen that was used has been able to meet all performance requirements. Using a 53-mm Werner and Pfleiderer extruder, operated by personnel of WasteChem Corporation of Paramus, New Jersey, laboratory-scale, molded samples of ASTM D312, type III, air-blown bitumen were prepared for laboratory performance testing. A surrogate, low-level, mixed liquid waste, formulated to represent an actual on-site waste at ORNL, was used. The mixed liquid waste contained approximately 30 wt % sodium nitrate, in addition to eight heavy metals, cold cesium, and strontium. Samples tested contained three levels of waste loading: that is, 40, 50, and 60 wt % salt. Performance test results include the 90-day American Nuclear Society (ANS) 16.1 leach test, with leach indices reported for all cations and anions, in addition to the EP toxicity test, at all levels of waste loading. Additionally, test results presented include the unconfined compressive strength and surface morphology utilizing scanning electron microscopy (SEM). Data presented include correlations between waste form loading and test results, in addition to their relationship to regulatory performance requirements

  10. Compostability of Co-Extruded Starch/Poly(Lactic Acid Polymeric Material Degradation in an Activated Inert Solid Medium

    Directory of Open Access Journals (Sweden)

    Alain Copinet

    2009-07-01

    Full Text Available The aim of this work was to estimate the biodegradation of a co-extruded starch/poly(lactic acid polymeric material using a vermiculite based inert solid medium which could simulate compost medium and enable us to achieve complete carbon balances. At the end of the test the mineralisation rate was compared to those obtained for co-extruded starch/poly(lactic acid polymeric material degradation in compost. It was shown that the mineralisation rate after 45 days of degradation was similar in activated vermiculite medium to the one in compost. A protocol for both extraction and quantification of the carbon included in the different degradation by-products was proposed and the carbon balance of the polymer degradation was followed during the test with a satisfactory accuracy. As the non-degraded PLA and starch material had been retrieved during the test, the evolution of the glass transition temperature and the molecular weight of PLA could be followed. A two-step degradation mechanism was highlighted in inert solid medium, showing the fundamental role of abiotic reactions for PLA degradation in compost.

  11. Extruded Soluplus/SIM as an oral delivery system: characterization, interactions, in vitro and in vivo evaluations.

    Science.gov (United States)

    Zhang, Yuanyuan; Liu, Yuxin; Luo, Yanfei; Yao, Qing; Zhong, Yue; Tian, Bin; Tang, Xing

    2016-07-01

    The aim of this study was to obtain a stable, amorphous solid dispersion (SD) with Soluplus, prepared by hot-melt extrusion (HME) as an effective and stable oral delivery system to improve the physical stability and bioavailability of the poorly water-soluble simvastatin (SIM), a drug with relatively low Tg. The drug was proved to be miscible with Soluplus by calculation and measurements. The solubility, dissolution, thermal characteristics, interactions and physical stability of the SIM/Soluplus SDs were investigated. The crystal state of simvastatin in the SD was found to change from crystalline to amorphous form during the HME process and also hydrogen bonds were observed between SIM and the extruded Soluplus. The phase solubility showed the solubilization effect of Soluplus was strong and spontaneous. The equilibrium solubility illustrated that Soluplus/SIM SDs gained much higher solubility than its corresponding physical mixtures (PMs). Both of the dissolution profiles and in-vivo performance showed that the SIM/Soluplus SD obtained a marked enhancement, compared with the PM. There was a little change in the SIM/Soluplus SD during a 3-month storage period (40 °C, 75%), indicating the good physicochemical stability. The extruded Soluplus system prepared by HME is a good alternative for the water-insoluble SIM to improve the stability and bioavailability. PMID:25268150

  12. The use of blends of cassava flour and extruded full-fat soybeans in diets for broiler chickens.

    Science.gov (United States)

    Waldroup, P W; Ritchie, S J; Reese, G L; Ramsey, B E

    1984-09-01

    A study was conducted to determine the effects of blending different levels of a low-prussic acid cassava flour with extruded full-fat soybeans in diets for growing broiler chickens. The full-fat soybeans contribute oil which increases the energy content of the diet, aids in overcoming the dusty nature of cassava, and provide high-quality protein. One-third, two-thirds, and all of the maize was replaced by cassava in diets with none, 12.5 and 25% extruded full-fat soybeans. Diets were fed in pelleted form to broiler chickens for a 47-day feeding trial. Replacement of one-third of the maize with cassava had no adverse effects on body weight gains in this study with a reduction in weight at higher levels at the conclusion of the study. Feed utilization was reduced more severely than was anticipated. However, growth rate on the higher levels of cassava was reasonably good, indicating that producers might feed these diets for a slightly longer period of time and produce chickens more economically if cassava meal were available at a cost significantly less than that of maize. PMID:6544063

  13. Preparation, melting behavior and thermal stability of poly(lactic acid)/poly(propylene carbonate) blends processed by vane extruder

    Science.gov (United States)

    Zou, Wei; Chen, Rongyuan; Zhang, Haichen; Qu, Jinping

    2016-03-01

    Poly (lactic acid) (PLA)/Poly (propylene carbonate) (PPC) blends were prepared by vane extruder which is a type of novel polymer processing extruder based on elongation force field. Scanning electron microscope (SEM), differential scanning calorimetry (DSC) and thermogravimetric (TG) were used respectively to analyze the compatibility, the melting behavior and thermal stability properties of PLA/PPC blends affected by the different content of PPC. The results showed that with the increase of the PPC content, the glass transition temperature of PLA was reduced, and the glass transition temperature of PPC was increased, which indicated that PLA and PPC had partial compatibility. The cold crystallization temperature of PLA increased with the increase of the PPC content, which showed that PPC hindered the cold crystallization process of PLA. The addition of PPC had little impact on the melting process of PLA, and the melting temperature of PLA was almost kept the same value. Thermogravimetric analysis showed that the thermal stability of PPC was worse than that of PLA, the addition of PPC reduced the thermal stability of PLA.

  14. Colloidal nanoparticles as catalysts and catalyst precursors for nitrite hydrogenation

    NARCIS (Netherlands)

    Zhao, Yingnan

    2015-01-01

    The most distinguished advantage to use colloidal methods for catalyst preparation is that the size and the shape of nanoparticles can be manipulated easily under good control, which is normally difficult to achieve by using traditional methods, such as impregnation and precipitation. This facilitat

  15. Catalyst-assisted Probabilistic Entanglement Transformation

    OpenAIRE

    Feng, Yuan; Duan, Runyao; Ying, Mingsheng

    2004-01-01

    We are concerned with catalyst-assisted probabilistic entanglement transformations. A necessary and sufficient condition is presented under which there exist partial catalysts that can increase the maximal transforming probability of a given entanglement transformation. We also design an algorithm which leads to an efficient method for finding the most economical partial catalysts with minimal dimension. The mathematical structure of catalyst-assisted probabilistic transformation is carefully...

  16. Cotter's new plant diets on spent catalysts

    International Nuclear Information System (INIS)

    Cotter Corp.'s new 60-tpd spent-catalyst processing plant that recovers molybdenum, nickel, tungsten and vanadium products from spent catalysts is described. The company entered the business as a sideline to its main activity--the mining and processing of uranium ore. The spent-catalyst plant contains ammonium carbonate and sodium hydroxide leach circuits to provide the versatility required to recover various metals from a variety of spent catalysts

  17. Polymer-bound rhodium hydroformylation catalysts

    OpenAIRE

    Jongsma, Tjeerd

    1992-01-01

    Homogeneous catalysts are superior in activity, selectivity as well as specificity, but heterogeneous catalyst are often preferred in industrial processes, because of their good recoverability and their applicability in continuous flow reactors. It would be of great environmental, commercial and scientific interest to combine the advantages of both catalysts. A route to achieve this goal is to immobilize a potent homogeneous catalyst onto an insoluble resin. In this thesis we have used solubl...

  18. EFFECTS OF CATALYST MORPHOLOGY ON HYDROTREATING REACTIONS

    OpenAIRE

    TYE CHING THIAN

    2008-01-01

    Due to the new environmental regulations for fuel quality, refineries need to process cleaner fuel. This requires an improvement in performance of hydrotreating catalysts. Improvements in catalyst activity require knowledge of the relationships between catalyst morphology and activity. Molybdenum sulfide, the generally agreed catalysts that give the best performance in hydrocracking and hydrotreating was investigated for its morphology effects on hydrotreating reactions. Three types of MoS2 c...

  19. Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gangwal, S.; Jothimurugesan, K.

    1999-07-27

    A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption process, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gases from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or passivating the heavy metals on the spent FCC catalyst as an intermediate step.

  20. Attrition resistant catalysts and sorbents based on heavy metal poisoned FCC catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gangwal, Santosh (Cary, NC); Jothimurugesan, Kandaswamy (Hampton, VA)

    1999-01-01

    A heavy metal poisoned, spent FCC catalyst is treated by chemically impregnating the poisoned catalyst with a new catalytic metal or metal salt to provide an attrition resistant catalyst or sorbent for a different catalytic or absorption processes, such as catalysts for Fischer-Tropsh Synthesis, and sorbents for removal of sulfur gasses from fuel gases and flue-gases. The heavy metal contaminated FCC catalyst is directly used as a support for preparing catalysts having new catalytic properties and sorbents having new sorbent properties, without removing or "passivating" the heavy metals on the spent FCC catalyst as an intermediate step.

  1. Catalysts for portable, solid state hydrogen genration systems

    Science.gov (United States)

    Gabl, Jason Robert

    Hydrogen and air powered proton exchange membrane fuel cells are a potential alternative to batteries. In portable power systems, the design requirements often focus on cost efficiency, energy density, storability, as well as safety. Ammonia borane (AB), a chemical hydride containing 19.6 wt. % hydrogen, has a high hydrogen capacity and is a stable and non-toxic candidate for storing hydrogen in portable systems. Throughout this work, Department of Energy guidelines for low power portable hydrogen power systems were used as a baseline and comparison with commercially available systems. In order to make this comparison, the system parameters of a system using AB hydrolysis were estimated by developing capacity and cost correlations from the commercial systems and applying them to this work. Supporting experiments were designed to evaluate a system that would use a premixed solid storage bed of AB and a catalyst. This configuration would only require a user input of water in order to initiate the hydrogen production. Using ammonia borane hydrolysis, the hydrogen yield is ˜9 wt. %, when all reactants are considered. In addition to the simplicity of initiating the reaction, hydrolysis of AB has the advantage of suppressing the production of some toxic borazines that are present when AB is thermally decomposed. However, ammonia gas will be formed and this problem must be addressed, as ammonia is damaging to PEM fuel cells. The catalyst focused on throughout this work was Amberlyst - 15; an ion exchange resin with an acid capacity of 4.7 eq/kg and ammonia adsorbent. At less than 0.30/g, this is a cost effective alternative to precious metal catalysts. The testing with this catalyst was compared to a traditional catalyst in literature, 20% platinum in carbon, costing more than 40/g. The Amberlyst catalyst was found to reduce the formation of ammonia in the gas products from ˜3.71 wt. % with the Pt/C catalyst to 90 % to < 30 % over a 70 day aging study. This results

  2. CO and C3H8 total oxidation over Pd/La-Al2O3 catalysts:Effect of calcination temperature and hydrothermal treatment

    Institute of Scientific and Technical Information of China (English)

    周仁美; 邢丰; 王树元; 鲁继青; 金凌云; 罗孟飞

    2014-01-01

    A series of Pd/La-Al2O3 (PLA) catalysts with La-Al2O3 (LA) support calcined at different temperatures (500, 700, 900 and 1050 ºC) were prepared using an incipient wetness impregnation method. The activity of the fresh and hydrothermally aged PLA catalysts were tested for total oxidation of CO and C3H8. The activity of the fresh PLA catalysts for CO and C3H8 oxidation increased with increasing calcination temperature of the support, while the activities of the aged catalysts declined and became essentially the same. CO chemisorption results revealed that the suppressed activities of the aged catalysts were mainly due to the decline of palla-dium dispersion. The turnover frequency (TOF) of CO oxidation increased with increasing reduction ability of the catalysts, with a fresh catalyst calcined at 1050 ºC having the highest value (0.048 s-1). However, the TOF of C3H8 total oxidation was affected by not only the redox properties of catalysts but also the size of Pd particle, and large Pd particles possessed higher TOF value of C3H8 oxi-dation, with the highest value (0.125 s-1) being obtained on an aged catalyst calcined at 500 ºC.

