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Sample records for surfactant flooding process

  1. Enhanced Oil Recovery with Surfactant Flooding

    DEFF Research Database (Denmark)

    Sandersen, Sara Bülow

    Enhanced oil recovery (EOR) is being increasingly applied in the oil industry and several different technologies have emerged during, the last decades in order to optimize oil recovery after conventional recovery methods have been applied. Surfactant flooding is an EOR technique in which the phase...... both for complex surfactant systems as well as for oil and brine systems. It is widely accepted that an increase in oil recovery can be obtained through flooding, whether it is simple waterflooding, waterflooding where the salinity has been modified by the addition or removal of specific ions (socalled...... “smart” waterflooding) or surfactant flooding. High pressure experiments have been carried out in this work on a surfactant system (surfactant/ oil/ brine) and on oil/ seawater systems (oil/ brine). The high pressure experiments were carried out on a DBR JEFRI PVT cell, where a glass window allows...

  2. Single well surfactant test to evaluate surfactant floods using multi tracer method

    Science.gov (United States)

    Sheely, Clyde Q.

    1979-01-01

    Data useful for evaluating the effectiveness of or designing an enhanced recovery process said process involving mobilizing and moving hydrocarbons through a hydrocarbon bearing subterranean formation from an injection well to a production well by injecting a mobilizing fluid into the injection well, comprising (a) determining hydrocarbon saturation in a volume in the formation near a well bore penetrating formation, (b) injecting sufficient mobilizing fluid to mobilize and move hydrocarbons from a volume in the formation near the well bore, and (c) determining the hydrocarbon saturation in a volume including at least a part of the volume of (b) by an improved single well surfactant method comprising injecting 2 or more slugs of water containing the primary tracer separated by water slugs containing no primary tracer. Alternatively, the plurality of ester tracers can be injected in a single slug said tracers penetrating varying distances into the formation wherein the esters have different partition coefficients and essentially equal reaction times. The single well tracer method employed is disclosed in U.S. Pat. No. 3,623,842. This method designated the single well surfactant test (SWST) is useful for evaluating the effect of surfactant floods, polymer floods, carbon dioxide floods, micellar floods, caustic floods and the like in subterranean formations in much less time and at much reduced cost compared to conventional multiwell pilot tests.

  3. Comparison of oil removal in surfactant alternating gas with water alternating gas, water flooding and gas flooding in secondary oil recovery process

    OpenAIRE

    Salehi, Mehdi Mohammad; Safarzadeh, Mohammad Amin; Sahraei, Eghbal; Nejad, Seyyed Alireza Tabatabaei

    2014-01-01

    Growing oil prices coupled with large amounts of residual oil after operating common enhanced oil recovery methods has made using methods with higher operational cost economically feasible. Nitrogen is one of the gases used in both miscible and immiscible gas injection process in oil reservoir. In heterogeneous formations gas tends to breakthrough early in production wells due to overriding, fingering and channeling. Surfactant alternating gas (SAG) injection is one of the methods commonly us...

  4. BENCH-SCALE VISUALIZATION OF DNAPL REMEDIATION PROCESSES IN ANALOG HETEROGENEOUS AQUIFERS: SURFACTANT FLOODS, AND IN SITU OXIDATION USING PERMANGANATE

    Science.gov (United States)

    We have conducted well-controlled DNAPL remediation experiments using surfactants (Aerosol MA and Tween 80) to increase solubility and an oxidant (permanganate) to chemically degrade the DNAPL. Photographs and digital image analysis illustrate previously unobserved interactions b...

  5. NUMERICAL SIMULATION AND FIELD IMPLEMENTATION OF SURFACTANT FLOODING

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Based on the features of surfactant flooding, a mathematical model for surfactant flooding is established. The adsorption-retention, convection diffusion of surfactant and influence of concentration change upon relative permeability curve are included in the model. The novel description of adsorption quantity of surfactant and relative permeability curve are presented, which enhance the coincidence between mathematical model and field practice, the relative errors of main development indexes are within 6%. The model is applied to the numerical research of the surfactant flooding in the untabulated beds of Xing1-3 surfactant flooding pilot site of No.4 Oil Production Company of Daqing Oilfield, the influences of surfactant concentration, injection quantity, slug combination mode upon the development effect and economic benefit are quantitatively analyzed, the injection scheme is optimized as follows: surfactant concentration is 0.5%, slug volume is 0.02 PV, slug combination mode is 2 slugs. After the implementation of scheme in oilfield, the cumulative increase of oil is 2186.0 t, up to nearly 30%.

  6. Performance improvement of ionic surfactant flooding in carbonate rock samples by use of nanoparticles

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Ahmadi

    2016-07-01

    Full Text Available Abstract Various surfactants have been used in upstream petroleum processes like chemical flooding. Ultimately, the performance of these surfactants depends on their ability to reduce the interfacial tension between oil and water. The surfactant concentration in the aqueous solution decreases owing to the loss of the surfactant on the rock surface in the injection process. The main objective of this paper is to inhibit the surfactant loss by means of adding nanoparticles. Sodium dodecyl sulfate and silica nanoparticles were used as ionic surfactant and nanoparticles in our experiments, respectively. AEROSIL® 816 and AEROSIL® 200 are hydrophobic and hydrophilic nanoparticles. To determine the adsorption loss of the surfactant onto rock samples, a conductivity approach was used. Real carbonate rock samples were used as the solid phase in adsorption experiments. It should be noted that the rock samples were water wet. This paper describes how equilibrium adsorption was investigated by examining adsorption behavior in a system of carbonate sample (solid phase and surfactant solution (aqueous phase. The initial surfactant and nanoparticle concentrations were 500–5000 and 500–2000 ppm, respectively. The rate of surfactant losses was extremely dependent on the concentration of the surfactant in the system, and the adsorption of the surfactant decreased with an increase in the nanoparticle concentration. Also, the hydrophilic nanoparticles are more effective than the hydrophobic nanoparticles.

  7. Next Generation Surfactants for Improved Chemical Flooding Technology

    Energy Technology Data Exchange (ETDEWEB)

    Laura Wesson; Prapas Lohateeraparp; Jeffrey Harwell; Bor-Jier Shiau

    2012-05-31

    The principle objective of this project was to characterize and test current and next generation high performance surfactants for improved chemical flooding technology, focused on reservoirs in the Pennsylvanian-aged (Penn) sands. In order to meet this objective the characteristic curvatures (Cc) of twenty-eight anionic surfactants selected for evaluation for use in chemical flooding formulations were determined. The Cc values ranged from -6.90 to 2.55 with the majority having negative values. Crude oil samples from nine Penn sand reservoirs were analyzed for several properties pertinent to surfactant formulation for EOR application. These properties included equivalent alkane carbon numbers, total acid numbers, and viscosity. The brine samples from these same reservoirs were analyzed for several cations and for total dissolved solids. Surfactant formulations were successfully developed for eight reservoirs by the end of the project period. These formulations were comprised of a tertiary mixture of anionic surfactants. The identities of these surfactants are considered proprietary, but suffice to say the surfactants in each mixture were comprised of varying chemical structures. In addition to the successful development of surfactant formulations for EOR, there were also two successful single-well field tests conducted. There are many aspects that must be considered in the development and implementation of effective surfactant formulations. Taking into account these other aspects, there were four additional studies conducted during this project. These studies focused on the effect of the stability of surfactant formulations in the presence of polymers with an associated examination of polymer rheology, the effect of the presence of iron complexes in the brine on surfactant stability, the potential use of sacrificial agents in order to minimize the loss of surfactant to adsorption, and the effect of electrolytes on surfactant adsorption. In these last four studies

  8. NUMERICAL SIMULATION STUDY ON SURFACTANT FLOODING FOR LOW PERMEABILITY OILFIELD IN THE CONDITION OF THRESHOLD PRESSURE

    Institute of Scientific and Technical Information of China (English)

    YIN Dai-yin; PU Hui

    2008-01-01

    Based on the non-Darcy flow characteristics of surfactant flooding in the low permeability oilfield, considering the changes of threshold pressure and influence of surfactant on convection, diffusion, adsorption and retention, a mathematical model is established for a three-dimensional, two-phase, three-component surfactant flooding. A new treatment for the changes of threshold pressure and a novel correction method for the relative permeability curve in the process of surfactant flooding are derived, which enhances the matching degree between the mathematical model and field practice. The mathematical model was used to perform the numerical simulation study for a pilot test of surfactant flooding in Chao 45 Block of Daqing Oilfield, a proper injection plan was optimized. After the optimized plan was carried out in oilfield, the desirable effects, like pressure-reducing, injection rate increase, and the increase of oil recovery, were achieved. The average oil increase for single well reaches 37%, the ratio of cost to revenue is above 1:4, so the economic effect of scale is promising.

  9. Study on the reutilization of clear fracturing flowback fluids in surfactant flooding with additives for Enhanced Oil Recovery (EOR.

    Directory of Open Access Journals (Sweden)

    Caili Dai

    Full Text Available An investigation was conducted to study the reutilization of clear fracturing flowback fluids composed of viscoelastic surfactants (VES with additives in surfactant flooding, making the process more efficient and cost-effective. The clear fracturing flowback fluids were used as surfactant flooding system with the addition of α-olefin sulfonate (AOS for enhanced oil recovery (EOR. The interfacial activity, emulsification activity and oil recovery capability of the recycling system were studied. The interfacial tension (IFT between recycling system and oil can be reduced by 2 orders of magnitude to 10(-3 mN/m, which satisfies the basic demand of surfactant flooding. The oil can be emulsified and dispersed more easily due to the synergetic effect of VES and AOS. The oil-wet surface of quartz can be easily converted to water-wet through adsorption of surfactants (VES/AOS on the surface. Thirteen core plug flooding tests were conducted to investigate the effects of AOS concentrations, slug sizes and slug types of the recycling system on the incremental oil recovery. The investigations prove that reclaiming clear fracturing flowback fluids after fracturing operation and reuse it in surfactant flooding might have less impact on environment and be more economical.

  10. Study on the reutilization of clear fracturing flowback fluids in surfactant flooding with additives for Enhanced Oil Recovery (EOR).

    Science.gov (United States)

    Dai, Caili; Wang, Kai; Liu, Yifei; Fang, Jichao; Zhao, Mingwei

    2014-01-01

    An investigation was conducted to study the reutilization of clear fracturing flowback fluids composed of viscoelastic surfactants (VES) with additives in surfactant flooding, making the process more efficient and cost-effective. The clear fracturing flowback fluids were used as surfactant flooding system with the addition of α-olefin sulfonate (AOS) for enhanced oil recovery (EOR). The interfacial activity, emulsification activity and oil recovery capability of the recycling system were studied. The interfacial tension (IFT) between recycling system and oil can be reduced by 2 orders of magnitude to 10(-3) mN/m, which satisfies the basic demand of surfactant flooding. The oil can be emulsified and dispersed more easily due to the synergetic effect of VES and AOS. The oil-wet surface of quartz can be easily converted to water-wet through adsorption of surfactants (VES/AOS) on the surface. Thirteen core plug flooding tests were conducted to investigate the effects of AOS concentrations, slug sizes and slug types of the recycling system on the incremental oil recovery. The investigations prove that reclaiming clear fracturing flowback fluids after fracturing operation and reuse it in surfactant flooding might have less impact on environment and be more economical.

  11. Development of cost-effective surfactant flooding technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pope, G.A.; Sepehrnoori, K.

    1996-11-01

    Task 1 of this research was the development of a high-resolution, fully implicit, finite-difference, multiphase, multicomponent, compositional simulator for chemical flooding. The major physical phenomena modeled in this simulator are dispersion, heterogeneous permeability and porosity, adsorption, interfacial tension, relative permeability and capillary desaturation, compositional phase viscosity, compositional phase density and gravity effects, capillary pressure, and aqueous-oleic-microemulsion phase behavior. Polymer and its non-Newtonian rheology properties include shear-thinning viscosity, permeability reduction, inaccessible pore volume, and adsorption. Options of constant or variable space grids and time steps, constant-pressure or constant-rate well conditions, horizontal and vertical wells, and multiple slug injections are also available in the simulator. The solution scheme used in this simulator is fully implicit. The pressure equation and the mass-conservation equations are solved simultaneously for the aqueous-phase pressure and the total concentrations of each component. A third-order-in-space, second-order-in-time finite-difference method and a new total-variation-diminishing (TVD) third-order flux limiter are used that greatly reduce numerical dispersion effects. Task 2 was the optimization of surfactant flooding. The code UTCHEM was used to simulate surfactant polymer flooding.

  12. Development of cost-effective surfactant flooding technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Pope, G.A.; Sepehrnoori, K.

    1996-11-01

    Task 1 of this research was the development of a high-resolution, fully implicit, finite-difference, multiphase, multicomponent, compositional simulator for chemical flooding. The major physical phenomena modeled in this simulator are dispersion, heterogeneous permeability and porosity, adsorption, interfacial tension, relative permeability and capillary desaturation, compositional phase viscosity, compositional phase density and gravity effects, capillary pressure, and aqueous-oleic-microemulsion phase behavior. Polymer and its non-Newtonian rheology properties include shear-thinning viscosity, permeability reduction, inaccessible pore volume, and adsorption. Options of constant or variable space grids and time steps, constant-pressure or constant-rate well conditions, horizontal and vertical wells, and multiple slug injections are also available in the simulator. The solution scheme used in this simulator is fully implicit. The pressure equation and the mass-conservation equations are solved simultaneously for the aqueous-phase pressure and the total concentrations of each component. A third-order-in-space, second-order-in-time finite-difference method and a new total-variation-diminishing (TVD) third-order flux limiter are used that greatly reduce numerical dispersion effects. Task 2 was the optimization of surfactant flooding. The code UTCHEM was used to simulate surfactant polymer flooding.

  13. Small core flood experiments for foam EOR: screening surfactant applications

    NARCIS (Netherlands)

    Jones, S.A.; Van der Bent, V.; Farajzadeh, R.; Rossen, W.R.; Vincent-Bonnieu, S.

    2015-01-01

    Aqueous foams are a means of increasing the sweep efficiency of enhanced oil recovery processes. An understanding of how a foam behaves in the presence of oil is therefore of great importance when selecting suitable surfactants for EOR processes. The consensus is currently that the most reliable met

  14. Research on surfactant flooding in high temperature and high-salinity reservoir for enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ming [Southwest Petroleum Univ., Chengdu, Sichuan (China). State Key Lab. of Oil and Gas Reservoir Geology and Exploitation; Southwest Petroleum Univ., Chengdu, Sichuan (China). School of Material Science and Engineering; Zhao, Jinzhou; Yang, Yan [Southwest Petroleum Univ., Chengdu, Sichuan (China). State Key Lab. of Oil and Gas Reservoir Geology and Exploitation; Wang, Xu [Southwest Petroleum Univ., Chengdu, Sichuan (China). School of Material Science and Engineering

    2013-05-15

    The aim of this work was to research the solution properties of a new surfactant flooding system for high temperature and high salinity reservoir, which include trimeric sulfonate surfactants 1,2,3-tri(2-oxypropyl sulfonation-3-alkylether-propoxyl) propanes (TTSS-n) and anion-nonionic surfactant NPSO [sodium nonyl phenol polyethyleneoxy ether sulfonate, (EO = 10)]. The critical micelle concentrations (CMCs) of five trimeric sulfonate surfactants were smaller than 400 mg L{sup -1}. Furthermore, their interfacial tensions (IFTs) could reach an ultralow value with Tazhong 4 oil at lower concentrations. Through optimized formulation, we found that TTSS-12 had better properties and was selected as the major component of the surfactant flooding system. We designed an optimal formulation of the surfactant flooding system with 1000 mg . L{sup -1} TTSS-12 and 1000 mg . L{sup -1} NPSO surfactant. The system with a very small surfactant concentration could reach ultralow IFT with Tazhong 4 crude oils at high temperature (110 C) and high concentration formation brine (112,228.8 mg/L TDS), which proved that the simpler component surfactant had better reservoir compatibility. NPSO could weaken the disadvantage of the surfactant TTSS-12 in oil/water interface. The stability of this surfactant flooding system was evaluated by aging time, static adsorption and chromatographic separation. All experiments showed that it still keeps ultralow IFT in high temperature and high salinity conditions. Coreflooding experimentation showed that average oil recovery reached 9.8 wt% by surfactant flooding, therefore, it is feasible to use as a surfactant flooding system for enhanced oil recovery (EOR). (orig.)

  15. BEHAVIOR OF SURFACTANT MIXTURES AT SOLID/LIQUID AND OIL/LIQUID INTERFACES IN CHEMICAL FLOODING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    P. Somasundaran

    2004-11-20

    The aim of the project is to develop a knowledge base to help the design of enhanced processes for mobilizing and extracting untrapped oil. We emphasize evaluation of novel surfactant mixtures and obtaining optimum combinations of the surfactants for efficient chemical flooding EOR processes. In this regard, an understanding of the aggregate shape, size and structure is crucial since these properties govern the crude oil removal efficiency. During the three-year period, the adsorption and aggregation behavior of sugar-based surfactants and their mixtures with other types of surfactants have been studied. Sugar-based surfactants are made from renewable resources, nontoxic and biodegradable. They are miscible with water and oil. These environmentally benign surfactants feature high surface activity, good salinity, calcium and temperature tolerance, and unique adsorption behavior. They possess the characteristics required for oil flooding surfactants and have the potential for replacing currently used surfactants in oil recovery. A novel analytical ultracentrifugation technique has been successfully employed for the first time, to characterize the aggregate species present in mixed micellar solution due to its powerful ability to separate particles based on their size and shape and monitor them simultaneously. Analytical ultracentrifugation offers an unprecedented opportunity to obtain important information on mixed micelles, structure-performance relationship for different surfactant aggregates in solution and their role in interfacial processes. Initial sedimentation velocity investigations were conducted using nonyl phenol ethoxylated decyl ether (NP-10) to choose the best analytical protocol, calculate the partial specific volume and obtain information on sedimentation coefficient, aggregation mass of micelles. Four softwares: OptimaTM XL-A/XL-I data analysis software, DCDT+, Svedberg and SEDFIT, were compared for the analysis of sedimentation velocity

  16. Use of amine oxide surfactants for chemical flooding EOR (enhanced oil recovery)

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, D.K.

    1989-11-01

    The use of amine oxides with and without alcohols as cosolvents, and in combination with other surfactants as mixed micellar formulations for enhanced oil recovery by surfactant flooding was investigated. Amine oxides are a salt-tolerant class of surfactants that produce low interfacial tension and can develop viscosity without the addition of polymers. These salt-tolerant formulations generate three-phase regions with hydrocarbons over a broad salinity range, develop moderate solubilization, and produce low interfacial tensions, however oil recovery from amine oxide-alcohol phase behavior optimized formulations was directly dependent upon the quantity of surfactant injected. The large pore volume and high concentration of surfactant required prohibits their economic use as the primary surfactant in chemical flooding EOR. Dimethylalkylamine oxides are useful as cosurfactants and viscosifiers in formulations with other surfactants for chemical flooding EOR but the use of ethoxylated and propoxylated amine oxides should be avoided due to the decomposition of these amine oxides under reservoir conditions. Phase behavior, phase inversion temperatures, and viscosity scans have been correlated with surfactant structures to provide a guide for amine oxide applications in chemical flooding. 36 refs., 5 figs., 6 tabs.

  17. Development of cost-effective surfactant flooding technology. First annual report for the period, September 30, 1992--September 29, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Pope, G.A.; Sepehrnoori, K.

    1994-08-01

    This research consists of the parallel development of a new chemical flooding simulator and the application of existing UTCHEM simulation code to model surfactant flooding. The new code is based upon a completely new numerical method that combines for the first time higher order finite difference methods, flux limiters, and implicit algorithms. Early results indicate that this approach has significant advantages in some problems and will likely enable simulation of much larger and more realistic chemical floods once it is fully developed. Additional improvements have also been made to the UTCHEM code and it has been applied for the first time to the study of stochastic reservoirs with and without horizontal wells to evaluate methods to reduce the cost and risk of surfactant flooding. During the first year of this contract, significant progress has been made on both of these tasks. The authors have found that there are indeed significant differences between the performance predictions based upon the traditional layered reservoir description and the more realistic and flexible descriptions using geostatistics. These preliminary studies of surfactant flooding using horizontal wells shows that although they have significant potential to greatly reduce project life and thus improve the economics of the process, their use requires accurate reservoir descriptions and simulations to be effective. Much more needs to be done to fully understand and optimize their use and develop reliable design criteria.

