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Sample records for aged catalyst extrudates

  1. Active carbon catalyst for heavy oil upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Fukuyama, Hidetsugu; Terai, Satoshi [Technology Research Center, Toyo Engineering Corporation, 1818 Azafujimi, Togo, Mobara-shi, Chiba 297-00017 (Japan); Uchida, Masayuki [Business Planning and Exploring Department, Overseas Business Development and Marketing Division, Toyo Engineering Corporation, 2-8-1 Akanehama, Narashino-shi, Chiba 275-0024 (Japan); Cano, Jose L.; Ancheyta, Jorge [Maya Crude Treatment Project, Instituto Mexicano del Petroleo, Eje Central Lazaro Cardenas No. 152, Col. San Bartolo Atepehuacan, Mexico D.F. 07730 (Mexico)

    2004-11-24

    The active carbon (AC) catalyst was studied by hydrocracking of Middle Eastern vacuum residue (VR) for heavy oil upgrading. It was observed that the active carbon has the affinity to heavy hydrocarbon compounds and adsorption selectivity to asphaltenes, and exhibits better ability to restrict the coke formation during the hydrocracking reaction of VR. The mesopore of active carbon was thought to play an important role for effective conversion of heavy hydrocarbon compounds into lighter fractions restricting carbon formation. The performance of the AC catalyst was examined by continuous hydrocracking by CSTR for the removal of such impurities as sulfur and heavy metals (nickel and vanadium), which are mostly concentrated in the asphaltenes. The AC catalyst was confirmed to be very effective for the removal of heavy metals from Middle Eastern VR, Maya/Istmo VR and Maya VR. The extruded AC catalysts were produced by industrial manufacturing method. The application test of the extruded AC catalyst for ebullating-bed reactor as one of the commercially applicable reactors was carried out at the ebullating-bed pilot plant for 500h. The ebullition of the extruded AC catalyst was successfully traced and confirmed by existing {gamma}-ray density meter. The extruded AC catalyst showed stable performance with less sediment formation at an equivalent conversion by conventional alumina catalyst at commercial ebullating-bed unit. The degradation of the AC catalyst at the aging test was observed to be less than that of the conventional alumina catalyst. Thus, the AC catalyst was confirmed to be effective and suitable for upgrading of heavy oil, especially such heavy oils as Maya, which contains much heavy metals.

  2. Effect of cold rolling on microstructure and mechanical property of extruded Mg–4Sm alloy during aging

    Energy Technology Data Exchange (ETDEWEB)

    Li, Rongguang, E-mail: lirongguang1980@126.com [School of Mechanical Engineering, Shenyang University of Chemical Technology, Shenyang 110142 (China); Xin, Renlong; Chapuis, Adrien; Liu, Qing [School of Materials Science and Engineering, Chongqing University, Chongqing 400045 (China); Fu, Guangyan; Zong, Lin; Yu, Yongmei; Guo, Beitao; Guo, Shuguo [School of Mechanical Engineering, Shenyang University of Chemical Technology, Shenyang 110142 (China)

    2016-02-15

    Microstructure and mechanical properties of the Mg–4Sm (wt.%) alloy, prepared via combined processes of extrusion, cold rolling and aging, have been investigated. The hot extruded alloy exhibits a weak rare earth magnesium alloy texture with < 11 − 21 >//ED, while the cold-rolled alloy shows a stronger basal texture with < 0001 >//ND. Many tensile twins and double twins are observed in grains after rolling. The cold-rolled alloy shows a weak age-hardening response compared with the extruded alloy, which is the result of more precipitation in the twin boundary during aging. The rolled alloy exhibits almost no precipitate free zone during aging compared with the extruded alloy. The higher proof stress of the rolled alloy in peak-aged condition is attributed to the presence of twin boundaries, stronger basal texture, higher dislocation density, and the suppression of precipitate free zone compared with the extruded alloy. - Highlights: • No precipitate free zone appears in cold-rolled alloy after aging. • Segregation and precipitates are observed in twin boundaries and grain boundaries. • Cold-rolled alloy shows a weak age-hardening response.

  3. Studies on recycling and utilization of spent catalysts. Preparation of active hydrodemetallization catalyst compositions from spent residue hydroprocessing catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Marafi, Meena; Stanislaus, Antony [Petroleum Refining Department, Petroleum Research and Studies Center, Kuwait Institute for Scientific Research, P.O. Box 24885, Safat (Kuwait)

    2007-02-15

    Spent catalysts form a major source of solid wastes in the petroleum refining industries. Due to environmental concerns, increasing emphasis has been placed on the development of recycling processes for the waste catalyst materials as much as possible. In the present study the potential reuse of spent catalysts in the preparation of active new catalysts for residual oil hydrotreating was examined. A series of catalysts were prepared by mixing and extruding spent residue hydroprocessing catalysts that contained C, V, Mo, Ni and Al{sub 2}O{sub 3} with boehmite in different proportions. All prepared catalysts were characterized by chemical analysis and by surface area, pore volume, pore size and crushing strength measurements. The hydrodesulfurization (HDS) and hydrodemetallization (HDM) activities of the catalysts were evaluated by testing in a high pressure fixed-bed microreactor unit using Kuwait atmospheric residue as feed. A commercial HDM catalyst was also tested under similar operating conditions and their HDS and HDM activities were compared with that of the prepared catalysts. The results revealed that catalyst prepared with addition of up to 40 wt% spent catalyst to boehmite had fairly high surface area and pore volume together with large pores. The catalyst prepared by mixing and extruding about 40 wt% spent catalyst with boehmite was relatively more active for promoting HDM and HDS reactions than a reference commercial HDM catalyst. The formation of some kind of new active sites from the metals (V, Mo and Ni) present in the spent catalyst is suggested to be responsible for the high HDM activity of the prepared catalyst. (author)

  4. NO formation during burnoff of spent hydroprocessing catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Zaitlin, L.; Laugher, R. (CANMET, Ottawa, ON (Canada). Energy Research Laboratories)

    1993-11-01

    Temperature-programmed oxidation (from room temperature to 600[degree]C) was performed on operating forms of aged CoMo (extrudate) and NiMo (chestnut bur-like) as well as powder forms, with continuous on-line analysis for NO, CO, CO[sub 2] and SO[sub 2]. For all catalysts, NO formation was delayed by that of CO and CO[sub 2], indicating either a strong interaction of nitrogen-containing compounds with the catalyst surface or a lower reactivity of nitrogen during burnoff compared with that of carbon. The existence of diffusion effects during burnoff was quite evident. These effects were influenced by the catalyst structure and the level of catalyst deactivation. 18 refs., 6 figs., 1 tab.

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

    International Nuclear Information System (INIS)

    Peizheng Zhou

    2002-01-01

    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/CO 2 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

  6. 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.

  7. Performance Testing of Hydrodesulfurization Catalysts Using a Single-Pellet-String Reactor

    NARCIS (Netherlands)

    Moonen, Roel; Ras, Erik Jan; Harvey, Clare; Alles, Jeroen; Moulijn, J.A.

    2017-01-01

    Small-scale parallel trickle-bed reactors were used to evaluate the performance of a commercial hydrodesulfurization catalyst under industrially relevant conditions. Catalyst extrudates were loaded as a single string in reactor tubes. It is demonstrated that product sulfur levels and densities

  8. Effect of Y addition on the aging hardening behavior and precipitation evolution of extruded Mg-Al-Zn alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ren, L.B. [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Chengdu, Sichuan 610031 (China); School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Quan, G.F., E-mail: quangf@home.swjtu.edu.cn [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Chengdu, Sichuan 610031 (China); School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Zhou, M.Y.; Guo, Y.Y.; Jiang, Z.Z.; Tang, Q. [Key Laboratory of Advanced Technologies of Materials, Ministry of Education, Chengdu, Sichuan 610031 (China); School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China)

    2017-04-06

    Abstract:: The 443 K aging hardening behavior and microstructure evolution of extruded Mg-Al-Zn-Y alloys was investigated in aspects of yttrium (Y) content (0.2–0.8 wt%), holding time (0.5–156 h) and the initial states (as-extruded, solution treated). The grain size, precipitation evolution, phases and chemical composition were characterized by the optical microscope, scanning electron microscope, X-ray diffraction, and energy dispersive spectrometer, respectively. The corresponding mechanical response, including the hardness, uniaxial tensile strength were measured with the Vickers hardness tester and universal testing machine, respectively. The results show that, firstly, there is reversal hardness anisotropy between extrusion direction and normal direction in as-extruded Mg-Al-Zn-Y sheets compared with T5 treated ones. Secondly, the short-term aging softening exist at the beginning of T5 treatment which results in a lower hardness even be close to that of solution treated ones, but not for T6 conditions. Thirdly, the suppression of discontinuous precipitation during the aging treatment become more remarkable with increasing Y addition which because of the reduction of diffusional coherency strain near grain boundary, increasing activation energy for the discontinuous precipitates (β-Mg{sub 17}Al{sub 12} phase, DPs) formation and the dilution region of Al near the Al{sub 2}Y. Serrated GBs can also provide more nucleation sites for DPs and lead to relatively more precipitates during T5 treatment. Moreover, the proportional precipitation strengthening in yield strength and hardness was verified in Mg-Al-Zn-Y alloy during the aging process.

  9. Basic study of catalyst aging in the H-coal process

    Energy Technology Data Exchange (ETDEWEB)

    Cable, T.L.; Massoth, F.E.; Thomas, M.G.

    1985-04-01

    Samples of CoMo/Al/sub 2/O/sub 3/ catalysts used in an H-coal process demonstration run were studied to determine causes of catalyst deactivation. Physical and surface properties of the aged and regenerated catalysts were examined. Model compounds were used to assess four catalyst activity functions, viz., hydrodesulfurization (HDS), hydrogenation, cracking and hydrodeoxygenation (HDO). Other tests were performed to study the effects of coke and metals separately on the four catalyst activity functions. Catalyst coke content and metal deposits first increased rapidly, then more gradually with exposure time in the process run. Surface area and pore volume markedly decreased with exposure time. Catalyst activities of aged catalysts showed a rapid decline with exposure time. One-day exposure to coal resulted in significant losses in HDS and hydrogenation activities and nearly complete loss in cracking and HDO activities. Although metal deposits caused some permanent catalyst deactivation, coke had a much greater effect. Regenerated catalysts showed less recovery of catalytic activity as processing time increased. These results agreed well with product inspections from the process run. Oxygen chemisorption on aged-regenerated catalysts decreased with catalyst exposure time, indicating a significant loss of active sites. However, ESCA results showed no evidence of extensive sintering of the active MoS/sub 2/ phase. Permanent deactivation of the longer-time exposed catalysts can be ascribed, at least partly, to lateral growth of the active molybdenum sulfide phase. In addition, some loss in cobalt promotion occurred early in the process, which may account for the rapid loss in HDS and HDO activity in regenerated catalysts. 24 references.

  10. Biaxial vent extruder

    International Nuclear Information System (INIS)

    Idemoto, A.; Maki, Y.; Oda, N.

    1981-01-01

    A biaxial vent extruder is described for processing of slurry-like waste fluids or radioactive waste fluids which have a hopper cylinger, a solidifying substance port and a solidified substance port. A plurality of vent cylinders each having a vent port are provided with a plunger type scraper. An extruding cylinder having a single opening for a main screw is connected to the assembled vent cylinders. The main screw extends to the upstream end of the extruding cylinder and a sub-screw extends to the extruding cylinder. The screws each having a full flight engaging the other and a set of rings are mounted on the screws near the respective vent port inlets. The screws are rotated in different directions and inwardly with respect to the vent ports. Rotors may be mounted on the screws to break down solid particles

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

    International Nuclear Information System (INIS)

    Suzuki, Hiroshi; Miura, Akihiko

    1999-09-01

    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)

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

    DEFF Research Database (Denmark)

    Rasmussen, Søren Birk; Due-Hansen, Johannes; Yates, M.

    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/....../w sepiolite is the optimal catalyst composition....

  13. Reuse of Hydrotreating Spent Catalyst

    International Nuclear Information System (INIS)

    Habib, A.M.; Menoufy, M.F.; Amhed, S.H.

    2004-01-01

    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

  14. 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.

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

    International Nuclear Information System (INIS)

    Voigt, Thomas; Malonn, Tim; Shah, Surendra P.

    2006-01-01

    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

  16. Intelligent Extruder

    Energy Technology Data Exchange (ETDEWEB)

    AlperEker; Mark Giammattia; Paul Houpt; Aditya Kumar; Oscar Montero; Minesh Shah; Norberto Silvi; Timothy Cribbs

    2003-04-24

    ''Intelligent Extruder'' described in this report is a software system and associated support services for monitoring and control of compounding extruders to improve material quality, reduce waste and energy use, with minimal addition of new sensors or changes to the factory floor system components. Emphasis is on process improvements to the mixing, melting and de-volatilization of base resins, fillers, pigments, fire retardants and other additives in the :finishing'' stage of high value added engineering polymer materials. While GE Plastics materials were used for experimental studies throughout the program, the concepts and principles are broadly applicable to other manufacturers materials. The project involved a joint collaboration among GE Global Research, GE Industrial Systems and Coperion Werner & Pleiderer, USA, a major manufacturer of compounding equipment. Scope of the program included development of a algorithms for monitoring process material viscosity without rheological sensors or generating waste streams, a novel detection scheme for rapid detection of process upsets and an adaptive feedback control system to compensate for process upsets where at line adjustments are feasible. Software algorithms were implemented and tested on a laboratory scale extruder (50 lb/hr) at GE Global Research and data from a production scale system (2000 lb/hr) at GE Plastics was used to validate the monitoring and detection software. Although not evaluated experimentally, a new concept for extruder process monitoring through estimation of high frequency drive torque without strain gauges is developed and demonstrated in simulation. A plan to commercialize the software system is outlined, but commercialization has not been completed.

  17. 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.

  18. Fluidized bed catalytic pyrolysis of eucalyptus over hzsm-5: effect of acid density and gallium modification on catalyst deactivation

    Science.gov (United States)

    Catalytic fast pyrolysis of eucalyptus wood was performed on a continuous laboratory scale fluidized bed fast pyrolysis system. Catalytic activity was monitored from use of fresh catalyst up to a cumulative biomass to catalyst ratio (B/C) of 4/1 over extruded pellets of three different ZSM-5 catalys...

  19. Physicochemical Properties of Flaxseed Fortified Extruded Bean Snack

    Directory of Open Access Journals (Sweden)

    Naveen Vadukapuram

    2014-01-01

    Full Text Available Milled flaxseed was incorporated (0–20% into a combination of bean-corn flours and extruded in a twin screw extruder using corn curl method. Physicochemical parameters such as water activity, color, expansion ratio, bulk density, lipid content, and peroxide values of extruded snack were analyzed. Scanning electron micrographs were taken. Peroxide values and propanal contents were measured over four months of storage. Rancidity scores of extruded snack were measured using a trained panel. As expected, omega-3 fatty acids and bulk density increased with increasing flaxseed fortification levels. Extrudates with more flaxseed had decreased lightness values and expansion ratios. However, only the 15 and 20% flaxseed containing extrudates had expansion ratios that were significantly (P≤0.05 different from the control. In general, no significant difference (P>0.05 in water activity values was observed in the flaxseed fortified extrudates, except in the navy-corn based extrudates. Peroxide values increased with increased flaxseed levels and over a storage period. However, propanal values did not change significantly in the 5–10% flaxseed fortified extrudates but increased in extrudates with higher levels of flaxseed. Rancidity scores were correlated with peroxide values and did not increase significantly during storage under nitrogen flushed conditions.

  20. Physicochemical Properties of Flaxseed Fortified Extruded Bean Snack.

    Science.gov (United States)

    Vadukapuram, Naveen; Hall, Clifford; Tulbek, Mehmet; Niehaus, Mary

    2014-01-01

    Milled flaxseed was incorporated (0-20%) into a combination of bean-corn flours and extruded in a twin screw extruder using corn curl method. Physicochemical parameters such as water activity, color, expansion ratio, bulk density, lipid content, and peroxide values of extruded snack were analyzed. Scanning electron micrographs were taken. Peroxide values and propanal contents were measured over four months of storage. Rancidity scores of extruded snack were measured using a trained panel. As expected, omega-3 fatty acids and bulk density increased with increasing flaxseed fortification levels. Extrudates with more flaxseed had decreased lightness values and expansion ratios. However, only the 15 and 20% flaxseed containing extrudates had expansion ratios that were significantly (P ≤ 0.05) different from the control. In general, no significant difference (P > 0.05) in water activity values was observed in the flaxseed fortified extrudates, except in the navy-corn based extrudates. Peroxide values increased with increased flaxseed levels and over a storage period. However, propanal values did not change significantly in the 5-10% flaxseed fortified extrudates but increased in extrudates with higher levels of flaxseed. Rancidity scores were correlated with peroxide values and did not increase significantly during storage under nitrogen flushed conditions.

  1. EFFECT OF ADDITION OF PROTEIN PREPARATIONS ON THE QUALITY OF EXTRUDED MAIZE EXTRUDATES

    Directory of Open Access Journals (Sweden)

    Elżbieta Rytel

    2013-02-01

    Full Text Available The method of extrusion enables enrichment of snacking products with protein preparation simultaneously providing a high quality of end products. Maize semolina with particle size of 500-1250 μm was used as raw material and as additives soybean protein isolate, distillery yeast Safethanol 3035 and laboratory obtained potato protein preparation. Snacks were determined for contents of dry matter, protein, fat as well as for texture, volume weight, bulk density and sensory traits. The application of 3% and 6% additions of protein preparations in extruded snacks production was found to exert a beneficial effect on their chemical composition without deteriorating sensory characteristics. The higher, 6%, addition of proteins to extrudates turned out to significantly reduce content of fat (by 18% and ash (by 50%, and to increase total protein content by 26%, on average, in the products examined as compared to the samples free of additives. The addition of potato protein to extrudates, especially at the higher dose (6%, significantly improved their consistency and texture, simultaneously diminishing the expansion ratio of ready products. The higher (6% addition of yeast protein applied in the production of extrudates resulted in slight deterioration of their taste and aroma, yet had a positive effect on the structure and expansion ratio of the ready products. The extrudates produced with the addition of soybean protein were characterized by a good expansion ratio, uniform structure, irrespective of preparation dose and simultaneously demonstrated lower bulk mass as compared to the other products obtained in the experiment.

  2. Preparation of an extruded fish snack using twin screw extruder and the storage characteristics of the product

    OpenAIRE

    Sharma, S.K.; Basu, S.

    2003-01-01

    A value-added extruded fish product was prepared with corn flour (80%) and fish (sciaenid) powder (20%), using a twin-screw extruder. The effect of different parameters like moisture, temperature, fish powder concentration, speed of the extruder and die-diameter on expansion ratio and crisp texture were studied. The storage characteristics of the final product were studied using three different types of packaging under nitrogen flushing. The study revealed that aluminum foil is the best packa...

  3. Physicochemical Properties of Flaxseed Fortified Extruded Bean Snack

    OpenAIRE

    Vadukapuram, Naveen; Hall, CliffordIII; Tulbek, Mehmet; Niehaus, Mary

    2014-01-01

    Milled flaxseed was incorporated (0?20%) into a combination of bean-corn flours and extruded in a twin screw extruder using corn curl method. Physicochemical parameters such as water activity, color, expansion ratio, bulk density, lipid content, and peroxide values of extruded snack were analyzed. Scanning electron micrographs were taken. Peroxide values and propanal contents were measured over four months of storage. Rancidity scores of extruded snack were measured using a trained panel. As ...

  4. TEXTURE ANALYSIS OF EXTRUDED APPLE POMACE - WHEAT SEMOLINA BLENDS

    Directory of Open Access Journals (Sweden)

    Ivan Bakalov

    2016-03-01

    Full Text Available Apple pomace - wheat semolina blends were extruded in a laboratory single screw extruder (Brabender 20 DN, Germany. Effects apple pomace content, moisture content, screw speed, and temperature of final cooking zone on texture of extrudates were studied applying response surface methodology. The texture characteristics of the extrudates were measured using a TA.XT Plus Texture Analyser, Stable Micro Systems.

  5. Extruding plastic scintillator at Fermilab

    International Nuclear Information System (INIS)

    Pla-Dalmau, Anna; Bross, Alain D.; Rykalin, Viktor V.

    2003-01-01

    An understanding of the costs involved in the production of plastic scintillators and the development of a less expensive material have become necessary with the prospects of building very large plastic scintillation detectors. Several factors contribute to the high cost of plastic scintillating sheets, but the principal reason is the labor-intensive nature of the manufacturing process. In order to significantly lower the costs, the current casting procedures had to be abandoned. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. This concept was tested and high quality extruded plastic scintillator was produced. The D0 and MINOS experiments are already using extruded scintillator strips in their detectors. An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. This paper will discuss the characteristics of extruded plastic scintillator and its raw materials, the different manufacturing techniques and the current R andD program at Fermilab

  6. Extruded plastic scintillator for MINERvA

    International Nuclear Information System (INIS)

    Pla-Dalmau, Anna; Bross, Alan D.; FermilabRykalin, Victor V.; Wood, Brian M.; NICADD, DeKalb

    2005-01-01

    An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. The D0 and MINOS experiments are already using extruded scintillator strips in their detectors. A new experiment at Fermilab is pursuing the use of extruded plastic scintillator. A new plastic scintillator strip is being tested and its properties characterized. The initial results are presented here

  7. Effect of heat treatment on elevated temperature tensile and creep properties of the extruded Mg–6Gd–4Y–Nd–0.7Zr alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Lin, E-mail: yuanlin@hit.edu.cn; Shi, Wenchao; Jiang, WenMao; Zhao, Zhe; Shan, Debin

    2016-03-21

    The light and heavy rare earth elements are added to the magnesium alloys to improve the strengths and the creep resistance. The age hardening behaviors of the extruded Mg–6Gd–4Y–Nd–0.7Zr alloy aged at 200, 225 and 250 °C were investigated. Tensile tests and creep tests of the extruded and extruded-T5 Mg–6Gd–4Y–Nd–0.7Zr were carried out at 150–300 °C. The relationship between the microstructure and the properties of the extruded-T5 Mg–6Gd–4Y–Nd–0.7Zr alloy was studied. The result shows that the extruded Mg–6Gd–4Y–Nd–0.7Zr (contained less than 10 wt% Gd) peak aged at 225 °C for 72 h has the excellent creep resistance and high strengths with the UTS more than 350 MPa from room temperature to 200 °C, which are correlative with the precipitates. The high dense and uniform distribution of β′ phase with good heat stability precipitates inhibiting the dislocation motion contributes to age hardening, accelerates the ageing hardening response and increases the creep resistance. The artificially aged (T5) at low temperature further creep tested and tensile tested at higher temperatures decreases the resistance to the dislocation motion and the grain boundary sliding, resulting in the reduction in creep properties and strengths of the extruded-T5 Mg–6Gd–4Y–Nd–0.7Zr alloy above 225 °C.

  8. 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 thickness range is thickness < +/- 0.1mm.

  9. The extrudate swell of HDPE: Rheological effects

    Science.gov (United States)

    Konaganti, Vinod Kumar; Ansari, Mahmoud; Mitsoulis, Evan; Hatzikiriakos, Savvas G.

    2017-05-01

    The extrudate swell of an industrial grade high molecular weight high-density polyethylene (HDPE) in capillary dies is studied experimentally and numerically using the integral K-BKZ constitutive model. The non-linear viscoelastic flow properties of the polymer resin are studied for a broad range of large step shear strains and high shear rates using the cone partitioned plate (CPP) geometry of the stress/strain controlled rotational rheometer. This allowed the determination of the rheological parameters accurately, in particular the damping function, which is proven to be the most important in simulating transient flows such as extrudate swell. A series of simulations performed using the integral K-BKZ Wagner model with different values of the Wagner exponent n, ranging from n=0.15 to 0.5, demonstrates that the extrudate swell predictions are extremely sensitive to the Wagner damping function exponent. Using the correct n-value resulted in extrudate swell predictions that are in excellent agreement with experimental measurements.

  10. Apically-extruded debris using the ProTaper system.

    Science.gov (United States)

    Azar, Nasim Gheshlaghi; Ebrahimi, Gholamreza

    2005-04-01

    The purpose of this in vitro study was to determine the quantity of debris and irrigant extruded apically using the ProTaper system compared to ProFiles and K-Flexofiles. Thirty-six mesio-buccal root canals of human mandibular molars were selected and divided into three groups of twelve canals. Two groups were instrumented with ProFiles and ProTapers according to the manufacturer's instructions. The other group was instrumented with K-Flexofiles using the step-back technique. A standard amount of irrigant was used for each canal. Apically-extruded debris and irrigant was collected in pre-weighed vials. The mean weight of extruded debris and irrigant for each group was statistically analysed using Student's t-test and one-way ANOVA. All instrumentation techniques produced extruded debris and irrigant. Although the mean amount of extrusion with the step-back technique was higher than the two rotary systems, there was no significant difference between the three groups (p > 0.05). NiTi rotary systems were associated with less apical extrusion, but were not significantly better than hand file instrumentation. All techniques extruded debris.

  11. Properties of extrudates from sorghum varieties | Byaruhanga ...

    African Journals Online (AJOL)

    Physical-chemical properties of the extrudates including, lateral expansion, bulk density, hardness, water absorption index, water solubility index, as well as proximate composition were determined. The extrudates exhibited 240-300% lateral expansion and 0.067-0.095 g cm-3 bulk density. The water absorption index was ...

  12. Influence of extruder screws speed and process temperature on the extrudate shape changes of the maize-spelt blends

    Directory of Open Access Journals (Sweden)

    Tomasz Żelaziński

    2018-01-01

    Full Text Available The objective of the study was examination of changes in the shape factors of extruded products, which occur as a result of different settings of the extrusion process variables. Samples analysed included products created by means of the extrusion process from a mixture of spelt flour and cornmeal, with the share of spelt at 70 to 100%. The samples were made with the use of a co-rotating twin screw extruder. Two speeds of extruder screw rotation (300 and 350 rpm as well as two levels of temperature (120 and 140°C were set during the investigation. The samples obtained were photographed in a light box, following which they underwent an image analysis with the use of specialist vision software. Four shape-related factors were determined: area, elongation factor, Heywood circularity factor and compactness factor. It was determined that the product shape changed significantly depending on the share of spelt flour in the mixture. Moreover, it was observed that change in the screw rotation speed within the analysed range may cause material changes in the shape of particular extrudates.

  13. Properties of extruded snacks supplemented with amaranth grain grits

    Directory of Open Access Journals (Sweden)

    Hadnađev Miroslav S.

    2009-01-01

    Full Text Available Extruded amaranth grain products have specific aroma and can be used as snack food, supplement in breakfast cereals, or as raw material for further processing. Extruded products of corn-amaranth grits blends, containing 20% or 50% amaranth grain grits, were produced by extrusion-cooking using a laboratory Brabender single screw extruder 20 DN. Extrudates with various texture were obtained. During extrusion process starch granules are partially degraded, hence rheological properties were examined. All samples exhibited thixotropic flow behavior. Those samples in which part of the corn grits was replaced with amaranth one had lower viscosity and exhibited lower level of structuration during storage.

  14. Optimization and Numerical Simulation of Outlet of Twin Screw Extruder

    Directory of Open Access Journals (Sweden)

    Zhang Yuan

    2018-01-01

    Full Text Available In view of the unreasonable design of non-intermeshing counter-rotating twin screw extruder die, the problem of productivity reduction was discussed. Firstly, the mathematical model of extruder productivity was established. The extruder die model was improved. Secondly, the force analysis of twin screw extruder physical model was carried out. Meanwhile, A combination of mechanical analysis and numerical simulation was adopted. The velocity field, pressure field and viscosity field were calculated by Mini-Element interpolation method, linear interpolation method and Picard iterative convergence method respectively. The influence of die model on the quantity of each field before and after improvement was analyzed. The results show that the improved model had increased the rheological parameters of the flow field, the leakage and reverse flow decreased. Through post-processing calculation, the productivity of the third dies extruder was 10% higher than before. The research results provide a theoretical basis for the design and optimization of die model of non intermeshing counter-rotating twin screw extruder.

  15. 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.

  16. Production of Bio-omega-3 eggs through the supplementation of extruded flaxseed meal in hen diet.

    Science.gov (United States)

    Imran, Muhammad; Anjum, Faqir Muhammad; Nadeem, Muhammad; Ahmad, Nazir; Khan, Muhammad Kamran; Mushtaq, Zarina; Hussain, Shahzad

    2015-10-09

    The full-fat flaxseed meal has obtained relatively new flourished concept as staple chicken feedstuff for the production of designer eggs. However, unprocessed flaxseed also encloses well documented anti-nutritional factors which are associated with growth depression of laying hens. The present research work was carried out to evaluate the impact of full-fat extruded flaxseed meal supplemented diets on productivity performance of hens and production of modified ω-3 fatty acids-enriched eggs. The full-fat flaxseed meal was extruded at barrel exit temperature (140 °C), screw speed (160 rpm) and feed rate (25 kg/h) for reduction of anti-nutritional compounds. One hundred and sixty, Babcock hens (age 24 weeks old) were selected at random from a large flock and ten hens were placed in each of 16 wire-mesh pens. The experimental diets prepared by supplementation of extruded flaxseed at 10%, 20% and 30% level were fed to hens along with control. The extruded flaxseed contained 86% and 76% less hydrocyanic compounds and tannin, respectively than the initial material. The hens fed with control diet consumed more feed, possessed heavy body weight and showed higher egg production as compared to hens fed on extruded flaxseed supplemented diets. The loss in body weight and egg production was recorded less for hens fed on 10% extruded flaxseed supplemented diets as compared to those fed on 30% extruded flaxseed supplemented diets. None of the experimental diets resulted in significant increase or decrease the total lipids and cholesterol content in egg yolk of hens. The extruded flaxseed supplemented diets resulted in a significant improvement of α-linolenic and docosahexaenoic acid in egg yolk with a concomitant reduction in arachidonic acid. The sensory scores were assigned higher to control eggs. Increasing level of extruded flaxseed in experimental diets decreased the scores for all sensory attributes of eggs. The present study suggested that extruded flaxseed meal up to

  17. Physical and functional properties of arrowroot starch extrudates.

    Science.gov (United States)

    Jyothi, A N; Sheriff, J T; Sajeev, M S

    2009-03-01

    Arrowroot starch, a commercially underexploited tuber starch but having potential digestive and medicinal properties, has been subjected to extrusion cooking using a single screw food extruder. Different levels of feed moisture (12%, 14%, and 16%) and extrusion temperatures (140, 150, 160, 170, 180, and 190 degrees C) were used for extrusion. The physical properties--bulk density, true density, porosity, and expansion ratio; functional properties such as water absorption index, water solubility index, oil absorption index, pasting, rheological, and textural properties; and in vitro enzyme digestibility of the extrudates were determined. The expansion ratio of the extrudates ranged from 3.22 to 6.09. The water absorption index (6.52 to 8.85 g gel/g dry sample), water solubility index (15.92% to 41.31%), and oil absorption index (0.50 to 1.70 g/g) were higher for the extrudates in comparison to native starch (1.81 g gel/g dry sample, 1.16% and 0.60 g/g, respectively). The rheological properties, storage modulus, and loss modulus of the gelatinized powdered extrudates were significantly lower (P extruded at higher feed moisture and lower extrusion temperature, whereas snap force and energy were higher at lower feed moisture and temperature. There was a significant decrease in the percentage digestibility of arrowroot starch (30.07% after 30 min of incubation with the enzyme) after extrusion (25.27% to 30.56%). Extrusion cooking of arrowroot starch resulted in products with very good expansion, color, and lower digestibility, which can be exploited for its potential use as a snack food.

  18. NH3-SCR on Cu, Fe and Cu + Fe exchanged beta and SSZ-13 catalysts: Hydrothermal aging and propylene poisoning effects

    International Nuclear Information System (INIS)

    Wang, Aiyong; Wang, Yilin; Walter, Eric D.; Washton, Nancy M.

    2017-01-01

    Cu, Fe and Cu + Fe ion exchanged Beta and SSZ-13 catalysts were prepared by solution ion exchange using commercial NH 4 /Beta, and NH 4 /SSZ-13 that was prepared in-house. To study hydrothermal aging effects, Beta supported catalysts were aged hydrothermally at 700 °C and SSZ-13 supported catalysts were aged at 750 °C. In order to reveal the effects of Fe addition in the co-exchanged catalysts, these catalysts were characterized by means of powder X-ray diffraction (XRD), N 2 adsorption-desorption, electron paramagnetic resonance (EPR), 27 Al-nuclear magnetic resonance ( 27 Al-NMR) and propylene coking followed with temperature programmed reaction (TPR), and further tested with standard NH 3 -SCR with and without the presence of propylene. Collectively, the catalyst characterizations and reaction testing indicated minor beneficial effects of Fe addition in Cu,Fe/Beta, where NH 3 -SCR activity, N 2 selectivity and hydrothermal stability were all slightly improved. In contrast, Fe addition did not show apparent beneficial effects in low-temperature SCR for the Cu,Fe/SSZ-13 case. In conclusion, at elevated reaction temperatures, however, the presence of Fe indeed considerably improved NO conversion and N 2 selectivity for the hydrothermally aged Cu,Fe/SSZ-13 catalyst in the presence of propylene.

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

    International Nuclear Information System (INIS)

    Iwami, K; Noda, T; Ishida, K; Umeda, N; Morishima, K; Nakamura, M

    2010-01-01

    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 μm by employing a nozzle of diameter 100 μm, and that of aspirated groove was 355 ± 10 μm using a 500 μm-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.

  20. 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.

  1. Acceptability and characterization of extruded pinto, navy and black beans.

    Science.gov (United States)

    Simons, Courtney W; Hall, Clifford; Tulbek, Mehmet; Mendis, Mihiri; Heck, Taylor; Ogunyemi, Samuel

    2015-08-30

    Consumption of dry beans has been relatively flat over the last decade. Creating new bean products may increase the consumption of beans and allow more consumers to obtain the health benefits of beans. In this study, pinto, navy and black beans were milled and the resulting flours extruded into puffs. Unflavored extruded puffs were evaluated by untrained panelists using a hedonic scale for appearance, flavor, texture and overall acceptability. The compositions of raw flours and extrudates were characterized. Sensory results indicated that all beans met or exceeded the minimum requirement for acceptability. Overall acceptability of navy and pinto beans was not significantly different, while acceptability of black bean puffs was significantly lower. Total protein (198-217 g kg(-1)) in extrudates was significantly different among the three beans. Total starch ranged from 398 to 406 g kg(-1) and was not significantly different. Resistant starch, total extractable lipid and raffinose contents were significantly reduced by extrusion. Extrusion did not affect crude fiber and phytic acid contents. The minimal effects on protein and fiber contents, the significant reduction in raffinose content and the acceptability of the unflavored extruded puffs support using various bean flours as ingredients in extruded puffed products. © 2014 Society of Chemical Industry.

  2. Instrumental and sensory properties of pea protein-fortified extruded rice snacks.

    Science.gov (United States)

    Philipp, Claudia; Buckow, Roman; Silcock, Pat; Oey, Indrawati

    2017-12-01

    Characteristic attributes of pea-protein fortified, extruded rice snacks were evaluated by mechanical, acoustic and descriptive sensory analysis. The addition of pea protein isolate (0 to 45% (w/w)) to rice flour and extruder screw speed strongly affected the expansion behaviour and therefore, textural attributes of extruded snack products. The sensory panel described the texture of highly expanded extrudates as crisp, while low expanded extrudates were perceived as hard, crunchy and non-crisp. Results of the instrumental and sensory analysis were compared and showed a high correlation between mechanical and sensory hardness (r=0.98), as well as acoustic and sensory crispness (r=0.88). However, poor and/or negative correlations between acoustic and sensory hardness and crunchiness were observed (r=-0.35 and -0.84, respectively). Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. 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.

  4. Flame spray synthesis of CoMo/Al2O3 hydrotreating catalysts

    DEFF Research Database (Denmark)

    Høj, Martin; Linde, Kasper; Hansen, Thomas Klint

    2011-01-01

    containing 16wt.% Mo (atomic ratio Co/Mo=1/3), which did not contain crystalline MoO3 and only small amounts of CoAl2O4. The hydrotreating activity was approximately 75% of that of commercial cobalt molybdenum catalysts prepared by wet impregnation of pre-shaped alumina extrudates. Since the commercial...... obtained consisted mostly of γ-Al2O3 with some CoAl2O4, as evidenced by X-ray diffraction (XRD) and UV–vis spectroscopy. Bulk MoO3 was not detected by XRD, except at the highest molybdenum content (32wt.%) and in the unsupported sample, indicating that molybdenum is well dispersed on the surface.......After activation by sulfidation the activity of the catalysts were measured for the three hydrotreating reactions hydrodesulfurization, hydrodenitrogenation and hydrogenation using a model oil containing dibenzothiophene, indole and naphthalene in n-heptane solution. The best catalyst was the FSP-produced material...

  5. The nutritional properties of extruded and non-extruded corn fiber isolate.

    Science.gov (United States)

    Artz, W E; Warren, C C; Erdman, J W; Villota, R

    1990-01-01

    The feed efficiency and selected organ weights of rats fed diets containing 3 or 7% corn fiber, extruded corn fiber or silica were compared to rats fed a fiber-free diet. No significant differences were found in feed efficiency, spleen, lung or liver weights for any of the treatments relative to the fiber-free control diet.

  6. Real-Time Quantitative Operando Raman Spectroscopy of a CrOx/Al2O3 Propane Dehydrogenation Catalyst in a Pilot-Scale Reactor

    NARCIS (Netherlands)

    Sattler, Jesper J. H. B.; Mens, Ad M.; Weckhuysen, Bert M.

    2014-01-01

    Combined operando UV/vis-Raman spectroscopy has been used to study the deactivation of CrOx/Al2O3 catalyst extrudates in a pilot scale propane dehydrogenation reactor. For this purpose, UV/vis and Raman optical fiber probes have been designed, constructed and tested. The light absorption measured by

  7. Insight into the effects of different ageing protocols on Rh/Al{sub 2}O{sub 3} catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Baohuai [Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, 100084 Beijing (China); Ran, Rui, E-mail: ranr@tsinghua.edu.cn [Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, 100084 Beijing (China); Cao, Yidan; Wu, Xiaodong; Weng, Duan [Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, 100084 Beijing (China); Fan, Jun [The Administrative Center for China' s Agenda 21, 100038 Beijing (China); Wu, Xueyuan [Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, 100084 Beijing (China)

    2014-07-01

    In this work, a catalyst of Rh loaded on Al{sub 2}O{sub 3} 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/Al{sub 2}O{sub 3} samples were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) method, CO-chemisorption, H{sub 2}-temperature programmed reduction (H{sub 2}-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 N{sub 2} aged and the H{sub 2} 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 N{sub 2} and the H{sub 2} 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 Al{sub 2}O{sub 3} 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.

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

    International Nuclear Information System (INIS)

    Hanna, M.A.; Chinnaswamy, R.; Gray, D.R.; Miladinov, V.D.

    1997-01-01

    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

  9. Lycopene bioaccessibility and starch digestibility for extruded snacks enriched with tomato derivatives.

    Science.gov (United States)

    Dehghan-Shoar, Zeinab; Mandimika, Tafadzwa; Hardacre, Allan K; Reynolds, Gordon W; Brennan, Charles S

    2011-11-23

    To improve the nutritional value of energy-dense extruded snacks, corn grits were replaced with tomato paste and/or tomato skin powder at ratios of 5, 10, and 20% and extruded to make expanded snack foodlike products. Using a model digestion system, lycopene bioaccessibility and uptake from the snacks into Caco-2 cells were determined. The digestibility of the starch, the main nutrient component of the snacks, was also investigated. While extrusion cooking reduced the lycopene content of the snacks, the proportion of bioaccessible lycopene increased. Lycopene uptake by the Caco-2 cells from the extruded snacks exceeded that of the control in which the lycopene was not extruded, by 5% (p snacks varied depending on the type of tomato derivative and its concentration. Optimization of the extrusion cooking process and the ingredients can yield functional extruded snack products that contain bioavailable lycopene.

  10. Parametric analysis and design of a screw extruder for slightly non-Newtonian (pseudoplastic materials

    Directory of Open Access Journals (Sweden)

    J.I. Orisaleye

    2018-04-01

    Full Text Available Extruders have found application in the food, polymer and pharmaceutical industries. Rheological characteristics of materials are important in the specification of design parameters of screw extruders. Biopolymers, which consist of proteins, nucleic acids and polysaccharides, are shear-thinning (pseudoplastic within normal operating ranges. However, analytical models to predict and design screw extruders for non-Newtonian pseudoplastic materials are rare. In this study, an analytical model suitable to design a screw extruder for slightly non-Newtonian materials was developed. The model was used to predict the performance of the screw extruder while processing materials with power law indices slightly deviating from unity (the Newtonian case. Using non-dimensional analysis, the effects of design and operational parameters were investigated. Expressions to determine the optimum channel depth and helix angle were also derived. The model is capable of predicting the performance of the screw extruder within the range of power law indices considered (1/2⩽n⩽1. The power law index influences the choice of optimum channel depth and helix angle of the screw extruder. Keywords: Screw extruder, Slightly non-Newtonian, Shear-thinning, Pseudoplastic, Biopolymer, Power law

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

    International Nuclear Information System (INIS)

    Coverdell, B.L.

    1995-09-01

    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

  12. Use of Red Cactus Pear (Opuntia ficus-indica Encapsulated Powder to Pigment Extruded Cereal

    Directory of Open Access Journals (Sweden)

    Martha G. Ruiz-Gutiérrez

    2017-01-01

    Full Text Available Encapsulated powder of the red cactus pear is a potential natural dye for the food industry and a known antioxidant. Although the use of this powder is possible, it is not clear how it alters food properties, thus ensuing commercial acceptability. The aim of this study was to evaluate the effect of encapsulated powder of the red cactus pear on the physicochemical properties of extruded cereals. The powder was mixed (2.5, 5.0, and 7.5% w/w with maize grits and extruded (mix moisture 22%, temperature 100°C, and screw speed 325 rpm. The physical, chemical, and sensory characteristics of the extruded cereal were evaluated; extruded cereal without encapsulated powder was used as a control. All cereal extrudates pigmented with the encapsulated powder showed statistically significant differences (P<0.05 in expansion, water absorption, color, density, and texture compared to the control. The encapsulated powder had a positive effect on expansion and water absorption indices, as well as color parameters, but a negative effect on density and texture. Extruded cereal properties were significantly (P<0.05 correlated. Sensorially, consumers accepted the extruded cereal with a lower red cactus pear powder content (2.5% w/w, because this presented characteristics similar to extruded cereal lacking pigment.

  13. Microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chaoyong [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); Pan, Fusheng, E-mail: fspan@cqu.edu.cn [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Chongqing Academy of Science and Technology, Chongqing 401123 (China); Zhang, Lei; Pan, Hucheng; Song, Kai; Tang, Aitao [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China)

    2017-01-01

    In this study, as-extruded Mg-Sr alloys were studied for orthopedic application, and the microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys were investigated by optical microscopy, scanning electron microscopy with an energy dispersive X-ray spectroscopy, X-ray diffraction, tensile and compressive tests, immersion test, electrochemical test and cytotoxicity test. The results showed that as-extruded Mg-Sr alloys were composed of α-Mg and Mg{sub 17}Sr{sub 2} phases, and the content of Mg{sub 17}Sr{sub 2} phases increased with increasing Sr content. As-extruded Mg-Sr alloy with 0.5 wt.% Sr was equiaxed grains, while the one with a higher Sr content was long elongated grains and the grain size of the long elongated grains decreased with increasing Sr content. Tensile and compressive tests showed an increase of both tensile and compressive strength and a decrease of elongation with increasing Sr content. Immersion and electrochemical tests showed that as-extruded Mg-0.5Sr alloy exhibited the best anti-corrosion property, and the anti-corrosion property of as-extruded Mg-Sr alloys deteriorated with increasing Sr content, which was greatly associated with galvanic couple effect. The cytotoxicity test revealed that as-extruded Mg-0.5Sr alloy did not induce toxicity to cells. These results indicated that as-extruded Mg-0.5Sr alloy with suitable mechanical properties, corrosion resistance and good cytocompatibility was potential as a biodegradable implant for orthopedic application. - Highlights: • Biodegradable as-extruded Mg-Sr alloys were fabricated. • Microstructure of alloys changed with increasing Sr content. • Mechanical properties of alloys could be controlled by adjusting the Sr content. • Corrosion properties of alloys decreased with increasing Sr content. • As-extruded Mg-0.5Sr alloy was potential for orthopedic application.

  14. Quality improvement of melt extruded laminar systems using mixture design.

    Science.gov (United States)

    Hasa, D; Perissutti, B; Campisi, B; Grassi, M; Grabnar, I; Golob, S; Mian, M; Voinovich, D

    2015-07-30

    This study investigates the application of melt extrusion for the development of an oral retard formulation with a precise drug release over time. Since adjusting the formulation appears to be of the utmost importance in achieving the desired drug release patterns, different formulations of laminar extrudates were prepared according to the principles of Experimental Design, using a design for mixtures to assess the influence of formulation composition on the in vitro drug release from the extrudates after 1h and after 8h. The effect of each component on the two response variables was also studied. Ternary mixtures of theophylline (model drug), monohydrate lactose and microcrystalline wax (as thermoplastic binder) were extruded in a lab scale vertical ram extruder in absence of solvents at a temperature below the melting point of the binder (so that the crystalline state of the drug could be maintained), through a rectangular die to obtain suitable laminar systems. Thanks to the desirability approach and a reliability study for ensuring the quality of the formulation, a very restricted optimal zone was defined within the experimental domain. Among the mixture components, the variation of microcrystalline wax content played the most significant role in overall influence on the in vitro drug release. The formulation theophylline:lactose:wax, 57:14:29 (by weight), selected based on the desirability zone, was subsequently used for in vivo studies. The plasma profile, obtained after oral administration of the laminar extruded system in hard gelatine capsules, revealed the typical trend of an oral retard formulation. The application of the mixture experimental design associated to a desirability function permitted to optimize the extruded system and to determine the composition space that ensures final product quality. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. [Significance of extruded feeds for trout nutrition and water protection].

    Science.gov (United States)

    Steffens, W

    1993-01-01

    Extruded feeds exhibit an improved starch digestibility and are more firmly bound due to the almost complete gelatinization of the starch. This results in fewer fines and longer water stability than pelleted feeds. Extruded pellets also have the advantage that they can soak up more oil than a conventional pellet. It is therefore possible to increase the maximum oil content to more than 20%. On the other hand extruding feeds is more expensive than steam pelleting. Gelatinized starch is a useful energy source in trout diets helping to reduce feed conversion ratios. Proportions up to 35-40% in the diet are tolerable. Using high dietary levels of both gelatinized starch and oil the non-protein energy of feed may be increased and thus a protein-sparing effect results. High-energy diets enable to reduce excretion of faeces and of nitrogen via gills. In addition a decrease of phosphorus level in feeds and thus of phosphorus excretion by fish is possible. Extruded high-energy diets therefore make a contribution to improve water quality.

  16. 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 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 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 glycerol...... using focused ion bean (FIB) milling allowed to acquire high resolution images of the Ni and Fe nanoparticles on ɣ-Al2O3, which is particularly challenging due to the crystalline nature of this support. Distinct regions of the egg-shell catalyst were analyzed through scanning TEM (STEM) and TEM...

  17. Antioxidant potential and quality characteristics of vegetable-enriched corn-based extruded snacks.

    Science.gov (United States)

    Bisharat, G I; Lazou, A E; Panagiotou, N M; Krokida, M K; Maroulis, Z B

    2015-07-01

    Phenolic content, antioxidant activity and sensory characteristics of vegetable-enriched extrudates were investigated as a result of extrusion conditions, including extrusion temperature (140-180 °C), screw rotation speed (150-250 rpm) and feed moisture content (14-19 % w.b.). Broccoli flour and olive paste was used in mixtures with corn flour at a ratio of 4 to 10 % (broccoli/corn) and 4 to 8 % (olive paste/corn). A simple power model was developed for the prediction of phenolic content and antioxidant activity of extrudates by extrusion conditions and feed composition. Phenolic content and antioxidant activity of broccoli enriched extrudates increased with extrusion temperature and broccoli addition and decreased with feed moisture content. The antioxidant activity of olive paste extrudates increased with material ratio and decreased with feed moisture content and screw rotation. Sensory porosity, homogenous structure, crispness, cohesiveness and melting decreased with feed moisture content, while the latter increased the mealy flavor and hardness of extrudates. Acceptable snacks containing broccoli flour or olive paste can be produced by selecting the appropriate process conditions.

  18. THE MODELING OF COUNTER-ROTATING TWIN-SCREW EXTRUDERS AS REACTORS FOR SINGLE-COMPONENT REACTIONS

    NARCIS (Netherlands)

    GANZEVELD, KJ; CAPEL, JE; VANDERWAL, DJ; JANSSEN, LPBM

    Numerical models are useful to study the behaviour of the extruder as a polymerization reactor. With a correct numerical model a theoretical analysis of the influence of several reaction and extruder parameters can be made, the limitations of the use of the extruder reactor can be determined and the

  19. Effects of extrusion variables on the properties of waxy hulless barley extrudates.

    Science.gov (United States)

    Köksel, Hamit; Ryu, Gy-Hyung; Başman, Arzu; Demiralp, Hande; Ng, Perry K W

    2004-02-01

    The objective of this research was to investigate the extrudability of waxy hulless barley flour under various extrusion conditions. Waxy hulless barley flour was processed in a laboratory-scale corotating twin-screw extruder with different levels of feed moisture content (22.3, 26.8, and 30.7%) and die temperature (130, 150, and 170 degrees C) to develop a snack food with high beta-glucan content. The effects of extrusion condition variables (screw configuration, moisture, and temperature) on the system variables (pressure and specific mechanical energy), the extrudate physical properties (sectional expansion index, bulk density), starch gelatinization, pasting properties (cold peak viscosity, trough viscosity, and final viscosity), and beta-glucan contents were determined. Results were evaluated by using response surface methodology. Increased extrusion temperature and feed moisture content resulted in decreases in exit die pressure and specific mechanical energy values. For extrudates extruded under low shear screw configuration (LS), increased barrel temperature decreased sectional expansion index (SEI) values at both low and high moisture contents. The feed moisture seems to have an inverse relationship with SEI over the range studied. Bulk density was higher at higher moisture contents, for both low and high barrel temperatures, for samples extruded under high shear screw configuration (HS) and LS. Cold peak viscosities (CV) were observed in all samples. The CV increased with the increase in extrusion temperature and feed moisture content. Although beta-glucan contents of the LS extrudates were comparable to that of barley flour sample, HS samples had generally lower beta-glucan contents. The extrusion cooking technique seems to be promising for the production of snack foods with high beta-glucan content, especially using LS conditions.

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

    International Nuclear Information System (INIS)

    Oda, Y.; Azuma, K.; Onozuka, M.; Kasai, S.; Hasegawa, K.

    1995-01-01

    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.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Y. [Mitsubishi Heavy Industries Ltd., Kobe (Japan); Azuma, K. [Mitsubishi Heavy Industries Ltd., Kobe (Japan); Onozuka, M. [Mitsubishi Heavy Industries Ltd., Kobe (Japan); Kasai, S. [Japan Atomic Energy Research Inst., Ibaraki (Japan); Hasegawa, K. [Japan Atomic Energy Research Inst., Ibaraki (Japan)

    1995-12-31

    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.).

  2. Apically extruded dentin debris by reciprocating single-file and multi-file rotary system.

    Science.gov (United States)

    De-Deus, Gustavo; Neves, Aline; Silva, Emmanuel João; Mendonça, Thais Accorsi; Lourenço, Caroline; Calixto, Camila; Lima, Edson Jorge Moreira

    2015-03-01

    This study aims to evaluate the apical extrusion of debris by the two reciprocating single-file systems: WaveOne and Reciproc. Conventional multi-file rotary system was used as a reference for comparison. The hypotheses tested were (i) the reciprocating single-file systems extrude more than conventional multi-file rotary system and (ii) the reciprocating single-file systems extrude similar amounts of dentin debris. After solid selection criteria, 80 mesial roots of lower molars were included in the present study. The use of four different instrumentation techniques resulted in four groups (n = 20): G1 (hand-file technique), G2 (ProTaper), G3 (WaveOne), and G4 (Reciproc). The apparatus used to evaluate the collection of apically extruded debris was typical double-chamber collector. Statistical analysis was performed for multiple comparisons. No significant difference was found in the amount of the debris extruded between the two reciprocating systems. In contrast, conventional multi-file rotary system group extruded significantly more debris than both reciprocating groups. Hand instrumentation group extruded significantly more debris than all other groups. The present results yielded favorable input for both reciprocation single-file systems, inasmuch as they showed an improved control of apically extruded debris. Apical extrusion of debris has been studied extensively because of its clinical relevance, particularly since it may cause flare-ups, originated by the introduction of bacteria, pulpal tissue, and irrigating solutions into the periapical tissues.

  3. Ethanol fermentation of HTST extruded rye grain by bacteria and yeasts

    Energy Technology Data Exchange (ETDEWEB)

    Czarnecki, Z [Univ. of Agriculture, Poznan (Poland). Inst. of Food Technology; Nowak, J [Univ. of Agriculture, Poznan (Poland). Inst. of Food Technology

    1997-09-01

    High temperature extrusion cooking of rye was used as a pretreatment for ethanol fermentation, and yeasts and bacteria were compared for their fermentation rates. Extrusion cooking caused, on average, a 7.5% increase in ethanol yield in comparison to autoclaved samples. The best results were achieved for grain with a moisture of 21-23% which was extruded at temperatures of 160-180 C. Extrusion decreased the relative viscosity of rye grain water extracts, so it was possible to mash it without {alpha}-amylase. The efficiency of fermentation of extruded rye without Termamyl was equal to that of autoclaved and traditionally mashed rye (using {alpha}-amylase). The rate of fermentation of extruded rye grain by Zymomonas was higher during the first stage, but the final ethanol yield was similar for the bacterium and the yeast. Through both microorganisms gave good quality distillates, the concentration of compounds other than ethanol achieved from extruded rye mashes, which were fermented by Z. mobilis, was five times lower than for yeasts. (orig.)

  4. Extrudable polymer-polymer composites based on ultra-high molecular weight polyethylene

    Science.gov (United States)

    Panin, S. V.; Kornienko, L. A.; Alexenko, V. O.; Buslovich, D. G.; Dontsov, Yu. V.

    2017-12-01

    Mechanical and tribotechnical characteristics of polymer-polymeric composites of UHMWPE are studied with the aim of developing extrudable, wear-resistant, self-lubricant polymer mixtures for Additive Manufacturing (AM). The motivation of the study is their further application as feedstocks for 3D printing. Blends of UHMWPE with graft- and block copolymers of low-density polyethylene (HDPE-g-VTMS, HDPE-g-SMA, HDPE-b-EVA), polypropylene (PP), block copolymers of polypropylene and polyamide with linear low density polyethylene (PP-b-LLDPE, PA-b-LLDPE), as well as cross-linked polyethylene (PEX-b), are examined. The choice of compatible polymer components for an ultra- high molecular weight matrix for increasing processability (extrudability) is motivated by the search for commercially available and efficient additives aimed at developing wear-resistant extrudable polymer composites for additive manufacturing. The extrudability, mechanical properties and wear resistance of UHMWPE-based polymer-polymeric composites under sliding friction with different velocities and loads are studied.

  5. Physical and functional characteristics of extrudates prepared from fenugreek and oats

    Directory of Open Access Journals (Sweden)

    Sajad Ahmad Wani

    2016-12-01

    Full Text Available This study was conducted to investigate the effect of fenugreek seed powder (FSP and oat flour (OF on the physical and functional properties of extruded snack product such as bulk density (BD, hardness (HD, lateral expansion (LE, water absorption index (WAI and water solubility index (WSI using response surface methodology. All the properties were found to be significantly (p < 0.05 affected by proportion of FSP and OF. Results indicated that with the increase in the FSP content, an increase in the values of BD, HD, WAI and WSI was noticed, whereas negative effect of FSP on LE was observed. Results showed negative effect of OF on HD and WSI and an increased effect on BD, LE and WAI of the extruded product. Numerical optimization results showed that a mixture of 2% FSP and 6% OF had higher preference levels for parameters of physical and functional characteristics and could be extruded to produce acceptable quality extrudates.