  3. Alternative alkali resistant deNOx catalysts

    DEFF Research Database (Denmark)

    Putluru, Siva Sankar Reddy; Kristensen, Steffen Buus; Due-Hansen, Johannes;

    2012-01-01

    Alternative alkali resistant deNOx catalysts were prepared using three different supports ZrO2, TiO2 and Mordenite zeolite. The majority of the catalysts were prepared by incipient wetness impregnation of a commercial support, with vanadium, copper or iron precursor, one catalyst was prepared by...

  4. deNOx catalysts for biomass combustion

    DEFF Research Database (Denmark)

    Kristensen, Steffen Buus

    , however the alkali in biomass complicate matters. Alkali in biomass severely deactivates the catalyst used for the selective catalytic reduction in matter of weeks, hence a more alkali resistant catalyst is needed. In the thesis a solution to the problem is presented, the nano particle deNOx catalyst...

  5. Silver doped catalysts for treatment of exhaust

    Energy Technology Data Exchange (ETDEWEB)

    Park, Paul Worn (Peoria, IL); Hester, Virgil Raymond (Edelstein, IL); Ragle, Christie Susan (Havana, IL); Boyer, Carrie L. (Shiloh, IL)

    2009-06-02

    A method of making an exhaust treatment element includes washcoating a substrate with a slurry that includes a catalyst support material. At least some of the catalyst support material from the slurry may be transferred to the substrate, and silver metal (Ag) is dispersed within the catalyst support material.

  6. Catalyst for selective oxidation of hydrocarbons

    OpenAIRE

    Álvaro Rodríguez, Mercedes; Amarajothi, Dhakshinamoorthy; García Gómez, Hermenegildo

    2010-01-01

    [EN] The present invention relates to a solid catalyst that includes a metal-organic reticular pattem and an agent promoting the generation of radicals, to a method for obtaining said catalyst and to the use thereof as a catalyst in the selective aerobic oxidation reaction ofhydrocarbons.

  7. Efficient epoxidation of propene using molecular catalysts

    DEFF Research Database (Denmark)

    Markovits, Iulius I. E.; Anthofer, Michael H.; Kolding, Helene; Cokoja, Mirza; Pöthig, Alexander; Raba, Andreas; Herrmann, Wolfgang A.; Fehrmann, Rasmus; Kühn, Fritz E.

    2014-01-01

    The epoxidation of propene is performed in homogeneous phase using various molecular catalysts and H2O2 or tert-butyl hydroperoxide as oxidants. A comparison between some molybdenum catalysts and methyltrioxorhenium (MTO) shows that the well known Re catalyst is the best among the examined...

  8. 挤塑板和苯板在高寒地区应用分析%Application of Extruded Sheet and Benzene Board in Extremely Cold Areas

    Institute of Scientific and Technical Information of China (English)

    郑江龙

    2011-01-01

    挤塑板与苯板保温系统相似,挤塑板具有极佳的保温性能、出色的抗压性能、极低的吸水率、良好的隔音稳定性、超长的耐久性能、较好的尺寸稳定性及抗蠕变性能.%Thermal insulation system of extruded sheet is similar to benzene board. Extruded sheet has excellent insulation properties, excellent compression performance, low water absorption, good noise stability, long durability, good dimensional stability and creep resistance.

  9. Soot oxidation over NOx storage catalysts. Activity and deactivation

    International Nuclear Information System (INIS)

    Soot oxidation activity and deactivation of NOx storage and reduction (NSR) catalysts containing Pt, K, and Ba supported on Al2O3, are studied under a variety of reaction conditions. K-containing catalysts decrease soot oxidation temperature with O2 alone and the presence of Pt further enhance the activity due to synergetic effect. The active species responsible for synergism on Pt/K-Al2O3 are unstable and cannot be regenerated. Soot oxidation temperature decreases by about 150oC with NO+O2 exhaust feed gas and under lean conditions NSR system acts as catalysed soot filter (CSF). The reactions that are mainly responsible for decreasing soot oxidation temperature are: (1) soot oxidation with NO2 followed by NO recycles to NO2, and (2) soot oxidation with O2 assisted by NO2. Only a part of the stored NOx that is decomposed at high temperatures under lean conditions is found to be useful for soot oxidation. NOx storage capacity of NSR catalysts decreases upon ageing under soot oxidising conditions. This will lead to a decreased soot oxidation activity on stored nitrate decomposition. Pt/K-Al2O3 catalyst is more active, but least stable compared with Pt/Ba-Al2O3. (author)

  10. Aging Skin

    Science.gov (United States)

    ... email address Submit Home > Healthy Aging > Wellness Healthy Aging Aging skin More information on aging skin When it ... treated early. Return to top More information on Aging skin Read more from womenshealth.gov Varicose Veins ...

  11. Perovskite catalysts for oxidative coupling

    Science.gov (United States)

    Campbell, Kenneth D.

    1991-01-01

    Perovskites of the structure A.sub.2 B.sub.2 C.sub.3 O.sub.10 are useful as catalysts for the oxidative coupling of lower alkane to heavier hydrocarbons. A is alkali metal; B is lanthanide or lanthanum, cerium, neodymium, samarium, praseodymium, gadolinium or dysprosium; and C is titanium.

  12. Biodiesel production using heterogenous catalyst

    Science.gov (United States)

    The current transesterification of triacylglycerides (TAG) to produce biodiesel is based on the homogenous catalyst method using strong base such as hydroxides or methoxides. However, this method results in a number of problems: (1) acid pre-treatment is required of feedstocks high in free fatty ac...

  13. Toward Molecular Catalysts by Computer

    Energy Technology Data Exchange (ETDEWEB)

    Raugei, Simone; DuBois, Daniel L.; Rousseau, Roger J.; Chen, Shentan; Ho, Ming-Hsun; Bullock, R. Morris; Dupuis, Michel

    2015-02-17

    Rational design of molecular catalysts requires a systematic approach to designing ligands with specific functionality and precisely tailored electronic and steric properties. It then becomes possible to devise computer protocols to predict accurately the required properties and ultimately to design catalysts by computer. In this account we first review how thermodynamic properties such as oxidation-reduction potentials (E0), acidities (pKa), and hydride donor abilities (ΔGH-) form the basis for a systematic design of molecular catalysts for reactions that are critical for a secure energy future (hydrogen evolution and oxidation, oxygen and nitrogen reduction, and carbon dioxide reduction). We highlight how density functional theory allows us to determine and predict these properties within “chemical” accuracy (~ 0.06 eV for redox potentials, ~ 1 pKa unit for pKa values, and ~ 1.5 kcal/mol for hydricities). These quantities determine free energy maps and profiles associated with catalytic cycles, i.e. the relative energies of intermediates, and help us distinguish between desirable and high-energy pathways and mechanisms. Good catalysts have flat profiles that avoid high activation barriers due to low and high energy intermediates. We illustrate how the criterion of a flat energy profile lends itself to the prediction of design points by computer for optimum catalysts. This research was carried out in the Center for Molecular Electro-catalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences. Pacific Northwest National Laboratory (PNNL) is operated for the DOE by Battelle.

  14. 40Ar-39Ar age of a lava flow from the Bhimashankar Formation, Giravali Ghat, Deccan Traps

    Indian Academy of Sciences (India)

    Kanchan Pande; S K Pattanayak; K V Subbarao; P Navaneethakrishnan; T R Venkatesan

    2004-12-01

    We report here a 40Ar-39Ar age of 66.0 ± 0.9Ma (2 ) for a reversely magnetised tholeiitic lava flow from the Bhimashankar Formation (Fm.), Giravali Ghat, western Deccan province, India. This age is consistent with the view that the 1.8–2km thick bottom part of the exposed basalt flow sequence in the Western Ghats was extruded very close to 67.4 Ma.

  15. HARDNESS VERSUS TIME DEPENDENCY DURING ARTIFICIAL AGEING OF AlMgSi0.5 ALUMINIUM ALLOY

    OpenAIRE

    Mimica, Ratko

    2015-01-01

    Al-Mg-Si aluminium alloy are characterized by excellent deformability, but mechanical properties are not significant in extruded state. Improvement of mechanical properties is achieved by heat treatment, a process which allows formation of metastable precipitates during subsequent ageing. In this work, hardness versus time dependency for artificially aged AlMgSi0.5 (EN AW-6060) aluminium alloy at 185°C is presented, along with qualitative and quantitative analysis of results.

  16. Improved Catalysts for Heavy Oil Upgrading Based on Zeolite Y Nanoparticles Encapsulated Stable Nanoporous Host

    Energy Technology Data Exchange (ETDEWEB)

    Conrad Ingram; Mark Mitchell

    2006-09-30

    The addition of hydrothermally-aged zeolite Y precursor to an SBA-15 synthesis mixture under a mildly acidic condition resulted in the formation of mesoporous aluminosilicate catalyst, Al-SBA-15, containing strong Broensted acid sites and aluminum (Al) stabilized in a totally tetrahedral coordination. The physicochemical characteristics of the catalyst varied as a function of the synthesis conditions. The catalyst possessed surface areas ranging between 690 and 850 m{sup 2}/g, pore sizes ranging from 5.6 to 7.5 nm, and pore volumes up 1.03 cm{sup 3}, which were comparable to the parent SBA-15 synthesized under similar conditions. Two wt% Al was present in the catalyst that was obtained from the reaction mixture that contained the highest Al content. The Al remained stable in totally tetrahedral coordination after calcination at 550 C. The Al-SBA-15 mesoporous catalyst showed significant catalytic activity for cumene dealkylation, and the activity increased as the amount of zeolite precursor added to the SBA-15 mixture was increased. In preparation for the final phase of the project, the catalyst was embedded into psuedoboemite alumina (catapal B) matrix and then formed into pellets. In the final phase of the project, the pelletized catalyst will be evaluated for the conversion of heavy petroleum feedstocks to naphtha and middle distillates.

