1,519,837 research outputs found
W. Fischer
No full text"[SX29234]. Sig. W Fischer. Dec 1941 to Sept. 1942 Winnellee."[SX29234]. Signalman W. Fischer. December 1941 to September 1942 Winnellie
Vanadia Promoted Co-AI20 3 Fischer-Tropsch Catalysts
No full textBibliography: leaves 117-124.The primary aim of this work was to study systematically V20 5 promotion on yAI203 supported cobalt-based Fischer-Tropsch catalysts. The y-Ah03 support was modified by addition of varying amounts of vanadia and was subsequently loaded with the same Co content (10 wt-%). The modified supports and catalysts were characterised using conventional characterisation methods. The physio-chemical properties of the vanadia promoted supports and catalysts were characterised using Atomic Adsorption Spectroscopy (AAS), zeta-potential measurements, and BET measurements, X-ray Diffraction (XRD), Temperature Programmed Reduction (TPR), Transmission Electron Microscopy (TEM), and CO chemisorption. Catalyst performance in the Fischer-Tropsch synthesis was tested in fixed bed reactor. A catalysts synthesised from plain y-A1203 was used as a base catalyst. Characterization results show that modification of y-Ab03 support to obtain V205 loadings beyond 1-monolayer vanadia coverage was difficult when using ion exchange. Ion-exchange equilibrium limitations might have caused the poor vanadia loadings beyond 1-monolayer coverage. The supports net surface charge as measured using zeta potential, was decreased by vanadia content in the supports. CO chemisorption results were complex and could only be modelled using dual site Langmuir model assuming the presence of two different sites absorbing CO on the Co-V-AI catalyst system. This made extraction of physical properties from this method rather difficult. Fischer Tropsch synthesis reaction was carried out at typical industrial conditions (T=220°C, P=20 bar (a), H2/CO=2 Xco-60 mol-%) for cobalt catalysts. Vanadia promoted catalysts showed a marked decrease in initial activity. However, the overall deactivation rate was lower with increasing vanadia content. The vanadia content did not affect the chain growth kinetic behavior of the catalyst in the Fischer-Tropsch synthesis hence C5+ selectivity in the Fischer-Tropsch synthesis was unperturbed by vanadia content. Increasing the vanadia content in the catalyst resulted in high n-olefin content and high 1-olefin content. The observed increase in olefin content might be due to the low catalytic activity observed for the catalysts with high vanadia loadings. The most pronounced effect of vanadia promotion on Fischer Tropsch synthesis was in the oxygenate content in the Fischer-Tropsch product. Catalysts with high vanadia loading yielded high amounts of oxygenate products; mainly alcohols and aldehydes
[Voluntary Statement by Ronald B. Fischer #1]
No full textVoluntary statement by Ronald B. Fischer as a witness in Dealey Plaza. He states the he was on the corner of Elm Street and Houston Street while the motorcade was coming through. He noticed a man, just before he heard gunshots, in the window on the fifth floor of the Texas School Book Depository building, who seemed to be lying down. He also noted a woman entering the Texas School Book Depository building while everyone else was exiting
Modeling Fischer Tropsch synthesis in two-phase, continuous, well-mixed slurry reactors
No full textIncludes abstract.Includes bibliographical references (p. 84-87).Fischer Tropsch Synthesis (FTS) is the conversion of syngas (CO and H2) to cleaner liquid transportation fuels. The modelling of such a supercritical, highly non-ideal, multi-component system requires the detailed knowledge of the reaction mechanism, reaction kinetics, phase-equilibrium and reactor technology. The objectives of this work were to: develop a complete Fischer Tropsch model, predict the hydrocarbon product distribution, determine what effect Vapour-Liquid Equilibrium (VLE) has on the product distribution, selectivity and kinetics, and determine whether the deviations from the 'ideal' Anderson-Schulz Flory (ASF) distribution can be attributed to VLE
A. Stanley T. Fischer Letter
No full textLetter to Mr. Boyer regarding his Auden thesis from Stanley Fischer. Letter states that there is no Anglo-Saxon influence on Auden\u27s poetry up to 1926. Fischer states that the earliest influences on Auden\u27s poetry were Thomas Hardy, Edward Thomas, and his father\u27s medical books.https://digitalcommons.snc.edu/audencorrespondence/1022/thumbnail.jp
Eine bildliche Quelle von Goethes Walpurgisnacht / Hans Fischer
No full textEINE BILDLICHE QUELLE VON GOETHES WALPURGISNACHT / HANS FISCHER
Eine bildliche Quelle von Goethes Walpurgisnacht / Hans Fischer (1)
