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Journal articles on the topic 'Winsor II'

Author: Grafiati

Published: 4 June 2021

Last updated: 12 February 2022

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1

Behjatmanesh-Ardakani, Reza, and Mehdi Nikfetrat. "Study of Winsor I to Winsor II Transitions in a Lattice Model." Journal of Physical Chemistry B 111, no. 25 (June 2007): 7169–75. http://dx.doi.org/10.1021/jp070752g.

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2

Biais, J., M. Barthe, M. Bourrel, B. Clin, and P. Lalanne. "Salt partitioning in Winsor Type II systems." Journal of Colloid and Interface Science 109, no. 2 (February 1986): 576–85. http://dx.doi.org/10.1016/0021-9797(86)90339-5.

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3

Steytler, David C., Thomas F. Towey, Brian H. Robinson, and N. Zeynep Atay. "Mechanisms of Solute Interfacial Transfer in Winsor-II Systems." Langmuir 17, no. 2 (January 2001): 417–26. http://dx.doi.org/10.1021/la0009902.

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4

Chaiko, D. J. "Partitioning of Polymeric Plutonium(IV) in Winsor II Microemulsion Systems." Separation Science and Technology 27, no. 11 (September 1992): 1389–405. http://dx.doi.org/10.1080/01496399208019432.

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5

Eriksson, Jan Christer, Stig Ljunggren, Willem K. Kegel, and Henk N. W. Lekkerkerker. "Entropy and droplet size distributions of Winsor I and II microemulsions." Colloids and Surfaces A: Physicochemical and Engineering Aspects 183-185 (July 2001): 347–60. http://dx.doi.org/10.1016/s0927-7757(01)00526-x.

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6

Plucinski, P., and W. Nitsch. "Kinetics of the interfacial ion exchange in winsor II microemulsion systems." Journal of Colloid and Interface Science 154, no. 1 (November 1992): 104–12. http://dx.doi.org/10.1016/0021-9797(92)90082-w.

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7

Brejza, Edwina V., and E. Susana Perez de Ortiz. "Phenomena Affecting the Equilibrium of Al(III) and Zn(II) Extraction with Winsor II Microemulsions." Journal of Colloid and Interface Science 227, no. 1 (July 2000): 244–46. http://dx.doi.org/10.1006/jcis.2000.6854.

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8

Eastoe, Julian, Stewart Chatfield, and Richard Heenan. "Effect of Counterion Radius on Surfactant Properties in Winsor II Microemulsion Systems." Langmuir 10, no. 6 (June 1994): 1650–53. http://dx.doi.org/10.1021/la00018a005.

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9

Shan, Zeng, Yang Yan-zhao, Zhu Tao, Han Jian, and Luo Chang-Hong. "Uranium(VI) extraction by Winsor II microemulsion systems using trialkyl phosphine oxide." Journal of Radioanalytical and Nuclear Chemistry 265, no. 3 (August 2005): 419–21. http://dx.doi.org/10.1007/s10967-005-0843-1.

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10

Tao, Zhu, Yang Yan-Zhao, Liu Zhan-Yu, and Xia Chuan-Bo. "Extraction of cobalt by CTMAB - pentanol - heptane - HCl Winsor II microemulsion systems." Journal of Radioanalytical and Nuclear Chemistry 267, no. 2 (January 2006): 401–6. http://dx.doi.org/10.1007/s10967-006-0062-4.

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11

Xia, Hansong, Jiang Yu, Yangyang Jiang, Iram Mahmood, and Huizhou Liu. "Physicochemical Features of Ionic Liquid Solutions in the Phase Separation of Penicillin(II): Winsor II Reversed Micelle." Industrial & Engineering Chemistry Research 46, no. 7 (March 2007): 2112–16. http://dx.doi.org/10.1021/ie060606h.

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12

Baran,, Jimmie R., Gary A. Pope, William H. Wade, and Vinitha Weerasooriya. "Water/Chlorocarbon Winsor I ⇔ III ⇔ II Microemulsion Phase Behavior with Alkyl Glucamide Surfactants." Environmental Science & Technology 30, no. 7 (January 1996): 2143–47. http://dx.doi.org/10.1021/es950514b.

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13

Manna, Abhijit, Toyoko Imae, Toshinobu Yogo, Keigo Aoi, and Midori Okazaki. "Synthesis of Gold Nanoparticles in a Winsor II Type Microemulsion and Their Characterization." Journal of Colloid and Interface Science 256, no. 2 (December 2002): 297–303. http://dx.doi.org/10.1006/jcis.2002.8691.

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14

Ghosh, S., and R. T. Johns. "An Equation-of-State Model To Predict Surfactant/Oil/Brine-Phase Behavior." SPE Journal 21, no. 04 (August 15, 2016): 1106–25. http://dx.doi.org/10.2118/170927-pa.