  6. Chemical modification and blending of polymers in an extruder reactor

    International Nuclear Information System (INIS)

    Prut, Eduard V; Zelenetskii, Alexandr N

    2001-01-01

    Chemical modification and blending of polymers in an extruder reactor are discussed. Relationships between the parameters affecting the reaction kinetics, viz., mixing time, duration of a chemical reaction and the residence time of the system in the extruder reactor, and the structure of the materials produced are analysed. The mechanisms of (i) grafting of low-molecular-mass compounds onto polymers; (ii) reactions between terminal groups of different polymers and (iii) transesterification and interchange reactions are considered. The factors affecting the mechanism of dynamic vulcanisation and the properties of thermoplastic elastomers are identified. Solid-phase reactions of polysaccharides in an extruder are discussed. The priority aspects of studies on the chemical modification and blending of polymers are noted. The bibliography includes 90 references.

  7. Control of lipid oxidation in extruded salmon jerky snacks.

    Science.gov (United States)

    Kong, Jian; Perkins, L Brian; Dougherty, Michael P; Camire, Mary Ellen

    2011-01-01

    A shelf-life study was conducted to evaluate the effect of antioxidants on oxidative stability of extruded jerky-style salmon snacks. Deterioration of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) due to lipid oxidation is a major concern for this healthy snack. A control jerky with no added antioxidants and 4 jerkies with antioxidants (rosemary, mixed tocopherols, tertiary butylhydroquinone, and ascorbyl palmitate) added as 0.02% of the lipid content were extruded in duplicate in a Coperion ZSK-25 twin screw extruder. Salmon jerkies from each formulation were placed in 3 mil barrier pouches, flushed with nitrogen, and stored at 35 °C and 75% relative humidity. Lipid oxidation was evaluated as by peroxide value and malonaldehyde content. Other chemical analyses included total fatty acid composition, lipid content, moisture, water activity, pH, and salt. Astaxanthin and CIE L*, a*, b* color were also analyzed at 4-wk intervals. Rosemary inhibited peroxide formation better than did other antioxidants at week 8; no treatment inhibited malonaldehyde levels. All jerkies had lower astaxanthin levels after 8 wk, but rosemary-treated jerky had higher pigment concentrations than did the control at weeks 4 and 8. Protection of omega-3 lipids in these extruded jerkies must be improved to offer consumers a convenient source of these healthful lipids. Practical Application: Salmon flesh can be extruded to produce a jerky that provides 410 mg of omega-3 lipids per serving. Natural antioxidants such as rosemary should be added at levels over 0.02% of the lipid content to help control lipid oxidation. Astaxanthin and CIE a* values correlated well with lipid stability and could be used to monitor quality during storage if initial values are known.

  8. 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.

  9. Microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys.

    Science.gov (United States)

    Zhao, Chaoyong; Pan, Fusheng; Zhang, Lei; Pan, Hucheng; Song, Kai; Tang, Aitao

    2017-01-01

    In this study, as-extruded Mg-Sr alloys were studied for orthopedic application, and the microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys were investigated by optical microscopy, scanning electron microscopy with an energy dispersive X-ray spectroscopy, X-ray diffraction, tensile and compressive tests, immersion test, electrochemical test and cytotoxicity test. The results showed that as-extruded Mg-Sr alloys were composed of α-Mg and Mg 17 Sr 2 phases, and the content of Mg 17 Sr 2 phases increased with increasing Sr content. As-extruded Mg-Sr alloy with 0.5wt.% Sr was equiaxed grains, while the one with a higher Sr content was long elongated grains and the grain size of the long elongated grains decreased with increasing Sr content. Tensile and compressive tests showed an increase of both tensile and compressive strength and a decrease of elongation with increasing Sr content. Immersion and electrochemical tests showed that as-extruded Mg-0.5Sr alloy exhibited the best anti-corrosion property, and the anti-corrosion property of as-extruded Mg-Sr alloys deteriorated with increasing Sr content, which was greatly associated with galvanic couple effect. The cytotoxicity test revealed that as-extruded Mg-0.5Sr alloy did not induce toxicity to cells. These results indicated that as-extruded Mg-0.5Sr alloy with suitable mechanical properties, corrosion resistance and good cytocompatibility was potential as a biodegradable implant for orthopedic application. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. THE DESIGN, FABRICATION AND PRELIMINARY TESTING OF AN INDIGENOUS SINGLE SCREW EXTRUDER

    Directory of Open Access Journals (Sweden)

    FOLASAYO T. FAYOSE

    2017-10-01

    Full Text Available Developing countries including Nigeria have become dumping grounds of unserviceable and broken down imported machineries because of poor adaptation. Detailed study and design of machines to suit local conditions will prevent poor adaptation of imported machines and high initial costs. In this study, a single screw starch extruder was designed, fabricated and tested using locally available materials. The extruder is the dry type and it has 27.12 kg/s capacity, a compression ratio of 4.5: 1 and is powered by a 5.5 kW electric motor. It consists of a hopper, feeding screw, extruder screw rotating in a barrel and variable die, all made of stainless steel. A unit of the machine costs N 470, 390.00.00 as at April 2015. When used to process cassava flour, a maximum temperature of 114°C was attained through viscous dissipation, up to an actual screw speed of 98.96 rpm (1.65 Hz and extruder efficiency of 64%. Barrel temperature varied directly with extrusion time in a polynomial trend while actual extruder screw speed and efficiency varied inversely with extrusion time and it is best fitted with a polynomial trend.

  11. Quality evaluation of millet-soy blended extrudates formulated through linear programming.

    Science.gov (United States)

    Balasubramanian, S; Singh, K K; Patil, R T; Onkar, Kolhe K

    2012-08-01

    Whole pearl millet, finger millet and decorticated soy bean blended (millet soy) extrudates formulations were designed using a linear programming (LP) model to minimize the total cost of the finished product. LP formulated composite flour was extruded through twin screw food extruder at different feed rate (6.5-13.5 kg/h), screw speed (200-350 rpm, constant feed moisture (14% wb), barrel temperature (120 °C) and cutter speed (15 rpm). The physical, functional, textural and pasting characteristics of extrudates were examined and their responses were studied. Expansion index (2.31) and sectional expansion index (5.39) was found to be was found maximum for feed rate and screw speed combination 9.5 kg/h and 250 rpm. However, density (0.25 × 10(-3) g/mm(3)) was maximum for 9.5 kg/h and 300 rpm combination. Maximum color change (10.32) was found for 9.5 kg/h feed rate and 200 rpm screw speed. The lower hardness was obtained for the samples extruded at lowest feed rate (6.5 kg/h) for all screw speed and feed rate at 9.5 kg/h for 300-350 rpm screw speed. Peak viscosity decreases with all screw speed of 9.5 kg/h feed rate.

  12. Properties of whey protein isolates extruded under acidic and alkaline conditions.

    Science.gov (United States)

    Onwulata, C I; Isobe, S; Tomasula, P M; Cooke, P H

    2006-01-01

    Whey proteins have wide acceptance and use in many products due to their beneficial nutritional properties. To further increase the amount of whey protein isolates (WPI) that may be added to products such as extruded snacks and meats, texturization of WPI is necessary. Texturization changes the folding of globular proteins to improve interaction with other ingredients and create new functional ingredients. In this study, WPI pastes (60% solids) were extruded in a twin-screw extruder at 100 degrees C with 4 pH-adjusted water streams: acidic (pH 2.0 +/- 0.2) and alkaline (pH 12.4 +/- 0.4) streams from 2 N HCl and 2 N NaOH, respectively, and acidic (pH 2.5 +/- 0.2) and alkaline (pH 11.5 +/- 0.4) electrolyzed water streams; these were compared with WPI extruded with deionized water. The effects of water acidity on WPI solubility at pH 7, color, microstructure, Rapid Visco Analyzer pasting properties, and physical structure were determined. Alkaline conditions increased insolubility caused yellowing and increased pasting properties significantly. Acidic conditions increased solubility and decreased WPI pasting properties. Subtle structural changes occurred under acidic conditions, but were more pronounced under alkaline conditions. Overall, alkaline conditions increased denaturation in the extruded WPI resulting in stringy texturized WPI products, which could be used in meat applications.

  13. A desktop 3D printer with dual extruders to produce customised electronic circuitry

    Science.gov (United States)

    Butt, Javaid; Onimowo, Dominic Adaoiza; Gohrabian, Mohammed; Sharma, Tinku; Shirvani, Hassan

    2018-03-01

    3D printing has opened new horizons for the manufacturing industry in general, and 3D printers have become the tools for technological advancements. There is a huge divide between the pricing of industrial and desktop 3D printers with the former being on the expensive side capable of producing excellent quality products and latter being on the low-cost side with moderate quality results. However, there is a larger room for improvements and enhancements for the desktop systems as compared to the industrial ones. In this paper, a desktop 3D printer called Prusa Mendel i2 has been modified and integrated with an additional extruder so that the system can work with dual extruders and produce bespoke electronic circuits. The communication between the two extruders has been established by making use of the In-Chip Serial Programming port on the Arduino Uno controlling the printer. The biggest challenge is to control the flow of electric paint (to be dispensed by the new extruder) and CFD (Computational Fluid Dynamics) analysis has been carried out to ascertain the optimal conditions for proper dispensing. The final product is a customised electronic circuit with the base of plastic (from the 3D printer's extruder) and electronic paint (from the additional extruder) properly dispensed to create a live circuit on a plastic platform. This low-cost enhancement to a desktop 3D printer can provide a new prospect to produce multiple material parts where the additional extruder can be filled with any material that can be properly dispensed from its nozzle.

  14. Deactivation and regeneration of refinery catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.

    1979-08-01

    A discussion covers the mechanisms of catalyst aging, poisoning, coke deposition, and metals deposition; feedstock pretreatment to extend catalyst life; the effects of operating conditions; the effects of catalyst composition and structure on its stability; nonchemical deactivation processes; and methods of catalyst regeneration, including coke burn-off and solvent extraction.

  15. Erosion in extruder flow

    Science.gov (United States)

    Kaufman, Miron; Fodor, Petru S.

    A detailed analysis of the fluid flow in Tadmor's unwound channel model of the single screw extruder is performed by combining numerical and analytical methods. Using the analytical solution for the longitudinal velocity field (in the limit of zero Reynolds number) allows us to devote all the computational resources solely for a detailed numerical solution of the transversal velocity field. This high resolution 3D model of the fluid flow in a single-screw extruder allows us to identify the position and extent of Moffatt eddies that impede mixing. We further consider the erosion of particles (e.g. carbon-black agglomerates) advected by the polymeric flow. We assume a particle to be made of primary fragments bound together. In the erosion process a primary fragment breaks out of a given particle. Particles are advected by the laminar flow and they disperse because of the shear stresses imparted by the fluid. The time evolution of the numbers of particles of different sizes is described by the Bateman coupled differential equations used to model radioactivity. Using the particle size distribution we compute an entropic fragmentation index which varies from 0 for a monodisperse system to 1 for an extreme poly-disperse system.

  16. Diclofenac sodium sustained release hot melt extruded lipid matrices.

    Science.gov (United States)

    Vithani, K; Cuppok, Y; Mostafa, S; Slipper, I J; Snowden, M J; Douroumis, D

    2014-08-01

    Sustained release diclofenac sodium (Df-Na) solid lipid matrices with Compritol® 888 ATO were developed in this study. The drug/lipid powders were processed via cold and hot melt extrusion at various drug loadings. The influence of the processing temperatures, drug loading and the addition of excipients on the obtained dissolution rates was investigated. The physicochemical characterization of the extruded batches showed the existence of crystalline drug in the extrudates with a small amount being solubilized in the lipid matrix. The drug content and uniformity on the tablet surface were also investigated by using energy dispersive X-ray microanalysis. The dissolution rates were found to depend on the actual Df-Na loading and the nature of the added excipients, while the effect of the processing temperatures was negligible. The dissolution mechanism of all extruded formulations followed Peppas-Korsemeyer law, based on the estimated determination coefficients and the dissolution constant rates, indicating drug diffusion from the lipid matrices.

  17. Effect of Different Levels of Extruded Soybean and Avizyme Enzyme on Broiler Performance

    Directory of Open Access Journals (Sweden)

    H Nasiri Mogadam

    2012-01-01

    Full Text Available An experiment was conducted to examine the effect of different levels of extruded soybean and enzyme on broiler performance. In a completely randomized design with 2×3 factorial arrangement, 480 one day-old, Ross broiler chickens were divided into 40 groups, 12 chicks per pen. Treatments were consisting of combination of four levels of extruded soybean (0.0, 5.0, 10.0 and 15.0 % and two levels of enzyme (0.0 and 500 g per ton. Different levels of extruded soybean and enzyme had no significant effect on blood factors such as cholesterol, triglyceride and the weight of liver and heart. The usage of extruded soybean and enzyme showed significantly higher weight gain and better feed conversion (p

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

    Science.gov (United States)

    Logani, Ajay; Shah, Naseem

    2008-01-01

    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. 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. The Kruskal-Wallis nonparametric test and Mann-Whitney U test were applied to determine if significant differences existed among the groups ( PProTaper 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 ( PProTaper rotary extruded a significantly higher amount of debris than the ProFile.

  19. A Miniaturized Extruder to Prototype Amorphous Solid Dispersions: Selection of Plasticizers for Hot Melt Extrusion.

    Science.gov (United States)

    Lauer, Matthias E; Maurer, Reto; Paepe, Anne T De; Stillhart, Cordula; Jacob, Laurence; James, Rajesh; Kojima, Yuki; Rietmann, Rene; Kissling, Tom; van den Ende, Joost A; Schwarz, Sabine; Grassmann, Olaf; Page, Susanne

    2018-05-19

    Hot-melt extrusion is an option to fabricate amorphous solid dispersions and to enhance oral bioavailability of poorly soluble compounds. The selection of suitable polymer carriers and processing aids determines the dissolution, homogeneity and stability performance of this solid dosage form. A miniaturized extrusion device (MinEx) was developed and Hypromellose acetate succinate type L (HPMCAS-L) based extrudates containing the model drugs neurokinin-1 (NK1) and cholesterylester transfer protein (CETP) were manufactured, plasticizers were added and their impact on dissolution and solid-state properties were assessed. Similar mixtures were manufactured with a lab-scale extruder, for face to face comparison. The properties of MinEx extrudates widely translated to those manufactured with a lab-scale extruder. Plasticizers, Polyethyleneglycol 4000 (PEG4000) and Poloxamer 188, were homogenously distributed but decreased the storage stability of the extrudates. Stearic acid was found condensed in ultrathin nanoplatelets which did not impact the storage stability of the system. Depending on their distribution and physicochemical properties, plasticizers can modulate storage stability and dissolution performance of extrudates. MinEx is a valuable prototyping-screening method and enables rational selection of plasticizers in a time and material sparing manner. In eight out of eight cases the properties of the extrudates translated to products manufactured in lab-scale extrusion trials.

  20. Electron microscopic studies of natural gas oxidation catalyst – Effects of thermally accelerated aging on catalyst microstructure

    DEFF Research Database (Denmark)

    Honkanen, Mari; Hansen, Thomas Willum; Jiang, Hua

    2017-01-01

    Structural changes of PtPd nanoparticles in a natural gas oxidation catalyst were studied at elevated temperatures in air and low-oxygen conditions and in situ using environmental transmission electron microscopy (ETEM). The fresh catalyst shows

  1. Numerical study of internal flow in twin screw extruder and its mixing performance analysis

    International Nuclear Information System (INIS)

    Kim, Nak Soo; Kim, Hong Bum; Lee, Jae Wook

    2006-01-01

    We analyzed the non-Newtonian and non-isothermal flow in the melt conveying zone in co-rotating and counter-rotating screw extruder system with the commercial code, STAR-CD, and compared the mixing performance with respect to screw speed and rotating direction. The viscosity of fluid was described by power-law model. The dynamics of mixing was studied numerically by tracking the motion of particles in a twin screw extruder system. The extent of mixing was characterized in terms of the residence time distribution and average strain. The results showed that high screw speed decreases the residence time but increases the shear rate. Therefore higher screw speed increases the strain and has better mixing performance. Counter-rotating screw extruder system and co-rotating screw extruder has the similar shear rate with the same screw speed in spite of different rotating direction. However, the counter-rotating screw has good mixing performance, which is resulted from longer residence time than that of co-rotating screw extruder

  2. A two-stage fixed-bed reactor for direct hydrotreatment of volatiles from the hydropyrolysis of biomass: effect of catalyst temperature, pressure and catalyst ageing time on product characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Pindoria, R.V.; Megaritis, A.; Herod, A.A.; Kandiyoti, R. [Imperial College of Science, Technology and Medicine, London (United Kingdom). Dept. of Chemical Engineering and Chemical Technology

    1998-12-01

    This investigation involved the hydropyrolysis of biomass (eucalyptus globulus) and the immediate catalytic hydrocracking of pyrolytic oils in the second stage of the reactor. The effects of temperature, pressure and the catalyst ageing time on the final product tar have been studied using the catalyst Zeolite H-ZSM5. The catalytically hydrocracked tar/oil products were characterised and compared with the hydropyrolysis product from the first stage of the reactor to determine the effect of catalytic hydrocracking. The carbon deposition on the catalyst has been examined using thermogravimetric analysis. The tar yields after catalytic hydrocracking decreased with increasing pressure and temperature of the cracking stage. The tar yields at 10 bar pressure were greater than those at 40 bar pressure. The fresh zeolite catalyst trapped more than 40% of the product from the hydropyrolysis stage and TGA evidence indicated that this was not as carbon deposition but as volatiles trapped in the zeolite matrix. Reuse of the catalyst resulted in little more uptake of volatiles; however, extended use of the catalyst did not result in increased yields of liquid products but in increased production of light volatiles or gas. The H-ZSM5 catalyst appeared to act as a more active cracking catalyst rather than to promote hydrogenation or deoxygenation of the liquids produced in the hydropyrolysis stage. Characterisation of the liquids by SEC and UV fluorescence indicated that structural changes were relatively minor despite the significant changes in yields of liquids with process conditions. Available reaction routes do not appear to allow specific deoxygenation pathways to predominate without disintegration of parent molecules to lighter volatiles, under the conditions used here. 41 refs., 10 figs., 4 tabs.

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

    NARCIS (Netherlands)

    GANZEVELD, KJ; JANSSEN, LPBM

    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

  4. Physical, Textural, and Antioxidant Properties of Extruded Waxy Wheat Flour Snack Supplemented with Several Varieties of Bran.

    Science.gov (United States)

    Fleischman, Emily F; Kowalski, Ryan J; Morris, Craig F; Nguyen, Thuy; Li, Chongjun; Ganjyal, Girish; Ross, Carolyn F

    2016-09-28

    Wheat represents a ubiquitous commodity and although industries valorize 10% of wheat bran, most of this antioxidant-rich byproduct gets fed to livestock. The objective of this study was to incorporate wheat bran into an extruded snack. Bran samples from hard red spring, soft white club cv. Bruehl, and purple wheat lines were added to cv. Waxy-Pen wheat flour (Triticum aestivum L.) at replacement concentrations of 0%, 12.5%, 25%, and 37.5% (w/w; n = 10). Extrudates were evaluated for antioxidant capacity, color, and physical properties. Results showed that high fiber concentrations altered several pasting properties, reduced expansion ratios (P extrudates. Purple bran supplemented extrudates produced harder products compared to white and red bran treatments (P Extrudates produced with 37.5% (w/w) of each bran variety absorbed more water than the control with no added bran. The oxygen radical absorption capacity assay, expressed as Trolox Equivalents, showed that extrudates made with addition of red (37.5%) and purple (37.5%) bran had higher values compared to the other treatments; the control, red, and white bran treatments had less antioxidant activity after extrusion (P extrudates. Purple and red brans may serve as viable functional ingredients in extruded foods given their higher antioxidant activities. Future studies could evaluate how bran variety and concentration, extruded shape, and flavor influence consumer acceptance. © 2016 Institute of Food Technologists®

  5. 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.

  6. Defatted flaxseed meal incorporated corn-rice flour blend based extruded product by response surface methodology.

    Science.gov (United States)

    Ganorkar, Pravin M; Patel, Jhanvi M; Shah, Vrushti; Rangrej, Vihang V

    2016-04-01

    Considering the evidence of flaxseed and its defatted flaxseed meal (DFM) for human health benefits, response surface methodology (RSM) based on three level four factor central composite rotatable design (CCRD) was employed for the development of DFM incorporated corn - rice flour blend based extruded snack. The effect of DFM fortification (7.5-20 %), moisture content of feed (14-20 %, wb), extruder barrel temperature (115-135 °C) and screw speed (300-330 RPM) on expansion ratio (ER), breaking strength (BS), overall acceptability (OAA) score and water solubility index (WSI) of extrudates were investigated using central composite rotatable design (CCRD). Significant regression models explained the effect of considered variables on all responses. DFM incorporation level was found to be most significant independent variable affecting on extrudates characteristics followed by extruder barrel temperature and then screw rpm. Feed moisture content did not affect extrudates characteristics. As DFM level increased (7.5 % to 20 %), ER and OAA value decreased. However, BS and WSI values were found to increase with increase in DFM level. Based on the defined criteria for numerical optimization, the combination for the production of DFM incorporated extruded snack with desired sensory attributes was achieved by incorporating 10 % DFM (replacing rice flour in flour blend) and by keeping 20 % moisture content, 312 screw rpm and 125 °C barrel temperature.

  7. Enzymatic conversion of starch in twin-screw HTST-extruder

    Energy Technology Data Exchange (ETDEWEB)

    Hakulin, S; Linko, Y Y; Linko, P; Seiler, K; Seibel, W

    1983-12-01

    Wheat starch was liquefied to DE 25-30 employing heat stable ..cap alpha..-amylase and twin-screw Werner and Pfleiderer Continua 58 HTST-extruder. Most significant reduction in batch saccharification time was obtained when starch was liquefied as a slurry containing 60% water at 120/sup 0/C mass temperature, feed rate 1 500 g min/sup -1/, screw rotation rate 250 min/sup -1/, and 0.9% (w/w, d.s.) Novo Termamyl 120 L ..cap alpha..-amylase was added immediately after initiation of gelatinization in the extruder. Saccharification was carried out at 60/sup 0/C employing 0.36 (w/w, d.s.) Novo glucoamylase 150 L to reach a DE 96 in 22 h. Best total conversion was, however, obtained when also saccharification was initiated in the extruder by adding glucoamylase just before the die element, after lowering mass temperature to 60/sup 0/C, and by allowing the saccharification to continue at 60/sup 0/C after extrusion processing to reach a DE 94 in 5 h and DE 97 in 21 h.

  8. Microstructure, mechanical properties, biocorrosion behavior, and cytotoxicity of as-extruded Mg-Nd-Zn-Zr alloy with different extrusion ratios.

    Science.gov (United States)

    Zhang, Xiaobo; Yuan, Guangyin; Niu, Jialin; Fu, Penghuai; Ding, Wenjiang

    2012-05-01

    Recently, commercial magnesium (Mg) alloys containing Al (such as AZ31 and AZ91) or Y (such as WE43) have been studied extensively for biomedical applications. However, these Mg alloys were developed as structural materials, not as biomaterials. In this study, a patented Mg-Nd-Zn-Zr (denoted as JDBM) alloy was investigated as a biomedical material. The microstructure, mechanical properties, biocorrosion behavior, and cytotoxicity of the alloy extruded at 320 °C with extrusion ratios of 8 and 25 were studied. The results show that the lower extrusion ratio results in finer grains and higher strength, but lower elongation, while the higher extrusion ratio results in coarser grains and lower strength, but higher elongation. The biocorrosion behavior of the alloy was investigated by hydrogen evolution and mass loss tests in simulated body fluid (SBF). The results show that the alloy extruded with lower extrusion ratio exhibits better corrosion resistance. The corrosion mode of the alloy is uniform corrosion, which is favorable for biomedical applications. Aging treatment on the as-extruded alloy improves the strength and decreases the elongation at room temperature, and has a small positive influence on the corrosion resistance in SBF. The cytotoxicity test indicates that the as-extruded JDBM alloy meets the requirement of cell toxicity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. 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.

  10. Properties of extruded teff-oat composites

    Science.gov (United States)

    Teff is an ancient grain that is becoming more popular since it is gluten-free and a good source of vitamins, minerals and protein. Relatively little is known about the properties of extruded teff, although the high insoluble fiber and protein contents have been shown to limit expansion. The health ...

  11. Comparative study of the methane and methanol mass transfer in the mesoporous H-ZSM-5/alumina extruded pellet

    Science.gov (United States)

    Zhokh, Alexey A.; Strizhak, Peter E.

    2018-07-01

    H-ZSM-5/alumina catalyst pellet was prepared using extrusion method. The as-prepared mesoporous material was characterized using nitrogen adsorption, IR, XRD, and TEM methods. Transport of methane and methanol in the obtained H-ZSM-5/alumina extruded grain was studied. We demonstrate that the methanol transport may be described by the time-fractional diffusion equation in a fairly good manner. The measured value of the fractional order of the time-fractional derivative reveals the fast super-diffusive regime of the methanol transport in the mesoporous solid. Contrary, the methane transport has been found to follow a standard diffusion and described by the second Fick's law. These findings show that mass transfer kinetics is characterized by the order of the temporal derivative. The latter is a unique property of the individual porous media and the diffusing agent.

  12. Comparative study of the methane and methanol mass transfer in the mesoporous H-ZSM-5/alumina extruded pellet

    Science.gov (United States)

    Zhokh, Alexey A.; Strizhak, Peter E.

    2018-01-01

    H-ZSM-5/alumina catalyst pellet was prepared using extrusion method. The as-prepared mesoporous material was characterized using nitrogen adsorption, IR, XRD, and TEM methods. Transport of methane and methanol in the obtained H-ZSM-5/alumina extruded grain was studied. We demonstrate that the methanol transport may be described by the time-fractional diffusion equation in a fairly good manner. The measured value of the fractional order of the time-fractional derivative reveals the fast super-diffusive regime of the methanol transport in the mesoporous solid. Contrary, the methane transport has been found to follow a standard diffusion and described by the second Fick's law. These findings show that mass transfer kinetics is characterized by the order of the temporal derivative. The latter is a unique property of the individual porous media and the diffusing agent.

  13. 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.

  14. An in vitro comparison of apically extruded debris using three rotary nickel-titanium instruments

    Directory of Open Access Journals (Sweden)

    Tamer Tasdemir

    2010-09-01

    Conclusion: According to this study, all instrumentation techniques apically extruded debris through the apical foramen. However, the BioRaCe instruments induced less extruded debris than the ProTaper Universal and Mtwo rotary systems.

  15. 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.

  16. 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.

  17. 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.)

  18. A phenomenological study on twin screw extruders

    NARCIS (Netherlands)

    Janssen, L.P.B.M.

    1976-01-01

    Although more and more twin screw extruders are being used in the polymer industry, the theoretical background is relatively undeveloped. The literature abounds in contradictions and often informs the reader that all extrusion problems can be solved if a certain new design is considered. The

  19. Effect of heat treatments on the microstructure and mechanical properties of an extruded Mg{sub 95.5}Y{sub 3}Zn{sub 1.5} alloy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Huan; Xue, Feng, E-mail: xuefeng@seu.edu.cn; Bai, Jing; Sun, Yangshan

    2013-11-15

    The microstructure and mechanical properties of the extruded Mg{sub 95.5}Y{sub 3}Zn{sub 1.5} alloy under different heat treatment were systematically investigated by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and an electronic universal testing machine. The results show that the as-extruded alloy is composed of 18R LPSO stripes and α-Mg matrix with stacking faults (SFs) in it. The fine 14H LPSO lamellas are formed in α-Mg matrix near the areas of SFs during solution treatment at 500 °C for 8 h. A great number of fine β′ phases are precipitated in the α-Mg matrix of T6-treated (aging of the T4-treated alloy at 225 °C for 24 h) and T5-treated (aging of the as-extruded alloy at 225 °C for 32 h) alloys. Moreover, the SFs which were first observed in extruded alloy are retained in T5-staged specimen, and exhibit a cross arrangement with β′ precipitates. The absence of 14H LPSO phase in T5-treated alloy indicates that the 14H structure cannot be formed during aging at 225 °C. Tensile tests reveal that the presence of 14H lamellas improves the ductility of the alloy, but decreases the strength, suggesting that the 18R LPSO stripes are more effective in strengthening the alloy than 14H LPSO lamellas. The T6-staged alloy exhibits superior comprehensive mechanical properties with ultimate tensile strength of 358 MPa, tensile yield strength of 226 MPa and elongation of 6.1% at room temperature.

  20. Influence of whey protein concentrate addition on textural properties of corn flour extrudates

    Directory of Open Access Journals (Sweden)

    Mladen Brnčić

    2008-05-01

    Full Text Available Texture is an important propertiy of extruded snack products, and depended on extrusion process conditions, raw material properties and various ingredients properties as well. The main purpose of this research was, using twin-screw extrusion, to manufacture a direct expanded extrudate based on mixtures of corn flour and whey protein concentrate with acceptable textural properties. Mixtures were made of corn flour and three different concentrations of whey protein concentrate (7,5 %, 15 %, 22,5 %. Materials were processed in co-rotating twin-screw extruder APV Baker, MPF 50.15 under input conditions: water intake was 10,08 L/h, 12,18 L/h, 14,28 L/h, screw speed was 300 rpm; expansion temperature was 130 °C; feed rate was 70 kg/h. Textural properties: breaking strength index and expansion ratio were determined. Breaking strength index had largest value for the sample with 22,5 % of whey protein concentrate and water intake of 14,28 L/h. Sample with 7,5 % of whey protein concentrate and 10,08 L/h had largest expansion ratio. Calculated textural properties confirmed validity of samples. This results suggest that enrichment of extrudates with wpc addition up to 22,5 % to improve their nutritional value as well as their textural characteristics can be accomplished. Validation of direct expanded extrudates in dependence of its textural properties have shown validity and justification of this research.

  1. Development of protein, dietary fiber, and micronutrient enriched extruded corn snacks.

    Science.gov (United States)

    Shah, Faiz-Ul-Hassan; Sharif, Mian Kamran; Butt, Masood Sadiq; Shahid, Muhammad

    2017-06-01

    The study was aimed to develop protein, dietary fiber, and micronutrient enriched corn snacks through extrusion processing. Corn snacks supplemented with chickpea, defatted soy flour (20-40/100 g) and guar gum (7/100 g) were prepared through extrusion processing. Micronutrients (iron, zinc, iodine, and vitamins A, C, and folic acid) at recommended daily values were added in all formulations. Extruded corn snacks were analyzed for physical, textural, and sensory attributes. Results showed that piece density (0.34-0.44 g/cm 3 ), moisture (3.40-5.25%), water activity (0.203-0.361), hardness (64.4-133.2 N), and cohesiveness (0.25-0.44) was increased Whereas, expansion ratio (3.72-2.64), springiness (0.82-0.69), chewiness (1.63-0.42), and resilience (1.37-0.14) was decreased as supplementation with soy and chickpea flour increased from 20 to 40/100 g. Overall corn snack supplemented with 15/100 g of soy and 15/100 g of chickpea flour got the highest acceptance from the sensory panelists. The article focuses on physical, textural, and sensory attributes of extruded corn snacks enriched with protein, dietary fiber, and micronutrients Awareness about the importance of healthy snacks has grown among the consumers during the last decade. Extruded snacks developed using nutrient rich ingredients with good textural and sensory properties has always remained a challenge for the snack industry. Texture of the extruded snacks varies a lot with high levels of protein and dietary fiber. This study is helpful for the development of healthy snacks especially in developing countries lacking storage infrastructure or tropical environment. Nutrient rich extruded snacks can also be used to alleviate malnutrition by incorporating in school lunch programs. © 2016 Wiley Periodicals, Inc.

  2. Residence time distribution in twin-screw extruders

    NARCIS (Netherlands)

    Jager, T.

    1992-01-01

    For the twin-screw extruders used in the food industry at short time high temperature processes the knowledge of their reactor properties is incomplete for mass- and heat flow. Therefore each process change such as: scale-up or product development requires a great number of measurements

  3. Continuously graded extruded polymer composites for energetic applications fabricated using twin-screw extrusion processing technology

    Science.gov (United States)

    Gallant, Frederick M.

    A novel method of fabricating functionally graded extruded composite materials is proposed for propellant applications using the technology of continuous processing with a Twin-Screw Extruder. The method is applied to the manufacturing of grains for solid rocket motors in an end-burning configuration with an axial gradient in ammonium perchlorate volume fraction and relative coarse/fine particle size distributions. The fabrication of functionally graded extruded polymer composites with either inert or energetic ingredients has yet to be investigated. The lack of knowledge concerning the processing of these novel materials has necessitated that a number of research issues be addressed. Of primary concern is characterizing and modeling the relationship between the extruder screw geometry, transient processing conditions, and the gradient architecture that evolves in the extruder. Recent interpretations of the Residence Time Distributions (RTDs) and Residence Volume Distributions (RVDs) for polymer composites in the TSE are used to develop new process models for predicting gradient architectures in the direction of extrusion. An approach is developed for characterizing the sections of the extrudate using optical, mechanical, and compositional analysis to determine the gradient architectures. The effects of processing on the burning rate properties of extruded energetic polymer composites are characterized for homogeneous formulations over a range of compositions to determine realistic gradient architectures for solid rocket motor applications. The new process models and burning rate properties that have been characterized in this research effort will be the basis for an inverse design procedure that is capable of determining gradient architectures for grains in solid rocket motors that possess tailored burning rate distributions that conform to user-defined performance specifications.

  4. Extrudability and Consolidation of Blends between CGM and DDGS

    Directory of Open Access Journals (Sweden)

    C. J. R. Verbeek

    2016-01-01

    Full Text Available During the last decade, the global biofuels industry has experienced exponential growth. By-products such as high protein corn gluten meal (CGM and high fibre distillers dried grains with solubles (DDGS have grown in parallel. CGM has been shown to be suitable as a biopolymer; the high fibre content of DDGS reduces its effectiveness, although it is considerably cheaper. In this study, the processing behaviour of CGM and DDGS blends was evaluated and resulting extrudate properties were determined. Prior to processing, urea was used as a denaturant. DDGS : CGM ratios of 0, 33, 50, 66, and 100% were processed in a single screw extruder, which solely used dissipative heating. Blends containing DDGS were less uniformly consolidated and resulted in more dissipative heating. Blends showed multiple glass transitions, which is characteristic of mechanically compatible blends. Transmission electron microscopy revealed phase separation on a microscale, although distinct CGM or DDGS phases could not be identified. On a macroscale, optical microscopy suggested that CGM-rich blends were better consolidated, supported by visual observations of a more continuous extrudate formed during extrusion. Future work should aim to also characterize the mechanical properties of these blends to assess their suitability as either bioplastic feedstock or pelletized livestock feed.

  5. Study of Dynamic Flow and Mixing Performances of Tri-Screw Extruders with Finite Element Method

    OpenAIRE

    X. Z. Zhu; G. Wang; Y. D. He; Z. F. Cheng

    2013-01-01

    There is a special circumfluence in the center region of cross-section for a tri-screw extruder. To study the effect of the dynamic center region on the flow and mixing mechanism of the tri-screw extruder, 2D finite element modeling was used to reduce the axial effects. Based on the particle tracking technology, the nonlinear dynamics of a typical particle motions in the center region was carried out and the mixing process in the tri-screw extruder was analyzed with Poincaré maps. Moreover, m...

  6. Fortification of extruded snacks with chitosan: Effects on techno functional and sensory quality.

    Science.gov (United States)

    Kumar, Raushan; Xavier, K A Martin; Lekshmi, Manjusha; Balange, Amjad; Gudipati, Venkateshwarlu

    2018-08-15

    Chitosan is a dietary fibre that possesses numerous functional, technological and physiological properties useful in improving food quality. Owing to its fat absorbing ability, chitosan is widely consumed as a health supplement in the form of tablets and capsules. With a view to enhance it consumption and availability, the current work was taken up to evaluate techno-functional quality improvement of shrimp based extruded snacks fortified with chitosan. Chitosan powder at 1, 2 and 3% (w/w) level was added to the base material (corn flour and rice flour in the ratio of 70:30 and 15% Acetes powder) for extrusion. Addition of chitosan in acetes based snacks significantly reduced expansion ratio, porosity and crispiness and increased the hardness value of the product. Chitosan addition had a significant effect (p > 0.05) on the moisture retention and total protein contents of the products as well. Thiobarbituric acid reactive substances (TBARS) value of chitosan fortified extrudate showed a significantly lower value than the control sample. A higher level of chitosan also resulted in colour reduction of the final product. The FTIR spectra of extrudate confirmed the stability of chitosan during extrusion conditions. The sensory score revealed that extrudate fortified with 1% chitosan was comparable to control sample. From this study it is concluded that 1% chitosan can be incorporated in Acetes based extruded snacks for an increased level of functionality. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Successful reimplantation of extruded long bone segments in open fractures of lower limb--a report of 3 cases.

    Science.gov (United States)

    Shanmuganathan, Rajasekaran; Chandra Mohan, Arun Kamal; Agraharam, Devendra; Perumal, Ramesh; Jayaramaraju, Dheenadhayalan; Kulkarni, Sunil

    2015-07-01

    Extruded bone segments are rare complication of high energy open fractures. Routinely these fractures are treated by debridement followed by bone loss management in the form of either bone transport or free fibula transfer. There are very few reports in the literature about reimplantation of extruded segments of bone and there are no clear guidelines regarding timing of reimplantation, bone stabilisation and sterilisation techniques. Reimplantation of extruded bone is a risky procedure due to high chances of infection which determines the final outcome and can result in secondary amputations. We present two cases of successful reimplantation of extruded diaphyseal segment of femur and one case of reimplantation of extruded segment of tibia. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Physical evaluation of a maize-based extruded snack with curry powder.

    Science.gov (United States)

    Christofides, Vassilis; Ainsworth, Paul; Ibanoğlu, Senol; Gomes, Frances

    2004-02-01

    Response surface methodology was used to analyze the effect of screw speed (200-280 rpm), feed moisture (13.0-17.0%, wet basis), and curry powder (6.0-9.0%) on the bulk density, lateral expansion, and firmness of maize-based extruded snack with curry powder. Regression equations describing the effect of each variable on the responses were obtained. Responses were most affected by changes in feed moisture followed by screw speed and curry powder (p extruded product indicated by a higher correlation coefficient.

  9. Extruded black gram flour: Partial substitute for improving quality characteristics of Indian traditional snack

    Directory of Open Access Journals (Sweden)

    Laxmi Ananthanarayan

    2018-03-01

    Full Text Available Background: During extrusion of black gram flour, formation of amylose-lipid complexes lowers down the gelatinization enthalpy of extrudates, and the partially gelatinized black gram starch leads to lowering down the water-holding capacity and alters functional properties resulting in changing quality attributes of the end product on frying/microwaving/roasting. Methods: Attempts have been made to improve the quality of an Indian traditional snack (e.g., papad by incorporating extruded black gram flour as partial substitute for raw (unextruded black gram flour. In present work, overall quality improvement was achieved by analyzing prefrying and postfrying characteristics (diameter, moisture content, expansion ratio, oil uptake, texture, and color of papad and physical properties (color and viscosity of fried oil. Results: Four different papad samples were prepared (control papads without addition of papadkhar, papads with use of 3% papadkhar, papads with incorporation of extruded black gram flour at 25% concentration, papads with incorporation of extruded black gram flour at 50% concentration along with 1% papadkhar and analyzed along standard market sample. Incorporation of extruded black gram flour in papad resulted in greater expansion with less oil uptake in fried papad. Further addition of extruded black gram flour permitted the use of lower concentration of papadkhar. After frying, the quality of oil was characterized after numerous frying cycles. Conclusion: Oil used for frying of papads containing highest concentration of papadkhar was effective only up to two frying cycles, after which color and viscosity increased significantly, adversely affecting the quality of fried oil. Keywords: Black gram flour, Extrusion, Prefrying and postfrying characteristics of papad, Quality of fried oil

  10. Newly formulated, protein quality-enhanced, extruded sorghum-, cowpea-, corn-, soya-, sugar- and oil-containing fortified-blended foods lead to adequate vitamin A and iron outcomes and improved growth compared with non-extruded CSB+ in rats.

    Science.gov (United States)

    Delimont, Nicole M; Fiorentino, Nicole M; Opoku-Acheampong, Alexander B; Joseph, Michael V; Guo, Qingbin; Alavi, Sajid; Lindshield, Brian L

    2017-01-01

    Corn and soyabean micronutrient-fortified-blended foods (FBF) are commonly used for food aid. Sorghum and cowpeas have been suggested as alternative commodities because they are drought tolerant, can be grown in many localities, and are not genetically modified. Change in formulation of blends may improve protein quality, vitamin A and Fe availability of FBF. The primary objective of this study was to compare protein efficiency, Fe and vitamin A availability of newly formulated extruded sorghum-, cowpea-, soya- and corn-based FBF, along with a current, non-extruded United States Agency for International Development (USAID) corn and soya blend FBF (CSB+). A second objective was to compare protein efficiency of whey protein concentrate (WPC) and soya protein isolate (SPI) containing FBF to determine whether WPC inclusion improved outcomes. Eight groups of growing rats ( n 10) consumed two white and one red sorghum-cowpea (WSC1 + WPC, WSC2 + WPC, RSC + WPC), white sorghum-soya (WSS + WPC) and corn-soya (CSB14 + WPC) extruded WPC-containing FBF, an extruded white sorghum-cowpea with SPI (WSC1 + SPI), non-extruded CSB+, and American Institute of Nutrition (AIN)-93G, a weanling rat diet, for 4 weeks. There were no significant differences in protein efficiency, Fe or vitamin A outcomes between WPC FBF groups. The CSB+ group consumed significantly less food, gained significantly less weight, and had significantly lower energy efficiency, protein efficiency and length, compared with all other groups. Compared with WSC1 + WPC, the WSC1 + SPI FBF group had significantly lower energy efficiency, protein efficiency and weight gain. These results suggest that a variety of commodities can be used in the formulation of FBF, and that newly formulated extruded FBF are of better nutritional quality than non-extruded CSB+.

  11. Integration of β-glucan fibre rich fractions from barley and mushrooms to form healthy extruded snacks.

    Science.gov (United States)

    Brennan, Margaret A; Derbyshire, Emma; Tiwari, Brijesh K; Brennan, Charles S

    2013-03-01

    β-glucan is a commonly researched plant cell wall component that when incorporated into food products has been associated with cholesterol and glycaemic response reductions. This study focusses on β-glucan rich fractions from barley and mushroom used in the production of extruded ready to eat snacks. Inclusion of barley β-glucan rich fractions and mushroom β-glucan fractions at 10 % levels increased the total dietary fibre content of extrudates compared to the control (P extruded snack products.

  12. 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...

  13. Compositional profiling and sensorial analysis of multi-wholegrain extruded puffs as affected by fructan inclusion.

    Science.gov (United States)

    Handa, C; Goomer, S

    2015-09-01

    Rice grits, corn grits, pulse, wholegrain - finger millet and sorghum were utilized in the production of multigrain extruded puffs using a single screw extruder. The effect of inclusion of fructan - fructoligosaccharide in multi-wholegrain (MWG) extruded puffs was examined. MWG fructan enriched puffs puffs had 450 % higher dietary fiber content than the control puff (CP). These puffs can be categorized as 'Good Source' of fiber as it suffices 17.2 % DV of fiber. Puffs were rated 8.1 ± 0.6, 8.3 ± 0.7, 8.1 ± 0.6, 7.5 ± 0.5 and 8.2 ± 0.6 for color, flavor, texture, appearance and overall acceptability respectively. The scores for all the attributes were found to be not significantly different (p extruded puffs could be improved by the inclusion of fructans.

  14. Grain Refinement and Enhancement of Mechanical Properties of Hot Extruded Rare-Earth Containing Magnesium Alloy

    Directory of Open Access Journals (Sweden)

    Bita Pourbahari

    2017-12-01

    Full Text Available The effects of rare earth addition and hot extrusion process on the grain refinement of magnesium alloy were studied. The as-cast Mg-6Al-1Zn (AZ61 alloy had the average grain size of ~ 64 µm and its microstructure consisted of α-Mg and Mg17Al12 phase. By partial substitution of Al with Gd to reach Mg-4.8Gd-1.2Al-1Zn alloy, it was observed that the Mg17Al12 phase disappeared and two new intermetallic phases, i.e. (Mg,Al3Gd and Al2Gd, were identified. The extrusion process showed significant effects on the shape and size of intermetallics and grain size of the matrix. The grain size of the extruded Mg-6Al-1Zn alloy was refined from 64 µm to 13.4 µm as a result of recrystallization. Regarding the Mg-4.8Gd-1.2Al-1Zn alloy, the grain refinement was much more pronounced, where the extruded grain size has been refined from 698 µm to 2.4 µm (extruded at 385 °C and 1.3 µm (extruded at 320 °C. This was related to the presence of fine and widely dispersed intermetallic phases. Tensile strength and total elongation of extruded alloys were much higher than their as-cast counterparts and the extruded Mg-6Zn-1Al alloy showed magnificent mechanical properties. The latter was related to the absence of intermetallic particles, which act as stress risers.

  15. Method and apparatus for extruding thermoplastic material

    International Nuclear Information System (INIS)

    McKelvey, J.M.

    1985-01-01

    A gear pump assisted screw conveyor extrusion system utilizing a cartridge heating device disposed axially within the screw and having the drives for the gear pump and the screw correlated in speed to create relatively little pressure in the thermoplastic material being extruded such that relatively little mechanical working thereof occurs. The thermoplastic material is melted in the screw conveyor primarily by heat transfer from the cartridge heater and the gear pump is utilized for conveying the melted material under pressure to a subsequent work station. A relatively deep material-conveying spiral channel is provided in the screw for maximized extrusion output per revolution of the screw and minimized mechanical energy generation by the screw. A motionless mixer may be employed intermediate the screw and the work station to homogenize the melted material for reducing temperature gradients therein. The system advantageously is capable of extruding material at a substantially greater rate and a lower material temperature and with substantially increased power economy than conventional systems utilizing a high pressure, externally heated screw conveyor portion

  16. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Hot Deformation Behavior of Hot-Extruded AA7175 Through Hot Torsion Tests.

    Science.gov (United States)

    Lee, Se-Yeon; Jung, Taek-Kyun; Son, Hyeon-Woo; Kim, Sang-Wook; Son, Kwang-Tae; Choi, Ho-Joon; Oh, Sang-Ho; Lee, Ji-Woon; Hyun, Soong-Keun

    2018-03-01

    The hot deformation behavior of hot-extruded AA7175 was investigated with flow curves and processing maps through hot torsion tests. The flow curves and the deformed microstructures revealed that dynamic recrystallization (DRX) occurred in the hot-extruded AA7175 during hot working. The failure strain was highest at medium temperature. This was mainly influenced by the dynamic precipitation of fine rod-shaped MgZn2. The processing map determined the optimal deformation condition for the alloy during hot working.

  18. Characteristics of hydrostatically extruded Zr-2.5Nb alloy

    International Nuclear Information System (INIS)

    Jie, Z.; Jiaqi, D.; Tieqi, Y.; Wenxian, H.; Yan, L.; Yunxia, Z.; Zhenhe, L.

    1984-01-01

    Hydrostatic extrusion is a new production technology. Zr-2.5Nb alloy tubes cold hydrostatically extruded possess excellent mechanical properties similar to heat-treated tubes and better than cold-worked tubes. Examination by transmission electron microscope shows that the alloy is of a uniform cell substructure containing the (α + β) phases, which is one of important factors improving properties of the alloy. The study of texture, stress, and reorientation of the hydride shows that hydrostatically extruded tubes with basal plane normals in the radial direction have obviously higher hydride reorientation threshold stress than tubes with basal plane normals in the circumferential direction. Moreover, investigation of fracture toughness reveals that hydride distributed perpendicular to the crack propagation direction restrains further propagation of the crack. It is favorable for preserving the fracture resistance of the material

  19. An In vitro Comparison of Apically Extruded Debris Using Reciproc, ProTaper Universal, Neolix and Hyflex in Curved Canals

    Science.gov (United States)

    Labbaf, Hossein; Nazari Moghadam, Kiumars; Shahab, Shahriar; Mohammadi Bassir, Mahshid; Fahimi, Mohammad Amin

    2017-01-01

    Introduction: As a consequence of root canal preparation, dentinal chips, irrigants and pulp remnants are extruded into preradicular space. This phenomenon may lead to post endodontic flare-ups. The purpose of this study was to compare the amount of extruded debris with four endodontic NiTi engine-driven systems. Methods and Materials: Sixty mesiobuccal roots of maxillary molars with 15-30˚ curvature were divided randomly into four groups (n=15). Each group was instrumented up to apical size of 25 using Reciproc, ProTaper Universal, Neolix and Hyflex. Bidistilled water was used as irrigant and extruded debris was collected in pre-weighted Eppendorf tubes. Tubes were stored in incubator for drying the debris. Extruded debris were weighted in electronic microbalance with accuracy of 0.0001 g. The raw data was analyzed with one way analysis of variance (ANOVA) and Tukey’s HSD post hoc test. Level of significance was set at 0.05. Results: The debris extrusion with Reciproc files was significantly higher than the other groups (P<0.05). Hyflex significantly extruded less debris than other files (P<0.05). There was no significant difference between ProTaper Universal and Neolix regarding the amount of extruded debris (P=0.98). Conclusion: All systems extruded debris during the instrumentation. Reciproc system significantly extruded more debris. Caution should be taken when interpreting the results of this study and applying it to the real clinical situation. PMID:28808456

  20. Effects of forage type and extruded linseed supplementation on methane production and milk fatty acid composition of lactating dairy cows.

    Science.gov (United States)

    Livingstone, K M; Humphries, D J; Kirton, P; Kliem, K E; Givens, D I; Reynolds, C K

    2015-06-01

    Replacing dietary grass silage (GS) with maize silage (MS) and dietary fat supplements may reduce milk concentration of specific saturated fatty acids (SFA) and can reduce methane production by dairy cows. The present study investigated the effect of feeding an extruded linseed supplement on milk fatty acid (FA) composition and methane production of lactating dairy cows, and whether basal forage type, in diets formulated for similar neutral detergent fiber and starch, altered the response to the extruded linseed supplement. Four mid-lactation Holstein-Friesian cows were fed diets as total mixed rations, containing either high proportions of MS or GS, both with or without extruded linseed supplement, in a 4×4 Latin square design experiment with 28-d periods. Diets contained 500 g of forage/kg of dry matter (DM) containing MS and GS in proportions (DM basis) of either 75:25 or 25:75 for high MS or high GS diets, respectively. Extruded linseed supplement (275 g/kg ether extract, DM basis) was included in treatment diets at 50 g/kg of DM. Milk yields, DM intake, milk composition, and methane production were measured at the end of each experimental period when cows were housed in respiration chambers. Whereas DM intake was higher for the MS-based diet, forage type and extruded linseed had no significant effect on milk yield, milk fat, protein, or lactose concentration, methane production, or methane per kilogram of DM intake or milk yield. Total milk fat SFA concentrations were lower with MS compared with GS-based diets (65.4 vs. 68.4 g/100 g of FA, respectively) and with extruded linseed compared with no extruded linseed (65.2 vs. 68.6 g/100 g of FA, respectively), and these effects were additive. Concentrations of total trans FA were higher with MS compared with GS-based diets (7.0 vs. 5.4 g/100 g of FA, respectively) and when extruded linseed was fed (6.8 vs. 5. 6g/100 g of FA, respectively). Total n-3 FA were higher when extruded linseed was fed compared with no

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

    Science.gov (United States)

    Makowska, Agnieszka; Polcyn, Anna; Chudy, Sylwia; Michniewicz, Jan

    2015-01-01

    Cereal products constitute the basis of the diet pyramid. While the consumption of such products 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. 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. 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 desirability 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. In the production of corn extruded snacks an addition of oat, wheat and rye bran

  2. Carbonized tantalum catalysts for catalytic chemical vapor deposition of silicon films

    Energy Technology Data Exchange (ETDEWEB)

    Cheng Shimin [State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Dalian National Laboratory for Clean Energy, Dalian 116023 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Gao Huiping; Ren Tong; Ying Pinliang [State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Dalian National Laboratory for Clean Energy, Dalian 116023 (China); Li Can, E-mail: canli@dicp.ac.cn [State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Dalian National Laboratory for Clean Energy, Dalian 116023 (China)

    2012-06-01

    Catalytic chemical vapor deposition (Cat-CVD) has been demonstrated as a promising way to prepare device-quality silicon films. However, catalyst ageing due to Si contamination is an urgency to be solved for the practical application of the technique. In this study, the effect of carbonization of tantalum catalyst on its structure and performance was investigated. The carbonized Ta catalyst has a TaC surface layer which is preserved over the temperature range between 1450 and 1750 Degree-Sign C and no Si contamination occurs on the catalyst after long-term use. Si film prepared using the carbonized Ta catalyst has a similar crystal structure to that prepared by uncarbonized Ta catalyst. Formation of the TaC surface layer can alleviate the ageing problem of the catalyst, which shows great potential as a stable catalyst for Cat-CVD of Si films. - Highlights: Black-Right-Pointing-Pointer Si films prepared by catalytic chemical vapor deposition. Black-Right-Pointing-Pointer Carbonized Ta with a TaC surface layer used as catalyst. Black-Right-Pointing-Pointer TaC surface structure preserved after long-term use in a wide temperature range. Black-Right-Pointing-Pointer Help to solve the ageing problem of metal catalysts. Black-Right-Pointing-Pointer Si film obtained has a similar crystal structure to that prepared by Ta catalyst.

  3. The heat insulating properties of potato starch extruded with addition of chosen by- products of food industry

    Directory of Open Access Journals (Sweden)

    Zdybel Ewa

    2014-12-01

    Full Text Available The study was aimed at determination of time of heat transition through the layer of quince, apple, linen, rose pomace and potato pulp, as well as layer of potato starch and potato starch extruded with addition of above mentioned by-products. Additionally the attempt of creation a heat insulating barrier from researched raw material was made. The heat conductivity of researched materials was dependent on the type of material and its humidity. Extruded potato starch is characterized by smaller heat conductivity than potato starch extruded with addition of pomace. The obtained rigid extruded starch moulders were characterized by higher heat insulating properties than the loose beads. It is possible to use starch and by-products of food industry for production of heat insulating materials.

  4. 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...... dynamical parameters. This research sets the foundation for further research within melted extrusion based additive manufacturing. The heating process of the extruder will be described and a note on the material feeding will be given....

  5. 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.

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

    Directory of Open Access Journals (Sweden)

    Mohd Hafizuddin Ab Ghani

    2011-01-01

    Full Text Available 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 corotating twin screw, respectively. The contents of matrix (30 wt% and fibres (62 wt% were mixed with additives (8 wt% and compounded using compounder before extruded using both of the machines. Samples were immersed in distilled water according to ASTM D 570-98. From the study, results indicated a significant difference among samples extruded by counterrotating and corotating twin-screw extruders. The counterrotating twin-screw extruder gives the smallest value of water absorption compared to corotating twin-screw extruder. This indicates that the types of screw play an important role in water uptake by improving the adhesion between natural fillers and the polymer matrix.

  7. Evaluation of the amount of apically extruded debris during ...

    African Journals Online (AJOL)

    2015-04-06

    Apr 6, 2015 ... Objective: To evaluate the amount of apically extruded debris during retreatment (with or without solvent) of root canals filled by two ... These filling materials can be used with several obturation .... The tip of the master cone.