  18. BEHAVIOR OF SURFACTANT MIXTURES AT SOLID/LIQUID AND OIL/LIQUID INTERFACES IN CHEMICAL FLOODING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Prof. P. Somasundaran

    2003-03-31

    The aim of the project is to develop a knowledge base to help with the design of enhanced process for mobilizing and extracting untrapped oil. We emphasize on evaluating novel surfactant mixtures and on obtaining optimum combinations of the surfactants in chemical flooding EOR process. An understanding of the micellar shape and size is crucial since these physical properties directly determine the crude oil removal efficiency. Analytical ultracentrifugation experiments were used to test the multi-micelle model proposed earlier and formulate the relationships between mixed micelle formation and the surfactant structure. Information on partial specific volume of surfactants and their mixtures is required to treat analytical ultracentrifuge data. In the last report, it was noted that the partial specific volumes of the sugar-based surfactants obtained experimentally did not agree with those from theoretical calculations. A scrutiny of partial specific volumes of the four sugar-based surfactants revealed that conformational changes upon micelle formation are responsible for the large deviation. From sedimentation equilibrium experiments, two types of micelles were identified for the nonionic polyethylene surfactant and its mixtures with the sugar-based surfactant, dodecyl maltoside. The average aggregation numbers of n-dodecyl-{beta}-D-maltoside and nonyl phenol ethoxylated decyl ether agreed with those reported in literature using other techniques. Our study displayed, for the first time, that small micelles might coexist with large micelles at high concentrations due to unique structures of the surfactant although classical thermodynamic theory supports only one type of micelle. Initial dynamic light scattering results support the results for the same mixed surfactant system from analytical ultracentrifuge equilibrium technique. The implication of this finding lies in the fact that efficiency of oil recovery will be improved due to the large micellar size, its

  19. Development of alkaline/surfactant/polymer (ASP flooding technology for recovery of Karazhanbas oil

    Directory of Open Access Journals (Sweden)

    Birzhan Zhappasbaev

    2016-03-01

    Full Text Available The tertiary oil recovery methods like alkaline, surfactant and polymer (ASP flooding are very perspective in order to achieve the synergetic effect out of the different impacts which are caused by these chemicals, which affect oil and water filtration in the reservoir and increase oil recovery. In this communication, we consider the applicability of hydrophobically modified polyampholyte – poly(hexadecylaminocrotonatebetaine (PHDACB as ASP flooding agent for recovery of oil from Karazhanbas oilfield. As “polysoap”, the aqueous solution of PHDACB dissolved in aqueous KOH was used. This system combines the advantages of alkaline, surfactant and polymer and exhibits the synergistic effect. The laboratory results showed that the ASP flooding considerably increases the oil recovery in addition to water flooding. In perspective, the ASP flooding may substitute the steam injection and other thermal enhanced oil recovery (EOR technologies.

  20. Alkali/Surfactant/Polymer Flooding in the Daqing Oilfield Class II Reservoirs Using Associating Polymer

    Directory of Open Access Journals (Sweden)

    Ru-Sen Feng

    2013-01-01

    Full Text Available Hydrophobically modified associating polyacrylamide (HAPAM has good compatibility with the Daqing heavy alkylbenzene sulfonate surfactant. The HAPAM alkali/surfactant/polymer (ASP system can generate ultralow interfacial tension in a wide range of alkali/surfactant concentrations and maintain stable viscosity and interfacial tension for 120 days. The HAPAM ASP system has good injectivity for the Daqing class II reservoirs (100–300 × 10−3 μm2 and can improve oil recovery by more than 25% on top of water flooding. In the presence of both the alkali and the surfactant, the surfactant interacts with the associating groups of the polymer to form more micelles, which can significantly enhance the viscosity of the ASP system. Compared with using HPAM (Mw = 2.5 MDa, using HAPAM can reduce the polymer use by more than 40%.

  1. Secondary oil recovery process. [two separate surfactant slugs

    Energy Technology Data Exchange (ETDEWEB)

    Fallgatter, W.S.

    1969-01-14

    Oil recovery by two separate surfactant slugs is greater than for either one alone. One slug contains a surfactant(s) in either oil or water. The other slug contains surfactant(s) in thickened water. The surfactants are sodium petroleum sulfonate (Promor SS20), polyoxyethylene sorbitan trioleate (Tween 85), lauric acid diethanolamide (Trepoline L), and sodium tridecyl sulfate polyglycol ether (Trepenol S30T). The thickener is carboxymethyl cellulose (Hercules CMC 70-S Medium thickener) or polyvinyl alcohol (Du Pont Elvanol 50-42). Consolidated sandstone cores were flooded with water, followed with Hawes crude, and finally salt water (5 percent sodium chloride) which recovered about 67 percent of the crude. A maximum of 27.5 percent of the residual oil was recovered by surfactant(s) in oil or water followed by fresh water, then surfactant(s) plus thickener in water followed by fresh water. Either surfactant slug may be injected first. Individually, each of the surfactant slugs can recover from about 3 to 11 percent less residual oil than their total recovery when used consecutively.

  2. 辽河油田稀油二元复合驱采出污水絮凝处理研究%Treatment of polymer-surfactant flooding produced water from thin oil recovery of Liaohe Oilfield by flocculation process

    Institute of Scientific and Technical Information of China (English)

    周洪义; 李润富; 赵晓非

    2012-01-01

    Using flocculation process to treat polymer-surfactant flooding produced water from thin oil recovery of Liaohe Oilfield, the proper inorganic and organic flocculant were determined; the influences of compounded flocculant and its dosing method on the flocculation effect were investigated; meanwhile, the morphologies of floes in water samples added with different flocculants were observed using microscope. The results of the test showed that, PAC and CPAM were the optimal inorganic and organic flocculant respectively, and the flocculation effect of CPAM increased with the increasing of cationic degree. The dosage of organic flocculant could greatly affect the flocculation effect of the compounded flocculant. For the said compounded flocculant, the optimal dosage of PAC and CPAM-1 were 300 and 4 mg/L respectively. After the treatment, the mass concentrations of SS and oil in the sewage were 10.65 and 2.43 mg/L respectively; the light transmittance reached 84.0%, and the floes was tight. The optimal agent dosing method was: adding organic flocculant immediately after the inorganic flocculant was added. Different flocculants produced various floes with different morphologies. The larger the CPAM-1 dosage was, the tighter the floes produced by the compounded flocculant would be.%对辽河油田稀油二元复合驱采出污水进行絮凝处理.优选了无机、有机絮凝剂,考察了复配絮凝剂效果及其加药方式对絮凝效果的影响,研究了不同絮凝剂产生的絮体形态.结果表明,优选的无机絮凝剂为聚合氯化铝(PAC),有机絮凝剂为阳离子聚丙烯酰胺(CPAM),其絮凝效果随阳离子度的提高而提高.有机絮凝剂投加量对复配絮凝剂的处理效果影响较大.适宜的复配药剂投加量为PAC 300 mg/L、CPAM-1 4 mg/L,处理后污水SS的质量浓度为10.65 mg/L、油的质量浓度为2.43 mg/L、透光率为84.0%,絮体较致密.最好的加药方式为投加完无机絮凝剂后,立即加入有机絮

  3. Surfactant-enhanced alkaline flooding for light oil recovery. Annual report, 1992--1993

    Energy Technology Data Exchange (ETDEWEB)

    Wasan, D.T.

    1994-08-01

    In this report, the authors present the results of experimental and theoretical studies in surfactant-enhanced alkaline flooding for light oil recovery. The overall objective of this work is to develop a very cost-effective method for formulating a successful surfactant-enhanced alkaline flood by appropriately choosing mixed alkalis which form inexpensive buffers to obtain the desired pH (between 8.5 and 12.0) for ultimate spontaneous emulsification and ultralow interfacial tension. In addition, the authors have (1) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, (2) investigated the mechanisms for spontaneous emulsification, (3) developed a technique to monitor low water content in oil, and (4) developed a technique to study water-in-oil emulsion film properties.

  4. Model study of enhanced oil recovery by flooding with aqueous surfactant solution and comparison with theory.

    Science.gov (United States)

    Fletcher, Paul D I; Savory, Luke D; Woods, Freya; Clarke, Andrew; Howe, Andrew M

    2015-03-17

    With the aim of elucidating the details of enhanced oil recovery by surfactant solution flooding, we have determined the detailed behavior of model systems consisting of a packed column of calcium carbonate particles as the porous rock, n-decane as the trapped oil, and aqueous solutions of the anionic surfactant sodium bis(2-ethylhexyl) sulfosuccinate (AOT). The AOT concentration was varied from zero to above the critical aggregation concentration (cac). The salt content of the aqueous solutions was varied to give systems of widely different, post-cac oil-water interfacial tensions. The systems were characterized in detail by measuring the permeability behavior of the packed columns, the adsorption isotherms of AOT from the water to the oil-water interface and to the water-calcium carbonate interface, and oil-water-calcium carbonate contact angles. Measurements of the percent oil recovery by pumping surfactant solutions into calcium carbonate-packed columns initially filled with oil were analyzed in terms of the characterization results. We show that the measured contact angles as a function of AOT concentration are in reasonable agreement with those calculated from values of the surface energy of the calcium carbonate-air surface plus the measured adsorption isotherms. Surfactant adsorption onto the calcium carbonate-water interface causes depletion of its aqueous-phase concentration, and we derive equations which enable the concentration of nonadsorbed surfactant within the packed column to be estimated from measured parameters. The percent oil recovery as a function of the surfactant concentration is determined solely by the oil-water-calcium carbonate contact angle for nonadsorbed surfactant concentrations less than the cac. For surfactant concentrations greater than the cac, additional oil removal occurs by a combination of solubilization and emulsification plus oil mobilization due to the low oil-water interfacial tension and a pumping pressure increase.

  5. Surfactant-enhanced alkaline flooding for light oil recovery. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wasan, D.T.

    1996-05-01

    In this report, we present the results of our experimental and theoretical studies in surfactant-enhanced alkaline flooding for light oil recovery. The overall objective of this work is to develop a very cost-effective method for formulating a successful surfactant-enhanced alkaline flood by appropriately choosing mixed alkalis which form inexpensive buffers to obtain the desired pH (between 8.5 and 12. 0) for ultimate spontaneous emulsification and ultralow interfacial tension. In addition, we have (1) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, (2) investigated the mechanisms for spontaneous emulsification, (3) developed a technique to monitor low water content in oil and (4) developed a technique to study water-in-oil emulsion film properties, (5) investigated the effect of surfactant on the equilibrium and transient interfacial tension, (6) investigated the kinetics of oil removal from a silica surface, and (7) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, accounting for added surfactant. The results of the studies conducted during the course of this project are discussed.

  6. Surfactant-enhanced alkaline flooding for light oil recovery. Final report 1994--1995

    Energy Technology Data Exchange (ETDEWEB)

    Wasan, D.T.

    1995-12-01

    In this report, the authors present the results of their experimental and theoretical studies in surfactant-enhanced alkaline flooding for light oil recovery. The overall objective of this work is to develop a very cost-effective method for formulating a successful surfactant-enhanced alkaline flood by appropriately choosing mixed alkalis which form inexpensive buffers to obtain the desired pH (between 8.5 and 12.0) for ultimate spontaneous emulsification and ultralow interfacial tension. In addition, the authors have (1) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, (2) investigated the mechanisms for spontaneous emulsification, (3) developed a technique to monitor low water content in oil, and (4) developed a technique to study water-in-oil emulsion film properties, (5) investigated the effect of surfactant on the equilibrium and transient interfacial tension, (6) investigated the kinetics of oil removal from a silica surface, and (7) developed a theoretical interfacial activity model for determining equilibrium interfacial tension, accounting for added surfactant. The results of the studies conducted during the course of this project are summarized.

  7. Modeling and simulation of surfactant-polymer flooding using a new hybrid method

    Science.gov (United States)

    Daripa, Prabir; Dutta, Sourav

    2017-04-01

    Chemical enhanced oil recovery by surfactant-polymer (SP) flooding has been studied in two space dimensions. A new global pressure for incompressible, immiscible, multicomponent two-phase porous media flow has been derived in the context of SP flooding. This has been used to formulate a system of flow equations that incorporates the effect of capillary pressure and also the effect of polymer and surfactant on viscosity, interfacial tension and relative permeabilities of the two phases. The coupled system of equations for pressure, water saturation, polymer concentration and surfactant concentration has been solved using a new hybrid method in which the elliptic global pressure equation is solved using a discontinuous finite element method and the transport equations for water saturation and concentrations of the components are solved by a Modified Method Of Characteristics (MMOC) in the multicomponent setting. Numerical simulations have been performed to validate the method, both qualitatively and quantitatively, and to evaluate the relative performance of the various flooding schemes for several different heterogeneous reservoirs.

  8. Surfactant-enhanced alkaline flooding field project. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    French, T.R.; Josephson, C.B.

    1993-12-01

    The Tucker sand from Hepler field, Crawford County, Kansas, was characterized using routine and advanced analytical methods. The characterization is part of a chemical flooding pilot test to be conducted in the field, which is classified as a DOE Class I (fluvial-dominated delta) reservoir. Routine and advanced methods of characterization were compared. Traditional wireline logs indicate that the reservoir is vertically compartmentalized on the foot scale. Routine core analysis, X-ray computed tomography (CT), minipermeameter measurement, and petrographic analysis indicate that compartmentalization and lamination extend to the microscale. An idealized model of how the reservoir is probably structured (complex layering with small compartments) is presented. There was good agreement among the several methods used for characterization, and advanced characterization methods adequately explained the coreflood and tracer tests conducted with short core plugs. Tracer and chemical flooding tests were conducted in short core plugs while monitoring with CT to establish flow patterns and to monitor oil saturations in different zones of the core plugs. Channeling of injected fluids occurred in laboratory experiments because, on core plug scale, permeability streaks extended the full length of the core plugs. A graphic example of how channeling in field core plugs can affect oil recovery during chemical injection is presented. The small scale of compartmentalization indicated by plugs of the Tucker sand may actually help improve sweep between wells. The success of field-scale waterflooding and the fluid flow patterns observed in highly heterogeneous outcrop samples are reasons to expect that reservoir flow patterns are different from those observed with short core plugs, and better sweep efficiency may be obtained in the field than has been observed in laboratory floods conducted with short core plugs.

  9. Study to determine the technical and economic feasibility of reclaiming chemicals used in micellar polymer and low tension surfactant flooding. Final report. [Ultrafiltration membranes and reverse osmosis membranes

    Energy Technology Data Exchange (ETDEWEB)

    Stephens, R.H.; Himmelblau, A.; Donnelly, R.G.

    1978-02-01

    Energy Resources Company has developed a technology for use with enhanced oil recovery to achieve emulsion breaking and surfactant recovery. By using ultrafiltration membranes, the Energy Resources Company process can dewater an oil-in-water type emulsion expected from enhanced oil recovery projects to the point where the emulsion can be inverted and treated using conventional emulsion-treating equipment. By using a tight ultrafiltration membrane or a reverse osmosis membrane, the Energy Resources Company process is capable of recovering chemicals such as surfactants used in micellar polymer flooding.

  10. Sensitivity Analysis and Optimization of Surfactant-Polymer Flooding under Uncertainties

    Directory of Open Access Journals (Sweden)

    Douarche F.

    2014-07-01

    Full Text Available Chemical flooding is currently one of the most promising solution to increase the recovery of mature reservoirs. In Surfactant-Polymer (SP processes, several parameters should be taken into account to estimate the return on investments: concentrations of the injected chemical species, slug sizes, initiation times, residual oil saturation, adsorption rates of the chemical species on the rock, etc. Some parameters are design parameters whereas other ones are uncertain. For operators, defining the optimal values of the first ones while considering the uncertainties related to the second ones, is not an easy task in practice. This work proposes a methodology to help handle this problem. Starting from a synthetic reservoir test case where an SP process is set up, we select design and uncertain parameters which may impact the production. In the reservoir simulator, for the sake of flexibility, some of them are tabulated functions, which enables the user to input any data coming from any system. However, point-wise modifications of these curves would soar the number of parameters. Therefore, a particular parameterization is introduced. We then propose a methodology based on Response-Surface Modeling (RSM to first approximate the oil production computed by a reservoir simulator for different values of our parameters and identify the most influential ones. This RSM is based on a Karhunen-Loève decomposition of the time response of the reservoir simulator and on an approximation of the components of this decomposition by a Gaussian process. This technique allows us to obtain substantial savings of computation times when building the response surfaces. Once a good predictability is achieved, the surfaces are used to optimize the design of the SP process, taking economic parameters and uncertainties on the data into account without additional reservoir simulations.

  11. Selecting and performance evaluating of surfactant in carbon dioxide foam flooding in Caoshe oil field

    Energy Technology Data Exchange (ETDEWEB)

    Yi, X.; Zhang, S.; Lu, Y.; Li, C. [State Key Laboratory of Oil and Gas Geology and Exploitation, Chengdu (China); Chengdu Univ. of Technology, Chengdu (China); Jiao, L.; Liu, W. [SINOPEC, Beijing (China)

    2009-07-01

    This paper discussed the procedures used to select and evaluate a surfactant for a carbon dioxide (CO{sub 2}) foam flooding project located in a heterogenous sandstone reservoir in China. Considerations for the project included the design of injection rates for the different porosity and permeability levels in the reservoir, and the sealing of large pores and high permeable zones prior to the CO{sub 2} injections in order to prevent gas breakthrough. Performance testing for the surfactant was conducted in order to assess its stability and absorbance properties. Experimental studies were conducted to determine the frothing capacity of the foam as well as to measure its volume and compatibility with formation water. Further tests were conducted to measure the pore volume and porosity of a core saturated with formation water and injected with the foam. Results of the study demonstrated that the YFP-2 foam liquid can be safely used to prevent gas breakthrough. Surfactant stability was largely influenced by temperature, salinity, and pH. 7 refs., 9 tabs., 7 figs.

  12. Artificial Neural Network Model for Alkali-Surfactant-Polymer Flooding in Viscous Oil Reservoirs: Generation and Application

    Directory of Open Access Journals (Sweden)

    Si Le Van

    2016-12-01

    Full Text Available Chemical flooding has been widely utilized to recover a large portion of the oil remaining in light and viscous oil reservoirs after the primary and secondary production processes. As core-flood tests and reservoir simulations take time to accurately estimate the recovery performances as well as analyzing the feasibility of an injection project, it is necessary to find a powerful tool to quickly predict the results with a level of acceptable accuracy. An approach involving the use of an artificial neural network to generate a representative model for estimating the alkali-surfactant-polymer flooding performance and evaluating the economic feasibility of viscous oil reservoirs from simulation is proposed in this study. A typical chemical flooding project was referenced for this numerical study. A number of simulations have been made for training on the basis of a base case from the design of 13 parameters. After training, the network scheme generated from a ratio data set of 50%-20%-30% corresponding to the number of samples used for training-validation-testing was selected for estimation with the total coefficient of determination of 0.986 and a root mean square error of 1.63%. In terms of model application, the chemical concentration and injection strategy were optimized to maximize the net present value (NPV of the project at a specific oil price from the just created ANN model. To evaluate the feasibility of the project comprehensively in terms of market variations, a range of oil prices from 30 $/bbl to 60 $/bbl referenced from a real market situation was considered in conjunction with its probability following a statistical distribution on the NPV computation. Feasibility analysis of the optimal chemical injection scheme revealed a variation of profit from 0.42 $MM to 1.0 $MM, corresponding to the changes in oil price. In particular, at the highest possible oil prices, the project can earn approximately 0.61 $MM to 0.87 $MM for a quarter

  13. Surfactant-enhanced alkaline flooding: Buffering at intermediate alkaline pH

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, J.; Wasan, D.T. (Illinois Inst. of Tech., Chicago, IL (United States))

    1993-11-01

    The alkaline flooding process involves injecting alkaline agents into the reservoir to produce more oil than is produced through conventional waterflooding. The interaction of the alkali in the flood water with the naturally occurring acids in the reservoir oil results in in-situ formation of soaps, which are partially responsible for lowering IFT and improving oil recovery. The extent to which IFT is lowered depends on the specific oil and injection water properties. Numerous investigators have attempted to clarify the relationship between system chemical composition and IFT. An experimental investigation of buffered alkaline flooding system chemistry was undertaken to determine the influence of various species present on interfacial tension (IFT) as a function of pH and ionic strength. IFT was found to go through an ultralow minimum in certain pH ranges. This synergism results from simultaneous adsorption of un-ionized and ionized acid species on the interface.

  14. 44 CFR 78.6 - Flood Mitigation Plan approval process.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Flood Mitigation Plan..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program FLOOD MITIGATION ASSISTANCE § 78.6 Flood Mitigation Plan approval process. The State POC will forward all...

  15. Impact of Surfactant Type on Adsorption Process and Oil Recovery: Implementation of New Surfactant Produced from Zizyphus Spina-Christi Extract

    National Research Council Canada - National Science Library

    Zargartalebi, Mohammad; Barati, Nasim; Pordel Shahri, Mojtaba

    2014-01-01

    Three different types of surfactants containing an anionic, a cationic and a new nonionic biosurfactant, Zizyphus Spina-Christi extract were used for the purpose of oil recovery in a core flood system...

  16. Surfactant process for promoting gas hydrate formation and application of the same

    Science.gov (United States)

    Rogers, Rudy E.; Zhong, Yu

    2002-01-01

    This invention relates to a method of storing gas using gas hydrates comprising forming gas hydrates in the presence of a water-surfactant solution that comprises water and surfactant. The addition of minor amounts of surfactant increases the gas hydrate formation rate, increases packing density of the solid hydrate mass and simplifies the formation-storage-decomposition process of gas hydrates. The minor amounts of surfactant also enhance the potential of gas hydrates for industrial storage applications.