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Summary Surfactant/polymer (SP) floods have significant potential to recover waterflood residual oil in shallow oil reservoirs. A thorough understanding of surfactant/oil/brine-phase behavior is critical to design SP-flood processes. Current practices involve repetitive laboratory experiments of dead crude at atmospheric pressure in a salinity scan that aims at finding an “optimum formulation” of chemicals for targeted oil reservoirs. Although considerable progress has been made in developing surfactants and polymers that increase the potential of a chemical enhanced-oil-recovery (EOR) project, very little progress has been made to predict phase behavior as a function of formulation variables such as pressure, temperature, and oil equivalent alkane carbon number (EACN). The empirical Hand (1930) plot is still used today to model the microemulsion-phase behavior with little predictive capability because these and other formulation variables change. Such models could lead to incorrect recovery predictions and improper SP-flood designs. In this research, we develop a new predictive-phase-behavior model and introduce a new factor β to account for pressure changes in the HLD equation. This new HLD equation is coupled with the net-average-curvature (NAC) model to predict phase volumes, solubilization ratios, and microemulsion-phase transitions (Winsor II–, Winsor III, and Winsor II+). The predictions of key parameters are compared with experimental data and are within relative errors of 4% (average 2.35%) for measured optimum salinities and 17% (average 10.55%) for optimum solubilization ratios. This paper is the first to use the HLD/NAC model to predict microemulsion-phase behavior for live crudes, including optimal solubilization ratio and the salinity width of the three-phase Winsor III region at different temperatures and pressures. Although the effect of pressure variations on microemulsion-phase behavior is generally thought to be small compared with temperature-induced changes, we show here that this is not necessarily the case. The predictive approach relies on tuning the model to limited experimental data (such as at atmospheric pressure) similar to what is performed for equation-of-state (EOS) modeling of miscible gasfloods. This new EOS-like model could significantly aid the design of chemical floods where key variables change dynamically, and in screening of potential candidate reservoirs for chemical EOR.

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15

Manna, Abhijit, B. D. Kulkarni, Krisanu Bandyopadhyay, and K. Vijayamohanan. "Synthesis and Characterization of Hydrophobic, Approtically-Dispersible, Silver Nanoparticles in Winsor II Type Microemulsions." Chemistry of Materials 9, no. 12 (December 1997): 3032–36. http://dx.doi.org/10.1021/cm9703740.

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16

Baran, Jimmie R. "Winsor I⇔;III⇔II Microemulsion Phase Behavior of Hydrofluoroethers and Fluorocarbon/Hydrocarbon Catanionic Surfactants." Journal of Colloid and Interface Science 234, no. 1 (February 2001): 117–21. http://dx.doi.org/10.1006/jcis.2000.7284.

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17

Vijayalakshmi, Chandra S., Ananth V. Annapragada, and Erdogan Gulari. "Equilibrium Extraction and Concentration of Multivalent Metal Ion Solutions by Using Winsor II Microemulsions." Separation Science and Technology 25, no. 6 (May 1990): 711–27. http://dx.doi.org/10.1080/01496399008050361.

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18

Vijayalakshmi, Chandra S., and Erdogan Gulari. "An Improved Model for the Extraction of Multivalent Metals in Winsor II Microemulsion Systems." Separation Science and Technology 26, no. 2 (February 1991): 291–99. http://dx.doi.org/10.1080/01496399108050473.

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19

Kegel, Willem K., Igor Bodnar, and Henk N. W. Lekkerkerker. "Bending Elastic Moduli of the Surfactant Film and Properties of a Winsor II Microemulsion System." Journal of Physical Chemistry 99, no. 10 (March 1995): 3272–81. http://dx.doi.org/10.1021/j100010a043.

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20

Shioi, Akihisa, and Makoto Harada. "Model for Geometry of Surfactant Assemblies in the Oil-Rich Phase of Winsor II Microemulsions." JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 29, no. 1 (1996): 95–104. http://dx.doi.org/10.1252/jcej.29.95.

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21

Eastoe, Julian, Steward Chatfield, and Richard Heenan. "Additions and Corrections. Effect of Counterion Radius on Surfactant Properties in Winsor II Microemulsion Systems." Langmuir 10, no. 10 (October 1994): 3918. http://dx.doi.org/10.1021/la00022a600.

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22

Xia, Huifen, Lihui Wang, Peihui Han, Ruibo Cao, Siqi Zhang, and Xianda Sun. "Microscopic Residual Oil Distribution Characteristics and Quantitative Characterization of Producing Degree Based on Core Fluorescence Analysis Technology." Geofluids 2021 (January 5, 2021): 1–17. http://dx.doi.org/10.1155/2021/8827721.

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In this study, to address the insufficiency of research on the distribution characteristics and quantitative characterization of oil, water, and rock in a reservoir, laser confocal and core fluorescence analysis techniques are combined with core flooding experiments to investigate oil–water distribution characteristics in the core and the microscopic origin of residual oil. The results obtained show that the three-dimensional (3D) distribution characteristics of oil, water, and rock can be depicted using a laser confocal technique. Free and bound states are dominated by water flooding, and their total proportion is 93.65%, while the semibound state only accounts for 6.35% of the total. Polymer flooding has clear effects such as production of cluster-like residual oil, interparticle adsorption state residual oil, pore surface oil film, and corner residual oil. After alkali-surfactant-polymer (ASP) flooding, the residual oil produced at the lowest degree corresponds to particle adsorption oil, pore surface oil films, and interparticle adsorption state residual oil. The emulsion transition process in porous media, i.e., Winsor I→Winsor III→Winsor II, is studied. Moreover, the fluorescence analysis technology is used to clarify the causes for residual oil production, namely, pore structure, crude oil viscosity, the Jia Min effect, particle migration, and adsorption capacity. The combination of laser confocal and fluorescence analysis technology can help realize the three-dimensional reconstruction of the fluid in the core, and it can quantitatively characterize the microscopic residual oil. According to the analysis results, it can also guide the formulation and adjustment of oilfield development plans.