  17. Hydroprocessing using regenerated spent heavy hydrocarbon catalyst

    International Nuclear Information System (INIS)

    This patent describes a process for hydroprocessing a hydrocarbon feedstock. It comprises: contacting the feedstock with hydrogen under hydroprocessing conditions with a hydroprocessing catalyst wherein the hydroprocessing catalyst contains a total contaminant metals build-up of greater than about 4 wt. % nickel plus vanadium, a hydrogenation component selected from the group consisting of Group VIB metals and Group VIII metals and is regenerated spent hydroprocessing catalyst regenerated by a process comprising the steps: partially decoking the spent catalyst in an initial coke-burning step; impregnating the partially decoked catalyst with a Group IIA metal-containing impregnation solution; and decoking the impregnated catalyst in a final coke-burning step wherein the impregnated catalyst is contacted with an oxygen-containing gas at a temperature of about 600 degrees F to about 1400 degrees F

  18. Autothermal reforming catalyst having perovskite structure

    Science.gov (United States)

    Krumpel, Michael; Liu, Di-Jia

    2009-03-24

    The invention addressed two critical issues in fuel processing for fuel cell application, i.e. catalyst cost and operating stability. The existing state-of-the-art fuel reforming catalyst uses Rh and platinum supported over refractory oxide which add significant cost to the fuel cell system. Supported metals agglomerate under elevated temperature during reforming and decrease the catalyst activity. The catalyst is a perovskite oxide or a Ruddlesden-Popper type oxide containing rare-earth elements, catalytically active firs row transition metal elements, and stabilizing elements, such that the catalyst is a single phase in high temperature oxidizing conditions and maintains a primarily perovskite or Ruddlesden-Popper structure under high temperature reducing conditions. The catalyst can also contain alkaline earth dopants, which enhance the catalytic activity of the catalyst, but do not compromise the stability of the perovskite structure.

  19. Constitutive behavior and microstructure evolution of the as-extruded AE21 magnesium alloy during hot compression testing

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L.-X. [Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Fang, G., E-mail: fangg@tsinghua.edu.cn [Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Leeflang, M.A.; Duszczyk, J.; Zhou, J. [Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft (Netherlands)

    2015-02-15

    Highlights: • Constitutive equation of magnesium alloy AE21 for hot deformation is established. • Material processing history affects the activation energy for deformation. • Zener-Hollomon parameter is used to distinguish the shapes of flow stress curves. • Kink band plays an important role in causing a concave shape of the flow curve of AE21. - Abstract: Magnesium alloys containing rare earth elements possess improved corrosion resistance and mechanical properties and therefore have great potential for a wide range of applications including biomedical applications. Hot forming is meant not only for shaping but also for microstructure modification and performance enhancement. It is of great importance to define optimum forming conditions on the basis of a fundamental understanding of the response of magnesium alloys to deformation. The present study aimed at characterizing the hot deformation behavior of the as-extruded AE21 magnesium alloy by performing isothermal compression tests over a temperature range of 350-480 °C and a strain rate range of 0.001-10 s{sup -1}. Flow stress data obtained were intended for establishing a constitutive equation, which would be indispensable for the prediction of the response of the material to hot deformation, for example, by means of numerical simulation. The true stress-strain curves obtained from the experiments were analyzed, considering different mechanisms of microstructure evolution operating during compression testing at different stages. The Sellar and Tegart model was used to establish the constitutive equation of the alloy during the steady-state deformation. The differences in activation energy value between the present as-extruded magnesium alloy and other wrought magnesium alloys were found and attributed to materials processing history. The Zener-Hollomon parameter was used to correlate the deformation condition with the response of the material to deformation, reflected in the shape of the true stress

  20. Effect of feeding extruded flaxseed with different grains on the performance of dairy cows and milk fatty acid profile.

    Science.gov (United States)

    Neveu, C; Baurhoo, B; Mustafa, A

    2014-03-01

    Sixteen Holsteins cows were used in a Latin square design experiment to determine the effects of extruded flaxseed (EF) supplementation and grain source (i.e., corn vs. barley) on performance of dairy cows. Extruded flaxseed diets contained 10% [dry matter (DM) basis] of an EF product that consisted of 75% flaxseed and 25% ground alfalfa meal. Four lactating Holsteins cows fitted with rumen fistulas were used to determine the effects of dietary treatments on ruminal fermentation. Intakes of DM (23.2 vs. 22.2 kg/d), crude protein (4.2 vs. 4.0 kg/d), and neutral detergent fiber (8.3 vs. 7.9 kg/d) were greater for cows fed EF diets than for cows fed diets without EF. Milk yield and composition were not affected by dietary treatments. However, 4% fat-corrected milk (30.5% vs. 29.6 kg/d) and solids-corrected milk (30.7 vs. 29.9 kg/d) were increased by EF supplementation. Ruminal pH and total volatile fatty acid concentration were not influenced by EF supplementation. However, feeding barley relative to corn increased molar proportions of acetate and butyrate and decreased that of propionate. Ruminal NH3-N was lower for cows fed barley than for cows fed corn. Milk fatty acid composition was altered by both grain source and EF supplementation. Cows fed EF produced milk with higher polyunsaturated and lower saturated fatty acid concentrations than cows fed diets without EF. Feeding EF or corn increased the milk concentration of C18:0, whereas that of C16:0 was decreased by EF supplementation only. Extruded flaxseed supplementation increased milk fat α-linolenic acid content by 60% and conjugated linoleic acid content by 29%. Feeding corn relative to barley increased milk conjugated linoleic acid by 29% but had no effect on milk α-linolenic concentration. Differences in animal performance and milk fatty acid composition were mainly due to EF supplementation, whereas differences in ruminal fermentation were mostly due to grain source. PMID:24418278

  1. Constitutive behavior and microstructure evolution of the as-extruded AE21 magnesium alloy during hot compression testing

    International Nuclear Information System (INIS)

    Highlights: • Constitutive equation of magnesium alloy AE21 for hot deformation is established. • Material processing history affects the activation energy for deformation. • Zener-Hollomon parameter is used to distinguish the shapes of flow stress curves. • Kink band plays an important role in causing a concave shape of the flow curve of AE21. - Abstract: Magnesium alloys containing rare earth elements possess improved corrosion resistance and mechanical properties and therefore have great potential for a wide range of applications including biomedical applications. Hot forming is meant not only for shaping but also for microstructure modification and performance enhancement. It is of great importance to define optimum forming conditions on the basis of a fundamental understanding of the response of magnesium alloys to deformation. The present study aimed at characterizing the hot deformation behavior of the as-extruded AE21 magnesium alloy by performing isothermal compression tests over a temperature range of 350-480 °C and a strain rate range of 0.001-10 s-1. Flow stress data obtained were intended for establishing a constitutive equation, which would be indispensable for the prediction of the response of the material to hot deformation, for example, by means of numerical simulation. The true stress-strain curves obtained from the experiments were analyzed, considering different mechanisms of microstructure evolution operating during compression testing at different stages. The Sellar and Tegart model was used to establish the constitutive equation of the alloy during the steady-state deformation. The differences in activation energy value between the present as-extruded magnesium alloy and other wrought magnesium alloys were found and attributed to materials processing history. The Zener-Hollomon parameter was used to correlate the deformation condition with the response of the material to deformation, reflected in the shape of the true stress

  2. Enhancing Thermal Conductivity of Mg-Sn Alloy Sheet by Cold Rolling and Aging

    Science.gov (United States)

    Huang, Qiuyan; Tang, Aitao; Ma, Shida; Pan, Hucheng; Song, Bo; Gao, Zhengyuan; Rashad, Muhammad; Pan, Fusheng

    2016-06-01

    In present work, effect of cold rolling and aging on thermal conductivity (TC) of the as-extruded Mg-2Sn alloy was studied. Experimental results revealed that TC of as-extruded sheet decreases to value of ~105.4 W/m/K after 18% reduction rolling. TC increases with increase in aging time and regains the highest value of 126 W/m/K. Enhanced TC of cold-rolled Mg-Sn alloys is attributed to the defects annihilation, residual stress release, and precipitations. The more pronounced rolling reduction would induce more second-phase precipitations, and thus TC of the 18% rolled alloy is larger than that of 5% rolled alloys. Texture is also an important factor affecting thermal conductivity of Mg alloys, and double-peak texture is not beneficial for thermal transportation. The result would shed light on the novel design of highly conductive Mg sheet.

  3. Enhancing Thermal Conductivity of Mg-Sn Alloy Sheet by Cold Rolling and Aging

    Science.gov (United States)

    Huang, Qiuyan; Tang, Aitao; Ma, Shida; Pan, Hucheng; Song, Bo; Gao, Zhengyuan; Rashad, Muhammad; Pan, Fusheng

    2016-05-01

    In present work, effect of cold rolling and aging on thermal conductivity (TC) of the as-extruded Mg-2Sn alloy was studied. Experimental results revealed that TC of as-extruded sheet decreases to value of ~105.4 W/m/K after 18% reduction rolling. TC increases with increase in aging time and regains the highest value of 126 W/m/K. Enhanced TC of cold-rolled Mg-Sn alloys is attributed to the defects annihilation, residual stress release, and precipitations. The more pronounced rolling reduction would induce more second-phase precipitations, and thus TC of the 18% rolled alloy is larger than that of 5% rolled alloys. Texture is also an important factor affecting thermal conductivity of Mg alloys, and double-peak texture is not beneficial for thermal transportation. The result would shed light on the novel design of highly conductive Mg sheet.

  4. Catalyst for Carbon Monoxide Oxidation

    Science.gov (United States)

    Davis, Patricia; Brown, Kenneth; VanNorman, John; Brown, David; Upchurch, Billy; Schryer, David; Miller, Irvin

    2010-01-01

    In many applications, it is highly desirable to operate a CO2 laser in a sealed condition, for in an open system the laser requires a continuous flow of laser gas to remove the dissociation products that occur in the discharge zone of the laser, in order to maintain a stable power output. This adds to the operating cost of the laser, and in airborne or space applications, it also adds to the weight penalty of the laser. In a sealed CO2 laser, a small amount of CO2 gas is decomposed in the electrical discharge zone into corresponding quantities of CO and O2. As the laser continues to operate, the concentration of CO2 decreases, while the concentrations of CO and O2 correspondingly increase. The increasing concentration of O2 reduces laser power, because O2 scavenges electrons in the electrical discharge, thereby causing arcing in the electric discharge and a loss of the energetic electrons required to boost CO2 molecules to lasing energy levels. As a result, laser power decreases rapidly. The primary object of this invention is to provide a catalyst that, by composition of matter alone, contains chemisorbed water within and upon its structure. Such bound moisture renders the catalyst highly active and very long-lived, such that only a small quantity of it needs to be used with a CO2 laser under ambient operating conditions. This object is achieved by a catalyst that consists essentially of about 1 to 40 percent by weight of one or more platinum group metals (Pt, Pd, Rh, Ir, Ru, Os, Pt being preferred); about 1 to 90 percent by weight of one or more oxides of reducible metals having multiple valence states (such as Sn, Ti, Mn, Cu, and Ce, with SnO2 being preferred); and about 1 to 90 percent by weight of a compound that can bind water to its structure (such as silica gel, calcium chloride, magnesium sulfate, hydrated alumina, and magnesium perchlorate, with silica gel being preferred). Especially beneficial results are obtained when platinum is present in the

  5. 多层共挤出薄膜技术的发展概况%Development of Multilayer Co-extruded Film Technology

    Institute of Scientific and Technical Information of China (English)

    谈述战; 程真真; 陈丽娜; 王梦媚; 王德禧

    2013-01-01

    多层共挤出薄膜技术是当前广泛应用的1种先进的高聚物复合薄膜加工成型方法,文章对近几十年来高聚物复合薄膜多层共挤出的试验发展以及多层共挤出技术装备的发展进行了回顾.多层共挤出薄膜技术的发展主要体现在复合共挤出机头结构的设计改进.介绍了多层共挤出薄膜技术的发展轨迹,从而为今后的研究和多层复合薄膜的产业化提供依据.%Multilayer co-extruded film technology was widely applied in an advanced polymer composite film forming.Polymer composite film multilayer co-extruded test development,multilayer co-extrusion technology and equipment development in recent decades were reviewed.Multilayer co-extruded film technology development was mainly embodied in the co-extrusion die structure design improvement.Through multilayer co-extruded film technology development path,a basis was provided for future research and industrialization of multilayer films.