  17. LOWER COST METHODS FOR IMPROVED OIL RECOVERY (IOR) VIA SURFACTANT FLOODING

    Energy Technology Data Exchange (ETDEWEB)

    William A. Goddard III; Yongchun Tang; Patrick Shuler; Mario Blanco; Seung Soon Jang; Shiang-Tai Lin; Prabal Maiti; Yongfu Wu; Stefan Iglauer; Xiaohang Zhang

    2004-09-01

    This report provides a summary of the work performed in this 3-year project sponsored by DOE. The overall objective of this project is to identify new, potentially more cost-effective surfactant formulations for improved oil recovery (IOR). The general approach is to use an integrated experimental and computational chemistry effort to improve our understanding of the link between surfactant structure and performance, and from this knowledge, develop improved IOR surfactant formulations. Accomplishments for the project include: (1) completion of a literature review to assemble current and new surfactant IOR ideas, (2) Development of new atomistic-level MD (molecular dynamic) modeling methodologies to calculate IFT (interfacial tension) rigorously from first principles, (3) exploration of less computationally intensive mesoscale methods to estimate IFT, Quantitative Structure Property Relationship (QSPR), and cohesive energy density (CED) calculations, (4) experiments to screen many surfactant structures for desirable low IFT and solid adsorption behavior, and (5) further experimental characterization of the more promising new candidate formulations (based on alkyl polyglycosides (APG) and alkyl propoxy sulfate surfactants). Important findings from this project include: (1) the IFT between two pure substances may be calculated quantitatively from fundamental principles using Molecular Dynamics, the same approach can provide qualitative results for ternary systems containing a surfactant, (2) low concentrations of alkyl polyglycoside surfactants have potential for IOR (Improved Oil Recovery) applications from a technical standpoint (if formulated properly with a cosurfactant, they can create a low IFT at low concentration) and also are viable economically as they are available commercially, and (3) the alkylpropoxy sulfate surfactants have promising IFT performance also, plus these surfactants can have high optimal salinity and so may be attractive for use in higher

  18. Comparison between micro-emulsion and surfactant solution flooding efficiency for enhanced oil recovery in TinFouye Oil Field

    Energy Technology Data Exchange (ETDEWEB)

    Bouabboune, M.; Benhadid, S. [Applied and Theoretical Fluid Mechanical Laboratory, Algiers (Algeria). Faculty of Physics; Hammouch, N. [Sonatrach, Hydra, Algiers (Algeria). Forage Division

    2006-07-01

    The TinFouye (TFY) reservoir is among the largest oil reservoirs discovered in Algeria. The reservoir has been extensively gas lifted for many years, but gas lift is now reaching its economic limits. Therefore, a tertiary enhancement method is needed. This report investigated the technical feasibility of applying a microemulsion flood to TFY reservoir. The purpose of the study was to optimize the concentration of surfactant, in order to obtain a lower interfacial tension between oil and microemulsion phases, and a high viscosity of the microemulsion compared to that of the oil phase. Another objective was to test the effectiveness of the obtained optimum chemical system for the displacement of residual oil saturation after waterflooding (secondary recovery). TinFouye reservoir conditions and samples were used in this study. Geomechanical equipment was used for the displacement experiments in porous media. Two optimum microemulsion compositions were determined through phase behavior studies: 4 wt per cent anionic surfactant, 2.5 wt per cent pentanol, total salinity of 0.5 g/l. Two surfactant solutions were prepared with the same anionic and alcohol concentration as those of the optimized microemulsions. This made it possible to compare the efficiency of displacing residual oil saturation. 12 refs., 5 tabs., 4 figs.

  19. 3-D hydrodynamic modelling of flood impacts on a building and indoor flooding processes

    Science.gov (United States)

    Gems, Bernhard; Mazzorana, Bruno; Hofer, Thomas; Sturm, Michael; Gabl, Roman; Aufleger, Markus

    2016-06-01

    Given the current challenges in flood risk management and vulnerability assessment of buildings exposed to flood hazards, this study presents three-dimensional numerical modelling of torrential floods and its interaction with buildings. By means of a case study application, the FLOW-3D software is applied to the lower reach of the Rio Vallarsa torrent in the village of Laives (Italy). A single-family house on the flood plain is therefore considered in detail. It is exposed to a 300-year flood hydrograph. Different building representation scenarios, including an entire impervious building envelope and the assumption of fully permeable doors, light shafts and windows, are analysed. The modelling results give insight into the flooding process of the building's interior, the impacting hydrodynamic forces on the exterior and interior walls, and further, they quantify the impact of the flooding of a building on the flow field on the surrounding flood plain. The presented study contributes to the development of a comprehensive physics-based vulnerability assessment framework. For pure water floods, this study presents the possibilities and limits of advanced numerical modelling techniques within flood risk management and, thereby, the planning of local structural protection measures.

  20. Experimental investigations on the fluid flow mechanism in porous media of enhanced oil recovery by alkli/surfactant/polymer flooding

    Institute of Scientific and Technical Information of China (English)

    WANG Jialu; SHEN Pingping; CHEN Yongzhong; ZHANG Zubo; JIA Xu; TIAN Yuling

    2005-01-01

    The fluid flow mechanism in porous media of enhanced oil recovery by Alkli/ Surfactant/ Polymer (ASP) flooding is investigated by measuring production performance, pressure distribution and saturation distribution through installing differential pressure transducers and saturation measuring probes in a physical model of vertical heterogeneous reservoir. The fluid flow variation in porous media is the main reason of enhanced oil recovery of ASP flooding. The pressure field and saturation field are nonlinearly coupled together and the interaction between them results in the fluid flow variation in the reservoir. In a vertical heterogeneous reservoir, the ASP agents initially flow in the high permeability layer, and fluid changes the flow direction toward the low and the middle permeability layers because the resistance in the high permeability layer is increased under the physical and chemical action of adsorption, retention and emulsion. ASP flooding displaces out not only the residual oil in the high permeability layer, but also the remaining oil in the low and the middle permeability layers by increasing swept volume and displacing efficiency.

  1. Numerical Simulation and Optimization of Enhanced Oil Recovery by the In Situ Generated CO2 Huff-n-Puff Process with Compound Surfactant

    Directory of Open Access Journals (Sweden)

    Yong Tang

    2016-01-01

    Full Text Available This paper presents the numerical investigation and optimization of the operating parameters of the in situ generated CO2 Huff-n-Puff method with compound surfactant on the performance of enhanced oil recovery. First, we conducted experiments of in situ generated CO2 and surfactant flooding. Next, we constructed a single-well radial 3D numerical model using a thermal recovery chemical flooding simulator to simulate the process of CO2 Huff-n-Puff. The activation energy and reaction enthalpy were calculated based on the reaction kinetics and thermodynamic models. The interpolation parameters were determined through history matching a series of surfactant core flooding results with the simulation model. The effect of compound surfactant on the Huff-n-Puff CO2 process was demonstrated via a series of sensitivity studies to quantify the effects of a number of operation parameters including the injection volume and mole concentration of the reagent, the injection rate, the well shut-in time, and the oil withdrawal rate. Based on the daily production rate during the period of Huff-n-Puff, a desirable agreement was shown between the field applications and simulated results.

  2. Mathematical evaluation of activated carbon adsorption for surfactant recovery in a soil washing process.

    Science.gov (United States)

    Ahn, Chi K; Lee, Min W; Lee, Dae S; Woo, Seung H; Park, Jong M

    2008-12-15

    The performances of various soil washing processes, including surfactant recovery by selective adsorption, were evaluated using a mathematical model for partitioning a target compound and surfactant in water/sorbent system. Phenanthrene was selected as a representative hazardous organic compound and Triton X-100 as a surfactant. Two activated carbons that differed in size (Darco 20-40 mesh and >100 mesh sizes) were used in adsorption experiments. The adsorption isotherms of the chemicals were used in model simulations for various washing scenarios. The optimal process conditions were suggested to minimize the dosage of activated carbon and surfactant and the number of washings. We estimated that the requirement of surfactant could be reduced to 33% of surfactant requirements (from 265 to 86.6g) with a reuse step using 9.1g activated carbon (>100 mesh) to achieve 90% removal of phenanthrene (initially 100mg kg-soil(-1)) with a water/soil ratio of 10.

  3. Pyrene removal from contaminated soil using electrokinetic process combined with surfactant

    Directory of Open Access Journals (Sweden)

    Seyed Enayat Hashemi

    2015-07-01

    Full Text Available Background: Pyrene is one of the stable polycyclic aromatic hydrocarbons that is considered as an important pollutants, because of extensive distribution in the environment and carcinogenic and mutagenic properties. Among the various treatment techniques, electrokinetic method is an environmental- friendly process for organic and mineral pollutants adsorbed to soil with fine pore size the same as clay and low hydraulic conductivity soils. For improving the efficiency of pyrene removal from soil, soulobilization of pyrene from soil could be used by surfactants. Materials and Methods : In this study, clay soil was selected as model because of the specific properties. Combined method using surfactant and electrokinetic was applied for pyrene removal from soil. Experiments were designed using response surface methodology (RSM, and effect of three variables includes surfactant concentration, voltage and surfactant type were evaluated for pyrene removal from contaminated soil. Results: Pyrene removal using anionic surfactants(SDS and nonionic surfactants(TX100 as a solubilizing agents has high removal efficiency. In the optimum condition with 95% confidence coefficient, utilizing mixed surfactants of sodium dodecyl sulfate and triton X-100 with the same volume, induced of 18.54 volt and 6.53 percent surfactant concentration have 94.6% pyrene removal efficiency. Conclusion:: Results of this study shows that electrokinetic process combined with surfactant as solubilizing agent could be applied as an efficient method for treating the pyrene-contaminated soils.

  4. BEHAVIOR OF SURFACTANT MIXTURE AT SOLID/LIQUID AND OIL/LIQUID INTERFACE IN CHEMICAL FLOODING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Prof. P. Somasundaran

    2002-03-01

    The aim of the project is to develop and evaluate efficient novel surfactant mixtures for enhanced oil recovery. Preliminary ultra-filtration tests suggest that two kinds of micelles may exist in binary surfactant mixtures at different concentrations. Due to the important role played in interfacial processes by micelles as determined by their structures, focus of the current work is on the delineation of the relationship between such aggregate structures and chemical compositions of the surfactants. A novel analytical centrifuge application is explored to generate information on structures of different surfactants aggregates. In this report, optical systems, typical output of the analytical ultracentrifuge results and four basic experiments are discussed. Initial sedimentation velocity investigations were conducted using nonyl phenol ethoxylated decyl ether (NP-10) to choose the best analytical protocol, calculate the partial specific volume and obtain information on sedimentation coefficient, aggregation mass of micelles. The partial specific volume was calculated to be 0.920. Four softwares: Optima{trademark} XL-A/XL-I data analysis software, DCDT+, Svedberg and SEDFIT, were compared for the analysis of sedimentation velocity experimental data. The sedimentation coefficient and aggregation number of NP-10 micelles obtained using the first three softwares at 25 C are 209, 127, and 111, respectively. The last one is closest to the result from Light Scattering. The reason for the differences in numbers obtained using the three softwares is discussed. Based on these tests, Svedberg and SEDFIT analysis are chosen for further studies. This approach using the analytical ultracentrifugation offers an unprecedented opportunity now to obtain important information on mixed micelles and their role in interfacial processes.

  5. Surfactants in aquatic and terrestrial environment: occurrence, behavior, and treatment processes.

    Science.gov (United States)

    Jardak, K; Drogui, P; Daghrir, R

    2016-02-01

    Surfactants belong to a group of chemicals that are well known for their cleaning properties. Their excessive use as ingredients in care products (e.g., shampoos, body wash) and in household cleaning products (e.g., dishwashing detergents, laundry detergents, hard-surface cleaners) has led to the discharge of highly contaminated wastewaters in aquatic and terrestrial environment. Once reached in the different environmental compartments (rivers, lakes, soils, and sediments), surfactants can undergo aerobic or anaerobic degradation. The most studied surfactants so far are linear alkylbenzene sulfonate (LAS), quaternary ammonium compounds (QACs), alkylphenol ethoxylate (APEOs), and alcohol ethoxylate (AEOs). Concentrations of surfactants in wastewaters can range between few micrograms to hundreds of milligrams in some cases, while it reaches several grams in sludge used for soil amendments in agricultural areas. Above the legislation standards, surfactants can be toxic to aquatic and terrestrial organisms which make treatment processes necessary before their discharge into the environment. Given this fact, biological and chemical processes should be considered for better surfactants removal. In this review, we investigate several issues with regard to: (1) the toxicity of surfactants in the environment, (2) their behavior in different ecological systems, (3) and the different treatment processes used in wastewater treatment plants in order to reduce the effects of surfactants on living organisms.

  6. Palm oil based surfactant products for petroleum industry

    Science.gov (United States)

    Permadi, P.; Fitria, R.; Hambali, E.

    2017-05-01

    In petroleum production process, many problems causing reduced production are found. These include limited oil recovery, wax deposit, asphaltene deposit, sludge deposit, and emulsion problem. Petroleum-based surfactant has been used to overcome these problems. Therefore, innovation to solve these problems using surfactant containing natural materials deserves to be developed. Palm oil-based surfactant is one of the potential alternatives for this. Various types of derivative products of palm oil-based surfactant have been developed by SBRC IPB to be used in handling problems including surfactant flooding, well stimulation, asphaltene dissolver, well cleaning, and wax removal found in oil and gas industry.

  7. Floods

    Science.gov (United States)

    Floods are common in the United States. Weather such as heavy rain, thunderstorms, hurricanes, or tsunamis can ... is breached, or when a dam breaks. Flash floods, which can develop quickly, often have a dangerous ...

  8. The Study of Vibration Processes in Oil Flooded Screw Compressors

    Directory of Open Access Journals (Sweden)

    I. V. Filippov

    2014-01-01

    Full Text Available Vibration processes that accompany most of machines and mechanisms are of interest to the researcher, as a source of information about the technical condition and the nature of the business processes flow. Vibration-based diagnostics of oil flooded screw compressors allows us to estimate the deviation of their operation from the main mode in accordance with changing the settings of vibration processes.The oil flooded screw compressor transition from the main mode of operation to the abnormal one is accompanied by complex gas-dynamic phenomena i.e. the initial gaps and their decays. This leads to changes in the nature of vibration processes, prompting suggestions that there is a relationship to a change of vibration parameters and mode of compressor operation.Studies were conducted by combined method using an analytical calculation of the decay parameters of the initial discontinuity and an experimental one based on the measurement of acceleration on the body of the real oil flooded screw compressor. A virtually adequate reaction of the decay parameters of the initial gap and the peak values of vibration acceleration to the change of operation mode of oil flooded screw compressor has been received. The peak value of the vibration acceleration was selected by the method of Gating being time-coinciding with the beginning discharge phase of the oil flooded screw compressor, and therefore, with the decay time of the initial discontinuity.This indicates a large degree of hypothesis likelihood on an existing initial break in oil flooded screw compressor when operating in abnormal conditions. This work contains the study results of vibration processes and their relationship to the operating mode of the oil flooded screw compressor, which distinguish it from the other works studied vibration processes in reciprocating compressors. The vibration parameters control of operating oil flooded screw compressor allows us to create an automatic capacity control

  9. Flooding and Flood Management

    Science.gov (United States)

    Brooks, K.N.; Fallon, J.D.; Lorenz, D.L.; Stark, J.R.; Menard, Jason; Easter, K.W.; Perry, Jim

    2011-01-01

    Floods result in great human disasters globally and nationally, causing an average of $4 billion of damages each year in the United States. Minnesota has its share of floods and flood damages, and the state has awarded nearly $278 million to local units of government for flood mitigation projects through its Flood Hazard Mitigation Grant Program. Since 1995, flood mitigation in the Red River Valley has exceeded $146 million. Considerable local and state funding has been provided to manage and mitigate problems of excess stormwater in urban areas, flooding of farmlands, and flood damages at road crossings. The cumulative costs involved with floods and flood mitigation in Minnesota are not known precisely, but it is safe to conclude that flood mitigation is a costly business. This chapter begins with a description of floods in Minneosta to provide examples and contrasts across the state. Background material is presented to provide a basic understanding of floods and flood processes, predication, and management and mitigation. Methods of analyzing and characterizing floods are presented because they affect how we respond to flooding and can influence relevant practices. The understanding and perceptions of floods and flooding commonly differ among those who work in flood forecasting, flood protection, or water resource mamnagement and citizens and businesses affected by floods. These differences can become magnified following a major flood, pointing to the need for better understanding of flooding as well as common language to describe flood risks and the uncertainty associated with determining such risks. Expectations of accurate and timely flood forecasts and our ability to control floods do not always match reality. Striving for clarity is important in formulating policies that can help avoid recurring flood damages and costs.

  10. Dissipative particle dynamics simulation of wettability alternation phenomena in the chemical flooding process

    Institute of Scientific and Technical Information of China (English)

    Xiaobo Li; Yuewu Liu; Jianfei Tang; Shujiao Li

    2009-01-01

    Wettability alternation phenomena is considered one of the most important enhanced oil recovery (EOR) mechanisms in the chemical flooding process and induced by the adsorption of surfactant on the rock surface. These phenomena are studied by a mesoscopic method named as dissipative particle dynamics (DPD). Both the alteration phenomena of water-wet to oil-wet and that of oil-wet to waterwet are simulated based on reasonable definition of interaction parameters between beads. The wetting hysteresis phenomenon and the process of oil-drops detachment from rock surfaces with different wettability are simulated by adding long-range external forces on the fluid particles. The simulation results show that, the oil drop is liable to spread on the oil-wetting surface and move in the form of liquid film flow, whereas it is likely to move as a whole on the waterwetting surface. There are the same phenomena occuring in wettability-alternated cases. The results also show that DPD method provides a feasible approach to the problems of seepage flow with physicochemical phenomena and can be used to study the mechanism of EOR of chemical flooding.

  11. SURFACTANT BASED ENHANCED OIL RECOVERY AND FOAM MOBILITY CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    George J. Hirasaki; Clarence A. Miller; Gary A. Pope; Richard E. Jackson

    2004-02-01

    Surfactant flooding has the potential to significantly increase recovery over that of conventional waterflooding. The availability of a large number of surfactant structures makes it possible to conduct a systematic study of the relation between surfactant structure and its efficacy for oil recovery. Also, the addition of an alkali such as sodium carbonate makes possible in situ generation of surfactant and significant reduction of surfactant adsorption. In addition to reduction of interfacial tension to ultra-low values, surfactants and alkali can be designed to alter wettability to enhance oil recovery. An alkaline surfactant process is designed to enhance spontaneous imbibition in fractured, oil-wet, carbonate formations. It is able to recover oil from dolomite core samples from which there was no oil recovery when placed in formation brine.

  12. BEHAVIOR OF SURFACTANT MIXTURES AT SOLID/LIQUID AND OIL/LIQUID INTERFACES IN CHEMICAL FLOODING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Prof. P. Somasundaran

    2002-09-30

    The aim of the project is to develop and evaluate efficient novel surfactant mixtures for enhanced oil recovery. Surfactant loss by adsorption or precipitation depends to a great extent on the type of surfactant complexes and aggregates formed. Such information as well as techniques to generate the information is lacking currently particularly for surfactant mixtures and surfactant/polymer systems. A novel analytical centrifuge application is explored during the last period to generate information on structures-performance relationship for different surfactant aggregates in solution and, in turn, at interfaces. To use analytical untracentrifuge for surfactant mixtures, information on partial specific volumes of single surfactants and their mixtures is required. Towards this purpose, surface tension and density measurements were performed to determine critical micellar concentrations (cmc), partial specific volumes of n-dodecyl-{beta}-Dmaltoside (DM), nonyl phenol ethoxylated decyl ether (NP-10) and their 1:1 mixtures at 25 C. Durchschlag's theoretical calculation method was adopted to calculate the partial specific volumes. Effects of temperature and mixing, as well as methods used for estimation on micellization and partial specific volumes were studied during the current period. Surface tension results revealed no interaction between the two surfactants in mixed micelles. Partial specific volume measurements also indicated no interaction in mixed micelles. Maximum adsorption density, area per molecule and free energy of micellization were also calculated. Partial specific volumes were estimated by two experimental methods: d{sub {rho}}/dc and V{sub {sigma}}. The difference between the results of using the two methods is within 0.5% deviation. It was found that the partial specific volume is concentration dependent and sensitive to changes in temperature. The information generated in this study will be used for the study of surfactant aggregate mass

  13. Visualization of surfactant enhanced NAPL mobilization and solubilization in a two-dimensional micromodel

    Energy Technology Data Exchange (ETDEWEB)

    ZHONG,LIRONG; MAYER,ALEX; GLASS JR.,ROBERT J.

