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A new 2-parameter desaturation function is introduced which offers a broader range of applicability to reservoir rock. Based on this function two-phase relative permeabilities are derived for oil phase and microemulsion flow. These functions are used to match a laboratory experiment by using surfactant flooding for a single surfactant system. Les auteurs présentent une nouvelle fonction de désaturation à deux paramètres qui offre une plus large gamme de possibilités d'application aux roches réservoir. On tire de cette fonction des perméabilités relatives biphasiques pour l'écoulement de la phase pétrole et d'une microémulsion. Ces fonctions sont utilisées pour reproduire une expérience de laboratoire avec injection de surfactant pour un seul système surfactant.

Abstract: Accurate prediction of temperature in CO2 injection wells is very important in order to select wellhead parameters that will yield desired bottomhole pressure and temperature and avoid complications that may occur due to phase transition along the well. This work presents analytical models related to temperature effects caused by compression of gas in the well and the transfer of heat between the gas and the surrounding rock and vice-versa. These models are integrated in an appropriate pressure model. The resulting model is combined with a robust procedure for estimating thermodynamic and transport properties of the fluid to provide accurate prediction of the temperature in the well. In addition it also offers valuable estimates of thermal conductivities in the rock layers. [Copyright &y& Elsevier]

Microalbuminuria, assessed by measuring immunoreactive albumin, is common in patients with cerebrovascular disease and is associated with increased risk of stroke. Total urinary albumin (t-uAlb) comprises both immunoreactive albumin (ir-uAlb) and nonimmunoreactive albumin (nir-uAlb). We hypothesized that t-uAlb is a more sensitive indicator of microalbuminuria than ir-uAlb, and that measurement of t-uAlb will increase the prevalence of microalbuminuria in ischemic stroke patients compared with measurement of ir-uAlb and will show a stronger correlation with the severity of stroke and oxidative stress. In urine samples from 98 patients with ischemic stroke, the albumin-to-creatinine ratios t-uAlb/uCreat and ir-uAlb/uCreat were measured by high-performance liquid chromatography (HPLC) and immunoturbidimetry (IT), and the nir-uAlb/uCreat ratio was calculated. Urinary ortho-tyrosine (o-Tyr/uCreat), an indicator of oxidative stress, was measured by HPLC. The severity of stroke was scored based on the National Institutes of Health Stroke Scale (NIHSS). The prevalence of microalbuminuria detected by HPLC was significantly higher than that detetcted by IT (66.3 vs 36.7%). Although all forms of albumin showed significant correlation with stroke severity (t-uAlb: r = 0.24, P < .05 ir-uAlb: r = 0.25, P < .05 nir-uAlb: r = 0.29, P < .05), only nir-uAlb was found to be an independent predictor of stroke severity (B = 0.20, [beta] = 0.35, P < .05). In addition, t-uAlb/uCreat and nir-uAlb/uCreat had a significant correlation with o-Tyr/uCreat (r = 0.336, P < .05 and r = 0.358, P < .05 respectively), whereas ir-uAlb/uCreat did not (r = 0.22, P > .05). Our data suggest that in acute ischemic stroke patients, t-uAlb is a more sensitive indicator of microalbuminuria than the presently used ir-uAlb. Future studies should aim to elucidate the underlying mechanisms for the relationship among urinary albumins and cerebrovascular diseases and the role of urinary albumins in risk stratification for stroke. [ABSTRACT FROM AUTHOR]