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Towards Understanding Interfacial Phenomena in Polymer-CO<sub>2</sub> SystemsTalreja, Manish 01 September 2010 (has links)
No description available.
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CO<sub>2</sub> Reduction on Cu Oxide PhotoelectrodesVasconi, Melissa A. 12 July 2012 (has links)
No description available.
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FILM FORMATION AND CO2 CORROSION IN THE PRESENCE OF ACETIC ACIDNafday, Omkar A. January 2004 (has links)
No description available.
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CO <sub>2</sub>corrosion mechanistic modeling in horizontal slug flowWang, Hongwei January 2002 (has links)
No description available.
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Removal Mechanisms of Protective Iron Carbonate Layer in Flowing SolutionsYang, Yang 11 September 2012 (has links)
No description available.
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The effect of interfacial tension in CO<sub>2</sub> assisted polymer processingHongbo, Li 29 September 2004 (has links)
No description available.
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Dense Carbon Dioxide Assisted Polymer Processing at the NanoscaleEllis, Jeffrey LeClair 08 September 2009 (has links)
No description available.
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Extratos de sementes de gergelim preto (Sesamum indicum L) obtidos via CO<sub>2</sub> supercrítico: isotermas de rendimento global, dados cinéticos e ajustes, ácidos graxos totais, fitosteróis e efeitos neuroprotetoresBOTELHO, José Rafael Santos 17 December 2013 (has links)
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Previous issue date: 2013 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / Na medicina popular brasileira, sementes de gergelim preto (Sesamum indicum L) é
um dos mais importantes ingrediente presentes em um chá usado para tratar vítimas de
acidente vascular encefálico (AVE). Porém, o isolamento de extratos de gergelim preto
para fins medicinais usando a tecnologia do fluido supercrítico não foi realizado. O objetivo
deste trabalho foi investigar algumas variáveis de processo da extração com fluido
supercrítico em sementes de gergelim preto para gerar extratos aplicáveis a pesquisa
do AVE isquêmico focal. Duas isotermas (40 e 60 ºC) foram exploradas, combinadas
com pressões de 200-400 bar, em vazão mássica de CO<sub>2</sub> constante de 5,9 x 10<sup>-5</sup> kg/s. Os
rendimentos globais foram de 37-53% em base seca. O maior rendimento foi obtido em
60 ºC e 400 bar. A composição de ácidos graxos mostrou uma elevada razão de insaturados/
saturados. A análise de conteúdo de fitosteróis no extrato de maior rendimento
revelou maiores quantidades de β-sitosterol + sitostanol, colesterol, campesterol + campestanol
+ 24-metileno colesterol, Δ-5 avenasterol and estigmasterol, enquanto que menores
níveis de Δ-5,24 estigmastadienol, brassicasterol, clerosterol + Δ-5-23 estigmastadienol,
Δ-7 avenasterol, eritrodiol and Δ-7 estigmastenol foram observados. As curvas
de extração das extrações com fluido supercrítico no menor e maior rendimento mássico
(200 e 400 bar a 60 ºC) foram ajustadas pelos modelos de Tan e Liou (1989), Martinez
et al. (2003), Esquível et al. (1999), Goto et al. (1993) e Sovová (1994 e 2012). Os modelos
de Tan e Liou (1989), Goto et al. (1993) e Sovová (1994 e 2012) apresentaram as
melhores valores nominais de somas residuais dos quadrados. Experimentos pilotos
sugerem que o extrato obtido via fluido supercrítico de gergelim preto é neuroprotetor
em relação a isquemia focal por endotelina-1 no córtex motor de ratos machos adultos,
observada a redução da área de infarto isquêmico. / In Brazilian folk medicine, black sesame (Sesamum indicum L) seeds is one of the
most important ingredients present in the tea used to treat encephalic stroke victims.
Nevertheless, isolation of black sesame extracts to medicinal finality using supercritical
fluid technology has not been performed. The objective of this work was to investigate
some process variables of supercritical fluid extraction in black sesame to generate extracts
applicable in stroke research. Two isothermal (40 and 60 °C) were explored,
combined with pressures that ranged from 200-400 bar, at a constant CO<sub>2</sub> mass flow
rate of 5,9 x 10<sup>-5</sup> kg/s. The global yields ranged from 37-53% in dry basis. The highest
mass yield was obtained at 60 °C and 400 bar. The fatty acid composition comprised a
high unsaturated/saturated ratio. Chromatographic analysis of phytosterol content in the
high global yield extract revealed higher amounts of β-sitosterol + sitostanol, cholesterol,
campesterol + campestanol + 24-methylene cholesterol, Δ-5 avenasterol and
stigmasterol, while lower levels of Δ-5,24 stigmastadienol, brassicasterol, clerosterol +
Δ-5-23 stigmastadienol, Δ-7 avenasterol, eritrodiol and Δ-7 stigmastenol were present in
the black sesame extract. Overall extraction curves from the supercritical fluid extraction
in lower and higher global yields (200 e 400 bar at 60 °C) fitted the Tan and Liou
(1989), Martinez et al. (2003), Esquível et al. (1999), Goto et al. (1993) e Sovová models
(1994 and 2012). The models of Tan and Liou (1989), Goto et al. (1993) and Sovová
(1994 and 2012) presented the best residual sum of squares values. Pilot experiments
suggest that black sesame extract is neuroprotective following endothelin-1 induced
focal ischemia into the motor cortex of male adult rat, observing indications that a prejudicial
cell form for the stroke`s status was inhibited by the treatment.
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Synthesis of Amine-Modified Aerogel Sorbents and Metal-Organic Framework-5 (MOF-5) Membranes for Carbon Dioxide SeparationJanuary 2010 (has links)
abstract: Amine-modified solid sorbents and membrane separation are promising technologies for separation and capture of carbon dioxide (CO2) from combustion flue gas. Amine absorption processes are mature, but still have room for improvement. This work focused on the synthesis of amine-modified aerogels and metal-organic framework-5 (MOF-5) membranes for CO2 separation. A series of solid sorbents were synthesized by functionalizing amines on the surface of silica aerogels. This was done by three coating methods: physical adsorption, magnetically assisted impact coating (MAIC) and atomic layer deposition (ALD). CO2 adsorption capacity of the sorbents was measured at room temperature in a Cahn microbalance. The sorbents synthesized by physical adsorption show the largest CO2 adsorption capacity (1.43-1.63 mmol CO2/g). An additional sorbent synthesized by ALD on hydrophilic aerogels at atmospheric pressures shows an adsorption capacity of 1.23 mmol CO2/g. Studies on one amine-modified sorbent show that the powder is of agglomerate bubbling fluidization (ABF) type. The powder is difficult to fluidize and has limited bed expansion. The ultimate goal is to configure the amine-modified sorbents in a micro-jet assisted gas fluidized bed to conduct adsorption studies. MOF-5 membranes were synthesized on α-alumina supports by two methods: in situ synthesis and secondary growth synthesis. Characterization by scanning electron microscope (SEM) imaging and X-ray diffraction (XRD) show that the membranes prepared by both methods have a thickness of 14-16 μm, and a MOF-5 crystal size of 15-25 μm with no apparent orientation. Single gas permeation results indicate that the gas transport through both membranes is determined by a combination of Knudsen diffusion and viscous flow. The contribution of viscous flow indicates that the membranes have defects. / Dissertation/Thesis / M.S. Chemical Engineering 2010
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H<sub>2</sub>S Multiphase Flow Loop: CO<sub>2</sub> Corrosion in the Presence of Trace Amounts of Hydrogen SulfideBrown, Bruce N. January 2004 (has links)
No description available.
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