  8. Performance of calves submitted to protocols using extruded or ground starter

    Directory of Open Access Journals (Sweden)

    Amália Saturnino Chaves

    2014-10-01

    Full Text Available Feed processing can affect rumen development in new born calves, and potentially define animal performance. Two feed management systems, extruded starter (Ruter with possible early weaning and ground starter (control, were evaluated in thirty-two Holstein calves (16 females and 16 males. Animals were randomly assigned to the treatments using a randomized block design with birth weight as a covariate. They were weaned when starter intake reached 800 g for two consecutive days. Twenty-one days after the weaning, males were slaughtered and the stomach compartments were isolated. Rumen and omasum fragments were processed for morphological evaluation. Animal performance, clinical condition and stomach compartment weight did not differ between the treatments (P> 0.05, despite weaning weight of animals receiving extruded starter being 5.68% higher than the control animals. Extruded starter stimulated cell proliferation of the ruminal epithelium (P <0.05, but did not affect the dimensions of the papillary rumen and omasum mitotic index (MI. The Ruter feeding system was potentially beneficial for weight gain and morphofunctional rumen development in lactating animals; however, this treatment did not allow early weaning as proposed by the feeding system.

  9. Effect of composition and processing conditions on selected characteristics of extruded corn instant gruels enriched with fruits addition

    Directory of Open Access Journals (Sweden)

    Kręcisz Magdalena

    2018-01-01

    Full Text Available Cranberries and goji berries were used as natural supplements in extruded instant corn gruels. The effects of additive type and level, as well as extrusion-cooking screw speed on selected properties of extrudates were tested. Corn grit was used as the base raw materials and dry and ground goji berries and cranberries were added at 1, 2, 3, 4 and 5%. Extrusion-cooking of blends was performed with a single screw extruder at temperature ranged 125-135°C using various screw speed during processing. Extrudates were ground below 1 mm for instant gruels. Water absorption, water solubility, as well as colour profile were tested. The results showed that the highest water absorption was evaluated for instant gruels consist the highest amount of goji berries extruded at the highest screw speed during processing, while cranberries addition have no significant effect on water absorption. Increasing amount of dry cranberries and goji berries in the recipe affected on lowering the water solubility of the extrudates. Significant effect of fruits on color coordinates was observed. Increasing amount of dry berries lowered lightness L* and yellowness of instant gruels, especially when goji berries were used in the recipe. Increasing the screw speed during processing decreased intensity b* values.

  10. Comparison of waste pumpkin material and its potential use in extruded snack foods.

    Science.gov (United States)

    Norfezah, M N; Hardacre, A; Brennan, C S

    2011-08-01

    Material was produced from Crown pumpkin (Cucurbita maxima) processed from fractions of the fruit which are regarded as waste stream products (peel, flesh and seed). The flour from the three different fractions (peel, flesh and seed) of Crown pumpkin flour was incorporated into an extruded snack product formulation at levels 10%, 30% and 50% (w/w with corn grit) and processed in a twin-screw extruder to make 10 expanded snack products. Proximate analysis was carried out to determine the nutritional value of the raw pumpkin and pumpkin flour. A physical analysis of the product was used to determine its color, the expansion ratio, bulk density and texture. Inclusion of waste stream material (peel and seed) at 10%, yielded extruded products with similar expansion and density characteristics to the control sample; however, an inclusion of greater than 10% yielded significant challenges to product quality (hardness of the product).

  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. The effect of moisture content on physicochemical properties of extruded waxy and non-waxy rice flour.

    Science.gov (United States)

    Jongsutjarittam, Ornpicha; Charoenrein, Sanguansri

    2014-12-19

    The properties of waxy rice flour (WRF) and non-waxy rice flour (RF) were modified using an extrusion process with different feeding material moisture contents. WRF was more affected by the thermomechanical stress from extrusion; consequently, it had a lower glass transition temperature but higher water solubility index (WSI) indicating higher molecular degradation than extruded RF. The lower moisture content of the feeding flour caused more severe flour damage (coarser surface of the extruded flour) and lowered relative crystallinity compared to higher moisture content processing. Moreover, low moisture content processing led to complete gelatinization, whereas, partial gelatinization occurred in the higher moisture content extrusion. Consequently, the extruded flours had a lower peak viscosity and gelatinization enthalpy but a higher water absorption index and WSI than native flour. In conclusion, the rice flour type and the moisture content of the extrusion feeding flour affected the physicochemical properties of the extruded flour. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. 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.

  14. Chemistry and heat-treatment effects on mechanical and microstructural properties of heat-treated, beta-extruded Ti--6A1--6V--2Sn

    International Nuclear Information System (INIS)

    Ulitchny, M.G.; Rack, H.J.; Dawson, D.B.

    1979-04-01

    The mechanical behavior of beta-extruded Ti--6A1--6V--2Sn was examined after a variety of sub-transus heat treatments. The microstructural variations resulting from the range of heat treatments studied also were examined. A range of alloy chemistries, within commercial limits, was used to evaluate the effect of this variable on mechanical properties. The strength--toughness combinations obtained in beta-extruded Ti--6A1--6V--2Sn ranged from about 895 MPa and 82.5 MPa√m for duplex annealed material to 1200 MPa and 54.9 MPa√m for solution treated and peak aged material. Chemistry variations had less effect on mechanical properties than would have been the case with alpha--beta processing

  15. Effects of selected process parameters in extrusion of yam flour (Dioscorea rotundata) on physicochemical properties of the extrudates.

    Science.gov (United States)

    Sebio, L; Chang, Y K

    2000-04-01

    Raw yam (Dioscorea rotundata) flour was cooked and extruded in a Brabender single-screw laboratory scale extruder. Response surface methodology using an incomplete factorial design was applied with various combinations of barrel temperature [100, 125, 150 degrees C], feed moisture content [18, 22, 26%] and screw speed [100, 150, 200 rpm]. Initial viscosity at 30 degrees C, water solubility index, expansion and hardness were determined. The highest values of initial viscosity were at the highest barrel temperatures and the highest moisture contents. At high feed moisture content and high barrel temperatures the yam extrudate flour showed the greatest values of water solubility index. The physical properties of the extruded product showed that at high temperature the lower the moisture content the greater the expansion index. Hardness was influenced directly by moisture content and inversely by extrusion temperature. The extrusion of yam flour led to the production of snacks and pre-gelatinized flours of diverse properties. Also extruded yam flour can be successfully used in the preparation of 'futu' (pre-cooked compact dough), a yam-based food, popular in Western Africa.

  16. Comparison of Extruder Systems for 3D Printer Filament Fabrication

    Science.gov (United States)

    Ramirez, Adriana

    Additive Manufacturing (AM) has grown in popularity over the past thirty years, due to its versatility, short design to product cycle, and capability to fabricate complex geometries, which cannot otherwise be produced. There exist several platforms that are able to print objects composed of different materials, making this technology significant in different fields such as: automotive, aerospace, medical, electronics, amongst others. Though several types of AM technologies are available, the expiration of the patents on fused deposition modeling (FDM) in 2009 has led to a widespread use of this platform in academia and home use settings. Widespread use of FDM-type AM platforms has led to a demand to fabricate feedstock materials for this AM platform. Particularly, in the home do it yourself (DIY) community there has been a widespread interest for users to manufacture their own feedstock filament leading to a large growth in home-use extrusion systems. The low cost of these desktop-grade systems has also made them attractive to academics, but there has not been a widespread effort into determining the efficacy of these small scale extrusion systems as compared to industrial quality extruders which are typically used to manufacture feedstock for FDM platforms. The aim of this study was to compare two extrusion processes: 1) a desktop grade single-screw extruder; and 2) an industrial scale twin-screw extruder. In order to understand differences between their performance and quality of mixing, a rubberized blend of acrylonitrile butadiene styrene (ABS) mixed with styrene ethylene butylene styrene with a maleic anhydride graft (SEBS-g-MA) at different ratios was compounded on each extrusion system. Melt flow index, and mechanical properties were compared. In addition, a raster pattern sensitivity study was performed to evaluate the effect of the extruder system on 3D printed objects. Finally, scanning electron microscopy (SEM) was used to examine the fracture surfaces

  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.

  18. Influence of Extrusion Temperature on the Aging Behavior and Mechanical Properties of an AA6060 Aluminum Alloy

    Directory of Open Access Journals (Sweden)

    Nadja Berndt

    2018-01-01

    Full Text Available Processing of AA6060 aluminum alloys for semi-products usually includes hot extrusion with subsequent artificial aging for several hours. Processing below the recrystallization temperature allows for an increased strength at a significantly reduced annealing time by combining strain hardening and precipitation hardening. In this study, we investigate the potential of cold and warm extrusion as alternative processing routes for high strength aluminum semi-products. Cast billets of the age hardening aluminum alloy AA6060 were solution annealed and then extruded at room temperature, 120 or 170 °C, followed by an aging treatment. Electron microscopy and mechanical testing were performed on the as-extruded as well as the annealed materials to characterize the resulting microstructural features and mechanical properties. All of the extruded profiles exhibit similar, strongly graded microstructures. The strain gradients and the varying extrusion temperatures lead to different stages of dynamic precipitation in the as-extruded materials, which significantly alter the subsequent aging behavior and mechanical properties. The experimental results demonstrate that extrusion below recrystallization temperature allows for high strength at a massively reduced aging time due to dynamic precipitation and/or accelerated precipitation kinetics. The highest strength and ductility were achieved by extrusion at 120 °C and subsequent short-time aging.

  19. 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.

  20. Theoretical and Experimental Study of Thermoacoustic Engines

    Science.gov (United States)

    1991-12-31

    possible. In particulbr, we have considered use of extruded ceramic monolithic catalyst supports (for example, the ceramic used in some automobile...approximation. Heat exchangers retaken r be of negligible thickness and thus not to affect near-standing wave phasing. The TAB (or snack ) of length d is assumed...Heat exchangers were parallel plates of copper and the TAE is a monolithic catalyst support extruded ceramic. 13 15 The two-microphone-technique

  1. 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.

  2. 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.

  3. Fabrication and properties of high-strength extruded brass using elemental mixture of Cu-40% Zn alloy powder and Mg particle

    Energy Technology Data Exchange (ETDEWEB)

    Atsumi, Haruhiko, E-mail: atsumi-h@jwri.osaka-u.ac.jp [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Imai, Hisashi; Li, Shufeng; Kondoh, Katsuyoshi [Joining and Welding Research Institute, Osaka University, 11-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Kousaka, Yoshiharu; Kojima, Akimichi [San-etsu Metals Co. Ltd., 1892 Ohta, Tonami, Toyama 939-1315 (Japan)

    2012-08-15

    In this paper, high-strength brass (Cu-40% Zn) alloy with magnesium (Mg) element was fabricated via powder technology process, and the effect of the additive Mg element on microstructural and mechanical properties of extruded brass alloys with {alpha}-{beta} duplex phases was investigated. Pre-mixed Cu-40% Zn alloy powder with 0.5-1.5 mass% pure Mg powder (Cu-40% Zn + Mg) was consolidated using a spark plasma sintering (SPS) equipment. SPSed Cu-40% Zn + Mg specimens consisted of {alpha}-{beta} duplex phases containing Mg(Cu{sub 1-x}Zn{sub x}){sub 2} intermetallic compounds (IMCs) with a mean particle size of 10-30 {mu}m in diameter. The IMCs were completely dissolved in the {alpha}-{beta} duplex phases by a heat-treatment at 973 K for 15 min; thus, in order to disperse fine IMCs on {alpha}-{beta} duplex phase matrix, the SPSed Cu-40% Zn + Mg specimens were pre-heated at the solid solutionizing condition, and immediately extruded. The extruded specimen exhibited fine {alpha}-{beta} duplex phases, containing very fine precipitates of the above Mg(Cu{sub 1-x}Zn{sub x}){sub 2} IMCs with 0.5-3.0 {mu}m in diameter. In particular, a mean grain size of the extruded Cu-40% Zn + 1.0% Mg specimen was 3.32 {mu}m analyzed using an electron back-scattered diffraction. Tensile properties of the extruded Cu-40% Zn + 1.0% Mg specimen were an average value of yield strength (YS): 328 MPa, ultimate tensile strength (UTS): 553 MPa, and 25% elongation. This indicated that the extruded Cu-40% Zn + 1.0% Mg specimen revealed the significantly high-strength properties compared to a conventional binary brass alloy with 229 MPa YS and 464 MPa UTS. A high strengthening mechanism of this wrought brass alloy was mainly due to the grain refinement because of a pinning effect by the fine Mg(Cu{sub 1-x}Zn{sub x}){sub 2} precipitates at the boundaries of each phase. -- Highlights: Black-Right-Pointing-Pointer New high-strength extruded brass alloy with Mg was fabricated via powder metallurgy. Black

  4. Development of extruded Ready-To-Eat (RTE) snacks using corn, black gram, roots and tuber flour blends.

    Science.gov (United States)

    Reddy, M Kavya; Kuna, Aparna; Devi, N Lakshmi; Krishnaiah, N; Kaur, Charanjit; Nagamalleswari, Y

    2014-09-01

    Extruded RTE snacks were prepared from flour blends made with corn flour, Bengal gram flour, roots and tuber flours in a proportion of 60-80: 20: 20 respectively and moisture was adjusted to 17-20 %. The roots and tubers flours were developed from potato (Solanum tuberosum), yam (Dioscorea spp.), sweet potato (Ipomoea batatas L.), taro (Colocassia esculenta) and beet root (Beta vulgaris). Different formulations were extruded at 80 ± 5 °C (heater I) and 95-105 °C (heater II) temperature, 300-350 rpm screw speed, 100 ± 10 °C die temperature and 15 ± 2 kg/h feed rate. The exit diameter of the circular die was 3 mm. Sensory acceptability, physical parameters and nutrient analysis along with storage stability of the products was conducted. The fiber and energy content of the RTE extruded snack improved in experimental samples prepared using root and tuber flours. A serving of 100 g of the snack can provide more than 400 Kcal and 10 g of protein. The overall acceptability of RTE extruded products made with potato and taro were highly acceptable compared to yam and sweet potato. The study demonstrates utilization of roots and tuber flours as potential and diverse ingredients to enhance the appearance and nutritional properties in RTE extruded snack.

  5. The synergistic effect of Li addition on microstructure, texture and mechanical properties of extruded Al–Mg–Si alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ud Din, Shamas; Kamran, J. [Department of Metallurgy and Materials Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamabad, 45650 (Pakistan); Tariq, N.H., E-mail: naeem421@hotmail.com [Department of Metallurgy and Materials Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamabad, 45650 (Pakistan); Hasan, B.A. [Department of Metallurgy and Materials Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamabad, 45650 (Pakistan); Petrov, R.H.; Bliznuk, V. [Ghent University, Department of Materials Science and Engineering, Technologiepark 903, Gent (Belgium); Uz Zuha, Shamas [Department of Metallurgy and Materials Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), Nilore, Islamabad, 45650 (Pakistan)

    2016-05-01

    In the present work, 0, 1, 2 and 3 wt.% Li was added to conventional Al-0.9Mg-0.5Si alloy. The samples were extruded and aged to investigate the effect of Li addition on microstructure, texture and mechanical properties. The density of conventional alloy was reduced up to 7.8% while the ultimate tensile strength (UTS) increased by 62% with 3% Li addition. Electron backscatter diffraction (EBSD) revealed that Li addition effectively refined the grain size of the modified alloys. TEM/EDX and XRD analysis revealed the synergistic effect of Li addition which promoted the formation of nano-sized δ′(Al{sub 3}Li) precipitates when Li content is higher then 1%. The ageing trend first decreased for 1 wt.% Li addition and then increased with increasing Li content from 2 to 3 wt.% at the expense of ductility. The intensity of texture increased with the gradual increase in Li content from alloy-1 to 4. - Highlights: • Study of 0, 1, 2 and 3 wt.% Li on Al–Mg–Si alloys in extruded and T6 condition. • Density reduced to 7.8% with UTS increased by 62% for 3% Li addition. • Texture intensity increased with increase in Li content from alloy-1 to 4. • Property enhancement attributed to a refinement of δ′ (Al{sub 3}Li) precipitates.

  6. Dissolved oxygen removal in a column packed with catalyst

    International Nuclear Information System (INIS)

    Lee, Han Soo; Chung, Hong Suk; Cho, Young Hyun; Ahn, Do Hee; Kim, Eun Kee

    1996-01-01

    The dissolved oxygen removed by H 2 -O 2 reaction in column packed with various catalysts was examined. The catalysts employed were the prepared polymeric catalyst, platinum on activated carbon, and Lewatit OC-1045 which is available commercially. The column experiments with the prepared polymeric catalyst showed the dissolved oxygen reduced to 35 ppb which is below the limit in feel water of power plants. This implies the likely application of the prepared catalyst for practical use. The activated carbon required the pre-treatment for the removed of dissolved oxygen, since the surface of activated carbon contains much oxygen adsorbed initially. The Lewatit catalyst exposed the best performance, however, the aged one showed the gradual loss of catalytic activity due to degradation of resin catalyst. 14 refs., 6 figs., 2 tabs. (author)

  7. Deformation structure of water atomised and extruded Cu-Cr-Zr alloys

    International Nuclear Information System (INIS)

    Correia, J.B.; Davies, H.A.; Sellars, C.M.

    1994-01-01

    Copper alloy powders containing Cr and/or Zr were produced via water atomisation and consolidated by extrusion. The crystallographic orientations relative to the extrusion axis, both in the as-extruded condition and after heat treatment were assessed by an inverse pole figure texture determination method using X-ray diffraction. Transmission electron microscopy (TEM) was also used for microstructural observations. The as-extruded materials showed a clear double fibre texture ( left angle 111 right angle + left angle 100 right angle ), the left angle 111 right angle component being the stronger. After isochronal 1 hour heat treatments in the temperature range 400-700 C, a clear trend of a decreasing left angle 111 right angle component with increasing temperatures was seen. For the highest heat treatment temperature used (700 C), the alloys approached a random crystallographic distribution. The microstructure of the as-extruded material showed a banded structure with sharp boundaries parallel to the extrusion direction. Also, the left angle 111 right angle or left angle 100 right angle directions were generally parallel to the extrusion direction. TEM observation of longitudinal sections after exposure to increasingly high temperature, notably above 500 C, indicated that boundaries started to lose their sharpness and to spread sideways. When the same materials were observed in transverse sections, the competitive growth of some subgrains was clearly seen. (orig.)

  8. 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. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Modeling The Effect Of Extruder Screw Speed On The Mechanical ...

    African Journals Online (AJOL)

    Modeling The Effect Of Extruder Screw Speed On The Mechanical Properties Of High Density Polyethylene Blown Film. ... Journal of Modeling, Design and Management of Engineering Systems ... Two sets of multiple linear regression models were developed to predict impact failure weight and tenacity respectively.

  10. Parameters Affecting the Extraction Process of Jatropha Curcas Oil Using a Single Screw Extruder

    OpenAIRE

    Siregar, Ali Nurrakhmad; Ghani, Jaharah A; Che Haron, Che Hassan; Rizal, Muhammad

    2015-01-01

    The most commonly used technique to separate oil and cake from J. curcas seeds is mechanical extraction. It uses simple tools such as a piston and a screw extruder to produce high pressure, driven by hand or by engine. A single screw extruder has one screw rotating inside the barrel and materials simultaneously flow from the feed to the die zone. The highest oil yield can be obtained by a well-designed oil press as well as finding the optimum conditions for all parameters involved during the ...

  11. Preparation and Evaluation of Hot-Melt Extruded Patient-Centric Ketoprofen Mini-Tablets.

    Science.gov (United States)

    Alshetaili, Abdullah S; Almutairy, Bjad K; Tiwari, Roshan V; Morott, Joseph T; Alshehri, Sultan M; Feng, Xin; Alsulays, Bader B; Park, Jun-Bom; Zhang, Feng; Repka, Michael A

    2016-01-01

    Bitter tasting drugs represent a large portion of active pharmaceutical ingredients. Mini-tablets are specifically designed for patients with difficulty in swallowing particular in young children up to 10 years of age, geriatric patients and patients with esophagitis. The present study was aimed to prepare, taste-masked mini-tablets, which are easily swallowed dosage forms, primarily to be used by pediatric and geriatric patients. Ketoprofen (10%-50% w/w) and Eudragit® EPO were blended and extruded with a 5-mm strand die and cut into consistent mini-tablets by using an adapted downstream pelletizer. Differential scanning calorimetry and polarized light microscopy-hot stage microscopy studies confirmed that the binary mixtures were miscible under the employed extrusion temperatures. In-vitro release studies showed that drug release was less than 0.5% within the first 2 min in simulated salivary fluid (pH 6.8) and more than 90% in the first 20 min in gastric media (pH 1.0). The results of the electronic tongue analysis were well correlated with the drug release profile of the mini-tablets in the artificial saliva. Scanning electron microscopy revealed no cracks on the surface of the minitablets, confirming that the mini-tablets were compact solids. Chemical imaging confirmed the uniform distribution of ketoprofen inside the polymer matrices. Eudragit® EPO containing ketoprofen at various drug loads were successfully melt extruded into tastedmasked mini-tablets. The reduced drug release at salivary pH correlated well with Astree e-Tongue studies for taste masking efficiency.

  12. Influence of dried Hokkaido pumpkin and ascorbic acid addition on chemical properties and colour of corn extrudates.

    Science.gov (United States)

    Obradović, Valentina; Babić, Jurislav; Šubarić, Drago; Jozinović, Antun; Ačkar, Đurđica; Klarić, Ilija

    2015-09-15

    The influence of Hokkaido pumpkin powder (PP) addition to corn grits at levels 4%, 6%, and 8% and ascorbic acid (AA) addition at levels 0.5% and 1% was evaluated. Extrusion was done using a single-screw extruder at two temperature regimes: 135/170/170°C (E1) and 100/150/150°C (E2). Mathematical models that describe the influence of additives on the colour of extrudates were determined. Raw extrusion mixtures as well as obtained extrudates were tested for ascorbic acid, polyphenol, proteins, fat, crude fibre, ash and carotenoids content, and antioxidant activity. E1 extrusion regime acted favourably on polyphenols, crude fibre content, and antioxidant activity. It also caused higher fat degradation than E2 extrusion. Xanthophylls (lutein and zeaxanthin) were less sensitive to extrusion than carotenes (α-carotene, 9-cis-β-carotene and 13-cis-β-carotene). Ascorbic acid was more sensitive to higher extrusion temperatures (49-76% degradation). It provided protection to carotenoids and consequently the colour of the extrudates. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Oxidation catalyst

    Science.gov (United States)

    Ceyer, Sylvia T.; Lahr, David L.

    2010-11-09

    The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

  14. Influence of lidocaine forms (salt vs. freebase) on properties of drug-Eudragit® L100-55 extrudates prepared by reactive melt extrusion.

    Science.gov (United States)

    Liu, Xu; Ma, Xiangyu; Kun, Eucharist; Guo, Xiaodi; Yu, Zhongxue; Zhang, Feng

    2018-06-05

    This study examines the preparation of sustained-release lidocaine polyelectrolyte complex using reactive melt extrusion. Eudragit L100-55 was selected as the ionic polymer. The influence of drug forms (freebase vs. hydrochloride salt) on lidocaine-Eudragit L100-55 interactions, physical stability, and dissolution properties of extrudates was investigated. It was confirmed by DSC, FT-IR and Raman spectroscopy that polyelectrolyte could only form via the acid-base reaction between Eudragit L100-55 and lidocaine freebase. Due to this ionic interaction, the lidocaine extrudate was physically more stable than the lidocaine hydrochloride extrudate during the storage under stressed condition. Drug release from lidocaine extrudate was a function of drug solubility, polymer solubility, drug-polymer interaction, and drug-induced microenvironment pH. At 30% drug loading, extrudate exhibited sustained release in aqueous media at pH 1.2 and 4.5. Due to the alkaline microenvironment pH induced by dissolved lidocaine, Eudragit L100-55 was solubilized and sustained-release was not achieved in water and aqueous media at pH 5.5. In comparison, lidocaine hydrochloride induced an acidic microenvironment. Drug release of lidocaine hydrochloride extrudate was similar at pH 1.2, 4.5, 5.5 and water with drug being released over 10 hours. The release of lidocaine hydrochloride from the extrudates in these media was primarily controlled by microenvironment pH. It is concluded that different forms of lidocaine resulted in different drug-polymer interactions and distinctive physicochemical properties of extrudates. Copyright © 2018. Published by Elsevier B.V.

  15. 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.

  16. Alfalfa silage ratios and full fat extruded soybeans on milk

    African Journals Online (AJOL)

    USER

    2010-08-16

    Aug 16, 2010 ... Treatments were arranged in a 2 × 3 factorial with 0 or 5% full fat extruded soybeans meal (dry matter basis) and ... Milk fat and lactose were not affected by replacing corn .... The oven temperature was initially 180°C for 45.

  17. Investigation of heat transfer for extruded polymers cooled in water

    CSIR Research Space (South Africa)

    Kumar, R

    2015-10-01

    Full Text Available . The temperature of still water after 1, 5 and 10 min were determined experimentally using the digital temperature sensor. The temperature gains for the water after the immersion of the extruded polymers were determined at different time intervals. In the second...

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

    International Nuclear Information System (INIS)

    Sim, Su Youn; Park, Ji Seon; Ryu, Kyung Nam; Jin, Wook

    2007-01-01

    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 (ρ 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 (ρ = 0.125). It is necessary to consider the possibility of the presence of a sequestered disc when a herniated disc material shows a notch

  19. 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.

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

    Science.gov (United States)

    Anjum, Faqir Muhammad; Haider, Muhammad Faizan; Khan, Muhammad Issa; Sohaib, Muhammad; Arshad, Muhammad Sajid

    2013-02-08

    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.

  1. 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.

  2. [Extruded rice flour as a gluten substitute in the poduction of rice bread].

    Science.gov (United States)

    Clerici, Maria Teresa Pedrosa Silva; El-Dash, Ahmed A

    2006-09-01

    Research regarding the production of gluten-free bread (GFB) is very important nutritionally, technically and economically speaking, both to celiac patients and to developing countries who import wheat. The main technological problem in the production of GFB is obtaining a gluten substitute that is both inexpensive and capable of retaining gas during bread fermentation and baking. The use of gelatinized starch as an alternative for gluten seems promising. In this project, rice bread was made using pregelatinized extruded rice flour as a gluten substitute. Pre-gelatinized rice flours (PRF) were manufactured in a single screw Brabender extruder, varying extrusion temperature (108-192 degrees C) and the moisture of the raw material (19.2 - 24.8%), and were used in a proportion of 10 g for every 100 g of raw rice flour, in the production of gluten-free bread. Results showed that rice flour extruded at a high temperature (180 degrees) and low moisture content (20%), rendered bread with the best technological characteristics, presenting crust and crumb color similar to those of conventional wheat bread, although with volume and texture not as satisfactory in the same comparison.

  3. Effect of Some Extrusion Variables on Rheological Properties and Physicochemical Changes of Cornmeal Extruded by Twin Screw Extruder

    OpenAIRE

    Chang Y.K.; Martínez-Bustos f.; Lara h.

    1998-01-01

    The effect of extrusion variables, such as barrel temperature (100 to 170ºC), feed rate (100 to 500 g/min), feed moisture (20 to 40 g/100 g wet basis), screw speed rate (from 100 to 500 rpm), and slit die rheometer configuration (0.15 and 0.30 cm height) were studied using a co-rotating intermeshing twin-screw extruder coupled to a slit die rheometer on the rheological properties of yellow cornmeal. An increase in feed rate decreased WAI and WSI, but increased the viscosity values. The temper...

  4. 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.

  5. Iron Bioavailability from Ferric Pyrophosphate in Extruded Rice Cofortified with Zinc Sulfate Is Greater than When Cofortified with Zinc Oxide in a Human Stable Isotope Study.

    Science.gov (United States)

    Hackl, Laura; Zimmermann, Michael B; Zeder, Christophe; Parker, Megan; Johns, Paul W; Hurrell, Richard F; Moretti, Diego

    2017-03-01

    Background: Extruded rice grains are often cofortified with iron and zinc. However, it is uncertain if the addition of zinc to iron-fortified rice affects iron absorption and whether this is zinc-compound specific. Objective: We investigated whether zinc, added as zinc oxide (ZnO) or zinc sulfate (ZnSO 4 ), affects human iron absorption from extruded rice fortified with ferric pyrophosphate (FePP). Methods: In 19 iron-depleted Swiss women (plasma ferritin ≤16.5 μ/L) aged between 20 and 39 y with a normal body mass index (in kg/m 2 ; 18.7-24.8), we compared iron absorption from 4 meals containing fortified extruded rice with 4 mg Fe and 3 mg Zn. Three of the meals contained extruded rice labeled with FePP ( 57 FePP): 1 ) 1 meal without added zinc ( 57 FePP-Zn), 2 ) 1 cofortified with ZnO ( 57 FePP+ZnO), and 3 ) 1 cofortified with ZnSO 4 ( 57 FePP+ZnSO 4 ). The fourth meal contained extruded rice without iron or zinc, extrinsically labeled with ferrous sulfate ( 58 FeSO 4 ) added as a solution after cooking. All 4 meals contained citric acid. Iron bioavailability was measured by isotopic iron ratios in red blood cells. We also measured relative in vitro iron solubility from 57 FePP-Zn, 57 FePP+ZnO, and 57 FePP+ZnSO 4 expressed as a fraction of FeSO 4 solubility. Results: Geometric mean fractional iron absorption (95% CI) from 57 FePP+ZnSO 4 was 4.5% (3.4%, 5.8%) and differed from 57 FePP+ZnO (2.7%; 1.8%, 4.1%) ( P iron bioavailabilities compared with 58 FeSO 4 were 62%, 57%, and 38% from 57 FePP+ZnSO 4 , 57 FePP-Zn, and 57 FePP+ZnO, respectively. In vitro solubility from 57 FePP+ZnSO 4 differed from that of 57 FePP-Zn (14.3%; P iron-depleted women, iron absorption from FePP-fortified extruded rice cofortified with ZnSO 4 was 1.6-fold (95% CI: 1.4-, 1.9-fold) that of rice cofortified with ZnO. These findings suggest that ZnSO 4 may be the preferable zinc cofortificant for optimal iron bioavailability of iron-fortified extruded rice. This trial was registered at

  6. Assessment of apically extruded debris produced by the single-file ProTaper F2 technique under reciprocating movement.

    Science.gov (United States)

    De-Deus, Gustavo; Brandão, Maria Claudia; Barino, Bianca; Di Giorgi, Karina; Fidel, Rivail Antonio Sergio; Luna, Aderval Severino

    2010-09-01

    This study was designed to quantitatively evaluate the amount of dentin debris extruded from the apical foramen by comparing the conventional sequence of the ProTaper Universal nickel-titanium (NiTi) files with the single-file ProTaper F2 technique. Thirty mesial roots of lower molars were selected, and the use of different instrumentation techniques resulted in 3 groups (n=10 each). In G1, a crown-down hand-file technique was used, and in G2 conventional ProTaper Universal technique was used. In G3, ProTaper F2 file was used in a reciprocating motion. The apical finish preparation was equivalent to ISO size 25. An apparatus was used to evaluate the apically extruded debris. Statistical analysis was performed using 1-way analysis of variance and Tukey multiple comparisons. No significant difference was found in the amount of the debris extruded between the conventional sequence of the ProTaper Universal NiTi files and the single-file ProTaper F2 technique (P>.05). In contrast, the hand instrumentation group extruded significantly more debris than both NiTi groups (P<.05). The present results yielded favorable input for the F2 single-file technique in terms of apically extruded debris, inasmuch as it is the most simple and cost-effective instrumentation approach. Copyright (c) 2010 Mosby, Inc. All rights reserved.

  7. 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.

  8. Influence of ceria on the thermally durability of Pt/Rh automotive catalyst

    International Nuclear Information System (INIS)

    Muraki, H.; Zhang, G.

    1998-01-01

    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

  9. In Vitro Comparison of Apically Extruded Debris during Root Canal Preparation of Mandibular Premolars with Manual and Rotary Instruments.

    Science.gov (United States)

    Soi, Sonal; Yadav, Suman; Sharma, Sumeet; Sharma, Mohit

    2015-01-01

    Background and aims. During root canal preparation, debris extruded beyond the apical foramen may result in periapical inflammation and postoperative pain. To date no root canal preparation method has been developed that extrudes no periapical debris. The purpose of this study was to identify a system leading to minimal extrusion of debris from the apical foramen. The study was conducted to comparatively evaluate the amount of apical extrusion of debris during root canal preparation using hand ProTaper and GT rotary and RaCe rotary instruments using crown-down technique. Materials and methods. Ninety freshly extracted human single-rooted mandibular premolars were equally assigned to three groups (n=30). The root canals were instrumented using hand ProTaper, GT rotary and RaCe rotary systems. Debris and irrigant extruded from the apical foramen were collected into vials. The mean weight of the remaining debris was calculated for each group and subjected to statistical analysis. Results. ANOVA was used to compare the mean dry weights of the debris extruded in the three groups, followedby post hoc Tukey tests for multiple comparisons the between groups. Highly significant differences were found in the amount of debris extruded among all the groups (PProTaper group exhibited the highest mean debris weight (0.8293±0.05433 mg) and the RaCe system exhibited the lowest mean debris weight (0.1280±0.01606 mg). Conclusion. All the systems tested resulted in apical extrusion of debris. However, the hand ProTaper files extruded a significantly higher amount of debris than GT and RaCe systems.

  10. Parameters Affecting the Extraction Process of Jatropha curcas Oil Using a Single Screw Extruder

    Directory of Open Access Journals (Sweden)

    Ali Nurrakhmad Siregar

    2015-07-01

    Full Text Available The most commonly used technique to separate oil and cake from J. curcas seeds is mechanical extraction. It uses simple tools such as a piston and a screw extruder to produce high pressure, driven by hand or by engine. A single screw extruder has one screw rotating inside the barrel and materials simultaneously flow from the feed to the die zone. The highest oil yield can be obtained by a well-designed oil press as well as finding the optimum conditions for all parameters involved during the extraction process. The influence of the parameters in a single screw extruder was studied using finite element analysis and computational fluid dynamics simulation with ANSYS POLYFLOW. The research focused on predicting the velocity, pressure and shear rate in the metering section that influenced the screw rotational speed and mass flow rate. The obtained results revealed that increasing the screw rotational speed will increase the pressure, velocity and shear rate. Meanwhile, increasing the mass flow rate results in decreasing the pressure while the velocity and shear rate remain constant.

  11. Weight analyses and nitrogen balance assay in rats fed extruded ...

    African Journals Online (AJOL)

    Weight analyses and nitrogen balance assay in adult rats in raw and extruded African breadfruit (Treculia africana) based diets were carried out using response surface methodology in a central composite design. Process variables were feed composition (40 - 100 % African breadfruit, 0 - 5 % corn and 0 - 55 % soybean, ...

  12. 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.

  13. Hydrogen production from bio-fuels using precious metal catalysts

    Science.gov (United States)

    Pasel, Joachim; Wohlrab, Sebastian; Rotov, Mikhail; Löhken, Katrin; Peters, Ralf; Stolten, Detlef

    2017-11-01

    Fuel cell systems with integrated autothermal reforming unit require active and robust catalysts for H2 production. Thus, an experimental screening of catalysts for autothermal reforming of commercial biodiesel fuel was performed. Catalysts consisted of a monolithic cordierite substrate, an oxide support (γ-Al2O3) and Pt, Ru, Ni, PtRh and PtRu as active phase. Experiments were run by widely varying the O2/C and H2O/C molar ratios at different gas hourly space velocities. Fresh and aged catalysts were characterized by temperature programmed methods and thermogravimetry to find correlations with catalytic activity and stability.

  14. Comparison of the amount of apically extruded debris produced by four retreatment techniques: an ex vivo study

    Directory of Open Access Journals (Sweden)

    Cristiane Ferreira Alfenas

    2017-12-01

    Full Text Available Objective: the aim of this study was to compare the amount of apically extruded debris during the removal of root canal filling material using nickel-titanium rotary retreatment instruments and Hedström files. Material and Methods: sixty mandibular incisors with a single canal were instrumented and obturated by cold lateral compaction. For retreatment, specimens were randomly divided into four groups (n = 15: Hedström files with or without solvent; D-RaCe system and Mtwo retreatment system. Debris extruded apically during the removal of canal filling material was collected into preweighed Eppendorf tubes. The tubes were then stored in an incubator at 70°C for 5 days. The weight of the dry extruded debris was established by subtracting the preretreatment and postretreatment weight of the Eppendorf tubes for each group. The mean weights of extruded material were analyzed by one-way ANOVA. Results: the results showed that all retreatment techniques caused apical extrusion of debris, but no statistically significant difference was observed between groups (p>0.05. Conclusion: under the conditions of this study, all retreatment techniques caused apical debris extrusion.

  15. Extruded Tunnel Lining System : Phase 1. Conceptual Design and Feasibility Testing.

    Science.gov (United States)

    1979-09-01

    The Extruded Tunnel Lining System (ETLS) has been conceived as a means of continuously placing the final concrete tunnel lining directly behind a tunnel boring machine. The system will shorten the time required to excavate and line a tunnel section, ...

  16. 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.

  17. Enrichment of rice-based extrudates with Cactus Opuntia dillenii seed powder: a novel source of fiber and antioxidants.

    Science.gov (United States)

    Rayan, Ahmed M; Morsy, Noha E; Youssef, Khaled M

    2018-02-01

    The present study investigated the effects of adding the powder of cactus Opuntia dillenii ( O. dillenii ) seeds on the functional properties, fiber, antioxidants and acceptability of rice-based extrudates. The control blend consisting basically of rice flour was replaced with O. dillenii seed powder at 2, 4, 6, 8, 10, 15 and 20% then extruded at the optimum processing conditions. The extruded products were evaluated for their chemical composition, functional properties, color attributes, antioxidant activity and sensory characteristics. The results revealed that adding O. dillenii seeds powder enhanced the fiber, phenolics, flavonoid contents and antioxidant activity of extrudates. Expansion, bulk density and breaking strength were significantly decreased, while water absorption index, water solubility index and oil absorption index were significantly increased compared to the control. Furthermore, the mean scores of sensory evaluation indicated clear improvements in all tested sensory attributes, which significantly increased by increasing the level of O. dillenii seed powder up to 15%. The results confirmed that O. dillenii seed powder could be incorporated in rice to develop snack products of acceptable functional, nutritional and sensory properties.

  18. Effects of whey protein concentrate, feed moisture and temperature on the physicochemical characteristics of a rice-based extruded flour.

    Science.gov (United States)

    Teba, Carla da Silva; Silva, Erika Madeira Moreira da; Chávez, Davy William Hidalgo; Carvalho, Carlos Wanderlei Piler de; Ascheri, José Luis Ramírez

    2017-08-01

    The influence of whey protein concentrate (WPC), feed moisture and temperature on the physicochemical properties of rice-based extrudates has been investigated. WPC (0.64-7.36g/100g rice) was extruded under 5 moisture (16.64-23.36g/100g) and 5 temperature (106.36-173.64°C) established by a 3 2 central composite rotational design. Physicochemical properties [color, porosimetry, crystallinity, water solubility and absorption, pasting properties, reconstitution test, proximate composition, amino acids, minerals and electrophoresis] were determined. WPC and feed moisture increased redness, yellowness and decreased luminosity. Feed moisture and temperature increased density and total volume pore. WPC and moisture increased crystallinity, but only WPC increased solubility and decrease the retrogradation tendency. Increasing temperature increased the viscosity of the extrudates. The addition of WPC improved the nutritional composition of the extrudates, especially proteins. It is suggested that the extrusion process positively affected the retention of most of the polypeptides chains. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Effect of thermostable α-amylase injection on mechanical and physiochemical properties for saccharification of extruded corn starch.

    Science.gov (United States)

    Myat, Lin; Ryu, Gi-Hyung

    2014-01-30

    In industry, a jet cooker is used to gelatinize starch by mixing the starch slurry with steam under pressure at 100-175 °C. A higher degree of starch hydrolysis in an extruder is possible with glucoamylase. Unfortunately, it is difficult to carry out liquefaction and saccharification in parallel, because the temperature of gelatinization will be too high and will inactivate glucoamylase. Since the temperature for liquefaction and saccharification is different, it is hard to change the temperature from high (required for liquefaction) to low (required for saccharification). The industrial gelatinization process is usually carried out with 30-35% (w/w) dry solids starch slurry. Conventional jet cookers cannot be used any more at high substrate concentrations owing to higher viscosity. In this study, therefore, corn starch was extruded at different melt temperatures to overcome these limitations and to produce the highest enzyme-accessible starch extrudates. Significant effects on physical properties (water solubility index, water absorption index and color) and chemical properties (reducing sugar and % increase in reducing sugar after saccharification) were achieved by addition of thermostable α-amylase at melt temperatures of 115 and 135 °C. However, there was no significant effect on % increase in reducing sugar of extruded corn starch at 95 °C. The results show the great potential of extrusion with thermostable α-amylase injection at 115 and 135 °C as an effective pretreatment for breaking down starch granules, because of the significant increase (P < 0.05) in % reducing sugar and enzyme-accessible extrudates for saccharification yield. © 2013 Society of Chemical Industry.

  20. Fuzzy logic application for extruders replacement problem

    Directory of Open Access Journals (Sweden)

    Edison Conde Perez dos Santos

    2017-03-01

    Full Text Available In a scenario of uncertainty and imprecision, before taking the replacement analysis, a manager needs to consider the uncertain reality of a problem. In this scenario, the fuzzy logic makes an excellent option. Therefore, it is necessary to make a decision based on the fuzzy model. This study is based on the comparison of two methodologies used in the problem of asset replacement. The study, thus, was based on a comparison between two extruders for polypropylene yarn bibliopegy, comparing mainly the costs involved in maintaining the equipment.

  1. 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

    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...

  2. Effect of strontium on the texture and mechanical properties of extruded Mg–1%Mn alloys

    International Nuclear Information System (INIS)

    Borkar, Hemant; Hoseini, Majid; Pekguleryuz, Mihriban

    2012-01-01

    Highlights: ► Mg–1%Mn and Mg–1%Mn–(0.3–2)Sr alloys were extruded at elevated temperature. ► Strontium additions refine extruded microstructure of M1 alloys. ► Sr additions weaken the basal texture of extruded M1, improve the ductility and reduce the yield asymmetry. ► Texture weakening with increasing strontium additions is the result of particle stimulated nucleation (PSN). - Abstract: Magnesium–manganese, M1, alloy is preferred for extrusion applications due to its extrudability. It is mainly used as a sacrificial anode or as a creep resistant alloy at elevated temperatures in the nuclear industry. Since Mn does not provide a significant strengthening effect, the alloy is not considered for structural applications. The basal texture which forms after extrusion orients the basal planes parallel to the extrusion direction causing anisotropy in mechanical properties. This basal texture, as well as the low strength of the alloy are the main challenges in its widespread applications. In this study, the effect of Sr addition on the texture and mechanical properties of M1 alloy was studied. M1–Sr alloys showed weakened texture by developing random texture components during extrusion. The texture randomisation is attributed to particle stimulated nucleation (PSN) around Mg–Sr intermetallics during recrystallisation. M1–Sr compositions are found to show improved strength and ductility as well as reduced yield asymmetry.

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

    Directory of Open Access Journals (Sweden)

    Rolando José González

    2013-01-01

    Full Text Available 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.

  4. In Vitro Comparison of Apically Extruded Debris during Root Canal Preparation of Mandibular Premolars with Manual and Rotary Instruments

    Directory of Open Access Journals (Sweden)

    Sonal Soi

    2015-09-01

    Full Text Available Background and aims. During root canal preparation, debris extruded beyond the apical foramen may result in periapical inflammation and postoperative pain. To date no root canal preparation method has been developed that extrudes no peri-apical debris. The purpose of this study was to identify a system leading to minimal extrusion of debris from the apical fo-ramen. The study was conducted to comparatively evaluate the amount of apical extrusion of debris during root canal prepa-ration using hand ProTaper and GT rotary and RaCe rotary instruments using crown-down technique. Materials and methods. Ninety freshly extracted human single-rooted mandibular premolars were equally assigned to three groups (n=30. The root canals were instrumented using hand ProTaper, GT rotary and RaCe rotary systems. Debris and irrigant extruded from the apical foramen were collected into vials. The mean weight of the remaining debris was calcu-lated for each group and subjected to statistical analysis. Results. ANOVA was used to compare the mean dry weights of the debris extruded in the three groups, followedby post hoc Tukey tests for multiple comparisons the between groups. Highly significant differences were found in the amount of debris extruded among all the groups (P<0.001. The ProTaper group exhibited the highest mean debris weight (0.8293±0.05433 mg and the RaCe system exhibited the lowest mean debris weight (0.1280±0.01606 mg. Conclusion. All the systems tested resulted in apical extrusion of debris. However, the hand ProTaper files extruded a sig-nificantly higher amount of debris than GT and RaCe systems.

  5. In Vitro Comparison of Apically Extruded Debris during Root Canal Preparation of Mandibular Premolars with Manual and Rotary Instruments

    Science.gov (United States)

    Soi, Sonal; Yadav, Suman; Sharma, Sumeet; Sharma, Mohit

    2015-01-01

    Background and aims. During root canal preparation, debris extruded beyond the apical foramen may result in periapical inflammation and postoperative pain. To date no root canal preparation method has been developed that extrudes no periapical debris. The purpose of this study was to identify a system leading to minimal extrusion of debris from the apical foramen. The study was conducted to comparatively evaluate the amount of apical extrusion of debris during root canal preparation using hand ProTaper and GT rotary and RaCe rotary instruments using crown-down technique. Materials and methods. Ninety freshly extracted human single-rooted mandibular premolars were equally assigned to three groups (n=30). The root canals were instrumented using hand ProTaper, GT rotary and RaCe rotary systems. Debris and irrigant extruded from the apical foramen were collected into vials. The mean weight of the remaining debris was calculated for each group and subjected to statistical analysis. Results. ANOVA was used to compare the mean dry weights of the debris extruded in the three groups, followedby post hoc Tukey tests for multiple comparisons the between groups. Highly significant differences were found in the amount of debris extruded among all the groups (P<0.001). The ProTaper group exhibited the highest mean debris weight (0.8293±0.05433 mg) and the RaCe system exhibited the lowest mean debris weight (0.1280±0.01606 mg). Conclusion. All the systems tested resulted in apical extrusion of debris. However, the hand ProTaper files extruded a significantly higher amount of debris than GT and RaCe systems. PMID:26697144

  6. exploration the extrudability of aluminum matrix composite (lm6/tic)

    African Journals Online (AJOL)

    lanez

    2017-11-24

    Nov 24, 2017 ... Aluminum matrix composites (LM6/TiC) is a mix of excellent properties of aluminum casting alloy (LM6), and particles of (TiC) which make it the first choice in many applications like airplane and marine industries. During this research the extrudability and mechanical specifications of this composite ...

  7. Hydrogen production from bio-fuels using precious metal catalysts

    Directory of Open Access Journals (Sweden)

    Pasel Joachim

    2017-01-01

    Full Text Available Fuel cell systems with integrated autothermal reforming unit require active and robust catalysts for H2 production. Thus, an experimental screening of catalysts for autothermal reforming of commercial biodiesel fuel was performed. Catalysts consisted of a monolithic cordierite substrate, an oxide support (γ-Al2O3 and Pt, Ru, Ni, PtRh and PtRu as active phase. Experiments were run by widely varying the O2/C and H2O/C molar ratios at different gas hourly space velocities. Fresh and aged catalysts were characterized by temperature programmed methods and thermogravimetry to find correlations with catalytic activity and stability.

  8. Development of functional extruded snacks by utilizing paste shrimp (Acetes spp.): process optimization and quality evaluation.

    Science.gov (United States)

    Kumar, Raushan; Xavier, Ka Martin; Lekshmi, Manjusha; Dhanabalan, Vignaesh; Thachil, Madonna T; Balange, Amjad K; Gudipati, Venkateshwarlu

    2018-04-01

    Functional extruded snacks were prepared using paste shrimp powder (Acetes spp.), which is rich in protein. The process variables required for the preparation of extruded snacks was optimized using response surface methodology. Extrusion temperature (130-144 °C), level of Acetes powder (100-200 g kg -1 ) and feed moisture (140-200 g kg -1 ) were selected as design variables, and expansion ratio, porosity, hardness, crispness and thiobarbituric acid reactive substance value were taken as the response variables. Extrusion temperature significantly influenced all the response variables, while Acetes inclusion influenced all variables except porosity. Feed moisture content showed a significant quadratic effect on all responses and an interactive effect on expansion ratio and hardness. Shrimp powder incorporation increased the protein and mineral content of the final product. The extruded snack made with the combination of extrusion temperature 144.59 °C, feed moisture 178.5 g kg -1 and Acetes inclusion level 146.7 g kg -1 was found to be the best one based on sensory evaluation. The study suggests that use of Acetes species for the development of extruded snacks will serve as a means of utilization of Acetes as well as being a rich source of proteins for human consumption, which would otherwise remain unexploited as a by-catch. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  9. Catalyst Stability Benchmarking for the Oxygen Evolution Reaction: The Importance of Backing Electrode Material and Dissolution in Accelerated Aging Studies.

    Science.gov (United States)

    Geiger, Simon; Kasian, Olga; Mingers, Andrea M; Nicley, Shannon S; Haenen, Ken; Mayrhofer, Karl J J; Cherevko, Serhiy

    2017-09-18

    In searching for alternative oxygen evolution reaction (OER) catalysts for acidic water splitting, fast screening of the material intrinsic activity and stability in half-cell tests is of vital importance. The screening process significantly accelerates the discovery of new promising materials without the need of time-consuming real-cell analysis. In commonly employed tests, a conclusion on the catalyst stability is drawn solely on the basis of electrochemical data, for example, by evaluating potential-versus-time profiles. Herein important limitations of such approaches, which are related to the degradation of the backing electrode material, are demonstrated. State-of-the-art Ir-black powder is investigated for OER activity and for dissolution as a function of the backing electrode material. Even at very short time intervals materials like glassy carbon passivate, increasing the contact resistance and concealing the degradation phenomena of the electrocatalyst itself. Alternative backing electrodes like gold and boron-doped diamond show better stability and are thus recommended for short accelerated aging investigations. Moreover, parallel quantification of dissolution products in the electrolyte is shown to be of great importance for comparing OER catalyst feasibility. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Utilization of smoked salmon trim in extruded smoked salmon jerky.

    Science.gov (United States)

    Kong, J; Dougherty, M P; Perkins, L B; Camire, M E

    2012-06-01

    During smoked salmon processing, the dark meat along the lateral line is removed before packaging; this by-product currently has little economic value. In this study, the dark meat trim was incorporated into an extruded jerky. Three formulations were processed: 100% smoked trim, 75% : 25% smoked trim : fresh salmon fillet, and 50% : 50% smoked trim : fresh salmon blends (w/w basis). The base formulation contained salmon (approximately 83.5%), tapioca starch (8%), pregelatinized potato starch (3%), sucrose (4%), salt (1.5%), sodium nitrate (0.02%), and ascorbyl palmitate (0.02% of the lipid content). Blends were extruded in a laboratory-scale twin-screw extruder and then hot-smoked for 5 h. There were no significant differences among formulations in moisture, water activity, and pH. Protein was highest in the 50 : 50 blend jerky. Ash content was highest in the jerky made with 100% trim. Total lipids and salt were higher in the 100% trim jerky than in the 50 : 50 blend. Hot smoking did not adversely affect docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) content in lipids from 100% smoked trim jerky. Servings of salmon jerky made with 75% and 100% smoked trim provided at least 500 mg of EPA and DHA. The 50 : 50 formulation had the highest Intl. Commission on Illumination (CIE) L*, a*, and b* color values. Seventy consumers rated all sensory attributes as between "like slightly" and "like moderately." With some formulation and processing refinements, lateral line trim from smoked salmon processors has potential to be incorporated into acceptable, healthful snack products. Dark meat along the lateral line is typically discarded by smoked salmon processors. This omega-3 fatty acid rich by-product can be used to make a smoked salmon jerky that provides a convenient source of these healthful lipids for consumers. © 2012 Institute of Food Technologists®

  11. Processing and characterization of extruded breakfast meal formulated with broken rice and bean flour

    Directory of Open Access Journals (Sweden)

    Ana Vânia Carvalho

    2012-09-01

    Full Text Available The objective of this work was to develop an extruded breakfast product containing broken rice and split old beans and to verify the influence of the extrusion process on their physicochemical, technological, and sensory characteristic. The final product had a protein content of 9.9 g.100 g-1, and therefore it can be considered a good source of proteins for children and teenagers. The dietary fiber content of the final edible product was 3.71 g.100 g-1. Therefore, the breakfast meal may be considered as a source of dietary fiber according to Brazilian law . As for the technological properties, the extruded product presented an expansion index of 8.89 and apparent density of 0.25 g.cm-3. With regard to the sensory analysis, the acceptance average was ranked between 6.8 and 7.7, corresponding to the categories "liked slightly" and "liked very much". With regard to purchase intention, 79% of the panelists said they would certainly or possibly purchase the product. Broken rice and split old beans are interesting alternatives for the elaboration of extruded breakfast products presenting good nutritional, technological, and sensory qualities.

  12. Evaluation of apically extruded debris during removal of gutta-percha and ResilonTM using different instrumentation techniques

    Directory of Open Access Journals (Sweden)

    Pešić Dragana

    2018-01-01

    Full Text Available Background/Aim. Apical extrusion of material is considered as one of the very important factor for endodontic treatment success. Microorganisms, necrotic tissue, filling material and irrigants, which can be extruded apically during endodontic retreatment, may jeopardize the success of the therapy. The aim of this in vitro study was to quantitatively evaluate the amount of apically extruded debris during endodontic retreatment of teeth obturated with two different materials, using one hand and three rotary instrumentation techniques. Methods. Ninety-six extracted single-rooted teeth were endodontically treated and enlarged to size 40 using BioRaCe system, and then randomly divided into 8 groups of 12 specimens each. Half of the specimens were obturated with gutta-percha and AH Plus® sealer and another half with RealSeal SE system, using lateral condensation technique. Retreatment was performed using: Hedström files; ProFile rotary files; ProTaper Retreatment system and D-RaCe system. Apically extruded debris was collected in pre-weighed Eppendorf tubes and evaluated using an electronic microbalance. Data were analyzed statistically using t-test and analysis of variance. Results. In the AH Plus/gutta-percha group, all tested rotary instruments gave significantly less extruded debris compared with Hedström files (p < 0.05. In theRealSeal group, there was significant difference between DRaCe and Hedström instruments (p < 0.05. Conclusion. All retreatment techniques resulted in apical extrusion. DRaCe system produced significantly less extruded debris compared to hand files. No significant difference was found when comparing two instruments specially designed for retreatment: D-RaCe and ProTaper systems.

  13. Iron, zinc and calcium dialyzability from extruded product based on whole grain amaranth (Amaranthus caudatus and Amaranthus cruentus) and amaranth/Zea mays blends.

    Science.gov (United States)

    Galan, María Gimena; Drago, Silvina Rosa; Armada, Margarita; José, Rolando González

    2013-06-01

    Amaranth is a Native American grain appreciated for its high nutritional properties including high mineral content. The aim of this study was to evaluate the availability of Fe, Zn and Ca from extruded products made with two varieties of amaranth and their mixtures with maize at two levels of replacement. Mineral availability was estimated using dialyzability method. The contents of Fe (64.0-84.0 mg/kg), Ca (1977.5-2348.8 mg/kg) and Zn (30.0-32.1 mg/kg) were higher in amaranth than in maize products (6.2, 19.1, 9.7 mg/kg, respectively). Mineral availability was in the range of (2.0-3.6%), (3.3-11.1%) and (1.6-11.4%) for Fe, Ca and Zn, respectively. Extruded amaranth and amaranth/maize products provide higher amount of Fe and Ca than extruded maize. Extruded amaranth products and amaranth addition to maize could be an interesting way to increase nutritional value of extruded products.

  14. Extrusion trials with a TSK045 twin screw extruder (Poster presentation)

    NARCIS (Netherlands)

    Sabel, H.W.R.; Schonewille, E.