  6. Accelerating process and catalyst development in reforming reactions with high throughput technologies under industrially relevant conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schunk, S.A.; Bollmann, G.; Froescher, A.; Kaiser, H.; Lange de Oliveira, A.; Roussiere, T.; Wasserschaff, G. [hte Aktiengesellschaft, Heidelberg (Germany); Domke, I. [BASF SE, Ludwigshafen (Germany)

    2010-12-30

    like ethane or propane are challenging compositions for hydrogen and syngas production as enhanced catalyst deactivation can be observed in a lot of cases. In our case study we will illustrate how the right choice of reaction conditions and new catalyst developments can open up alternative process options. (II) Reforming of higher carbon containing feed-stocks like ethanol or naphtha containing feeds are difficult to process as the feed-stocks are easily subject to cracking reactions and olefin formation does lead to enhanced coking and ageing of the catalyst. In this case study we intend to illustrate how alternative catalyst concepts and operation under suitable process conditions can lead to improved materials that can operate in reaction corridors of interest. (orig.)

  7. Relaxation of residual stresses in 20%SiCw/6061Al composite as-extruded at high temperature

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The residual stress in a 20%SiCw/6061Al composite as-extruded was investigated by using X-ray stress measurement method. It was found that, high residual stress existed in the composite and residual stress distribution in each direction are not uniform. Relaxation process of residual stress in the composite was dynamically measured during annealing at high temperature. It is verified that the relaxation of residual stress obeys the power law at high temperature. With the creep mechanism, the relaxation behavior of residual stresses at high temperature was analyzed. The results show that, the stress exponent and activation energy for stress relaxation of the composite are obviously higher than those of the matrix alloy.

  8. Cyclic fibre texture in hot extruded Ni{sub 50}Mn{sub 29}Ga{sub 21}

    Energy Technology Data Exchange (ETDEWEB)

    Chulist, Robert; Skrotzki, Werner; Oertel, Carl-Georg [Institut fuer Strukturphysik, Technische Universitaet Dresden, D-01062 Dresden (Germany); Boehm, Andrea [Fraunhofer-Institut fuer Werkzeugmaschinen und Umformtechnik, D-01187 Dresden (Germany); Brokmeier, Heinz-Guenter; Lippmann, Thomas [Institut fuer Werkstoffforschung, GKSS Forschungszentrum Geesthacht, D-21494 Geesthacht (Germany)

    2011-07-01

    The cyclic texture in polycrystalline Ni{sub 50}Mn{sub 29}Ga{sub 21} magnetic shape memory alloy fabricated by hot extrusion was investigated with high-energy synchrotron radiation, neutron diffraction and electron backscatter diffraction. Combination of these techniques reveals that the texture of the hot extruded sample is quite complex. It is composed of components related to the radial direction and rotated around the extrusion axis. Additionally, the dominant texture components change from the centre to the edge of the rod. The recrystallized grains contain a lot of twins with the trace of the twin boundaries preferentially aligned along the extrusion and radial direction showing the cyclic nature of the texture and microstructure, too. The results are discussed with respect to deformation mode, phase transformations, starting grain structure and texture.

  9. Melt-Mixing by Novel Pitched-Tip Kneading Disks in a co-rotating Twin-Screw Extruder

    CERN Document Server

    Nakayama, Yasuya; Shigeishi, Takashi; Tomiyama, Hideki; Kajiwara, Toshihisa

    2010-01-01

    Melt-mixing in twin-screw extruders is a key process for development of polymer composites, and quantification of mixing performance of kneading elements based on the physical process in them is a challenging problem. We discuss melt-mixing by novel kneading elements, called "pitched-tip kneading disk (ptKD)". Disk-stagger angle and tip angle are the main geometrical parameters of the ptKDs. We investigated four typical arrangements of the ptKDs, which are forwarding and backwarding disk-staggers combined with forwarding and backwarding tips, respectively. Numerical simulations under a certain feed rate and screw revolution speed were performed and mixing process was investigated by using Lagrangian statistics. It is found that the four types had different mixing characteristics, and their mixing processes were explained by a coupling effect of drag flow by disk staggering and pitched-tip and pressure flow, which is controlled by operational conditions.

  10. Investigation on corrosion behaviour of as-extruded near eutectic Al-Si-Mg alloy by neutral salt spray test

    Directory of Open Access Journals (Sweden)

    Wu Yuna

    2013-07-01

    Full Text Available In order to provide scientific basis for advanced applications of near eutectic Al-Si-Mg alloys as architectural profiles, a comparative study on the corrosion resistance of an as-extruded near eutectic Al-Si-Mg alloy and AA6063 aluminium alloy was carried out by means of neutral salt spray test. The corroded surfaces of the alloys were examined with optical microscopy and scanning electron microscope (SEM. Results show that the corrosion type of these two alloys is pitting corrosion. The number of corrosion pits in the AA6063 aluminium alloy is more than that in the near eutectic Al-Si-Mg alloy, but the pits in the latter alloy are much larger and deeper. Because the relatively low polarization resistance of the near eutectic alloy leads to poorer repassivation ability, autocatalytic acidification occurs once a pit forms. Thus, occluded corrosion cells are developed in this alloy.

  11. Experimental and theoretical investigation of solids conveying, melting and global behavior in self-wiping co-rotating twin screw extruders

    Science.gov (United States)

    Bawiskar, Santosh Shyam

    Modern self wiping co-rotating twin screw extruders are modular and starve fed. This leads to flow and conveying mechanisms that are different from the conventional flood fed single screw extruders. Since the mid 1980's, there have been many studies to model melt flow in different modules of the self wiping co-rotating twin screw extruder with varying degrees of complexity. On the other hand, the solids conveying and melting mechanisms in these machines have not received much attention. In this dissertation we describe a composite model for solids conveying, melting and melt flow in a modular co-rotating twin screw extruder. The solids conveying and melting mechanisms were first investigated by conducting flow visualization experiments. The solids conveying experiments were carried out by building transparent polymethyl methacrylate (PMMA) barrels and observing the pellet motions in the different elements of the self wiping co-rotating twin screw extruder. To understand the melting mechanisms several 'screw pull-out' experiments were conducted with various polymers under different operating conditions and using different screw configuration designs. The distribution of the polymer on the pulled screws was photographed. Subsequently polymer carcasses were stripped and cross-sectioned from the screws to study the progression of melting of solid pellets along the screw axis. Based on the experimental observations, new models for solids conveying and melting in modular self wiping co-rotating twin screw extruders were derived. These were then combined with the existing melt conveying models from our laboratories and the global performance of the self wiping co-rotating twin screw extruder was simulated. Computations were made for axial fill factor, pressure, temperature, melting profiles and also the power consumption, torque, specific energy consumption and average residence times. The simulation results were compared to experiments and were found to be in good

  12. Investigation of Aging Mechanisms in Lean NOx Traps

    Energy Technology Data Exchange (ETDEWEB)

    Mark Crocker

    2010-03-31

    Lean NO{sub x} traps (LNTs) represent a promising technology for the abatement of NO{sub x} under lean conditions. Although LNTs are starting to find commercial application, the issue of catalyst durability remains problematic. LNT susceptibility to sulfur poisoning is the single most important factor determining effective catalyst lifetime. The NO{sub x} storage element of the catalyst has a greater affinity for SO{sub 3} than it does for NO{sub 2}, and the resulting sulfate is more stable than the stored nitrate. Although this sulfate can be removed from the catalyst by means of high temperature treatment under rich conditions, the required conditions give rise to deactivation mechanisms such as precious metal sintering, total surface area loss, and solid state reactions between the various oxides present. The principle objective of this project was to improve understanding of the mechanisms of lean NO{sub x} trap aging, and to understand the effect of washcoat composition on catalyst aging characteristics. The approach utilized involved detailed characterization of model catalysts prior to and after aging, in tandem with measurement of catalyst performance in NO{sub x} storage and reduction. In this manner, NO{sub x} storage and reduction characteristics were correlated with the evolution of catalyst physico-chemical properties upon aging. Rather than using poorly characterized proprietary catalysts, or simple model catalysts of the Pt/BaO/Al{sub 2}O{sub 3} type (representing the first generation of LNTs), Pt/Rh/BaO/Al{sub 2}O{sub 3} catalysts were employed which also incorporated CeO{sub 2} or CeO{sub 2}-ZrO{sub 2}, representing a model system which more accurately reflects current LNT formulations. Catalysts were prepared in which the concentration of each of the main components was systematically varied: Pt (50, 75 or 100 g/ft{sup 3}), Rh (10 or 20 g/ft{sup 3}), BaO (15, 30 or 45 g/L), and either CeO{sub 2} (0, 50 or 100 g/L) or CeO{sub 2}-ZrO{sub 2} (0, 50

  13. Improved Catalysts for Heavy Oil Upgrading Based on Zeolite Y Nanoparticles Encapsulated Stable Nanoporous Host

    Energy Technology Data Exchange (ETDEWEB)

    Conrad Ingram; Mark Mitchell

    2007-03-31

    The addition of hydrothermally-aged zeolite Y precursor to an SBA-15 synthesis mixture under a mildly acidic condition resulted in the formation of a mesoporous aluminosilicate catalyst, AlSBA-15. The Al-SBA-15 mesoporous catalyst contains strong Br{umlt o}nsted acid sites and aluminum (Al) stabilized in a totally tetrahedral coordination. The physicochemical characteristics of the catalyst varied as a function of the synthesis conditions. The catalyst possessed surface areas ranging between 690 and 850 m{sup 2}/g, pore sizes ranging from 5.6 to 7.5 nm, and pore volumes up 1.03 cm{sup 3}, which were comparable to the parent SBA-15 synthesized under similar conditions. Two wt % Al was present in the catalyst that was obtained from the reaction mixture that contained the highest Al content. The Al remained stable in totally tetrahedral coordination after calcination at a temperature of 550 C. The Al-SBA-15 mesoporous catalyst showed significant catalytic activity for cumene dealkylation, and the activity increased as the amount of zeolite precursor added to the SBA-15 mixture was increased. In preparation for the final phase of the project, the catalyst was embedded into a psuedoboemite alumina (catapal B) matrix and then formed into pellets. In the final phase of the project, the pelletized catalyst is being evaluated for the conversion of a heavy petroleum feedstock to naphtha and middle distillates. This phase was significantly delayed during the past six months due to a serious malfunction of the fume hoods in the Clark Atlanta University's Research Center for Science and Technology, where the project is being conducted. The fume hood system was repaired and the catalyst evaluation is now underway.