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23

Bartoň, Jaroslav, Yanko Sarov, and Ignác Capek. "Polymerization of vinyl monomers in separated Winsor II (w/o) and Winsor I (o/w) microemulsion phases. Part 1: preparation and characterization of polymerizable vinyl-monomer-containing microemulsions." Designed Monomers and Polymers 9, no. 2 (January 2006): 153–68. http://dx.doi.org/10.1163/156855506776382682.

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24

YANG, Y., T. ZHU, C. XIA, X. XIN, L. LIU, and Z. LIU. "Study on the extraction of cobalt and nickel from NH4SCN solution by Winsor II microemulsion system." Separation and Purification Technology 60, no. 2 (April 20, 2008): 174–79. http://dx.doi.org/10.1016/j.seppur.2007.08.006.

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25

Vijayalakshmi, Chandra S., and Erdogan Gulari. "Extraction of Trivalent Metals and Separation of Binary Mixtures of Metals Using Winsor II Microemulsion Systems." Separation Science and Technology 27, no. 2 (February 1992): 173–98. http://dx.doi.org/10.1080/01496399208018872.

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26

Roshanfekr, M., R. T. T. Johns, G. Pope, L. Britton, H. Linnemeyer, C. Britton, and A. Vyssotski. "Simulation of the Effect of Pressure and Solution Gas on Oil Recovery From Surfactant/Polymer Floods." SPE Journal 17, no. 03 (August 23, 2012): 705–16. http://dx.doi.org/10.2118/125095-pa.

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Summary Surfactant/polymer (SP) and alkali/surfactant/polymer flooding is of current interest because of the need to recover residual oil after primary and secondary recovery. If designed properly, these enhanced-oil-recovery processes can give very high oil recoveries. Microemulsion phase behavior plays a central role in process performance and is typically measured by performing salinity scans in glass pipettes at atmospheric pressure and reservoir temperature using dead crude oil from the reservoir of interest. There have been only a few experiments reported in the literature on live oil at reservoir pressure and temperature, and the importance of those experimental results is conflicting. This paper investigates the effect of pressure and solution gas on microemulsion phase behavior and its impact on oil recovery. We examine previous data reported in the literature, and report new measurements with live oil to show that the optimum parameters can change significantly. The experiments show that while pressure induces a phase transition from upper microemulsion (Winsor Type II+) to lower microemulsion (Winsor Type II—), solution gas does the opposite. An increase in pressure decreases the optimum solubilization ratio and shifts the optimum salinity to a larger value. Adding methane to dead oil at constant pressure does the reverse. Thus, these effects are coupled and both must be taken into account. Using a numerical simulator, we show that these changes in the optimum conditions can significantly impact oil recovery if not accounted for in the SP design.

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27

Van Aken, George A., J. Theo G. Overbeek, Phil L. De Bruijn, and Henk N. W. Lekkerkerker. "Partitioning of Salt in Winsor II Microemulsion Systems with an Anionic Surfactant and the Consequences for the Phase Behavior." Journal of Colloid and Interface Science 157, no. 1 (April 1993): 235–43. http://dx.doi.org/10.1006/jcis.1993.1181.

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28

Khomane, R. B., Abhijit Manna, A. B. Mandale, and B. D. Kulkarni. "Synthesis and Characterization of Dodecanethiol-Capped Cadmium Sulfide Nanoparticles in a Winsor II Microemulsion of Diethyl Ether/AOT/Water." Langmuir 18, no. 21 (October 2002): 8237–40. http://dx.doi.org/10.1021/la011567b.

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29

Tapias- Hernández, Fabián Andrés, and Rosangela Barros Zanoni Lopes Moreno. "Assessment of a surfactant- polymer formulation for conditions in a Colombian field." CT&F - Ciencia, Tecnología y Futuro 9, no. 1 (May 10, 2019): 47–63. http://dx.doi.org/10.29047/01225383.152.