    1998-01-01

    In 1994 a 45mm twin screw extruder was introduced at the Prins Maurits Laboratory of TNO for the processing of energetic materials. Initial safety experiments were carried out by using inert compositions with small amounts of different energetic components and micro encapsulated chemical sensors to

  15. Growth and Nutrient Utilization in Kids Fed Expander-extruded Complete Feed Pellets Containing Red Gram ( Straw

    Directory of Open Access Journals (Sweden)

    P. B. Reddy

    2012-12-01

    Full Text Available 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 of eight each and were fed for 150 d with four experimental diets (T1: mash with 35% RGS, T2: mash with 50% RGS, T3: pellets with 35% RGS and T4: pellets with 50% RGS. Pelleting of complete diets significantly (p<0.001 increased the voluntary feed intake (671.45 vs 426.28 g/d at both levels of RGS in the feeds. Average daily gain (ADG, g/d also increased significantly (p<0.001 from 48.79 in kids fed mash diet to 71.29 in those fed with pelleted diets. Feed conversion efficiency (dry matter (DM intake: weight gain was comparable among all the treatment groups. Digestibility of nutrients was not affected by pelleting of the feeds whereas, increasing the level of inclusion of RGS in feeds from 35% to 50% decreased (p<0.05 the digestibility of DM and crude protein (CP resulting in lower (p<0.001 metabolizable energy (ME content (MJ/kg DM in feeds with 50% RGS (7.93 vs 8.75. Daily intake (MJ/kg BW−0.75 of ME decreased (p<0.05 in feeds containing 50% RGS while pelleting of feeds increased (p<0.05 the intake of DM, CP, digestible crude protein (DCP and ME. It is inferred that expander extruder pelleting can efficiently utilize RGS up to 50% level in complete diets for growing goat kids.

  16. Identification of potent odorants formed during the preparation of extruded potato snacks.

    Science.gov (United States)

    Majcher, Małgorzata A; Jeleń, Henryk H

    2005-08-10

    Extrusion cooking processing followed by air-drying has been applied to obtain low-fat potato snacks. Optimal parameters were developed for a dough recipe. Dough contained apart from potato granules 7% of canola oil, 1% of salt, 1% of baking powder, 5% of maltodextrin, and 15% of wheat flour. After the extrusion process, snacks were dried at 85 degrees C for 15 min followed by 130 degrees C for 45 min. The potent odorants of extruded potato snacks were identified using aroma extract dilution analysis and gas chromatography-olfactometry. Among the characteristic compounds, methional with boiled potato flavor, benzenemethanethiol with pepper-seed flavor, 2-acetyl-1-pyrroline with popcorn flavor, benzacetaldehyde with strong flowery flavor, butanal with rancid flavor, and 2-acetylpyrazine with roasty flavor were considered to be the main contributors to the aroma of extruded potato snacks. Several compounds were concluded to be developed during extrusion cooking, such as ethanol, 3-methylbutanal, (Z)-1,5-octadien-3-one with geranium flavor, and unknown ones with the flavor of boiled potato, cumin, candy, or parsley root. Compounds such as methanethiol, 2,3-pentanedione, limonene, 2-acetylpyrazine, 2-ethyl-3,5-dimethylpyrazine, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, 2-methyl-3,5-diethylpyrazine, 5-methyl-2,3-diethylpyrazine, and (E)-beta-damascenone were probably developed during air-drying of the potato extrudate.

  17. Physical properties and FTIR analysis of rice-oat flour and maize-oat flour based extruded food products containing olive pomace.

    Science.gov (United States)

    Ying, DanYang; Hlaing, Mya Myintzu; Lerisson, Julie; Pitts, Keith; Cheng, Lijiang; Sanguansri, Luz; Augustin, Mary Ann

    2017-10-01

    Olive pomace, a waste stream from olive oil processing, was fractionated by centrifugation to obtain a supernatant and a flesh-enriched fraction, and freeze dried to obtain a powder. The dried supernatant contained 5.8% moisture, 4.8% protein, 3.5% fat, 3.5% ash, 82.4% carbohydrate (including 17.2% dietary fiber) and polyphenols (2970mg gallic acid equivalents (GAE)/100g). The dried flesh-enriched fraction, contained 5.9% moisture, 13.4% protein, 14.2% fat, 3.5% ash, 63.1% carbohydrate (including 42.7% dietary fiber) and polyphenols (1960mg GAE/100g). The extruded products using rice-oat flour or maize-oat flour mixtures as the base were formulated to contain 5% or 10% olive pomace fractions (dry basis). The extruded products with added olive pomace fractions has higher fiber (2-7g/100g) and polyphenol contents (67-161mg GAE/100g) compared to the corresponding mixtures of rice-oat flour base (0.92g/100g fiber, 20mg GAE/100g) or maize-oat flour base (3.2g/100g fiber, 20mg GAE/100g) without olive pomace fractions. Addition of olive pomace fractions reduced the die pressure and specific mechanical energy during extrusion and resulted in lower radial expansion in the extruded product. The impact of the addition of olive pomace fraction on physical characteristics of the extruded product is higher for rice-oat flour base than maize-oat flour base. The underlining mechanism was explained by FTIR analysis. FTIR showed that there were significant changes in the carbohydrate components and the structure of the proteins on extrusion, with consequent effects on the expansion and density of the extruded product. This study showed the feasibility of preparing fiber and polyphenol enriched extruded products by incorporation of olive pomace. This shows the potential of recovery and diversion of edible components from waste streams of olive oil processing for formulation of extruded products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Metallization of Extruded Briquettes (BREX in Midrex Process

    Directory of Open Access Journals (Sweden)

    Aitber Bizhanov

    2017-07-01

    Full Text Available The results of the full-scale testing of the Extruded Briquettes (BREX as the charge components of the industrial Midrex reactor are discussed. The influence of the type of binder on the degree of metallization of BREX is analyzed. Magnesium sulfate-based binder helps to reach highest metallization degree of BREX. Mineralogical study shows the difference in the iron-silicate phase’s development as well as in the porosity change during metallization depending on the binder used.

  19. Extrusion of blends of cassava leaves and cassava flour: physical characteristics of extrudates

    Directory of Open Access Journals (Sweden)

    Cristiane da Cunha Salata

    2014-09-01

    Full Text Available A cassava-based puffed snack was produced using a single screw extruder to determine the effect of the raw material composition (cassava leaf flour and moisture and the process parameters (extrusion temperature and screw speed on the physical characteristics of an extruded-expanded snack. A central composite rotational design, including four factors with 30 treatments, was used with the following as dependent variables: expansion index, specific volume, water solubility index, water absorption index, color (L*, a*, b*, and hardness. Under conditions of low moisture content (12 to 14%, low percentage of cassava leaf flour (2 to 4%, and intermediate conditions of extrusion temperature (100°C and screw speed (230rpm, it was possible to obtain puffed snack products with desirable characteristics.

  20. Effect of feed composition, moisture content and extrusion temperature on extrudate characteristics of yam-corn-rice based snack food.

    Science.gov (United States)

    Seth, Dibyakanta; Badwaik, Laxmikant S; Ganapathy, Vijayalakshmi

    2015-03-01

    Blends of yam, rice and corn flour were processed in a twin-screw extruder. Effects of yam flour (10-40 %), feed moisture content (12-24 %) and extruder barrel temperature (100-140 °C) on the characteristics of the dried extrudates was investigated using a statistical technique response surface methodology (RSM). Radial expansion ratio differed significantly (p ≤ 0.05) with change in all the independent variables. Highest expansion (3.97) was found at lowest moisture content (12 %) and highest barrel temperature (140 °C). Increased yam flour level decreased the expansion ratio significantly. Water absorption index (WAI) increased significantly with increase of all variables. However, water solubility index (WSI) did not change with change in yam flour percent. Hardness of extrudates that varied from 3.86 to 6.94 N was positively correlated with yam flour level and feed moisture content, however it decreased significantly (p ≤ 0.001) with increase of barrel temperature. Yam percent of 15.75 with feed moisture and barrel temperature at 12.00 % and 140 °C respectively gave an optimized product of high desirability (> 0.90) with optimum responses of 3.29 expansion ratio, 5.64 g/g dry solid water absorption index, 30.39 % water solubility index and 3.86 N hardness. The predicted values registered non-significant (p extruded snacks and little emphasis on the chemistry of interaction between different components.

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

    KAUST Repository

    Renard, Laetitia; El Eter, Mohamad; Caps, Valerie; Basset, Jean-Marie

    2014-01-01

    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.

  2. 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.

  3. Apically Extruded Debris during Root Canal Instrumentation with Reciproc Blue, HyFlex EDM, and XP-endo Shaper Nickel-titanium Files.

    Science.gov (United States)

    Uslu, Gülşah; Özyürek, Taha; Yılmaz, Koray; Gündoğar, Mustafa; Plotino, Gianluca

    2018-05-01

    The purpose of this study was to investigate the amount of apically extruded debris by Reciproc Blue (REC Blue; VDW, Munich, Germany), HyFlex EDM (HEDM; Coltene/Whaledent, Altstätten, Switzerland), and XP-endo Shaper (XPS; FKG Dentaire SA, La Chaux-de-Fonds, Switzerland) files during root canal preparation at body temperature. Sixty extracted single-rooted mandibular premolar human teeth were randomly assigned to 3 groups (n = 20). The canals were instrumented using 1 of the following instruments: REC Blue, HEDM, or XPS. Apically extruded debris during instrumentation was collected into preweighed Eppendorf tubes. All the procedures were performed at 35°C. The amount of extruded debris was calculated by subtracting the weight value of the tooth-free apparatus from the postpreparation weight value. The data were analyzed using the Kruskal-Wallis test at a 5% significance level. All the instruments tested caused extrusion of some debris from the apical foramen. XPS extruded significantly less debris from the apex than REC Blue (P  .05). Within the limitations of this in vitro study, the amount of apically extruded debris registered for the different files tested was REC Blue > HEDM > XPS, with a statistical difference only between XPS and REC Blue. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  4. Cobalt and KNO3 supported on alumina catalysts for diesel soot combustion

    International Nuclear Information System (INIS)

    Grzona, Claudia B.; Lick, Ileana D.; Castellon, Enrique Rodriguez; Ponzi, Marta I.; Ponzi, Esther N.

    2010-01-01

    The catalytic combustion of diesel soot was studied in the presence of fresh and aged catalysts: Co/Al 2 O 3 , KNO 3 /Al 2 O 3 and Co/KNO 3 /Al 2 O 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 2 and O 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 3 and the role of this salt can be attributed to the contribution of NO 3 - /NO 2 - redox cycle.

  5. Effects of different cooling rates during two casting processes on the microstructures and mechanical properties of extruded Mg–Al–Ca–Mn alloy

    International Nuclear Information System (INIS)

    Xu, S.W.; Oh-ishi, K.; Kamado, S.; Takahashi, H.; Homma, T.

    2012-01-01

    Highlights: ► Ordered monolayer GP zone was formed by increasing cooling rate. ► Finer extruded microstructure was obtained by increasing cooling rate. ► Higher number density precipitates was obtained by increasing cooling rate. ► Tensile 0.2% proof stress was increased by 105 MPa by increasing cooling rate. ► Extruded DC-cast alloy shows higher tensile 0.2% proof stress of 409 MPa. - Abstract: In this study, Mg–3.6Al–3.4Ca–0.3Mn (wt.%) (which is denoted AXM4303) alloy ingots were prepared by two casting processes with different cooling rates: permanent mold (PM) casting, which has a lower cooling rate of 10–20 °C/s and direct chill (DC) casting, which has a higher cooling rate of 100–110 °C/s. Then, these two types of AXM4303 alloy ingots were hot extruded at 400 °C under the same conditions. The microstructures of the as-cast and extruded alloy samples were systematically investigated by field-emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM) and electron backscattered diffraction (EBSD) systems. The effects of the different cooling rates during the casting process on the microstructures and mechanical properties of the extruded AXM4303 alloy samples were evaluated. The results show that the strength of the extruded Mg–Al–Ca–Mn alloy can be substantially increased by microstructural control during the casting process. Because the cooling rate of the DC casting process is much faster than the cooling rate of PM casting, the DC-cast AXM4303 has the following properties: (i) the lamellar eutectic structure and dendrite cell size are significantly refined, (ii) the ordered monolayer GP zones enriched with Al and Ca nucleate with no growth, and (iii) most of the Mn remains in solution in the matrix. Thus, after hot extrusion, the DC-cast AXM4303 has finer dynamically recrystallized (DRXed) grain size, finer and more uniformly distributed fragmented eutectic particles, finer planar Al 2 Ca precipitates

  6. Evaluation of apically extruded debris during root canal preparation in primary molar teeth using three different rotary systems and hand files.

    Science.gov (United States)

    Topçuoğlu, Gamze; Topçuoğlu, Hüseyin Sinan; Akpek, Firdevs

    2016-09-01

    To assess the amount of debris extruded apically during root canal preparation using various nickel titanium instrumentation systems and hand files in primary molar teeth. Sixty extracted primary first mandibular molar human teeth were randomly assigned to four groups (n = 15 teeth for each group). The canals were then instrumented with the following instrument systems: Revo-S, Mtwo, ProTaper Next, and hand files. Apically extruded debris during instrumentation was collected into pre-weighed Eppendorf tubes. The Eppendorf tubes were then stored in an incubator at 70°C for 5 days. The weight of the dry extruded debris was established by subtracting the pre-instrumentation and post-instrumentation weight of the Eppendorf tubes for each group. The data were analyzed using one-way analysis of variance (anova) and Tukey's post hoc tests. ProTaper Next files were associated with less apically extruded debris than the Mtwo, Revo-S, and hand files (P Hand files extruded more debris than Mtwo and Revo-S instruments (P 0.05). All instruments were associated with apical extrusion of debris. ProTaper Next files caused less debris extrusion compared to the other systems used. © 2015 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. 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.

  8. Cofortification of ferric pyrophosphate and citric acid/trisodium citrate into extruded rice grains doubles iron bioavailability through in situ generation of soluble ferric pyrophosphate citrate complexes.

    Science.gov (United States)

    Hackl, Laura; Cercamondi, Colin I; Zeder, Christophe; Wild, Daniela; Adelmann, Horst; Zimmermann, Michael B; Moretti, Diego

    2016-05-01

    Iron fortification of rice is a promising strategy for improving iron nutrition. However, it is technically challenging because rice is consumed as intact grains, and ferric pyrophosphate (FePP), which is usually used for rice fortification, has low bioavailability. We investigated whether the addition of a citric acid/trisodium citrate (CA/TSC) mixture before extrusion increases iron absorption in humans from FePP-fortified extruded rice grains. We conducted an iron absorption study in iron-sufficient young women (n = 20), in which each participant consumed 4 different meals (4 mg Fe/meal): 1) extruded FePP-fortified rice (No CA/TSC); 2) extruded FePP-fortified rice with CA/TSC added before extrusion (CA/TSC extruded); 3) extruded FePP-fortified rice with CA/TSC solution added after cooking and before consumption (CA/TSC solution); and 4) nonextruded rice fortified with a FeSO4 solution added after cooking and before consumption (reference). Iron absorption was calculated from erythrocyte incorporation of stable iron isotopes 14 d after administration. In in vitro experiments, we assessed the soluble and dialyzable iron from rice meals in which CA/TSC was added at different preparation stages and from meals with different iron:CA:TSC ratios. Fractional iron absorption was significantly higher from CA/TSC-extruded meals (3.2%) than from No CA/TSC (1.7%) and CA/TSC solution (1.7%; all P solubility and dialyzability were higher in CA/TSC-extruded rice than in rice with No CA/TSC and CA/TSC solution, and solubility increased with higher amounts of added CA and TSC in extruded rice. Iron bioavailability nearly doubled when CA/TSC was extruded with FePP into fortified rice, resulting in iron bioavailability comparable to that of FeSO4 We attribute this effect to an in situ generation of soluble FePP citrate moieties during extrusion and/or cooking because of the close physical proximity of FePP and CA/TSC in the extruded rice matrix. This trial was registered at

  9. Improvement of sulfur resistance of Pd/Ce-Zr-Al-O catalysts for CO oxidation

    Science.gov (United States)

    Shin, Haebin; Baek, Minsung; Ro, Youngsoo; Song, Changyeol; Lee, Kwan-Young; Song, In Kyu

    2018-01-01

    Two kinds of mesoporous ceria-zirconia-alumina supports were prepared by a single-step epoxide-driven sol-gel method (SGCZA) and by a co-precipitation method (PCZA). Palladium catalysts supported on these materials were then prepared by a wet impregnation method (Pd/SGCZA and Pd/PCZA). The prepared catalysts were applied to the CO oxidation reaction before and after sulfur aging. XRD and N2 adsorption-desorption analyses revealed that these two catalysts retained different physicochemical properties. Pd/SGCZA had higher surface area and larger pore volume than Pd/PCZA before and after sulfur aging. TPR (Temperature-programmed reduction), CO chemisorption, FT-IR, and XPS analyses showed that the catalysts were differently influenced by sulfur species. Pd/SGCZA formed less sulfate and retained higher palladium dispersion than Pd/PCZA after sulfur aging. In the CO oxidation, Pd/PCZA showed better activity than Pd/SGCZA before sulfur aging. However, Pd/SGCZA showed higher CO conversion than Pd/PCZA after sulfur aging. We concluded that Pd/SGCZA was less poisoned by sulfur species than Pd/PCZA.

  10. The modeling of continuous mixers. Part I: The corotating twin-screw extruder

    NARCIS (Netherlands)

    Meijer, H.E.H.; Elemans, P.H.M.

    1988-01-01

    In many operations in polymer processing, such as polymer blending, devolatilization, or incorporation of fillers in a polymeric matrix, continuous mixers are used; e.g., corotating twin-screw extruders (ZSK), Buss Cokneaders and Farrel Continuous Mixers. Theoretical analysis of these machines tends

  11. A novel modeling approach to the mixing process in twin-screw extruders

    Science.gov (United States)

    Kennedy, Amedu Osaighe; Penlington, Roger; Busawon, Krishna; Morgan, Andy

    2014-05-01

    In this paper, a theoretical model for the mixing process in a self-wiping co-rotating twin screw extruder by combination of statistical techniques and mechanistic modelling has been proposed. The approach was to examine the mixing process in the local zones via residence time distribution and the flow dynamics, from which predictive models of the mean residence time and mean time delay were determined. Increase in feed rate at constant screw speed was found to narrow the shape of the residence time distribution curve, reduction in the mean residence time and time delay and increase in the degree of fill. Increase in screw speed at constant feed rate was found to narrow the shape of the residence time distribution curve, decrease in the degree of fill in the extruder and thus an increase in the time delay. Experimental investigation was also done to validate the modeling approach.

  12. 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.

  13. Evolution of twinning in extruded AZ31 alloy with bimodal grain structure

    Energy Technology Data Exchange (ETDEWEB)

    Garcés, G., E-mail: ggarces@cenim.csic.es [Department of Physical Metallurgy, National Centre for Metallurgical Research CENIM-CSIC, Av. De Gregorio del Amo 8, 28040 Madrid (Spain); Oñorbe, E. [CIEMAT, Division of Structural Materials, Avenida Complutense, 40, 28040 Madrid (Spain); Gan, W. [German Engineering Materials Science Centre at MLZ, Helmholtz-Zentrum Geesthacht, Lichtebergstr. 1, D-85747 Garching (Germany); Máthis, K. [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University, KeKarlovu 5, 121 16 Praha 2 (Czech Republic); Tolnai, D. [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Horváth, K. [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University, KeKarlovu 5, 121 16 Praha 2 (Czech Republic); Pérez, P.; Adeva, P. [Department of Physical Metallurgy, National Centre for Metallurgical Research CENIM-CSIC, Av. De Gregorio del Amo 8, 28040 Madrid (Spain)

    2017-04-15

    Twinning in extruded AZ31 alloy with a bimodal grain structure is studied under compression along the extrusion direction. This study has combined in-situ measurements during the compression tests by Synchrotron Radiation Diffraction and Acoustic Emission techniques and the evaluation of the microstructure and texture in post-mortem compression samples deformed at different strains. The microstructure of the alloy is characterized by the coexistence of large areas of fine dynamic recrystallized grains and coarse non-recrystallized grains elongated along extrusion direction. Twinning occurs initially in large elongated grains before the macroscopic yield stress which is controlled by the twinning in equiaxed dynamically recrystallized grains. - Highlights: • The AZ31 extruded at low temperature exhibits a bimodal grains structure. • Twinning takes place before macroscopic yielding in coarse non-DRXed grains. • DRXed grains controls the beginning of plasticity in magnesium alloys with bimodal grain structure.

  14. 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...... 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 treating an catalyst for conferring thereon an improved resistance to alkali poisoning....

  15. The Effect of Filler on the Quality of Snack Food Extruded from Solid Matter of Industrial Soybean Tofu

    Directory of Open Access Journals (Sweden)

    Farid Salahudin

    2010-12-01

    Full Text Available Tofu filter cake is the waste of tofu processing which is used for animal feed. In the other hand tofu filter cake can be used at extruded food processing. The purpose of this study is to look for the formulas and filler materials which could produce extruded food. The first variable in this research is the kind of corn that is pop corn and maize corn. The second variable is formulas of filler material that is composition of corn: rice: tofu filter cake = 1:1:0.5; 1:1:0.25; 1:2:0.5 and 1:2:0.25. The result is the formula which can produce best extruded food is pop corn: rice: tofu filter cake = 1:2:0.25 with Expansion Ratio (ER 2.22 and protein content 8.83%.

  16. 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.

  17. Effects of feeding un-extruded floating feed to African giant catfish ...

    African Journals Online (AJOL)

    This study investigated the effects of feeding two types of un-extruded floating fish feeds (HM1 and HM2 –38% CP, produced manually using available feedstuffs) and a commercial imported fish feed (Coppens – 40% CP) on growth performance and body composition of Heterobranchus longifilis over 56 days. Commercial ...

  18. Comparison of Maize Silage-based Diets for Dairy Cows Containing Extruded Rapeseed Cake or Extruded Full-fat Soybean as Major Protein Sources

    Directory of Open Access Journals (Sweden)

    Jiří Třináctý

    2016-01-01

    Full Text Available The trial was carried out on four Holstein cows with initial milk yield of 27.3 ± 1.7 kg.day−1. Cows were divided into two groups – the first was fed a diet based on extruded rapeseed cake (D-ERC, the second one was fed a diet based on extruded full-fat soybean (D-EFFS, both diets contained maize silage and meadow hay. The experiment was divided into 4 periods of 42 days. Intake of dry matter, crude protein and NEL was not affected by the treatment (P > 0.05 while the intake of PDIA, PDIN and PDIE was lower in D-ERC than in D-EFFS (P < 0.05. Milk yield in D-ERC (22.6 kg.d−1 was lower than in D-EFFS (24.7 kg.d−1, P < 0.001 while concentration of milk fat and protein were reverse (P < 0.05. Smaller portion of essential AADI in crude protein intake (CPI in D-ERC resulted in lower efficiency of CPI utilization for milk protein synthesis in comparison to D-EFFS being 313 and 327 g.kg−1, respectively (P < 0.01. Concentration of AA in blood plasma was not affected by the type of diet except of His and Ile that were higher in D-EFFS (P < 0.01.

  19. 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.

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

    International Nuclear Information System (INIS)

    Silva, P.A.; Weber, S.; Inden, G.; Pyzalla, A.R.

    2009-01-01

    Low alloyed steel bars were co-extruded with pre-sintered tool steel powders with the addition of tungsten carbides (W 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 TM ) to investigate the effect of hard particle addition and its dissolution, as well as the formation of M 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 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.

  1. Effect of technological factors on water activity of extruded corn product with an addition of whey proteins.

    Science.gov (United States)

    Makowska, Agnieszka; Cais-Sokolińska, Dorota; Lasik, Agata

    2014-01-01

    The value of water activity in extruded products constitutes a significant indicator of their quality and stability. The state, in which water is found in extruded products, is an indicator of the conducted extrusion process and the used raw material. The aim of the study was to assess water activity in extruded products made from a mixture of com grits with 12.5 and 15.0% moisture contents and different level of addition of whey proteins. It was shown that the degree of mixture moisture content did not have an effect on the value of aw in produced puffs. The greatest difference was recorded when introducing 3% proteins in comparison to aw of puffs produced solely from corn grits. Δaw = 0.023. The greater the content of whey proteins, the lower the aw value. A 3-month storage at a temperature of 18 ±0.5°C influenced aw of snacks produced from a mixture with a higher moisture content.

  2. Optimization of barrel temperature and kidney bean flour percentage based on various physical properties of extruded snacks.

    Science.gov (United States)

    Agathian, G; Semwal, A D; Sharma, G K

    2015-07-01

    The aim of the experiment was to optimize barrel temperature (122 to 178 ± 0.5 °C) and red kidney bean flour percentage (KBF) (12 to 68 ± 0.5 %) based on physical properties of extrudates like flash off percentage, water absorption index (WAI), water solubility index (WSI), bulk density (BD), radial expansion ratio (RER) and overall acceptability (OAA) using single screw extruder. The study was carried out by central composite rotatable design (CCRD) using Response surface methodology (RSM) and moisture content of feed was kept as constant 16.0 ± 0.5 % throughout experiments. Mathematical models for various responses were found to fit significantly (P Extruded snack prepared with rice flour (80 %) and kidney bean flour (20 %) at optimized conditions was accepted by the taste panellists and above 20 % KB incorporation was found to decrease overall acceptability score.

  3. Twin screw extruders as polymerization reactors for a free radical homo polymerization

    NARCIS (Netherlands)

    Ganzeveld, K.J.; Janssen, L.P.B.M.

    The bulk polymerization of n-butylmethacrylate was investigated in a counter-rotating twin screw extruder. It appeared that the gel effect, occurring with bulk polymerizations, affected the polymerization progress very strongly. Due to this effect the conversion of the reaction is independent of the

  4. Extrude Hone deburring with X-base media

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, L.K.

    1973-09-01

    Small precision mechanisms must have burr-free, sharp-edged parts to operate well. Controlling the size of burrs can lower burr removal costs and improve edge repeatability. Study results indicated that with conventional tooling approaches, Extrude Hone deburring with x-base media removes more material from the hole than desired and is less repeatable than required on precision miniature parts. With this media, the process is most applicable to precision miniature parts with burrs less than 25.4 ..mu..m thick, allowable hole size changes equal to burr thickness, and allowable hole size repeatability of +-0.2 times the actual average hole size change.

  5. Characterization and Regeneration of Pt-Catalysts Deactivated in Municipal Waste Flue Gas

    DEFF Research Database (Denmark)

    Rasmussen, Søren Birk; Kustov, Arkadii; Due-Hansen, Johannes

    2006-01-01

    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 H-2/N-2 gas to the off-gas can completely restore...... the activity of the deactivated catalysts. (c) 2006 Elsevier B.V. All rights reserved....

  6. Study of Catalyst, Aging Time and Surfactant Effects on Silica Inorganic Polymer Characteristics

    Directory of Open Access Journals (Sweden)

    M. Pakizeh

    2007-06-01

    Full Text Available In the present study the sol-gel method is used for synthesis of amorphous nanostructure silica polymer using tetraethoxysilane (TEOS as silicon source. This polymer can be used in manufacturing of nanoporous asymmetricmembranes. The effect of catalyst on silica particle size has been studied under acidic and basic conditions.زAcid-catalyzed reaction leads to the formation of fine particles while the base-catalyzed reaction produceslarger particles. The presence of cationic template surfactant namely cetyl pyridinium bromide (CPBزdirects the structural formation of the polymer by preventing the highly branched polymeric clusters. This will increase the effective area of the produced silica membrane. Nitrogen physisorption tests by Brunaver- Emmett-Teller (BET and Barrett-Joyner-Halenda (BJH methods revealed that the surface area of the membrane increases significantly around 5-folds when acid-catalyzed reaction is used. 29Si-NMR test is also used to study the aging time effect on the level of silica polymer branching. The results show that in acidic condition, aging time up to three weeks can still affect branching. The calcinations process in which the organic materials and CPB (surfactant are burned and released from the silica particles, is studied on template free silica materials as well as templated silica materials using TGA and DTA techniques.

  7. Tailored sPP/Silica Nanocomposite for Ecofriendly Insulation of Extruded HVDC Cable

    Directory of Open Access Journals (Sweden)

    Bin Dang

    2015-01-01

    Full Text Available Cross-linked polyethylene (XLPE is a thermosetting material that cannot be recycled at the end of its lifetime. This study investigated the potential of syndiotactic polypropylene (sPP/silica as an ecofriendly extruded insulation system for HVDC cables. We investigated the morphology, Fourier transform infrared, and thermal, thermomechanical, and electrical behaviors of sPP modified with 0.5–3% nanosilica. We found that the silica/sPP nanocomposite without cross-linking offered a suitable mechanical modulus at room temperature and sufficient intensity at high temperatures, and adding nanosilica modified by a silane coupling agent to the sPP resulted in significant DC resistivity and space charge improvement. The optimal nanosilica content in the sPP was determined by balancing the mechanical and thermomechanical characteristics and the DC resistivity. The sPP/silica nanocomposite reported here shows great potential as a candidate insulation material for future ecofriendly extruded HVDC cables.

  8. Semi-continuous anaerobic digestion of extruded OFMSW: Process performance and energetics evaluation.

    Science.gov (United States)

    Mu, Lan; Zhang, Lei; Zhu, Kongyun; Ma, Jiao; Li, Aimin

    2018-01-01

    Recently, extrusion press treatment shows some promising advantages for effectively separating of organic fraction of municipal solid waste (OFMSW) from the mixed MSW, which is critical for their following high-efficiency treatment. In this study, an extruded OFMSW obtained from a demonstrated MSW treatment plant was characterized, and submitted to a series of semi-continuous anaerobic experiments to examine its biodegradability and process stability. The results indicated that the extruded OFMSW was a desirable substrate with a high biochemical methane potential (BMP), balanced nutrients and reliable stability. For increasing organic loading rates (OLRs), feeding higher volatile solid (VS) contents in feedstock was much better than shortening the hydraulic retention times (HRTs), while excessively high contents caused a low biodegradability due to the mass transfer limitation. For energetics evaluation, a high electricity output of 129.19-156.37kWh/ton raw MSW was obtained, which was further improved by co-digestion with food waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. 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.

  10. 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.

  11. Regeneration of a deactivated USY alkylation catalyst using supercritical isobutane

    Energy Technology Data Exchange (ETDEWEB)

    Daniel M. Ginosar; David N. Ghompson; Kyle C. Burch

    2005-01-01

    Off-line, in-situ alkylation activity recovery from a completely deactivated solid acid catalyst was examined in a continuous-flow reaction system employing supercritical isobutane. A USY zeolite catalyst was initially deactivated during the liquid phase alkylation of butene with isobutane in a single-pass reactor and then varying amounts of alkylation activity were recovered by passing supercritical isobutane over the catalyst bed at different reactivation conditions. Temperature, pressure and regeneration time were found to play important roles in the supercritical isobutane regeneration process when applied to a completely deactivated USY zeolite alkylation catalyst. Manipulation of the variables that influence solvent strength, diffusivity, surface desorption, hydride transfer rates, and coke aging, strongly influence regeneration effectiveness.

  12. Diffusion Bonding and Post-Weld Heat Treatment of Extruded AZ91 Magnesium Alloys

    Directory of Open Access Journals (Sweden)

    Fei LIN

    2015-11-01

    Full Text Available The grain size of as-extruded AZ91 magnesium alloys was refined to 12.31 μm from 21.41 μm by recrystallization annealing. The vacuum diffusion welding of as-annealed AZ91 magnesium alloys was researched. The results showed that the maximum shear strength of joints reached 64.70 MPa in the situation of 10 MPa bonding pressure, 18 Pa vacuum degree, 470 °C bonding temperature and 90 min bonding time; both bonding temperature and time are the main influence factors on as-extruded AZ91 magnesium alloys diffusion welding. Then the diffusion welded specimens were annealed, and the shear strength of joints was further improved to 76.93 MPa.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9699

  13. Suitability of some promising soot combustion catalysts for application in diesel exhaust treatment

    Energy Technology Data Exchange (ETDEWEB)

    Badini, Claudio; Saracco, Guido; Serra, Valentina; Specchia, Vito [Dipartimento di Scienza dei Materiali ed Ingegneria Chimica, Politecnico di Torino, Corso Duca degli Abruzzi, 24-10129 Torino (Italy)

    1998-09-21

    In this work, the effect of thermal treatment at 380C and 600C, under gaseous atmospheres containing some typical components of diesel emissions (SO{sub 2} and water), was studied on some promising catalysts for diesel particulate combustion. In particular, the ageing behaviour of two novel catalysts (based on CsVO{sub 3}+KCl and KVO{sub 3}+KCl, respectively) and of a more widely studied Cu-K-V-Cl catalyst was investigated. The catalytic activities of these novel catalysts were lower than that of the Cu-K-V-Cl one, but, contrary to this last counterpart, they almost completely maintained their activity during ageing treatments in dry or humid air at 380C and 600C, respectively. Moreover, after prolonged thermal exposure in wet air, the activity of the Cu-K-V-Cl catalyst became comparable with that of the CsVO{sub 3}+KCl one, while remaining still slightly higher than that of the KVO{sub 3}+KCl catalyst. The thermal treatments of all the catalysts under investigation in an atmosphere containing SO{sub 2} did not cause an activity decrease. X-ray diffraction analyses showed the formation of new phases (sulphates and vanadates with a K/V ratio different from that of metavanadates) which could also improve the catalytic activity, counterbalancing the loss of active components due to evaporation at high temperatures. Furthermore, the catalyst activity was evaluated after employing repeatedly these catalysts in carbon combustion. The catalytic activities were generally slightly lowered by the repeated use, even though, from this viewpoint, that of Cu-K-V-Cl was more affected than those of the other catalysts. On the basis of the obtained results the CsVO{sub 3}+KCl catalyst was found to allow the best compromise between satisfactory catalyst activity and stability

  14. Development of extruded Ready-To-Eat (RTE) snacks using corn, black gram, roots and tuber flour blends

    OpenAIRE

    Reddy, M. Kavya; Kuna, Aparna; Devi, N. Lakshmi; Krishnaiah, N.; Kaur, Charanjit; Nagamalleswari, Y.

    2014-01-01

    Extruded RTE snacks were prepared from flour blends made with corn flour, Bengal gram flour, roots and tuber flours in a proportion of 60–80: 20: 20 respectively and moisture was adjusted to 17–20 %. The roots and tubers flours were developed from potato (Solanum tuberosum), yam (Dioscorea spp.), sweet potato (Ipomoea batatas L.), taro (Colocassia esculenta) and beet root (Beta vulgaris). Different formulations were extruded at 80 ± 5 °C (heater I) and 95–105 °C (heater II) temperature, 300–3...

  15. Automotive catalyst strategies for future emission systems

    International Nuclear Information System (INIS)

    Williamson, W.B.; Summers, J.C.; Scaparo, J.A.

    1992-01-01

    This paper reports that while significant advances in Pt/Rh three-way catalyst (TWC) formulations have been accomplished, the use of Pd-containing catalysts for three-way emission control are of interest for overall noble metal cost reduction, lower Rh usage, and potential durability improvements. Applications of Pd are demonstrated for replacement of Pt in conventional Pt/Rh TWC systems, for use in Pd-only three-way catalysts and for lowering methanol and formaldehyde emissions at close-coupled locations on a methanol-fueled vehicle. The individual contributions of Pt, Pd and Rh for aged three-way performance indicate significant advantages of using Pd over Pt. A comparison of vehicle system control strategies illustrates that higher system temperatures significantly lower HC emissions, while air/fuel control strategies are most critical in lowering NO x emissions

  16. Functional properties of plantain, cowpea flours and oat fiber in extruded products

    Science.gov (United States)

    Drying effect on functional properties of two plantain and cowpea varieties and suitability of their flour blends in extruded snacks was determined. The functional and rheological behaviors of (plantain: cowpea): 90:10, 80:20, 70:30, 60:40 and 50:50 blends were evaluated. The extrusion product melt ...

  17. Effect of Hybrid Talc-Basalt Fillers in the Shell Layer on Thermal and Mechanical Performance of Co-Extruded Wood Plastic Composites.

    Science.gov (United States)

    Huang, Runzhou; Mei, Changtong; Xu, Xinwu; Kärki, Timo; Lee, Sunyoung; Wu, Qinglin

    2015-12-08

    Hybrid basalt fiber (BF) and Talc filled high density polyethylene (HDPE) and co-extruded wood-plastic composites (WPCs) with different BF/Talc/HDPE composition levels in the shell were prepared and their mechanical, morphological and thermal properties were characterized. Incorporating BFs into the HDPE-Talc composite substantially enhanced the thermal expansion property, flexural, tensile and dynamic modulus without causing a significant decrease in the tensile and impact strength of the composites. Strain energy estimation suggested positive and better interfacial interactions of HDPE with BFs than that with talc. The co-extruded structure design improved the mechanical properties of WPC due to the protective shell layer. The composite flexural and impact strength properties increased, and the thermal expansion decreased as BF content increased in the hybrid BF/Talc filled shells. The cone calorimetry data demonstrated that flame resistance of co-extruded WPCs was improved with the use of combined fillers in the shell layer, especially with increased loading of BFs. The combined shell filler system with BFs and Talc could offer a balance between cost and performance for co-extruded WPCs.

  18. Preparation and evaluation of enteric coated tablets of hot-melt extruded lansoprazole.

    Science.gov (United States)

    Alsulays, Bader B; Kulkarni, Vijay; Alshehri, Sultan M; Almutairy, Bjad K; Ashour, Eman A; Morott, Joseph T; Alshetaili, Abdullah S; Park, Jun-Bom; Tiwari, Roshan V; Repka, Michael A

    2017-05-01

    The objective of this work was to use hot-melt extrusion (HME) technology to improve the physiochemical properties of lansoprazole (LNS) to prepare stable enteric coated LNS tablets. For the extrusion process, we chose Kollidon ® 12 PF (K12) polymeric matrix. Lutrol ® F 68 was selected as the plasticizer and magnesium oxide (MgO) as the alkalizer. With or without the alkalizer, LNS at 10% drug load was extruded with K12 and F68. LNS changed to the amorphous phase and showed better release compared to that of the pure crystalline drug. Inclusion of MgO improved LNS extrudability and release and resulted in over 80% drug release in the buffer stage. Hot-melt extruded LNS was physically and chemically stable after 12 months of storage. Both formulations were studied for compatibility with Eudragit ® L100-55. The optimized formulation was compressed into a tablet followed by coating process utilizing a pan coater using L100-55 as an enteric coating polymer. In a two-step dissolution study, the release profile of the enteric coated LNS tablets in the acidic stage was less than 10% of the LNS, while that in the buffer stage was more than 80%. Drug content analysis revealed the LNS content to be 97%, indicating the chemical stability of the enteric coated tablet after storage for six months. HME, which has not been previously used for LNS, is a valuable technique to reduce processing time in the manufacture of enteric coated formulations of an acid-sensitive active pharmaceutical ingredient as compared to the existing methods.

  19. An introduction to catalyst

    International Nuclear Information System (INIS)

    Jeon, Hak Je

    1988-11-01

    This book explains basic conception of catalyst such as definition, velocity of chemical reaction and velocity of catalyst reaction, absorption with absorption energy and chemical absorption, pore structure with the role of pore and measurement of pore structure, catalyst activity on solid structure, electrical property on catalyst activity, choice and design of catalyst, catalytic reaction with reaction velocity and chemical equilibrium and reaction velocity model, measurement of reaction velocity and material analysis, catalyst for mixed compound, catalyst for solid acid and catalyst for supported metal.

  20. Application of response surface methodology for studying the product characteristics of extruded rice-cowpea-groundnut blends.

    Science.gov (United States)

    Asare, Emmanuel Kwasi; Sefa-Dedeh, Samuel; Sakyi-Dawson, Esther; Afoakwa, Emmanuel Ohene

    2004-08-01

    Response surface methodology (with central composite rotatable design for k=3) was used to investigate the product properties of extruded rice-cowpea-groundnut blends in a single screw extruder. The combined effect of cowpea (0-20%), groundnut (0-10%), and feed moisture (14-48%) levels were used for formulation of the products. The product moisture, expansion ratio, bulk density and total colour change were studied using standard analytical methods. Well-expanded rice-legume blend extrudates of less bulk density and lower moisture content were produced at low feed moisture. Increasing legume addition affected the various shades of colour in the product. Models developed for the indices gave R(2) values ranging from 52.8% (for the b-value) to 86.5% (for bulk density). The models developed suggested that the optimal process variables for the production of a puffed snack with an enhanced nutrition and spongy structure from a rice-cowpea-groundnut blend are low feed moisture of 14-20% and maximum additions of 20% cowpea and 10% groundnut. A lack-of-fit test showed no significance, indicating that the models adequately fitted the data.

  1. Radical Polymerization of Styrene and Styrene–Butylmethacrylate in a Counterrotating Twin Screw Extruder

    NARCIS (Netherlands)

    Goot, A.J. van der; Janssen, L.P.B.M.

    1997-01-01

    This article describes the copolymerization of styrene–butylmethacrylate (St-BMA) and the homopolymerization of styrene (St) in a counterrotating twin screw extruder. The effect of prepolymerization on both the product properties and process was studied. It turned out that the process of reactive

  2. Radical polymerization of styrene and styrene-butylmethacrylate in a counterrotating twin screw extruder

    NARCIS (Netherlands)

    vanderGoot, AJ; Janssen, LPB

    1997-01-01

    This article describes the copolymerization of styrene-butylmethacrylate (St-BMA) and the homopolymerization of styrene (St) in a counterrotating twin screw extruder. The effect of prepolymerization on both the product properties and process was studied. It turned out that the process of reactive

  3. Effect of Some Extrusion Variables on Rheological Properties and Physicochemical Changes of Cornmeal Extruded by Twin Screw Extruder

    Directory of Open Access Journals (Sweden)

    Chang Y.K.

    1998-01-01

    Full Text Available The effect of extrusion variables, such as barrel temperature (100 to 170ºC, feed rate (100 to 500 g/min, feed moisture (20 to 40 g/100 g wet basis, screw speed rate (from 100 to 500 rpm, and slit die rheometer configuration (0.15 and 0.30 cm height were studied using a co-rotating intermeshing twin-screw extruder coupled to a slit die rheometer on the rheological properties of yellow cornmeal. An increase in feed rate decreased WAI and WSI, but increased the viscosity values. The temperature interacts strongly with screw speed in affecting the WSI. The most important factor in starch degradation was the screw speed. Increasing the screw speed completely modifies the organised structure of starch (crystalline region.

  4. Apically extruded debris in filling removal of curved canals using 3 NiTi systems and hand files.

    Science.gov (United States)

    Delai, Débora; Boijink, Daiana; Hoppe, Carolina Bender; Grecca, Abiana Soares; Kopper, Patrícia Maria Poli

    2018-01-01

    The aim of this study was to assess the amount of apically extruded debris during filling removal with WaveOne Gold (WOG), ProTaper Universal Retreatment (PTR), D-RaCe Retreatment (DRR) or hand files (HF), to compare the working time during filling removal, and to describe failures of NiTi instruments. Forty mesiobuccal roots of maxillary first molars were prepared with WOG Primary, obturated and divided into 4 groups (n=10), according to the instruments used: WOG, PTR, DRR or HF. Distilled water was used as irrigant and the extruded debris were collected in Eppendorf tubes and dried. The amount of extruded debris was determined by subtracting the final from the initial weight. The time of filling removal for each canal was recorded and the instruments used were analyzed pre and post-operatively by SEM. Kruskal-Wallis and Dunn's test analyzed extruded debris data and ANOVA, followed by Tukey's test, compared the working time data (a=0.05). Instrument deformation and fracture were described. WOG produced significantly less debris compared with HF and DRR (p0.05). HF, PTR and DRR showed no significant difference (p>0.05). Working time in HF group was significantly higher than others (p<0.05). SEM analyses showed, from the 18 instruments evaluated, 3 fractures and 10 deformations. All instruments tested caused debris extrusion. WOG was associated with less extrusion than DRR and HF. Filling removal with HF was slower than with the other instruments. All NiTi systems presented fracture and deformation.

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

    Science.gov (United States)

    Amanlou, H; Maheri-Sis, N; Bassiri, S; Mirza-Aghazadeh, A; Salamatdust, R; Moosavi, A; Karimi, V

    2012-01-01

    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 (Pfat. Supplemental fat, whether tallow or full fat soybeans increased milk production (1.89-2.45 kg/d; PMilk fat yield and percentage of cows fed fat-supplemented diets were significantly (Pfat-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 (Pfat 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.

  6. Obtaining low temperature catalysts for methanol synthesis by no-waste process

    Energy Technology Data Exchange (ETDEWEB)

    Il' ko, E G; Sushchaya, L E; Bondar' , P G

    1982-11-01

    Low temperature production of catalysts for methanol synthesis involves considerable pollution of the environment as well as formation of side products. The authors propose producing such catalysts from joint precipitates of copper and zinc carbonates includiing stabilizers produced by decomposing solvents, then drying, aging and shaping. This method avoids waste water usually formed in scrubbing to remove ions of alkaline metals. Aluminum hydroxide is suggested as a stabilizer. The catalyst tablets prepared in this way were found to have activity like those produced by other methods, and were suitable for industrial use.

  7. Catalyst support structure, catalyst including the structure, reactor including a catalyst, and methods of forming same

    Science.gov (United States)

    Van Norman, Staci A.; Aston, Victoria J.; Weimer, Alan W.

    2017-05-09

    Structures, catalysts, and reactors suitable for use for a variety of applications, including gas-to-liquid and coal-to-liquid processes and methods of forming the structures, catalysts, and reactors are disclosed. The catalyst material can be deposited onto an inner wall of a microtubular reactor and/or onto porous tungsten support structures using atomic layer deposition techniques.

  8. 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.

  9. The Evolution of Plate and Extruded Products with High Strength and Fracture Toughness

    Science.gov (United States)

    Denzer, D. K.; Rioja, R. J.; Bray, G. H.; Venema, G. B.; Colvin, E. L.

    From the first use of 2017-T74 on the Junkers F13, improvements have been made to plate and extruded products for applications requiring the highest attainable strength and adequate fracture toughness. One such application is the upper wing of large aircraft. The progression of these product improvements achieved through the development of alloys that include 7075-(T6 & T76), 7150-(T6 & T77) and 7055-(T77 & T79) and most recently 7255-(T77 & T79) is reviewed. The most current advancements include aluminum-copper-lithium, alloy 2055 plate and extruded products that can attain strength equivalent to that of 7055-T77 with higher modulus, similar fracture toughness and improved fatigue, fatigue crack growth and corrosion performance. The achievement of these properties is explained in terms of the several alloy design principles. The highly desired and balanced characteristics make these products ideal for upper wing applications.

  10. Fire resistance of extruded hollow-core slabs

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Giuliani, Luisa; Sørensen, Lars Schiøtt

    2016-01-01

    Prefabricated extruded hollow-core slabs are preferred building components for floor structures in several countries. It is therefore important to be able to document the fire resistance of these slabs proving fulfilment of standard fire resistance requirements of 60- and 120 minutes found in most...... a standard fire test and from a thorough examination of the comprehensive test documentation available on fire exposed hollow-core slabs. Mechanisms for loss of load-bearing capacity are clarified, and evidence of the fire resistance is found. For the first time the mechanisms responsible for loss of load......-bearing capacity are identified and test results and calculation approach are for the first time Applied in accordance with each other for assessment of fire resistance of the structure....

  11. Investigation into mixing capability and solid dispersion preparation using the DSM Xplore Pharma Micro Extruder.

    Science.gov (United States)

    Sakai, Toshiro; Thommes, Markus

    2014-02-01

    The goal of this investigation was to qualify the DSM Xplore Pharma Micro Extruder as a formulation screening tool for early-stage hot-melt extrusion. Dispersive and distributive mixing was investigated using soluplus, copovidone or basic butylated methacrylate copolymer with sodium chloride (NaCl) in a batch size of 5 g. Eleven types of solid dispersions were prepared using various drugs and carriers in batches of 5 g in accordance with the literature. The dispersive mixing was a function of screw speed and recirculation time and the particle size was remarkably reduced after 1 min of processing, regardless of the polymers. An inverse relationship between the particle size and specific mechanical energy (SME) was also found. The SME values were higher than those in large-scale extruders. After 1 min recirculation at 200 rpm, the uniformity of NaCl content met the criteria of the European Pharmacopoeia, indicating that distributive mixing was achieved in this time. For the solid dispersions preparations, the results from different scanning calorimetry, powder X-ray diffractometry and in-vitro dissolution tests confirmed that all solid-dispersion systems were successfully prepared. These findings demonstrated that the extruder is a useful tool to screen solid-dispersion formulations and their material properties on a small scale. © 2013 Royal Pharmaceutical Society.

  12. Bottom-up and Top-down Approaches to Explore Sodium Dodecyl Sulfate and Soluplus on the Crystallization Inhibition and Dissolution of Felodipine Extrudates.

    Science.gov (United States)

    Chen, Jiali; Chen, Yuqi; Huang, Wencong; Wang, Hanning; Du, Yang; Xiong, Subin

    2018-05-05

    The objectives of this study were to explore sodium dodecyl sulfate (SDS) and Soluplus on the crystallization inhibition and dissolution of felodipine (FLDP) extrudates by bottom-up and top-down approaches. FLDP extrudates with Soluplus and/or SDS were prepared by hot melt extrusion (HME), and characterized by PLM, DSC and FT-IR. Results indicated that Soluplus inhibited FLDP crystallization and the whole amorphous solid dispersions (ASDs) were binary FLDP-Soluplus (1:3) and ternary FLDP-Soluplus-SDS(1:2:0.15∼0.3 and 1:3:0.2∼0.4) extrudates. Internal SDS (5%-10%) decreased Tgs of FLDP-Soluplus-SDS ternary ASDs without presenting molecular interactions with FLDP or Soluplus. The enhanced dissolution rate of binary or ternary Soluplus-rich ASDs in the non-sink condition of 0.05%SDS was achieved. Bottom-up approach indicated that Soluplus was a much stronger crystal inhibitor to the supersaturated FLDP in solutions than SDS. Top-down approach demonstrated that SDS enhanced the dissolution of Soluplus-rich ASDs via wettability and complexation with Soluplus to accelerate the medium uptake and erosion kinetics of extrudates, but induced FLDP recrystallization and resulted in incomplete dissolution of FLDP-rich extrudates. In conclusion, top-down approach is a promising strategy to explore the mechanisms of ASDs' dissolution, and small amount of SDS enhances the dissolution rate of polymer-rich ASDs in the non-sink condition. Copyright © 2018. Published by Elsevier Inc.

  13. Characterisation of corn extrudates with the addition of brewers' spent grain as a raw material for the production of functional batters.

    Science.gov (United States)

    Żelaziński, Tomasz; Ekielski, Adam; Siwek, Adam; Dardziński, Leszek

    2017-01-01

    Novel food batters, recommended for various products, are at present manufactured by extru- sion. Thanks to this, it is possible to look for and process new raw materials, if their processing has so far been considered impossible or economically unviable. The purpose of the work was therefore to investigate the extrudates produced from the corn and brewers' spent grain compounds that are subsequently used as raw material for food batter production. The work presents the findings of research on extrusion of corn mixes with varying levels of brewers' spent grains, to the maximum amount of 30%. Tests were conducted using a co-rotating double screw extruder, equipped with a single-outlet matrix with a diameter of 2.5mm. The products obtained were subjected to analysis of their parameters (apparent density, strength parameters, abrasiveness index) and the granulation of a single fraction was checked. The sample for which the percentage content was the highest was subjected to a detailed analysis of particle shape using vision software. It was found that an increase in the content of brewers' spent grains resulted in increased hardness of the products obtained. During the tests it was observed that the increasing hardness of the measured sam- ples is opposite to their abrasion resistance. The maximum decrement of the brasion parameters was seen for extrudates with 30% spent grain addition and was 1.4%, while the minimum decrement values for extrudates with brewers' grain content (10%) amounted to 0.85%. It was noted that this may prove the high brittleness of such products, particularly on the outer surface. It was also observed that lower grindability was recorded for samples produced by extrusion at a temperature of 140°C. On the other hand, higher grindability obtained at a temperature of 120°C may facilitate the grinding of such products, which may be particularly important in the production of food batter. Brewers' spent grains used as an addition to corn groats

  14. Changes in physicochemical properties and in vitro starch digestion of native and extruded maize flours subjected to branching enzyme and maltogenic α-amylase treatment.

    Science.gov (United States)

    Román, Laura; Martínez, Mario M; Rosell, Cristina M; Gómez, Manuel

    2017-08-01

    Extrusion is an increasingly used type of processing which combined with enzymatic action could open extended possibilities for obtaining clean label modified flours. In this study, native and extruded maize flours were modified using branching enzyme (B) and a combination of branching enzyme and maltogenic α-amylase (BMA) in order to modulate their hydrolysis properties. The microstructure, pasting properties, in vitro starch hydrolysis and resistant starch content of the flours were investigated. Whereas BMA treatment led to greater number of holes on the granule surface in native samples, B and BMA extruded samples showed rougher surfaces with cavities. A reduction in the retrogradation trend was observed for B and BMA native flours, in opposition to the flat pasting profile of their extruded counterparts. The glucose release increased gradually for native flours as the time of reaction did, whereas for extruded flours a fast increase of glucose release was observed during the first minutes of reaction, and kept till the end, indicating a greater accessibility to their porous structure. These results suggested that, in enzymatically treated extruded samples, changes produced at larger hierarchical levels in their starch structure could have masked a slowdown in the starch digestion properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. 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.

  16. 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 the Ni...... catalyst. The results from the screening were experimentally verified for CO hydrogenation, CO2 hydrogenation, and simultaneous CO and CO2 hydrogenation by bimetallic Ni-Fe catalysts. These catalysts were found to be highly active and selective. The Co-Ni and Co-Fe systems were investigated for CO...... 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 vanadium-based catalyst...

  17. Temporal analysis of the effect of extruded flaxseed on the swine gut microbiota.

    Science.gov (United States)

    Holman, Devin B; Baurhoo, Bushansingh; Chénier, Martin R

    2014-10-01

    Flaxseed is a rich source of α-linolenic acid, an essential ω-3 fatty acid reported to have beneficial health effects in humans. Feeding swine a diet supplemented with flaxseed has been found to enrich pork products with ω-3 fatty acids. However, the effect of flaxseed supplementation on the swine gut microbiota has not been assessed to date. The purpose of this study was to investigate if extruded flaxseed has any impact on the bacterial and archaeal microbiota in the feces of growing-finishing pigs over a 51-day period, using denaturing gradient gel electrophoresis (DGGE) and real-time PCR. Bacterial DGGE profile analysis revealed major temporal shifts in the bacterial microbiota with only minor ones related to diet. The archaeal microbiota was significantly less diverse than that of Bacteria. The majority of bacterial DGGE bands sequenced belonged to the Firmicutes phylum while the archaeal DGGE bands were found to consist of only 2 species, Methanobrevibacter smithii and Methanosphaera stadtmanae. The abundance of Bacteroidetes decreased significantly from day 0 to day 21 in all diet groups while the abundance of Firmicutes was relatively stable across all diet cohorts and sampling times. There was also no significant correlation between pig mass and the ratio of Firmicutes to Bacteroidetes. While the addition of extruded flaxseed to the feed of growing-finishing pigs was beneficial for improving ω-3 fatty acid content of pork, it had no detectable impact on the fecal bacterial and archaeal microbiota, suggesting that extruded flaxseed may be used to improve meat quality without adverse effect on the swine gut microbiota or animal performance.

  18. Large volume syringe pump extruder for desktop 3D printers

    Directory of Open Access Journals (Sweden)

    Kira Pusch

    2018-04-01

    Full Text Available Syringe pump extruders are required for a wide range of 3D printing applications, including bioprinting, embedded printing, and food printing. However, the mass of the syringe becomes a major challenge for most printing platforms, requiring compromises in speed, resolution and/or volume. To address these issues, we have designed a syringe pump large volume extruder (LVE that is compatible with low-cost, open source 3D printers, and herein demonstrate its performance on a PrintrBot Simple Metal. Key aspects of the LVE include: (1 it is open source and compatible with open source hardware and software, making it inexpensive and widely accessible to the 3D printing community, (2 it utilizes a standard 60 mL syringe as its ink reservoir, effectively increasing print volume of the average bioprinter, (3 it is capable of retraction and high speed movements, and (4 it can print fluids using nozzle diameters as small as 100 μm, enabling the printing of complex shapes/objects when used in conjunction with the freeform reversible embedding of suspended hydrogels (FRESH 3D printing method. Printing performance of the LVE is demonstrated by utilizing alginate as a model biomaterial ink to fabricate parametric CAD models and standard calibration objects. Keywords: Additive manufacturing, 3D bioprinting, Embedded printing, FRESH, Soft materials extrusion

  19. Highly dispersed metal catalyst

    Science.gov (United States)

    Xiao, Xin; West, William L.; Rhodes, William D.