  14. OXIDATION OF MERCURY ACROSS SCR CATALYSTS IN COAL-FIRED POWER PLANTS BURNING LOW RANK FUELS

    Energy Technology Data Exchange (ETDEWEB)

    Constance Senior; Temi Linjewile

    2003-10-31

    This is the third Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-03NT41728. The objective of this program is to measure the oxidation of mercury in flue gas across SCR catalyst in a coal-fired power plant burning low rank fuels using a slipstream reactor containing multiple commercial catalysts in parallel. The Electric Power Research Institute (EPRI) and Argillon GmbH are providing co-funding for this program. This program contains multiple tasks and good progress is being made on all fronts. During this quarter, the second set of mercury measurements was made after the catalysts had been exposed to flue gas for about 2,000 hours. There was good agreement between the Ontario Hydro measurements and the SCEM measurements. Carbon trap measurements of total mercury agreed fairly well with the SCEM. There did appear to be some loss of mercury in the sampling system toward the end of the sampling campaign. NO{sub x} reductions across the catalysts ranged from 60% to 88%. Loss of total mercury across the commercial catalysts was not observed, as it had been in the March/April test series. It is not clear whether this was due to aging of the catalyst or to changes in the sampling system made between March/April and August. In the presence of ammonia, the blank monolith showed no oxidation. Two of the commercial catalysts showed mercury oxidation that was comparable to that in the March/April series. The other three commercial catalysts showed a decrease in mercury oxidation relative to the March/April series. Oxidation of mercury increased without ammonia present. Transient experiments showed that when ammonia was turned on, mercury appeared to desorb from the catalyst, suggesting displacement of adsorbed mercury by the ammonia.

  15. Direct preparation of poly(L-lactic acid) by ring-opening polymerization of L-lactide using a twin-screw extruder%双螺杆法丙交酯直接反应挤出制备聚乳酸

    Institute of Scientific and Technical Information of China (English)

    吴剑波; 刘鹏; 李杨; 杨革生; 邵惠丽

    2012-01-01

    The poly(L-lactic acid) (PLLA) was rapidly synthesized from L-lactide (L-LA) by using 2-ethylhexanoic acid tin (Ⅱ) salt and triphenylphosphine as the catalyst system and using a twin-screw ex-truder as a reactor. The effects of the polymerization time, polymerization temperature, the screw speed and the catalyst content on polymer properties were investigated. The results showed that when the twin-screw speed was 110 r/min,the polymerization temperature was 170℃ ,the molar ratio of monomer/catalyst was 2 000 : 1 and the polymerization time was 1. 5 h, the PLLA polymer with a molecular weight of about 49 000 and optical purity of 93% could be obtained.%以L-丙交酯为原料,辛酸亚锡和三苯基膦为催化体系,利用双螺杆挤出机快速制备具有一定分子量的聚乳酸.研究了聚合时间、聚合温度、螺杆转速以及催化剂含量对聚合产物性质的影响.结果表明,在双螺杆转速110 r/min,聚合温度170℃,单体与催化剂摩尔比为2000:1条件下,聚合1.5h,能获得粘均分子量约为4.9万、光学纯度达到93%的聚乳酸.

  16. Preparation of poly(L-lactic acid) by using twin-screw extruder as a reactor%双螺杆反应挤出法开环聚合制备聚乳酸的研究

    Institute of Scientific and Technical Information of China (English)

    李杨; 刘鹏; 吴剑波; 杨革生; 邵惠丽; 胡学超

    2014-01-01

    Direct preparation of poly(L-lactic acid) (PLLA) by ring-opening polymerization of L-lactide using twin-screw extruder was carried out .The influence of the catalyst type and content , the polymerization temperature and the polymerization time on polymer properties were investigated .The results showed that the relative appropri-ate reaction conditions were as follows:2-ethylhexanoic acid tin ( II) salt was selected as the main catalyst and 1,do-decanol was selected as the cocatalyst , the polymerization temperature was 170℃, the molar ratio of monomer/cat-alyst was 3 000∶1 and the polymerization time was 120 min.Under the above conditions , the PLLA polymer with a molecular weight of about 5.3 ×104 could be obtained.The structure and thermal properties of polymer were char-acterized by FT-IR, 1 H-NMR, DSC and TG, etc.%以双螺杆挤出机为反应器来实施L-丙交酯的开环聚合制备聚乳酸,探讨了催化剂种类及其含量、聚合温度及聚合时间等因素对聚合产物性质的影响。实验获得的相对适宜的工艺条件如下:优选辛酸亚锡(Sn(Oct)2)/1-十二醇(CH3(CH2)11OH)为复合催化剂体系,单体与催化剂摩尔比为3000∶1,聚合温度为170℃,聚合时间为120 min,由此可获得粘均相对分子质量为5.3×104的聚(L-乳酸)。在此基础上,进一步采用 FT-IR、1H-NMR、DSC和 TG等分析手段对聚合产物的结构和热性能进行了表征。

  17. A Comparative Kinetics Study between Cu/SSZ-13 and Fe/SSZ-13 SCR Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Feng; Wang, Yilin; Kollar, Marton; Washton, Nancy M.; Szanyi, Janos; Peden, Charles HF

    2015-11-09

    Cu- and Fe/SSZ-13 catalysts with the same Cu(Fe)/Al ratios are synthesized using the same parent SSZ-13 starting material. The catalytic performance for both fresh and hydrothermally aged catalysts is tested with NO and NH3 oxidation, and standard SCR reactions under steady-state conditions, and standard and fast SCR under temperature-programmed conditions. For standard SCR, Cu/SSZ-13 shows much better low-temperature performance which can be explained by NH3-inhibition of Fe/SSZ-13. During hydrothermal aging, both catalysts undergo dealumination but Fe/SSZ-13 dealuminates more severely. For aged catalysts, Cu/SSZ-13 gains oxidation activities due to formation of CuOx. However, Fe/SSZ-13 loses oxidation activities although formation of FeOx clusters and FeAlOx species also occur. Because of such physical properties differences, aged Cu/SSZ-13 loses while Fe/SSZ-13 maintains high-temperature SCR selectivities. A physical mixture of aged catalysts provides stable SCR performance in a wide temperature range and is able to decrease N2O formation at high reaction temperatures. This suggests that Fe/SSZ-13 can be used as a cocatalyst for Cu/SSZ-13 for transportation applications. During temperature-programmed SCR reactions, weak hysteresis is found during standard SCR due to NH3 inhibition. For fast SCR, hysteresis caused by NH4NO3 inhibition is much more significant. NH4NO3 deposition is greatly enhanced by Brønsted and Lewis acidity of the catalysts.

  18. Optimization of catalyst system reaps economic benefits

    International Nuclear Information System (INIS)

    Champlin Refining and Chemicals Inc. is learning to optimize its catalyst systems for hydrotreating Venezuelan gas oils through a program of research, pilot plant testing, and commercial unit operation. The economic results of this project have been evaluated, and the benefits are most evident in improvements in product yields and qualities. The project has involved six commercial test runs, to date (Runs 10-15), with a seventh run planned. A summary of the different types of catalyst systems used in the test runs, and the catalyst philosophy that developed is given. Runs 10 and 11 used standard CoMo and NiMo catalysts for heavy gas oils hydrotreating. These catalysts had small pore sizes and suffered high deactivation rates because of metals contamination. When it was discovered that metals contamination was a problem, catalyst options were reviewed

  19. EFFECTS OF CATALYST MORPHOLOGY ON HYDROTREATING REACTIONS

    Directory of Open Access Journals (Sweden)

    TYE CHING THIAN

    2008-08-01

    Full Text Available Due to the new environmental regulations for fuel quality, refineries need to process cleaner fuel. This requires an improvement in performance of hydrotreating catalysts. Improvements in catalyst activity require knowledge of the relationships between catalyst morphology and activity. Molybdenum sulfide, the generally agreed catalysts that give the best performance in hydrocracking and hydrotreating was investigated for its morphology effects on hydrotreating reactions. Three types of MoS2 catalysts with different morphology were studied. They are crystalline MoS2, exfoliated MoS2 and MoS2 derived from a precursor, molybdenum naphthenate. Exfoliated MoS2 with minimal long range order, with much higher rim edges has shown relative higher hydrogenation activity. Generally, results of MoS2 catalyst activities in hydrogenation, hydrodesulfurization, hydrodenitrogenation and hydrideoxy¬gena¬tion are in agreement with the rim-edge model.

  20. Steam gasification of carbon: Catalyst properties

    Energy Technology Data Exchange (ETDEWEB)

    Falconer, J.L.

    1991-09-16

    This research uses several techniques to measure the concentration of catalyst sites and determine their stoichiometry for the catalyzed gasification of carbon. Both alkali and alkaline earth oxides are effective catalysts for accelerating the gasification rate of coal chars, but only a fraction of the catalyst appears to be in a form that is effective for gasification, and the composition of that catalyst is not established. Transient techniques, with {sup 13}C labeling, are being used to study the surface processes, to measure the concentration of active sites, and to determine the specific reaction rates. We have used secondary ion mass spectroscopy (SIMS) for both high surface area samples of carbon/alkali carbonate mixtures and for model carbon surfaces with deposited alkali atoms. SIMS provides a direct measure of surface combination of these results can provide knowledge of catalyst dispersion and composition, and thus indicate the way to optimally utilize carbon gasification catalysts.

  1. Nanoparticular metal oxide/anatase catalysts

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention concerns a method of preparation of nanoparticular metal oxide catalysts having a narrow particle size distribution. In particular, the invention concerns preparation of nanoparticular metal oxide catalyst precursors comprising combustible crystallization seeds upon which th...... nitrogen oxides with ammonia or urea as reductant, oxidations of alcohols or aldehydes with dioxygen or air to provide aldehydes, ketones or carboxylic acids, and photocatalytic oxidation of volatile organic compounds (VOCs).......The present invention concerns a method of preparation of nanoparticular metal oxide catalysts having a narrow particle size distribution. In particular, the invention concerns preparation of nanoparticular metal oxide catalyst precursors comprising combustible crystallization seeds upon which the...... catalyst metai oxide is co-precipitated with the carrier metal oxide, which crystallization seeds are removed by combustion in a final calcining step. The present invention also concerns processes wherein the nanoparticular metal oxide catalysts of the invention are used, such as SCR (deNOx) reactions of...

