An experimental study has been conducted to compare the effect of steam injection and caustic steam injection in improving the recovery of San Ardo and Duri heavy oils. A 67 cm long x 7.4 cm O.D (outer diameter), steel injection cell is used in the study. Six thermocouples are placed at specific distances in the injection cell to record temperature profiles and thus the steam front velocity. The injection cell is filled with a mixture of oil, water and sand. Steam is injected at superheated conditions of 238oC with the cell outlet pressure set at 200 psig, the cell pressure similar to that found in San Ardo field. The pressure in the separators is kept at 50 psig. The separator liquid is sampled at regular intervals. The liquid is centrifuged to determine the oil and water volumes, and oil viscosity, density and recovery. Acid number measurements are made by the titration method using a pH meter and measuring the EMF values. The interfacial tensions of the oil for different concentrations of NaOH are also measured using a tensionometer. Experimental results show that for Duri oil, the addition of caustic results in an increase in recovery of oil from 52% (steam injection) to 59 % (caustic steam injection). However, caustic has little effect on San Ardo oil where oil recovery is 75% (steam injection) and 76 % (caustic steam injection). Oil production acceleration is seen with steam-caustic injection. With steam caustic injection there is also a decrease in the produced oil viscosity and density for both oils. Sodium hydroxide concentration of 1 wt % is observed to give the lowest oil-caustic interfacial tension. The acid numbers for San Ardo and Duri oil are measured as 6.2 and 3.57 respectively.

No description available.

No description available.

The development of waste management legislation in the 1990's has placed great importance on the sustainability of waste disposal/treatment options. Landfill of wastes is increasingly seen as a last resort and reduction, re-use and recovery of wastes is encouraged. The wastes investigated in this study (caustic tar and sewage sludges) are often disposed of by non-sustainable methods. In addition production of sewage sludge will have doubled by 2005 and disposal options are increasingly limited. Alternative treatment options are required for both these waste types that offer re-use potential. In this study the carbonisation and activation of these wastes has been demonstrated to be an effective means of treatment that also produces adsorbents that can be safely and usefully applied to treatment of aqueous waste streams. Previous studies have examined the production of clay-carbon adsorbents from spent bleaching earth and limited studies have been conducted on producing adsorbents from sewage sludges. However, the majority of these have limited investigations to production of oils from sludge and no previous studies of caustic tar carbonisation have been conducted. Treatment of caustic tar involved neutralisation with HCl and absorption of the organic content of the waste by Fullers or Acid Activated Earth. The clay-waste mix was subsequently carbonised (375°C for 2 hours) and activated using an optimised ZnClj activation procedure (600°C for 1 hour). Activated carbons were produced from sewage sludges using carbonisation (500°C for 2 hours), CO^ activation (700°C for I hour) and ZnCl^ activation (450°C for 2 hours and 600°C for 1 hour). The adsorbents produced had well developed porosity and large surface areas (up to 225mVg for caustic tar derived carbons and up to 995mVg for sewage sludge based carbons) and were adsorptive of a range of organic pollutants common in effluents. ZnC^ activated, un-digested sewage sludges proved to be the most effective adsorbents. COj activated sewage sludges and caustic tar derived carbons had similar adsorption capacities for the organic pollutants studied. Leaching tests demonstrated that metals present in the adsorbents other than the ZnClj activated carbons were not readily leachable and would not prevent re-use of the carbons in the treatment of aqueous effluents.