    2016-11-08

    A supported catalyst having an atomic level single atom structure is provided such that substantially all the catalyst is available for catalytic function. A process of forming a single atom catalyst unto a porous catalyst support is also provided.

  20. Diesel Emission Control- Sulfur Effects (DECSE) Program- Phase II Summary Report: NOx Adsorber Catalysts; FINAL

    International Nuclear Information System (INIS)

    None

    2000-01-01

    The investigations performed in this project demonstrated the ability to develop a NO(sub x) regeneration strategy including both an improved lean/rich modulation cycle and rich engine calibration, which resulted in a high NO(sub x) conversion efficiency over a range of operating temperatures. A high-temperature cycle was developed to desulfurize the NO(sub x) absorber catalyst. The effectiveness of the desulfurization process was demonstrated on catalysts aged using two different sulfur level fuels. The major findings of this project are as follows: (1) The improved lean/rich engine calibration achieved as a part of this test project resulted in NO(sub x) conversion efficiencies exceeding 90% over a catalyst inlet operating temperature window of 300 C-450 C. This performance level was achieved while staying within the 4% fuel economy penalty target defined for the regeneration calibration. (2) The desulfurization procedure developed showed that six catalysts, which had been exposed to fuel sulfur levels of 3-, 16-, and 30-ppm for as long as 250 hours, could be recovered to greater than 85% NO(sub x) conversion efficiency over a catalyst inlet operating temperature window of 300 C-450 C, after a single desulfurization event. This performance level was achieved while staying within the 4% fuel economy penalty target defined for the regeneration calibration. (3) The desulfurization procedure developed has the potential to meet in-service engine operating conditions and provide acceptable driveability conditions. (4) Although aging with 78-ppm sulfur fuel reduced NO(sub x) conversion efficiency more than aging with 3-ppm sulfur fuel as a result of sulfur contamination, the desulfurization events restored the conversion efficiency to nearly the same level of performance. However, repeatedly exposing the catalyst to the desulfurization procedure developed in this program caused a continued decline in the catalyst's desulfurized performance. Additional work will be

  1. The Effect of Filler on the Quality of Snack Food Extruded From Solid Matter of Industrial Soybean Tofu

    OpenAIRE

    Salahudin, Farid; Syamsixman, Syamsixman

    2010-01-01

    Tofu filter cake is the waste of tofu processing which is used for animal feed. In the other hand tofu filter cake can be used at extruded food processing. The purpose of this study is to look for the formulas and filler materials which could produce extruded food. The first variable in this research is the kind of corn that is pop corn and maize corn. The second variable is formulas of filler material that is composition of corn: rice: tofu filter cake = 1:1:0.5; 1:1:0.25; 1:2:0.5 and 1:2:0....

  2. Microstructures and mechanical responses of powder metallurgy non-combustive magnesium extruded alloy by rapid solidification process in mass production

    International Nuclear Information System (INIS)

    Kondoh, Katsuyoshi; Hamada, EL-Sayed Ayman; Imai, Hisashi; Umeda, Junko; Jones, Tyrone

    2010-01-01

    Spinning Water Atomization Process (SWAP), which was one of the rapid solidification processes, promised to produce coarse non-combustible magnesium alloy powder with 1-4 mm length, having fine α-Mg grains and Al 2 Ca intermetallic compounds. It had economical and safe benefits in producing coarse Mg alloy powders with very fine microstructures in the mass production process due to its extreme high solidification rate compared to the conventional atomization process. AMX602 (Mg-6%Al-0.5%Mn-2%Ca) powders were compacted at room temperature. Their green compacts with a relative density of about 85% were heated at 573-673 K for 300 s in Ar gas atmosphere, and immediately consolidated by hot extrusion. Microstructure observation and evaluation of mechanical properties of the extruded AMX602 alloys were carried out. The uniform and fine microstructures with grains less than 0.45-0.8 μm via dynamic recrystallization during hot extrusion were observed, and were much small compared to the extruded AMX602 alloy fabricated by using cast ingot. The extremely fine intermetallic compounds 200-500 nm diameter were uniformly distributed in the matrix of powder metallurgy (P/M) extruded alloys. These microstructures caused excellent mechanical properties of the wrought alloys. For example, in the case of AMX602 alloys extruded at 573 K, the tensile strength (TS) of 447 MPa, yield stress (YS) of 425 MPa and 9.6% elongation were obtained.

  3. Effect of coke and catalyst structure on oxidative regeneration of hydroprocessing catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E. (CANMET, Ottawa, ON (Canada). Energy Research Laboratories)

    1991-04-01

    Two industrial hydroprocessing catalysts used for upgrading an atmospheric residue and a gas oil, respectively were regenerated in a fixed bed using air and 2 vol.% O{sub 2}+N{sub 2} balance mixture. The regeneration in air resulted in a significant sintering of the catalyst's material. The surface area of catalysts regenerated in 2 vol.% O{sub 2} mixture was similar to that of fresh catalysts, whereas a significant loss of surface area was observed after regeneration in air. The X-ray diffraction pattern of catalysts regenerated in 2 vol.% O{sub 2}+N{sub 2} balance mixture was also similar to that of fresh catalysts. 22 refs., 9 figs., 7 tabs.

  4. Hydroprocessing catalyst development

    Energy Technology Data Exchange (ETDEWEB)

    Boorman, P.M.; Kydd, R.A.; Sorensen, T.S.; Chong, K.; Lewis, J.

    1992-08-01

    Co-Mo and Ni-Mo hydroprocessing catalysts were examined for their activity in removal of sulfur from thiophene in model compounds, and in the cracking and hydrocracking of cumene. Three types of support materials were examined: carbon, modified carbon, and carbon covered alumina. The objective of the study was to examine the correlation between catalyst activity in the hydrodenitrogenation of model compounds, and the resistance of the catalyst to nitrogen poisoning during use in the hydroprocessing of gas oils. The use of model compound testing provided information on the individual catalytic reactions promoted by those materials. Infrared spectroscopy was used to study surface species on the catalysts and to explain many of the trends in activity observed, revealing the role of fluoride and phosphorus as a secondary promoter. Testing of the catalysts in hydrotreating of gas oils allowed comparison of model compound results with those from a real feedstock. The gas oil was also spiked with a model nitrogen compound and the results from catalytic hydrotreating of this material were compared with those from unspiked material. A key finding was that the carbon supported catalysts were the most effective in treating high-nitrogen feeds. The very favorable deactivation properties of carbon and carbon-covered alumina supported catalysts make these promising from an industrial point of view where catalyst deactivation is a limiting factor. 171 refs., 25 figs., 43 tabs.

  5. In-situ analysis of the slip activity during tensile deformation of cast and extruded Mg-10Gd-3Y-0.5Zr (wt.%) at 250 °C

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H. [National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); The State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824 (United States); Boehlert, C.J., E-mail: boehlert@egr.msu.edu [Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824 (United States); Wang, Q.D., E-mail: wangqudong@sjtu.edu.cn [National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); The State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); Yin, D.D. [Key Laboratory of Advanced Materials Technology under Ministry of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Ding, W.J. [National Engineering Research Center of Light Alloy Net Forming, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China); The State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240 (China)

    2016-06-15

    The slip activity and slip interaction in tensile deformation of peak-aged cast and extruded Mg-10Gd-3Y-0.5Zr (wt.%) at 250 °C was investigated using in-situ scanning electron microscopy. Basal slip was the most likely system to be activated during the tensile deformation, while prismatic < a > and pyramidal < c + a > slip also contributed to the deformation. No twinning was observed. The number of non-basal slip systems accounted for ~ 36% of the total active slip systems for the cast alloy, while non-basal slip accounted for 12–17% of the total deformation observations in the extruded alloy. Multiple-slip was observed within grains, and the basal/prismatic pairing type dominated the multiple-slip observations. Slip transfer occurred across grain boundaries and most of the slip transfer observations showed basal-basal type. The involved slip systems of slip transfer pairs were always associated with the same < a > direction. The slip transfer occurred more easily at low angle boundaries (LABs) and boundaries with misorientations greater than 75°. - Highlights: • Slip deformation of a Mg-RE alloy at 250 °C was investigated using in-situ SEM. • The extruded-T5 GW103 alloy did not exhibit a high anisotropic behavior. • Multiple-slip was observed within grains, and basal/prismatic type dominated. • Slip transfer occurred and most of the observations showed basal-basal type. • Slip transfer occurred more easily at LABs and boundaries with misorientations > 75°.

  6. Determination of surface energies of hot-melt extruded sugar-starch pellets.

    Science.gov (United States)

    Yeung, Chi-Wah; Rein, Hubert

    2018-02-01

    Hot-melt extruded sugar-starch pellets are an alternative for commercial sugar spheres, but their coating properties remain to be studied. Both the European Pharmcopoeia 8.6 and the United States Pharmacopoeia 40 specify the composition of sugar-starch pellets without giving requirements for the manufacturing process. Due to various fabrication techniques, the physicochemical properties of pellets may differ. Therefore, the adhesion energies of three coating dispersions (sustained, enteric and immediate release) on different types of pellets were investigated. In this context, the surface energies of various kinds of corn starch (normal, waxy, high-amylose) and sucrose pellets were analyzed using the sessile drop method, whereas the surface tensions of the coating dispersions were examined using the pendant drop method. The adhesion forces were calculated from the results of these studies. Furthermore, sugar spheres were characterized in terms of particle size distribution, porosity and specific surface area. An increase of the pellets' sucrose content leads to a more porous surface structure, which gives them an enhanced wetting behavior with coating dispersions. The adhesion energies of extruded sugar-starch pellets are similar to those of commercial sugar spheres, which comply with pharmacopeial requirements. Both types of pellets are equally suited for coating.

  7. 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.

  8. Production and quality evaluation of extruded snack from blends of bambara groundnut flour, cassava starch, and corn bran flour

    OpenAIRE

    Ogunmuyiwa, O. H.; Adebowale, A. A.; Sobukola, O. P.; Onabanjo, O. O.; Obadina, A. O.; Adegunwa, M. O.; Kajihausa, O. E.; Sanni, L. O.; Tomlins, Keith

    2017-01-01

    Protein dense, fiber-rich extruded snacks were produced from blend of bambara groundnut flour, cassava starch, and corn bran flour using a single screw cooking extruder. The snacks were analyzed for their physical properties and proximate composition using standard laboratory procedures. The expansion ratio, specific volume, breaking force, and breaking strength index (BSI) of the snacks ranged from 0.85 to 1.22, 0.75 to 1.30 g/cm3, 3.95 to 36.45 N, and 0.99 to 9.11 N/mm, respectively. The br...

  9. Single screw extrusion of apple pomace-enriched blends: Extrudate characteristics and determination of optimum processing conditions.

    Science.gov (United States)

    Singha, Poonam; Muthukumarappan, Kasiviswanathan

    2018-07-01

    Response surface methodology was used to investigate the single screw extrusion of apple pomace-defatted soy flour-corn grits blends and the product properties. Five different blends at a level of 0-20% w/w apple pomace were extrusion cooked with varied barrel and die temperature (100-140℃), screw speed (100-200 rpm), and feed moisture content (14-20% wet basis). Increasing apple pomace content in the blends significantly ( P extrudates. The expansion ratio increased with pomace inclusion level of 5% but decreased significantly ( P extruded snack products were at 140℃ barrel and die temperature, 20% feed moisture content, and 200 rpm screw speed. The results indicated active interaction between apple pomace and starch during expansion process.

  10. Supported catalyst systems and method of making biodiesel products using such catalysts

    Science.gov (United States)

    Kim, Manhoe; Yan, Shuli; Salley, Steven O.; Ng, K. Y. Simon

    2015-10-20

    A heterogeneous catalyst system, a method of preparing the catalyst system and a method of forming a biodiesel product via transesterification reactions using the catalyst system is disclosed. The catalyst system according to one aspect of the present disclosure represents a class of supported mixed metal oxides that include at least calcium oxide and another metal oxide deposited on a lanthanum oxide or cerium oxide support. Preferably, the catalysts include CaO--CeO.sub.2ZLa.sub.2O.sub.3 or CaO--La.sub.2O.sub.3/CeO.sub.2. Optionally, the catalyst may further include additional metal oxides, such as CaO--La.sub.2O.sub.3--GdOxZLa.sub.2O.sub.3.

  11. Assessment of apically extruded debris produced by the self-adjusting file system.

    Science.gov (United States)

    De-Deus, Gustavo André; Nogueira Leal Silva, Emmanuel João; Moreira, Edson Jorge; de Almeida Neves, Aline; Belladonna, Felipe Gonçalves; Tameirão, Michele

    2014-04-01

    This study was designed to quantitatively evaluate the amount of apically extruded debris by the Self-Adjusting-File system (SAF; ReDent-Nova, Ra'anana, Israel). Hand and rotary instruments were used as references for comparison. Sixty mesial roots of mandibular molars were randomly assigned to 3 groups (n = 20). The root canals were instrumented with hand files using a crown-down technique. The ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) and SAF systems were used according to the manufacturers' instructions. Sodium hypochlorite was used as an irrigant, and the apically extruded debris was collected in preweighted glass vials and dried afterward. The mean weight of debris was assessed with a microbalance and statistically analyzed using 1-way analysis of variance and the post hoc Tukey multiple comparison test. Hand file instrumentation produced significantly more debris compared with the ProTaper and SAF systems (P system produced significantly more debris compared with the SAF system (P systems caused apical debris extrusion. SAF instrumentation was associated with less debris extrusion compared with the use of hand and rotary files. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Investigation of functional properties and color changes of corn extrudates enriched with broccoli or olive paste.

    Science.gov (United States)

    Bisharat, Ghassan I; Katsavou, Ioanna D; Panagiotou, Nikolaos M; Krokida, Magdalini K; Maroulis, Zacharias B

    2015-12-01

    Following the tendency of replacing common food snacks with healthier food products, extruded snacks with corn flour and broccoli (4-10%) or olive paste (4-8%) were investigated in this study. The effect of material characteristics, including feed moisture content (14-19%), and broccoli or olive paste concentration, and extrusion conditions, including screw speed (150-250 r/min), and extrusion temperature (140-180 ℃), on the functional properties (water absorption index, water solubility index, and oil absorption index), as well as color change (ΔE) of the extruded snacks was studied. Regression analysis showed that screw speed did not significantly influence (p > 0.05) the properties. After mathematical modelling it was found that broccoli and olive paste concentration, as well as temperature increment, caused a decrease in water absorption index (minimum of 5.6 and 6.4 g/g sample, respectively) and an increase in water solubility index (maximum of 18.7 and 10.9 g/100 g sample, respectively), while feed moisture presented opposite tendency. Higher extrusion temperature led to an increment of oil absorption index (approximately to 1.2 and 1 mL/g sample) and decrement of color changes. Finally, feed moisture and broccoli concentration lowered oil absorption index and color of corn/broccoli extrudates, while olive paste concentration caused their increment. © The Author(s) 2014.

  13. The influence of feed supplementation with linseed oil and linseed extrudate on fatty acid profile in goat yoghurt drinks

    Directory of Open Access Journals (Sweden)

    Markéta Borková

    2018-01-01

    Full Text Available Feed composition is one of the most influential factors affecting fatty acid profile of milk products. The aim of this study was to investigate the influence of linseed oil and linseed extrudate supplementation on fatty acid composition of goat prebiotic and probiotic yogurt drinks. Thirty six White Shorthaired dairy goats at the beginning of their third lactation period were divided into two experimental and one control group, each comprising twelve animals. Goats in the experimental groups were given either 55 mL/day of linseed oil or 120 g/day of linseed extrudate over a three week period. The results suggest that feed supplementation with linseed oil and linseed extrudate caused considerable changes in fatty acid profile of goat yoghurt drinks. The most important nutritional change which was observed was increased n-3 fatty acid content (P<0.001 and decreased saturated fatty acid content (P<0.001. α-linolenic acid was significantly elevated (P<0.001 in both groups (in particular in goats which feed was supplemented with linseed oil.

  14. Tailored sPP/Silica Nano composite for Eco friendly Insulation of Extruded HVDC Cable

    International Nuclear Information System (INIS)

    Dang, B.; He, J.; Hu, J.; Zhou, Y.

    2015-01-01

    Cross-linked polyethylene (XLPE) is a thermosetting material that cannot be recycled at the end of its lifetime. This study investigated the potential of syndiotactic polypropylene (sPP)/silica as an eco friendly extruded insulation system for HVDC cables. We investigated the morphology, Fourier transform infrared, and thermal, thermomechanical, and electrical behaviors of sPP modified with 0.5-3% nano silica. We found that the silica/sPP nano composite without cross-linking offered a suitable mechanical modulus at room temperature and sufficient intensity at high temperatures, and adding nano silica modified by a silane coupling agent to the sPP resulted in significant DC resistivity and space charge improvement. The optimal nano silica content in the sPP was determined by balancing the mechanical and thermomechanical characteristics and the DC resistivity. The sPP/silica nano composite reported here shows great potential as a candidate insulation material for future eco friendly extruded HVDC cables.

  15. Enhanced hydrothermal stability of Cu-ZSM-5 catalyst via surface modification in the selective catalytic reduction of NO with NH_3

    International Nuclear Information System (INIS)

    Zhang, Tao; Shi, Juan; Liu, Jian; Wang, Daxi; Zhao, Zhen; Cheng, Kai; Li, Jianmei

    2016-01-01

    Highlights: • The hydrothermal stability of Cu-ZSM-5 catalyst was enhanced after surface modification. • An inert silica layer was deposited on the surface of Cu-ZSM-5 and formed a protective layer. • The contact between Si and Cu and Al atoms could form Si-O-Al and Si- O−Cu bonds. • The redox and acidity properties of Cu-ZSM-5-CLD-Aged catalyst were largely retained. • The adsorption and activation of NO and NH_3 was almost unchanged over Cu-ZSM-5-CLD catalyst before and after hydrothermal treatment. - Abstract: The surface of Cu-ZSM-5 catalyst was modified by chemical liquid deposition (CLD) of tetraethoxysilane (TEOS) for enhancing its hydrothermal stability in the selective catalytic reduction of NO with NH_3. After hydrothermal aging at 750 °C for 13 h, the catalytic performance of Cu-ZSM-5-Aged catalyst was significantly reduced for NO reduction in the entire temperature range, while that of Cu-ZSM-5-CLD-Aged catalyst was affected very little. The characterization results indicated that an inert silica layer was deposited on the surface of Cu-ZSM-5 and formed a protective layer, which prevents the detachment of Cu"2"+ from ZSM-5 ion-exchange positions and the dealumination of zeolite during the hydrothermal aging process. Based on the data it is hypothesized to be the primary reason for the high hydrothermal stability of Cu-ZSM-5-CLD catalyst.

  16. Controlling the extrudate swell in melt extrusion additive manufacturing of 3D scaffolds: a designed experiment.

    Science.gov (United States)

    Yousefi, Azizeh-Mitra; Smucker, Byran; Naber, Alex; Wyrick, Cara; Shaw, Charles; Bennett, Katelyn; Szekely, Sarah; Focke, Carlie; Wood, Katherine A

    2018-02-01

    Tissue engineering using three-dimensional porous scaffolds has shown promise for the restoration of normal function in injured and diseased tissues and organs. Rigorous control over scaffold architecture in melt extrusion additive manufacturing is highly restricted mainly due to pronounced variations in the deposited strand diameter upon any variations in process conditions and polymer viscoelasticity. We have designed an I-optimal, split-plot experiment to study the extrudate swell in melt extrusion additive manufacturing and to control the scaffold architecture. The designed experiment was used to generate data to relate three responses (swell, density, and modulus) to a set of controllable factors (plotting needle diameter, temperature, pressure, and the dispensing speed). The fitted regression relationships were used to optimize the three responses simultaneously. The swell response was constrained to be close to 1 while maximizing the modulus and minimizing the density. Constraining the extrudate swell to 1 generates design-driven scaffolds, with strand diameters equal to the plotting needle diameter, and allows a greater control over scaffold pore size. Hence, the modulus of the scaffolds can be fully controlled by adjusting the in-plane distance between the deposited strands. To the extent of the model's validity, we can eliminate the effect of extrudate swell in designing these scaffolds, while targeting a range of porosity and modulus appropriate for bone tissue engineering. The result of this optimization was a predicted modulus of 14 MPa and a predicted density of 0.29 g/cm 3 (porosity ≈ 75%) using polycaprolactone as scaffold material. These predicted responses corresponded to factor levels of 0.6 μm for the plotting needle diameter, plotting pressure of 2.5 bar, melt temperature of 113.5 °C, and dispensing speed of 2 mm/s. The validation scaffold enabled us to quantify the percentage difference for the predictions, which was 9.5% for the

  17. 'The effect of inulin addition on structural and textural properties of extruded products under several extrusion conditions': The effect of inulin addition on structural and textural properties of rice flour extrudates.

    Science.gov (United States)

    Tsokolar-Tsikopoulos, Konstantinos C; Katsavou, Ioanna D; Krokida, Magdalini K

    2015-10-01

    The growing consumer demand for healthy snacks has turned the interest of industry and research in the development of new ready-to-eat products, enriched with dietary fibers. Inulin is a soluble fiber with a neutral taste that promotes the good function of the intestine. Rice flour extrudates were produced under various extrusion temperatures, screw speeds, feed moisture concentrations and inulin replacement levels. The objective of this study was to investigate the effect of the material characteristics and the extrusion conditions on the structural and textural properties of the extrudates. Simple mathematical models were used for properties correlation with process conditions and through regression analysis it was revealed that there is a significant effect of extrusion temperature, screw speed, feed moisture content and inulin concentration on the final properties. Both density and maximum stress increased when moisture content and inulin concentration increased, while they decreased when extrusion temperature and screw speed increased. These results were also strengthened by scanning electron microscopy. The highest expansion ratio was presented when decreasing all process conditions apart from screw speed.

  18. Extruded snacks from whole wheat supplemented with textured soy flour: Effect on instrumental and sensory textural characteristics.

    Science.gov (United States)

    Rodríguez-Vidal, Arturo; Martínez-Flores, Héctor Eduardo; González Jasso, Eva; Velázquez de la Cruz, Gonzalo; Ramírez-Jiménez, Aurea K; Morales-Sánchez, Eduardo

    2017-06-01

    The quality of extruded snacks can be affected not only by processing conditions, but also by some factors like the concentration and type of ingredients incorporated in their formulation and the working conditions used. Although the process conditions have been established with measurable textural properties, sensory qualities have not been correlated with these responses in expanded extruded snacks made with added functional ingredients. Therefore, in this study the effect of adding textured soy flour (TSF) and whole wheat flour (WWF) to refined wheat flour in the production of extruded snacks and expanded with hot air was evaluated. A response surface design using two levels with five central points was applied to obtain the best combinations of functional ingredients added, holding the parameters of the extrusion process and moisture of treatments. Some texture characteristics and sensory analysis were used as response variables, such as, hardness, fracturability, toughness, crispness, granularity, and chewiness. Likewise, the rate of expansion was evaluated. The results showed that the level of substitution of WWF, especially levels of 15%, had a significant effect on the hardness perceived by the panelist during sensory evaluation. The TSF at concentrations of ≥15%, favored the fracturability and crispness of the samples. It was found that the best expansion index was with the combination of 5% TSF and 15% WWF. Although a correlation between instrumental and sensory tests carried out on the extruded snacks expanded was not found. The physical characteristics of the extruded snacks such as expansion, hardness, and density are important parameters in terms of consumer acceptability of the final product as well as their functional properties. In other words, the appearance and texture are two of the most important attributes that can be seen in snack foods. In particular, the texture can be measured by intrinsic tests: objective (instrumental) and subjective

  19. Evaluating the NOx Storage Catalysts (NSC Aging: A Preliminary Analytical Study with Electronic Microscopy

    Directory of Open Access Journals (Sweden)

    Leonarda Bellebuono

    2017-10-01

    Full Text Available This paper describes an expeditious and reliable method for determining the thermal effects in a static condition of commercial NOx storage catalysts (NSCs using scanning electron microscopy with an energy dispersive X-ray analytical system (SEM/EDS. It is worth remarking that possible changes in the morphology and in the elemental composition of the catalyst may be considered as the most important causes of the lower conversion of NOx. The information attained in this work indicates that Pt nanoparticle sintering is strongly increased by the oxygen exposure, and this can be considered a very useful preliminary investigation for the studies already present in the literature on the efficiency of NSCs.

  20. High-Activity Dealloyed Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Kongkanand, Anusorn [General Motors LLC, Pontiac, MI (United States)

    2014-09-30

    Reduction of costly Pt usage in proton exchange membrane fuel cell electrodes is one of the major challenges towards development and commercialization of fuel cell vehicles. Although few have met the initial-kinetic activity requirements in a realistic fuel cell device, no catalyst material has ever met the demanding fuel cell durability targets set by DOE. In this project, a team of 4 universities and 2 companies came together to investigate a concept that appeared promising in preliminary non-fuel cell tests then to further develop the catalyst to a mature level ready for vehicle implementation. The team consists of academia with technical leadership in their respective areas, a catalyst supplier, and a fuel cell system integrator.The tightly collaborative project enabled development of a highly active and durable catalyst with performance that significantly exceeds that of previous catalysts and meets the DOE targets for the first time (Figure 1A). The catalyst was then further evaluated in full-active-area stack in a realistic vehicle operating condition (Figure 1B). This is the first public demonstration that one can realize the performance benefit and Pt cost reduction over a conventional pure Pt catalyst in a long-term realistic PEMFC system. Furthermore, systematic analyses of a range of catalysts with different performance after fuel cell testing allowed for correlation between catalyst microstructure and its electrocatalytic activity and durability. This will in turn aid future catalyst development.

  1. Numerical studies of the polymer melt flow in the extruder screw channel and the forming tool

    Science.gov (United States)

    Ershov, S. V.; Trufanova, N. M.

    2017-06-01

    To date, polymer compositions based on polyethylene or PVC is widely used as insulating materials. These materials processing conjugate with a number of problems during selection of the rational extrusion regimes. To minimize the time and cost when determining the technological regime uses mathematical modeling techniques. The paper discusses heat and mass transfer processes in the extruder screw channel, output adapter and the cable head. During the study were determined coefficients for three rheological models based on obtained viscosity vs. shear rate experimental data. Also a comparative analysis of this viscosimetric laws application possibility for studying polymer melt flow during its processing on the extrusion equipment was held. As a result of numerical study the temperature, viscosity and shear rate fields in the extruder screw channel and forming tool were obtained.

  2. Evaluation of apically extruded debris during root canal retreatment with two different rotary systems followed by a self-adjusting file.

    Science.gov (United States)

    Cakici, Fatih; Cakici, Elif B; Küçükekenci, Funda Fundaoglu

    2016-02-01

    To compare the amount of apically extruded debris during root canal retreatment using ProTaper retreatment system (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper retreatment system with Self-Adjusting File (SAF) system (ReDent-Nova, Ra'anana, Israel), Mtwo retreatment system (VDW, Munich, Germany), Mtwo retreatment system with SAF instruments. In total, 72 extracted human mandibular incisor teeth were used. All root canals were prepared with ProTaper universal (Dentsply Maillefer) up to F2 file and filled with gutta percha and AH plus sealer using cold lateral condensation before being assembled randomly into 4 groups (n = 18 each). Root canal filling materials were removed using the ProTaper retreatment system, the ProTaper retreatment system followed by SAF system, Mtwo retreatment system and Mtwo retreatment system followed by SAF system. Debris extruded apically during the removal of canal filling material was collected into preweighed Eppendorf tubes. The tubes were then stored in an incubator at 70°C for 5 days. The weight of the dry extruded debris was established by subtracting the preretreatment and postretreatment weight of the Eppendorf tubes for each group. The data obtained were analyzed using Kruskal-Wallis test. All retreatment techniques caused the apical extrusion of debris. There was no significant difference between the groups statistically (p>0.05). The results of this study showed that SAF system after Mtwo retreatment system and ProTaper retreatment system for improving retreatment has no significant effect on the amount of debris extruded apically.

  3. Investigation of process and product parameters for physicochemical properties of rice and mung bean (Vigna radiata) flour based extruded snacks.

    Science.gov (United States)

    Sharma, Chetan; Singh, Baljit; Hussain, Syed Zameer; Sharma, Savita

    2017-05-01

    PR 106 and SML 668 cultivars of rice and mung bean respectively, were studied for their potential to serve as a nutritious snack with improved protein quality and quantity. The effect of extrusion conditions, including feed moisture content (14-18%), screw speed (400-550 rpm) and barrel temperature (130-170°C) on the physicochemical properties (bulk density, water absorption index (WAI), water solubility index (WSI) and hardness) was investigated. The replacement of rice flour at 30% level with mung bean flour for making extruded snacks was evaluated. Pasting temperature increased (84-93 °C) while peak viscosity (2768-408 cP), hold viscosity (2018-369 cP), breakdown (750-39 cP), setback (2697-622 cP) and final viscosity (4715-991 cP) decreased with increasing mung bean flour addition. Increasing feed moisture lowered the specific mechanical energy (SME), WAI and WSI of extrudates whereas increased bulk density and hardness. Higher screw speed had linear positive effect on SME of extruder and negative linear effect on WAI. Positive curvilinear quadratic effect of screw speed was also observed on WSI and density. Higher barrel temperature linearly decreased the SME, density and hardness of extrudates. Developed extrusion cooked rice-mung bean snacks with increased protein content and improved protein quality along with higher dietary fibre and minerals have good potential in effectively delivering the nutrition to the population.

  4. A comparison of the mechanical and sensory properties of baked and extruded confectionery products

    Science.gov (United States)

    Butt, Saba; Charalambides, Maria; Mohammed, Idris K.; Powell, Hugh

    2017-10-01

    Traditional baking is the most common way of producing confectionery wafers, however over the past few decades, the extrusion process has become an increasingly important food manufacturing method and is commonly used in the manufacturing of breakfast cereals and filled snack products. This study aims to characterise products made via each of these manufacturing processes in order to understand the important parameters involved in the resulting texture of confectionery products such as wafers. Both of the named processes result in brittle, cellular foams comprising of cell walls and cell pores which may contain some of the confectionery filling. The mechanical response of the cell wall material and the geometry of the products influence the consumer perception and preference. X-Ray micro tomography (XRT) was used to generate geometry of the microstructure which was then fed to Finite Element (FE) for numerical analysis on both products. The FE models were used to determine properties such as solid modulus of the cell walls, Young's modulus of the entire foam and to investigate and compare the microstructural damage of baked wafers and extruded products. A sensory analysis study was performed on both products by a qualified sensory panel. The results of this study were then used to draw links between the mechanical behaviour and sensory perception of a consumer. The extruded product was found to be made up of a stiffer solid material and had a higher compressive modulus and fracture stress when compared to the baked wafer. The sensory panel observed textural differences between the baked and extruded products which were also found in the differences of the mechanical properties of the two products.

  5. Development of Molecular Catalysts to Bridge the Gap between Heterogeneous and Homogeneous Catalysts

    Science.gov (United States)

    Ye, Rong

    Catalysts, heterogeneous, homogeneous, and enzymatic, are comprised of nanometer-sized inorganic and/or organic components. They share molecular factors including charge, coordination, interatomic distance, bonding, and orientation of catalytically active atoms. By controlling the governing catalytic components and molecular factors, catalytic processes of a multichannel and multiproduct nature could be run in all three catalytic platforms to create unique end-products. Unifying the fields of catalysis is the key to achieving the goal of 100% selectivity in catalysis. Recyclable catalysts, especially those that display selective reactivity, are vital for the development of sustainable chemical processes. Among available catalyst platforms, heterogeneous catalysts are particularly well-disposed toward separation from the reaction mixture via filtration methods, which renders them readily recyclable. Furthermore, heterogeneous catalysts offer numerous handles - some without homogeneous analogues - for performance and selectivity optimization. These handles include nanoparticle size, pore profile of porous supports, surface ligands and interface with oxide supports, and flow rate through a solid catalyst bed. Despite these available handles, however, conventional heterogeneous catalysts are themselves often structurally heterogeneous compared to homogeneous catalysts, which complicates efforts to optimize and expand the scope of their reactivity and selectivity. Ongoing efforts are aimed to address the above challenge by heterogenizing homogeneous catalysts, which can be defined as the modification of homogeneous catalysts to render them in a separable (solid) phase from the starting materials and products. Specifically, we grow the small nanoclusters in dendrimers, a class of uniform polymers with the connectivity of fractal trees and generally radial symmetry. Thanks to their dense multivalency, shape persistence and structural uniformity, dendrimers have proven to

  6. Communicating catalysts

    Science.gov (United States)

    Weckhuysen, Bert M.

    2018-06-01

    The beauty and activity of enzymes inspire chemists to tailor new and better non-biological catalysts. Now, a study reveals that the active sites within heterogeneous catalysts actively cooperate in a fashion phenomenologically similar to, but mechanistically distinct, from enzymes.

  7. Fire resistance of extruded hollow-core slabs

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Sørensen, Lars Schiøtt; Giuliani, Luisa

    2017-01-01

    to the structural codes with data derived from a standard fire test and from a thorough examination of the comprehensive test documentation available on fire exposed hollow-core slabs. Findings – Mechanisms for loss of load-bearing capacity are clarified, and evidence of the fire resistance is found. Originality......Purpose – Prefabricated extruded hollow-core slabs are preferred building components for floor structures in several countries. It is therefore important to be able to document the fire resistance of these slabs proving fulfilment of standard fire resistance requirements of 60 and 120 min found...... in most national building regulations. The paper aims to present a detailed analysis of the mechanisms responsible for the loss of loadbearing capacity of hollow-core slabs when exposed to fire. Design/methodology/approach – Furthermore, it compares theoretica calculation and assessment according...

  8. Methods of making textured catalysts

    Science.gov (United States)

    Werpy, Todd [West Richland, WA; Frye, Jr., John G.; Wang, Yong [Richland, WA; Zacher, Alan H [Kennewick, WA

    2010-08-17

    A textured catalyst having a hydrothermally-stable support, a metal oxide and a catalyst component is described. Methods of conducting aqueous phase reactions that are catalyzed by a textured catalyst are also described. The invention also provides methods of making textured catalysts and methods of making chemical products using a textured catalyst.

  9. In-situ hydrodeoxygenation of phenol by supported Ni catalyst-explanation for catalyst performance

    DEFF Research Database (Denmark)

    Wang, Ze; Zeng, Ying; Lin, Weigang

    2017-01-01

    In-situ hydrodeoxygenation of phenol with aqueous hydrogen donor over supported Ni catalyst was investigated. The supported Ni catalysts exerted very poor performance, if formic acid was used as the hydrogen donor. Catalyst modification by loading K, Na, Mg or La salt could not make the catalyst...... performance improved. If gaseous hydrogen was used as the hydrogen source the activity of Ni/Al2O3 was pretty high. CO2 was found poisonous to the catalysis, due to the competitive adoption of phenol with CO2. If formic acid was replaced by methanol, the catalyst performance improved remarkably, with major...... products of cyclohexanone and cyclohexanol. The better effect of methanol enlightened the application of the supported Ni catalyst in in-situ hydrodeoxygenation of phenol....

  10. Non-PGM cell catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Colon-Mercado, H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Elvington, M. [Savannah River Consulting, Aiken, SC (United States); Ganesan, P. [Savannah River Consulting, Aiken, SC (United States)

    2017-09-27

    A unique approach has been developed to probe the non-PGM catalyst active site for the Oxygen Reduction Reaction (ORR) for PEMFCs. Iron based functionalities have been engineered into a variety of catalysts to evaluate their impact on activity for the ORR. A series of high surface area catalysts were synthesized and the impact of the chemical structure on the electrochemical and electrocatalytic properties was investigated. Elemental and surface analyses of the prepared catalysts reveal the incorporation of iron in a targeted and controlled manner. A high surface area framework catalyst was prepared that shows exceptional activity, comparable to state-of-the-art materials. The results of this research project provided critical seed data for the newly awarded ElectroCat project, which focuses on rationally designed framework catalysts for the oxygen reduction reaction.

  11. Enhanced hydrothermal stability of Cu-ZSM-5 catalyst via surface modification in the selective catalytic reduction of NO with NH{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Tao; Shi, Juan; Liu, Jian, E-mail: liujian@cup.edu.cn; Wang, Daxi; Zhao, Zhen, E-mail: zhenzhao@cup.edu.cn; Cheng, Kai; Li, Jianmei

    2016-07-01

    Highlights: • The hydrothermal stability of Cu-ZSM-5 catalyst was enhanced after surface modification. • An inert silica layer was deposited on the surface of Cu-ZSM-5 and formed a protective layer. • The contact between Si and Cu and Al atoms could form Si-O-Al and Si- O−Cu bonds. • The redox and acidity properties of Cu-ZSM-5-CLD-Aged catalyst were largely retained. • The adsorption and activation of NO and NH{sub 3} was almost unchanged over Cu-ZSM-5-CLD catalyst before and after hydrothermal treatment. - Abstract: The surface of Cu-ZSM-5 catalyst was modified by chemical liquid deposition (CLD) of tetraethoxysilane (TEOS) for enhancing its hydrothermal stability in the selective catalytic reduction of NO with NH{sub 3}. After hydrothermal aging at 750 °C for 13 h, the catalytic performance of Cu-ZSM-5-Aged catalyst was significantly reduced for NO reduction in the entire temperature range, while that of Cu-ZSM-5-CLD-Aged catalyst was affected very little. The characterization results indicated that an inert silica layer was deposited on the surface of Cu-ZSM-5 and formed a protective layer, which prevents the detachment of Cu{sup 2+} from ZSM-5 ion-exchange positions and the dealumination of zeolite during the hydrothermal aging process. Based on the data it is hypothesized to be the primary reason for the high hydrothermal stability of Cu-ZSM-5-CLD catalyst.

  12. 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...... of the novel catalyst material for synthesising hydrogen peroxide from oxygen and hydrogen, or from oxygen and water....

  13. The measurement of density distribution of bentonite buffer extruded into fractures

    International Nuclear Information System (INIS)

    Matsumoto, Kazuhiro; Tanai, Kenji

    2008-01-01

    For the geological disposal of the high-level radioactive waste, it is important to develop the model to evaluate the long-term stability of the engineered barrier system. The increase in the reliability of the evaluation model may reduce the uncertainty of the safety assessment. In this study, the density distribution of the bentonite buffer extruded into the artificial fractures was measured by using a X-ray CT scanner to promote understanding of the extrusion phenomenon of the bentonite into fractures. (author)

  14. Vibration measurements of automobile catalyst

    Science.gov (United States)

    Aatola, Seppo

    1994-09-01

    Vibration of catalyst cell, which is inside the casing of the catalyst, is difficult to measure with usual measuring instrumentation. When catalyst is in use, there is hot exhaust gas flow though the catalyst cell and temperature of the cell is approximately +900 degree(s)C. Therefore non-contact Laser- Doppler-Vibrometer was used to measure vibration velocity of the catalyst cell. The laser beam was directed towards the cell through pipe which was put through and welded to the casing of the catalyst. The outer end of the pipe was screw down with a tempered class to prevent exhaust gas flow from the pipe. The inner end of the pipe was open and few millimeters away from the measuring point. Catalyst was attached to the engine with two ways, rigidly close to the engine and flexible under the engine. The engine was running in test bench under controlled conditions. Vibration measurements were carried out during constant running speeds of the engine. Vibration signals were captured and analyzed with FFT-analyzer. Vibration of catalyst cell was strongest at running speed of 5000 rpm, from 10 to 20 g (1 g equals 9.81 ms-2), when catalyst was attached rigidly close to the engine. At running speed of 3000 rpm, vibration of catalyst cell was from 2 to 3 g in most cases, when catalyst was attached either rigidly or flexible to the engine. It is estimated that in real life, i.e. when catalyst is attached to car with same engine, vibration of catalyst cell at running speed of 5000 rpm is somewhere between 1 and 10 g. At running speed of 3000 rpm, which may be more often used when driving car (car speed approximately 100 kmh-1), vibration of catalyst cell is probably few g's.

  15. Wear behaviors of pure aluminum and extruded aluminum alloy (AA2024-T4) under variable vertical loads and linear speeds

    Science.gov (United States)

    Jung, Jeki; Oak, Jeong-Jung; Kim, Yong-Hwan; Cho, Yi Je; Park, Yong Ho

    2017-11-01

    The aim of this study was to investigate the transition of wear behavior for pure aluminum and extruded aluminum alloy 2024-T4 (AA2024-T4). The wear test was carried using a ball-on-disc wear testing machine at various vertical loads and linear speeds. The transition of wear behaviors was analyzed based on the microstructure, wear tracks, wear cross-section, and wear debris. The critical wear rates for each material are occurred at lower linear speed for each vertical load. The transition of wear behavior was observed in which abrasion wears with the generation of an oxide layer, fracture of oxide layer, adhesion wear, severe adhesion wear, and the generation of seizure occurred in sequence. In case of the pure aluminum, the change of wear debris occurred in the order of blocky, flake, and needle-like debris. Cutting chip, flake-like, and coarse flake-like debris was occurred in sequence for the extruded AA2024-T4. The transition in the wear behavior of extruded AA2024-T4 occurred slower than in pure aluminum.

  16. Catalyst for microelectromechanical systems microreactors

    Science.gov (United States)

    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

    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. Influence of space size of abutment screw access channel on the amount of extruded excess cement and marginal accuracy of cement-retained single implant restorations.

    Science.gov (United States)

    Al Amri, Mohammad D; Al-Johany, Sulieman S; Al-Qarni, Mohammed N; Al-Bakri, Ahmed S; Al-Maflehi, Nassr S; Abualsaud, Haythem S

    2018-02-01

    The detrimental effect of extruded excess cement on peri-implant tissue has been well documented. Although several techniques have been proposed to reduce this effect by decreasing the amount of extruded cement, how the space size of the abutment screw access channel (SAC) affects the amount of extruded cement and marginal accuracy is unclear. The purpose of this in vitro study was to evaluate the effect of the size of the unfilled space of the abutment SAC on the amount of extruded excess cement and the marginal accuracy of zirconia copings. Twelve implant replicas and corresponding standard abutments were attached and embedded in acrylic resin blocks. Computer-aided design and computer-aided manufacturing (CAD-CAM) zirconia copings with a uniform 30-μm cement space were fabricated by 1 dental technician using the standard method. The copings were temporarily cemented 3 times at different sizes of the left space of the SAC as follows: the nonspaced group (NS), in which the entire SAC was completely filled, the 1-mm-spaced group (1MMS), and the 2-mm-spaced group (2MMS). Abutments and crowns were ultrasonically cleaned, steam cleaned, and air-dried. The excess cement was collected and weighed. To measure the marginal accuracy, 20 measurements were made every 18 degrees along the coping margin at ×300 magnification and compared with the pre-cementation readings. One-way ANOVA was calculated to determine whether the amount of extruded excess cement differed among the 3 groups, and the Tukey test was applied for multiple comparisons (α=.05). The mean weights (mg) of extruded excess cement were NS (33.53 ±1.5), 1MMS (22.97 ±5.4), and 2MMS (15.17 ±5.9). Multiple comparisons showed significant differences in the amount of extruded excess cement among the 3 test groups (Pcemented group (29.5 ±8.2) was significantly different (Pcement by 55% in comparison with the nonspaced abutments. However, no effect was found on the marginal accuracy of zirconia copings

  18. Improvement in the traditional processing method and nutritional quality of traditional extruded cassava-based snack (modified Ajogun).

    Science.gov (United States)

    Obadina, Adewale O; Oyewole, Olusola B; Williams, Oluwasolabomi E

    2013-07-01

    This study was carried out to investigate and improve the traditional processing method and nutritional quality of the traditional cassava snack (Ajogun). Cassava root (Manihot esculenta Crantz L.) of TME 419 variety was processed into mash (40% moisture content). The cassava mash was mixed into different blends to produce fried traditional "Ajogun", fried and baked extrudates (modified Ajogun) as snacks. These products were analyzed to determine the proximate composition including carbohydrate, fat, protein, fiber, ash, and moisture contents and functional properties such as bulk density. The results obtained for the moisture, fat, protein, and ash contents showed significant difference (P extrudates. However, there was no significant difference (P > 0.05) in the carbohydrate and fiber contents between the three samples. There was no significant difference (P > 0.05) in the bulk density of the snacks. Also, sensory evaluation was carried out on the cassava-based snacks using the 9-point hedonic scale to determine the degree of acceptability. Results obtained showed significant difference (P extrudates and control sample in terms of appearance, taste, flavor, color, aroma, texture, and overall acceptability. The highest acceptability level of the product was at 8.04 for the control sample (traditional Ajogun). This study has shown that "Ajogun", which is a lesser known cassava product, is rich in protein and fat.

  19. 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

  20. Production of palm frond based wood plastic composite by using twin screw extruder

    Science.gov (United States)

    Russita, M.; Bahruddin

    2018-04-01

    Wood plastic composite (WPC) is the blending product from wood as filler and polymer thermoplastic as matric. Palm frond waste is a material with selulose about 68%, so it has potential to be developed as raw material for WPC. The purpose of this research was to learn how to produce WPC based on palm frond use twin screw extruder. It used popropilen as matric. As for aditif, it used Maleated Polypropilene (MAPP) as compatibilizer and paraffin as plasticizer. The size of palm frond is 40 – 80 mesh. WPC is made from blending polipropylene, palm frond, MAPP and paraffin with dry mixing method in room temperature. Then, PP, Palm frond and additive from dry mixing is fed into twin screw extruder at 190°C and 60 rpm. It use palm frond/polypropylene 60/40, MAPP 5% w/w and paraffin 2% w/w. From the result, it shown that WPC based on palm frond met the standards forcommercial WPC. It has tensile strength up to 19.2 MPa, bending strength 43.6 MPa and water adsorption 0,32% w/w. So, WPC based on palm frond has prospective to be developed for commercial WPC.

  1. Effects of formulation and process conditions on microstructure, texture and digestibility of extruded insect-riched snacks

    NARCIS (Netherlands)

    Azzollini, D.; Derossi, A.; Fogliano, V.; Lakemond, C.M.M.; Severini, C.

    2018-01-01

    Extruded cereals made of wheat flour and grinded Yellow mealworm larvae (Tenebrio molitor) were produced to investigate the effect of insect inclusion (0%, 10%, 20%) and processing conditions (barrel temperature and screw speed) on their nutritional content, microstructure, texture and

  2. 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

  3. Study of the cooling process of an extruded aluminium profile

    International Nuclear Information System (INIS)

    Bouffioux, C.; Habraken, A.M.; Carton, M.; Lecomte-Beckers, J.

    2004-01-01

    The prediction of the final axial stresses and the residual strains of complex extruded aluminium profiles requires a good knowledge of the material behavior and of the industrial process. This paper is focused on the methods required to provide the whole set of data: material ones and process ones. Scanning differential calorimetry, dilatometry and diffusivity tests identify thermophysic material properties and hot tensile tests identify parameters of the elasto-visco-plastic Norton-Hoff law. The description of the industrial process and its simulations are described. Then a sensitivity analyzis provides the cooling key parameters causing the undesired final curvature during the industrial process

  4. Continuous thickness control of extruded pipes with assistance of microcomputers

    International Nuclear Information System (INIS)

    Breil, J.

    1983-06-01

    Because of economic and quality securing reasons a constant wall thickness of extruded pipes in circumference and extrusion direction is an important production aim. Therefore a microcomputer controlled system was developed, which controls die centering with electric motors. The control of wall thickness distribution; was realized with two conceptions: a dead time subjected control with a rotating on line wall thickness measuring instrument and an adaptive control with sensors in the pipe die. With a PI-algorithm excentricities of 30% of the wall thickness could be controlled below a trigger level of 2% within three dead times. (orig.) [de

  5. Catalysts for synthetic liquid fuels

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, L.A.; Turney, T.W.

    1987-12-01

    Fischer-Tropsch catalysts have been designed, characterized and tested for the selective production of hydrocarbons suitable as synthetic liquid transport fuels from synthesis gas (i.e., by the reduction of carbon monoxide with hydrogen). It was found that hydrocarbons in the middle distillate range, or suitable for conversion to that range, could be produced over several of the new catalyst systems. The various catalysts examined included: (1) synthetic cobalt clays, mainly cobalt chlorites; (2) cobalt hydrotalcites; (3) ruthenium metal supported on rare earth oxides of high surface area; and (4) a novel promoted cobalt catalyst. Active and selective catalysts have been obtained, in each category. With the exception of the clays, reproducibility of catalyst performance has been good. Catalysts in groups 2 and 4 have exhibited very high activity, with long lifetimes and easy regeneration.

  6. Synthesis H-Zeolite catalyst by impregnation KI/KIO3 and performance test catalyst for biodiesel production

    Science.gov (United States)

    Widayat, W.; Rizky Wicaksono, Adit; Hakim Firdaus, Lukman; Okvitarini, Ndaru

    2016-02-01

    The objective of this research is to produce H-catalyst catalyst that was impregnated with KI/KIO3. The catalyst was analyzed about surface area, X-Ray Diffraction (XRD) and performance test of catalyst for biodiesel production. An H-Zeolite catalyst was synthesized from natural zeolite with chemical treatment processing, impregnation KI/KIO3 and physical treatment. The results shows that the surface area of the catalyst by 27.236 m2/g at a concentration of 5% KI. XRD analysis shows peak 2-θ at 23.627o indicating that KI was impregnated on H-zeolite catalyst. The catalyst was tested in production of biodiesel using palm oil with conventional methods for 3 hour at temperature of 70-80 oC. The result for conversion Fatty Acid Methyl Ester (FAME) reached maximum value on 87.91% under production process using catalyst 5% KIO3-H zeolite.

  7. Regeneration of LOHC dehydrogenation catalysts: In-situ IR spectroscopy on single crystals, model catalysts, and real catalysts from UHV to near ambient pressure

    International Nuclear Information System (INIS)

    Amende, Max; Kaftan, Andre; Bachmann, Philipp; Brehmer, Richard; Preuster, Patrick; Koch, Marcus

    2016-01-01

    Graphical abstract: - Highlights: • We examine the regeneration of Pt-based catalysts poisoned by LOHC degradation. • A microscopic mechanism of the removal of degradation products from Pt is proposed. • Results of our UHV studies on model catalysts are transferred to real catalysis. • Oxidative regeneration of Pt/alumina is possible under mild conditions (600 K). • The degree and temperature regime of regeneration depends on the catalyst morphology. - Abstract: The Liquid Organic Hydrogen Carrier (LOHC) concept offers an efficient route to store hydrogen using organic compounds that are reversibly hydrogenated and dehydrogenated. One important challenge towards application of the LOHC technology at a larger scale is to minimize degradation of Pt-based dehydrogenation catalysts during long-term operation. Herein, we investigate the regeneration of Pt/alumina catalysts poisoned by LOHC degradation. We combine ultrahigh vacuum (UHV) studies on Pt(111), investigations on well-defined Pt/Al_2O_3 model catalysts, and near-ambient pressure (NAP) measurements on real core–shell Pt/Al_2O_3 catalyst pellets. The catalysts were purposely poisoned by reaction with the LOHC perhydro-dibenzyltoluene (H18-MSH) and with dicyclohexylmethane (DCHM) as a simpler model compound. We focus on oxidative regeneration under conditions that may be applied in real dehydrogenation reactors. The degree of poisoning and regeneration under oxidative reaction conditions was quantified using CO as a probe molecule and measured by infrared reflection-absorption spectroscopy (IRAS) and diffuse reflectance Fourier transform IR spectroscopy (DRIFTS) for planar model systems and real catalysts, respectively. We find that regeneration strongly depends on the composition of the catalyst surface. While the clean surface of a poisoned Pt(111) single crystal is fully restored upon thermal treatment in oxygen up to 700 K, contaminated Pt/Al_2O_3 model catalyst and core–shell pellet were only

  8. Regeneration of LOHC dehydrogenation catalysts: In-situ IR spectroscopy on single crystals, model catalysts, and real catalysts from UHV to near ambient pressure

    Energy Technology Data Exchange (ETDEWEB)

    Amende, Max, E-mail: max.amende@fau.de [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany); Kaftan, Andre, E-mail: andre.kaftan@fau.de [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany); Bachmann, Philipp, E-mail: philipp.bachmann@fau.de [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany); Brehmer, Richard, E-mail: richard.brehmer@fau.de [Lehrstuhl für Chemische Reaktionstechnik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany); Preuster, Patrick, E-mail: patrick.preuster@fau.de [Lehrstuhl für Chemische Reaktionstechnik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany); Koch, Marcus, E-mail: marcus.koch@crt.cbi.uni-erlangen.de [Lehrstuhl für Chemische Reaktionstechnik, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen (Germany); and others

    2016-01-01

    Graphical abstract: - Highlights: • We examine the regeneration of Pt-based catalysts poisoned by LOHC degradation. • A microscopic mechanism of the removal of degradation products from Pt is proposed. • Results of our UHV studies on model catalysts are transferred to real catalysis. • Oxidative regeneration of Pt/alumina is possible under mild conditions (600 K). • The degree and temperature regime of regeneration depends on the catalyst morphology. - Abstract: The Liquid Organic Hydrogen Carrier (LOHC) concept offers an efficient route to store hydrogen using organic compounds that are reversibly hydrogenated and dehydrogenated. One important challenge towards application of the LOHC technology at a larger scale is to minimize degradation of Pt-based dehydrogenation catalysts during long-term operation. Herein, we investigate the regeneration of Pt/alumina catalysts poisoned by LOHC degradation. We combine ultrahigh vacuum (UHV) studies on Pt(111), investigations on well-defined Pt/Al{sub 2}O{sub 3} model catalysts, and near-ambient pressure (NAP) measurements on real core–shell Pt/Al{sub 2}O{sub 3} catalyst pellets. The catalysts were purposely poisoned by reaction with the LOHC perhydro-dibenzyltoluene (H18-MSH) and with dicyclohexylmethane (DCHM) as a simpler model compound. We focus on oxidative regeneration under conditions that may be applied in real dehydrogenation reactors. The degree of poisoning and regeneration under oxidative reaction conditions was quantified using CO as a probe molecule and measured by infrared reflection-absorption spectroscopy (IRAS) and diffuse reflectance Fourier transform IR spectroscopy (DRIFTS) for planar model systems and real catalysts, respectively. We find that regeneration strongly depends on the composition of the catalyst surface. While the clean surface of a poisoned Pt(111) single crystal is fully restored upon thermal treatment in oxygen up to 700 K, contaminated Pt/Al{sub 2}O{sub 3} model catalyst and

  9. 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.

  10. 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 STANDARDS...

  11. 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.

  12. 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.

  13. 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.

  14. Spent catalyst waste management. A review. Part 1. Developments in hydroprocessing catalyst waste reduction and use

    Energy Technology Data Exchange (ETDEWEB)

    Marafi, M.; Stanislaus, A. [Petroleum Refining Department, Petroleum Research and Studies Center, Kuwait Institute for Scientific Research, P.O. Box 24885, 13109-Safat (Kuwait)

    2008-04-15

    Solid catalysts containing metals, metal oxides or sulfides, which play a key role in the refining of petroleum to clean fuels and many other valuable products, become solid wastes after use. In many refineries, the spent catalysts discarded from hydroprocessing units form a major part of these solid wastes. Disposal of spent hydroprocessing catalysts requires compliance with stringent environmental regulations because of their hazardous nature and toxic chemicals content. Various options such as minimizing spent catalyst waste generation by regeneration and reuse, metals recovery, utilization to produce useful materials and treatment for safe disposal, could be considered to deal with the spent catalyst environmental problem. In this paper, information available in the literature on spent hydroprocessing catalyst waste reduction at source by using improved more active and more stable catalysts, regeneration, rejuvenation and reuse of deactivated catalysts in many cycles, and reusing in other processes are reviewed in detail with focus on recent developments. Available methods for recycling of spent hydroprocessing catalysts by using them as raw materials for the preparation of active new catalysts and many other valuable products are also reviewed. (author)

  15. Raw mechanically separated chicken meat and salmon protein hydrolysate as protein sources in extruded dog food

    DEFF Research Database (Denmark)

    Tjernsbekk, M. T.; Tauson, A. H.; Kraugerud, O. F.