  2. Catalysts for decomposing ozone tail gas

    Institute of Scientific and Technical Information of China (English)

    LIU Chang-an; SUN De-zhi; WANG Hui; LI Wei

    2003-01-01

    The preparation of immobilizing-catalysts for decomposing ozone by using dipping method was studied. XRD, XPS and TEM were used to characterize the catalysts. The three kinds of catalysts were selected preferentially, and their catalytic activities were investigated. The results showed that the catalyst with activated carbon dipping acetate (active components are Mn: Cu = 3:2, active component proportion in catalyst is 15%, calcination temperature is 200℃ ) has the best catalytic activity for ozone decomposing. One gram of catalyst can decompose 17.6 g ozone at initial ozone concentration of 2.5 g/m3 and the residence time in reactor of 0.1 s. The experimental results also indicated that humidity of reaction system had negative effect on catalytic activity.

  3. Highly Selective Ruthenium Metathesis Catalysts for Ethenolysis

    OpenAIRE

    Thomas, Renee M.; Keitz, Benjamin K.; Champagne, Timothy M.; Grubbs, Robert H.

    2011-01-01

    N-aryl, N-alkyl N-heterocyclic carbene (NHC) ruthenium metathesis catalysts are highly selective toward the ethenolysis of methyl oleate, giving selectivity as high as 95% for the kinetic, ethenolysis products over the thermodynamic, self-metathesis products. The examples described herein represent some of the most selective NHC-based ruthenium catalysts for ethenolysis reactions to date. Furthermore, many of these catalysts show unusual preference and stability toward propagating as a methyl...

  4. Examining the surfaces in used platinum catalysts

    OpenAIRE

    Trumić B.; Stanković D.; Trujić V.

    2009-01-01

    For the purpose of finding more advanced platinum catalyst manufacturing technologies and achieving a higher degree of ammonia oxidation, metallographic characterization has been done on the surface of catalyst gauzes and catalyst gripper gauzes made from platinum and palladium alloys. For the examined samples of gauzes as well as the cross section of the wires, a chemical analysis was provided. The purpose of this paper is the metallographic characterization of examined alloys carried out by...

  5. Catalysts for Dehydrogenation of ammonia boranes

    Energy Technology Data Exchange (ETDEWEB)

    Heinekey, Dennis M.

    2014-12-19

    Several effective homogeneous catalysts for the dehydrogenation of amine boranes have been developed. The best catalyst uses an iridium complex, and is capable of dehydrogenating H3NBH3 (AB) and CH3NH2BH3 (MeAB) at comparable rates. Thermodynamic measurements using this catalyst demonstrate that the dehydrogenation of AB and MeAB is substantially exothermic, which has important implications for regeneration.

  6. Manufacture of Catalyst Systems for Ammonia Conversion

    Institute of Scientific and Technical Information of China (English)

    GAKH S.V.; SAVENKOV D.A.

    2012-01-01

    Platinum catalyst gauzes have been in use since the moment of development of the process of catalyst oxidation of ammonia for production of nitric acid or hydrocyanic acid.Catalyst gauzes are usually made of platinum or its alloys with rhodium and palladium.These precious metals have remarkable properties that make them ideal catalysts for acceleration of the ammonia/oxygen reaction.In 2008,OJSC "SIC ‘Supermetal’" and Umicore AG&Co.KG launched a production line for Pt-alloy-based catalyst systems to be used for ammonia oxidation in the production of weak nitric acid.Catalyst systems consist of a pack of catalyst gauzes and a pack of catchment gauzes,which are made using flat-bed knitting machines and wire-cloth looms.Today,up-to-date catalyst systems MKSpreciseTM are being manufactured,the basic advantages of which are an individual structure of gauzes and composition of the material,which allows to define precisely the position of each gauze in the catalyst pack,a high activity of the catalyst pack,direct catching of platinum and rhodium in the catalyst system,and a reasonable combination of single- and multilayer types of gauzes.This makes it possible to vary the configuration of the catalyst and select an optimum composition of the system to ensure the maximum efficiency of the ammonia oxidation process.We also produce the catchment systems that allow to find the best decision from the economic point view for each individual case.

  7. Thermally Stable, Latent Olefin Metathesis Catalysts

    OpenAIRE

    Thomas, Renee M.; Fedorov, Alexey; Keitz, Benjamin K.; Grubbs, Robert H.

    2011-01-01

    Highly thermally stable N-aryl,N-alkyl N-heterocyclic carbene (NHC) ruthenium catalysts were designed and synthesized for latent olefin metathesis. These catalysts showed excellent latent behavior toward metathesis reactions, whereby the complexes were inactive at ambient temperature and initiated at elevated temperatures, a challenging property to achieve with second generation catalysts. A sterically hindered N-tert-butyl substituent on the NHC ligand of the ruthenium complex was found to i...

  8. POLYMER-SUPPORTED LEWIS ACID CATALYSTS. VI. POLYSTYRENE-BONDED STANNIC CHLORIDE CATALYST

    Institute of Scientific and Technical Information of China (English)

    RAN Ruicheng; FU Diankui

    1991-01-01

    A polystyrene-bonded stannic chloride catalyst was synthesized by the method of lithium polystyryl combined with stannic chloride. This catalyst is a polymeric organometallic compound containing 0.25 mmol Sn(IV)/g catalyst. The catalyst showed sufficient stability and catalytic activity in organic reaction such as esterification, acetalation and ketal formation, and it could be reused many times without losing its catalytic activity.

  9. Effect of Sulfur on the Performance of Three-Way Catalysts

    Institute of Scientific and Technical Information of China (English)

    Li Yang; He Zhenfu; Shao Qian; Shen Ningyuan; Jing Zhenhua

    2003-01-01

    Sulfur content is one of the fuel properties to be monitored. Sulfur dioxide, the major product derived from organic sulfur compounds in the exhaust gas emissions, is a poison to the three-way catalysts (TWC). A gas mixture was applied to simulate the exhaust gases used in the TWC aging procedure tests. Two types of the TWC, REX-ⅡC and REX-ⅡD, were tested in this study. The performance of both TWC's before and after the 100-hour sulfur aging program was compared. It was concluded that the Pt component in the TWC was apt to be poisoned by sulfur much easily than Rh. The performance of the REX-ⅡD catalyst was generally better than that of the REX-ⅡC catalyst.

  10. Cationic ruthenium alkylidene catalysts bearing phosphine ligands

    OpenAIRE

    Endo, Koji; Grubbs, Robert H.

    2016-01-01

    The discovery of highly active catalysts and the success of ionic liquid immobilized systems have accelerated attention to a new class of cationic metathesis catalysts. We herein report the facile syntheses of cationic ruthenium catalysts bear-ing bulky phosphine ligands. Simple ligand exchange using silver(I) salts of non-coordinating or weakly coordinating anions pro-vided either PPh3 or chelating Ph2P(CH2)nPPh2 (n = 2 or 3) ligated cationic catalysts. The structures of these newly reported...

  11. Multidisciplinary determination of the phase distribution for VOX–ZrO2–SO42−–sepiolite catalysts for NH3-SCR

    DEFF Research Database (Denmark)

    Rasmussen, S.B.; Due-Hansen, Johannes; Villarroel, M.; Gil-Llambias, F.J.; Fehrmann, Rasmus; Ávila, P.

    2011-01-01

    A series of V2O5–ZrO2–SO42−–sepiolite mixtures were extruded, calcined and characterised. NH3-SCR activity was found to be related to the content of the active VOX–ZrO2–SO42− phase (VSZ). The distribution of sepiolite and VSZ at the surface of the mechanical mixtures was studied by the electropho......A series of V2O5–ZrO2–SO42−–sepiolite mixtures were extruded, calcined and characterised. NH3-SCR activity was found to be related to the content of the active VOX–ZrO2–SO42− phase (VSZ). The distribution of sepiolite and VSZ at the surface of the mechanical mixtures was studied by the...... results. Furthermore, it was verified by electrophoretic migration experiments that up until a composition of 75% VOX–ZrO2–SO42−, the sepiolite fibers coats the zirconia particles. This has a slightly negative influence on the overall SCR activity of fresh catalysts....

  12. Multidisciplinary determination of the phase distribution for VOX–ZrO2–SO42−–sepiolite catalysts for NH3-SCR

    DEFF Research Database (Denmark)

    Rasmussen, S.B.; Due-Hansen, Johannes; Villarroel, M.;

    2011-01-01

    A series of V2O5–ZrO2–SO42−–sepiolite mixtures were extruded, calcined and characterised. NH3-SCR activity was found to be related to the content of the active VOX–ZrO2–SO42− phase (VSZ). The distribution of sepiolite and VSZ at the surface of the mechanical mixtures was studied by the electropho......A series of V2O5–ZrO2–SO42−–sepiolite mixtures were extruded, calcined and characterised. NH3-SCR activity was found to be related to the content of the active VOX–ZrO2–SO42− phase (VSZ). The distribution of sepiolite and VSZ at the surface of the mechanical mixtures was studied...... results. Furthermore, it was verified by electrophoretic migration experiments that up until a composition of 75% VOX–ZrO2–SO42−, the sepiolite fibers coats the zirconia particles. This has a slightly negative influence on the overall SCR activity of fresh catalysts....

  13. New Trends in Gold Catalysts

    Directory of Open Access Journals (Sweden)

    Leonarda F. Liotta

    2014-07-01

    Full Text Available Gold is an element that has fascinated mankind for millennia. The catalytic properties of gold have been a source of debate, due to its complete chemical inertness when in a bulk form, while it can oxidize CO at temperatures as low as ~200 K when in a nanocrystalline state, as discovered by Haruta in the late 1980s [1]. Since then, extensive activity in both applied and fundamental research on gold has been initiated. The importance of the catalysis by gold represents one of the fasted growing fields in science and is proven by the promising applications in several fields, such as green chemistry and environmental catalysis, in the synthesis of single-walled carbon nanotubes, as modifiers of Ni catalysts for methane steam and dry reforming reactions and in biological and electrochemistry applications. The range of reactions catalyzed by gold, as well as the suitability of different supports and the influence of the preparation conditions have been widely explored and optimized in applied research [2]. Gold catalysts appeared to be very different from the other noble metal-based catalysts, due to their marked dependence on the preparation method, which is crucial for the genesis of the catalytic activity. Several methods, including deposition-precipitation, chemical vapor deposition and cation adsorption, have been applied for the preparation of gold catalysts over reducible oxides, like TiO2. Among these methods, deposition-precipitation has been the most frequently employed method for Au loading, and it involves the use of tetrachloroauric (III acid as a precursor. On the other hand, the number of articles dealing with Au-loaded acidic supports is smaller than that on basic supports, possibly because the deposition of [AuCl4]− or [AuOHxCl4−x]− species on acidic supports is difficult, due to their very low point of zero charge. Despite this challenge, several groups have reported the use of acidic zeolites as supports for gold. Zeolites

  14. Thermodynamic Properties of Supported Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Gorte, Raymond J.

    2014-03-26

    The goals of this work were to develop Coulometric Titration as a method for characterizing the thermodynamic redox properties of oxides and to apply this technique to the characterization of ceria- and vanadia-based catalysts. The redox properties of ceria and vanadia are a major part of what makes these materials catalytically active but their properties are also dependent on their structure and the presence of other oxides. Quantifying these properties through the measurement of oxidation energetics was the goal of this work.

  15. Rural Aging

    Science.gov (United States)

    ... Rural Health > Topics & States > Topics View more Rural Aging The nation's population is aging, and with that change comes increased healthcare needs. ... Disease Control and Prevention report, The State of Aging and Health in America 2013 , the population 65 ...