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The surfactant-polymer (SP) process is one of the Chemical Enhanced Oil Recovery (CEOR) methods used in the industry. It has been continuously studied; however, it is still a challenge for the petroleum industry due to the difficulty to design the solution to be injected and forecast process performance. This paper is intended to contribute to the design of fluids used in an SP process based on some previously known properties and conditions. Hence, reservoir and fluid properties of a Colombian Field were used as reference parameters to select the polymer and surfactant. Then, the effects of salts, temperature, and surfactant on tailor-made polymer solutions were determined through a rheological study. Ostwald-de Waele and Carreau-Yasuda models adjusted the measured viscosity data against shear rate, while Arrhenius equation fitted viscosity values at 7,8 s-1 against temperature. The surfactant performance was analyzed using phase behavior tests, and the Chun Huh equations determined the interfacial tension (IFT) values. The Bancroft’s rule was used as a qualitative verification tool of the kind of micro- emulsion formed. From rheology, we concluded that the viscous modulus is predominant for all polymer solutions, and the fluid thickness is reduced due to the presence of divalent cations and raise on temperature, salts or surfactant concentration. On the other hand, the observed phase behavior corresponded to a transition Winsor II to I without finding any Winsor III micro-emulsion. Therefore, some criteria were proposed to select the optimal conditions. For the desired conditions, the reduction of IFT reached values ranging in magnitudes of 10-3 to 10-4 [mN/m]. These values are usually associated with an improved oil recovery factor.

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30

Shioi, Akihisa, Makoto Harada, and Mitsuru Tanabe. "WTL: effects of organic solvents on the aggregates' geometry and Winsor II/III transition in the sodium bis(2-ethylhexyl) phosphate system." Journal of Physical Chemistry 97, no. 31 (August 1993): 8281–88. http://dx.doi.org/10.1021/j100133a026.

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31

Khodaparast, Pooya, and Russell T. Johns. "A Continuous and Predictive Viscosity Model Coupled to a Microemulsion Equation of State." SPE Journal 25, no. 03 (August 23, 2019): 1070–81. http://dx.doi.org/10.2118/190278-pa.

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Summary Surfactant floods can attain high oil recovery if optimal conditions with ultralow interfacial tensions (IFT) are achieved in the reservoir. A recently developed equation-of-state (EoS) phase-behavior net-average-curvature (NAC) model based on the hydrophilic-lipophilic difference (HLD-NAC) has been shown to fit and predict phase-behavior data continuously throughout the Winsor I, II, III, and IV regions. The state-of-the-art for viscosity estimation, however, uses empirical nonpredictive based on of fits to salinity scans, even though other parameters change, such as the phase number and compositions. In this paper, we develop the first-of-its-kind microemulsion viscosity model that gives continuous viscosity estimates in composition space. This model is coupled to our existing HLD-NAC phase-behavior EoS. The results show that experimentally measured viscosities in all Winsor regions (two- and three-phase) are a function of phase composition, temperature, pressure, salinity, and the equivalent alkane carbon number (EACN). More specifically, microemulsion viscosities associated with the three-phase invariant point have an M shape as formulation variables change, such as from a salinity scan. The location and magnitude of viscosity peaks in the M are predicted from two percolation thresholds after tuning to viscosity data. These percolation thresholds as well as other model parameters change linearly with EACN and brine salinity. We also show that the minimum viscosity in the M shape correlates linearly with EACN or the viscosity ratio. Other key parameters in the model are also shown to linearly correlate with the EACN and brine salinity. On the basis of these correlations, two- and three-phase microemulsion viscosities are determined in five-component space (surfactant, two brine components, and two oil components) independent of flash calculations. Phase compositions from the EoS flash calculations are entered into the viscosity model. Fits to experimental data are excellent, as well as viscosity predictions for salinity scans not used in the fitting process.

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32

Zhang, Jieyuan, Quoc P. Nguyen, Adam Flaaten, and Gary A. Pope. "Mechanisms of Enhanced Natural Imbibition With Novel Chemicals." SPE Reservoir Evaluation & Engineering 12, no. 06 (November 17, 2009): 912–20. http://dx.doi.org/10.2118/113453-pa.

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Summary A large body of literature has reflected an extensive experimental study of natural imbibition driven by local capillary pressures at high interfacial tension (IFT). However, water imbibition induced by emulsification at low IFT is not well understood. Recently, anionic surfactants have been shown to induce imbibition in mixed- and oil-wet carbonates. Sodium carbonate has been used to reduce the surfactant adsorption. However, calcium and other divalent cations can cause precipitation of the alkali unless soft water is used. This is a significant limitation of sodium carbonate. The present research both advances our understanding of the use of chemicals to enhance oil recovery (EOR) from fractured carbonate reservoirs and indicates how the process can be optimized using novel chemicals. This research applies to the improvement of oil recovery from mixed- and oil-wet fractured carbonate reservoirs. We show how to select and evaluate new chemicals as natural imbibition enhancers in carbonate rocks. A novel experimental method has also been developed to quantify the significance of capillary and emulsification driven imbibition because of the presence of the chemical imbibition enhancers. An in situ imbibition profile was visualized using a computed tomography (CT) X-ray scanning technique. The results show that formation of microemulsion strongly promotes water imbibition. The rate was highest for Winsor Type II microemulsion and lowest for Winsor Type I microemulsion. The alkalis exhibited a striking imbibition enhancement driven mainly by alteration of capillary pressure. The performance of the imbibition enhancers was found to be consistent for different core-plug sizes and boundary conditions. A novel alkali has been tested that shows a high tolerance for hardness and, thus, may be a good alternative to sodium carbonate under some conditions. The application of low-cost chemicals to EOR from fractured carbonates is an extremely significant development owing to the vast volumes of oil in such reservoirs and the lack of practical alternative methods of recovering such oil.