    2017-01-01

    Protein quality was evaluated for mechanically separated chicken meat (MSC) and salmon protein hydrolysate (SPH), and for extruded dog foods where MSC or SPH partially replaced poultry meal (PM). Apparent total tract digestibility (ATTD) of crude protein (CP) and amino acids (AA) in the protein...

  16. Automotive Catalyst State Diagnosis Using Microwaves

    Directory of Open Access Journals (Sweden)

    Moos Ralf

    2015-01-01

    Full Text Available The state of catalysts plays a key role in automotive exhaust gas aftertreatment. The soot or ash loading of Diesel particulate filters, the oxygen loading degree in three-way catalysts, the amount of stored ammonia in SCR catalysts, or the NOx loading degree in NOx storage catalysts are important parameters that are today determined indirectly and in a model-based manner with gas sensors installed upstream and/or downstream of the catalysts. This contribution gives an overview on a novel approach to determine the catalyst state directly by a microwave-based technique. The method exploits the fact that the catalyst housing acts as a microwave cavity resonator. As “sensing” elements, one or two simple antennas are mounted inside the catalyst canning. The electrical properties of the catalyst device (ceramic honeycomb plus coating and storage material can be measured. Preferably, the resonance characteristics, e.g., the resonance frequencies, of selected cavity modes are observed. The information on the catalyst interior obtained in such a contactless manner is very well correlated with the catalyst state as will be demonstrated for different exhaust gas aftertreatment systems.

  17. 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

  18. Enrichment of extruded snack products with coproducts from chestnut mushroom (Agrocybe aegerita) production: interactions between dietary fiber, physicochemical characteristics, and glycemic load.

    Science.gov (United States)

    Brennan, Margaret A; Derbyshire, Emma; Tiwari, Brijesh K; Brennan, Charles S

    2012-05-02

    Mushrooms are a common vegetable product that have also been linked to pharmaceutical and medicinal uses. However, the production of the fruiting bodies of mushrooms results in a large quantity of food waste in the form of spent compost. Hyphae and the base of fruit bodies from Agrocybe aegerita were retrieved from spent mushroom compost and refined as a freeze-dried powder. This fiber-rich ingredient was used in the manufacture of ready-to-eat extruded cereal snack products. Inclusions rates were 0, 5, 10, and 15% w/w replacement levels for wheat flour from a control recipe. Inclusion of mushroom coproduct material (MCM) was significantly correlated to increased product expansion (r = 0.848) and density (r = 0.949) but negatively correlated to water absorption index (WAI; r = -0.928) and water solubility index (WSI; r = -0.729). Fiber content could not be correlated to differences in pasting properties of extruded snacks even though snack products with MCM showed significantly lower final viscosity values compared to the control. The potential glycemic response of foods was significantly lowered by including MCM (p extruded snacks (r = 0.916, 0.851, and 0.878. respectively). The results illustrate a reduction in the potential glycemic response from including 5% (w/w) of MCM in extruded snacks exceeds 20%. Thus, the incorporation of MCM in ready-to-eat snack foods may be of considerable interest to the food industry in trying to regulate the glycemic response of foods.

  19. Impact of Lubricant Additives on thePhysicochemical Properties and Activity of Three‐Way Catalysts

    Directory of Open Access Journals (Sweden)

    Chao Xie

    2016-04-01

    Full Text Available As alternative lubricant anti‐wear additives are sought to reduce friction and improve overall fuel economy, it is important that these additives are also compatible with current emissions control catalysts. In the present work, an oil‐miscible phosphorous‐containing ionic liquid (IL, trihexyltetradecylphosphonium bis(2‐ethylhexyl phosphate ([P66614][DEHP], is evaluated for its impact on three‐way catalysts (TWC and benchmarked against the industry standard zinc‐dialkyl‐dithio‐phosphate (ZDDP. The TWCs are aged in different scenarios: neat gasoline (no‐additive, or NA, gasoline+ZDDP, and gasoline+IL. The aged samples, along with the as‐received TWC, are characterized through various analytical techniques including catalyst reactivity evaluation in a bench‐flow reactor. The temperatures of 50% conversion (T50 for the ZDDP‐aged TWCs increased by 30, 24, and 25 °C for NO, CO, and C3H6, respectively, compared to the no‐additive case. Although the IL‐aged TWC also increased in T50 for CO and C3H6, it was notably less than ZDDP, 7 and 9 °C, respectively. Additionally, the IL‐aged samples had higher water‐gas‐shift reactivity and oxygen storage capacity than the ZDDP‐aged TWC. Characterization of the aged samples indicated the predominant presence of CePO4 in the ZDDP‐aged TWC aged by ZDDP, while its formation was retarded in the case of IL where higher levels of AlPO4 is observed. Thus, results in this work indicate that the phosphonium‐phosphate IL potentially has less adverse impact on TWC than ZDDP.

  20. Metallographic Index-Based Quantification of the Homogenization State in Extrudable Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Panagiota I. Sarafoglou

    2016-05-01

    Full Text Available Extrudability of aluminum alloys of the 6xxx series is highly dependent on the microstructure of the homogenized billets. It is therefore very important to characterize quantitatively the state of homogenization of the as-cast billets. The quantification of the homogenization state was based on the measurement of specific microstructural indices, which describe the size and shape of the intermetallics and indicate the state of homogenization. The indices evaluated were the following: aspect ratio (AR, which is the ratio of the maximum to the minimum diameter of the particles, feret (F, which is the maximum caliper length, and circularity (C, which is a measure of how closely a particle resembles a circle in a 2D metallographic section. The method included extensive metallographic work and the measurement of a large number of particles, including a statistical analysis, in order to investigate the effect of homogenization time. Among the indices examined, the circularity index exhibited the most consistent variation with homogenization time. The lowest value of the circularity index coincided with the metallographic observation for necklace formation. Shorter homogenization times resulted in intermediate homogenization stages involving rounding of edges or particle pinching. The results indicated that the index-based quantification of the homogenization state could provide a credible method for the selection of homogenization process parameters towards enhanced extrudability.

  1. Centralization of extruded medial meniscus delays cartilage degeneration in rats.

    Science.gov (United States)

    Ozeki, Nobutake; Muneta, Takeshi; Kawabata, Kenichi; Koga, Hideyuki; Nakagawa, Yusuke; Saito, Ryusuke; Udo, Mio; Yanagisawa, Katsuaki; Ohara, Toshiyuki; Mochizuki, Tomoyuki; Tsuji, Kunikazu; Saito, Tomoyuki; Sekiya, Ichiro

    2017-05-01

    Meniscus extrusion often observed in knee osteoarthritis has a strong correlation with the progression of cartilage degeneration and symptom in the patients. We recently reported a novel procedure "arthroscopic centralization" in which the capsule was sutured to the edge of the tibial plateau to reduce meniscus extrusion in the human knee. However, there is no animal model to study the efficacy of this procedure. The purposes of this study were [1] to establish a model of centralization for the extruded medial meniscus in a rat model; and [2] to investigate the chondroprotective effect of this procedure. Medial meniscus extrusion was induced by the release of the anterior synovial capsule and the transection of the meniscotibial ligament. Centralization was performed by the pulled-out suture technique. Alternatively, control rats had only the medial meniscus extrusion surgery. Medial meniscus extrusion was evaluated by micro-CT and macroscopic findings. Cartilage degeneration of the medial tibial plateau was evaluated macroscopically and histologically. By micro-CT analysis, the medial meniscus extrusion was significantly improved in the centralization group in comparison to the extrusion group throughout the study. Both macroscopically and histologically, the cartilage lesion of the medial tibial plateau was prevented in the centralization group but was apparent in the control group. We developed medial meniscus extrusion in a rat model, and centralization of the extruded medial meniscus by the pull-out suture technique improved the medial meniscus extrusion and delayed cartilage degeneration, though the effect was limited. Centralization is a promising treatment to prevent the progression of osteoarthritis. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Hydroprocessing catalysts utilization and regeneration schemes

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.

    The catalyst reactor inventory represents an important part of the cost of hydroprocessing operation. The selection of a suitable catalyst and reactor is influenced by feedstock properties. Processes ensuring an uninterrupted operation during catalyst addition and withdrawal are preferred for processing high asphaltene and metal content feedstocks. The spent catalyst can be regenerated and returned to the operation if the extent of its deactivation is not high. The regeneration may be performed either in-situ or off-site. The former is suitable for fixed bed reactors whereas the catalyst from ebullated bed reactors must be regenerated off-site. The regeneration of spent catalysts heavily loaded with metals such as V, Ni and Fe may not be economic. Such catalysts may be suitable for metal reclamation. An environmentally safe method for catalyst disposal must be found if neither regeneration nor metal reclamation from spent catalysts can be performed.

  3. Alternative alkali resistant deNOx catalysts

    DEFF Research Database (Denmark)

    Putluru, Siva Sankar Reddy; Kristensen, Steffen Buus; Due-Hansen, Johannes

    2012-01-01

    by onepot sol–gel method. All catalysts were characterized by BET, XRPD and NH3-TPD. Initial SCR activities of 8 out of 9 catalysts showed higher NO conversion at least at one temperature in the temperature range 300–500 ◦C compared to the conventional V2O5-WO3/TiO2 catalyst. After potassium poisoning (100......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......–130 µmol of K/g of catalyst) the relative drop in SCR activity and acidity was lower for all the alternative catalysts compared to the industrial V2O5-WO3/TiO2 catalyst. Furthermore, Cu/MOR and Nano-V2O5/Sul-TiO2 catalysts showed 8–16 times higher SCR activities than the conventional even after high...

  4. 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

  5. 78 FR 58520 - Extruded Rubber Thread From Malaysia; Notice of Amended Final Results of Antidumping Duty...

    Science.gov (United States)

    2013-09-24

    ... Malaysia; Notice of Amended Final Results of Antidumping Duty Administrative Review AGENCY: Import... from Malaysia.\\1\\ The period of review (POR) is October 1, 1995, through September 30, 1996. \\1\\ See Extruded Rubber Thread From Malaysia; Final Results of Antidumping Duty Administrative Review, 63 FR 12752...

  6. ALKALI RESISTANT CATALYST

    DEFF Research Database (Denmark)

    2008-01-01

    The present invention concerns the selective removal of nitrogen oxides (NOx) from gasses. In particular, the invention concerns a process, a catalyst and the use of a catalyst for the selective removal of nitrogen oxides in the presence of ammonia from gases containing a significant amount...... of alkali metal and/or alkali-earth compounds which process comprises using a catalyst combined of (i) a formed porous superacidic support, said superacidic support having an Hammett acidity stronger than Ho=-12, and (ii) a metal oxide catalytic component deposited on said superacidic support selected from...

  7. 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)

    Komatsu, Tamikuni; Tomokuni, Keizou; Yamada, Issaku

    2006-01-01

    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 150-200 o C and free from difficult problems of SOx-deactivation and hydrothermal ageing of the NOx-absorption-reduction catalyst. (author)

  8. Effect of Quenching Rate on Microstructure and Hardness of Al-Zn-Mg-Cu-Cr Alloy Extruded Bar

    Directory of Open Access Journals (Sweden)

    HAN Su-qi

    2017-04-01

    Full Text Available The effect of quenching rate on microstructure and hardness of Al-Zn-Mg-Cu-Cr alloy extruded bar was studied by hardness test, scanning electron microscopy and transmission electron microscopy. The results show that at quenching rate below 100℃/s, during the cooling process, the hardness begins to fall significantly; and it decreases by 43% at the quenching rate of 2℃/s. At quenching rate below 100℃/s, the number and size of equilibrium η phase heterogeneously nucleated at(subgrain boundaries and on dispersoids inside grains increase obviously with the decrease of quenching rate, leading to greatly reduced age-hardening response. At the same quenching rate, the equilibrium η phase inside grains is larger than that at grain boundaries. In the range of the studied quenching rates, a quantitative relationship between hardness and equilibrium η phase area fraction has been established.

  9. Paraffin Alkylation Using Zeolite Catalysts in a slurry reactor: Chemical Engineering Principles to Extend Catalyst Lifetime

    NARCIS (Netherlands)

    Jong, K.P. de; Mesters, C.M.A.M.; Peferoen, D.G.R.; Brugge, P.T.M. van; Groot, C. de

    1996-01-01

    The alkylation of isobutane with 2-butene is carried out using a zeolitic catalyst in a well stirred slurry reactor. Whereas application of fixed bed technology using a solid acid alkylation catalyst has in the led to catalysts lifetimes in the range of minutes, in this work we report catalyst

  10. Hydroxide catalysts for lignin depolymerization

    Science.gov (United States)

    Beckham, Gregg T; Biddy, Mary J.; Kruger, Jacob S.; Chmely, Stephen C.; Sturgeon, Matthew

    2017-10-17

    Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

  11. Hydroxide catalysts for lignin depolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Beckham, Gregg T.; Biddy, Mary J.; Chmely, Stephen C.; Sturgeon, Matthew

    2017-04-25

    Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

  12. Hydrous titanium oxide-supported catalysts

    International Nuclear Information System (INIS)

    Dosch, R.G.; Stohl, F.V.; Richardson, J.T.

    1990-01-01

    Catalysts were prepared on hydrous titanium oxide (HTO) supports by ion exchange of an active metal for Na + ions incorporated in the HTO support during preparation by reaction with the parent Ti alkoxide. Strong active metal-HTO interactions as a result of the ion exchange reaction can require significantly different conditions for activation as compared to catalysts prepared by more widely used incipient wetness methods. The latter catalysts typically involve conversion or while the HTO catalysts require the alteration of electrostatic bonds between the metal and support with subsequent alteration of the support itself. In this paper, the authors discuss the activation, via sulfidation or reduction, of catalysts consisting of Co, Mo, or Ni-Mo dispersed on HTO supports by ion exchange. Correlations between the activation process and the hydrogenation, hydrodeoxygenation, and hydrodesulfurization activities of the catalysts are presented

  13. Coatings of active and heat-resistant cobalt-aluminium xerogel catalysts.

    Science.gov (United States)

    Schubert, Miriam; Schubert, Lennart; Thomé, Andreas; Kiewidt, Lars; Rosebrock, Christopher; Thöming, Jorg; Roessner, Frank; Bäumer, Marcus

    2016-09-01

    The application of catalytically coated metallic foams in catalytic processes has a high potential for exothermic catalytic reactions such as CO2 methanation or Fischer-Tropsch synthesis due to good heat conductivity, improved turbulent flow properties and high catalyst efficiencies. But the preparation of homogenous catalyst coats without pore blocking is challenging with conventional wash coating techniques. Here, we report on a stable and additive free colloidal CoAlOOH suspension (sol) for the preparation of catalytically active Co/Al2O3 xerogel catalysts and coatings. Powders with 18wt% Co3O4 prepared from this additive free synthesis route show a catalytic activity in Fischer-Tropsch synthesis and CO2 methanation which is similar to a catalyst prepared by incipient wetness impregnation (IWI) after activating the material under flowing hydrogen at 430°C. Yet, the xerogel catalyst exhibits a much higher thermal stability as compared to the IWI catalyst, as demonstrated in catalytic tests after different heat agings between 430°C and 580°C. It was also found that the addition of polyethylene glycol (PEG) to the sol influences the catalytic properties of the formed xerogels negatively. Only non-reducible cobalt spinels were formed from a CoAlOOH sol with 20wt% PEG. Metallic foams with pores sizes between 450 and 1200μm were coated with the additive free CoAlOOH sol, which resulted in homogenous xerogel layers. First catalytic tests of the coated metal foams (1200μm) showed good performance in CO2 methanation. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Soot oxidation over NOx storage catalysts. Activity and deactivation

    International Nuclear Information System (INIS)

    Krishna, K.; Makkee, M.

    2006-01-01

    Soot oxidation activity and deactivation of NO x storage and reduction (NSR) catalysts containing Pt, K, and Ba supported on Al 2 O 3 , are studied under a variety of reaction conditions. K-containing catalysts decrease soot oxidation temperature with O 2 alone and the presence of Pt further enhance the activity due to synergetic effect. The active species responsible for synergism on Pt/K-Al 2 O 3 are unstable and cannot be regenerated. Soot oxidation temperature decreases by about 150 o C with NO+O 2 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 NO 2 followed by NO recycles to NO 2 , and (2) soot oxidation with O 2 assisted by NO 2 . Only a part of the stored NO x that is decomposed at high temperatures under lean conditions is found to be useful for soot oxidation. NO x 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-Al 2 O 3 catalyst is more active, but least stable compared with Pt/Ba-Al 2 O 3 . (author)

  15. Methanol conversion to hydrocarbons using modified clinoptilolite catalysts. Investigation of catalyst lifetime and reactivation

    Energy Technology Data Exchange (ETDEWEB)

    Hutchings, G J; Themistocleous, T; Copperthwaite, R G

    1988-10-17

    A study of the deactivation and reactivation of modified clinoptilolite catalysts for methanol conversion to hydrocarbons is reported. Clinoptilolite catalysts, modified by either ammonium ion exchange or hydrochloric acid treatment, exhibit a short useful catalyst lifetime for this reaction (ca. 2-3 h) due to a high rate of coke deposition (3-5.10/sup -3/ g carbon/g catalyst/h). A comparative study of reactivation using oxygen, nitrous oxide and ozone/oxygen as oxidants indicated that nitrous oxide reactivation gives improved catalytic performance when compared to the activity and lifetime of the fresh catalyst. Both oxygen and ozone/oxygen were found to be ineffective for the reactivation of clinoptilolite. Initial studies of in situ on-line reactivation are also described. 3 figs., 15 refs., 4 tabs.

  16. The influence of determining the working length with an apex locator on the amount of apically extruded debris following instrumentation with ProTaper Next and HyFlex CM

    Directory of Open Access Journals (Sweden)

    Ersan Çiçek

    2016-01-01

    Full Text Available Aim: The amount of apically extruded debris caused by new nickel-titanium rotary systems after determination of the working length (WL with an apex locator has not been investigated. To compare the amount of apically extruded debris with ProTaper Next (PTN and HyFlex CM systems after determination of WL with/without an apex locator. Materials and Methods: Forty-eight extracted mandibular incisor teeth divided into four groups were used in this study. In Groups 1 and 2, a 10 K-file was progressed until it was just visible at the major apical foramen and WL was recorded as 1 mm short. In Groups 3 and 4, the WL was determined with the Root ZX (sensitivity of 0.1 using a 10 K-file. During the instrumentation, the PTN was used to X2 in groups 1 and 3, and the HyFlex CM was used to 25/.06 in groups 2 and 4. Distilled water was used as an irrigant. Debris was collected in tubes then stored in an incubator at 68°C for 5 days to evaporate the distilled water. The Eppendorf tubes, including the extruded debris, were weighed to obtain final weights. The amount of extruded debris was calculated by subtracting the weight of the empty tube from the weight of the dry tube. Data were analyzed by Kruskal–Wallis and Mann–Whitney U-test. Results: Less apically extruded debris was obtained in Group 3, with a significant difference compared to Group 1 and Group 2 (P < 0.05. Conclusions: The usage of apex locator to determine the WL decreased the amount of apically extruded debris. In addition, PTN caused less apical debris extrusion after determination WL with/without apex locator.

  17. Magnetic catalyst bodies

    NARCIS (Netherlands)

    Teunissen, Wendy; Bol, A.A.; Geus, John W.

    1999-01-01

    After a discussion about the importance of the size of the catalyst bodies with reactions in the liquid-phase with a suspended catalyst, the possibilities of magnetic separation are dealt with. Deficiencies of the usual ferromagnetic particles are the reactivity and the clustering of the

  18. 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.

  19. Development of micronutrients rich homemade extruded food products with the incorporation of processed foxtail millet, wheat and chickpea

    Directory of Open Access Journals (Sweden)

    L Gautam

    2014-12-01

    Full Text Available Background: Food based approaches are recognized as an essential part of an urgently needed more comprehensive strategy for improving nutrition by increasing the availability and consumption to combat iron and other micronutrient deficiencies. Aims & Objective: The specific objective of the study was utilization of Foxtail millet (Setariaitalica along with other flour for production of micronutrients rich ready-to-eat snack products using homemade extrusion cooking. Material and methods: Methods Composite flour were prepared using processed Foxtail millet flour (FMF and other processed flours namely; wheat flour (WF, and chick pea flour (CPF. Nutritional properties of the blends were analyzed by using standard procedure. Two homemade extruded products namely; namkeensev, seviyan were prepared with four treatments T0, T1, T2, & T3. The commonly consumed recipes were developed by incorporating 50%, 75% and 100% of best result malted composite flour (FMF+CPF+WF. Results: The organoleptic qualities of these extruded samples were analyzed by panelists on a 9 point hedonic scale. The result indicate that the processed composite flour (FMF+CPF+WF based products were significantly accepted at the level of p<0.05 50% incorporation followed by 75% and 100% respectively. Conclusions: The present study conclude that, processed composite flour (Foxtail millet; wheat; chickpea in the ratios of (50:50 could be used to produce nutritive quality of homemade extrudates with acceptable sensory properties as they deliver vehicles for malnourished children.

  20. Development of micronutrients rich homemade extruded food products with the incorporation of processed foxtail millet, wheat and chickpea

    Directory of Open Access Journals (Sweden)

    L Gautam

    2014-12-01

    Full Text Available Background: Food based approaches are recognized as an essential part of an urgently needed more comprehensive strategy for improving nutrition by increasing the availability and consumption to combat iron and other micronutrient deficiencies. Aims & Objective: The specific objective of the study was utilization of Foxtail millet (Setariaitalica along with other flour for production of micronutrients rich ready-to-eat snack products using homemade extrusion cooking. Material and methods: Methods Composite flour were prepared using processed Foxtail millet flour (FMF and other processed flours namely; wheat flour (WF, and chick pea flour (CPF. Nutritional properties of the blends were analyzed by using standard procedure. Two homemade extruded products namely; namkeensev, seviyan were prepared with four treatments T0, T1, T2, & T3. The commonly consumed recipes were developed by incorporating 50%, 75% and 100% of best result malted composite flour (FMF+CPF+WF. Results: The organoleptic qualities of these extruded samples were analyzed by panelists on a 9 point hedonic scale. The result indicate that the processed composite flour (FMF+CPF+WF based products were significantly accepted at the level of p<0.05 50% incorporation followed by 75% and 100% respectively. Conclusions: The present study conclude that, processed composite flour (Foxtail millet; wheat; chickpea in the ratios of (50:50 could be used to produce nutritive quality of homemade extrudates with acceptable sensory properties as they deliver vehicles for malnourished children.

  1. Development of GREET Catalyst Module

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhichao [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Dunn, Jennifer B. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Cronauer, Donald C. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division

    2014-09-01

    Catalysts are critical inputs for many pathways that convert biomass into biofuels. Energy consumption and greenhouse gas (GHG) emissions during the production of catalysts and chemical inputs influence the life-cycle energy consumption, and GHG emissions of biofuels and need to be considered in biofuel life-cycle analysis (LCA). In this report, we develop energy and material flows for the production of three different catalysts (tar reforming, alcohol synthesis, Zeolite Socony Mobil-5 [ZSM-5]) 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. They were selected because they are consumed in existing U.S. Department of Energy (DOE) analyses of biofuel processes. For example, a thermochemical ethanol production pathway (indirect gasification and mixed alcohol synthesis) developed by the National Renewable Energy Laboratory (NREL) uses olivine, DEPG, and tar reforming and alcohol synthesis catalysts (Dutta et al., 2011). ZSM-5 can be used in biofuel production pathways such as catalytic upgrading of sugars into hydrocarbons (Biddy and Jones, 2013). Other uses for these compounds and catalysts are certainly possible. In this report, we document the data sources and methodology we used to develop material and energy flows for the catalysts and compounds in the GREET catalyst module. In Section 2 we focus on compounds used in the model Dutta et al. (2011) developed. In Section 3, we report material and energy flows associated with ZSM-5 production. Finally, in Section 4, we report results.

  2. Effect of composition in the development of carbamazepine hot-melt extruded solid dispersions by application of mixture experimental design.

    Science.gov (United States)

    Djuris, Jelena; Ioannis, Nikolakakis; Ibric, Svetlana; Djuric, Zorica; Kachrimanis, Kyriakos

    2014-02-01

    This study investigates the application of hot-melt extrusion for the formulation of carbamazepine (CBZ) solid dispersions, using polyethyleneglycol-polyvinyl caprolactam-polyvinyl acetate grafted copolymer (Soluplus, BASF, Germany) and polyoxyethylene-polyoxypropylene block copolymer (Poloxamer 407). In agreement with the current Quality by Design principle, formulations of solid dispersions were prepared according to a D-optimal mixture experimental design, and the influence of formulation composition on the properties of the dispersions (CBZ heat of fusion and release rate) was estimated. Prepared solid dispersions were characterized using differential scanning calorimetry, attenuated total reflectance infrared spectroscopy and hot stage microscopy, as well as by determination of the dissolution rate of CBZ from the hot-melt extrudates. Solid dispersions of CBZ can be successfully prepared using the novel copolymer Soluplus. Inclusion of Poloxamer 407 as a plasticizer facilitated the processing and decreased the hardness of hot-melt extrudates. Regardless of their composition, all hot-melt extrudates displayed an improvement in the release rate compared to the pure CBZ, with formulations having the ratio of CBZ : Poloxamer 407 = 1 : 1 showing the highest increase in CBZ release rate. Interactions between the mixture components (CBZ and polymers), or quadratic effects of the components, play a significant role in overall influence on the CBZ release rate. © 2013 Royal Pharmaceutical Society.

  3. Texture development in gluten-free breads: Effect of different enzymes and extruded flour

    OpenAIRE

    Martínez, Mario M.; Marcos, Pablo; Gómez, Manuel

    2013-01-01

    Producción Científica One of the main problems with gluten-free breads is their texture and their rapid staling. In this work the influence of different enzymes (one protease, one lipase and two amylases) and of extruded rice flour on rice-bread texture and texture development was studied. For this purpose, the development of firmness, cohesiveness, resilience, springiness and chewiness was modelled and the parameters that define the initial values and the development of these characterist...

  4. Fischer-Tropsch Synthesis over Iron Manganese Catalysts: Effect of Preparation and Operating Conditions on Catalyst Performance

    Directory of Open Access Journals (Sweden)

    Ali A. Mirzaei

    2009-01-01

    molar basis which is the most active catalyst for the conversion of synthesis gas to light olefins. The effects of different promoters and supports with loading of optimum support on the catalytic performance of catalysts are also studied. It was found that the catalyst containing 50%Fe/50%Mn/5 wt.%Al2O3 is an optimum-modified catalyst. The catalytic performance of optimal catalyst has been studied in operation conditions such as a range of reaction temperatures, H2/CO molar feed ratios and a range of total pressures. Characterization of both precursors and calcined catalysts is carried out by powder X-ray diffraction (XRD, scanning electron microscopy (SEM, BET specific surface area and thermal analysis methods such as TGA and DSC.

  5. Oxidative desulfurization of synthetic diesel using supported catalysts. Part 3. Support effect on vanadium-based catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Cedeno-Caero, Luis; Gomez-Bernal, Hilda; Fraustro-Cuevas, Adriana; Guerra-Gomez, Hector D.; Cuevas-Garcia, Rogelio [UNICAT, Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Cd. Universitaria 04510, Mexico D.F. (Mexico)

    2008-04-15

    Oxidesulfurization (ODS) of benzothiophenic compounds prevailing in diesel was conducted with hydrogen peroxide in presence of various catalysts, using a model diesel and actual diesel fuel. ODS activities of dibenzothiophenes (DBTs) in hexadecane for a series of V{sub 2}O{sub 5} catalysts supported on alumina, titania, ceria, niobia and silica, were evaluated. Results show that the oxidation activity of DBTs depends on the support used. It was observed that the sulfone yield is not proportional to textural properties or V content. For all catalysts, ODS of benzothiophene (BT), dibenzothiophene (DBT), 4-methyl dibenzothiophene (4-MDBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT) decreased in the following order: DBT > 4-MDBT > 4,6-DMDBT > BT. This trend does not depend on the catalyst used or the textural properties of the catalysts and supports. In presence of indole ODS activities diminish, except with catalysts supported on alumina-titania mixed oxide, whereas with V{sub 2}O{sub 5}/TiO{sub 2} catalyst the performance is the highest. ODS of Mexican diesel fuel was carried out in presence of this catalyst and S level was diminished in about 99%. (author)

  6. Autothermal reforming catalyst having perovskite structure

    Science.gov (United States)

    Krumpel, Michael [Naperville, IL; Liu, Di-Jia [Naperville, IL

    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.

  7. Isotope exchange in oxide-containing catalyst

    Science.gov (United States)

    Brown, Kenneth G. (Inventor); Upchurch, Billy T. (Inventor); Hess, Robert V. (Inventor); Miller, Irvin M. (Inventor); Schryer, David R. (Inventor); Sidney, Barry D. (Inventor); Wood, George M. (Inventor); Hoyt, Ronald F. (Inventor)

    1989-01-01

    A method of exchanging rare-isotope oxygen for common-isotope oxygen in the top several layers of an oxide-containing catalyst is disclosed. A sample of an oxide-containing catalyst is exposed to a flowing stream of reducing gas in an inert carrier gas at a temperature suitable for the removal of the reactive common-isotope oxygen atoms from the surface layer or layers of the catalyst without damaging the catalyst structure. The reduction temperature must be higher than any at which the catalyst will subsequently operate. Sufficient reducing gas is used to allow removal of all the reactive common-isotope oxygen atoms in the top several layers of the catalyst. The catalyst is then reoxidized with the desired rare-isotope oxygen in sufficient quantity to replace all of the common-isotope oxygen that was removed.

  8. Physical, textural, and antioxidant properties of extruded waxy wheat flour snack supplemented with several varieties of bran

    Science.gov (United States)

    Wheat represents a ubiquitous commodity and while industries valorize 10% of wheat bran, most of this antioxidant-rich byproduct gets discarded. The objective of this study was to incorporate wheat bran into an extruded snack. Bran varieties from hard red spring, white club Bruehl, and purple whea...

  9. Bifunctional cobalt F-T catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.G.; Coughlin, P.K.; Yang, C.L.; Rabo, J.A.

    1986-03-01

    Results on the catalytic screening of Fischer-Tropsch catalysts containing shape selective components are reported. Catalysts consist of promoted cobalt intimately contacted with Union Carbide molecular sieves and were tested using a Berty type internally recycled reactor. Methods of preparation, promoters and shape selective components were varied and aimed at improving catalyst performance. Catalysts were developed demonstrating high C/sub 5/ + yields with high olefin content and low methane production while maintaining stability under both low and high H/sub 2/:CO ratio conditions.

  10. 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...... 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...

  11. Development and Optimization of a Wet Granulation Process at Elevated Temperature for a Poorly Compactible Drug Using Twin Screw Extruder for Continuous Manufacturing.

    Science.gov (United States)

    Meena, Anuprabha K; Desai, Divyakant; Serajuddin, Abu T M

    2017-02-01

    The objective of this study was to enhance tabletability of a poorly compactible drug, acetaminophen, by wet granulation using twin screw extruder at high temperature. It was desired that there would be minimum amounts of excipients used and the granules obtained after extrusion would be dry and fall within a size range suitable for tableting without any further processing. Mixtures of acetaminophen (95%) with binders (5% povidone or partially pregelatinized starch) were wet granulated through twin screw extruder at 70°C by adding 7% w/w water. The process had a short granulation time (processing temperature used, no drying after extrusion was needed. By optimizing formulation and processing parameters, >90% granules in the size range of 125 to 1000 μm (1.7 MPa, which was superior to that of tablets prepared by conventional high shear wet granulation. As the granules could be extruded continuously and did not require drying and milling, the method was amenable to continuous processing. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  12. Oxygen-reducing catalyst layer

    Science.gov (United States)

    O'Brien, Dennis P [Maplewood, MN; Schmoeckel, Alison K [Stillwater, MN; Vernstrom, George D [Cottage Grove, MN; Atanasoski, Radoslav [Edina, MN; Wood, Thomas E [Stillwater, MN; Yang, Ruizhi [Halifax, CA; Easton, E Bradley [Halifax, CA; Dahn, Jeffrey R [Hubley, CA; O'Neill, David G [Lake Elmo, MN

    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.

  13. Apically extruded debris with reciprocating single-file and full-sequence rotary instrumentation systems.

    Science.gov (United States)

    Bürklein, Sebastian; Schäfer, Edgar

    2012-06-01

    The purpose of this in vitro study was to assess the amount of apically extruded debris using rotary and reciprocating nickel-titanium instrumentation systems. Eighty human mandibular central incisors were randomly assigned to 4 groups (n = 20 teeth per group). The root canals were instrumented according to the manufacturers' instructions using the 2 reciprocating single-file systems Reciproc (VDW, Munich, Germany) and WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) and the 2 full-sequence rotary Mtwo (VDW, Munich, Germany) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) instruments. Bidistilled water was used as irrigant. The apically extruded debris was collected in preweighted glass vials using the Myers and Montgomery method. After drying, the mean weight of debris was assessed with a microbalance and statistically analyzed using analysis of variance and the post hoc Student-Newman-Keuls test. The time required to prepare the canals with the different instruments was also recorded. The reciprocating files produced significantly more debris compared with both rotary systems (P rotary instruments (P > .05), the reciprocating single-file system Reciproc produced significantly more debris compared with all other instruments (P Instrumentation was significantly faster using Reciproc than with all other instrument (P rotary instrumentation was associated with less debris extrusion compared with the use of reciprocating single-file systems. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. 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.

  15. Citric acid induced promoted dispersion of Pt on the support and enhanced catalytic activities for a Pt-based catalyst

    Science.gov (United States)

    Cheng, Tianqiong; Wang, Jianli; Wang, Suning; Cui, Yajuan; Zhang, Hailong; Yan, Shuang; Yuan, Shandong; Chen, Yaoqiang

    2017-12-01

    Citric acid (CA), as the chelating agent, was introduced to obtain the enhanced Pt dispersion and catalytic activities for the Pt-based catalysts supported on oxygen-storage material. The role and content of CA were investigated systematically. It was found that the citric acid-assisted catalysts showed better Pt dispersion and smaller nanoparticle size of Pt. Thus, the catalyst had lower reduction temperature, preferable thermostability and possessed more oxidation state of Pt species under the oxidation atmosphere. The citric acid-induced fresh catalysts were excellent to convert CO and the corresponding aged ones exhibited higher activities for the elimination of all the target pollutants. Among the aged catalysts, P2-a (the mole ratio of Pt/CA is 2:1) presented the best performance. Particularly, compared with the reference sample (Pc-a), the light-off temperatures (T50) of NO, HC and CO for P2-a decreased by 39 °C, 42 °C and 72 °C, respectively, and the full-conversion temperatures (T90) of NO, HC and CO for P2-a decreased by 44 °C, 44 °C and 48 °C, respectively. Therefore, this work provides a facile and valid method to manufacture advanced catalysts for purification of the vehicle exhaust in the future.

  16. Whole extruded linseed in the diet of dairy ewes during early lactation: effect on the fatty acid composition of milk and cheese

    Directory of Open Access Journals (Sweden)

    P. Secchiari

    2010-04-01

    Full Text Available In a long term supplementation trial (10 weeks, the effects of the inclusion of whole extruded linseed in the diet of dairy ewes on milk and cheese fatty acid composition were evaluated. Two groups of 24 Sarda ewes in early lactation were randomly assigned to control concentrate (800 g/d concentrate, C or whole extruded linseed concentrate (L, 700 g/d, with 30% of extruded linseed, Omega-Lin®. Results showed that, after 2 weeks on the L diet, the milk content of unsaturated fatty acid (UFA, including rumenic acid (RA, vaccenic acid (VA and alfa-linolenic acid (ALA increased sharply compared to C group, reaching the highest levels after 7-8 weeks (3.06, 7.31 and 2.31 g/100 g milk fat for RA, VA and ALA, respectively. During the last 2 weeks of the experimental period, when pasture was included in the diet of both groups, the content of the above fatty acids slightly decreased in milk from L group, whereas in milk from C group increased. Nevertheless, the average content of these fatty acids in milk from L group remained significantly higher than that of milk from C group. Compared with the control, the L diet resulted in a significant reduction (-17% in the concentration of saturated fatty acid in milk. The fatty acid content of the cheese obtained from milk of the two groups reflected the milk fatty acid composition. The inclusion of extruded linseed in the diet of dairy ewes improved the nutraceutical properties of milk and cheese, but further researches are needed in order to better understand the relationship between basal diet and lipid supplementation in dairy ewes.

  17. 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.

  18. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Metal catalysts fight back

    OpenAIRE

    George Marsh

    1998-01-01

    In recent years organometallic catalysts, especially metallocenes, have been a major focus of attention in terms of polymerisation chemistry. But the news earlier this year of a family of iron-based catalysts able to rival the effectiveness of both conventional and metallocene catalysts in the polymerisation of ethylene has excited the plastics industry. Because of the impact of this discovery and its potential as a route to lower-priced commodity plastics in the future, it may be useful at t...

  20. Emission behaviors of nitrous oxide from automobiles. 4th Report. Aging effect of three way catalyst on N2O mass emissions; Jidosha kara haishutsusareru asanka chisso (N2O) no haishutsu kyodo ni kansuru kenkyu. 4. Sangen shokubai no rekka ga N2O haishutsuryo ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Koike, N; Suzuki, H; Odaka, M [Traffic Safety and Nuisance Research Institute, Tokyo (Japan)

    1997-10-01

    Several kind of three way catalysts with different metal compositions have been developed for trial and their N2O formation behaviors before and after the durability tests have been observed. Then by comparing the N2O formation behavior between new and durability tested catalysts, N2O increase mechanism with aging has been experimentally analyzed. As results, A catalyst temperature at peak N2O formation will sift to higher side by the aging and enters in the range that is the higher percentage in use during test cycle driving. Then this is the main cause of increase in total N2O emission. 4 refs., 10 figs., 2 tabs.

  1. Rejuvenation of the SCR catalyst at Mehrum

    Energy Technology Data Exchange (ETDEWEB)

    Nagai, Y.; Inatsume, Y.; Morita, I.; Kato, Y.; Yokoyama, K.; Ito, K. [Babcock Hitachi K.K., Kure-shi, Hiroshima-ken (Japan)

    2004-07-01

    Babcock Hitachi K.K. (BHK) received the contract of the rejuvenation of the SCR catalyst at the 750 MW coal-fired Mehrum Power Station (in Hohenhameln, Germany) in March 2003. The contractual coverage was 160 m{sup 3} of the entire catalyst layer. The catalyst, which had been in operation for 16 years since 1987, was originally supplied by BHK. The rejuvenation process developed for the Mehrum project consisted of two major steps: the first is to dust off the catalyst and remove the catalyst poison, and the second step is to add active material to enhance the catalyst activity. The catalyst must be dried after each washing. In order to minimize transportation cost and time, the rejuvenation work was done at the Mehrum station site. The scope of the rejuvenation work was shared between the owner and BHK. It took about one and a half months to complete the (total) on-site rejuvenation worked. The performance of the rejuvenated catalyst was superior to show the same level of activity as the unused catalyst and maintain the same SO{sub 2} conversion rate as the spent catalyst. This paper gives the details of the spent coal-fired SCR catalyst rejuvenation work. 13 figs., 1 tab.

  2. Productions of palm oil bio diesel whit heterogeneous basic catalysts compared to conventional homogeneous catalysts

    International Nuclear Information System (INIS)

    Rios, Luis A; Franco C, Alexander; Zuleta S, Ernesto

    2009-01-01

    The conventional process to produce biodiesel involves the presence of homogeneous basic catalysts. However, these catalysts have disadvantages associated to the need of purification steps, which increase the cost of the final product and generate pollution problems caused by the effluents. This paper compares different homogeneous and heterogeneous catalysts for the biodiesel production from palm oil. For this, heterogeneous catalysts supported on alumina were prepared and characterized by nitrogen adsorption, scanning electron microscopy, energy dispersive X ray spectroscopy and X ray diffraction. Transesterification of palm oil with methanol was accomplished at 60 celsius degrade and one hour, varying methanol/oil ratio, the type of catalyst and its concentration. Yields of the reaction and purity of the so obtained biodiesel were evaluated. Comparing the catalysts performance, based on the amount, was found that sodium methoxide (CH 3 ONa) and potassium carbonate supported on alumina (K 2 CO 3 /Al 2 O 3 ) were the catalysts that give the higher purity of biodiesel (96.8 and 95.85% respectively). When was determined the active site quality, by dividing the performance by each mole of active sites, it was found that calcined Na 2 SO 4 /Al 2 O 3 has the most active sites.

  3. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Novel metalloporphyrin catalysts for the oxidation of hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Showalter, M.C.; Nenoff, T.M.; Shelnutt, J.A.

    1996-11-01

    Work was done for developing biomimetic oxidation catalysts. Two classes of metalloporphyrin catalysts were studied. The first class of catalysts studied were a novel series of highly substituted metalloporphyrins, the fluorinated iron dodecaphenylporphyrins. These homogeneous metalloporphyrin catalysts were screened for activity as catalysts in the oxidation of hydrocarbons by dioxygen. Results are discussed with respect to catalyst structural features. The second type of catalysts studied were heterogeneous catalysts consisting of metalloporphyrins applied to inorganic supports. Preliminary catalytic testing results with these materials are presented.

  5. Optimal catalyst curves: Connecting density functional theory calculations with industrial reactor design and catalyst selection

    DEFF Research Database (Denmark)

    Jacobsen, C.J.H.; Dahl, Søren; Boisen, A.

    2002-01-01

    For ammonia synthesis catalysts a volcano-type relationship has been found experimentally. We demonstrate that by combining density functional theory calculations with a microkinetic model the position of the maximum of the volcano curve is sensitive to the reaction conditions. The catalytic...... ammonia synthesis activity, to a first approximation, is a function only of the binding energy of nitrogen to the catalyst. Therefore, it is possible to evaluate which nitrogen binding energy is optimal under given reaction conditions. This leads to the concept of optimal catalyst curves, which illustrate...... the nitrogen binding energies of the optimal catalysts at different temperatures, pressures, and synthesis gas compositions. Using this concept together with the ability to prepare catalysts with desired binding energies it is possible to optimize the ammonia process. In this way a link between first...

  6. Request Twin Screw Extruder to Enhance DoD Interested Polymer Nanocomposite Research and STEM Program

    Science.gov (United States)

    2016-09-25

    will provide more African American STEM workforces to the nation. (a) Papers published in peer-reviewed journals (N/A for none) Enter List of papers...include polymer/carbon nanocomposites, polymer/calcium phosphate composites, and etc , which are within the technical fields of interest to the DoD...e.g. Kalvar), polycarbonate, and textured products, cellulose pulps, etc . Therefore, this twin-screw extruder not only strengthened existing

  7. 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

  8. 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)

  9. CO methanation over supported bimetallic Ni-Fe catalysts: From computational studies towards catalyst optimization

    DEFF Research Database (Denmark)

    Kustov, Arkadii; Frey, Anne Mette; Larsen, Kasper Emil

    2007-01-01

    with compositions 25Fe75Ni and 50Fe50Ni showed significantly better activity and in some cases also a higher selectivity to methane compared with the traditional monometallic Ni and Fe catalysts. A catalyst with composition 25Fe75Ni was found to be the most active in CO hydrogenation for the MgAl2O4 support at low...... metal loadings. At high metal concentrations, the maximum for the methanation activity was found for catalysts with composition 50Ni50Fe both on the MgAl2O4 and Al2O3 supports. This difference can be attributed to a higher reducibility of the constituting metals with increasing metal concentration......DFT calculations combined with a computational screening method have previously shown that bimetallic Ni-Fe alloys should be more active than the traditional Ni-based catalyst for CO methanation. That was confirmed experimentally for a number of bimetallic Ni-Fe catalysts supported on MgAl2O4. Here...

  10. 40Ar-39Ar age of a lava flow from the Bhimashankar Formation ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    from the Bhimashankar Formation (Fm.), Giravali Ghat, western Deccan province, India. This age is consistent with the view that the 1.8–2 km thick bottom part of the exposed basalt flow sequence in the Western Ghats was extruded very close to 67.4 Ma. 1. Introduction. The Deccan flood basalt province (DFBP) of.

  11. 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.

  12. Enhanced activity of Pt/CNTs anode catalyst for direct methanol fuel cells using Ni2P as co-catalyst

    Science.gov (United States)

    Li, Xiang; Luo, Lanping; Peng, Feng; Wang, Hongjuan; Yu, Hao

    2018-03-01

    The direct methanol fuel cell is a promising energy conversion device because of the utilization of the state-of-the-art platinum (Pt) anode catalyst. In this work, novel Pt/Ni2P/CNTs catalysts were prepared by the H2 reduction method. It was found that the activity and stability of Pt for methanol oxidation reaction (MOR) could be significantly enhanced while using nickel phosphide (Ni2P) nanoparticles as co-catalyst. X-ray photoelectron spectroscopy revealed that the existence of Ni2P affected the particle size and electronic distribution of Pt obviously. Pt/CNTs catalyst, Pt/Ni2P/CNTs catalysts with different Ni2P amount were synthesized, among which Pt/6%Ni2P/CNTs catalyst exhibited the best MOR activity of 1400 mAmg-1Pt, which was almost 2.5 times of the commercial Pt/C-JM catalyst. Moreover, compared to other Pt-based catalysts, this novel Pt/Ni2P/CNTs catalyst also exhibited higher onset current density and better steady current density. The result of this work may provide positive guidance to the research on high efficiency and stability of Pt-based catalyst for direct methanol fuel cells.

  13. Improving the API dissolution rate during pharmaceutical hot-melt extrusion I: Effect of the API particle size, and the co-rotating, twin-screw extruder screw configuration on the API dissolution rate.

    Science.gov (United States)

    Li, Meng; Gogos, Costas G; Ioannidis, Nicolas

    2015-01-15

    The dissolution rate of the active pharmaceutical ingredients in pharmaceutical hot-melt extrusion is the most critical elementary step during the extrusion of amorphous solid solutions - total dissolution has to be achieved within the short residence time in the extruder. Dissolution and dissolution rates are affected by process, material and equipment variables. In this work, we examine the effect of one of the material variables and one of the equipment variables, namely, the API particle size and extruder screw configuration on the API dissolution rate, in a co-rotating, twin-screw extruder. By rapidly removing the extruder screws from the barrel after achieving a steady state, we collected samples along the length of the extruder screws that were characterized by polarized optical microscopy (POM) and differential scanning calorimetry (DSC) to determine the amount of undissolved API. Analyses of samples indicate that reduction of particle size of the API and appropriate selection of screw design can markedly improve the dissolution rate of the API during extrusion. In addition, angle of repose measurements and light microscopy images show that the reduction of particle size of the API can improve the flowability of the physical mixture feed and the adhesiveness between its components, respectively, through dry coating of the polymer particles by the API particles. Copyright © 2014. Published by Elsevier B.V.

  14. Rare earth metals for automotive exhaust catalysts

    International Nuclear Information System (INIS)

    Shinjoh, Hirohumi

    2006-01-01

    The usage of rare earth metals for automotive exhaust catalysts is demonstrated in this paper. Rare earth metals have been widely used in automotive catalysts. In particular, three-way catalysts require the use of ceria compounds as oxygen storage materials, and lanthana as both a stabilizer of alumina and a promoter. The application for diesel catalysts is also illustrated. Effects of inclusion of rare earth metals in automotive catalysts are discussed

  15. Alkaline Ionic Liquid Modified Pd/C Catalyst as an Efficient Catalyst for Oxidation of 5-Hydroxymethylfurfural

    Directory of Open Access Journals (Sweden)

    Zou Bin

    2018-01-01

    Full Text Available Conversion of HMF into FDCA was carried out by a simple and green process based on alkaline ionic liquid (IL modified Pd/C catalyst (Pd/C-OH−. Alkaline ionic liquids were chosen to optimize Pd/C catalyst for special hydrophilicity and hydrophobicity, redox stability, and unique dissolving abilities for polar compounds. The Pd/C-OH− catalyst was successfully prepared and characterized by SEM, XRD, TG, FT-IR, and CO2-TPD technologies. Loading of alkaline ionic liquid on the surface of Pd/C was 2.54 mmol·g−1. The catalyst showed excellent catalytic activity in the HMF oxidation after optimization of reaction temperature, reaction time, catalyst amount, and solvent. Supported alkaline ionic liquid (IL could be a substitute and promotion for homogeneous base (NaOH. Under optimal reaction conditions, high HMF conversion of 100% and FDCA yield of 82.39% were achieved over Pd/C-OH− catalyst in water at 373 K for 24 h.

  16. Carbonaceous deposits on naptha reforming catalysts

    International Nuclear Information System (INIS)

    Redwan, D.S.

    1999-01-01

    Carbonaceous deposits on naphtha reforming catalysts play a decisive role in limiting process performance. The deposits negatively after catalyst activity, selectivity and the production cycle of a semi regenerative reformer. The magnitude of negative effect of those deposits is directly proportional to their amounts and complexity. Investigations on used reforming catalysts samples reveal that the amount and type (complexity of the chemical nature) of carbonaceous deposits are directly proportional to the catalysts life on stream and the severity of operating conditions. In addition, the combustibility behavior of carbonaceous deposits on the catalyst samples taken from different reformers are found to be different. Optimal carbon removal, for in situ catalyst regeneration, requires the specific conditions be developed, based on the results of well designed and properly performed investigations of the amount and type of carbonaceous deposits. (author)

  17. Reducible oxide based catalysts

    Science.gov (United States)

    Thompson, Levi T.; Kim, Chang Hwan; Bej, Shyamal K.

    2010-04-06

    A catalyst is disclosed herein. The catalyst includes a reducible oxide support and at least one noble metal fixed on the reducible oxide support. The noble metal(s) is loaded on the support at a substantially constant temperature and pH.

  18. A Journey along the Extruder with Polystyrene : C60 Nanocomposites: Convergence of Feeding Formulations into a Similar Nanomorphology

    NARCIS (Netherlands)

    Gaspar, Hugo; Teixeira, Paulo; Santos, Raquel; Fernandes, Liliana; Hilliou, Loic; Weir, Michael P.; Parnell, Andrew J.; Abrams, Kerry J.; Hill, Christopher J.; Bouwman, W.G.; Parnell, S.R.; King, Stephen M.; Clarke, Nigel; Covas, Jose A.; Bernardo, Gabriel

    2017-01-01

    We investigated the effect of the feeding formulation (premixed powders of pure components versus solvent-blended mixture) of polystyrene–C60 composites on the dispersion and reagglomeration phenomena developing along the barrel of a twin-screw extruder. The dispersion of C60 in the PS matrix is

  19. Increasing the lifetime of fuel cell catalysts

    NARCIS (Netherlands)

    Latsuzbaia, R.

    2015-01-01

    In this thesis, I discuss a novel idea of fuel cell catalyst regeneration to increase lifetime of the PEM fuel cell electrode/catalyst operation and, therefore, reduce the catalyst costs. As many of the catalyst degradation mechanisms are difficult to avoid, the regeneration is alternative option to

  20. Hydroprocessing using regenerated spent heavy hydrocarbon catalyst

    International Nuclear Information System (INIS)

    Clark, F.T.; Hensley, A.L. Jr.

    1992-01-01

    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

  1. pH-dependent release of trace elements including platinum group elements (PGEs) from gasoline and diesel catalysts

    Science.gov (United States)

    Sucha, Veronika; Mihaljevic, Martin; Ettler, Vojtech; Strnad, Ladislav

    2014-05-01

    The release of trace metals and platinum group elements (PGEs) from automobile exhaust catalysts represents a remarkable source of higly dispersed environmental contamination. Especially, PGEs have shown increasing research interest due to their possible bioaccessibility. In our research, we focused on leaching behaviour of trace metals from gasoline and diesel automobile catalysts. While catalysts for gasoline engines contain a mixture of Pt-Pd-Rh or Pd-Rh, catalysts for diesel engines are composed only of Pt. We used dust from two crushed gasoline and two crushed diesel catalysts (new and aged). The dust of gasoline catalysts contains significant concentrations of Pt (700 mg.kg-1), Pd (11 000 mg.kg-1) and Rh (700 mg.kg-1). And the dust of diesel catalysts are composed of Pt (3 900 mg.kg-1) and they contains negligible amounts of Pd dan Rh (leaching of trace metals from dust we used pH-stat leaching test according to the European standard CEN/TS 14997. The concentrations of cations: PGEs (Pt, Pd a Rh), K, Na, Ca, Mg, Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb, La and Ce were determined by inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS), and anions: F-, Cl-, SO42- and NO3- by high-performance liquid chromatography. Although the dusts from catalysts were relatively stable to acid/base influence, the leaching of trace metals from catalysts showed a dependence on pH. Generally, the highest concentrations were released under acidic conditions. The leaching of PGEs was higher for Pt in diesel catalysts and for Pd and Rh in gasoline catalysts. The highest concentrations of Zn and Pb were observed in old catalysts. The rare earth metals were released more from gasoline catalysts. Catalysts particles represent health risk especially with respect to their PGEs contents.

  2. Replacement of steel parts with extruded aluminum alloys in an automobile

    Science.gov (United States)

    Daggula, Manikantha Reddy

    Over the past years, vehicle emissions have shown a negative impact on environment and human health. A new strategy has been used by automakers to reduce a vehicle's weight which significantly reduce fuel consumption and C02 emissions. A very light car consumes very less fuel as it needs to overcome less inertia, decreasing the required power to movie the vehicle. Reducing weight is the easiest way to increase fuel economy and making it by just 10% can increase its efficiency 6 to 8 percent. For a normal scale 80% of vehicles weight is shared among chassis, power train and other exterior components. Almost 60% of the vehicles weight is comprised of steel and the remaining is with cast and extruded aluminum and magnesium alloys. Our main aim is to look for the parts like Fuel tank holder, Fuel filler neck, Turbo inlet assembly, and Brake lines, Dash board frame which are made from steel and replace them with extruded aluminum alloys, to analyze a conventional rear wheel aluminum drive shaft and replace it with a new design and with a new aluminum alloy. The current project involves dismantling an automobile and looking for feasible steel parts and making samples, analyzing the hardness of the samples. These parts are optimally analyzed using Ansys Finite element analysis tool, these parts are subjected to the constraints such as three-point bending, tensile testing, hydrostatic pressure and also torsional stress action on the drive shaft, the deformation and stress are observed in these parts. The results show the current steel parts can be replaced with 3000 series aluminum alloy and the drive shaft can be replaced with new design with 6061-T6 Al-alloy which decreases 25% of the shaft weight.

  3. Development and evaluation of garlic incorporated ready-to-eat extruded snacks.

    Science.gov (United States)

    Haritha, D; Vijayalakshmi, V; Gulla, S

    2014-11-01

    The present study was carried out to develop and evaluate ready to eat extruded snacks incorporated with garlic powder at various levels (5 %, 10 %, 15 %, 20 %). The organoleptic evaluation was conducted for the developed products and the well accepted products were selected for further studies like physical properties and shelf life (stored at room temperature for 2 months). The organoleptic evaluation of the developed snacks revealed that 15 % and 20 % garlic incorporated snacks were not acceptable due to strong garlic flavor, therefore T1 (control), T2 (5 % garlic) and T3 ( 10 % garlic) were selected for further studies. The physical properties showed significant changes with incorporation of garlic powder at 0 %-10 % level. There was an increase in mass flow rate, tap density and bulk density but decrease in the water holding capacity, oil absorption capacity and expansion ratio. The water soluble index and moisture retention of the products showed the same values for all the three selected treatments. The products were packed by ordinary, nitrogen and vacuum packing and stored for 2 months. It was found that there was an increase in moisture content and microbial load, however the increase was within limits. The increase in the moisture content was low in nitrogen packed products where as the microbial load decreased with increase in the percentage of garlic incorporation. The nitrogen and vacuum packed products showed less microbial load than the ordinary packed products. Garlic powder can be incorporated at 5 and 10 % levels in ready-to-eat extruded snacks with well acceptability and can be stored for a period of 2 months with nitrogen packing as an effective packaging.