Orientador: Erika V. Paiva Ortolan / Banca: Walmar Kerche de Oliveira / Banca: João Gilberto Maksound Filho / Resumo: A ingestão acidental de substâncias cáusticas constitui um grave problema de saúde pública, ocorrendo principalmente na faixa etária pediátrica, sendo a estenose do esôfago uma complicação frequente. A dilatação esofágica é o tratamento de escolha para estes casos. Várias substâncias já foram testadas nos casos refratários à dilatação, porém com resultados insatisfatórios. A mitomicina C, agente quimioterápico capaz de inibir a síntese protéica e a proliferação de fibroblastos, tem sido usada com sucesso em estenoses esofágicas refratárias às dilatações. No entanto, há poucos estudos experimentais descrevendo como a mitomicina C interage com o tecido lesado e qual o melhor momento para o seu uso após a lesão cáustica. Avaliar os efeitos do uso tópico da mitomicina C, associada ou não à dilatação esofágica, aplicada em diferentes momentos após a lesão cáustica do esôfago de ratos com soda cáustica (NAOH 10%). Para efeito de comparação, utilizou-se ratos nos quais se infundiu solução salina (SF0,9%) no esôfago. Quarenta e oito ratos foram divididos em 6 grupos com 8 ratos cada: grupo manipulado ou sham (Gs), grupo controle (Gc), grupo com lesão cáustica e não tratado (Gnt), grupo com lesão cáustica e aplicação de mitomicina C (MMC) logo após a lesão (GmmcD0), grupo com lesão cáustica e aplicação de MMC 14 dias após a lesão (GmmcD14) e grupo com lesão cáustica seguido de dilatação e aplicação de MMC 14 dias após a lesão (Gdil+mmcD14). A lesão cáustica foi produzida seguindo o modelo descrito por Gehanno & Guedon modificado pelo nosso grupo de pesquisa, com NaOH10%. Em 4 momentos de avaliação (7º, 14º, 21º, e 28º dias de pós operatório - PO), todos os animais foram pesados. No 7º e 21º dias de PO, 4 ratos de cada grupo foram submetidos ao exame contrastado de esôfago. No 28º dia de PO... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The accidental ingestion of caustic substances is an important problem of public health, occurring mainly in childhood. The esophageal stricture is a frequent complication and esophageal dilation is the treatment of choice. Many agents have been tested when esophageal dilation is unsatisfactory, although with poor results. Mitomycin C, a chemotherapeutic agent that inhibits protein synthesis and the proliferation of fibroblasts, has been used successfully in cases of esophageal stricture that are refractory to dilation. However, there are few experimental studies describing how this substance interacts with damaged tissue and the best time window for its use after caustic injury. The purpose of this study was to evaluate the effects of the topical application of MMC in rats, with or without associated esophageal dilatation, at different moments after the induction of a caustic esophageal lesion by NaOH10%. 48 Wistar rats were divided into 6 groups of 8 animals each: sham group (SG), control group (CG), injured group but not treated (NTG), injured group with mitomycin C application immediately after the caustic lesion (MMCD0G), injured group with MMC application 14 days after induction of caustic lesion (MMCD14G) and injured group with esophageal dilation and application 14 days after caustic lesion (MMCD14+DILG). The caustic injury was produced as described by Gehanno & Guedon, modified by our group, with NaOH10%. There were 4 moments of evaluation: 7°, 14°, 21° and 28° days after caustic injury, when rats were weighted. At 7° and 21° days after injury, it was performed the esophagograms of 4 rats of each group. On day 28 after caustic injury, all animals were sacrificed, and morphological and histopathological analyses were performed on the esophageal specimens, besides... (Complete abstract click electronic access below) / Mestre

No description available.

This study discusses the three-dimensional refraction of progressive wave trains propagating over a bottom of circular concentric contours and the results are expressed in a polar coordinate. First, a general differential formulation of refraction is derived via three different methods: by transferring from its original Cartesian form to the polar coordinate, by applying the Fermat¡¦s principle in polar coordinate, and by applying the conservation of waves in polar coordinate. All three approaches give the same governing equation; hence, its correctness is verified. Based on this governing equation, the wave ray, the phase function, the constant phase line, and the refraction coefficient are all determined. In the present refraction problem for an originally uniform wave train propagating over a bottom of circular concentric contours, a few special features, including the cusps of constant phase lines due to the effect of bottom, and the envelope composed of these cusps, are present. All these refraction properties can be expressed in terms of both a snapshot and a time evolution of constant phase lines. In the lee side of the shoal, there exists a sheltered zone that is enclosed by the envelope of the cusps. In this zone, wave rays intersect and the corresponding caustic problem arises, and all possible combinations of intersecting rays are also specifically described in this study. The difficulty of classical ray theory for the caustic problem is overcome and the caustic phenomenon and its refraction coefficients are determined explicitly in this study.

The thesis investigates the solubility of various sodium salts present in the waste tanks at the Hanford nuclear site. The experiments were conducted in different concentrations of caustic and in water at 25°C and 50°C. The results obtained from these studies will be used to improve existing databases for the Environmental Simulation Program (ESP, available from OLI Systems, Inc.), thereby increasing its accuracy in predicting waste behavior under high ionic strength conditions. Experiments were performed on the following systems: 1) NaF - NaNO3 - NaOH, 2) Na3PO4 - NaNO3 - NaOH, 3) NaF - Na3PO4 - 1m NaNO3 - NaOH, and 4) NaF - Na3PO4 - 3m NaNO3 - NaOH. The results obtained from these experiments were then compared to the ESP predictions and the available literature data. Comparision of the experimental work with the available literature data revealed that the data obtained from this study is in agreement with previous studies for the NaF - NaOH, NaNO3 - NaOH, and Na3PO4 - NaOH systems. This is the first report on solubilities for the Na - F - PO4 - OH system with added nitrate. The presence of sodium hydroxide was found to lower the solubility of natrophosphate, Na7F(PO4)2.19H2O. The solubility of this double salt was also significantly lowered in the presence of sodium nitrate. Error analysis of the experimental data was performed and indicated that the experimental molalities were accurate to within an average of + 0.02.