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33

Lewis, R. M., G. C. Emmans, G. Simm, W. S. Dingwall, and J. FitzSimons. "A description of the growth of sheep." Proceedings of the British Society of Animal Science 1998 (1998): 47. http://dx.doi.org/10.1017/s0308229600032608.

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The idea that an animal of a given kind has, and grows to, a final or mature size is a useful one and several equations have been proposed that describe such growth to maturity (Winsor, 1932; Parks, 1982; Taylor, 1982). The Gompertz is one of these growth functions and describes in a comparatively simple, single equation the sigmoidal pattern of growth. It has 3 parameters, only 2 of which are important - mature size A and the rate parameter B. Estimates of A and B, however, are highly correlated. Considering A and B as a lumped parameter (AB) may overcome this problem. A Gompertz, or any other, growth function is not expected to describe all growth curves. When the environment (e.g., feed, housing) is non-limiting, it may provide a useful and succinct description of growth. The objectives of this study were to examine: (i) if the Gompertz equation adequately describes the growth of two genotypes of sheep under conditions designed to be non-limiting; and, (ii) if the lumped parameter AB has more desirable properties for estimation than A and B separately.

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34

Khorsandi, Saeid, Changhe Qiao, and Russell T. Johns. "Simulation of Surfactant/Polymer Floods With a Predictive and Robust Microemulsion Flash Calculation." SPE Journal 22, no. 02 (October 20, 2016): 470–79. http://dx.doi.org/10.2118/179566-pa.

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Summary A compositional reservoir simulator that uses a predictive microemulsion phase-behavior model is essential for accurate estimation of oil recovery from surfactant/polymer (SP) floods. Current chemical-flooding simulators, however, use Hand's model (Hand 1939) for phase-behavior calculation. Hand's model can reasonably fit a limited set of experimental data, such as those of a salinity scan, but because it is empirical, it cannot predict phase behavior outside the matched data set. Hydrophyllic/lypophyllic difference (HLD) and net-average-curvature (NAC) equation of state (EOS) (Acosta et al. 2003) has shown great performance for tuning and prediction of experimental data. In this paper, the EOS model with the extension to two-phase regions has been incorporated for the first time into UTCHEM (2000) and our in-house general-purpose compositional simulator, PennSim (2013). All Winsor regions (Type II−, II+, III, and IV) are modeled by use of a consistent physics-based EOS model without the need for Hand's approach. The new simulator is therefore able to account correctly for gridblock properties, which can vary temporally and spatially, and significantly improve the modeling of phase behavior and oil recovery. The results show excellent agreement between UTCHEM and PennSim both in composition space and for composition/saturation profiles for the 1D simulation. The effects of varying pressure, temperature, equivalent alkane carbon number (EACN), and salinity on recoveries are demonstrated also in 1D simulations.

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35

Dong, Pengfei, Maura C. Puerto, Kun Ma, Khalid Mateen, Guangwei Ren, Gilles Bourdarot, Danielle Morel, Sibani Lisa Biswal, and George J. Hirasaki. "Ultralow-Interfacial-Tension Foam-Injection Strategy in High-Temperature Ultrahigh-Salinity Fractured Oil-Wet Carbonate Reservoirs." SPE Journal 24, no. 06 (August 8, 2019): 2822–40. http://dx.doi.org/10.2118/190259-pa.

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Summary Oil recovery in many carbonate reservoirs is challenging because of unfavorable conditions, such as oil–wet surface wettability, high reservoir heterogeneity, and high brine salinity. We present the feasibility and injection–strategy investigation of ultralow–interfacial–tension (IFT) foam in a high–temperature (greater than 80°C), ultrahigh–formation–salinity [greater than 23% total dissolved solids (TDS)] fractured oil–wet carbonate reservoir. Because a salinity gradient is generated between injection seawater (SW) (4.2% TDS) and formation brine (FB) (23% TDS), a frontal–dilution map was created to simulate frontal–displacement processes and thereafter it was used to optimize surfactant formulations. IFT measurements and bulk–foam tests were also conducted to study the salinity–gradient effect on the performance of ultralow–IFT foam. Ultralow–IFT foam–injection strategies were investigated through a series of coreflood experiments in both homogeneous and fractured oil–wet core systems with initial oil/brine two–phase saturation. The representative fractured system included a well–defined fracture by splitting the core sample lengthwise. A controllable initial oil/brine saturation in the matrix can be achieved by closing the fracture with a rubber sheet at high confining pressure. The surfactant formulation achieved ultralow IFT (magnitude of 10−2 to 10−3 mN/m) with the crude oil at the displacement front and good foamability at underoptimal conditions. Both ultralow–IFT and foamability properties were found to be sensitive to the salinity gradient. Ultralow–IFT foam flooding achieved more than 50% incremental oil recovery compared with waterflooding in fractured oil–wet systems because of the selective diversion of ultralow–IFT foam. This effect resulted in a crossflow near the foam front, with surfactant solution (or weak foam) primarily diverted from the fracture into the matrix before the foam front, and oil/high–salinity brine flowing back to the fracture ahead of the front. The crossflow of oil/high–salinity brine from the matrix to the fracture was found to create challenges for foam propagation in the fractured system by forming Winsor II conditions near the foam front and hence killing the existing foam. It is important to note that Winsor II conditions should be avoided in the ultralow–IFT foam process to ensure good foam propagation and high oil–recovery efficiency. Results in this work contributed to demonstrating the technical feasibility of ultralow–IFT foam in high–temperature, ultrahigh–salinity fractured oil–wet carbonate reservoirs and investigated the injection strategy to enhance the low–IFT foam performance. The ultralow–IFT formulation helped to mobilize the residual oil for better displacement efficiency and reduce the unfavorable capillary entry pressure for better sweep efficiency. The selective diversion of foam makes it a good candidate for a mobility–control agent in a fractured system for better sweep efficiency.