  16. Self-regeneration of a Pd-perovskite catalyst for automotive emissions control

    Science.gov (United States)

    Nishihata, Y.; Mizuki, J.; Akao, T.; Tanaka, H.; Uenishi, M.; Kimura, M.; Okamoto, T.; Hamada, N.

    2002-07-01

    Catalytic converters are widely used to reduce the amounts of nitrogen oxides, carbon monoxide and unburned hydrocarbons in automotive emissions. The catalysts are finely divided precious-metal particles dispersed on a solid support. During vehicle use, the converter is exposed to heat, which causes the metal particles to agglomerate and grow, and their overall surface area to decrease. As a result, catalyst activity deteriorates. The problem has been exacerbated in recent years by the trend to install catalytic converters closer to the engine, which ensures immediate activation of the catalyst on engine start-up, but also places demanding requirements on the catalyst's heat resistance. Conventional catalyst systems thus incorporate a sufficient excess of precious metal to guarantee continuous catalytic activity for vehicle use over 50,000miles (80,000km). Here we use X-ray diffraction and absorption to show that LaFe0.57Co0.38Pd0.05O3, one of the perovskite-based catalysts investigated for catalytic converter applications since the early 1970s, retains its high metal dispersion owing to structural responses to the fluctuations in exhaust-gas composition that occur in state-of-the-art petrol engines. We find that as the catalyst is cycled between oxidative and reductive atmospheres typically encountered in exhaust gas, palladium (Pd) reversibly moves into and out of the perovskite lattice. This movement appears to suppress the growth of metallic Pd particles, and hence explains the retention of high catalyst activity during long-term use and ageing.

  17. Evaluating processing temperature and feeding value of extruded-expelled soybean meal on nursery and finishing pig growth performance.

    Science.gov (United States)

    Webster, M J; Goodband, R D; Tokach, M D; Nelssen, J L; Dritz, S S; Woodworth, J C; De La Llata, M; Said, N W

    2003-08-01

    We conducted two experiments comparing the use of extruded-expelled soybean meal (EESoy) to solvent-extracted soybean meal (SBM) in swine diets. In Exp. 1, the objective was to determine the optimal processing temperature of EESoy for nursery pig growth performance. Pigs (n = 330, 13.2 +/- 2.3 kg of BW) were fed a control diet containing SBM with added fat or one of five diets containing EESoy extruded at 143.3, 148.9, 154.4, 160.0, or 165.6 degrees C. All diets were formulated on an equal apparent digestible lysine:ME ratio. From d 0 to 20, no differences were observed (P > 0.32) in ADG or ADFI (average of 544 and 924 g/d, respectively). However, gain:feed ratio (G/F) improved (quadratic, P improvement at 148.9 degrees C. In Exp. 2, the objective was to determine the feeding value of EESoy relative to SBM with or without added fat for growing-finishing pigs in a commercial production facility. A total of 1,200 gilts (initially 24.5 +/- 5.1 kg of BW) was used, with 25 pigs per pen and eight replications per treatment. Dietary treatments were arranged in a 2 x 3 factorial, with two sources of soybean meal (SBM or EESoy) and three levels of added fat. Pigs were phase-fed four diets over the experimental period and added fat (choice white grease) levels were 0, 3.4, and 7% initially, with the added fat levels decreasing in the next three dietary phases. Energy levels were based such that the higher energy in EESoy (with or without added fat) was calculated to be equal to that provided by SBM with added fat. From 24.5 to 61.2 kg, pigs fed EESoy had greater (P 0.10). For the overall growing-finishing period, ADG was unaffected (P > 0.61) by increasing energy density of the diet; however, ADFI decreased (P improves feed efficiency in finishing pigs reared in a commercial environment. PMID:12926785

  18. European workshop on spent catalysts. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    In 1999 and 2002 two well attended workshops on recycling, regeneration, reuse and disposal of spent catalysts took place in Frankfurt. This series has been continued in Berlin. The workshop was organized in collaboration with DGMK, the German Society for Petroleum and Coal Science and Technology. Contributions were in the following areas of catalyst deactivation: recycling of spent catalysts in chemical and petrochemical industry, recycling of precious metal catalysts and heterogenous base metal catalysts, legal aspects of transboundary movements, catalyst regeneration, quality control, slurry catalysts, commercial reactivation of hydrotreating catalysts. (uke)

  19. Immobilized Ruthenium Catalyst for Carbon Dioxide Hydrogenation

    Institute of Scientific and Technical Information of China (English)

    Ying Min YU; Jin Hua FEI; Yi Ping ZHANG; Xiao Ming ZHENG

    2006-01-01

    Three kinds of cross linked polystyrene resin (PS) supported ruthenium complexes were developed as catalysts for the synthesis of formic acid from carbon dioxide hydrogenation. Many factors, such as the functionalized supports, solvents and ligands, could influence their activities and reuse performances greatly. These immobilized catalysts also offer the industrial advantages such as easy separation.

  20. Advances in Catalyst Deactivation and Regeneration

    OpenAIRE

    Calvin H. Bartholomew; Morris D. Argyle

    2015-01-01

    Catalyst deactivation, the loss over time of catalytic activity and/or selectivity, is a problem of great and continuing concern in the practice of industrial catalytic processes. Costs to industry for catalyst replacement and process shutdown total tens of billions of dollars per year. [...

  1. Advances in Catalyst Deactivation and Regeneration

    Directory of Open Access Journals (Sweden)

    Calvin H. Bartholomew

    2015-06-01

    Full Text Available Catalyst deactivation, the loss over time of catalytic activity and/or selectivity, is a problem of great and continuing concern in the practice of industrial catalytic processes. Costs to industry for catalyst replacement and process shutdown total tens of billions of dollars per year. [...

  2. Hydrogenation catalyst based on modified carbon nanofibers

    International Nuclear Information System (INIS)

    The aim of this work was to study the palladium-carboxylated carbon nanofibers (CNF) as a catalyst for the hydrogenation of nitrobenzene model reaction. It is shown that the efficiency of the catalyst obtained more than 6 times higher than that of the industrial counterpart (Pd/C).

  3. Ligand iron catalysts for selective hydrogenation

    Science.gov (United States)

    Casey, Charles P.; Guan, Hairong

    2010-11-16

    Disclosed are iron ligand catalysts for selective hydrogenation of aldehydes, ketones and imines. A catalyst such as dicarbonyl iron hydride hydroxycyclopentadiene) complex uses the OH on the five member ring and hydrogen linked to the iron to facilitate hydrogenation reactions, particularly in the presence of hydrogen gas.

  4. Finite time extinction of superprocesses with catalysts

    OpenAIRE

    Dawson, Donald A.; Fleischmann, Klaus; Mueller, Carl

    2000-01-01

    Consider a catalytic super-Brownian motion $X =X^\\Gamma$ with finite variance branching. Here “catalytic ” means that branching of the reactant $X$ is only possible in the presence of some catalyst. Our intrinsic example of a catalyst is a stable random measure $\\Gamma$ on $\\mathsf{R}$ of index $0

  5. Preparation of Structured Catalysts for VOC Oxidation

    Czech Academy of Sciences Publication Activity Database

    Ludvíková, Jana; Jirátová, Květa; Kovanda, F.

    - : -, 2014, s. 155-156. ISBN N. [International Symposium on the Scientific Bases for the Preparation of Heterogeneous Catalysts /11./. Louvain-la-Neuve (BE), 06.07.2014-10.07.2014] Institutional support: RVO:67985858 Keywords : structured catalysts * transition metal oxides * VOC oxidation Subject RIV: CI - Industrial Chemistry, Chemical Engineering

  6. Novel non-platinum metal catalyst material

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to a novel non-platinum metal catalyst material for use in low temperature fuel cells and electrolysers and to fuel cells and electrolysers comprising the novel non-platinum metal catalyst material. The present invention also relates to a novel method for synthesizing...

  7. Nanometals and colloids as catalyst precursors

    Energy Technology Data Exchange (ETDEWEB)

    Boennemann, H.H. [Max-Planck-Institut fuer Kohlenforschung (Germany)

    1995-12-01

    Mono- or plurimetallic nanometals and colloids stabilized by surfactant molecules are discussed as pre-prepared precursors for heterogeneous catalysts. This {open_quotes}precursor concept{close_quotes} provides a novel access to supported metal catalysts having active components of controlled particle size, intermetallic ratio and particle structure on surfaces. Possible applications will also be presented.

  8. Leaching and comprehensive regulatory performance testing of an extruded bitumen containing a surrogate, sodium nitrate-based, low-level waste

    International Nuclear Information System (INIS)

    Performance test results obtained from laboratory testing of an extruded bitumen containing a surrogate, sodium nitrate-based waste are presented. A relatively viscous form of oxidized bitumen (ASTM D 312, Type III) has been tested and has been shown to meet all of the current regulatory performance criteria. Molded specimens were obtained using a 53-mm extruder. A surrogate, low-level, mixed, liquid waste was used. The surrogate waste contained ∼30 weight percent sodium nitrate, in addition to eight heavy metals, cold cesium, and strontium. Waste form specimens contained three levels of waste loading: 40, 50, and 60 weight percent salt. Results include thermal testing, extraction procedure toxicity tests, and 90-day American Nuclear Society 16.1 leach tests, as well as compressive strength tests

  9. Research on Extruded Products of Mgalzn Alloys – Microstructure and Mechanical Properties / Badania Wyrobów Wyciskanych Ze Stopów Mgalzn – Mikrostruktura I Właściwości Mechaniczne

    Directory of Open Access Journals (Sweden)

    Płonka B.

    2015-12-01

    Full Text Available The aim of the study was to test and assess products extruded from the magnesium alloys type MgAlZn: AZ31, AZ61 and AZ80A alloys in the form of Ø35mm round bars and 80x15mm flat bars. The test material was extruded in a direct system with the ram feed speed of 1 mm/s and the extrusion ratio λ = 7 ÷ 9. The extruded bars were examined in as-extruded state and after heat treatment to the T5 temper and T6 temper. The strength properties were tested and microstructure was examined with calculation of the average grain size.