  4. Extended Catalyst Longevity Via Supercritical Isobutane Regeneration of a Partially Deactivated USY Alkylation Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Daniel M. Ginosar; David N. Thompson; Kyle C. Burch; David J. Zalewski

    2005-05-01

    Off-line, in situ activity recovery of a partially deactivated USY zeolite catalyst used for isobutane/butene alkylation was examined in a continuous-flow reaction system employing supercritical isobutane. Catalyst samples were deactivated in a controlled manner by running them to either to a fixed butene conversion level of 95% or a fixed time on stream of three hours, and then exposing the catalyst to supercritical isobutane to restore activity. Activity recovery was determined by comparing alkylation activity before and after the regeneration step. Both single and multiple regenerations were performed. Use of a 95% butene conversion level criterion to terminate the reaction step afforded 86% activity recovery for a single regeneration and provided nine sequential reaction steps for the multiple regeneration studies. Employing a fixed 3 h time on stream criterion resulted in nearly complete activity recovery for a single regeneration, and 24 reaction steps were demonstrated in sequence for the multiple regeneration process, producing only minor product yield declines per step. This resulted in a 12-fold increase in catalyst longevity versus unregenerated catalyst.

  5. Effect of natural ageing on microstructure and mechanical properties of Mg–10Gd–2Y–0.8Zr Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Z., E-mail: yz750925@163.com; Duan, H.B.; Wang, Z.H.; Guo, Y.C.; Gao, P.H.; Li, J.P., E-mail: jp_li0416@163.com

    2015-11-11

    The effect of natural aging on the microstructure and mechanical properties of Mg–10 wt%Gd–2 wt%Y–0.5 wt%Zn–0.5 wt%Zr alloy (GW102) was investigated via optical microscopy (OM), field emission gun scanning electron microscopy (FEGSEM), high-resolution transmission electron microscopy (HRTEM), and differential scanning calorimetry (DSC). The results indicated that the natural placement had a significant effect on the microstructure, mechanical properties, and subsequent artificial aging behaviors of the extruded GW102 alloy. The α(Mg) isometric crystal of the as-extruded alloy was composed entirely of deformation structures, formed by several types of cross-slip. However, the deformation structure within α(Mg) was significantly reduced by performing a 3-year natural aging treatment after extrusion. Many strain-free zones were observed near the grain boundary. Moreover, the β″ phase precipitated within the α(Mg) crystalline grains. The alloy was subjected to a 3-year natural aging treatment, followed by artificial aging at 200 °C; the resulting hardness and tensile strength were relatively high during the early stage, but decreased significantly at peak aging and the time required to reach peak aging was shortened. In addition, an aging peak platform (44–132 h) was observed. Moreover, the formation of β″ and the reduction of the deformation zone at natural aging process promoted the subsequent artificial aging process.

  6. Effect of natural ageing on microstructure and mechanical properties of Mg–10Gd–2Y–0.8Zr Alloy

    International Nuclear Information System (INIS)

    Yang, Z.; Duan, H.B.; Wang, Z.H.; Guo, Y.C.; Gao, P.H.; Li, J.P.

    2015-01-01

    The effect of natural aging on the microstructure and mechanical properties of Mg–10 wt%Gd–2 wt%Y–0.5 wt%Zn–0.5 wt%Zr alloy (GW102) was investigated via optical microscopy (OM), field emission gun scanning electron microscopy (FEGSEM), high-resolution transmission electron microscopy (HRTEM), and differential scanning calorimetry (DSC). The results indicated that the natural placement had a significant effect on the microstructure, mechanical properties, and subsequent artificial aging behaviors of the extruded GW102 alloy. The α(Mg) isometric crystal of the as-extruded alloy was composed entirely of deformation structures, formed by several types of cross-slip. However, the deformation structure within α(Mg) was significantly reduced by performing a 3-year natural aging treatment after extrusion. Many strain-free zones were observed near the grain boundary. Moreover, the β″ phase precipitated within the α(Mg) crystalline grains. The alloy was subjected to a 3-year natural aging treatment, followed by artificial aging at 200 °C; the resulting hardness and tensile strength were relatively high during the early stage, but decreased significantly at peak aging and the time required to reach peak aging was shortened. In addition, an aging peak platform (44–132 h) was observed. Moreover, the formation of β″ and the reduction of the deformation zone at natural aging process promoted the subsequent artificial aging process.

  7. The Stability of Supported Gold Catalysts

    NARCIS (Netherlands)

    Masoud, Nazila

    2018-01-01

    Gold has supreme cultural and financial value and, in form of nanoparticles smaller than 10 nm, is a unique catalyst for different industrially relevant reactions. Intriguing properties of the gold catalysts have spurred demand in the chemical industry for Au catalysts, the application of which

  8. Mathematical modeling of the drying of extruded fish feed and its experimental demonstration

    DEFF Research Database (Denmark)

    Haubjerg, Anders Fjeldbo; Simonsen, B.; Løvgreen, S.

    This paper present a mathematical model for the drying of extruded fish feed pellets. The model relies on conservation balances for moisture and energy. Sorption isotherms from literature are used together with diffusion and transfer coefficients obtained from dual parameter regression analysis...... against experimental data. The lumped capacitance method for the estimation of the heat transfer coefficient is used. The model performs well at temperatures ± 5 °C from sorption isotherm specificity, and for different pellet sizes. There is a slight under-estimation of surface temperature of denser feed...

  9. Extraction of sunflower oil by twin screw extruder: screw configuration and operating condition effects

    Energy Technology Data Exchange (ETDEWEB)

    Kartika, I.A. [FATETA-IPB, Bogor (Indonesia). Department of Agroindustrial Technology; Pontalier, P.Y.; Rigal, L. [Laboratoire de Chimie Agro-Industrielle, UMR 1010 INRA/INP-ENSIACET, Toulouse (France)

    2006-12-15

    The objective of this study was to investigate the screw configuration allowing oil extraction from sunflower seeds with a twin-screw extruder. Experiments were conducted using a co-rotating twin-screw extruder. Five screw profiles were examined to define the best performance (oil extraction yield, specific mechanical energy and oil quality) by studying the influence of operating conditions, barrel temperature, screw speed and feed rate. Generally, the position and spacing between two reversed screw elements affected oil extraction yield. An increase of oil extraction yield was observed as the reversed screw elements were moved with increased spacing between two elements and with smaller pitch elements. In addition, oil extraction yield increased as barrel temperature, screw speed and feed rate were decreased. Highest oil extraction yield (85%) with best cake meal quality (residual oil content lower than 13%) was obtained under operating conditions of 120 {sup o}C, 75 rpm and 19 kg/h. Furthermore, the operating parameters influenced energy input. A decrease in barrel temperature and feed rate followed by an increase in screw speed increased energy input, particularly specific mechanical energy input. Effect of the operating parameters on oil quality was less important. In all experiments tested, the oil quality was very good. The acid value was below 2 mg of KOH/g of oil and total phosphorus content was low, below 100 mg/kg. (author)

  10. Surface Quality Improvement of AA6060 Aluminum Extruded Components through Liquid Nitrogen Mold Cooling

    Directory of Open Access Journals (Sweden)

    Andrea Francesco Ciuffini

    2018-06-01

    Full Text Available 6xxx aluminum alloys are suitable for the realization of both structural applications and architectural decorative elements, thanks to the combination of high corrosion resistance and good surface finish. In areas where the aesthetic aspects are fundamental, further improvements in surface quality are significant. The cooling of the extrusion mold via internal liquid nitrogen fluxes is emerging as an important innovation in aluminum extrusion. Nowadays, this innovation is providing a large-scale solution to obtain high quality surface finishes in extruded aluminum semi-finished products. These results are also coupled to a significant increase in productivity. The aim of the work is to compare the surface quality of both cooled liquid nitrogen molds and classically extruded products. In this work, adhesion phenomena, occurring during the extrusion between the mold and the flowing material, have been detected as the main causes of the presence of surface defects. The analysis also highlighted a strong increase in the surface quality whenever the extrusion mold was cooled with liquid nitrogen fluxes. This improvement has further been confirmed by an analysis performed on the finished products, after painting and chromium plating. This work on the AA6060 alloy has moreover proceeded to roughness measurements and metallographic analyses, to investigate the eventual occurrence of other possible benefits stemming from this new extrusion mold cooling technology.

  11. Nitrogen oxides storage catalysts containing cobalt

    Science.gov (United States)

    Lauterbach, Jochen; Snively, Christopher M.; Vijay, Rohit; Hendershot, Reed; Feist, Ben

    2010-10-12

    Nitrogen oxides (NO.sub.x) storage catalysts comprising cobalt and barium with a lean NO.sub.x storage ratio of 1.3 or greater. The NO.sub.x storage catalysts can be used to reduce NO.sub.x emissions from diesel or gas combustion engines by contacting the catalysts with the exhaust gas from the engines. The NO.sub.x storage catalysts can be one of the active components of a catalytic converter, which is used to treat exhaust gas from such engines.

  12. FCC catalyst technologies expand limits of process capability

    International Nuclear Information System (INIS)

    Leiby, S.

    1992-01-01

    This paper reports that over the past 30 or so years, many improvements in fluid catalytic cracking (FCC) operation have been achieved as the result of innovations in catalyst formulation. During the 1990s, new environmental regulations on issues such as reformulated gasoline will place new demands on both the refining industry and catalyst suppliers. An overview of cracking catalyst technology therefore seems in order. Today, high-technology innovations by catalyst manufacturers are rapid, but profit margins are slim. Catalyst formulations are shrouded in secrecy and probably depend almost as much on art as on science. Special formulations for specific cracking applications get the greatest emphasis today. To illustrate this point, OGJ's Worldwide Catalyst Report lists over 200 FCC catalyst designations. Catalysts containing components to enhance gasoline octane now account for about 70% of total U.S. FCC catalyst usage

  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

    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.

  14. Catalyst Deactivation and Regeneration in Low Temperature Ethanol Steam Reforming with Rh/CeO2-ZrO2 Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Hyun-Seog; Platon, Alex; Wang, Yong; King, David L.

    2006-08-01

    Rh/CeO2-ZrO2 catalysts with various CeO2/ZrO2 ratios have been applied to H2 production from ethanol steam reforming at low temperatures. The catalysts all deactivated with time on stream (TOS) at 350 C. The addition of 0.5% K has a beneficial effect on catalyst stability, while 5% K has a negative effect on catalytic activity. The catalyst could be regenerated considerably even at ambient temperature and could recover its initial activity after regeneration above 200 C with 1% O2. The results are most consistent with catalyst deactivation due to carbonaceous deposition on the catalyst.

  15. 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...

  16. A new dynamic recrystallisation model of an extruded Al-Cu-Li alloy during high-temperature deformation

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Bo; Deng, Lei; Wang, Xinyun, E-mail: wangxy_hust@163.com

    2015-02-11

    The high-temperature deformation behaviour and microstructure evolution of an extruded Al-Cu-Li alloy were investigated by compression tests conducted at various temperatures (613, 673 and 733 K) with various strain rates (0.001, 0.01, and 0.1 s{sup -1}). The results indicated that the deformation activation energy increased from 208.7 kJ/mol to 255.7 kJ/mol with an increase in strain from 0.1 to 0.7. The electron backscatter diffraction maps indicated that a dynamic recrystallisation occurred during the high-temperature deformation. Two types of recrystallisation mechanisms, grain boundary bulging and a grain boundary transformation from low misorientation to high misorientation, were considered as the mechanisms for controlling the formation of the recrystallised grains. A new dynamic recrystallisation model containing these two mechanisms was proposed to describe the microstructure evolution of the extruded Al-Cu-Li alloy. At the early stage of the deformation, the recrystallised grains were formed by grain boundary bulging along the original grain boundaries. With increasing strain, recrystallised grains were gradually generated in the deformed grains due to the transformation from low angle boundaries to high angle boundaries.

  17. Petroleum residue upgrading with dispersed catalysts. Part 1. Catalysts activity and selectivity

    Energy Technology Data Exchange (ETDEWEB)

    Panariti, N.; Del Bianco, A.; Del Piero, G. [ENITECNOLOGIE S.p.A, Via Maritano 26, 20097 San Donato Mil. (Italy); Marchionna, M. [SNAMPROGETTI S.p.A, Via Maritano 26, 20097 San Donato Mil. (Italy)

    2000-12-04

    The results of a study aimed at the identification of the relevant chemical aspects involved in the process of upgrading heavy feedstocks in the presence of dispersed catalysts are discussed. The catalytic activity of different compounds was compared in terms of products yields and quality. Moreover, a detailed and systematic characterization of the catalysts recovered at the end of the reactions was achieved. The experimental work provided quite a large set of data, allowing to investigate the factors that may affect catalyst activity (precursor solubility, rate of activation, degree of dispersion, presence of promoters, etc.). The results of this study demonstrate that the best performances are obtained by the microcrystalline molybdenite generated in situ by oil-soluble precursors. The nature of the organic ligand does not play a very relevant role in influencing the hydrogenation activity. The presence of phosphorus, however, significantly enhances hydrodemetallation, at least in terms of vanadium removal. Bimetallic precursors show a slight synergistic effect towards the hydrodesulfurization reaction. Microsized powdered catalyst precursors have a much lower catalytic activity compared to the oil-soluble ones.

  18. The Impact of Rendered Protein Meal Oxidation Level on Shelf-Life, Sensory Characteristics, and Acceptability in Extruded Pet Food.

    Science.gov (United States)

    Chanadang, Sirichat; Koppel, Kadri; Aldrich, Greg

    2016-07-28

    Pet foods are expected to have a shelf-life for 12 months or more. Sensory analysis can be used to determine changes in products and to estimate products' shelf-life. The objectives of this study were to (1) investigate how increasing levels of oxidation in rendered protein meals used to produce extruded pet food affected the sensory properties and (2) determine the effect of shelf-life on pet owners' acceptability of extruded pet food diet formulated without the use of preservative. Pet food diets contained beef meat bone meal (BMBM) and chicken byproduct meal (CBPM) in which the oxidation was retarded with ethoxyquin, mixed tocopherols, or none at all, and then extruded into dry pet foods. These samples represented low, medium, and high oxidation levels, respectively. Samples were stored for 0, 3, 6, 9, and 12 months at ambient temperature. Each time point, samples were evaluated by six highly trained descriptive panelists for sensory attributes related to oxidation. Samples without preservatives were chosen for the acceptability test, since the differences in sensory characteristics over storage time were more distinguishable in those samples. Pet owners evaluated samples for aroma, appearance and overall liking. Descriptive sensory analysis detected significant changes in oxidized-related sensory characteristics over storage time. However, the differences for CBPM samples were more pronounced and directional. The consumer study showed no differences in pet owners' acceptability for BMBM samples. However, the noticeable increase in aroma characteristics (rancid aroma 0.33-4.21) in CBPM samples over storage time did have a negative effect on consumer's liking (overall liking 5.52-4.95).

  19. DEVELOPMENT OF PRECIPITATED IRON FISCHER-TROPSCH CATALYSTS

    International Nuclear Information System (INIS)

    Bukur, Dragomir B.; Lang, X.; Chokkaram, S.; Nowicki, L.; Wei, G.; Ding, Y.; Reddy, B.; Xiao, S.

    1999-01-01

    Despite the current worldwide oil glut, the US will ultimately require large-scale production of liquid (transportation) fuels from coal. Slurry phase Fischer-Tropsch (F-T) technology, with its versatile product slate, may be expected to play a major role in production of transportation fuels via indirect coal liquefaction. Some of the F-T catalysts synthesized and tested at Texas A and M University under DOE Contract No. DE-AC22-89PC89868 were more active than any other known catalysts developed for maximizing production of high molecular weight hydrocarbons (waxes). The objectives of the present contract were to demonstrate repeatability of catalyst performance and reproducibility of preparation procedures of two of these catalysts on a laboratory scale. Improvements in the catalyst performance were attempted through the use of: (a) higher reaction pressure and gas space velocity to maximize the reactor productivity; (b) modifications in catalyst preparation steps; and (c) different pretreatment procedures. Repeatability of catalyst performance and reproducibility of catalyst synthesis procedure have been successfully demonstrated in stirred tank slurry reactor tests. Reactor space-time-yield was increased up to 48% by increasing reaction pressure from 1.48 MPa to 2.17 MPa, while maintaining the gas contact time and synthesis gas conversion at a constant value. Use of calcination temperatures above 300 C, additional CaO promoter, and/or potassium silicate as the source of potassium promoter, instead of potassium bicarbonate, did not result in improved catalyst performance. By using different catalyst activation procedures they were able to increase substantially the catalyst activity, while maintaining low methane and gaseous hydrocarbon selectivities. Catalyst productivity in runs SA-0946 and SA-2186 was 0.71 and 0.86 gHC/g-Fe/h, respectively, and this represents 45-75% improvement in productivity relative to that achieved in Rheinpreussen's demonstration plant

  20. Catalyst systems and uses thereof

    Science.gov (United States)

    Ozkan, Umit S [Worthington, OH; Holmgreen, Erik M [Columbus, OH; Yung, Matthew M [Columbus, OH

    2012-07-24

    A method of carbon monoxide (CO) removal comprises providing an oxidation catalyst comprising cobalt supported on an inorganic oxide. The method further comprises feeding a gaseous stream comprising CO, and oxygen (O.sub.2) to the catalyst system, and removing CO from the gaseous stream by oxidizing the CO to carbon dioxide (CO.sub.2) in the presence of the oxidation catalyst at a temperature between about 20 to about 200.degree. C.

  1. Highly Stable and Active Catalyst for Sabatier Reactions

    Science.gov (United States)

    Hu, Jianli; Brooks, Kriston P.

    2012-01-01

    Highly active Ru/TiO2 catalysts for Sabatier reaction have been developed. The catalysts have shown to be stable under repeated shutting down/startup conditions. When the Ru/TiO2 catalyst is coated on the engineered substrate Fe-CrAlY felt, activity enhancement is more than doubled when compared with an identically prepared engineered catalyst made from commercial Degussa catalyst. Also, bimetallic Ru-Rh/TiO2 catalysts show high activity at high throughput.

  2. Bioactive compounds and antioxidant capacity of extruded snack-type products developed from novel formulations of lentil and nutritional yeast flours.

    Science.gov (United States)

    Ciudad-Mulero, María; Barros, Lillian; Fernandes, Ângela; Berrios, José De J; Cámara, Montaña; Morales, Patricia; Fernández-Ruiz, Virginia; Ferreira, Isabel C F R

    2018-02-21

    Pulses are well known to be gluten-free functional foods that provide a rich source of nutritional and healthy compounds with antioxidant-promoting activity. In the present study, the bioactive compounds, dietary fibre, arabinoxylans, individual phenolic compounds and tocopherols, were evaluated in different lentil flours (raw and extruded at 140 and 160 °C) formulated with nutritional yeasts, along with the changes induced by the extrusion process. The total dietary fibre and arabinoxylan content significantly (p extruded lentil flours. The decreases of total phenolic and individual phenolic compounds were directly related to the extrusion temperature; total phenolics and catechin hexoside exhibited a larger decrease in the lentil flours formulated with higher content of nutritional yeast (12 and 16%). The antioxidant activity results, determined using different assays, reflected the important effect of extrusion processing and food ingredients.

  3. Efeito dos parâmetros de extrusão sobre as propriedades funcionais de extrusados da farinha de batata-doce Effect of extrusion parameters on sweet potato extrudates

    Directory of Open Access Journals (Sweden)

    Alexandra M. Borba

    2005-12-01

    Full Text Available Farinha de batata-doce (Ipomoea batatas foi extrusada em equipamento de rosca simples, mantendo-se fixas as temperaturas na 1ª e 2ª zonas de extrusão (20ºC e 60ºC, respectivamente. O efeito das variáveis umidade da farinha (15, 18 e 21%, temperatura na 3ª zona (100, 120 e 140ºC e rotação da rosca (180, 210 e 240 rpm sobre as características dos extrusados foi investigado utilizando-se metodologia de superfície de resposta. O teor de umidade e a temperatura de extrusão influenciaram significativamente a expansão dos extrusados. O índice de expansão apresentou valores crescentes com a temperatura sob baixos teores de umidade. A dureza dos extrusados e também o índice de absorção de água e o índice de solubilidade em água das farinhas extrusadas não mostraram modelo de regressão significativo com as condições de processo. Quanto à cor das farinhas, o componente L* (luminosidade apresentou valores crescentes e o parâmetro a*, valores decrescentes com a elevação do teor de umidade até 20-21%. O parâmetro b* e a diferença de cor entre farinhas extrusadas e não extrusadas mostraram valores decrescentes com o aumento da umidade.Sweet potato flour was processed using a single-screw extruder, with extrusion temperatures in zones 1 and 2 of 20ºC and 60ºC, respectively. The effect of flour moisture content (15, 18 and 21%, barrel temperature in zone 3 (100, 120 and 140ºC and screw speed (180, 210 and 240 rpm on extrudate attributes was investigated using response surface methodology. Moisture content and extrusion temperature had a significant (p<0.05 influence on extrudates expansion. The expansion ratio of the extrudates showed increasing values with temperature under conditions of low moisture content. The firmness of extrudates and also the water absorption index and water solubility index of the pre-gelatinized flours did not show significant regression models with the processing conditions. The flours color was

  4. Effect of storage on oxidative quality and stability of extruded astaxanthin-coated fish feed pellets

    DEFF Research Database (Denmark)

    Dethlefsen, Markus Wied; Hjermitslev, Niels Harthøj; Frosch, Stina

    2016-01-01

    This study examined the stability of extruded and astaxanthin-coated fish feed pellets during storage in a light box at 28°C and 620lx. Seven groups of fish feed pellets were vacuum coated with fish oil that contained levels of astaxanthin ranging from 0 to 100ppm. To equalize differences...... was comparatively protected against degradation. Furthermore, the initial concentrations of astaxanthin influenced the degradation per se, signifying self-protective properties of astaxanthin....

  5. The use of tubular retractors for translaminar discectomy for cranially and caudally extruded discs

    Directory of Open Access Journals (Sweden)

    Arvind G Kulkarni

    2018-01-01

    Full Text Available Background: The conventional interlaminar approach is adequate for access to most disc herniations in lumbar spine surgery. The access to cranially and caudally migrated disc fragments, by conventional interlaminar fenestration, requires an extension of the fenestration with the potential destruction of the facet joint complex and consequent postsurgical instability. To describe the technique and results of the translaminar technique of targeted discectomy using tubular retractors for the surgical treatment of cranially and caudally extruded discs. Materials and Methods: The study period extended from January 2008 to December 2014. All patients with lumbar herniated discs who failed conservative management were selected for surgery and underwent routine erect radiographs and magnetic resonance imaging (MRI of the lumbar spine. The patients with cranially or caudally migrated discs were included in this study. The technique involves approaching migrated disc through an oval window (sculpted through an 18 mm tubular retractor using a burr in the lamina precisely over the location of the migrated disc as predicted by the preoperative MRI (inferior lamina for inferior migration and superior lamina for superior migration. The perioperative parameters studied were operative time, blood loss, complications, Oswestry Disability Index (ODI, and visual analog scale (VAS for leg pain before surgery and at last followup. In the study, 4 patients underwent a postoperative computed tomography-scan with a three-dimensional reconstruction to visualize the oval window and to rule out any pars fracture. All technical difficulties and complications were analyzed. Results: 17 patients in the age group of 41–58 years underwent the translaminar technique of targeted discectomy. The migration of disc was cranial in 12 patients and caudal in 5 patients. Fourteen of the affected discs were at the L4–L5 level and three were at the L5-S1 level. The mean VAS (leg pain

  6. Reactivation of a tin oxide-containing catalyst

    Science.gov (United States)

    Upchurch, Billy T. (Inventor); Miller, Irvin M. (Inventor); Brown, Kenneth G. (Inventor); Hess, Robert V. (Inventor); Schryer, David R. (Inventor); Sidney, Barry D. (Inventor); Wood, George M. (Inventor); Paulin, Patricia A. (Inventor)

    1989-01-01

    A method for the reactivation of a tin oxide-containing catalyst of a CO.sub.2 laser is provided. First, the catalyst is pretreated by a standard procedure. When the catalyst experiences diminished activity during usage, the heated zone surrounding the catalyst is raised to a temperature which is the operating temperature of the laser and 400.degree. C. for approximately one hour. The catalyst is exposed to the same laser gas mixture during this period. The temperature of the heated zone is then lowered to the operating temperature of the CO.sub.2 laser.

  7. In situ Transmission Electron Microscopy of catalyst sintering

    DEFF Research Database (Denmark)

    DeLaRiva, Andrew T.; Hansen, Thomas Willum; Challa, Sivakumar R.

    2013-01-01

    Recent advancements in the field of electron microscopy, such as aberration correctors, have now been integrated into Environmental Transmission Electron Microscopes (TEMs), making it possible to study the behavior of supported metal catalysts under operating conditions at atomic resolution. Here......, we focus on in situ electron microscopy studies of catalysts that shed light on the mechanistic aspects of catalyst sintering. Catalyst sintering is an important mechanism for activity loss, especially for catalysts that operate at elevated temperatures. Literature from the past decade is reviewed...... along with our recent in situ TEM studies on the sintering of Ni/MgAl2O4 catalysts. These results suggest that the rapid loss of catalyst activity in the earliest stages of catalyst sintering could result from Ostwald ripening rather than through particle migration and coalescence. The smallest...

  8. Catalyst for hydrocarbon conversion

    International Nuclear Information System (INIS)

    Duhaut, P.; Miquel, J.

    1975-01-01

    A description is given for a catalyst and process for hydrocarbon conversions, e.g., reforming. The catalyst contains an alumina carrier, platinum, iridium, at least one metal selected from uranium, vanadium, and gallium, and optionally halogen in the form of metal halide of one of the aforesaid components. (U.S.)

  9. 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.

  10. 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...... the novel non-platinum metal catalyst material....

  11. Co-Assembled Supported Catalysts: Synthesis of Nano-Structured Supported Catalysts with Hierarchic Pores through Combined Flow and Radiation Induced Co-Assembled Nano-Reactors

    Directory of Open Access Journals (Sweden)

    Galip Akay

    2016-05-01

    Full Text Available A novel generic method of silica supported catalyst system generation from a fluid state is presented. The technique is based on the combined flow and radiation (such as microwave, thermal or UV induced co-assembly of the support and catalyst precursors forming nano-reactors, followed by catalyst precursor decomposition. The transformation from the precursor to supported catalyst oxide state can be controlled from a few seconds to several minutes. The resulting nano-structured micro-porous silica supported catalyst system has a surface area approaching 300 m2/g and X-ray Diffraction (XRD-based catalyst size controlled in the range of 1–10 nm in which the catalyst structure appears as lamellar sheets sandwiched between the catalyst support. These catalyst characteristics are dependent primarily on the processing history as well as the catalyst (Fe, Co and Ni studied when the catalyst/support molar ratio is typically 0.1–2. In addition, Ca, Mn and Cu were used as co-catalysts with Fe and Co in the evaluation of the mechanism of catalyst generation. Based on extensive XRD, Scanning Electron Microscopy (SEM and Transmission Electron Microscopy (TEM studies, the micro- and nano-structure of the catalyst system were evaluated. It was found that the catalyst and silica support form extensive 0.6–2 nm thick lamellar sheets of 10–100 nm planar dimensions. In these lamellae, the alternate silica support and catalyst layer appear in the form of a bar-code structure. When these lamellae structures pack, they form the walls of a micro-porous catalyst system which typically has a density of 0.2 g/cm3. A tentative mechanism of catalyst nano-structure formation is provided based on the rheology and fluid mechanics of the catalyst/support precursor fluid as well as co-assembly nano-reactor formation during processing. In order to achieve these structures and characteristics, catalyst support must be in the form of silane coated silica nano

  12. Processing and characterization of extruded breakfast meal formulated with broken rice and bean flour

    OpenAIRE

    Ana Vânia Carvalho; Rafaella de Andrade Mattietto; Priscila Zaczuk Bassinello; Selma Nakamoto Koakuzu; Alessandro de Oliveira Rios; Renan de Almeida Maciel; Rosangela Nunes Carvalho

    2012-01-01

    The objective of this work was to develop an extruded breakfast product containing broken rice and split old beans and to verify the influence of the extrusion process on their physicochemical, technological, and sensory characteristic. The final product had a protein content of 9.9 g.100 g-1, and therefore it can be considered a good source of proteins for children and teenagers. The dietary fiber content of the final edible product was 3.71 g.100 g-1. Therefore, the breakfast meal may be co...

  13. Conductometric method for determining water stability and nutrient leaching of extruded fish feed

    Directory of Open Access Journals (Sweden)

    Banjac Vojislav V.

    2017-01-01

    Full Text Available Water stability of eight samples of extruded salmon feeds was first determined by applying two gravimetric methods developed by the authors: gravimetric static and wet sieving method. Then, the conductometric method, primarily developed for investigation of nutrient leaching of feed into the water by the authors, was used for each sample. The aim of this study was to evaluate the potential of the conductometric measurement as a technique for determining water stability of extruded fish feed. In order to find any correlation between the results of two gravimetric tests and conductometric method, correlation analysis was employed. The results of static and wet sieving method were expressed as water stability index, which was expressed as the percent of remained dry matter of sample after being disintegrated in the water. The results of conductometric method were shown as conductivity curves for each sample, giving the insight in rate of nutrient leaching during the time. The obtained values of water conductivity showed no significant (p < 0.05 correlation with the results of static water method, while there was a negative significant (p < 0.05 correlation with the results of wet sieving method during first four hours of pellets soaking in water. The highest correlation coefficients were obtained within the first hour of conductivity measurement, demonstrating that proposed conductometric method had a potential to be applied as a rapid and simple method for determination and relative comparison of salmon feed water stability.[ Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III46012 and Grant no. TR31011

  14. Effects of amaranth addition on the pro-vitamin A content, and physical and antioxidant properties of extruded pro-vitamin A-biofortified maize snacks.

    Science.gov (United States)

    Beswa, Daniso; Dlamini, Nomusa R; Amonsou, Eric O; Siwela, Muthulisi; Derera, John

    2016-01-15

    Pro-vitamin A-biofortified maize snacks with added leafy vegetable may have a potential as nutritious and health-promoting products, especially in addressing vitamin A deficiency, which is prevalent in developing regions. The objective of the study was to determine the effects of adding amaranth leaf powder on the physical, antioxidant properties and pro-vitamin A content of extruded pro-vitamin A-biofortified maize snacks. Extruded snacks were processed using four pro-vitamin A-biofortified maize varieties that were composited with amaranth leaf powder at 0%, 1% and 3% (w/w) substitution levels. At higher amaranth concentration, the expansion ratio of the snacks decreased, while their hardness increased by as much as 93%. The physical quality of the snacks may therefore need improvement. As amaranth was increased, the phenolic content and antioxidant activity of the snacks increased as well as the pro-vitamin A content. Pro-vitamin A-biofortified maize with added amaranth has a potential for use in nutritious and healthy extruded snacks. There are limited studies reporting on processing pro-vitamin A maize with complementary plant foods, which is common with white maize in southern Africa; thus the current study serves as a baseline. © 2015 Society of Chemical Industry.

  15. exchanged Mg-Al hydrotalcite catalyst

    Indian Academy of Sciences (India)

    ) catalysts, ... The catalyst can be easily separated by simple filtration ... surface area by the single-point N2 adsorption method ... concentration of carbonate anions (by treating the cat- .... hydrotalcite phase along with copper hydroxide and.

  16. Two Catalysts for Selective Oxidation of Contaminant Gases

    Science.gov (United States)

    Wright, John D.

    2011-01-01

    Two catalysts for the selective oxidation of trace amounts of contaminant gases in air have been developed for use aboard the International Space Station. These catalysts might also be useful for reducing concentrations of fumes in terrestrial industrial facilities especially facilities that use halocarbons as solvents, refrigerant liquids, and foaming agents, as well as facilities that generate or utilize ammonia. The first catalyst is of the supported-precious-metal type. This catalyst is highly active for the oxidation of halocarbons, hydrocarbons, and oxygenates at low concentrations in air. This catalyst is more active for the oxidation of hydrocarbons and halocarbons than are competing catalysts developed in recent years. This catalyst completely converts these airborne contaminant gases to carbon dioxide, water, and mineral acids that can be easily removed from the air, and does not make any chlorine gas in the process. The catalyst is thermally stable and is not poisoned by chlorine or fluorine atoms produced on its surface during the destruction of a halocarbon. In addition, the catalyst can selectively oxidize ammonia to nitrogen at a temperature between 200 and 260 C, without making nitrogen oxides, which are toxic. The temperature of 260 C is higher than the operational temperature of any other precious-metal catalyst that can selectively oxidize ammonia. The purpose of the platinum in this catalyst is to oxidize hydrocarbons and to ensure that the oxidation of halocarbons goes to completion. However, the platinum exhibits little or no activity for initiating the destruction of halocarbons. Instead, the attack on the halocarbons is initiated by the support. The support also provides a high surface area for exposure of the platinum. Moreover, the support resists deactivation or destruction by halogens released during the destruction of halocarbons. The second catalyst is of the supported- metal-oxide type. This catalyst can selectively oxidize ammonia to

  17. Polyfunctional catalyst for processiing benzene fractions

    Energy Technology Data Exchange (ETDEWEB)

    G. Byakov; B.D. Zubitskii; B.G. Tryasunov; I.Ya. Petrov [Kuznetsk Basin State Technical University, Kemerovo (Russian Federation)

    2009-05-15

    A by-product of the coke industry is a raw benzene fraction benzene- 1 which may serve as for catalytic processes. The paper reports a study on the influence of the composition and temperatures on the activity and selectivity of NiO-V{sub 2}O{sub 6}-MoO{sub 3}/{gamma}-Al{sub 2}O{sub 3} catalysts and the corresponding binary and tertiary subsystems are studied by a pulse method in model reactions; the hydrodealkylating of toluene and the hydrodesulfurizing of thioprhene. The optimal catalyst composition is established. The new catalyst is compared with industrial catalysts.

  18. Extruded snacks with the addition of different fish meals

    Directory of Open Access Journals (Sweden)

    Elenice Souza dos Reis GOES

    2015-01-01

    Full Text Available Abstract Tilapia, salmon, tuna and sardine meals were prepared to develop and analyze extruded snacks with residue meal from fish processing. Residue meals were included in five types of corn snacks: control (0% fish meal and four with 9% tilapia, salmon, tuna and sardine meals. Although moisture, lipids and carbohydrates rates did not differ among the snacks, protein rates increased with the increment of fish meal, reaching 11.85% in the tuna snack. Tuna and sardine snacks had the highest iron levels. The most abundant fatty acids were linoleic, oleic, palmitic, linolenic and stearic acids, with sardine, salmon and tuna snacks presenting the highest values of n-3 series fatty acids. Greater luminosity rate was reported for salmon snack, followed by tilapia, tuna and sardine snacks. The highest sensory acceptance index was verified in tilapia (78.07% and salmon (72.40%. A 9% addition of residue meals of tilapia, salmon and tuna improved the nutritional value of the snacks.

  19. Calcium and lanthanum solid base catalysts for transesterification

    Science.gov (United States)

    Ng, K. Y. Simon; Yan, Shuli; Salley, Steven O.

    2015-07-28

    In one aspect, a heterogeneous catalyst comprises calcium hydroxide and lanthanum hydroxide, wherein the catalyst has a specific surface area of more than about 10 m.sup.2/g. In another aspect, a heterogeneous catalyst comprises a calcium compound and a lanthanum compound, wherein the catalyst has a specific surface area of more than about 10 m.sup.2/g, and a total basicity of about 13.6 mmol/g. In further another aspect, a heterogeneous catalyst comprises calcium oxide and lanthanum oxide, wherein the catalyst has a specific surface area of more than about 10 m.sup.2/g. In still another aspect, a process for preparing a catalyst comprises introducing a base precipitant, a neutral precipitant, and an acid precipitant to a solution comprising a first metal ion and a second metal ion to form a precipitate. The process further comprises calcining the precipitate to provide the catalyst.

  20. Creep behavior and threshold stress of an extruded Al-6Mg-2Sc-1Zr alloy

    International Nuclear Information System (INIS)

    Deshmukh, S.P.; Mishra, R.S.; Kendig, K.L.

    2004-01-01

    Creep experiments were performed on extruded Al-6Mg-2Sc-1Zr (wt.%) alloy in a temperature range of 423-533 K. A threshold type creep behavior was measured and explained by observed dislocation-particle interactions. The experimental threshold stress values at various temperatures were compared with existing theoretical models. None of the available models could account for the decrease in threshold creep strength with increasing temperature

  1. Water Susceptibility and Mechanical Properties of Thermoplastic Starch–Pectin Blends Reactively Extruded with Edible Citric Acid

    OpenAIRE

    Da Róz,Alessandra Luzia; Veiga-Santos,Pricila; Ferreira,Adriane Medeiros; Antunes,Thaís Cristina Ribeiro; Leite,Fabio de Lima; Yamaji,Fabio Minoru; Carvalho,Antonio José Felix de

    2016-01-01

    Pectin and starch are edible, non-toxic, biodegradable and obtained from renewable sources. Also, have the benefit to be easily cross-linked producing hydrogels. Reactive extrusion with edible citric acid and cross linking interactions was evaluated on extruded thermoplastic in natura and cationic starch-pectin blends. Materials water susceptibility and mechanical properties were characterised. Reactive extrusion decreased (up to 75% in natura starch) mechanical properties. Also have decrease...

  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. Effect of different calcium sources on the antioxidant stability of tortilla chips from extruded and nixtamalized blue corn (Zea mays L. flours

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Sánchez-Madrigal

    2014-03-01

    Full Text Available This research aimed to develop tortilla chips (TC high in antioxidants from extruded and nixtamalized blue corn flours prepared with calcium hydroxide Ca(OH2 and calcium lactate C6H10O6Ca. Tortilla chips were made with extruded flours [0.1% Ca(OH2; 0.9% C6H10O6Ca; without calcium] and nixtamalized flours [1% Ca(OH2; 2.95% C6H10O6Ca] using the frying process. Total anthocyanin, total phenolics content, antioxidant activity, color, texture, and oil content were determined. The color of tortilla chips from extruded flours (TCEF showed high values of the parameters a* and b* indicating a reduction in the blue color. These color parameters were significantly different from those observed in tortilla chips from nixtamalized flours (TCNF, which tended to be more blue. The TCEF retained 15% anthocyanins, 34% phenolics, and 54% antioxidant activity. Pearson's correlation analysis indicated that anthocyanins and phenolics correlated significantly with antioxidant activity and color. TCEF with both calcium sources showed higher fracturability compared with that of TCNF. Oil absorption showed an opposite effect, with lower oil content in TCEF. Nixtamalization and extrusion with C6H10O6Ca resulted in flours and TC high in anthocyanins and antioxidant activity, representing an alternative production process for corn snack high in antioxidants.

  4. Processing of nanocomposites EVA/PVC/MMT in twin-screw extruder

    International Nuclear Information System (INIS)

    Gehlen, A.; Barbutti Filho, W.R.; Francisquetti, E.L.; Andrade, M.Z.; Zattera, A.J.

    2010-01-01

    Polymeric nanocomposites have some superior properties when compared to conventional polymer composites and is one of the most promising fields in the nanotechnology research. In a EVA (ethylene vinyl acetate) /PVC (poly vinyl chloride) matrix was incorporated different types of montmorillonite clays (an inorganic (Na + ) and two organic modified (15A and 30B nanoclays). The mixtures were processed in a co-rotating twin-screw extruder at processing speeds of 200 and 400 rpm. Thermogravimetric analysis (TGA) shown that the inorganic and organic modified clays promoted a shift to higher temperatures in the degradation temperature., X-ray diffraction (XRD) and transmission electronic microscopy (TEM) shows a possible intercalation with the 15A clay, exfoliation with the 30B clay and formation of clusters in the Na + clay. For all clays studied, the increase in shear rate does not promote significant changes. (author)

  5. Novel anode catalyst for direct methanol fuel cells.

    Science.gov (United States)

    Basri, S; Kamarudin, S K; Daud, W R W; Yaakob, Z; Kadhum, A A H

    2014-01-01

    PtRu catalyst is a promising anodic catalyst for direct methanol fuel cells (DMFCs) but the slow reaction kinetics reduce the performance of DMFCs. Therefore, this study attempts to improve the performance of PtRu catalysts by adding nickel (Ni) and iron (Fe). Multiwalled carbon nanotubes (MWCNTs) are used to increase the active area of the catalyst and to improve the catalyst performance. Electrochemical analysis techniques, such as energy dispersive X-ray spectrometry (EDX), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS), are used to characterize the kinetic parameters of the hybrid catalyst. Cyclic voltammetry (CV) is used to investigate the effects of adding Fe and Ni to the catalyst on the reaction kinetics. Additionally, chronoamperometry (CA) tests were conducted to study the long-term performance of the catalyst for catalyzing the methanol oxidation reaction (MOR). The binding energies of the reactants and products are compared to determine the kinetics and potential surface energy for methanol oxidation. The FESEM analysis results indicate that well-dispersed nanoscale (2-5 nm) PtRu particles are formed on the MWCNTs. Finally, PtRuFeNi/MWCNT improves the reaction kinetics of anode catalysts for DMFCs and obtains a mass current of 31 A g(-1) catalyst.

  6. Long time experience with deactivation and regeneration of DENOX catalysts and evaluation with the Internet database LEONID; Langzeiterfahrung mit der Deaktivierung und Regeneration von DENOX-Katalysatoren sowie Auswertung mit der Internet-Datenbank LEONID

    Energy Technology Data Exchange (ETDEWEB)

    Brandenstein, J.; Dieckmann, H.J.; Gutberlet, H. [E.ON Engineering GmbH, Gelsenkirchen (Germany)

    2008-07-01

    The paper gives an overview over the long-term catalyst deactivation and the main reasons for catalyst aging. The chemical composition of de-activated catalysts provides information on the optimum catalyst regeneration process. The long-term deactivation behaviour of regenerated catalysts is compared to new catalysts. All characteristic catalyst features are listed in an online 'LEONID'-database, developed by E.ON Engineering. The database provides the basis for long-term catalyst management of all connected SCR systems. (orig.)

  7. Preparation, melting behavior and thermal stability of poly(lactic acid)/poly(propylene carbonate) blends processed by vane extruder

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Wei, E-mail: zw55624@163.com; Chen, Rongyuan; Zhang, Haichen; Qu, Jinping, E-mail: jpqu@scut.edu.cn [National Engineering Research Center of Novel Equipment for Polymer Processing, South China University of Technology, Guangzhou 510640 (China)

    2016-03-09

    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.

  8. Carbons and carbon supported catalysts in hydroprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, Edward

    2009-07-01

    This book is a comprehensive summary of recent research in the field and covers all areas of carbons and carbon materials. The potential application of carbon supports, particularly those of carbon black (CB) and activated carbon (AC) in hydroprocessing catalysis are covered. Novel carbon materials such as carbon fibers and carbon nano tubes (CNT) are also covered, including the more recent developments in the use of fullerenes in hydroprocessing applications. Although the primary focus of this book is on carbons and carbon supported catalysts, it also identifies the difference in the effect of carbon supports compared with the oxidic supports, particularly that of the Al{sub 2}O{sub 3}. The difference in catalyst activity and stability was estimated using both model compounds and real feeds under variable conditions. The conditions applied during the preparation of carbon supported catalysts are also comprehensively covered and include various methods of pretreatment of carbon supports to enhance catalyst performance. The model compounds results consistently show higher hydrodesulfurization and hydrodeoxygenation activities of carbon supported catalysts than that of the Al{sub 2}O{sub 3} supported catalysts. Also, the deactivation of the former catalysts by coke deposition was much less evident. Chapter 6.3.1.3 is on carbon-supported catalysts: coal-derived liquids.

  9. Optimization of catalyst system reaps economic benefits

    International Nuclear Information System (INIS)

    Le Roy, C.F.; Hanshaw, M.J.; Fischer, S.M.; Malik, T.; Kooiman, R.R.

    1991-01-01

    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

  10. 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.

  11. Method of performing sugar dehydration and catalyst treatment

    Science.gov (United States)

    Hu, Jianli [Kennewick, WA; Holladay, Johnathan E [Kennewick, WA; Zhang, Xinjie [Burlington, MA; Wang, Yong [Richland, WA

    2010-06-01

    The invention includes a method of treating a solid acid catalyst. After exposing the catalyst to a mixture containing a sugar alcohol, the catalyst is washed with an organic solvent and is then exposed to a second reaction mixture. The invention includes a process for production of anhydrosugar alcohol. A solid acid catalyst is provided to convert sugar alcohol in a first sample to an anhydrosugar alcohol. The catalyst is then washed with an organic solvent and is subsequently utilized to expose a second sample. The invention includes a method for selective production of an anhydrosugar. A solid acid catalyst is provided within a reactor and anhydrosugar alcohol is formed by flowing a starting sugar alcohol into the reactor. The acid catalyst is then exposed to an organic solvent which allows a greater amount of additional anhydrosugar to be produced than would occur without exposing the acid catalyst to the organic solvent.

  12. Catalysts for oxidation of mercury in flue gas

    Science.gov (United States)

    Granite, Evan J [Wexford, PA; Pennline, Henry W [Bethel Park, PA

    2010-08-17

    Two new classes of catalysts for the removal of heavy metal contaminants, especially mercury (Hg) from effluent gases. Both of these classes of catalysts are excellent absorbers of HCl and Cl.sub.2 present in effluent gases. This adsorption of oxidizing agents aids in the oxidation of heavy metal contaminants. The catalysts remove mercury by oxidizing the Hg into mercury (II) moieties. For one class of catalysts, the active component is selected from the group consisting of iridium (Ir) and iridum-platinum (Ir/Pt) alloys. The Ir and Ir/Pt alloy catalysts are especially corrosion resistant. For the other class of catalyst, the active component is partially combusted coal or "Thief" carbon impregnated with Cl.sub.2. Untreated Thief carbon catalyst can be self-activating in the presence of effluent gas streams. The Thief carbon catalyst is disposable by means of capture from the effluent gas stream in a particulate collection device (PCD).

  13. Biomass processing over gold catalysts

    CERN Document Server

    Simakova, Olga A; Murzin, Dmitry Yu

    2014-01-01

    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 derived from cellulose, hemicelluloses, and woody biomass extractives. Since gold catalysts possess high stability under oxidative conditions, selective oxidation reactions were discussed more thoroughly than other critical reactions such as partial hydrogenation, acetalization, and isomerization. The influence of reaction conditions, the role of the catalyst, and the advantages and disadvantages of using gold are pre...

  14. Palladium catalysts deposited on silica materials: Comparison of catalysts based on mesoporous and amorphous supports in Heck reaction

    Czech Academy of Sciences Publication Activity Database

    Demel, J.; Čejka, Jiří; Štěpnička, P.

    2010-01-01

    Roč. 329, 1-2 (2010), s. 13-20 ISSN 1381-1169 R&D Projects: GA ČR GA104/09/0561 Institutional research plan: CEZ:AV0Z40400503 Keywords : heterogeneous catalysts * immobolized catalysts * supported catalysts Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.872, year: 2010

  15. Structure and catalytic activity of regenerated spent hydrotreating catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Kim, C.S.; Massoth, F.E.; Furimsky, E. (Utah University, Salt Lake City, UT (USA). Dept. of Fuels Engineering)

    1992-11-01

    Two spent catalysts, obtained from different hydrodemetallation operations, were regenerated by two different treatments, viz. 2% (V/V) O[sub 2]/N[sub 2] and air. One spent catalyst (B), contained 3 wt% V and 15 wt% C, while the other (H) contained 10 wt% V, 14 wt% C and 8 wt% Fe. After regeneration in the O[sub 2]/N[sub 2] stream, catalyst B showed essentially complete recovery of its original surface area, whereas catalyst H showed only 70% recovery. Both catalysts showed substantial losses in surface area by the air treatment. Catalytic activity tests on the regenerated catalysts for hydrodesulfurization of thiophene and for hydrogenation of 1-hexene showed low recovery of activities, even for the regenerated catalyst in which the surface area had been completely recovered. X-ray diffraction analyses of the spent-regenerated catalysts revealed substantial changes in catalyst structure. Surface area and catalytic activity results were qualitatively explained by these catalyst structural changes. 17 refs., 1 fig., 3 tabs.

  16. The Dependence of CNT Aerogel Synthesis on Sulfur-driven Catalyst Nucleation Processes and a Critical Catalyst Particle Mass Concentration.

    Science.gov (United States)

    Hoecker, Christian; Smail, Fiona; Pick, Martin; Weller, Lee; Boies, Adam M

    2017-11-06

    The floating catalyst chemical vapor deposition (FC-CVD) process permits macro-scale assembly of nanoscale materials, enabling continuous production of carbon nanotube (CNT) aerogels. Despite the intensive research in the field, fundamental uncertainties remain regarding how catalyst particle dynamics within the system influence the CNT aerogel formation, thus limiting effective scale-up. While aerogel formation in FC-CVD reactors requires a catalyst (typically iron, Fe) and a promotor (typically sulfur, S), their synergistic roles are not fully understood. This paper presents a paradigm shift in the understanding of the role of S in the process with new experimental studies identifying that S lowers the nucleation barrier of the catalyst nanoparticles. Furthermore, CNT aerogel formation requires a critical threshold of Fe x C y  > 160 mg/m 3 , but is surprisingly independent of the initial catalyst diameter or number concentration. The robustness of the critical catalyst mass concentration principle is proved further by producing CNTs using alternative catalyst systems; Fe nanoparticles from a plasma spark generator and cobaltocene and nickelocene precursors. This finding provides evidence that low-cost and high throughput CNT aerogel routes may be achieved by decoupled and enhanced catalyst production and control, opening up new possibilities for large-scale CNT synthesis.

  17. Laboratory performance testing of an extruded bitumen containing a surrogate, sodium nitrate-based, low-level aqueous waste

    International Nuclear Information System (INIS)

    Mattus, A.J.; Kaczmarsky, M.M.

    1986-01-01

    Laboratory results of a comprehensive, regulatory performance test program, utilizing an extruded bitumen and a surrogate, sodium nitrate-based waste, have been compiled at the Oak Ridge National Laboratory (ORNL). Using a 53 millimeter, Werner and Pfleiderer extruder, operated by personnel of WasteChem Corporation of Paramus, New Jersey, laboratory-scale, molded samples of type three, 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, containing about 30 wt % sodium nitrate, in addition to eight heavy metals, cold cesium and strontium was utilized. Samples tested contained three levels of waste loading: that is, forty, fifty and sixty wt % salt. Performance test results include the ninety day 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 also include the unconfined compressive strength and surface morphology utilizing scanning electron microscopy. Data presented include correlations between waste form loading and test results, in addition to their relationship to regulatory performance requirements

  18. Extruded expanded polystyrene sheets coated by TiO{sub 2} as new photocatalytic materials for foodstuffs packaging

    Energy Technology Data Exchange (ETDEWEB)

    Loddo, V.; Marci, G. [Schiavello-Grillone Photocatalysis Group - Dipartimento di Ingegneria Elettrica, Elettronica e delle Telecomunicazioni, di tecnologie Chimiche, Automatica e modelli Matematici - Universita degli Studi di Palermo, Viale delle Scienze (Ed. 6) - 90128 Palermo (Italy); Palmisano, G., E-mail: giovanni_palmisano@yahoo.it [Schiavello-Grillone Photocatalysis Group - Dipartimento di Ingegneria Elettrica, Elettronica e delle Telecomunicazioni, di tecnologie Chimiche, Automatica e modelli Matematici - Universita degli Studi di Palermo, Viale delle Scienze (Ed. 6) - 90128 Palermo (Italy); Yurdakal, S. [Kimya Boeluemue, Fen-Edebiyat Fakueltesi, Afyon Kocatepe Ueniversitesi - Ahmet Necdet Sezer Kampuesue - 03200 Afyon (Turkey); Brazzoli, M.; Garavaglia, L. [Sirap-Gema S.p.A. - Via Industriale, 1/3 - 25028 Verolanuova (Brescia) (Italy); Palmisano, L., E-mail: leonardo.palmisano@unipa.it [Schiavello-Grillone Photocatalysis Group - Dipartimento di Ingegneria Elettrica, Elettronica e delle Telecomunicazioni, di tecnologie Chimiche, Automatica e modelli Matematici - Universita degli Studi di Palermo, Viale delle Scienze (Ed. 6) - 90128 Palermo (Italy)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer An extruded polystyrene has been functionalised by TiO{sub 2}. Black-Right-Pointing-Pointer A photocatalytic polymer has been developed via a sol-gel method. Black-Right-Pointing-Pointer Thermoformed packagings for foodstuffs application have been prepared. - Abstract: Nanostructured, photoactive anatase TiO{sub 2} sol prepared under very mild conditions using titanium tetraisopropoxide as the precursor is used to functionalise extruded expanded polystyrene (XPS) sheets by spray-coating resulting in stable and active materials functionalised by TiO{sub 2} nanoparticles. Photocatalytic tests of these sheets performed in a batch reactor in gas-solid system under UV irradiation show their successful activity in degrading probe molecules (2-propanol, trimethylamine and ethene). Raman spectra ensure the deposition of TiO{sub 2} as crystalline anatase phase on the polymer surface. The presence of TiO{sub 2} with respect to polymer surface can be observed in SEM images coupled to EDAX mapping allowing to monitor the surface morphology and the distribution of TiO{sub 2} particles. Finally thermoforming of these sheets in industrial standard equipment leads to useful containers for foodstuffs.

  19. Development of industrial hydrogenating catalyst on rhenium base

    International Nuclear Information System (INIS)

    Chistyakova, G.A.; Bat', I.I.; Rebrova, V.V.

    1975-01-01

    Processes for forming rhenium catalysts on carbon carrier and their catalytic properties in nitrobenzene (NB) reduction were studied. Application of an ammonia preparation to the carbon surface produced impregnated carbon saturated at room temperature with a water solution of the ammonia preparation, taken in a volume equal to the volumetric capacity of the carbon. With one impregnation, 2% rhenium was taken up. Catalysts containing more than 5% rhenium were obtained by impregnating the carbon with heating and use of more concentrated solutions. Catalysts made in this way and dried at 100 0 C had the composition Re 2 OH/carbon/. The most active catalysts were those reduced at 200-250 0 C; higher temperatures, up to 300-500 0 C, decreased the activity. Study of the catalytic properties of the rhenium catalysts in a liquid phase reduction of NB showed that the specific activity of rhenium depends only slightly on the content of the active component in the catalyst and is close to the specific activity of palladium and considerably exceeds that of nickel. Study of the effect of the NB concentration and hydrogen pressure on the activity and stability of the 5% rhenium catalyst indicated that with NB concentrations from 50 to 10% the process takes place at an essentially constant rate; the order of the reaction was close to zero with an apparent activation energy of about 7000 cal/mole. At pressures of 15-200 atm the yield with the 5% catalyst was proportional to the hydrogen pressure. A big advantage of the rhenium catalysts in the reduction of NB is their high selectivity. With a higher activity than palladium and nickel catalysts, 5% rhenium catalyst produces a high operating capacity in a wide range of contact charges, which has considerable significance for industrial use in contact apparatus of the column type. Comparison of the costs of rhenium catalysts and granular carbon carrier with those of nickel, platinum, and palladium showed that 5% rhenium catalyst can

  20. Reactivation of a Tin-Oxide-Containing Catalyst

    Science.gov (United States)

    Hess, Robert; Sidney, Barry; Schryer, David; Miller, Irvin; Miller, George; Upchurch, Bill; Davis, Patricia; Brown, Kenneth

    2010-01-01

    The electrons in electric-discharge CO2 lasers cause dissociation of some CO2 into O2 and CO, and attach themselves to electronegative molecules such as O2, forming negative O2 ions, as well as larger negative ion clusters by collisions with CO or other molecules. The decrease in CO2 concentration due to dissociation into CO and O2 will reduce the average repetitively pulsed or continuous wave laser power, even if no disruptive negative ion instabilities occur. Accordingly, it is the primary object of this invention to extend the lifetime of a catalyst used to combine the CO and O2 products formed in a laser discharge. A promising low-temperature catalyst for combining CO and O2 is platinum on tin oxide (Pt/SnO2). First, the catalyst is pretreated by a standard procedure. The pretreatment is considered complete when no measurable quantity of CO2 is given off by the catalyst. After this standard pretreatment, the catalyst is ready for its low-temperature use in the sealed, high-energy, pulsed CO2 laser. However, after about 3,000 minutes of operation, the activity of the catalyst begins to slowly diminish. When the catalyst experiences diminished activity during exposure to the circulating gas stream inside or external to the laser, the heated zone surrounding the catalyst is raised to a temperature between 100 and 400 C. A temperature of 225 C was experimentally found to provide an adequate temperature for reactivation. During this period, the catalyst is still exposed to the circulating gas inside or external to the laser. This constant heating and exposing the catalyst to the laser gas mixture is maintained for an hour. After heating and exposing for an appropriate amount of time, the heated zone around the catalyst is allowed to return to the nominal operating temperature of the CO2 laser. This temperature normally resides in the range of 23 to 100 C. Catalyst activity can be measured as the percentage conversion of CO to CO2. In the specific embodiment

  1. Platinum-Bismuth Bimetallic Catalysts: Synthesis, Characterization and Applications

    OpenAIRE

    Saucedo, Jose A, Jr; Xiao, Yang; Varma, Arvind

    2015-01-01

    Bimetallic catalysts have been explored and shown to exhibit unique characteristics which are not present in monometallic catalysts. Platinum is well known as an effective catalyst for oxidation and reduction reactions, and it can be made more effective when bismuth is introduced as a promotor. Thus, the effectiveness of the Pt-Bi catalyst was demonstrated in prior work. What is not clear, however, is the mechanism behind the catalyst function; why addition of bismuth to platinum decreases de...