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36

Pan, Tao, Zhilong Wang, Jian-He Xu, Zhenqiang Wu, and Hanshi Qi. "Stripping of nonionic surfactants from the coacervate phase of cloud point system for lipase separation by Winsor II microemulsion extraction with the direct addition of alcohols." Process Biochemistry 45, no. 5 (May 2010): 771–76. http://dx.doi.org/10.1016/j.procbio.2010.01.019.

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37

Widyaningsih, Ratna. "Pengaruh Konsentrasi Surfaktan Anionik Terhadap Salinitas Optimum dalam Mikroemulsi Spontan dengan Sample Minyak Lapangan M." Jurnal Mineral, Energi dan Lingkungan 1, no. 1 (April 26, 2017): 60. http://dx.doi.org/10.31315/jmel.v1i1.1774.

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Formulasi optimum untuk injeksi kimia dapat ditentukan baik dengan pengukuran tegangan antarmuka yang minimum atau dengan uji perilaku daerah 3 fasa. Terkait dengan kurva desaturasi, dimana semakin rendah tegangan antarmuka, maka semakin rendah saturasi minyak sisa. Mikroemulsi tipe III berdasarkan klasifikasi Winsor adalah kondisi dimana tegangan antarmuka berada di posisi terendah dibandingkan dengan tipe I dan tipe II, dimana kondisi ini disebut juga salinitas optimum. Salinitas optimum sangat dipengaruhi oleh interaksi kimia antara surfaktan-minyak dan surfaktan-air. Terkait dengan gradient salinity pada desain injeksi surfaktan, maka target salinitas optimum yang diharapkan haruslah tercapai untuk mengoptimalkan perolehan minyak. Uji kelakuan fasa dengan menggunakan surfaktan anionik dan contoh minyak dari Lapangan M, dilakukan untuk meneliti pengaruh konsentrasi surfaktan terhadap salinitas optimum dan rasio kelarutan air/minyak di dalam mikroemulsi. Pada penelinitian ini, konsentrasi surfaktan anionik percobaan diubah dari 1 wt% menjadi 0,5 wt%. Dari dasil uji coba tersebut, menunjukkan bahwa pengurangan konsentrasi surfaktan anionik menghasilkan penurunan salinitas optimum dari 42.000 ppm menjadi 31.000 ppm. Sedangkan solubilization ratio menunjukkan hasil tidak mengalami perubahan yang signifikan. Dari hasil penelitian ini, diharapkan penggunaan konsentrasi surfaktan yang tepat akan menjadi petunjuk dalam desain injeksi surfaktan yang diharapkan sesuai dengan kondisi salinitas alami air formasi di Lapangan M.

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38

Roshanfekr, M., R. T. T. Johns, M. Delshad, and G. A. A. Pope. "Modeling of Pressure and Solution Gas for Chemical Floods." SPE Journal 18, no. 03 (January 30, 2013): 428–39. http://dx.doi.org/10.2118/147473-pa.

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Summary The goal of surfactant/polymer (SP) flooding is to reduce interfacial tension (IFT) between oil and water so that residual oil is mobilized and high recovery is achieved. The optimal salinity and optimal solubilization ratios that correspond to ultralow IFT have recently been shown, in some cases, to be a strong function of the methane mole fraction in the oil at reservoir pressure. We incorporate a recently developed methodology to determine the optimal salinity and solubilization ratio at reservoir pressure into a chemical-flooding simulator (UTCHEM). The proposed method determines the optimal conditions on the basis of density estimates by use of a cubic equation of state (EOS) and measured phase-behavior data at atmospheric pressure. The microemulsion phase-behavior (Winsor I, II, and III) are adjusted on the basis of this predicted optimal salinity and solubilization ratio in the simulator. Parameters for the surfactant phase-behavior equation are modified to account for these changes, and the trend in the equivalent alkane carbon number (EACN) is automatically adjusted for pressure and methane content in each simulation gridblock. We use phase-behavior data from several potential SP floods to demonstrate the new implementation. The implementation of the new phase-behavior model into a chemical-flooding simulator allows for a better design of SP floods and more-accurate estimations of oil recovery. The new approach could also be used to handle free gas that may form in the reservoir; however, the SP-flood simulation when free gas is present is not the focus of this paper. We show that not accounting for the phase-behavior changes that occur when methane is present at reservoir pressure can greatly affect the oil recovery of SP floods. Improper design of an SP flood can lead to production of more oil as a microemulsion phase than as an oil bank. This paper describes the procedure to implement the effect of pressure and solution gas on microemulsion phase behavior in a chemical-flooding simulator, which requires the phase-behavior data measured at atmospheric pressure.