    2000-03-08

    Surfactant-enhanced aquifer remediation is an emerging technology for aquifers contaminated with nonaqueous phase liquids (NAPLs). A two-dimensional micromodel and image capture system were applied to observe NAPL mobilization and solubilization phenomena. In each experiment, a common residual NAPL field was established, followed by a series of mobilization and solubilization experiments. Mobilization floods included pure water floods with variable flow rates and surfactant floods with variations in surfactant formulations. At relatively low capillary numbers (N{sub ca}<10{sup {minus}3}), the surfactant mobilization floods resulted in higher NAPL saturations than for the pure water flood, for similar N{sub ca}.These differences in macroscopic saturations are explained by differences in micro-scale mobilization processes. Solubilization of the residual NAPL remaining after the mobilization stage was dominated by the formation of dissolution fingers, which produced nonequilibrium NAPL solubilization. A macroemulsion phase also as observed to form spontaneously and persist during the solubilization stage of the experiments.

  14. Effect of Source, Surfactant, and Deposition Process on Electronic Properties of Nanotube Arrays

    Directory of Open Access Journals (Sweden)

    Dheeraj Jain

    2011-01-01

    Full Text Available The electronic properties of arrays of carbon nanotubes from several different sources differing in the manufacturing process used with a variety of average properties such as length, diameter, and chirality are studied. We used several common surfactants to disperse each of these nanotubes and then deposited them on Si wafers from their aqueous solutions using dielectrophoresis. Transport measurements were performed to compare and determine the effect of different surfactants, deposition processes, and synthesis processes on nanotubes synthesized using CVD, CoMoCAT, laser ablation, and HiPCO.

  15. Process, mechanism and impacts of scale formation in alkaline flooding by a variable porosity and permeability model

    Institute of Scientific and Technical Information of China (English)

    Zhen Zhang; Jiachun Li

    2016-01-01

    In spite of the role of alkali in enhancing oil recovery (EOR), the formation of precipitation during alkaline-surfactant-polymer (ASP) flooding can severely do harm to the stratum of oil reservoirs, which has been observed in situ tests of oil fields such as scale deposits found in oil stratum and at the bottom of oil wells. On the other hand, remarkable variation of stratum parameters, e.g., pore radius, porosity, and permeability due to scale formation consider-ably affects seepage flow and alkaline flooding process in return. The objective of this study is to firstly examine these mutual influential phenomena and corresponding mecha-nisms along with EOR during alkaline flooding when the effects of precipitation are no longer negligible. The chem-ical kinetic theory is applied for the specific fundamental reactions to describe the process of rock dissolution in silica-based reservoirs. The solubility product principle is used to analyze the mechanism of alkali scale formation in flooding. Then a 3D alkaline flooding coupling model accounting for the variation of porosity and permeability is established to quantitatively estimate the impact of alkali scales on reser-voir stratum. The reliability of the present model is verified in comparison with indoor experiments and field tests of the Daqing oil field. Then, the numerical simulations on a 1/4 well group in a 5-spot pattern show that the precipitation grows with alkali concentration, temperature, and injection pressure and, thus, reduces reservoir permeability and oil recovery correspondingly. As a result, the selection of alkali with a weak base is preferable in ASP flooding by tradeoff strategy.

  16. Effect of anionic surfactants on the process of Fenton degradation of methyl orange.

    Science.gov (United States)

    Yang, C W; Wang, D

    2009-01-01

    Fenton process has been shown to be very successful to remove dyes from water. However, the influence of other constituents in dyeing industry wastewater, such as Sodium Dodecyl Sulphate (SDS) surfactants, has not been investigated. In this study, the effect of SDS surfactant on the kinetics of Methyl Orange degradation undergoing Fenton process was investigated. Results show that Methyl Orange degradation rate decreased as SDS concentration increased, which was attributed to the consumption of hydroxyl radicals (OH) by surfactants and the formation of Methyl Orange-SDS complex. No evidence was found that the Methyl Orange degradation pathway was affected by the presence of SDS. The kinetics modelling indicates the reaction was the first-order reaction to Methyl Orange.

  17. Use of surfactants as plasticizers in preparing solid dispersions of poorly soluble API: selection of polymer-surfactant combinations using solubility parameters and testing the processability.

    Science.gov (United States)

    Ghebremeskel, Alazar N; Vemavarapu, Chandra; Lodaya, Mayur

    2007-01-10

    Formation of solid dispersions as a means to enhance the dissolution rate of poorly soluble Active pharmaceutical ingredients (APIs) typically employs hydrophilic polymer systems and surfactants. While the utility of the surfactant systems in solubilization is well known, the secondary effects of the same on processing and subsequent physical stability of the solid dispersions needs to be studied further. Physical blends of the poorly soluble API and hydrophilic polymers such as PVP-K30, Plasdone-S630, HPMC-E5, HPMCAS, and Eudragit L100 with mass ratio 1:1 were prepared. The surfactants tested in this study included Tween-80, Docusate sodium, Myrj-52, Pluronic-F68 and SLS. Thermal analysis of the API-polymer-surfactant blends suggested that the surfactants caused solvation/plasticization, manifesting in reduction of (i) the melting (T(m)) of API (ii) T(g) of the polymers and (iii) the combined T(g) of the solid dispersion formed from quench cooling. Explanation of these effects of surfactants is attempted based on their physical state (at the temperature of interest), HLB values and similarity of their solubility parameter values with respect to drug-polymer systems. Furthermore, extruded matrices containing different API-polymer (PVP-K30, Plasdone-S630, and HPMC-E5) mixtures prepared with and without surfactants, were produced by feeding the powder blend through a hot-melt extruder. The melt viscosity of the polymer blends was assessed by torque rheometry using a Haake Rheomix. The physicochemical properties of the extruded API-polymer-surfactant were characterized by differential scanning calorimetry, X-ray diffraction, Raman spectroscopy, and polarized microscopy. The results demonstrated that the glass transition temperature of the carrier polymers decreased as direct result of the surfactants in the extrudate, due to an increase in the chain mobility of polymers. A decrease in the melt viscosity was seen due to a plasticization of the polymer. The drug release

  18. Effect of bio-surfactant on municipal solid waste composting process

    Institute of Scientific and Technical Information of China (English)

    XI Bei-dou; LIU Hong-liang; HUANG G H; ZHANG Bai-yu; QIN Xiao-sheng

    2005-01-01

    Bio-surfactant is a new type of surfactant that is produced in microbial metabolism. Adding bio-surfactant during composting process, especially to those contain some toxic substances, has been proved to be a promising way. In this study, Strains Ⅲ (2), a bacterial with high activity to produce bio-surfactant, were isolated firstly. Following comparison experiments with and without adding Strains Ⅲ (2), namely Run 1 and Run R, were conducted, respectively. The experimental results showed that, by adding Strains Ⅲ (2),the surface tension could reduce from 46.5 mN/m to 39.8 mN/m and the corresponding time to maintain the surface tension under 50 mN/m could prolong from 60 h to 90 h. The oxygen uptake rate and total accumulated oxygen consumption with Stains Ⅲ (2) were both higher than those without Strains Ⅲ (2), while the accumulation of H2S in outlet gas was reduced to around 50% of Run R. Moreover, two additional experiments were also carried out to examine the effects of strains coming from different systems. One is adding Strains Ⅲ (2)with a dose of 0.4% (Run 2), and the other is seedling commercial Strains at the same conditions, the composting experiments showed that: Run 2 was more effective than Run 3, because the commercial Strains can be suppressed significantly in a complex composting system with different pH, high temperature and some of metals. The bio-surfactant was also added into the solid waste, which contained some toxic substances, the corresponding results showed that the remove rate of Hg and sodium pentachlorophenolate(PCP-Na) could be improved highly. Thus, the microenvironment, reactionrate and composting quality could be enhanced effectively by adding bio-surfactant to the composting process.

  19. Physical Simulation Experiment Research on Surfactant/Polymer Flooding in Shuang He Oil Field%双河油田S/P二元复合驱物理模拟实验研究

    Institute of Scientific and Technical Information of China (English)

    倪洪涛

    2011-01-01

    438 zoneⅠⅡ1-2 layer system of Shuanghe oilfield has entered ultra-high water cut stage.In order to assurance the file result of surfactant/polyment flooding,this paper studies the physical simulation flooding test. Based on this,injection parameters of the surfactant/polyment flooding is suits to research block: optium concentration of surfactant is 0.3% and plug is 0.4PV.Influence factors were analyzed to surfactant/polyment flooding.This research provide theoretical foundation to improve oil recovery in field test of Shuanghe.%双河油田438块ⅠⅡ1-2层系目前已进入水驱开发特高含水阶段,为保证二元复合驱矿场应用效果,本文通过开展非均质仿真模型二元复合驱实验,给出适用于研究区块二元复合驱注入参数的技术界限:表面活性剂最佳浓度为0.3%,段塞大小为0.4PV;并对二元复合驱影响因素进行分析,为双河二元驱提高采收率现场试验提供理论基础。

  20. Enhancing flood forecasting with the help of processed based calibration

    Science.gov (United States)

    Cullmann, Johannes; Krauße, Thomas; Philipp, Andy

    Due to the fact that the required input data are not always completely available and model structures are only a crude description of the underlying natural processes, model parameters need to be calibrated. Calibrated model parameters only reflect a small domain of the natural processes well. This imposes an obstacle on the accuracy of modelling a wide range of flood events, which, in turn is crucial for flood forecasting systems. Together with the rigid model structures of currently available rainfall-runoff models this presents a serious constraint to portraying the highly non-linear transformation of precipitation into runoff. Different model concepts (interflow, direct runoff), or rather the represented processes, such as infiltration, soil water movement etc. are more or less dominating different sections of the runoff spectrum. Most models do not account for such transient characteristics inherent to the hydrograph. In this paper we try to show a way out of the dilemma of limited model parameter validity. Exemplarily, we investigate on the model performance of WaSiM-ETH, focusing on the parameterisation strategy in the context of flood forecasting. In order to compensate for the non-transient parameters of the WaSiM model we propose a process based parameterisation strategy. This starts from a detailed analysis of the considered catchments rainfall-runoff characteristics. Based on a classification of events, WaSiM-ETH is calibrated and validated to describe all the event classes separately. These specific WaSiM-ETH event class models are then merged to improve the model performance in predicting peak flows. This improved catchment modelling can be used to train an artificial intelligence based black box forecasting tool as described in [Schmitz, G.H., Cullmann, J., Görner, W., Lennartz, F., Dröge, W., 2005. PAI-OFF: Eine neue Strategie zur Hochwasservorhersage in schnellreagierenden Einzugsgebieten. Hydrologie und Wasserbewirtschaftung 49, 226

  1. Degradation of the commercial surfactant nonylphenol ethoxylate by advanced oxidation processes.

    Science.gov (United States)

    da Silva, Salatiel Wohlmuth; Klauck, Cláudia Regina; Siqueira, Marco Antônio; Bernardes, Andréa Moura

    2015-01-23

    Four different oxidation process, namely direct photolysis (DP) and three advanced oxidation processes (heterogeneous photocatalysis - HP, eletrochemical oxidation - EO and photo-assisted electrochemical oxidation - PEO) were applied in the treatment of wastewater containing nonylphenol ethoxylate (NPnEO). The objective of this work was to determine which treatment would be the best option in terms of degradation of NPnEO without the subsequent generation of toxic compounds. In order to investigate the degradation of the surfactant, the processes were compared in terms of UV/Vis spectrum, mineralization (total organic carbon), reaction kinetics, energy efficiency and phytotoxicity. A solution containing NPnEO was prepared as a surrogate of the degreasing wastewater, was used in the processes. The results showed that the photo-assisted processes degrade the surfactant, producing biodegradable intermediates in the reaction. On the other hand, the electrochemical process influences the mineralization of the surfactant. The process of PEO carried out with a 250W lamp and a current density of 10mA/cm(2) showed the best results in terms of degradation, mineralization, reaction kinetics and energy consumption, in addition to not presenting phytotoxicity. Based on this information, this process can be a viable alternative for treating wastewater containing NPnEO, avoiding the contamination of water resources. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Development of improved mobility control agents for surfactant/polymer flooding. Second annual report, October 1, 1979-September 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Martin, F.D.; Donaruma, L.G.; Hatch, M.J.

    1981-04-01

    The objective of this laboratory work is to develop improved mobility control agents that are more effective than the commercial polymers currently used in this process. During the second year of the project, the baseline testing of commercial products was completed. These baseline tests with polymers include studies on mobility control, retention, and shear degradation in Berea cores, the effect of common ions on rheological properties, thermal stability, microbial degradation, and surfactant-polymer interactions. These data are used for comparison of the commercial agents at standardized sets of conditions, and are also used to evaluate new, modified, or improved polymers. Work was also initiated on the synthesis, characterization, and preliminary screening of new and modified polymers. Testing of these analogs provides systematic correlations of polymer performance with polymer structure. This preliminary testing consists of measurements of shear degradation and viscosity loss in NaCl brines by the use of a simplified screening procedure. To date, a number of potential structure-utility relationships have been observed. Solution viscosities of all nonionic polymers tested are essentially insensitive to changes in NaCl concentration. Increasing the charge-to-mass ratio (degree of hydrolysis) of either polyacrylamides or N-alkyl analogs enhances the ability of these polymers to build viscosity in low salinity NaCl brines. However, such polymers are increasingly subject to viscosity loss as the salinity is increased. Above a certain critical molecular weight, polymers become more susceptible to shear degradation. Many of the polymers that possess stiffer backbones exhibit improved brine and shear stability. The results of these studies will be used to develop an improved mobility control polymer in the next phase of this project.

  3. Biobased surfactant-like molecules from organic wastes: the effect of waste composition and composting process on surfactant properties and on the ability to solubilize Tetrachloroethene (PCE).

    Science.gov (United States)

    Quadri, Giorgia; Chen, Xiaosong; Jawitz, James W; Tambone, Fulvia; Genevini, Pierluigi; Faoro, Franco; Adani, Fabrizio

    2008-04-01

    In this work, four surfactant-like humic acids (HAs) obtained from garden lignocellulose wastes and kitchen food wastes mixed with garden-lignocellulose wastes, both before and after composting, were tested for surfactant properties and the ability to solubilize tetrachloroethene (PCE). The waste-derived HAs showed good surfactant properties, lowering the water surface tension from 74 mN m(-1) to 45.4 +/- 4.4 mN m(-1), with a critical micelle concentration (CMC) of 1.54 +/- 1.68 g L(-1), which is lower than many synthetic ionic surfactants. CMC was affected by both waste origin and composting processes. The addition of food waste and composting reduced CMC by adding alkyl-C (measured by CP MAS 13C NMR) and N- and S-HA contents (amide molecules), so that a multistep regression was found [CMC = 24.6 - 0.189 alkyl C - 2.64 (N + S); R2 = 0.77, P < 0.10, n = 6]. The four HAs solubilized PCE at the rate of 0.18-0.47 g PCE/g aqueous biosurfactant. These results were much higher than those reported in the literature for a commercial HA (0.026 g/g), but they were in line with those measured in this work for nonionic surfactants such as Tween-80 (0.69 g/g) and Triton X-100 (1.08 g/g).

  4. Surfactant Based Enhanced Oil Recovery and Foam Mobility Control

    Energy Technology Data Exchange (ETDEWEB)

    George J. Hirasaki; Clarence A. Miller

    2006-09-09

    Surfactant flooding has the potential to significantly increase recovery over that of conventional waterflooding. The availability of a large number of surfactant structures makes it possible to conduct a systematic study of the relation between surfactant structure and its efficacy for oil recovery. A mixture of two surfactants was found to be particularly effective for application in carbonate formations at low temperature. The mixture is single phase for higher salinity or calcium concentrations than that for either surfactant used alone. This makes it possible to inject the surfactant slug with polymer close to optimal conditions and yet be single phase. A formulation has been designed for a particular field application. It uses partially hydrolyzed polyacrylamide for mobility control. The addition of an alkali such as sodium carbonate makes possible in situ generation of naphthenic soap and significant reduction of synthetic surfactant adsorption. The design of the process to maximize the region of ultra-low IFT takes advantage of the observation that the ratio of soap to synthetic surfactant is a parameter in the conditions for optimal salinity. Even for a fixed ratio of soap to surfactant, the range of salinity for low IFT was wider than that reported for surfactant systems in the literature. Low temperature, forced displacement experiments in dolomite and silica sandpacks demonstrate that greater than 95% recovery of the waterflood remaining oil is possible with 0.2% surfactant concentration, 0.5 PV surfactant slug, with no alcohol. Compositional simulation of the displacement process demonstrates the role of soap/surfactant ratio on passage of the profile through the ultralow IFT region, the importance of a wide salinity range of low IFT, and the importance of the viscosity of the surfactant slug. Mobility control is essential for surfactant EOR. Foam is evaluated to improve the sweep efficiency of surfactant injected into fractured reservoirs as well as a

  5. Atmospheric processes triggering the central European floods in June 2013

    Directory of Open Access Journals (Sweden)

    C. M. Grams

    2014-07-01

    Full Text Available In June 2013, central Europe was hit by a century flood affecting the Danube and Elbe catchments after a 4 day period of heavy precipitation and causing severe human and economic loss. In this study model analysis and observational data are investigated to reveal the key atmospheric processes that caused the heavy precipitation event. The period preceding the flood was characterised by a weather regime associated with cool and unusual wet conditions resulting from repeated Rossby wave breaking (RWB. During the event a single RWB established a reversed baroclinicity in the low to mid-troposphere in central Europe with cool air trapped over the Alps and warmer air to the north. The upper-level cut-off resulting from the RWB instigated three consecutive cyclones in eastern Europe that unusually tracked westward during the days of heavy precipitation. Continuous large-scale slantwise ascent in so-called "equatorward ascending" warm conveyor belts (WCBs associated with these cyclones is found as the key process that caused the 4 day heavy precipitation period. Fed by moisture sources from continental evapotranspiration, these WCBs unusually ascended equatorward along the southward sloping moist isentropes. Although "equatorward ascending" WCBs are climatologically rare events, they have great potential for causing high impact weather.

  6. SURFACTANT BASED ENHANCED OIL RECOVERY AND FOAM MOBILITY CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    George J. Hirasaki; Clarence A. Miller; Gary A. Pope; Richard E. Jackson

    2004-07-01

    Surfactant flooding has the potential to significantly increase recovery over that of conventional waterflooding. The availability of a large number of surfactants makes it possible to conduct a systematic study of the relation between surfactant structure and its efficacy for oil recovery. Also, the addition of an alkali such as sodium carbonate makes possible in situ generation of surfactant and significant reduction of surfactant adsorption. In addition to reduction of interfacial tension to ultra-low values, surfactants and alkali can be designed to alter wettability to enhance oil recovery. An alkaline surfactant process is designed to enhance spontaneous imbibition in fractured, oil-wet, carbonate formations. It is able to recover oil from dolomite core samples from which there was no oil recovery when placed in formation brine. Mobility control is essential for surfactant EOR. Foam is evaluted to improve the sweep efficiency of surfactant injected into fractured reservoirs. UTCHEM is a reservoir simulator specially designed for surfactant EOR. A dual-porosity version is demonstrated as a potential scale-up tool for fractured reservoirs.

  7. Effect of Surfactant Concentration in the Emulsions on the Process of Oleophilic Porous Structures Imbibition

    Directory of Open Access Journals (Sweden)

    Shtyka Olga S.

    2016-01-01

    Full Text Available The spontaneous imbibition has been a subject of the scientific interest being a background process for numerous industrial technologies and occurring in the natural environment. In literature the experimental and theoretical results regarding this phenomenon describe a media imbibition with single-phase liquids and the relation between the process rate and media characteristics. The imbibition of oleophilic porous structures with two-phase liquids, only one phase of which was wetting, is an objective of the current publication. The main purpose is to estimate the influence of both surfactant fraction and the dispersed phase concentration on the mentioned process. The imbibition rate was investigated during model experiments with stabilized oil-in-water emulsions having the dispersed phase concentrations of 10 vol%, 30 vol% and 50 vol%. The prepared emulsions differed with fraction of the added surfactant, i.e. 1 vol%, 2 vol% and 5 vol%. The obtained results allowed to conclude that at the him≥0.02 m, the dispersed phase concentration and viscosity decreased versus height. However, the raise of the surfactant fraction caused the increase of mass and height of the imbibed emulsions in porous medium. Moreover, this provided increasing of viscosity and a change of emulsions behaviour as a liquid.