Made available in DSpace on 2014-06-11T19:22:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-18Bitstream added on 2014-06-13T19:27:12Z : No. of bitstreams: 1 bustamante_tf_me_botfm.pdf: 3625249 bytes, checksum: 92a758c187e8eec63582c316baef9e88 (MD5) / Universidade Estadual Paulista (UNESP) / A ingestão acidental de substâncias cáusticas constitui um grave problema de saúde pública, ocorrendo principalmente na faixa etária pediátrica, sendo a estenose do esôfago uma complicação frequente. A dilatação esofágica é o tratamento de escolha para estes casos. Várias substâncias já foram testadas nos casos refratários à dilatação, porém com resultados insatisfatórios. A mitomicina C, agente quimioterápico capaz de inibir a síntese protéica e a proliferação de fibroblastos, tem sido usada com sucesso em estenoses esofágicas refratárias às dilatações. No entanto, há poucos estudos experimentais descrevendo como a mitomicina C interage com o tecido lesado e qual o melhor momento para o seu uso após a lesão cáustica. Avaliar os efeitos do uso tópico da mitomicina C, associada ou não à dilatação esofágica, aplicada em diferentes momentos após a lesão cáustica do esôfago de ratos com soda cáustica (NAOH 10%). Para efeito de comparação, utilizou-se ratos nos quais se infundiu solução salina (SF0,9%) no esôfago. Quarenta e oito ratos foram divididos em 6 grupos com 8 ratos cada: grupo manipulado ou sham (Gs), grupo controle (Gc), grupo com lesão cáustica e não tratado (Gnt), grupo com lesão cáustica e aplicação de mitomicina C (MMC) logo após a lesão (GmmcD0), grupo com lesão cáustica e aplicação de MMC 14 dias após a lesão (GmmcD14) e grupo com lesão cáustica seguido de dilatação e aplicação de MMC 14 dias após a lesão (Gdil+mmcD14). A lesão cáustica foi produzida seguindo o modelo descrito por Gehanno & Guedon modificado pelo nosso grupo de pesquisa, com NaOH10%. Em 4 momentos de avaliação (7º, 14º, 21º, e 28º dias de pós operatório - PO), todos os animais foram pesados. No 7º e 21º dias de PO, 4 ratos de cada grupo foram submetidos ao exame contrastado de esôfago. No 28º dia de PO... / The accidental ingestion of caustic substances is an important problem of public health, occurring mainly in childhood. The esophageal stricture is a frequent complication and esophageal dilation is the treatment of choice. Many agents have been tested when esophageal dilation is unsatisfactory, although with poor results. Mitomycin C, a chemotherapeutic agent that inhibits protein synthesis and the proliferation of fibroblasts, has been used successfully in cases of esophageal stricture that are refractory to dilation. However, there are few experimental studies describing how this substance interacts with damaged tissue and the best time window for its use after caustic injury. The purpose of this study was to evaluate the effects of the topical application of MMC in rats, with or without associated esophageal dilatation, at different moments after the induction of a caustic esophageal lesion by NaOH10%. 48 Wistar rats were divided into 6 groups of 8 animals each: sham group (SG), control group (CG), injured group but not treated (NTG), injured group with mitomycin C application immediately after the caustic lesion (MMCD0G), injured group with MMC application 14 days after induction of caustic lesion (MMCD14G) and injured group with esophageal dilation and application 14 days after caustic lesion (MMCD14+DILG). The caustic injury was produced as described by Gehanno & Guedon, modified by our group, with NaOH10%. There were 4 moments of evaluation: 7°, 14°, 21° and 28° days after caustic injury, when rats were weighted. At 7° and 21° days after injury, it was performed the esophagograms of 4 rats of each group. On day 28 after caustic injury, all animals were sacrificed, and morphological and histopathological analyses were performed on the esophageal specimens, besides... (Complete abstract click electronic access below)

We explore the dynamics of integrable and chaotic quantum many-body systems with a focus on universal structures known as caustics, which are a type of singularity categorized by catastrophe theory. Papers I and II study light cones in quantum spin chains, which we show are caustics and therefore inherits specific functional forms. For integrable systems, the edge of the cone is a fold catastrophe, making the wavefunction locally of Airy form. We also identify the cusp catastrophe in the XY model, thus the secondary light cone is a Pearcey function. Vortex pairs appear in the dynamics, are sensitive to phase transitions, and permit the extraction of critical scaling exponents. In paper II we use a Gaussian wavefront form to distinguish integrable and chaotic models. Writing the wavefront as exp[−m(x)(x − vt)2 + b(x)t], the scaling of coefficients m(x) and b(x) is the diagnostic. The local Airy function description in free models leads to a power-law ∼ x^{−n/3} scaling, while for the chaotic case the scaling is exponential ∼ e^{−cx}. In Paper III, we study the function Fn(t) = <(A(t)B)^n>, a generalization of the four-point out-of-time ordered correlator (OTOC) F2(t), for an integrable system and show that the function Fn(t) can be recast as the return amplitude of an effective time dependent chaotic system, exhibiting signals of chaos such as a positive Lyapunov exponent, spectral statistics consistent with random matrix theory, and relaxation. In Paper IV we perform a comprehensive investigation of caustics in many-body systems in (1+1)- and (2+1)-dimensional Fock space and time. We show how a hierarchy of caustics appear in the dynamics of many-body models, using two- and three-mode Bose-Hubbard models as guiding systems. We show that, in the case of the trimer, high dimensional caustics appear and are organized by the catastrophe X9. / Thesis / Doctor of Philosophy (PhD)