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Puerto, Maura C., George J. Hirasaki, Clarence A. Miller, Carmen Reznik, Sheila Dubey, Julian R. Barnes, and Sjoerd van Kuijk. "Effects of Hardness and Cosurfactant on Phase Behavior of Alcohol-Free Alkyl Propoxylated Sulfate Systems." SPE Journal 20, no. 05 (October 20, 2015): 1145–53. http://dx.doi.org/10.2118/169096-pa.

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Summary The effect of hardness was investigated on equilibrium phase behavior in the absence of alcohol for blends of three alcohol propoxy sulfates (APSs) with an internal olefin sulfonate (IOS) with a C15–18 chain length. Hard brines investigated were synthetic seawater (SW), 2*SW, and 3*SW, the last two with double and triple the total ionic content of SW with all ions present in the same relative proportions as in SW, respectively. Optimal blends of the APS/IOS systems formed microemulsions with n-octane that had high solubilization suitable for enhanced oil recovery at both ≈25°C and 50°C. However, oil-free aqueous solutions of the optimal blends in 2*SW and 3*SW, as well as in 8 and 12% NaCl solutions with similar ionic strengths, exhibited cloudiness and/or precipitation and were unsuitable for injection. In SW at 25°C, the aqueous solution of the optimal blend of C16–17 7 propylene oxide sulfate, made from a branched alcohol, and IOS15–18, was clear and suitable for injection. A salinity map prepared for blends of these surfactants illustrates how such maps facilitate the selection of injection compositions in which injection and reservoir salinities differ. The same APS was blended with other APSs and alcohol ethoxy sulfates (AESs) in SW at ≈25°C, yielding microemulsions with high n-octane solubilization and clear aqueous solutions at optimal conditions. Three APS/AES blends were found to form suitable microemulsions in SW with a crude oil at its reservoir temperature near 50°C. Optimal conditions were nearly the same for hard brines and NaCl solutions with similar ionic strengths between SW and 3*SW. Although the aqueous solutions for the optimal blends with crude oil were slightly cloudy, small changes in blend ratio led to formation of lower phase microemulsions with clear aqueous solutions. When injection and reservoir brines differ, it may be preferable to inject at such slightly underoptimum conditions to avoid generating upper phase, Winsor II, conditions produced by inevitable mixing of injected and formation brines.

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40

Wells, R. J. "Phase II window therapy." Journal of Clinical Oncology 13, no. 1 (January 1995): 302–3. http://dx.doi.org/10.1200/jco.1995.13.1.302.

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41

Bernardini, Riccardo, and Jelena Kovačević. "Local orthogonal bases II: Window design." Multidimensional Systems and Signal Processing 7, no. 3-4 (July 1996): 371–99. http://dx.doi.org/10.1007/bf01826248.

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42

RICE, A. HUGH N., and MARK W. ANDERSON. "Restoration of the external Scandinavian Caledonides." Geological Magazine 153, no. 5-6 (July 13, 2016): 1136–65. http://dx.doi.org/10.1017/s0016756816000340.

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AbstractThree models are evaluated for restoring basement rocks coring tectonic windows (Window-Basement) in the Scandinavian Caledonides; parautochthonous (Model I) and allochthonous (models II/III), with initial imbrication of the Window-Basement post-dating or pre-dating, respectively, that in the external imbricate zone (Lower Allochthon). In Model I, the Window-Basement comes from the eastern margin of the basin now imbricated into the Lower Allochthon, while in models II/III it comes from the western margin. In Model II, the Window-Basement formed a basement-high between Tonian and Cryogenian sediments imbricated into the Middle and Lower allochthons; in Model III deposition of the Lower Allochthon sediments commenced in Ediacaran times. Balanced cross-sections and branch-line restorations of four transects (Finnmark–Troms, Västerbotten–Nordland, Jämtland–Trøndelag, Telemark–Møre og Romsdal) show similar restored lengths for the models in two transects and longer restorations for models II/III in the other transects. Model I can result inc.280 km wide gaps in the restored Lower Allochthon, evidence for which is not seen in the sedimentology. The presence of <3 km thick alluvial-fan deposits at the base of the Middle Allochthon indicates proximal, rapidly uplifting basement during Tonian–Cryogenian periods, taken as the origin of the Window-Basement during thrusting in models II/III. Model I requires multiple changes in thrusting-direction and predicts major thrusts or back-thrusts, currently unrecognized, separating parts of the Lower Allochthon; neither are required in models II/III. Metamorphic data are consistent with models II/III. Despite considerable along-strike structural variability in the external Scandinavian Caledonides, models II/III are preferred for the restoration of the Window-Basement.

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He, Wenlong, Chao Wen, and Xiaoyu Wang. "Occupational Exposure of Medical Staff of a Tianjin Grade 3 Hospital to Human Immunodeficiency Virus in 2013–2015." Infection International 4, no. 2 (June 1, 2015): 55–58. http://dx.doi.org/10.1515/ii-2017-0107.