  2. Effect of cysteine and cystine addition on sensory profile and potent odorants of extruded potato snacks.

    Science.gov (United States)

    Majcher, Małgorzata A; Jeleń, Henryk H

    2007-07-11

    Aromas generated in extruded potato snacks without and with addition of 0.25, 0.5, and 1% (w/w) of flavor precursors, cysteine and cystine, were compared and evaluated by descriptive sensory profiling. The results showed that high addition of cysteine (0.5 and 1%) resulted in the formation of undesirable odor and taste described as mercaptanic/sulfur, onion-like, and bitter; on the contrary, addition of cystine even at high concentration gave product with pleasant odor and taste, slightly changed into breadlike notes. GC/O analysis showed cysteine to be a much more reactive flavor precursor than cystine, stimulating formation of 12 compounds with garlic, sulfury, burnt, pungent/beer, cabbage/mold, meatlike, roasted, and popcorn odor notes. Further analysis performed by the AEDA technique identified 2-methyl-3-furanthiol (FD 2048) as a most potent odorant of extruded potato snacks with 1% addition of cysteine. Other identified compounds with high FD were butanal, 3-methyl-2-butenethiol, 2-methylthiazole, methional, 2-acetyl-1-pyrroline, and 3-hydroxy-4,5-dimethyl-2(5H)-furanone. In the case of cystine addition (1%) the highest FD factors were calculated for butanal, 2-acetyl-1-pyrroline, benzenemethanethiol, methional, phenylacetaldehyde, dimethyltrisulfide, 1-octen-3-ol, 1,5-octadien-3-one, and 2-acetylpyrazine.

  3. Polymer-bound rhodium hydroformylation catalysts

    NARCIS (Netherlands)

    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

  4. Catalyst design for carbon nanotube growth using atomistic modeling

    International Nuclear Information System (INIS)

    Pint, Cary L; Bozzolo, Guillermo; Hauge, Robert

    2008-01-01

    The formation and stability of bimetallic catalyst particles, in the framework of carbon nanotube growth, is studied using the Bozzolo-Ferrante-Smith (BFS) method for alloys. Monte Carlo-Metropolis simulations with the BFS method are utilized in order to predict and study equilibrium configurations for nanoscale catalyst particles which are directly relevant to the catalyst state prior to growth of carbon nanotubes. At the forefront of possible catalyst combinations is the popular Fe-Mo bimetallic catalyst, which we have recently studied experimentally. We explain our experimental results, which indicate that the growth observed is dependent on the order of co-catalyst deposition, in the straightforward interpretation of BFS strain and chemical energy contributions toward the formation of Fe-Mo catalyst prior to growth. We find that the competition between the formation of metastable inner Mo cores and clusters of surface-segregated Mo atoms in Fe-Mo catalyst particles influences catalyst formation, and we investigate the role of Mo concentration and catalyst particle size in this process. Finally, we apply the same modeling approach to other prominent bimetallic catalysts and suggest that this technique can be a powerful tool to understand and manipulate catalyst design for highly efficient carbon nanotube growth

  5. Novel Anode Catalyst for Direct Methanol Fuel Cells

    Directory of Open Access Journals (Sweden)

    S. Basri

    2014-01-01

    Full Text Available PtRu catalyst is a promising anodic catalyst for direct methanol fuel cells (DMFCs but the slow reaction kinetics reduce the performance of DMFCs. Therefore, this study attempts to improve the performance of PtRu catalysts by adding nickel (Ni and iron (Fe. Multiwalled carbon nanotubes (MWCNTs are used to increase the active area of the catalyst and to improve the catalyst performance. Electrochemical analysis techniques, such as energy dispersive X-ray spectrometry (EDX, X-ray diffraction (XRD, field emission scanning electron microscopy (FESEM, and X-ray photoelectron spectroscopy (XPS, are used to characterize the kinetic parameters of the hybrid catalyst. Cyclic voltammetry (CV is used to investigate the effects of adding Fe and Ni to the catalyst on the reaction kinetics. Additionally, chronoamperometry (CA tests were conducted to study the long-term performance of the catalyst for catalyzing the methanol oxidation reaction (MOR. The binding energies of the reactants and products are compared to determine the kinetics and potential surface energy for methanol oxidation. The FESEM analysis results indicate that well-dispersed nanoscale (2–5 nm PtRu particles are formed on the MWCNTs. Finally, PtRuFeNi/MWCNT improves the reaction kinetics of anode catalysts for DMFCs and obtains a mass current of 31 A g−1 catalyst.

  6. Immobilization of molecular catalysts in supported ionic liquid phases.

    Science.gov (United States)

    Van Doorslaer, Charlie; Wahlen, Joos; Mertens, Pascal; Binnemans, Koen; De Vos, Dirk

    2010-09-28

    In a supported ionic liquid phase (SILP) catalyst system, an ionic liquid (IL) film is immobilized on a high-surface area porous solid and a homogeneous catalyst is dissolved in this supported IL layer, thereby combining the attractive features of homogeneous catalysts with the benefits of heterogeneous catalysts. In this review reliable strategies for the immobilization of molecular catalysts in SILPs are surveyed. In the first part, general aspects concerning the application of SILP catalysts are presented, focusing on the type of catalyst, support, ionic liquid and reaction conditions. Secondly, organic reactions in which SILP technology is applied to improve the performance of homogeneous transition-metal catalysts are presented: hydroformylation, metathesis reactions, carbonylation, hydrogenation, hydroamination, coupling reactions and asymmetric reactions.

  7. 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

  8. Iridium-catalyst-based autonomous bubble-propelled graphene micromotors with ultralow catalyst loading.

    Science.gov (United States)

    Wang, Hong; Sofer, Zdeněk; Eng, Alex Yong Sheng; Pumera, Martin

    2014-11-10

    A novel concept of an iridium-based bubble-propelled Janus-particle-type graphene micromotor with very high surface area and with very low catalyst loading is described. The low loading of Ir catalyst (0.54 at %) allows for fast motion of graphene microparticles with high surface area of 316.2 m(2)  g(-1). The micromotor was prepared with a simple and scalable method by thermal exfoliation of iridium-doped graphite oxide precursor composite in hydrogen atmosphere. Oxygen bubbles generated from the decomposition of hydrogen peroxide at the iridium catalytic sites provide robust propulsion thrust for the graphene micromotor. The high surface area and low iridium catalyst loading of the bubble-propelled graphene motors offer great possibilities for dramatically enhanced cargo delivery. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Catalytic Transformation of Ethylbenzene over Y-Zeolite-based Catalysts

    KAUST Repository

    Al-Khattaf, Sulaiman

    2008-11-19

    Catalytic transformation of ethylbenzene (EB) has been investigated over ultrastable Y (USY)-zeolite-based catalysts in a novel riser simulator at different operating conditions. The effect of reaction conditions on EB conversion is reported. The USY catalyst (FCC-Y) was modified by steaming to form a significantly lower acidity catalyst (FCC-SY). The current study shows that the FCC-SY catalyst favors EB disproportionation more than cracking. A comparison has been made between the results of EB conversion over the lowly acidic catalyst (FCC-SY) and the highly acidic catalyst (FCC-Y) under identical conditions. It was observed that increase in catalyst acidity favored cracking of EB at the expense of disproportionation. Kinetic parameters for EB disappearance during disproportionation reaction over the FCC-SY catalyst were calculated using the catalyst activity decay function based on time on stream (TOS). © 2008 American Chemical Society.

  10. Efficient epoxidation of propene using molecular catalysts

    DEFF Research Database (Denmark)

    Markovits, Iulius I. E.; Anthofer, Michael H.; Kolding, Helene

    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...

  11. Multiphase catalysts for selective reduction of NOx with hydrocarbons

    International Nuclear Information System (INIS)

    Maisuls, S.E.

    2000-01-01

    Among the existing proposed solutions to reduce emission of NOx there is a promising alternative, the so-called (HC-SCR) selective catalytic reduction of NOx using hydrocarbons as reductant. This thesis is part of a worldwide effort devoted to gain knowledge on the selective catalytic reduction of NOx with hydrocarbons with the final goal to contribute to the development of suitable catalysts for the above mentioned process. Chapter 2 describes the details of the experimental set-up and of the analytical methods employed. Among the catalyst for HC-SCR, Co-based catalyst are known to be active and selective, thus, a study on a series of Co-based catalysts, supported on zeolites, was undertaken and the results are presented in Chapter 3. Correlation between catalytic characteristics and kinetic results are employed to understand the working catalyst and this is used as a basis for catalyst optimization. With the intention to prepare a multi-functional catalyst that will preserve the desired characteristics of the individual components, minimizing their negative aspects, catalysts based on Co-Pt, supported on ZSM-5, were investigated. In Chapter 4 the results of this study are discussed. A bimetallic Co-Pt/ZSM-5 catalysts with low Pt contents (0.1 wt %) showed a synergistic effect by combining high stability and activity of Pt catalysts with the high N2 selectivity of Co catalysts. Furthermore, it was found to be sulfur- and water-tolerant. Its positive qualities brought us to study the mechanism that takes place over this catalyst during HC-SCR. The results of an in-situ i.r mechanistic study over this catalyst is reported in Chapter 5. From the results presented in Chapter 5 a mechanism operating over the Co-Pt/ZSM-5 catalyst is proposed. The modification of Co catalyst with Pt improved the catalysts. However, further improvement was found to be hindered by high selectivity to N2O. Since Rh catalysts are generally less selective to N2O, the modification of Co

  12. Power generation in microbial fuel cells using platinum group metal-free cathode catalyst: Effect of the catalyst loading on performance and costs.

    Science.gov (United States)

    Santoro, Carlo; Kodali, Mounika; Herrera, Sergio; Serov, Alexey; Ieropoulos, Ioannis; Atanassov, Plamen

    2018-02-28

    Platinum group metal-free (PGM-free) catalyst with different loadings was investigated in air breathing electrodes microbial fuel cells (MFCs). Firstly, the electrocatalytic activity towards oxygen reduction reaction (ORR) of the catalyst was investigated by rotating ring disk electrode (RRDE) setup with different catalyst loadings. The results showed that higher loading led to an increased in the half wave potential and the limiting current and to a further decrease in the peroxide production. The electrons transferred also slightly increased with the catalyst loading up to the value of ≈3.75. This variation probably indicates that the catalyst investigated follow a 2x2e - transfer mechanism. The catalyst was integrated within activated carbon pellet-like air-breathing cathode in eight different loadings varying between 0.1 mgcm -2 and 10 mgcm -2 . Performance were enhanced gradually with the increase in catalyst content. Power densities varied between 90 ± 9 μWcm -2 and 262 ± 4 μWcm -2 with catalyst loading of 0.1 mgcm -2 and 10 mgcm -2 respectively. Cost assessments related to the catalyst performance are presented. An increase in catalyst utilization led to an increase in power generated with a substantial increase in the whole costs. Also a decrease in performance due to cathode/catalyst deterioration over time led to a further increase in the costs.

  13. Activating catalysts with mechanical force

    NARCIS (Netherlands)

    Piermattei, A.; Karthikeyan, S.; Sijbesma, R.P.

    2009-01-01

    Homogeneously catalysed reactions can be ‘switched on’ by activating latent catalysts. Usually, activation is brought about by heat or an external chemical agent. However, activation of homogeneous catalysts with a mechanical trigger has not been demonstrated. Here, we introduce a general method to

  14. Dearomatization of jet fuel on irradiated platinum-supported catalyst

    International Nuclear Information System (INIS)

    Mucka, V.; Ostrihonova, A.; Kopernicky, I.; Mikula, O.

    1983-01-01

    The effect of ionizing radiation ( 60 Co #betta#-rays) on Pt-supported catalyst used for the dearomatization of jet fuel with distillation in the range 395 to 534 K has been studied. Pre-irradiation of the catalyst with doses in the range 10 2 to 5 x 10 4 Gy leads to the partial catalyst activation. Irradiation of the catalyst enhances its resistance to catalyst poisons, particularly to sulphur-compounds, and this is probably the reason for its catalytic activity being approx. 60 to 100% greater than that of un-irradiated catalyst. Optimum conditions for dearomatization on the irradiated catalyst were found and, by means of a rotary three-factorial experiment, it was shown that these lie at lower temperatures and lower pressures than those for un-irradiated catalyst. (author)

  15. Multi-stage catalyst systems and uses thereof

    Science.gov (United States)

    Ozkan, Umit S [Worthington, OH; Holmgreen, Erik M [Columbus, OH; Yung, Matthew M [Columbus, OH

    2009-02-10

    Catalyst systems and methods provide benefits in reducing the content of nitrogen oxides in a gaseous stream containing nitric oxide (NO), hydrocarbons, carbon monoxide (CO), and oxygen (O.sub.2). The catalyst system comprises an oxidation catalyst comprising a first metal supported on a first inorganic oxide for catalyzing the oxidation of NO to nitrogen dioxide (NO.sub.2), and a reduction catalyst comprising a second metal supported on a second inorganic oxide for catalyzing the reduction of NO.sub.2 to nitrogen (N.sub.2).

  16. Process of activation of a palladium catalyst system

    Science.gov (United States)

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

    2011-08-02

    Improved processes for activating a catalyst system used for the reduction of nitrogen oxides are provided. In one embodiment, the catalyst system is activated by passing an activation gas stream having an amount of each of oxygen, water vapor, nitrogen oxides, and hydrogen over the catalyst system and increasing a temperature of the catalyst system to a temperature of at least 180.degree. C. at a heating rate of from 1-20.degree./min. Use of activation processes described herein leads to a catalyst system with superior NOx reduction capabilities.

  17. Characterization of catalysts by scanning transmission electron microscopy

    International Nuclear Information System (INIS)

    Targos, W.M.; Bradley, S.A.

    1989-01-01

    The dedicated scanning transmission electron microscope (STEM) is an integral tool for characterizing catalysts because of its unique ability to image and analyze nanosized volumes. This information is valuable in optimizing catalyst formulations and determining causes for reduced catalyst performance. For many commercial catalysts direct correlations between structural features of metal crystallites and catalytic performance are not attainable. When these instances occur, determination of elemental distribution may be the only information available. In this paper the authors discuss some of the techniques employed and limitations associated with characterizing commercial catalysts

  18. The interrupted properties of an extruded Mg alloy

    International Nuclear Information System (INIS)

    Xu, Shun; Liu, Tianmo; He, Jiejun; Lu, Liwei; Zeng, Wen

    2013-01-01

    Highlights: ► The reinforcement effect of {101 ¯ 2} twins on yield stress is reflected at low deformation. ► The recompressive yield stress equals to the stress when it is unloaded. ► The stress–strain curve of recompression seems like that without interruption. ► Twins generated in precompression could become thicker in recompression. -- Abstract: The current paper investigates the effect of {101 ¯ 2} extension twins identified by using electron backscattered diffraction on the interrupted properties of an extruded Mg–3Al–1Zn (AZ31) alloy. Compressive and recompressive tests are conducted along extrusion direction (ED). It is discovered that the yield strength of recompression is enhanced due to grain refinement by {101 ¯ 2} extension twins. The reinforcement effect of {101 ¯ 2} extension twins on the yield stress of recompression is mainly reflected at the stage of small deformation while the improvement of yield strength is mainly attributed to the pile-up and intersection of dislocations as large deformation occurs. Furthermore, the yield stress of recompression is identical to the interrupted stress of precompression. In situ observation reveals that some twins generated in precompression could also become thicker in the following recompression.

  19. DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    International Nuclear Information System (INIS)

    Adeyinka A. Adeyiga

    2001-01-01

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H 2 ) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. The use of iron-based catalysts is attractive not only due to their low cost and ready availability, but also due to their high water-gas shift activity which makes it possible to use these catalysts with low H 2 /CO ratios. However, a serious problem with use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, makes the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. Recently, fundamental understanding of physical attrition is being addressed by incorporating suitable binders into the catalyst recipe. This has resulted in the preparation of a spray dried Fe-based catalyst having aps of 70 mm with high attrition resistance. This Fe-based attrition resistant, active and selective catalyst gave 95% CO conversion through 125 hours of testing in a fixed-bed at 270 C, 1.48 MPa, H 2 /CO=0.67 and 2.0 NL/g-cat/h with C 5 + selectivity of >78% and methane selectivity of <5%. However, further development of the catalyst is needed to address the chemical attrition due to phase changes that any Fe-catalyst goes through potentially causing internal stresses within the particle and resulting in weakening, spalling or cracking. The objective of this research is to develop robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry bubble column reactor. Specifically we aim to develop to: (i) improve the performance and preparation procedure of the high activity, high attrition resistant, high alpha iron

  20. Catalysts and methods of using the same

    Energy Technology Data Exchange (ETDEWEB)

    Slowing, Igor Ivan; Kandel, Kapil

    2017-02-14

    The present invention provides a catalyst including a mesoporous silica nanoparticle and a catalytic material comprising iron. In various embodiments, the present invention provides methods of using and making the catalyst. In some examples, the catalyst can be used to hydrotreat fatty acids or to selectively remove fatty acids from feedstocks.

  1. Low platinum catalyst and method of preparation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Di-Jia; Chong, Lina

    2017-11-21

    A low platinum catalyst and method for making same. The catalyst comprises platinum-transition metal bimetallic alloy microcrystallites over a transition metal-nitrogen-carbon composite. A method of making a catalyst comprises preparation of transition metal organic frameworks, infusion of platinum, thermal treatment, and reduction to form the microcrystallites and composite.

  2. Chemical engineering design of CO oxidation catalysts

    Science.gov (United States)

    Herz, Richard K.

    1987-01-01

    How a chemical reaction engineer would approach the challenge of designing a CO oxidation catalyst for pulsed CO2 lasers is described. CO oxidation catalysts have a long history of application, of course, so it is instructive to first consider the special requirements of the laser application and then to compare them to the characteristics of existing processes which utilize CO oxidation catalysts. All CO2 laser applications require a CO oxidation catalyst with the following characteristics: (1) active at stoichiometric ratios of O2 and CO, (2) no inhibition by CO2 or other components of the laser environment, (3) releases no particulates during vibration or thermal cycling, and (4) long lifetime with a stable activity. In all applications, low consumption of power is desirable, a characteristic especially critical in aerospace applications and, thus, catalyst activity at low temperatures is highly desirable. High power lasers with high pulse repetition rates inherently require circulation of the gas mixture and this forced circulation is available for moving gas past the catalyst. Low repetition rate lasers, however, do not inherently require gas circulation, so a catalyst that did not require such circulation would be favorable from the standpoint of minimum power consumption. Lasers designed for atmospheric penetration of their infrared radiation utilize CO2 formed from rare isotopes of oxygen and this application has the additional constraint that normal abundance oxygen isotopes in the catalyst must not exchange with rare isotopes in the gas mixture.

  3. Roles of K2O on the CaO-ZnO Catalyst and Its Influence on Catalyst Basicity for Biodiesel Production

    Science.gov (United States)

    Buchori, Luqman; Istadi, I.; Purwanto; Marpaung, Louis Claudia; Safitri, Rahmatika Luthfiani

    2018-02-01

    This research aimed to study the effect of K2O impregnation on the basicity of the CaO-ZnO catalyst and its effect on biodiesel production. The effect of mole ratio of CaO to ZnO catalyst and %wt K2O were also studied. The mole ratio of CaO to ZnO catalyst was varied at 1:1, 1:1.5, 1:2, 1:3, and 3:1, while the %wt K2O was varied at 1, 3, and 5 %. The catalyst basicity was determined by titration method. The basicity of the catalyst increased after the CaO-ZnO catalyst was impregnated with K2O in all mole ratios of CaO-ZnO catalyst. The addition of K2O as a promoter also increase the basicity. The highest basicity was obtained at the CaO-ZnO mole ratio of 3:1 and 5%wt K2O. The tranesterification process was carried out in a batch reactor at a methanol to oil mole ratio of 15:1, a reaction temperature of 60°C, a reaction time of 4 h, and a catalyst loading of 5%wt oil. The FAME yields obtained were 41.33%. These results proved that K2O plays a role in enhancing the catalyst basicity. In addition, K2O also serves as a binding agent to improve the mechanical properties of the catalyst.

  4. Feasibility of Continuous Frying System to Improve the Quality Indices of Palm Olein for the Production of Extruded Product.

    Science.gov (United States)

    Ahmad Tarmizi, Azmil Haizam; Ahmad, Karimah

    2015-01-01

    Comparative frying studies on the processing of extruded product were conducted under intermittent and continuous frying conditions using two separate frying systems, i.e batch and pilot scale continuous fryers, respectively. Thermal resistance of palm olein were assessed for a total of 5 days of frying operation at 155°C - the unconventional frying temperature gave the product moisture content of 3% after intermittent and continuous frying for 2.5 min and 2 min, respectively. The formation of free fatty acid in palm olein in the case of intermittent frying was more than 2-fold higher compared to its counterpart (0.66%). Smoke point inversely evolved with oil acidity: the value dropped progressively from 215 to 177°C and from 219 to 188°C when extruded product was intermittently and continuously fried, respectively. In the light of induction period, repeated frying exhibited a gradual decrease in the value after 5 days of frying (12.2 h). Interestingly, continuous frying gave somewhat similar induction period, as demonstrated by fresh palm olein, across frying time. Frying at lower temperature, to some extent, provides opportunity for palm olein to retain 74% of its initial vitamin E during continuous frying. This benefit, however, is somehow denied when extruded product was processed under intermittent frying conditions--only 27% of vitamin E was remained at the end of frying session. Regardless of frying protocols, transient in polar compounds was minimal and hence comparable. The colour in the case of continuous frying appeared to be darker due to higher degree of oil utilisation for frying. The data obtained will provide useful information for food processors on how palm olein behaves when frying is undertaken under different frying protocols.

  5. Lunar CATALYST

    Data.gov (United States)

    National Aeronautics and Space Administration — Lunar Cargo Transportation and Landing by Soft Touchdown (Lunar CATALYST) is a NASA initiative to encourage the development of U.S. private-sector robotic lunar...

  6. Upscaling of a Batch De-Vulcanization Process for Ground Car Tire Rubber to a Continuous Process in a Twin Screw Extruder

    Directory of Open Access Journals (Sweden)

    Sitisaiyidah Saiwari

    2016-08-01

    Full Text Available As a means to decrease the amount of waste tires and to re-use tire rubber for new tires, devulcanization of ground passenger car tires is a promising process. Being an established process for NR and EPDM, earlier work has shown that for ground passenger car tire rubber with a relatively high amount of SBR, a devulcanization process can be formulated, as well. This was proven for a laboratory-scale batch process in an internal mixer, using diphenyl disulfide as the devulcanization aid and powder-sized material. In this paper, the devulcanization process for passenger car tire rubber is upscaled from 15 g per batch and transformed into a continuous process in a co-rotating twin screw extruder with a capacity of 2 kg/h. As SBR is rather sensitive to devulcanization process conditions, such as thermal and mechanical energy input, the screw design was based on a low shear concept. A granulate with particle sizes from 1–3.5 mm was chosen for purity, as well as economic reasons. The devulcanization process conditions were fine-tuned in terms of: devulcanization conditions (time/temperature profile, concentration of devulcanization aid, extruder parameters (screw configuration, screw speed, fill factor and ancillary equipment (pre-treatment, extrudate handling. The influence of these parameters on the devulcanization efficiency and the quality of the final product will be discussed. The ratio of random to crosslink scission as determined by a Horikx plot was taken for the evaluation of the process and material. A best practice for continuous devulcanization will be given.

  7. Study on microstructure and properties of extruded Mg-2Nd-0.2Zn alloy as potential biodegradable implant material.

    Science.gov (United States)

    Li, Junlei; Tan, Lili; Wan, Peng; Yu, Xiaoming; Yang, Ke

    2015-04-01

    Mg-2Nd-0.2Zn (NZ20) alloy was prepared for the application as biodegradable implant material in this study. The effects of the extrusion process on microstructure, mechanical and corrosion properties of the alloy were investigated. The as-cast alloy was composed of α-Mg matrix and Mg12Nd eutectic compound. The solution treatment could lead to the Mg12Nd phase dissolution and the grain coarsening. The alloy (E1) preheated at 380°C for 1h and extruded at 390°C presents fine grains with amounts of tiny Mg12Nd particles uniformly dispersed throughout the boundaries and the interior of the grains. The alloy (E2) preheated at 480°C for 1h and extruded at 500°C exhibits relatively larger grains with few nano-scale Mg12Nd phase particles dispersed. The alloy of E1, compared with E2, showed relatively lower corrosion rate, higher yield strength and slightly lower elongation. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Impact of dietary fibre-enriched ready-to-eat extruded snacks on the postprandial glycaemic response of non-diabetic patients.

    Science.gov (United States)

    Brennan, Margaret A; Derbyshire, Emma J; Brennan, Charles S; Tiwari, Brijesh K

    2012-05-01

    Food intervention is a financially sensible way for prevention and treatment of diabetes. Extruded snack foods are considered high glycaemic products. Our previous research illustrated that postprandial glycaemic responses to snacks are manipulated by altering dietary fibre and starch contents. The current research assessed the effect of psyllium and oat bran on postprandial glycaemia and in vitro digestibility. Addition of psyllium fibre to extruded snack products significantly reduced both the in vitro and in vivo glycaemic responses of products compared to a control snack product recipe. Oat bran inclusion reduced in vitro starch digestibility but not in vivo glycaemic response. The inclusion of oat bran into the snack products appeared to extend the glycaemic response of individuals compared to the control snack, suggesting a possibility of prolonging glucose release and potentially affecting satiety responses. The positive effect in attenuating glucose response means that psyllium fibre could be a target for inclusion by the snack food industry to effectively manipulate postprandial glucose response of individuals. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Bi-metallic catalysts, methods of making, and uses thereof

    KAUST Repository

    Basset, Jean-Marie

    2017-01-19

    Provided herein are bi-metallic catalysts, methods of making, and uses thereof. In some embodiments, the bi-metallic catalyst contains two different metal catalysts that can be used in hydrocarbon metathesis reactions, in some embodiments, the methods of making the bi-metallic catalysts can include two steps utilizing a surface organometallic chemistry approach in which the two different metal catalysts are sequentially grafted onto a support.

  10. Bi-metallic catalysts, methods of making, and uses thereof

    KAUST Repository

    Basset, Jean-Marie; Samantaray, Manoja K.; Dey, Raju; Abou-Hamad, Edy; Kavitake, Santosh

    2017-01-01

    Provided herein are bi-metallic catalysts, methods of making, and uses thereof. In some embodiments, the bi-metallic catalyst contains two different metal catalysts that can be used in hydrocarbon metathesis reactions, in some embodiments, the methods of making the bi-metallic catalysts can include two steps utilizing a surface organometallic chemistry approach in which the two different metal catalysts are sequentially grafted onto a support.

  11. Method of Heating a Foam-Based Catalyst Bed

    Science.gov (United States)

    Fortini, Arthur J.; Williams, Brian E.; McNeal, Shawn R.

    2009-01-01

    A method of heating a foam-based catalyst bed has been developed using silicon carbide as the catalyst support due to its readily accessible, high surface area that is oxidation-resistant and is electrically conductive. The foam support may be resistively heated by passing an electric current through it. This allows the catalyst bed to be heated directly, requiring less power to reach the desired temperature more quickly. Designed for heterogeneous catalysis, the method can be used by the petrochemical, chemical processing, and power-generating industries, as well as automotive catalytic converters. Catalyst beds must be heated to a light-off temperature before they catalyze the desired reactions. This typically is done by heating the assembly that contains the catalyst bed, which results in much of the power being wasted and/or lost to the surrounding environment. The catalyst bed is heated indirectly, thus requiring excessive power. With the electrically heated catalyst bed, virtually all of the power is used to heat the support, and only a small fraction is lost to the surroundings. Although the light-off temperature of most catalysts is only a few hundred degrees Celsius, the electrically heated foam is able to achieve temperatures of 1,200 C. Lower temperatures are achievable by supplying less electrical power to the foam. Furthermore, because of the foam s open-cell structure, the catalyst can be applied either directly to the foam ligaments or in the form of a catalyst- containing washcoat. This innovation would be very useful for heterogeneous catalysis where elevated temperatures are needed to drive the reaction.

  12. Pt/glassy carbon model catalysts prepared from PS-b-P2VP micellar templates.

    Science.gov (United States)

    Gu, Yunlong; St-Pierre, Jean; Ploehn, Harry J

    2008-11-04

    Poly(styrene)-block-poly(2-vinylpyridine) (PS-b-P2VP) diblock copolymer was used as a micellar template to fabricate arrays of Pt nanoparticles on mica and glassy carbon (GC) supports. Polymer micellar deposition yields Pt nanoparticles with tunable particle size and surface number density on both mica and GC. After deposition of precursor-loaded micelles onto GC, oxygen plasma etching removes the polymer shell, followed by thermal treatment with H2 gas to reduce the Pt. Etching conditions were optimized to maximize removal of the polymer while minimizing damage to the GC. Arrays of Pt nanoparticles with controlled size and surface number density can be prepared on mica (for particle size characterization) and GC to make Pt/GC model catalysts. These model catalysts were characterized by tapping mode atomic force microscopy, X-ray photoelectron spectroscopy, and cyclic voltammetry to measure activity for oxidation of carbon monoxide or methanol. Cyclic voltammetry results demonstrate the existence of a correlation between Pt particle size and electrocatalytic properties including onset potential, tolerance of carbonaceous adsorbates, and intrinsic activity (based on active Pt area from CO stripping voltammetry). Results obtained with Pt/GC model catalysts duplicate prior results obtained with Pt/porous carbon catalysts therefore validating the synthesis approach and offering a new, tunable platform to study catalyst structure and other effects such as aging on proton exchange membrane fuel cell (PEMFC) reactions.

  13. Encapsulated heterogeneous base catalysts onto SBA-15 nanoporous material as highly active catalysts in the transesterification of sunflower oil to biodiesel

    Science.gov (United States)

    Albayati, Talib M.; Doyle, Aidan M.

    2015-02-01

    Alkali metals and their hydroxides, Na, NaOH, Li, and LiOH, were encapsulated onto SBA-15 nanoporous material as highly active catalysts for the production of biodiesel fuel from sunflower oil. The incipient wetness impregnation method was adopted for the prepared catalysts. The characterization properties of the catalysts and unmodified SBA-15 were determined using X-ray diffraction, scanning electron microscopy, EDAX, nitrogen adsorption-desorption porosimetry (Brunauer-Emmett-Teller), Fourier-transform infrared spectroscopy, and transmission electron microscopy. Transesterification was conducted in a batch reactor at atmospheric pressure and 65 °C. The catalysts were highly active with yields of fatty acid methyl ester (FAME) in the range 96-99 %. Na/SBA-15 catalyst was reused for seven consecutive cycles under the same reaction conditions; the yield to FAME on the final cycle was 96 %. This study shows that the alkali metals and their hydroxides supported on SBA-15-based catalyst are excellent catalysts for the biodiesel reaction.

  14. Encapsulated heterogeneous base catalysts onto SBA-15 nanoporous material as highly active catalysts in the transesterification of sunflower oil to biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Albayati, Talib M., E-mail: talib-albyati@yahoo.com [University of Technology, Department of Chemical Engineering (Iraq); Doyle, Aidan M., E-mail: a.m.doyle@mmu.ac.uk [Manchester Metropolitan University, Division of Chemistry and Environmental Science (United Kingdom)

    2015-02-15

    Alkali metals and their hydroxides, Na, NaOH, Li, and LiOH, were encapsulated onto SBA-15 nanoporous material as highly active catalysts for the production of biodiesel fuel from sunflower oil. The incipient wetness impregnation method was adopted for the prepared catalysts. The characterization properties of the catalysts and unmodified SBA-15 were determined using X-ray diffraction, scanning electron microscopy, EDAX, nitrogen adsorption–desorption porosimetry (Brunauer–Emmett–Teller), Fourier-transform infrared spectroscopy, and transmission electron microscopy. Transesterification was conducted in a batch reactor at atmospheric pressure and 65 °C. The catalysts were highly active with yields of fatty acid methyl ester (FAME) in the range 96–99 %. Na/SBA-15 catalyst was reused for seven consecutive cycles under the same reaction conditions; the yield to FAME on the final cycle was 96 %. This study shows that the alkali metals and their hydroxides supported on SBA-15-based catalyst are excellent catalysts for the biodiesel reaction.

  15. Encapsulated heterogeneous base catalysts onto SBA-15 nanoporous material as highly active catalysts in the transesterification of sunflower oil to biodiesel

    International Nuclear Information System (INIS)

    Albayati, Talib M.; Doyle, Aidan M.

    2015-01-01

    Alkali metals and their hydroxides, Na, NaOH, Li, and LiOH, were encapsulated onto SBA-15 nanoporous material as highly active catalysts for the production of biodiesel fuel from sunflower oil. The incipient wetness impregnation method was adopted for the prepared catalysts. The characterization properties of the catalysts and unmodified SBA-15 were determined using X-ray diffraction, scanning electron microscopy, EDAX, nitrogen adsorption–desorption porosimetry (Brunauer–Emmett–Teller), Fourier-transform infrared spectroscopy, and transmission electron microscopy. Transesterification was conducted in a batch reactor at atmospheric pressure and 65 °C. The catalysts were highly active with yields of fatty acid methyl ester (FAME) in the range 96–99 %. Na/SBA-15 catalyst was reused for seven consecutive cycles under the same reaction conditions; the yield to FAME on the final cycle was 96 %. This study shows that the alkali metals and their hydroxides supported on SBA-15-based catalyst are excellent catalysts for the biodiesel reaction

  16. Nutritional value of raw and extruded chickpeas (Cicer arietinum L.) for growing chickens

    Energy Technology Data Exchange (ETDEWEB)

    Brenes, A.; Viveros, A.; Centeno, C.; Arija, I.; Marzo, F.

    2008-07-01

    The effects of the inclusion of different concentrations (0, 100, 200 and 300 g kg-1) of raw and extruded chickpeas on performance, digestive organ sizes, and protein and fat digestibilities were studied in one experiment with growing broiler chickens (0 to 21 days of age). Data were analyzed as a 3 x 2 factorial arrangement with three levels of chickpea with or without extrusion. A corn-soybean based diet was used as a positive control. Increasing chickpea content in the diet did not affect weight gain, feed consumption and feed to gain ratio. Relative pancreas and liver weights, and relative lengths of duodenum, jejunum and ceca were significantly (P<0.05) increased in response to increasing chickpea concentration in the diet. The inclusion of graded concentrations of chickpea increased (P<0.05) the apparent ileal digestibility (AID) of crude protein (CP) and apparent excreta digestibility (AED) of crude fat (CF) only in the case of the intermediate level of chickpea used (200 g kg-1). Extrusion improved weight gain and lowered relative pancreas weight (P< 0.05) respect to birds fed raw chickpea-based diets. AID of CP and AED of CF were improved (P<0.001) by extrusion. We concluded that the inclusion of up to 300 g kg-1 chickpea in chicken diets did not affect performance, and caused a negative effect on the relative weight of some digestive organs. (Author) 45 refs.

  17. Catalyst study for the plasma exhaust purification process

    International Nuclear Information System (INIS)

    Chabot, J.; Sannier, J.

    1990-01-01

    Several catalysts available from commercial sources have been screened to find out specific catalysts which allow complete methane oxidation and ammonia decomposition at temperature as low as possible in order to minimize tritium loss by permeation through processing equipment walls. Afterwards, an extended kinetic investigation has been performed on the best catalysts to achieve the data necessary to unit calculations. For methane oxidation, a palladium on alumina catalyst shows a very satisfactory low-temperature efficiency while a non-precious metal catalyst made of nickel oxide and alumina was found to be the more efficient for ammonia decomposition

  18. Attrition resistant Fischer-Tropsch catalyst and support

    Science.gov (United States)

    Singleton, Alan H.; Oukaci, Rachid; Goodwin, James G.

    2004-05-25

    A catalyst support having improved attrition resistance and a catalyst produced therefrom. The catalyst support is produced by a method comprising the step of treating calcined .gamma.-alumina having no catalytic material added thereto with an acidic aqueous solution having an acidity level effective for increasing the attrition resistance of the calcined .gamma.-alumina.

  19. Alkali resistivity of Cu based selective catalytic reduction catalysts

    DEFF Research Database (Denmark)

    Putluru, Siva Sankar Reddy; Jensen, Anker Degn; Riisager, Anders

    2012-01-01

    The deactivation of V2O5–WO3–TiO2, Cu–HZSM5 and Cu–HMOR plate type monolithic catalysts was investigated when exposed to KCl aerosols in a bench-scale reactor. Fresh and exposed catalysts were characterized by selective catalytic reduction (SCR) activity measurements, scanning electron microscope......–energy dispersive X-ray spectroscopy (SEM–EDX) and NH3-temperature programmed desorption (NH3-TPD). 95% deactivation was observed for the V2O5–WO3–TiO2 catalyst, while the Cu–HZSM5 and Cu–HMOR catalysts deactivated only 58% and 48%, respectively, after 1200 h KCl exposure. SEM analysis of the KCl aerosol exposed...... catalysts revealed that the potassium salt not only deposited on the catalyst surface, but also penetrated into the catalyst wall. Thus, the K/M ratio (M = V or Cu) was high on V2O5–WO3–TiO2 catalyst and comparatively less on Cu–HZSM5 and Cu–HMOR catalysts. NH3-TPD revealed that the KCl exposed Cu–HZSM5...

  20. Attrition Resistant Fischer-Tropsch Catalysts Based on FCC Supports

    Energy Technology Data Exchange (ETDEWEB)

    Adeyiga, Adeyinka

    2010-02-05

    Commercial spent fluid catalytic cracking (FCC) catalysts provided by Engelhard and Albemarle were used as supports for Fe-based catalysts with the goal of improving the attrition resistance of typical F-T catalysts. Catalysts with the Ruhrchemie composition (100 Fe/5 Cu/4.2 K/25 spent FCC on mass basis) were prepared by wet impregnation. XRD and XANES analysis showed the presence of Fe{sub 2}O{sub 3} in calcined catalysts. FeC{sub x} and Fe{sub 3}O{sub 4} were present in the activated catalysts. The metal composition of the catalysts was analyzed by ICP-MS. F-T activity of the catalysts activated in situ in CO at the same conditions as used prior to the attrition tests was measured using a fixed bed reactor at T = 573 K, P = 1.38 MPa and H{sub 2}:CO ratio of 0.67. Cu and K promoted Fe supported over Engelhard provided spent FCC catalyst shows relatively good attrition resistance (8.2 wt% fines lost), high CO conversion (81%) and C{sub 5}+ hydrocarbons selectivity (18.3%).

  1. Bio-oil hydrodeoxygenation catalysts produced using strong electrostatic adsorption

    Science.gov (United States)

    We synthesized hydrothermally stable metal catalysts with controlled particle size and distribution, with the goal of determining which catalyst(s) can selectively catalyze the production of aromatics from bio-oil (from pyrolysis of biomass). Both precious and base transition metal catalysts (Ru, Pt...

  2. Corrigendum to 'On the influence of microstructure on the fracture behaviour of hot extruded ferritic ODS steels' [J. Nucl. Mater. 497 (2017) 60-75

    Science.gov (United States)

    Das, A.; Viehrig, H. W.; Altstadt, E.; Heintze, C.; Hoffmann, J.

    2018-02-01

    ODS steels are known to show inferior fracture properties as compared to ferritic martensitic non-ODS steels. Hot extruded 13Cr ODS steel however, showed excellent fracture toughness at a temperature range from room temperature to 400 °C. In this work, the factors which resulted in superior and anisotropic fracture behaviour were investigated by comparing different orientations of two hot extruded materials using scanning electron, electron backscatter and transmission electron microscopy. Fracture behaviour of the two materials was compared using unloading compliance fracture toughness tests. Anisotropic fracture toughness was predominantly influenced by grain morphology. Superior fracture toughness in 13Cr ODS-KIT was predominantly influenced by factors such as smaller void inducing particle size and higher sub-micron particle-matrix interfacial strength.

  3. Enhancement of alkylation catalysts for improved supercritical fluid regeneration

    Science.gov (United States)

    Ginosar, Daniel M.; Petkovic, Lucia M.

    2010-12-28

    A method of modifying an alkylation catalyst to reduce the formation of condensed hydrocarbon species thereon. The method comprises providing an alkylation catalyst comprising a plurality of active sites. The plurality of active sites on the alkylation catalyst may include a plurality of weakly acidic active sites, intermediate acidity active sites, and strongly acidic active sites. A base is adsorbed to a portion of the plurality of active sites, such as the strongly acidic active sites, selectively poisoning the strongly acidic active sites. A method of modifying the alkylation catalyst by providing an alkylation catalyst comprising a pore size distribution that sterically constrains formation of the condensed hydrocarbon species on the alkylation catalyst or by synthesizing the alkylation catalyst to comprise a decreased number of strongly acidic active sites is also disclosed, as is a method of improving a regeneration efficiency of the alkylation catalyst.

  4. Characterization of Extruded Poly(lactic acid/Pecan Nutshell Biocomposites

    Directory of Open Access Journals (Sweden)

    C. R. Álvarez-Chávez

    2017-01-01

    Full Text Available Pecan nutshells are a solid form of waste obtained from the pecan nut production and they have been explored as an inexpensive filler for incorporation by melt blending into the poly(lactic acid (PLA matrix. The pecan nutshells contain polyphenols, proteins, tannins, sugars, and lipids; some of these components must be released in order to improve adhesion with a polymeric matrix. The physicochemical characterization of the extruded biocomposites of pecan nutshell powder (PNSP at 0, 5, and 7.5% wt. with two treatments (untreated and defatted into PLA is presented in this work. The incorporation of PNSP into the PLA matrix caused a variation in color and density and increased the water absorption. However, some mechanical and thermal parameters of the biocomposites showed a significant decrease. The morphological analysis showed good dispersion and adhesion of the PNSP to the PLA matrix. Based on the results of the characterization, biocomposites formulated with defatted PNSP have a potential to be used as sustainable fillers in PLA biocomposites. These biocomposites have a potential application as food containers, packaging trays, or disposable items.

  5. 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.

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

    International Nuclear Information System (INIS)

    May, A.; Taleb, L.; Belouchrani, M.A.

    2013-01-01

    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

  7. Molecular catalysts structure and functional design

    CERN Document Server

    Gade, Lutz H

    2014-01-01

    Highlighting the key aspects and latest advances in the rapidly developing field of molecular catalysis, this book covers new strategies to investigate reaction mechanisms, the enhancement of the catalysts' selectivity and efficiency, as well as the rational design of well-defined molecular catalysts. The interdisciplinary author team with an excellent reputation within the community discusses experimental and theoretical studies, along with examples of improved catalysts, and their application in organic synthesis, biocatalysis, and supported organometallic catalysis. As a result, readers wil

  8. Oxidation catalysts on alkaline earth supports

    Science.gov (United States)

    Mohajeri, Nahid

    2017-03-21

    An oxidation catalyst includes a support including particles of an alkaline earth salt, and first particles including a palladium compound on the support. The oxidation catalyst can also include precious metal group (PMG) metal particles in addition to the first particles intermixed together on the support. A gas permeable polymer that provides a continuous phase can completely encapsulate the particles and the support. The oxidation catalyst may be used as a gas sensor, where the first particles are chemochromic particles.

  9. Zircon Supported Copper Catalysts for the Steam Reforming of Methanol

    Science.gov (United States)

    Widiastri, M.; Fendy, Marsih, I. N.

    2008-03-01

    Steam reforming of methanol (SRM) is known as one of the most favorable catalytic processes for producing hydrogen. Current research on zirconia, ZrO2 supported copper catalyst revealed that CuO/ZrO2 as an active catalyst for the SRM. Zircon, ZrSiO4 is available from the by-product of tin mining. In the work presented here, the catalytic properties of CuO/ZrSiO4 with various copper oxide compositions ranging from 2.70% (catalyst I), 4.12% (catalyst II), and 7.12%-mass (catalyst III), synthesized by an incipient wetness impregnation technique, were investigated to methanol conversion, selectivity towards CO formation, and effect of ZnO addition (7.83%CuO/8.01%ZnO/ZrSiO4 = catalyst V). The catalytic activity was obtained using a fixed bed reactor and the zircon supported catalyst activity was compared to those of CuO/ZnO/Al2O3 catalyst (catalyst IV) and commercial Kujang LTSC catalyst. An X-ray powder diffraction (XRD) analysis was done to identify the abundant phases of the catalysts. The catalysts topography and particle diameter were measured with scanning electron microscopy (SEM) and composition of the catalysts was measured by SEM-EDX, scanning electron microscope-energy dispersive using X-ray analysis. The results of this research provide information on the possibility of using zircon (ZrSiO4) as solid support for SRM catalysts.

  10. Tritium transfer process using the CRNL wetproof catalyst

    International Nuclear Information System (INIS)

    Chuang, K.T.; Holtslander, W.J.

    1980-01-01

    The recovery of tritium from heavy water in CANDU reactor systems requires the transfer of the tritium atoms from water to hydrogen molecules prior to tritium concentration by cryogenic distillation. Isotopic exchange between liquid water and hydrogen using the CRNL-developed wetproof catalyst provides an effective method for the tritium transfer process. The development of this process has required the translation of the technology from a laboratory demonstration of catalyst activity for the exchange reaction to proving and demonstration that the process will meet the practical restraints in a full-scale tritium recovery plant. This has led to a program to demonstrate acceptable performance of the catalyst at operating conditions that will provide data for design of large plants. Laboratory and pilot plant work has shown adequate catalyst lifetimes, demonstrated catalyst regeneration techniques and defined and required feedwater purification systems to ensure optimum catalyst performance. The ability of the catalyst to promote the exchange of hydrogen isotopes between water and hydrogen has been shown to be technically feasible for the tritium transfer process

  11. Diethyl Ether Production Process with Various Catalyst Type

    Directory of Open Access Journals (Sweden)

    Widayat Widayat

    2012-12-01

    Full Text Available Several H-zeolite and HZSM-5 catalysts was preparated and their characters have also been investigated. H-zeolit Catalyst was preparated from Natural Zeolite that obtained from Malang District and Gunung Kidul District. Diethyl ether was produced by Ethanol with concentration of 95%. This research use fixed bed reactor that 1 gram of catalyst as bed catalyst, atmospheric pressure and temperature 140oC as the operating condition. Ethanol vapor from vaporization tank was driven by 200 ml/min Nitrogen stream. The responds in this research is liquid product concentration; diethyl ether, ethanol, methanol and water concentration. The results showed that the largest ethanol conversion was produced by the use of 56.44% HZSM-5 and the largest yield of diethyl ether diethyl was produced by the use of alumina and H-zeolite catalyst. The larger ratio between natural zeolite with HCl solvent will produce the larger surface area of catalyst and ethanol conversion. The largest ethanol conversion was produced at reactan ratio 1:20. [Keywords:  catalyst; ethanol conversion; dehydration process; yield of diethyl ether; natural zeolite].

  12. Micelle-derived catalysts for extended Schulz-Flory

    Energy Technology Data Exchange (ETDEWEB)

    Abrevaya, H.

    1986-01-01

    The objective of this program is to develop a synthesis gas conversion catalyst with higher selectivity to liquid fuels, while maintaining catalytic activity and stability at least equivalent relative to state-of-the-art precipitated iron catalysts. During this quarter, the emphasis in the program has been the investigation of the hydrocarbon cutoff hypothesis with supported ruthenium catalysts. An alumina-supported catalyst with smaller than 20[Angstrom] ruthenium particles was tested under conditions of maximal water gas shift activity. During this test more than 90% of the water made in the Fischer-Tropsch synthesis reaction was converted to H[sub 2]. However, the extent of ruthenium metal agglomeration was not reduced. Accordingly, it was not possible to conclude whether hydrocarbon cutoff occurs with smaller than 20[Angstrom] ruthenium particles on [gamma]-alumina. A ruthenium catalyst prepared on Y-type zeolite had 20[Angstrom] or smaller ruthenium particles according to STEM examination and a 15[Angstrom] average ruthenium metal particle size according to EXAFS examination. The ruthenium metal particle size was stable during the test with this catalyst. The hydrocarbon product distribution was Anderson-Schulz-Flory with no cutoff up to a carbon number of 160. A well-dispersed titania-supported ruthenium catalyst is going to be evaluated during the next quarter in order to determine whether hydrocarbon cutoff occurs.

  13. Reclaim/recycle of Pt/C catalysts for PEMFC

    International Nuclear Information System (INIS)

    Zhao, Jishi; He, Xiangming; Tian, Jianhua; Wan, Chunrong; Jiang, Changyin

    2007-01-01

    Platinum was reclaimed from Pt/C catalysts of the PEMFC by drying the degraded Pt/C catalysts at 80 o C for 3 h, followed by sintering at 600 o C for 6 h, dissolution by aqua fortis, purification with hydrochloric acid, reduction and filtration, successively. Pt/C catalysts were prepared again from the reclaimed Pt by two proposed processes, e.g., pH value control process and mass control process. The fuel cell with recycled catalysts presented a power density of over 0.18 W cm -2 . The reclaiming of Pt/C catalysts is a potential way for recycling Pt for PEMFC, reducing the cost of PEMFC

  14. Oxidative desulfurization of benzothiophene and thiophene with WOx/ZrO2 catalysts: effect of calcination temperature of catalysts.

    Science.gov (United States)

    Hasan, Zubair; Jeon, Jaewoo; Jhung, Sung Hwa

    2012-02-29

    Oxidative desulfurization (ODS) of model fuel containing benzothiophene (BT) or thiophene (Th) has been carried out with WO(x)/ZrO2 catalyst, which was calcined at various temperatures. Based on the conversion of BT in the model fuel, it can be shown that the optimum calcination temperature of WOx/ZrO2 catalyst is around 700 °C. The most active catalyst is composed of tetragonal zirconia (ZrO2) with well dispersed polyoxotungstate species and it is necessary to minimize the contents of the crystalline WO3 and monoclinic ZrO2 for a high BT conversion. The oxidation rate was interpreted with the first-order kinetics, and it demonstrated the importance of electron density since the kinetic constant for BT was higher than that for Th even though the BT is larger than Th in size. A WOx/ZrO2 catalyst, treated suitably, can be used as a reusable active catalyst in the ODS. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. 40 CFR 90.427 - Catalyst thermal stress resistance evaluation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Catalyst thermal stress resistance... Gaseous Exhaust Test Procedures § 90.427 Catalyst thermal stress resistance evaluation. (a) The purpose of... catalyst conversion efficiency for Phase 1 engines. The thermal stress is imposed on the test catalyst by...

  16. Tethered catalysts for the hydration of carbon dioxide

    Science.gov (United States)

    Valdez, Carlos A; Satcher, Jr., Joe H; Aines, Roger D; Wong, Sergio E; Baker, Sarah E; Lightstone, Felice C; Stolaroff, Joshuah K

    2014-11-04

    A system is provided that substantially increases the efficiency of CO.sub.2 capture and removal by positioning a catalyst within an optimal distance from the air-liquid interface. The catalyst is positioned within the layer determined to be the highest concentration of carbon dioxide. A hydrophobic tether is attached to the catalyst and the hydrophobic tether modulates the position of the catalyst within the liquid layer containing the highest concentration of carbon dioxide.

  17. A regionally-linked, dynamic material flow modelling tool for rolled, extruded and cast aluminium products

    DEFF Research Database (Denmark)

    Bertram, M.; Ramkumar, S.; Rechberger, H.

    2017-01-01

    A global aluminium flow modelling tool, comprising nine trade linked regions, namely China, Europe, Japan, Middle East, North America, Other Asia, Other Producing Countries, South America and Rest of World, has been developed. The purpose of the Microsoft Excel-based tool is the quantification...... of regional stocks and flows of rolled, extruded and casting alloys across space and over time, giving the industry the ability to evaluate the potential to recycle aluminium scrap most efficiently. The International Aluminium Institute will update the tool annually and publish a visualisation of results...

  18. CATALYSTS NHI Thermochemical Systems FY 2009 Year-End Report

    International Nuclear Information System (INIS)

    Ginosar, Daniel M.

    2009-01-01

    Fiscal Year 2009 work in the Catalysts project focused on advanced catalysts for the decomposition of sulfuric acid, a reaction common to both the Sulfur-Iodine (S-I) cycle and the Hybrid Sulfur cycle. Prior years effort in this project has found that although platinum supported on titanium oxide will be an acceptable catalyst for sulfuric acid decomposition in the integrated laboratory scale (ILS) project, the material has short comings, including significant cost and high deactivation rates due to sintering and platinum evaporation. For pilot and larger scale systems, the catalyst stability needs to be improved significantly. In Fiscal Year 2008 it was found that at atmospheric pressure, deactivation rates of a 1 wt% platinum catalyst could be reduced by 300% by adding either 0.3 wt% iridium (Ir) or 0.3 wt% ruthenium (Ru) to the catalyst. In Fiscal Year 2009, work focused on examining the platinum group metal catalysts activity and stability at elevated pressures. In addition, simple and complex metal oxides are known to catalyze the sulfuric acid decomposition reaction. These metal oxides could offer activities comparable to platinum but at significantly reduced cost. Thus a second focus for Fiscal Year 2009 was to explore metal oxide catalysts for the sulfuric acid decomposition reaction. In Fiscal Year 2007 several commercial activated carbons had been identified for the HI decomposition reaction; a reaction specific to the S-I cycle. Those materials should be acceptable for the pilot scale project. The activated carbon catalysts have some disadvantages including low activity at the lower range of reactor operating temperature (350 to 400 C) and a propensity to generate carbon monoxide in the presence of water that could contaminate the hydrogen product, but due to limited funding, this area had low priority in Fiscal Year 2009. Fiscal Year 2009 catalyst work included five tasks: development, and testing of stabilized platinum based H2SO4 catalysts

  19. Mordenite - Type Zeolite SCR Catalysts with Iron or Copper

    DEFF Research Database (Denmark)

    2012-01-01

    Cu/mordenite catalysts were found to be highly active for the SCR of NO with NH3 and exhibited high resistance to alkali poisoning. Redox and acidic properties of Cu/mordenite were well preserved after poisoning with potassium unlike that of vanadium catalysts. Fe-mordenite catalysts also reveale...... to be essential requirements for the high alkali resistance. Mordenite-type zeolite based catalysts could therefore be attractive alternatives to conventional SCR catalysts for biomass fired power plant flue gas treatment....

  20. NOVEL RU-NI-S ELECTRODE CATALYST FOR PEMFC

    Science.gov (United States)

    The expected results from this project include: a new formula and preparation procedures for Ru-Ni-S catalyst; demonstration of CO and S tolerance of the new catalyst; a small size PEMFC with Ru-Ni-S catalyst and good performance; an...