Cover (1)
Chapter (3)
Eine bildliche Quelle von Goethes Walpurgisnacht (4
Fischer (illustrateur non-identifié 18..-?) : signature “Fischer” [1883]
No full textFischer (illustrateur non-identifié 18..-1..?) : signature “Fischer”. Au 16/10/2017, première attestation de cette signature sur une partition (”J’ te gobe parole d’honneur” Blanchard / Wilfrid de Scheirder 1883 - medihal-01617061)
Interview with Gerald Fischer
No full textClarke A. Chambers interviews Gerald Fischer, president of the University of Minnesota Foundation.Fischer, Gerald B.; Chambers, Clarke A.. (1997). Interview with Gerald Fischer. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/49129
The effect of temperature on the Fischer-Tropsch selectivity and further mechanistic insights
No full textIncludes bibliographical references (p. 133-145).Concern’s that the world’s energy supply will not be able to keep pace with rising energy demands, have surfaced periodically for much of the petrochemical industry’s nearly 150 year history, but each time the industry has responded with technological advances and innovations to satisfy the global energy needs. Future advances will most likely include the enhanced recovery of conventional oil, the production of extra-heavy oil / tar sands and the utilization of alternative energy production technologies (technologies other than crude oil refining). The Fischer-Tropsch Synthesis (FTS) discovered in 1923 by Fischer and Tropsch, is one of these alternative fuel production technologies and can briefly be defined as the means used to convert synthesis gas containing hydrogen and carbon monoxide over a group VIII metal catalyst to hydrocarbon products and water. Given the vast product spectrum possible for the FTS (paraffins, olefins, alcohols, carbonyls, acids and aromatics), a great deal of controversy still exists as to the chemical identity of the monomeric building block and the propagation of the hydrocarbon chain on the catalyst surface [van Dijk., 2001]. Several mechanisms have been published with the four most popular (alkyl, alkenyl, enol and CO-insertion), recently reviewed by Claeys and van Steen (2004). It must however, be appreciated that given the complexity of the FT reaction it is generally accepted that more than one mechanism may operate on the catalyst surface at any one time. Furthermore, process parameters such as temperature, total pressure, partial pressure, hydrogen to carbon monoxide ratio, space velocity and residence time all have an influence on the FT product selectivity. Because of this it becomes exceptionally complicated to determine the effects of just one parameter while taking the effects of the additional parameters into account
Opius (Cryptonastes) gracilis Fischer
No full textOpius (Cryptonastes) gracilis Fischer Opius gracilis Fischer, 1957 c: 332 –358. Opius (Cryptonastes) gracilis Fischer, 1972: 1 –620. Synonyms. Opius csikii Fischer, 1957 b; Opius minor Fischer, 1957 b; Opius nigrithorax Fischer, 1958. Distribution in Turkey. Sakarya, Bursa, Düzce, Edirne, Karabuk, Kastamonu(Fischer & Beyarslan, 2005 a), Bartin, Canakkale, Elazig, Malatya, Nevsehir (Fischer & Beyarslan, 2011); Aksaray, Erzincan, Tunceli (Fischer & Beyarslan, 2012). Distribution. Palaearctic. Austria, Bosnia Hercegovina, Bulgaria, Croatia, Czechoslovakia, Denmark, Finland, France, Germany, Hungary, Italy, Kazakhstan, Korea, Lithuania, Mongolia, Poland, Romania, Russia, Slovakia, Spain, Sweden, Switzerland, Tunisia, Turkey, United Kingdom, Uzbekistan, Yugoslavia. Hosts. Diptera. Agromyzidae: Agromyza bicophaga Hering, 1925 [Vicia tetrasperma]; A. pulla Meigen, 1830 [Genista tinctoria]; A. rondensis Strobl, 1900 [Avena sterilis, Hordeum murinum]; Amauromyza gyrans (Fallen, 1823); Chromatomyia lonicerae (Robineau-Desvoidy, 1851); C. syngenesiae Hardy, 1849 [Centaurea jacea]; Liriomyza Mik, 1894 [Centaurea jacea, Scorzonera purpurea]; L. sonchi Hendel, 1931 [Picris echioides]; L. strigata Meigen, 1830) [Pisum sativum]; L. trifolii (Burgess in Comstock, 1880) [Trifolium dubium]; Napomyza xylostei Robineau-Desvoidy, 1851; Phytomyza anemones pulsatilla Hering, 1925 [Medicago sativa]; P. dauci Hering, 1927 [Daucus]; P. ferulae Hering, 1927 [Scaligeria cretica]; P. obscura Hendel, 1920 [Clinopodium vulgare]; P. origani Hering, 1931; P. silai Hering, 1935 [Silaum silaus]; P. spondylii Robineau-Desvoidy, 1851.Published as part of Beyarslan, Ahmet & Fischer, Maximilian, 2013, Checklist of Turkish Opiinae (Hymenoptera, Braconidae), pp. 401-454 in Zootaxa 3721 (5) on page 418, DOI: 10.11646/zootaxa.3721.5.1, http://zenodo.org/record/22201
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