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Abstract Purpose: This study aims to gain insights into occupational exposure of medical staff to human immunodeficiency virus (HIV) and to provide effective precautionary measures to protect them against risks arising from blood-borne pathogens. Methodology: Data on 46 confirmed HIV-infected patients were analyzed statistically. Results: Medical staff were exposed to blood-borne pathogens in 45 cases, and most were female and probationary nurses. Risks of occupational exposure of medical staff to HIV increased continuously as more HIV-infected patients were admitted by hospitals each year. Conclusion: Medical staff should receive information about HIV blood-borne pathogen infection of patients, shorten the window period for HIV exposure, and practice specified precautionary measures and cut down risks of exposure to HIV.

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44

Song, Ruitian, Ralf B. Loeffler, and Claudia M. Hillenbrand. "QUIPSS II with window-sliding saturation sequence (Q2WISE)." Magnetic Resonance in Medicine 67, no. 4 (September 27, 2011): 1127–32. http://dx.doi.org/10.1002/mrm.23093.

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45

Kynta, Reuben Lamiaki, Sanjib Rawat, Shyam KS Thingnam, Rohit Kumar Manoj, and Ashwani Kumar Sharma. "Type II aortopulmonary window with tetralogy of Fallot: successful repair." Asian Cardiovascular and Thoracic Annals 27, no. 2 (July 9, 2018): 110–13. http://dx.doi.org/10.1177/0218492318788166.

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Aortopulmonary window associated with tetralogy of Fallot is a rare cardiac anomaly. An 8-month-old boy presented with failure to thrive and recurrent chest infections. Echocardiography and imaging studies revealed a type II aortopulmonary window with tetralogy of Fallot. Corrective surgery in the form of patch closure of the aortopulmonary window and intracardiac repair of tetralogy of Fallot was carried out successfully.

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46

Lager, Joanne J., Elizabeth R. Lyden, James R. Anderson, Alberto S. Pappo, William H. Meyer, and Philip P. Breitfeld. "Pooled Analysis of Phase II Window Studies in Children With Contemporary High-Risk Metastatic Rhabdomyosarcoma: A Report From the Soft Tissue Sarcoma Committee of the Children's Oncology Group." Journal of Clinical Oncology 24, no. 21 (July 20, 2006): 3415–22. http://dx.doi.org/10.1200/jco.2005.01.9497.

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Purpose The Soft Tissue Sarcoma Committee of the Children's Oncology Group has conducted five upfront window trials in patients with newly diagnosed metastatic rhabdomyosarcoma to identify promising new treatment agents. Patients and Methods This pooled analysis identified a total of 420 patients (115 from Intergroup Rhabdomyosarcoma Study III [IRS-III] and 305 from the five window trials). We assessed window therapy response rate, failure-free survival (FFS), and overall survival (OS). Results Response rates (complete + partial response) assessed at week 6 of window therapy ranged from 41% to 55% and did not predict FFS (P = .073) or OS (P = .31). FFS was influenced by trial (P = .048); patients enrolled onto IRS-III and the ifosfamide/etoposide and ifosfamide/doxorubicin trials fared best. When grouped and compared with topoisomerase I poison trials, ifosfamide/topoisomerase II inhibitor trials had superior FFS (P = .013). However, there was no difference in survival. Conclusion Upfront phase II window trials can efficiently provide robust estimates of activity for new agents and combinations in newly diagnosed patients with high-risk rhabdomyosarcoma. Our data indicate that, for some phase II window trials, the risk of treatment failure may be increased but that the trend towards lower survival for some of the window trials compared with IRS-III is not statistically significant. Window nonresponders did not suffer worse FFS or OS than patients who responded to window therapy. Finally, these results provide a rationale for incorporating ifosfamide, etoposide, doxorubicin, and topoisomerase I poisons in future trials of high-risk metastatic rhabdomyosarcoma.

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WILLIAMS, DEANNE. "‘WILL YOU GO, ANHEERS?’ THE MERRY WIVES OF WINDSOR , II. i. 209." Notes and Queries 46, no. 2 (June 1, 1999): 233–34. http://dx.doi.org/10.1093/nq/46-2-233.

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WILLIAMS, DEANNE. "‘WILL YOU GO, ANHEERS?’ THE MERRY WIVES OF WINDSOR, II. i. 209." Notes and Queries 46, no. 2 (1999): 233–34. http://dx.doi.org/10.1093/nq/46.2.233.

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Wang, Feifei, Hao Wan, Zhuoran Ma, Yeteng Zhong, Qinchao Sun, Ye Tian, Liangqiong Qu, et al. "Light-sheet microscopy in the near-infrared II window." Nature Methods 16, no. 6 (May 13, 2019): 545–52. http://dx.doi.org/10.1038/s41592-019-0398-7.

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Huang, Yuan-Chang, Tai-Zan Wang, Ta-Jo Liu, and Carlos Tiu. "Operating window of solution casting. II. Non-Newtonian fluids." Journal of Applied Polymer Science 132, no. 5 (September 3, 2014): n/a. http://dx.doi.org/10.1002/app.41411.

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