  8. Degradation of the commercial surfactant nonylphenol ethoxylate by advanced oxidation processes

    Energy Technology Data Exchange (ETDEWEB)

    Wohlmuth da Silva, Salatiel, E-mail: salatielws@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS) – Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais (PPGEM), Av. Bento Gonçalves, 9500, Porto Alegre, RS (Brazil); Klauck, Cláudia Regina, E-mail: claudiark@feevale.br [Universidade Feevale, Campus II ERS-239, 2755, Novo Hamburgo, RS (Brazil); Siqueira, Marco Antônio, E-mail: marcor@feevale.br [Universidade Feevale, Campus II ERS-239, 2755, Novo Hamburgo, RS (Brazil); Bernardes, Andréa Moura, E-mail: amb@ufrgs.br [Universidade Federal do Rio Grande do Sul (UFRGS) – Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais (PPGEM), Av. Bento Gonçalves, 9500, Porto Alegre, RS (Brazil)

    2015-01-23

    Highlights: • NP{sub 4}EO in industrial effluents can be treated before reaching water reservoirs. • Advanced oxidation processes are proposed for the degradation of NP{sub 4}EO. • The degradation rate depends mainly on the light intensity. • The mineralization rate depends mainly on the current density. • Photo-assisted electrochemical oxidation showed the best degradation results. - Abstract: Four different oxidation process, namely direct photolysis (DP) and three advanced oxidation processes (heterogeneous photocatalysis – HP, eletrochemical oxidation – EO and photo-assisted electrochemical oxidation – PEO) were applied in the treatment of wastewater containing nonylphenol ethoxylate (NP{sub n}EO). The objective of this work was to determine which treatment would be the best option in terms of degradation of NP{sub n}EO without the subsequent generation of toxic compounds. In order to investigate the degradation of the surfactant, the processes were compared in terms of UV/Vis spectrum, mineralization (total organic carbon), reaction kinetics, energy efficiency and phytotoxicity. A solution containing NP{sub n}EO was prepared as a surrogate of the degreasing wastewater, was used in the processes. The results showed that the photo-assisted processes degrade the surfactant, producing biodegradable intermediates in the reaction. On the other hand, the electrochemical process influences the mineralization of the surfactant. The process of PEO carried out with a 250 W lamp and a current density of 10 mA/cm{sup 2} showed the best results in terms of degradation, mineralization, reaction kinetics and energy consumption, in addition to not presenting phytotoxicity. Based on this information, this process can be a viable alternative for treating wastewater containing NP{sub n}EO, avoiding the contamination of water resources.

  9. Surfactant Based Enhanced Oil Recovery and Foam Mobility Control

    Energy Technology Data Exchange (ETDEWEB)

    George J. Hirasaki; Clarence A. Miller; Gary A. Pope

    2005-07-01

    Surfactant flooding has the potential to significantly increase recovery over that of conventional waterflooding. The availability of a large number of surfactant structures makes it possible to conduct a systematic study of the relation between surfactant structure and its efficacy for oil recovery. A combination of two surfactants was found to be particularly effective for application in carbonate formations at low temperature. A formulation has been designed for a particular field application. The addition of an alkali such as sodium carbonate makes possible in situ generation of surfactant and significant reduction of surfactant adsorption. In addition to reduction of interfacial tension to ultra-low values, surfactants and alkali can be designed to alter wettability to enhance oil recovery. The design of the process to maximize the region of ultra-low IFT is more challenging since the ratio of soap to synthetic surfactant is a parameter in the conditions for optimal salinity. Compositional simulation of the displacement process demonstrates the interdependence of the various components for oil recovery. An alkaline surfactant process is designed to enhance spontaneous imbibition in fractured, oil-wet, carbonate formations. It is able to recover oil from dolomite core samples from which there was no oil recovery when placed in formation brine. Mobility control is essential for surfactant EOR. Foam is evaluated to improve the sweep efficiency of surfactant injected into fractured reservoirs. UTCHEM is a reservoir simulator specially designed for surfactant EOR. It has been modified to represent the effects of a change in wettability. Simulated case studies demonstrate the effects of wettability.

  10. Surfactants as additives for NO{sub x} reduction during SNCR process with urea solution as reducing agent

    Energy Technology Data Exchange (ETDEWEB)

    Ayoub, Muhammad [Department of Environmental Engineering, Kwangwoon University (Korea, Republic of); Irfan, Muhammad Faisal, E-mail: muhammadfipk@um.edu.my [Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Yoo, Kyung-Seun [Department of Environmental Engineering, Kwangwoon University (Korea, Republic of)

    2011-09-15

    Highlights: {yields} We study SNCR process using urea as a reducing agent for NO{sub x} reduction. {yields} We improve NO{sub x} reduction efficiency by adding the different types of additives. {yields} We introduce new additives: surfactants and blends of alkali metal with organic group. {yields} Anionic surfactants give maximum efficiency and max. range for temperature window. - Abstract: NO{sub x} reduction from gas stream by selective non-catalytic reduction (SNCR) using urea as a reducing agent was performed in this study. A Pilot-scale experimental system was designed and constructed to evaluate the NO{sub x} reduction efficiency and temperature window of the process. Particularly, different types of additives were added during SNCR process to improve NO{sub x} reduction efficiency and enlarge temperature window. The addition of additives was based on organic compounds like alcoholic group (CH{sub 3}OH, C{sub 2}H{sub 5}OH and C{sub 3}H{sub 7}OH) and metallic compounds like alkali metals (NaOH, KOH and LiOH). Some newly introduced additives, such as surfactants and different blends of alkali metal NaOH (1%) with organic group or surfactants were also added to assess the effect of these mixed additives on NO{sub x} reduction efficiency and reaction temperature window during SNCR process. Main focus was laid on surfactants as an additive because of their cost effectiveness and availability. Basically, surfactants have both organic and metallic parts which provide -OH free radicals from both ends (organic and metallic) to enhance the reaction mechanism and improve the NO{sub x} reduction at low temperature. Different types of surfactants (anionic, cationic, amphitricha, long chain, short chain and with different functional groups attached to chains) were tested as an additive during SNCR process. Anionic surfactants (SPES, APS, LAS and SPS) gave maximum efficiency for NO{sub x} reduction and provided maximum range for the temperature window.

  11. Wuliwan surfactant combination adjustable flooding technology research and test%五里湾长6油藏聚表二元驱研究与应用

    Institute of Scientific and Technical Information of China (English)

    徐艳丽; 龙永福; 王涛; 刘秀华; 高挺; 王伟华

    2012-01-01

    Wuliwan is a typical low porosity and low permeability reservoir,with the exten- sion of oilfield development time, Oil well water rising velocity continues to accelerate, Wa- terflood efficiency decrease, the steady production of oil field is difficult.In order to delay the water rising velocity,Improve the ultimate recovery,To carry out the polymer and surfactant combined flooding technology research.Through the technology of profile control and oil dis- placement technology combined with the use of,From improving the swept volume,and in- creasing the oil displacement efficiency to Increasing oil production.The technology through the indoor experiment, And selected three wells of Wuliwan to carry out the test, The experi- mental results provide reference,as the polymer and surfactant combined flooding technique in low permeability reservoir.%五里湾是典型的低孔低渗油藏,并随着该油田开发时间的延长,油井含水上升速度不断加快,水驱油效率降低,油田稳产难度加大。为了有效延缓含水上升速度,提高油井最终采收率,开展了聚合物与表面活性剂组合调驱技术研究。拟通过调剖技术和驱油技术结合运用,从提高波及体积、增加洗油效率两方面综合增油。该技术通过全面的室内实验,并选取五里湾一区三口水井开展该项试验,试验结果为聚合物与表面活性剂组合调驱技术在低渗透油藏的运用提供试验参考。

  12. Theoretical investigation of process controls upon flood frequency: role of thresholds

    Directory of Open Access Journals (Sweden)

    I. Struthers

    2006-10-01

    Full Text Available Traditional statistical approaches to flood frequency inherently assume homogeneity and stationarity in the flood generation process. This study illustrates the impact of heterogeneity associated with threshold non-linearities in the storage-discharge relationship associated with the rainfall-runoff process upon flood frequency behaviour. For a simplified, non-threshold (i.e. homogeneous scenario, flood frequency can be characterised in terms of rainfall frequency, the characteristic response time of the catchment, and storm intermittency, modified by the relative strength of evaporation. The flood frequency curve is then a consistent transformation of the rainfall frequency curve, and could be readily described by traditional statistical methods. The introduction of storage thresholds, namely a field capacity storage and a catchment storage capacity, however, results in different flood frequency "regions" associated with distinctly different rainfall-runoff response behaviour and different process controls. The return period associated with the transition between these regions is directly related to the frequency of threshold exceedence. Where threshold exceedence is relatively rare, statistical extrapolation of flood frequency on the basis of short historical flood records risks ignoring this heterogeneity, and therefore significantly underestimating the magnitude of extreme flood peaks.

  13. A process flood typology along an Alpine transect: analysis based on observations and modelling approaches

    Science.gov (United States)

    Zoccatelli, Davide; Parajka, Juraj; Gaál, Ladislav; Blöschl, Günter; Borga, Marco

    2014-05-01

    Understanding the effects of climate changes on river floods requires a better understanding of the control of climate variability on flood regimes. The aim of this work is to identify the process types of causative mechanisms of floods along a longitudinal Alpine transect spanning 200 km from Verona in Italy to lower Germany. The investigation is focused on the analysis of the statistical properties of the various flood typologies, their spatial organization and their relation with the topography of the transect. Along the transect, 34 basins were selected following criteria of basin size (between 50 and 500 km2), amount of hydrometeorological data available and impact of hydraulic structures on runoff regime. Around 20 years of hourly data of discharge, precipitation and temperature were collected for each basin. The three most intense floods occurred each year are considered in the work. Precipitation and temperature follow a sharp gradient across the transect, with both precipitation and temperature low around the main alpine ridge. Four flood types are considered: long-rain floods, flash floods, rain-on-snow floods, and snowmelt floods. For the classification we use a combination of a number of process indicators, including the timing of the floods, storm duration, rainfall depths, snowmelt contribution to runoff, initial catchment state and runoff response dynamics, using a procedure similar to what described in Merz and Blöschl (2003). The indicators for flood classification are derived based on either observed discharge data and model results. Comparison between the two derived flood classifications allows one to analyse the viability of using a model approach to build flood typologies in basins characterized by varying data availability. Finally, a sensitivity analysis is carried out by imposing step changes to the precipitation and temperature pattern. The resulting distribution of flood types gives an insight on the possible change in floods

  14. 克拉玛依油田二元复合驱的配制%Preparation of surfactant-polymer flooding in Kelamayi oil field

    Institute of Scientific and Technical Information of China (English)

    李龙; 黄强; 梁金强; 唐治国; 高丽

    2013-01-01

    Poly-surfactant composite flooding is a new enhanced oil recovery (EOR) technology in the oil field, which has a great significance to enhance oil recovery for the old oil filed. Based on the ground flooding way of ASP, the geological characteristics of even central areas of Kalamay Oil Field and the formulation requirement of SP, the purified produced water from production of crude oil is used as dissolved fluid of SP to ensure the compatibility and reliability for the ground system of SP. It can fully use the heat energy and guarantee the accuracy of the concentration of SP. At the same time,it can greatly reduce the shear property of the polymer and ensure the viscosity requirement of SP, thus greatly enhance the economic benefits of EOR.%二元复合驱技术作为油田三次采油全新的采油方式对提高老油田采收率具有极为重要的意义.在对三元复合驱地面注入方式研究的基础上,为保证二元复合驱地面系统的适应性和可靠性,针对克拉玛依油田七中区二元复合驱地质特点和配方要求,二元复合驱采用净化后的原油采出水作为溶解液,充分利用热能,保证了二元复合驱浓度的准确性,最大程度降低了对聚合物的剪切,保证了二元复合驱的黏度,提高了油田三次采油的经济效益.

  15. Process-based distributed hydrological modelling of annual floods in the Upper Zambezi using the Desert Flood Index

    Science.gov (United States)

    Meinhardt, Markus; Sven, Kralisch; Manfred, Fink; Daniel, Butchart-Kuhlmann; Anthony, Chabala; Melanie, Fleischer; Jörg, Helmschrot; Wilson, Phiri; Tina, Trautmann; Henry, Zimba; Imasiku, Nyambe

    2016-04-01

    Wetland areas are especially sensitive to changes in hydrological conditions. The catchment of the Luanginga River, a tributary of the Upper Zambezi which covers about 33000 km², shows this characteristic in an exemplary way. Ranging from the Angolan highlands to the Barotse floodplain of the Zambezi River , it is characterized by an annual flow regime and extensive wetland areas. Due to its annual flooding with peak times in April, the area features exceptionally fertile soils with high agricultural production and is further known for its rich cultural heritage, making it especially sensitive to changes of hydrological conditions . To identify possible changes related to projected climate and land management change, especially in the area of the floodplain, there is a need to apply a process-based distributed hydrological model of the annual floods . Remote sensing techniques have shown to be appropriate to identify the extend of the important flooding and were used to validate the model in space and time. The results of this research can be used as a basis with which to provide evidence-based advice and information for all decision-makers and stakeholders in the region. For this assessment , such a modelling approach is applied to adequately represent hydrological processes and to address key water resources management issues at sub-basin levels. Introducing a wetland simulation extension, the model allows to represent the annual flood regime of the system and thus to address the effect of climate change and upstream land use changes on flow regimes in the downstream watershed. In order to provide a basis for model validation and calibration, the inundated area was determined using the Desert Flood Index (DFI), which was generated from a time series of Landsat images. We will give a short introduction to the study area and related water resources management problems, present the intended model structure and show first simulations and model validation results

  16. Comparative hazard analysis of processes leading to remarkable flash floods (France, 1930-1999)

    Science.gov (United States)

    Boudou, M.; Lang, M.; Vinet, F.; Cœur, D.

    2016-10-01

    Flash flood events are responsible for large economic losses and lead to fatalities every year in France. This is especially the case in the Mediterranean and oversea territories/departments of France, characterized by extreme hydro-climatological features and with a large part of the population exposed to flood risks. The recurrence of remarkable flash flood events, associated with high hazard intensity, significant damage and socio-political consequences, therefore raises several issues for authorities and risk management policies. This study aims to improve our understanding of the hazard analysis process in the case of four remarkable flood events: March 1930, October 1940, January 1980 and November 1999. Firstly, we present the methodology used to define the remarkability score of a flood event. Then, to identify the factors leading to a remarkable flood event, we explore the main parameters of the hazard analysis process, such as the meteorological triggering conditions, the return period of the rainfall and peak discharge, as well as some additional factors (initial catchment state, flood chronology, cascade effects, etc.). The results contribute to understanding the complexity of the processes leading to flood hazard and highlight the importance for risk managers of taking additional factors into account.

  17. Effect of nonionic surfactant addition on Pyrex glass ablation using water-assisted CO2 laser processing

    Science.gov (United States)

    Chung, C. K.; Liao, M. W.; Lin, S. L.

    2010-04-01

    Pyrex glass etching using laser ablation is an important technology for the microfluid application to lab-on-a-chip devices but suffers from the formation of surface crack. In this article, the addition of nonionic surfactant to water for glass ablation using water-assisted CO2 laser processing (WACLAP) has been investigated to enhance ablation rate and to eliminate conventional surface defects of cracks in air. WACLAP for Pyrex glass ablation can reduce thermal-stress-induced crack with water cooling and hydrophilic nonionic surfactant to water can enhance ablation performance. Compared to pure water, the 15% weight percent Lauramidopropyl Betaine surfactant solutions for WACLAP can enhance ablation rate from 13.6 to 25 μm/pass of Pyrex glass ablation at a linear laser energy density of 2.11 J/cm, i.e., 24 W power, 114 mm/s scanning speed, and obtain through-wafer etching at 3.16 J/cm for 20 passes without cracks on the surface. Effect of surfactant concentration and linear energy density on WACLAP was also examined. The possible mechanism of surfactant-enhanced phenomenon was discussed by the Newton’s law of viscosity of surfactant solution.

  18. Significantly Enhanced Actuation Performance of IPMC by Surfactant-Assisted Processable MWCNT/Nafion Composite

    Institute of Scientific and Technical Information of China (English)

    Qingsong He; Min Yu; Dingshan Yu; Yan Ding; Zhendong Dai

    2013-01-01

    The performance of Ionic Polymer Metal Composite (IPMC) actuator was significantly enhanced by incorporating surfactant-assisted processable Multi-Walled Carbon Nanotubes (MWCNTs) into a Nation solution.Cationic surfactant Cetyl Trimethyl Ammonium Bromide (CTAB) was employed to disperse MWCNTs in the Nation matrix,forming a homogeneous and stable dispersion of nanotubes.The processing did not involve any strong acid treatment and thus effectively preserved the excellent electronic properties associated with MWCNT.The as-obtained MWCNT/Nafion-IPMC actuator was tested in terms of conductivity,bulk and surface morphology,blocking force and electric current.It was shown that the blocking force and the current of the new IPMC are 2.4 times and 1.67 times higher compared with a pure Nation-based IPMC.Moreover,the MWCNT/IPMC performance is much better than previously reported Nafion-IPMC doped by acid-treated MWCNT.Such significantly improved performance should be attributed to the improvement of electrical property associated with the addition of MWCNTs without acid treatment.

  19. Reservoir Characterization of Bridgeport and Cypress Sandstones in Lawrence Field Illinois to Improve Petroleum Recovery by Alkaline-Surfactant-Polymer Flood

    Energy Technology Data Exchange (ETDEWEB)

    Seyler, Beverly; Grube, John; Huff, Bryan; Webb, Nathan; Damico, James; Blakley, Curt; Madhavan, Vineeth; Johanek, Philip; Frailey, Scott

    2012-12-21

    Within the Illinois Basin, most of the oilfields are mature and have been extensively waterflooded with water cuts that range up to 99% in many of the larger fields. In order to maximize production of significant remaining mobile oil from these fields, new recovery techniques need to be researched and applied. The purpose of this project was to conduct reservoir characterization studies supporting Alkaline-Surfactant-Polymer Floods in two distinct sandstone reservoirs in Lawrence Field, Lawrence County, Illinois. A project using alkaline-surfactantpolymer (ASP) has been established in the century old Lawrence Field in southeastern Illinois where original oil in place (OOIP) is estimated at over a billion barrels and 400 million barrels have been recovered leaving more than 600 million barrels as an EOR target. Radial core flood analysis using core from the field demonstrated recoveries greater than 20% of OOIP. While the lab results are likely optimistic to actual field performance, the ASP tests indicate that substantial reserves could be recovered even if the field results are 5 to 10% of OOIP. Reservoir characterization is a key factor in the success of any EOR application. Reservoirs within the Illinois Basin are frequently characterized as being highly compartmentalized resulting in multiple flow unit configurations. The research conducted on Lawrence Field focused on characteristics that define reservoir compartmentalization in order to delineate preferred target areas so that the chemical flood can be designed and implemented for the greatest recovery potential. Along with traditional facies mapping, core analyses and petrographic analyses, conceptual geological models were constructed and used to develop 3D geocellular models, a valuable tool for visualizing reservoir architecture and also a prerequisite for reservoir simulation modeling. Cores were described and potential permeability barriers were correlated using geophysical logs. Petrographic analyses

  20. The resilience of neighborhood social processes: A case study of the 2011 Brisbane flood.

    Science.gov (United States)

    Wickes, Rebecca; Britt, Chester; Broidy, Lisa

    2017-02-01

    Social disorganization theories position neighborhood social capital and collective efficacy as key social processes that should facilitate community resilience in the aftermath of disaster. Yet limited evidence demonstrates that these social processes are themselves resilient with some studies showing that disaster can fracture even once cohesive neighborhoods. In this paper we assess the stability of neighborhood level collective efficacy and social capital before and after a disaster. We use multilevel structural equation modeling and draw on census and longitudinal survey data collected from over 4000 residents living in 148 neighborhoods in Brisbane, Australia before and after a significant flood event. We examine what happens to social capital and collective efficacy in flooded and non-flooded neighborhoods and assess whether demographic shifts are associated with change and/or stability in these processes. We find strong evidence that these processes operate similarly across flooded and not flooded communities. Our findings also reveal significant stability for our measures of social capital across time, while collective efficacy increases post flood across all neighborhoods, but more so in flooded neighborhoods. Neighborhood demographics have limited effect on patterns of stability or change in these social processes. We discuss the theoretical and practical implications of these findings for our understanding of neighborhood resilience in the wake of disaster.

  1. Investigating the role of polymer type and dead end pores’ distribution on oil recovery efficiency during ASP flooding

    OpenAIRE

    Mohammad Hossein Sedaghat; Amir Hatampour; Rasool Razmi

    2013-01-01

    Although alkaline-surfactant-polymer flooding is proved to be efficient for oil recovery from petroleum reservoirs, effects of existence of dead end pores on this process need more discussions. In this work, several ASP flooding tests constituted from 4 polymers, 1 surfactant and 1 alkaline were performed on micromodels designed in four various dead end pore distributions initially saturated with crude oil. The results showed that although using ASP solution constituted from hydrolyzed polyme...