  10. New catalysts for clean environment

    Energy Technology Data Exchange (ETDEWEB)

    Maijanen, A.; Hase, A. [eds.] [VTT Chemical Technology, Espoo (Finland)

    1996-12-31

    VTT launched a Research Programme on Chemical Reaction Mechanisms (CREAM) in 1993. The three-year programme (1993-1995) has focused on reaction mechanisms relevant to process industries and aimed at developing novel catalysts and biocatalysts for forest, food, and specialty chemicals industries as well as for energy production. The preliminary results of this programme have already been presented in the first symposium organized in Espoo in September 1994. To conclude the programme the second symposium is organized in Otaniemi, Espoo on January 29 - 30, 1996. Papers by 19 speakers and 17 poster presentations of the 1996 Symposium are included in this book. The Symposium consists of four sessions: Biotechnology for Natural Fibers Processing, New Biocatalysts, Catalysts for Clean Energy, and New Opportunities for Chemical Industry. The CREAM programme has tried to foresee solutions for the problems challenged by the public concern on environmental aspects, especially dealing with industrial processes and novel use of raw materials and energy. The programme has followed the basic routes that can lead to natural and simple solutions to develop processes in the fields of forest, food fine chemicals, and energy industry. This symposium presents the results of the programme to learn and further discuss together with the international experts that have been invited as keynote speakers. (author)

  11. Nanostructured Basic Catalysts: Opportunities for Renewable Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Conner, William C; Huber, George; Auerbach, Scott

    2009-06-30

    This research studied and developed novel basic catalysts for production of renewable chemicals and fuels from biomass. We focused on the development of unique porous structural-base catalysts zeolites. These catalysts were compared to conventional solid base materials for aldol condensation, that were being commercialized for production of fuels from biomass and would be pivotal in future biomass conversion to fuels and chemicals. Specifically, we had studied the aldolpyrolysis over zeolites and the trans-esterification of vegetable oil with methanol over mixed oxide catalysts. Our research has indicated that the base strength of framework nitrogen in nitrogen substituted zeolites (NH-zeolites) is nearly twice as strong as in standard zeolites. Nitrogen substituted catalysts have been synthesized from several zeolites (including FAU, MFI, BEA, and LTL) using NH3 treatment.

  12. Evaluation of the in vitro glycemic index of a fiber-rich extruded breakfast cereal produced with organic passion fruit fiber and corn flour

    Directory of Open Access Journals (Sweden)

    Maria Gabriela Vernaza Leoro

    2010-12-01

    Full Text Available The aim of this study was to determine the influence of process parameters and Passion Fruit Fiber (PFF addition on the Glycemic Index (GI of an extruded breakfast cereal. A 2³ Central Composite Rotational Design (CCRD was used, with the following independent variables: raw material moisture content (18-28%, 2nd and 3rd barrel zone temperatures (120-160 ºC, and PFF (0-30%. Raw materials (organic corn flour and organic PFF were characterized as to their proximate composition, particle size, and in vitro GI. The extrudates were characterized as to their in vitro GI. The Response Surface Methodology (RSM and Principal Component Analysis (PCA were used to analyze the results. Corn flour and PFF presented 8.55 and 7.63% protein, 2.61 and 0.60% fat, 0.52 and 6.17% ash, 78.77 and 78.86% carbohydrates (3 and 64% total dietary fiber, respectively. The corn flour particle size distribution was homogeneous, while PFF presented a heterogeneous particle size distribution. Corn flour and PFF presented values of GI of 48 and 45, respectively. When using RSM, no effect of the variables was observed in the GI of the extrudates (average value of 48.41, but PCA showed that the GI tended to be lower when processing at lower temperatures (158 ºC. When compared to white bread, the extrudates showed a reduction of the GI of up to 50%, and could be considered an interesting alternative in weight and glycemia control diets.

  13. Effect of heat treatment on microstructure and mechanical properties of hot-hydrostatically extruded 93W-4.9Ni-2.1Fe alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Yang, E-mail: hityyang@hit.edu.cn; Zhang, Wencong; Wang, Erde

    2015-02-15

    Highlights: • No work on heat treatment have been discussed for hot-hydrostatically extruded alloy. • Precipitations have been discussed in detail for the alloy by TEM. • Main strengthening mechanisms have been analyzed. - Abstract: Microstructure, mechanical properties and strengthening mechanisms of tungsten heavy alloys consolidated by liquid-phase sintered, hot-hydrostatic extrusion and heat treatment were investigated. The results showed that ultimate tensile strength σ{sub b} of 93W-4.9Ni-2.1Fe alloy with area reduction 75% extruded at 1200 °C could reach as high as about 1540 MPa and elongation could also reach 9.2%. Meanwhile, ultimate tensile strength and elongation by heat treatment remain 1487 MPa and 13.4%, respectively. Transmission electron microscopy observation revealed that as-extruded alloys were characterized by fine subgrains in elongated tungsten grains and dynamically re-crystallized grains in Ni-Fe-W matrix phase. Tungsten subgrains subsequently grew up a bit and nanocrystalline W with most of them being less than 100 nm in length showing a needle precipitated in Ni-Fe-W matrix phase after heat treatment at 1000 °C for 1 h. Results indicate that one of the strengthening mechanisms is interface strengthening between tungsten and matrix phase due to severe plastic deformation, which can be explained via aspect ratio correlated with deformed tungsten particles. The other strengthening mechanism can be attributed to precipitated nanocrystalline W during heat treatment in Ni-Fe-W matrix phase of the as-extruded alloy with area reduction 75%.

  14. Effect of heat treatment on microstructure and mechanical properties of hot-hydrostatically extruded 93W-4.9Ni-2.1Fe alloy

    International Nuclear Information System (INIS)

    Highlights: • No work on heat treatment have been discussed for hot-hydrostatically extruded alloy. • Precipitations have been discussed in detail for the alloy by TEM. • Main strengthening mechanisms have been analyzed. - Abstract: Microstructure, mechanical properties and strengthening mechanisms of tungsten heavy alloys consolidated by liquid-phase sintered, hot-hydrostatic extrusion and heat treatment were investigated. The results showed that ultimate tensile strength σb of 93W-4.9Ni-2.1Fe alloy with area reduction 75% extruded at 1200 °C could reach as high as about 1540 MPa and elongation could also reach 9.2%. Meanwhile, ultimate tensile strength and elongation by heat treatment remain 1487 MPa and 13.4%, respectively. Transmission electron microscopy observation revealed that as-extruded alloys were characterized by fine subgrains in elongated tungsten grains and dynamically re-crystallized grains in Ni-Fe-W matrix phase. Tungsten subgrains subsequently grew up a bit and nanocrystalline W with most of them being less than 100 nm in length showing a needle precipitated in Ni-Fe-W matrix phase after heat treatment at 1000 °C for 1 h. Results indicate that one of the strengthening mechanisms is interface strengthening between tungsten and matrix phase due to severe plastic deformation, which can be explained via aspect ratio correlated with deformed tungsten particles. The other strengthening mechanism can be attributed to precipitated nanocrystalline W during heat treatment in Ni-Fe-W matrix phase of the as-extruded alloy with area reduction 75%

  15. INFLUENCE OF WHEAT BRAN ADDITION AND OF THERMOPLASTIC EXTRUSION PROCESS PARAMETERS ON PHYSICAL PROPERTIES OF CORN-BASED EXPANDED EXTRUDED SNACKS

    Directory of Open Access Journals (Sweden)

    Reinaldo Eduardo FERREIRA

    2011-12-01

    Full Text Available Corn-based expanded extruded snacks containing wheat bran as dietary fiber source were evaluated with respect to instrumental hardness, expansion index and color (L* - lightness. Internal cell structure was observed through Scanning Electron Microscopy (SEM. Snacks were produced following a 23 complete factorial design, in a single screw extruder (model GNF 1014/2, BRABENDER, Germany. The three independent variables studied were: moisture (from 16.3 to 29.7%; temperature of the 2nd and 3rd extruder zones (from 104.8 to 155.2ºC; and wheat bran content (from 0 to 24.6%. An increase in temperature resulted in lower extrudate hardness values, which varied from 1.6 to 4.8kgf. Higher moisture and lower wheat bran contents resulted in snacks with greater hardness. Expansion index, that varied from 1.7 to 3.7, was mainly influenced by moisture and temperature, being that higher moisture values combined to higher temperatures resulted in lower expansion indexes. The snacks presented lightness (L* values between 42.77 and 64.41, being the temperature the variable that most influenced the values, because higher values of temperature resulted in higher L* values. Observing the snacks through Scanning Electron Microscopy, the influence of wheat bran could be observed, as higher contents of wheat bran contributed to the formation of cells with reduced sizes. During the sensory analysis, snacks with and without wheat bran, optimum and control, respectively, produced under the same temperature (130°C and moisture (23% were compared. Snacks were evaluated by 40 judges through an acceptance test, using a 9-point hedonic scale (mixed structured, in relation to color, appearance, texture (hardness, taste and global evaluation. Optimum and control snacks differed significantly at 95% significance, with the best acceptance for all attributes being obtained for the control.

  16. Direct-reading design charts for 75S-T6 aluminum-alloy flat compression panels having longitudinal extruded Z-section stiffeners

    Science.gov (United States)

    Hickman, William A; Dow, Norris F

    1951-01-01

    Direct-reading design charts are presented for 75S-T6 aluminum-alloy flat compression panels having longitudinal extruded Z-section stiffeners. These charts, which cover a wide range of proportions, make possible the direct determination of the stress and all panel dimensions required to carry a given intensity of loading with a given skin thickness and effective length of panel.

  17. Response of a highly segmented extruded lead glass calorimeter to electrons and pions between 15 and 45 GeV/c

    International Nuclear Information System (INIS)

    We have studied the energy resolution, hadron rejection and ability to distinguish overlapped events for a highly segmented electromagnetic calorimeter using unpolished extruded lead glass bars. Energy resolution is in agreement with previous measurements of more conventional calorimeters. Hadron rejections of 10-3 are achieved, without the use of particle momentum information. Overlapped events of π+--γ are shown to be rejected at the level of 10-2. A powerful method for predicting shower leakage energy is also presented

  18. Microstructural Studies of Texturized Vegetable Protein Products: Effects of Oil Addition and Transformation of Raw Materials in Various Sections of a Twin Screw Extruder

    OpenAIRE

    Gwiazda, S.; Noguchi, A; Saio, K.

    1987-01-01

    In high-temperature short- time extrusion cooking with a twin screw extruder , effects of oil addition to defatted soybean flour and microstructural transformation of full - fat soybean flour during cooking , were investigated by use of a light microscope. At levels up to 15% , soybean oil was distributed in the protein and carbohydrate matrix as small, spherical drops under the experimental conditions used in this study. However , oil contents above 15% significantly prevented formation of w...

  19. Aqueous extraction of oleic sunflower oil from whole plant by twin-screw extruder: feasibility study, influence of screw configuration and operating conditions

    OpenAIRE

    Evon, Philippe; Vandenbossche, Virginie; Pontalier, Pierre-Yves; Rigal, Luc

    2007-01-01

    Aqueous extraction process using water alone as medium is an alternative to the solvent oil extraction process from oilseeds. It enables simultaneous recovery of oil and protein. The implementation of a co-rotating twin-screw extruder allows the aqueous extraction of oleic sunflower oil from whole plant. Screw configuration, screw rotation speed and whole plant input flow rate affect directly the efficiency of liquid/solid separation. Wringing out the mixing is possible because of the natu...

  20. Manufacturing of renewable and biodegradable fiberboards from cake generated during biorefinery of sunflower whole plant in twin-screw extruder: Influence of thermo-pressing conditions

    OpenAIRE

    Evon, Philippe; Vandenbossche, Virginie; Rigal, Luc

    2012-01-01

    The starting material used in this study was a cake generated during thermo-mechanical fractionation of sunflower (Helianthus annuus L.) whole plant in a twin-screw extruder. It was slightly deoiled (16.7% of oil in dry matter). Composed mainly of fibers and proteins, it could be considered as a natural composite and was processed successfully into fiberboards by thermo-pressing. This study aimed to evaluate the influence of thermo-pressing conditions on mechanical and heat insulation propert...