  2. Effects of connate water on chemical flooding processes in porous media

    Energy Technology Data Exchange (ETDEWEB)

    Thibodeau, L.; Neale, G.H. [Department of Chemical Engineering, University of Ottawa, Ottawa, ON (Canada)

    1998-03-12

    This work examines the effects of connate water on the unstable displacement patterns and fractional oil recoveries observed when simulated secondary and tertiary oil displacement processes are conducted in the laboratory. Three displacement systems were investigated; a non-reacting system without surfactant (water displacing non-acidic paraffin oil), a non-reacting system with externally added surfactant (sodium dodecyl sulfate solution displacing non-acidic paraffin oil), and a reacting system with internally generated surfactant (sodium hydroxide solution displacing acidified paraffin oil). A consolidated porous medium constructed of fused glass beads was used to simulate the underground oil reservoir. Each of the three basic displacement processes was conducted both in the absence and presence of connate water, and at three different flow rates. The results obtained indicate that the presence of connate water can exert a significant influence on the displacement pattern with the non-reacting systems, particularly at low flow rates. Some of these effects include an increase in the number of fingers and/or much thinner fingers with many tiny branches. At low flow rates, the presence of connate water tends to decrease the breakthrough oil recovery for the non-surfactant system, but increases the breakthrough recovery for the surfactant-containing systems. At high flow rates, connate water has a much less pronounced effect due to the dominance of viscous forces

  3. Pulmonary surfactant and lung transplantation

    NARCIS (Netherlands)

    Erasmus, Michiel Elardus

    1997-01-01

    Pulmonary surfactant lowers the surface tension at the air-water interface inside the alveolus. This is achieved by adsorption of surfactant phospholipids at the air-water interface, a process controlled by surfactant-associated proteins, such as SP-A. In this way, surfactant prevents collapse of th

  4. Insurance against climate change and flood risk: Insurability and decision processes of insurers

    Science.gov (United States)

    Hung, Hung-Chih; Hung, Jia-Yi

    2016-04-01

    1. Background Major portions of the Asia-Pacific region is facing escalating exposure and vulnerability to climate change and flood-related extremes. This highlights an arduous challenge for public agencies to improve existing risk management strategies. Conventionally, governmental funding was majorly responsible and accountable for disaster loss compensation in the developing countries in Asia, such as Taiwan. This is often criticized as an ineffective and inefficient measure of dealing with flood risk. Flood insurance is one option within the toolkit of risk-sharing arrangement and adaptation strategy to flood risk. However, there are numerous potential barriers for insurance companies to cover flood damage, which would cause the flood risk is regarded as uninsurable. This study thus aims to examine attitudes within the insurers about the viability of flood insurance, the decision-making processes of pricing flood insurance and their determinants, as well as to examine potential solutions to encourage flood insurance. 2. Methods and data Using expected-utility theory, an insurance agent-based decision-making model was developed to examine the insurers' attitudes towards the insurability of flood risk, and to scrutinize the factors that influence their decisions on flood insurance premium-setting. This model particularly focuses on how insurers price insurance when they face either uncertainty or ambiguity about the probability and loss of a particular flood event occurring. This study considers the factors that are expected to affect insures' decisions on underwriting and pricing insurance are their risk perception, attitudes towards flood insurance, governmental measures (e.g., land-use planning, building codes, risk communication), expected probabilities and losses of devastating flooding events, as well as insurance companies' attributes. To elicit insurers' utilities about premium-setting for insurance coverage, the 'certainty equivalent,' 'probability

  5. Reservoir Characterization of Bridgeport and Cypress Sandstones in Lawrence Field Illinois to Improve Petroleum Recovery by Alkaline-Surfactant-Polymer Flood

    Energy Technology Data Exchange (ETDEWEB)

    Seyler, Beverly; Grube, John; Huff, Bryan; Webb, Nathan; Damico, James; Blakley, Curt; Madhavan, Vineeth; Johanek, Philip; Frailey, Scott

    2012-12-21

    Within the Illinois Basin, most of the oilfields are mature and have been extensively waterflooded with water cuts that range up to 99% in many of the larger fields. In order to maximize production of significant remaining mobile oil from these fields, new recovery techniques need to be researched and applied. The purpose of this project was to conduct reservoir characterization studies supporting Alkaline-Surfactant-Polymer Floods in two distinct sandstone reservoirs in Lawrence Field, Lawrence County, Illinois. A project using alkaline-surfactantpolymer (ASP) has been established in the century old Lawrence Field in southeastern Illinois where original oil in place (OOIP) is estimated at over a billion barrels and 400 million barrels have been recovered leaving more than 600 million barrels as an EOR target. Radial core flood analysis using core from the field demonstrated recoveries greater than 20% of OOIP. While the lab results are likely optimistic to actual field performance, the ASP tests indicate that substantial reserves could be recovered even if the field results are 5 to 10% of OOIP. Reservoir characterization is a key factor in the success of any EOR application. Reservoirs within the Illinois Basin are frequently characterized as being highly compartmentalized resulting in multiple flow unit configurations. The research conducted on Lawrence Field focused on characteristics that define reservoir compartmentalization in order to delineate preferred target areas so that the chemical flood can be designed and implemented for the greatest recovery potential. Along with traditional facies mapping, core analyses and petrographic analyses, conceptual geological models were constructed and used to develop 3D geocellular models, a valuable tool for visualizing reservoir architecture and also a prerequisite for reservoir simulation modeling. Cores were described and potential permeability barriers were correlated using geophysical logs. Petrographic analyses

  6. Migration Regularity and Influence Factors of Proppant in Formation Fracture during Base/Surfactant/Polymer Flooding%三元复合驱地层压裂支撑剂出砂程度及影响因素研究

    Institute of Scientific and Technical Information of China (English)

    郭琦; 牛丽伟; 彭占刚; 高立新; 卢祥国; 夏欢; 李国桥

    2016-01-01

    为揭示三元复合驱生产井压裂过程中的裂缝出砂规律,以裂缝出砂率为评价指标,在人造岩心裂缝内开展了三元复合驱地层中支撑剂出砂程度及影响因素研究.结果表明,随裂缝闭合应力和填砂浓度增加、注入排量减小,石英砂出砂率降低;与水驱相比,强碱三元复合驱出砂率较高,在注入排量为200和800 mL/min时,三元体系的出砂率分别是污水的3.29倍和1.84倍;与水平缝相比,垂直缝出砂率较高;驱替液类型与裂缝形态对耐碱树脂砂的出砂率无影响,注入排量200~800 mL/min时的出砂率均为0;将石英砂与核桃壳或碳纤维混合可以降低出砂率,其中“石英砂+核桃壳”组合效果优于“石英砂+碳纤维”组合.在三元复合驱时,宜采用耐碱树脂砂或“石英砂+核桃壳”作为支撑剂.%In view of the sand production in fracturing process of production well with strong base/surfactant/polymer (ASP) flooding,taking the sand production rate as evaluation index,the sand production degree and influence factor of ASP flooding in artificial core were studied.The results showed that with increasing closure stress of fracture and concentration of sand filling,as well as decreasing injection rate,the sand production rate decreased.The sand production rate of ASP flooding was higher than that of water flooding.When the injection rate Was 200 and 800 mL/min,the sand production rate of ASP was 3.29 times and 1.84 times of sewage' s,respectively.The sand production rate of vertically fracture was higher than that of horizontal fracture.The type of displacement fluid and fracture pattern had no influence on the sand production rate of alkali resistant resin sand,which was zero when injection rate was 200-800 mL/min.Mixing quartz sand with walnut shell or carbon fiber could reduce the sand production rate,and "quartz sand+walnut shell" had better effect than "quartz sand+carbon fiber".During the process of ASP flooding

  7. Vistula River bed erosion processes and their influence on Warsaw's flood safety

    Science.gov (United States)

    Magnuszewski, A.; Moran, S.

    2015-03-01

    Large cities have historically been well protected against floods as a function of their importance to society. In Warsaw, Poland, located on a narrow passage of the Vistula River valley, urban flood disasters were not unusual. Beginning at the end of the 19th century, the construction of river embankment and training works caused the narrowing of the flood passage path in the downtown reach of the river. The process of bed erosion lowered the elevation of the river bed by 205 cm over the 20th century, and the consequences of bed lowering are reflected by the rating curve change. Conditions of the flood passage have been analysed by the CCHE2D hydrodynamic model both in retro-modelling and scenario simulation modelling. The high water mark of the 1844 flood and iterative calculations in retro-modelling made possible estimation of the discharge, Q = 8250 m3 s-1. This highest observed historical flood in a natural river has been compared to recent conditions of the Vistula River in Warsaw by scenario modelling. The result shows dramatic changes in water surface elevation, velocities, and shear stress. The vertical velocity in the proximity of Port Praski gauge at km 513 can reach 3.5 m s-1, a very high value for a lowland river. The average flow conveyance is improving due to channel erosion but also declining in the case of extreme floods due to high resistance from vegetation on the flood plains.

  8. Vistula River bed erosion processes and their influence on Warsaw’s flood safety

    Directory of Open Access Journals (Sweden)

    A. Magnuszewski

    2015-03-01

    Full Text Available Large cities have historically been well protected against floods as a function of their importance to society. In Warsaw, Poland, located on a narrow passage of the Vistula River valley, urban flood disasters were not unusual. Beginning at the end of the 19th century, the construction of river embankment and training works caused the narrowing of the flood passage path in the downtown reach of the river. The process of bed erosion lowered the elevation of the river bed by 205 cm over the 20th century, and the consequences of bed lowering are reflected by the rating curve change. Conditions of the flood passage have been analysed by the CCHE2D hydrodynamic model both in retro-modelling and scenario simulation modelling. The high water mark of the 1844 flood and iterative calculations in retro-modelling made possible estimation of the discharge, Q = 8250 m3 s−1. This highest observed historical flood in a natural river has been compared to recent conditions of the Vistula River in Warsaw by scenario modelling. The result shows dramatic changes in water surface elevation, velocities, and shear stress. The vertical velocity in the proximity of Port Praski gauge at km 513 can reach 3.5 m s−1, a very high value for a lowland river. The average flow conveyance is improving due to channel erosion but also declining in the case of extreme floods due to high resistance from vegetation on the flood plains.

  9. Adsorption of surfactants on sand surface in enhanced oil recovery: Isotherms, kinetics and thermodynamic studies

    Energy Technology Data Exchange (ETDEWEB)

    Bera, Achinta; Kumar, T.; Ojha, Keka; Mandal, Ajay, E-mail: mandal_ajay@hotmail.com

    2013-11-01

    Adsorption of surfactants onto reservoir rock surface may result in the loss and reduction of their concentrations in surfactant flooding, which may render them less efficient or ineffective in practical applications of enhanced oil recovery (EOR) techniques. Surfactant flooding for EOR received attraction due to its ability to increase the displacement efficiency by lowering the interfacial tension between oil and water and mobilizing the residual oil. This article highlights the adsorption of surfactants onto sand surface with variation of different influencing factors. It has been experimentally found that adsorption of cationic surfactant on sand surface is more and less for anionic surfactant, while non-ionic surfactant shows intermediate behaviour. X-ray diffraction (XRD) study of clean sand particles has been made to determine the main component present in the sand particles. The interaction between sand particles and surfactant has been studied by Fourier Transform Infrared (FTIR) Spectroscopy of the sand particles before and after aging with surfactant. Salinity plays an important role in adsorption of anionic surfactant. Batch experiments were also performed to understand the effects of pH and adsorbent dose on the sorption efficiency. The sand particles exhibited high adsorption efficiency at low pH for anionic and nonionic surfactants. But opposite trend was found for cationic surfactant. Adsorption data were analyzed by fitting with Langmuir, Freundlich, Redlich-Peterson, and Sips isotherm models. Results show that the Langmuir isotherm and pseudo-second order kinetics models suit the equilibrium and kinetics of adsorption on sand surface. Thermodynamics feasibility of the adsorption process was also studied to verify the spontaneity of the process.

  10. GIS-based flood risk model evaluated by Fuzzy Analytic Hierarchy Process (FAHP)

    Science.gov (United States)

    Sukcharoen, Tharapong; Weng, Jingnong; Teetat, Charoenkalunyuta

    2016-10-01

    Over the last 2-3 decades, the economy of many countries around the world has been developed rapidly but it was unbalanced development because of expecting on economic growth only. Meanwhile it lacked of effective planning in the use of natural resources. This can significantly induce climate change which is major cause of natural disaster. Hereby, Thailand has also suffered from natural disaster for ages. Especially, the flood which is most hazardous disaster in Thailand can annually result in the great loss of life and property, environment and economy. Since the flood management of country is inadequate efficiency. It is unable to support the flood analysis comprehensively. This paper applied Geographic Information System and Multi-Criteria Decision Making to create flood risk model at regional scale. Angthong province in Thailand was used as the study area. In practical process, Fuzzy logic technique has been used to improve specialist's assessment by implementing with Fuzzy membership because human decision is flawed under uncertainty then AHP technique was processed orderly. The hierarchy structure in this paper was categorized the spatial flood factors into two levels as following: 6 criteria (Meteorology, Geology, Topography, Hydrology, Human and Flood history) and 8 factors (Average Rainfall, Distance from Stream, Soil drainage capability, Slope, Elevation, Land use, Distance from road and Flooded area in the past). The validity of the pair-wise comparison in AHP was shown as C.R. value which indicated that the specialist judgment was reasonably consistent. FAHP computation result has shown that the first priority of criteria was Meteorology. In addition, the Rainfall was the most influencing factor for flooding. Finally, the output was displayed in thematic map of Angthong province with flood risk level processed by GIS tools. The map was classified into: High Risk, Moderate Risk and Low Risk (13.20%, 75.58%, and 11.22% of total area).

  11. Vistula River bed erosion processes and their influence on Warsaw’s flood safety

    OpenAIRE

    Magnuszewski, A.; Moran, S

    2015-01-01

    Large cities have historically been well protected against floods as a function of their importance to society. In Warsaw, Poland, located on a narrow passage of the Vistula River valley, urban flood disasters were not unusual. Beginning at the end of the 19th century, the construction of river embankment and training works caused the narrowing of the flood passage path in the downtown reach of the river. The process of bed erosion lowered the elevation of the river bed by 205 cm over the 20t...

  12. Polymeric surfactants for enhanced oil recovery : A review

    NARCIS (Netherlands)

    Raffa, Patrizio; Broekhuis, Antonius A.; Picchioni, Francesco

    Chemical enhanced oil recovery (EOR) is surely a topic of interest, as conventional oil resources become more scarce and the necessity of exploiting heavy and unconventional oils increases. EOR methods based on polymer flooding, surfactant-polymer flooding and alkali-surfactant-polymer flooding are

  13. Polymeric surfactants for enhanced oil recovery : A review

    NARCIS (Netherlands)

    Raffa, Patrizio; Broekhuis, Antonius A.; Picchioni, Francesco

    2016-01-01

    Chemical enhanced oil recovery (EOR) is surely a topic of interest, as conventional oil resources become more scarce and the necessity of exploiting heavy and unconventional oils increases. EOR methods based on polymer flooding, surfactant-polymer flooding and alkali-surfactant-polymer flooding are

  14. Polymeric surfactants for enhanced oil recovery : A review

    NARCIS (Netherlands)

    Raffa, Patrizio; Broekhuis, Antonius A.; Picchioni, Francesco

    2016-01-01

    Chemical enhanced oil recovery (EOR) is surely a topic of interest, as conventional oil resources become more scarce and the necessity of exploiting heavy and unconventional oils increases. EOR methods based on polymer flooding, surfactant-polymer flooding and alkali-surfactant-polymer flooding are

  15. Logically Sensing Aggregate Process and Discriminating SDS from Other Surfactants with the Assistance of BSA

    Institute of Scientific and Technical Information of China (English)

    钱俊红; 徐玉芳; 钱旭红

    2012-01-01

    An amphiphilic fluorescent probe, 3-dodecylamino dihydrogen imidazo[2,l-a]benz[de]isoquinolin-7-one (compound 3), was used to sense the aggregate formation process of bovine serum albumine (BSA), sodium dode- cyl sulfate (SDS) and their mixed system. The fluorescence intensity of 3 was significantly affected by the adding order of SDS and BSA, and SDS can be distinguished from other surfactants with the aid of BSA, but only when 3 is allowed to interact with BSA first. The results revealed that compound 3 is preferentially sited in the hydrophobic region of BSA, and thermodynamically in SDS-BSA mixed aggregate. Sodium phosphate buffer solution (PBS) and BSA played important but distinct roles in distinguishing SDS micelle from the others.

  16. Characterization and antibacterial properties of stable silver substituted hydroxyapatite nanoparticles synthesized through surfactant assisted microwave process

    Energy Technology Data Exchange (ETDEWEB)

    Iqbal, Nida [Medical Implant Technology Group (MEDITEG), Faculty of Bioscience and Medical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Abdul Kadir, Mohammed Rafiq, E-mail: rafiq@biomedical.utm.my [Medical Implant Technology Group (MEDITEG), Faculty of Bioscience and Medical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Nik Malek, Nik Ahmad Nazim [Faculty of Bioscience and Medical Engineering (FBME), Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Mahmood, Nasrul Humaimi Bin [Medical Implant Technology Group (MEDITEG), Faculty of Bioscience and Medical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor Darul Takzim (Malaysia); Murali, Malliga Raman; Kamarul, T. [Tissue Engineering Group, NOCERAL, Department of Orthopaedic Surgery, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2013-09-01

    Highlights: • Stable nano sized silver substitute hydroxyapatite is prepared under surfactant assisted microwave process at 600 W power for 7 min. • The nanoparticles are in the size range of 58–72 nm and exert uniform elongated spheroid morphology. • Increase in silver concentration resulted in better dielectric properties. • Good antibacterial activity and silver release. - Abstract: The present study reports a relatively simple method for the synthesis of stable silver substituted hydroxyapatite nanoparticles with controlled morphology and particle size. In order to achieve this, CTAB is included as a surfactant in the microwave refluxing process (600 W for 7 min). The nanoparticles produced with different silver ion concentrations (0.05, 0.1 and 0.2 wt%) were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDX) and Brunauer–Emmett–Teller (BET) analysis. XRD and FTIR analyses reveal that the Ag-HA nanoparticles were phase pure at 1000 °C. FESEM images showed that the produced nanoparticles are in the size range of 58–72 nm and exert uniform elongated spheroid morphology. The dielectric properties suggest that the increase in dielectric constant (ε′) and dissipation factor (D) values with increasing Ag concentrations. Antibacterial performance of the Ag-HA samples elucidated using disk diffusion technique (DDT) and minimum inhibitory concentration (MIC) demonstrates anti-bacterial activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa and Escherichia coli. This effect was dose dependent and was more pronounced against Gram-negative bacteria than Gram-positive organisms.

  17. Novel antifoam for fermentation processes: fluorocarbon-hydrocarbon hybrid unsymmetrical bolaform surfactant.

    Science.gov (United States)

    Calik, Pinar; Ileri, Nazar; Erdinç, Burak I; Aydogan, Nihal; Argun, Muharrem

    2005-09-13

    As foaming appears as a problem in chemical and fermentation processes that inhibits reactor performance, the eminence of a novel fluorocarbon-hydrocarbon unsymmetrical bolaform (FHUB: OH(CH2)11N+(C2H4)2(CH2)2(CF2)5CF3 I-) surfactant as an antifoaming agent as well as a foam-reducing agent was investigated and compared with other surfactants and a commercial antifoaming agent. The surface elasticity of FHUB was determined as 4 mN/m, indicating its high potential on thinning of the foam film. The interactions between FHUB and the microoganism were investigated in a model fermentation process related with an enzyme production by recombinant Escherichia coli, in V = 3.0 dm3 bioreactor systems with V(R) = 1.65 dm3 working volume at air inlet rate of Q(o)/V(R) = 0.5 dm3 dm(-3) min(-1) and agitation rate of N = 500 min(-1) oxygen transfer conditions, at T = 37 degrees C, pH(o) = 7.2, and C(FHUB) = 0 and 0.1 mM, in a glucose-based defined medium. As FHUB did not influence the metabolism, specific enzyme activity values obtained with and without FHUB were close to each other; however, because of the slight decrease in oxygen transfer coefficient, slightly lower volumetric enzyme activity and cell concentrations were obtained. However, when FHUB is compared with widely used silicon oil based Antifoam A, with the use of the FHUB, higher physical oxygen transfer coefficient (K(L)a) values are obtained. Moreover, as the amount required for the foam control is very low, minute changes in the working volume of the bioreactor were obtained indicating the high potential of the use of FHUB as an antifoaming agent as well as a foam-reducing agent.

  18. How Multilevel Societal Learning Processes Facilitate Transformative Change: A Comparative Case Study Analysis on Flood Management

    Directory of Open Access Journals (Sweden)

    Claudia Pahl-Wostl

    2013-12-01

    Full Text Available Sustainable resources management requires a major transformation of existing resource governance and management systems. These have evolved over a long time under an unsustainable management paradigm, e.g., the transformation from the traditionally prevailing technocratic flood protection toward the holistic integrated flood management approach. We analyzed such transformative changes using three case studies in Europe with a long history of severe flooding: the Hungarian Tisza and the German and Dutch Rhine. A framework based on societal learning and on an evolutionary understanding of societal change was applied to identify drivers and barriers for change. Results confirmed the importance of informal learning and actor networks and their connection to formal policy processes. Enhancing a society's capacity to adapt is a long-term process that evolves over decades, and in this case, was punctuated by disastrous flood events that promoted windows of opportunity for change.

  19. Determination of Surface Tension of Surfactant Solutions through Capillary Rise Measurements: An Image-Processing Undergraduate Laboratory Experiment

    Science.gov (United States)

    Huck-Iriart, Cristia´n; De-Candia, Ariel; Rodriguez, Javier; Rinaldi, Carlos

    2016-01-01

    In this work, we described an image processing procedure for the measurement of surface tension of the air-liquid interface using isothermal capillary action. The experiment, designed for an undergraduate course, is based on the analysis of a series of solutions with diverse surfactant concentrations at different ionic strengths. The objective of…

  20. Surfactant-Polymer Interaction for Improved Oil Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Gabitto, Jorge; Mohanty, Kishore K.

    2002-01-07

    The goal of this research was to use the interaction between a surfactant and a polymer for efficient displacement of tertiary oil by improving slug integrity, oil solubility in the displacing fluid and mobility control. Surfactant-polymer flooding has been shown to be highly effective in laboratory-scale linear floods. The focus of this proposal is to design an inexpensive surfactant-polymer mixture that can efficiently recover tertiary oil by avoiding surfactant slug degradation and viscous/heterogeneity fingering.

  1. Voice-enabled Knowledge Engine using Flood Ontology and Natural Language Processing

    Science.gov (United States)

    Sermet, M. Y.; Demir, I.; Krajewski, W. F.

    2015-12-01

    The Iowa Flood Information System (IFIS) is a web-based platform developed by the Iowa Flood Center (IFC) to provide access to flood inundation maps, real-time flood conditions, flood forecasts, flood-related data, information and interactive visualizations for communities in Iowa. The IFIS is designed for use by general public, often people with no domain knowledge and limited general science background. To improve effective communication with such audience, we have introduced a voice-enabled knowledge engine on flood related issues in IFIS. Instead of navigating within many features and interfaces of the information system and web-based sources, the system provides dynamic computations based on a collection of built-in data, analysis, and methods. The IFIS Knowledge Engine connects to real-time stream gauges, in-house data sources, analysis and visualization tools to answer natural language questions. Our goal is the systematization of data and modeling results on flood related issues in Iowa, and to provide an interface for definitive answers to factual queries. The goal of the knowledge engine is to make all flood related knowledge in Iowa easily accessible to everyone, and support voice-enabled natural language input. We aim to integrate and curate all flood related data, implement analytical and visualization tools, and make it possible to compute answers from questions. The IFIS explicitly implements analytical methods and models, as algorithms, and curates all flood related data and resources so that all these resources are computable. The IFIS Knowledge Engine computes the answer by deriving it from its computational knowledge base. The knowledge engine processes the statement, access data warehouse, run complex database queries on the server-side and return outputs in various formats. This presentation provides an overview of IFIS Knowledge Engine, its unique information interface and functionality as an educational tool, and discusses the future plans

  2. Surfactant modified MgFe{sub 2}O{sub 4} nanopowders by reverse micelle processing: Effect of water to surfactant ratio (R) on the particle size and magnetic property

    Energy Technology Data Exchange (ETDEWEB)

    Chandradass, J.; Jadhav, Arvind H. [Energy and Environment Fusion Technology Center, Department of Environmental Engineering and Biotechnology, Myongji University, Yongin, Kyonggi-do 449-728 (Korea, Republic of); Kim, Hern, E-mail: hernkim@mju.ac.kr [Energy and Environment Fusion Technology Center, Department of Environmental Engineering and Biotechnology, Myongji University, Yongin, Kyonggi-do 449-728 (Korea, Republic of)

    2012-01-15

    Nanoparticles of surfactant modified MgFe{sub 2}O{sub 4} have been synthesized by reverse micelle processing using tertiary system of heptane/Igepal CO 520/H{sub 2}O. The effect of water to surfactant ratio on the particle size and magnetic property has been studied. X-ray diffraction analysis confirms that MgFe{sub 2}O{sub 4} nanoparticles are crystalline in nature with cubic spinel structure. The average particle size increases with increase in water to surfactant ratio. The Fourier transform infrared (FTIR) analysis confirms that the surface of MgFe{sub 2}O{sub 4} nanoparticles was coated with surfactants. The saturation magnetization ranged from 14.4 to 40.05 emu/g was measured by Superconducting Quantum Interference Device Magnetometry (SQUID).

  3. FLCNDEMF: An Event Metamodel for Flood Process Information Management under the Sensor Web Environment

    Directory of Open Access Journals (Sweden)

    Nengcheng Chen

    2015-06-01

    Full Text Available Significant economic losses, large affected populations, and serious environmental damage caused by recurrent natural disaster events (NDE worldwide indicate insufficiency in emergency preparedness and response. The barrier of full life cycle data preparation and information support is one of the main reasons. This paper adopts the method of integrated environmental modeling, incorporates information from existing event protocols, languages, and models, analyzes observation demands from different event stages, and forms the abstract full life cycle natural disaster event metamodel (FLCNDEM based on meta-object facility. Then task library and knowledge base for floods are built to instantiate FLCNDEM, forming the FLCNDEM for floods (FLCNDEMF. FLCNDEMF is formalized according to Event Pattern Markup Language, and a prototype system, Natural Disaster Event Manager, is developed to assist in the template-based modeling and management. The flood in Liangzi (LZ Lake of Hubei, China on 16 July 2010 is adopted to illustrate how to apply FLCNDEM in real scenarios. FLCNDEM-based modeling is realized, and the candidate remote sensing (RS dataset for different observing missions are provided for LZ Lake flood. Taking the mission of flood area extraction as an example, the appropriate RS data are selected via the model of simplified general perturbation version 4, and the flood area in different phases are calculated and displayed on the map. The phase-based modeling and visualization intuitively display the spatial-temporal distribution and the evolution process of the LZ Lake flood, and it is of great significance for flood responding. In addition, through the extension mechanism, FLCNDEM can also be applied in other environmental applications, providing important support for full life cycle information sharing and rapid responding.

  4. REMOVAL OF PHENOL AND SURFACTANT FROM LANDFILL LEACHATE BY COAGULATION-FLOCCULATION PROCESS

    Directory of Open Access Journals (Sweden)

    H. BAKRAOUY

    2016-02-01

    Full Text Available Following the action of rainfall and natural fermentation, the stored waste produces a liquid fraction called leachate. This leachate is rich in organic matter (biodegradable but also refractory and trace elements. There are many techniques of treating the leachate, in particular, biological, physicochemical, membrane processes. The choice of a technique instead of another depends on several parameters including: the age of the leachate, composition... In this work we applied a coagulation-flocculation process to treat intermediate landfill leachate of Rabat city with a combined ferric chloride coagulant and a polymer flocculant. We were inspired by full factorial design, including twenty five experiments, to determine optimal dosages of coagulant and flocculant. We operate at pH 8.4, the best removal efficiencies obtained were 88 % for Turbidity, 98 % for Phenol and 82 % for surfactant. The optimum dosages values determined by this study were 13.2 g∙L-1 of coagulant, 62 mL∙L-1 of flocculant.

  5. Combined Fenton oxidation and aerobic biological processes for treating a surfactant wastewater containing abundant sulfate.

    Science.gov (United States)

    Wang, Xiao-Jun; Song, Yang; Mai, Jun-Sheng

    2008-12-30

    The present study is to investigate the treatment of a surfactant wastewater containing abundant sulfate by Fenton oxidation and aerobic biological processes. The operating conditions have been optimized. Working at an initial pH value of 8, a Fe2+ dosage of 600mgL(-1) and a H2O2 dosage of 120mgL(-1), the chemical oxidation demand (COD) and linear alkylbenzene sulfonate (LAS) were decreased from 1500 and 490mgL(-1) to 230 and 23mgL(-1) after 40min of Fenton oxidation, respectively. Advanced oxidation pretreatment using Fenton reagent was very effective at enhancing the biodegradability of this kind of wastewater. The wastewater was further treated by a bio-chemical treatment process based on an immobilized biomass reactor with a hydraulic detention time (HRT) of 20h after Fenton oxidation pretreatment under the optimal operating conditions. It was found that the COD and LAS of the final effluent were less than 100 and 5mgL(-1), corresponding to a removal efficiencies of over 94% and 99%, respectively.

  6. Performance of the Biocompatible Surfactant Tween 80, for the Formation of Microemulsions Suitable for New Pharmaceutical Processing

    Directory of Open Access Journals (Sweden)

    Cristina Prieto

    2013-01-01

    Full Text Available The aim of this work was to investigate the phase behaviour and the structure of the n-hexane/water emulsions based on a nonionic, nontoxic and biocompatible surfactant, Tween 80. This system is of interest for new pharmaceutical techniques based on supercritical fluids to form nano- and encapsulated particles. However, it showed a lack of stability denoted by large areas of macroemulsion. For this reason, the effect of additives (alcohols and brine and external variables (temperature were explored. The replacement of water by brine caused negligible impact due to the nonionic character of Tween 80. On the contrary, the presence of an alcohol (ethanol or 1-butanol enhanced the solubility of the surfactant in the oil phase and decreased the mixture viscosity, resulting in improved surface activity. Similar results were obtained by raising the temperature until the cloud point was reached (60°C. With these modifications, microemulsions at relatively low concentrations of surfactant (around 30% and within a broad interval of compositions could be obtained, widening their possible use in pharmaceuticals manufacturing (such as controlled drug delivery, enzymatic reactions, or excipient processing. The understanding of the surfactant performance could be further used to substitute the n-hexane by a greener solvent, such as supercritical CO2.

  7. Multiple effects of sediment transport and geomorphic processes within flood events:Modelling and understanding

    Institute of Scientific and Technical Information of China (English)

    Mingfu Guan n; NigeLG. Wright; P. AndreWSleigh

    2015-01-01

    Flood events can induce considerable sediment transport which in turn influences flow dynamics. This study investigates the multiple effects of sediment transport in floods through modelling a series of hydraulic scenarios, including small-scale experimental cases and a full-scale glacial outburst flood. A non-uniform, layer-based morphodynamic model is presented which is composed of a combination of three modules: a hydrodynamic model governed by the two-dimensional shallow water equations involving sediment effects;a sediment transport model controlling the mass conservation of sediment;and a bed deformation model for updating the bed elevation. The model is solved by a second-order Godunov-type numerical scheme. Through the modelling of the selected sediment-laden flow events, the interactions of flow and sediment transport and geomorphic processes within flood events are elucidated. It is found that the inclusion of sediment transport increases peak flow discharge, water level and water depth in dam-break flows over a flat bed. For a partial dam breach, sediment material has a blockage effect on the flood dynamics. In comparison with the‘sudden collapse’ of a dam, a gradual dam breach significantly delays the arrival time of peak flow, and the flow hydrograph is changed similarly. Considerable bed erosion and deposition occur within the rapid outburst flood, which scours the river channel severely. It is noted that the flood propagation is accelerated after the incorporation of sediment transport, and the water level in most areas of the channel is reduced.

  8. Assessment of the effects of multiple extreme floods on flow and transport processes under competing flood protection and environmental management strategies.

    Science.gov (United States)

    Tu, Tongbi; Carr, Kara J; Ercan, Ali; Trinh, Toan; Kavvas, M Levent; Nosacka, John

    2017-07-11

    Extreme floods are regarded as one of the most catastrophic natural hazards and can result in significant morphological changes induced by pronounced sediment erosion and deposition processes over the landscape. However, the effects of extreme floods of different return intervals on the floodplain and river channel morphological evolution with the associated sediment transport processes are not well explored. Furthermore, different basin management action plans, such as engineering structure modifications, may also greatly affect the flood inundation, sediment transport, solute transport and morphological processes within extreme flood events. In this study, a coupled two-dimensional hydrodynamic, sediment transport and morphological model is applied to evaluate the impact of different river and basin management strategies on the flood inundation, sediment transport dynamics and morphological changes within extreme flood events of different magnitudes. The 10-year, 50-year, 100-year and 200-year floods are evaluated for the Lower Cache Creek system in California under existing condition and a potential future modification scenario. Modeling results showed that select locations of flood inundation within the study area tend to experience larger inundation depth and more sediment is likely to be trapped in the study area under potential modification scenario. The proposed two dimensional flow and sediment transport modeling approach implemented with a variety of inflow conditions can provide guidance to decision-makers when considering implementation of potential modification plans, especially as they relate to competing management strategies of large water bodies, such as the modeling area in this study. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. A novel liquid/liquid extraction process composed of surfactant and acetonitrile for purification of polygalacturonase enzyme from Durio zibethinus.

    Science.gov (United States)

    Amid, Mehrnoush; Manap, Yazid; Azmira, Farhana; Hussin, Muhaini; Sarker, Zaidul Islam

    2015-07-01

    Polygalacturonase is one of the important enzymes used in various industries such as food, detergent, pharmaceutical, textile, pulp and paper. A novel liquid/liquid extraction process composed of surfactant and acetonitrile was employed for the first time to purify polygalacturonase from Durio zibethinus. The influences of different parameters such as type and concentration of surfactants, concentrations of acetonitrile and composition of surfactant/acetonitrile on partitioning behavior and recovery of polygalacturonase was investigated. Moreover, the effect of pH of system and crude load on purification fold and yield of purified polygalacturonase were studied. The results of the experiment indicated the polygalacturonase was partitioned into surfactant top rich phase with impurities being partitioned into acetonitrile bottom rich phase in the novel method of liquid/liquid process composed of 23% (w/w) Triton X-100 and 19% (w/w) acetonitrile, at 55.6% of TLL (tie line length) crude load of 25% (w/w) at pH 6.0. Recovery and recycling of components also was measured in each successive step of liquid/liquid extraction process. The enzyme was successfully recovered by the method with a high purification factor of 14.3 and yield of 97.3% while phase components were also recovered and recycled above 95%. This study demonstrated that the novel method of liquid/liquid extraction process can be used as an efficient and economical extraction method rather than the traditional methods of extraction for the purification and recovery of the valuable enzyme.

  10. SURFACTANTS IN LUBRICATION

    Science.gov (United States)

    Surfactants are one of the most widely applied materials by consumers and industry. The application areas for surfactants span from everyday mundane tasks such as cleaning, to highly complex processes involving the formulation of pharmaceuticals, foods, pesticides, lubricants, etc. Even though sur...

  11. Quantifying the effect of sea level rise and flood defence - a point process perspective on coastal flood damage

    Science.gov (United States)

    Boettle, M.; Rybski, D.; Kropp, J. P.

    2016-02-01

    In contrast to recent advances in projecting sea levels, estimations about the economic impact of sea level rise are vague. Nonetheless, they are of great importance for policy making with regard to adaptation and greenhouse-gas mitigation. Since the damage is mainly caused by extreme events, we propose a stochastic framework to estimate the monetary losses from coastal floods in a confined region. For this purpose, we follow a Peak-over-Threshold approach employing a Poisson point process and the Generalised Pareto Distribution. By considering the effect of sea level rise as well as potential adaptation scenarios on the involved parameters, we are able to study the development of the annual damage. An application to the city of Copenhagen shows that a doubling of losses can be expected from a mean sea level increase of only 11 cm. In general, we find that for varying parameters the expected losses can be well approximated by one of three analytical expressions depending on the extreme value parameters. These findings reveal the complex interplay of the involved parameters and allow conclusions of fundamental relevance. For instance, we show that the damage typically increases faster than the sea level rise itself. This in turn can be of great importance for the assessment of sea level rise impacts on the global scale. Our results are accompanied by an assessment of uncertainty, which reflects the stochastic nature of extreme events. While the absolute value of uncertainty about the flood damage increases with rising mean sea levels, we find that it decreases in relation to the expected damage.

  12. Flood vulnerability assessment of residential buildings by explicit damage process modelling

    DEFF Research Database (Denmark)

    Custer, Rocco; Nishijima, Kazuyoshi

    2015-01-01

    The present paper introduces a vulnerability modelling approach for residential buildings in flood. The modelling approach explicitly considers relevant damage processes, i.e. water infiltration into the building, mechanical failure of components in the building envelope and damage from water con...

  13. Separation process for lanthanides based on solvation properties of non ionic surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Draye, M.; Favre-Reguillon, A.; Foos, J.; Cote, G

    2004-07-01

    In the present study, cloud-point extraction is used with a lipophilic chelating agent (8-hydroxyquinoline) to extract and separate lanthanum (III) and gadolinium (III) from an aqueous solution. The methodology used is based on the formation of lanthanide (III) organic complexes that are soluble in a micellar phase of non-ionic surfactant. The lanthanide (III) complexes are then extracted into the surfactant-rich phase at a temperature above the cloud-point temperature. The cloud-point temperature, the structure of the lipophilic part of the nonionic surfactant and the chelating agent - metal molar ratio are identified as factors determining the extraction efficiency and selectivity. With Triton X-114, high selectivity and decontamination factor for Gd(III) is observed indicating that micelle mediated extraction involving cloud-point extraction is promising for the specific separation of actinide ions from nuclear waste solution. (authors)

  14. Fabrication of Pd/Pd-Alloy Films by Surfactant Induced Electroless Plating for Hydrogen Separation from Advanced Coal Gasification Processes

    Energy Technology Data Exchange (ETDEWEB)

    Ilias, Shamsuddin; Kumar, Dhananjay

    2012-07-31

    Dense Pd, Pd-Cu and Pd-Ag composite membranes on microporous stainless steel substrate (MPSS) were fabricated by a novel electroless plating (EP) process. In the conventional Pd-EP process, the oxidation-reduction reactions between Pd-complex and hydrazine result in an evolution of NH{sub 3} and N{sub 2} gas bubbles. When adhered to the substrate surface and in the pores, these gas bubbles hinder uniform Pd-film deposition which results in dendrite growth leading to poor film formation. This problem was addressed by introducing cationic surfactant in the electroless plating process known as surfactant induced electroless plating (SIEP). The unique features of this innovation provide control of Pd-deposition rate, and Pd-grain size distribution. The surfactant molecules play an important role in the EP process by tailoring grain size and the process of agglomeration by removing tiny gas bubbles through adsorption at the gas-liquid interface. As a result surfactant can tailor a nanocrystalline Pd, Cu and Ag deposition in the film resulting in reduced membrane film thickness. Also, it produces a uniform, agglomerated film structure. The Pd-Cu and Pd-Ag membranes on MPSS support were fabricated by sequential deposition using SIEP method. The pre- and post-annealing characterizations of these membranes (Pd, Pd-Cu and Pd-Ag on MPSS substrate) were carried out by SEM, EDX, XRD, and AFM studies. The SEM images show significant improvement of the membrane surface morphology, in terms of metal grain structures and grain agglomeration compared to the membranes fabricated by conventional EP process. The SEM images and helium gas-tightness studies indicate that dense and thinner films of Pd, Pd-Cu and Pd-Ag membranes can be produced with shorter deposition time using surfactant. H{sub 2} Flux through the membranes fabricated by SIEP shows large improvement compared to those by CEP with comparable permselectivity. Pd-MPSS composite membrane was subjected to test for long term

  15. Processes and Geomorphological Impacts of an Extreme Flash Flood Event in SE Spain

    Science.gov (United States)

    Hooke, J.

    2015-12-01

    A major flash flood event took place on 28 September, 2012 in SE Spain, resulting in 10 fatalities and much damage to infrastructure regionally. The flood affected long-term monitoring sites in two catchments in which morphological changes and flow dynamics of these ephemeral channels were being measured. Thus detailed data on channel state prior to the flood were available. The flood event in the Nogalte catchment was extreme in its peak flow, rate of rise and unit runoff. The catchment has steep relief and much bare soil under almond groves, resulting in high sediment supply. The channel is confined in places, but mostly wide and braided, composed of loose gravel and occupying much of the valley floor. Flow was spatially continuous, with high connectivity throughout the catchment. The flood effects were net depositional in the monitored sites, with massive sedimentation on the channel bars. Vegetation was destroyed. Bank erosion and destruction of embankments took place in some locations. Hydraulic calculations indicate very high velocities, stream power and Froude numbers. Modelling and field evidence demonstrate extremely high sediment competence and sediment loadings. The influence of the event dynamics on processes and net outcomes is discussed. The impacts are compared with other events in this and neighbouring catchments. Overall, the event in the Nogalte did not alter the morphology markedly in spite of its extreme characteristics. It is suggested that these valley floors are adapted to this type of flash flood but that flows of such force and magnitude need to be allowed for in management in such an environment.

  16. Improving the quality of patchouli oil by adsorption process using surfactant modified of natural zeolite

    Science.gov (United States)

    Kuntari, Purbaningtias, Tri Esti; Wiyantoko, Bayu; Kurniawati, Puji; Prasetyoko, Didik; Suprapto

    2017-03-01

    This research concerns with the development of natural material i.e. natural zeolite. Natural zeolite were modified by surfactant treatment. Material modification has been done using cetyltrimethyllammonium bromide as cationic surfactant for mesopore template. The physicochemical characters of natural material modified and unmodified was investigated by using XRD, FTIR, nitrogen physisorption, and SEM-EDX. The XRD was used to show crystallinity structure of natural material modified and unmodified. Surfactant treatment caused decreasing crystallinity of natural zeolite. The FTIR spectra showed characteristic peaks for natural zeolite modified and unmodified, the bands around 3400-3500 cm-1 and 1635-1641 cm-1 correspond to adsorbed water and bands around finger print area were characteristic for silica and alumina. Meanwhile physisorption nitrogen profiles gave information that the pore modification by surfactant. The morphologies of natural material modified and unmodified as well as chemical composition of the particles were shown by SEM-EDX. The usage of modified material decrease acidity number into 19.47% than unmodified material, which is 7,62%. The GC analysis showed that percentage of patchouli alcohol increases and new peaks were not identified indicated there was not any reaction appeared.

  17. CHARACTERIZATION OF PHASE AND EMULSION BEHAVIOR, SURFACTANT RETENTION, AND OIL RECOVERY FOR NOVEL ALCOHOL ETHOXYCARBOXYLATE SURFACTANTS

    Energy Technology Data Exchange (ETDEWEB)

    Lebone T. Moeti; Ramanathan Sampath

    2001-09-28

    This final technical report describes work performed under DOE Grant No. DE-FG26-97FT97278 during the period October 01, 1997 to August 31, 2001 which covers the total performance period of the project. During this period, detailed information on optimal salinity, temperature, emulsion morphologies, effectiveness for surfactant retention and oil recovery was obtained for an Alcohol Ethoxycarboxylate (AEC) surfactant to evaluate its performance in flooding processes. Tests were conducted on several AEC surfactants and NEODOX (23-4) was identified as the most suitable hybrid surfactant that yielded the best proportion in volume for top, middle, and bottom phases when mixed with oil and water. Following the selection of this surfactant, temperature and salinity scans were performed to identify the optimal salinity and temperature, and the temperature and salinity intervals in which all three phases coexisted. NEODOX 23-4 formed three phases between 4 and 52.5 C. It formed an aqueous rich microemulsion phase at high temperatures and an oleic rich microemulsion phase at low temperatures--a characteristic of the ionic part of the surfactant. The morphology measurement system was set-up successfully at CAU. The best oil/water/surfactant system defined by the above phase work was then studied for emulsion morphologies. Electrical conductivities were measured for middle and bottom phases of the NEODOX 23-4/dodecane/10mM water system and by mixing measured volumes of the middle phase into a fixed volume of the bottom phase and vice versa at room temperature. Electrical conductivity of the mixture decreased as the fraction of volume of the middle phase was increased and vice versa. Also inversion phenomena was observed. These experiments were then repeated for bottom/middle (B/M) and middle/bottom (M/B) conjugate pair phases at 10, 15, 25, 30, 35, 40, and 45 C. Electrical conductivity measurements were then compared with the predictions of the conductivity model developed in

  18. A Multi-Scale Flood Monitoring System Based on Fully Automatic MODIS and TerraSAR-X Processing Chains

    Directory of Open Access Journals (Sweden)

    Enrico Stein

    2013-10-01

    Full Text Available A two-component fully automated flood monitoring system is described and evaluated. This is a result of combining two individual flood services that are currently under development at DLR’s (German Aerospace Center Center for Satellite based Crisis Information (ZKI to rapidly support disaster management activities. A first-phase monitoring component of the system systematically detects potential flood events on a continental scale using daily-acquired medium spatial resolution optical data from the Moderate Resolution Imaging Spectroradiometer (MODIS. A threshold set controls the activation of the second-phase crisis component of the system, which derives flood information at higher spatial detail using a Synthetic Aperture Radar (SAR based satellite mission (TerraSAR-X. The proposed activation procedure finds use in the identification of flood situations in different spatial resolutions and in the time-critical and on demand programming of SAR satellite acquisitions at an early stage of an evolving flood situation. The automated processing chains of the MODIS (MFS and the TerraSAR-X Flood Service (TFS include data pre-processing, the computation and adaptation of global auxiliary data, thematic classification, and the subsequent dissemination of flood maps using an interactive web-client. The system is operationally demonstrated and evaluated via the monitoring two recent flood events in Russia 2013 and Albania/Montenegro 2013.

  19. A Framework to Design and Optimize Chemical Flooding Processes

    Energy Technology Data Exchange (ETDEWEB)

    Mojdeh Delshad; Gary A. Pope Kamy Sepehrnoori

    2006-08-31

    The goal of this proposed research is to provide an efficient and user friendly simulation framework for screening and optimizing chemical/microbial enhanced oil recovery processes. The framework will include (1) a user friendly interface to identify the variables that have the most impact on oil recovery using the concept of experimental design and response surface maps, (2) UTCHEM reservoir simulator to perform the numerical simulations, and (3) an economic model that automatically imports the simulation production data to evaluate the profitability of a particular design. Such a reservoir simulation framework is not currently available to the oil industry. The objectives of Task 1 are to develop three primary modules representing reservoir, chemical, and well data. The modules will be interfaced with an already available experimental design model. The objective of the Task 2 is to incorporate UTCHEM reservoir simulator and the modules with the strategic variables and developing the response surface maps to identify the significant variables from each module. The objective of the Task 3 is to develop the economic model designed specifically for the chemical processes targeted in this proposal and interface the economic model with UTCHEM production output. Task 4 is on the validation of the framework and performing simulations of oil reservoirs to screen, design and optimize the chemical processes.

  20. A FRAMEWORK TO DESIGN AND OPTIMIZE CHEMICAL FLOODING PROCESSES

    Energy Technology Data Exchange (ETDEWEB)

    Mojdeh Delshad; Gary A. Pope; Kamy Sepehrnoori

    2005-07-01

    The goal of this proposed research is to provide an efficient and user friendly simulation framework for screening and optimizing chemical/microbial enhanced oil recovery processes. The framework will include (1) a user friendly interface to identify the variables that have the most impact on oil recovery using the concept of experimental design and response surface maps, (2) UTCHEM reservoir simulator to perform the numerical simulations, and (3) an economic model that automatically imports the simulation production data to evaluate the profitability of a particular design. Such a reservoir simulation framework is not currently available to the oil industry. The objectives of Task 1 are to develop three primary modules representing reservoir, chemical, and well data. The modules will be interfaced with an already available experimental design model. The objective of the Task 2 is to incorporate UTCHEM reservoir simulator and the modules with the strategic variables and developing the response surface maps to identify the significant variables from each module. The objective of the Task 3 is to develop the economic model designed specifically for the chemical processes targeted in this proposal and interface the economic model with UTCHEM production output. Task 4 is on the validation of the framework and performing simulations of oil reservoirs to screen, design and optimize the chemical processes.

  1. Floods and Flash Flooding

    Science.gov (United States)

    Floods and flash flooding Now is the time to determine your area’s flood risk. If you are not sure whether you ... If you are in a floodplain, consider buying flood insurance. Do not drive around barricades. If your ...

  2. Use of polymers and a surfactant in the treatment of Kraft process wastewater

    OpenAIRE

    Seyffert, Hans J.

    1988-01-01

    This study-investigated the use of cationic polymers, and a surfactant, EHDABr, in the color removal treatment of Kraft pulp and paper wastewater. Four polymers were evaluated for their color removal performance by jar test procedures. The polymers removed between 77 and 87% of the wastewater color. The affect of pH upon polymer performance varied with the polymer tested. Powdered activated carbon addition improved the performance of the polymers. The color removal abili...

  3. A pore scale investigation of crude oil distribution and removal from homogeneous porous media during surfactant-induced remediation.

    Science.gov (United States)

    Ghosh, Jaydeep; Tick, Geoffrey R

    2013-12-01

    A pore-scale study was conducted to understand interfacial processes contributing to the removal of crude oils from a homogeneous porous medium during surfactant-induced remediation. Synchrotron X-ray microtomography (SXM) was used to obtain high-resolution three-dimensional images of the two-fluid-phase oil/water system, and quantify temporal changes in oil blob distribution, blob morphology, and blob surface area before and after sequential surfactant flooding events. The reduction of interfacial tension in conjunction with the sufficient increase in viscous forces as a result of surfactant flushing was most likely responsible for mobilization and recovery of the two lighter oil fractions. However, corresponding increases in viscous forces as a result of a reduction of interfacial tension were insufficient to initiate and maintain the displacement (recovery) of the heavy crude oil fraction during surfactant flushing. In contrast to the heavy oil system, changes in trapping number for the lighter fraction crude oils were sufficient to initiate mobilization as a result of surfactant flushing. Both light and medium oil fractions showed an increase in the number of blobs and total blob surface area, and a reduction in the total volume after 2 pore volumes (PVs) of surfactant flooding. This increase in surface area was attributed to the change in blob morphology from spherical to more complex non-spherical ganglia shape characteristics. Moreover, the increase in the number of oil blobs from larger to smaller particles after surfactant flushing may have contributed to the greater cumulative oil surface area. Complete recovery of light and medium oil fractions resulted after 5 PVs of surfactant flooding, whereas the displacement efficiency of heavy-oil fraction was severely limited, even after extended periods of flushing. The results of these experiments demonstrate the utility of SXM for quantifying pore-scale interfacial characteristics for specific crude

  4. Physicochemical Properties and Oil Displacement Efficiency of Gemini Surfactant ASP Flooding%Gemini型表面活性剂三元复合体系性能和驱油效果

    Institute of Scientific and Technical Information of China (English)

    范海明; 孟祥灿; 郁登朗; 杨丹丹; 康万利; 徐海

    2014-01-01

    以胱氨酸钠和油酰氯为原料,通过一步反应合成了一种新型阴离子Gemini表面活性剂二油酰胺基胱氨酸钠(Sodium dioleoylamino cystine ,SDOLC),利用 Texas-500C型界面张力仪和MCR301流变仪研究了Gemini型表面活性剂/HPAM/碱三元复合体系降低油水界面张力性能和黏弹性能,在均质和非均质岩心中评价了体系的驱油效果。结果表明,HPAM 的加入不影响Gemini表面活性剂和碱复合溶液与原油界面张力最低值,但可以有效增加体系的黏度。综合考虑界面张力和黏弹性能,选择黏度44 mPa·s且与大庆原油界面张力最低值2.4×10-2 mN/m的含质量分数为0.18% HPAM、0.1% SDOLC、0.15% NaOH和0.06% HEDP · Na4体系作为Gemini型表面活性剂三元复合驱油体系。注入0.6 PV该体系在均质岩心中水驱基础上可提高采收率26.11%,在非均质岩心中水驱基础上可提高采收率22.25%。%The anionic Gemini surfactant Sodium dioleoylamino cystine (SDOLC) was synthesized by one-step reaction of sodium cystine and oleoyl chloride .The reducing oil/water interfacial tension properties and viscoelastic properties of Gemini/HPAM/alkali mixed system were investigated by Texas-500C spinning drop interface tensiometer and MCR301 rheometer ,and the oil displacement efficiency in homogeneous and heterogeneous cores were evaluated . It was found that the minimum dynamic interfacial tension magnitude between Daqing crude oil and Gemini surfactant/alkali mixed solution is not affected with the addition of HPAM ,but the viscosities increased .Overall considering the interfacial tension and viscosity ,mixed solution including mass fraction of 0 .18% HPAM ,0 .1% SDOLC ,0 .15% NaOH and 0 .06% HEDP · Na4 was chose as Gemini surfactant ASP flooding system .The viscosity of this system was 44 mPa · s and oil/water interfacial tension was 2 .4 × 10-2 mN/m .Homogeneous and heterogeneous cores were water

  5. Process controls on regional flood frequency: Coefficient of variation and basin scale

    Science.gov (United States)

    BlöSchl, Günter; Sivapalan, Murugesu

    1997-12-01

    The coefficient of variation (CV) of maximum annual floods is examined to understand the effects of process controls and catchment size. A derived flood frequency model is used to interpret data from 489 catchments in Austria. At the core of process controls appears to be the interaction of catchment response time and storm duration, but the magnitude is not large, and often this interaction is hidden by other processes. The dependence of rainfall intensity and duration is clearly very important and reduces CV significantly. Increasing channel travel times with catchment scale tend to translate into decreasing CVs with area for small catchments while they tend to translate into increasing CVs with area for larger catchments. Nonlinear runoff processes, including threshold effects, is the main mechanism for increasing CV. They give rise to complex patterns in the relationship between CV and area. Base flow has been used as a surrogate for a number of processes, such as seasonality of streamflow. It always decreases CV and, in particular, leads to a significant decrease of CV with area. Both the observed tendency of CV to decrease with area and the scatter in the data are the result of a complex interplay of a number of processes which allows various alternative interpretations. Depending on which processes dominate under a particular hydrologic regime, different patterns arise. It appears that the explanations of the relationship between CV and catchment scale suggested in the literature are too simplistic. The case is made for using the concept of hydrologic regimes and process studies of the type presented here to help delineate homogeneous regions for regional flood frequency analyses in a physically consistent way.

  6. Influence of seismic processes and volcanic activity on the formation of disastrous floods

    Science.gov (United States)

    Trifonov, Dmitriy

    2014-05-01

    Traditionally, the main cause of catastrophic floods are considered prolonged heavy rains, which lead to over-saturation of soil moisture and the deposition of precipitation on the surface of the earth. And at the same time there is reason to believe that precipitation cannot be the main cause of floods. Firstly, we observe a catastrophic floods not in every case of heavy precipitation: moreover, a direct correlation between precipitation intensity and scale of the flooding is not detected. Secondly, a simple calculation shows that the quantity of water, that drops down to the ground with torrential rains, are insufficient to cover the earth's surface such layer of water, where we can talk about the flood (especially catastrophic). In particular, the intensity of normal not tropical rainfall does not exceed 60 mm per hour. Then such a downpour would have to go continuously for at least two days in a row, to cause flooding of a height of 3 m provided a complete impenetrability of the earth's surface. In reality, however, such showers last no more than half an hour. Thus, it can be argued that the source of water for catastrophic floods fed by ground water, the volume of which is comparable with the volume of all surface water on Earth [1]. Classic examples of surface and groundwater interactions are, on the one hand, springs and artesian wells, and on the other hand, the phenomenon of absorption of precipitation by soil. In normal conditions underground water is moving by aquifers, penetrating through the pores and cracks in rocks in the conditions of nonstationary/unsteady filtration, forming a 3D network of underground channels in different directions (horizontal, vertical, inclined), including the so-called underground lakes - water basins in underground cavities. Especially strongly these processes are shown in the fractured and karst rocks. It is also important that the movement of water obeys the laws of hydrostatics and hydrodynamics in terms of specific

  7. Unmanned Aerial Vehicle Systems for Remote Estimation of Flooded Areas Based on Complex Image Processing.

    Science.gov (United States)

    Popescu, Dan; Ichim, Loretta; Stoican, Florin

    2017-02-23

    Floods are natural disasters which cause the most economic damage at the global level. Therefore, flood monitoring and damage estimation are very important for the population, authorities and insurance companies. The paper proposes an original solution, based on a hybrid network and complex image processing, to this problem. As first novelty, a multilevel system, with two components, terrestrial and aerial, was proposed and designed by the authors as support for image acquisition from a delimited region. The terrestrial component contains a Ground Control Station, as a coordinator at distance, which communicates via the internet with more Ground Data Terminals, as a fixed nodes network for data acquisition and communication. The aerial component contains mobile nodes-fixed wing type UAVs. In order to evaluate flood damage, two tasks must be accomplished by the network: area coverage and image processing. The second novelty of the paper consists of texture analysis in a deep neural network, taking into account new criteria for feature selection and patch classification. Color and spatial information extracted from chromatic co-occurrence matrix and mass fractal dimension were used as well. Finally, the experimental results in a real mission demonstrate the validity of the proposed methodologies and the performances of the algorithms.

  8. Unmanned Aerial Vehicle Systems for Remote Estimation of Flooded Areas Based on Complex Image Processing

    Directory of Open Access Journals (Sweden)

    Dan Popescu

    2017-02-01

    Full Text Available Floods are natural disasters which cause the most economic damage at the global level. Therefore, flood monitoring and damage estimation are very important for the population, authorities and insurance companies. The paper proposes an original solution, based on a hybrid network and complex image processing, to this problem. As first novelty, a multilevel system, with two components, terrestrial and aerial, was proposed and designed by the authors as support for image acquisition from a delimited region. The terrestrial component contains a Ground Control Station, as a coordinator at distance, which communicates via the internet with more Ground Data Terminals, as a fixed nodes network for data acquisition and communication. The aerial component contains mobile nodes—fixed wing type UAVs. In order to evaluate flood damage, two tasks must be accomplished by the network: area coverage and image processing. The second novelty of the paper consists of texture analysis in a deep neural network, taking into account new criteria for feature selection and patch classification. Color and spatial information extracted from chromatic co-occurrence matrix and mass fractal dimension were used as well. Finally, the experimental results in a real mission demonstrate the validity of the proposed methodologies and the performances of the algorithms.

  9. A review of atmospheric and land surface processes with emphasis on flood generation in the Southern Himalayan rivers.

    Science.gov (United States)

    Dimri, A P; Thayyen, R J; Kibler, K; Stanton, A; Jain, S K; Tullos, D; Singh, V P

    2016-06-15

    Floods in the southern rim of the Indian Himalayas are a major cause of loss of life, property, crops, infrastructure, etc. They have long term socio-economic impacts on the habitat living along/across the Himalayas. In the recent decade extreme precipitation events have led to numerous flash floods in and around the Himalayan region. Sporadic case-based studies have tried to explain the mechanisms causing the floods. However, in some of the cases, the causative mechanisms have been elusive. Various types of flood events have been debated at different spatial and temporal scales. The present study provides an overview of mechanisms that lead to floods in and around the southern rim of the Indian Himalayas. Atmospheric processes, landuse interaction, and glacier-related outbreaks are considered in the overview.

  10. Spatial Analysis in Determination Of Flood Prone Areas Using Geographic Information System and Analytical Hierarchy Process at Sungai Sembrong's Catchment

    Science.gov (United States)

    Bukari, S. M.; Ahmad, M. A.; Wai, T. L.; Kaamin, M.; Alimin, N.

    2016-07-01

    Floods that struck Johor state in 2006 and 2007 and the East Coastal in 2014 have triggered a greatly impact to the flood management here in Malaysia. Accordingly, this study conducted to determine potential areas of flooding, especially in Batu Pahat district since it faces terrifying experienced with heavy flood. This objective is archived by using the application of Geographic Information Systems (GIS) on study area of flood risk location at the watershed area of Sungai Sembrong. GIS functions as spatial analysis is capable to produce new information based on analysis of data stored in the system. Meanwhile the Analytical Hierarchy Process (AHP) was used as a method for setting up in decision making concerning the existing data. By using AHP method, preparation and position of the criteria and parameters required in GIS are neater and easier to analyze. Through this study, a flood prone area in the watershed of Sungai Sembrong was identified with the help of GIS and AHP. Analysis was conducted to test two different cell sizes, which are 30 and 5. The analysis of flood prone areas were tested on both cell sizes with two different water levels and the results of the analysis were displayed by GIS. Therefore, the use of AHP and GIS are effective and able to determine the potential flood plain areas in the watershed area of Sungai Sembrong.

  11. Mineral-Surfactant Interactions for Minimum Reagents Precipitation and Adsorption for Improved Oil Recovery

    Energy Technology Data Exchange (ETDEWEB)

    P. Somasundaran

    2008-09-20

    /conformation of the adsorbed layers), as well as precipitation/abstraction characteristics. (3) Investigation of the role of dissolved species, especially multivalent ions, on interactions between reservoir minerals and surfactants and/or polymers leading to surfactant precipitation or activated adsorption. (4) Solution behavior tests--surface tension, interaction, ultra filtration, and other tests. (5) Surfactant-mineral interactions relative to adsorption, wettability, and electrophoresis. (6) Work on the effects of multivalent ions, pH, temperature, salinity, and mixing ratio on the adsorption. Developments of adsorption models to explain interactions between surfactants/polymers/minerals. (7) General guidelines for the use of certain surfactants, polymers and their mixtures in micelle flooding processes.

  12. Evaluation of trichloroethene recovery processes in heterogeneous aquifer cells flushed with biodegradable surfactants

    Science.gov (United States)

    Suchomel, Eric J.; Ramsburg, C. Andrew; Pennell, Kurt D.

    2007-12-01

    The ability of two biodegradable surfactants, polyoxyethylene (20) sorbitan monooleate (Tween® 80) and sodium dihexyl sulfosuccinate (Aerosol® MA), to recover a representative dense non-aqueous-phase liquid (DNAPL), trichloroethene (TCE), from heterogeneous porous media was evaluated through a combination of batch and aquifer cell experiments. An aqueous solution containing 3.3% Aerosol MA, 8% 2-propanol and 6 g/l CaCl 2 yielded a weight solubilization ratio (WSR) of 1.21 g TCE/g surfactant, with a corresponding liquid-liquid interfacial tension (IFT) of 0.19 dyn/cm. Flushing of aquifer cells containing a TCE-DNAPL source zone with approximately two pore volumes of the AMA formulation resulted in substantial (> 30%) mobilization of TCE-DNAPL. However, a TCE mass recovery of 81% was achieved when the aqueous-phase flow rate was sufficient to displace the mobile TCE-DNAPL toward the effluent well. Aqueous solutions of Tween 80 exhibited a greater capacity to solubilize TCE (WSR = 1.74 g TCE/g surfactant) and exerted markedly less reduction in IFT (10.4 dyn/cm). These data contradict an accepted empirical correlation used to estimate IFT values from solubilization capacity, and indicate a unique capacity of T80 to form concentrated TCE emulsions. Flushing of aquifer cells with less than 2.5 pore volumes of a 4% T80 solution achieved TCE mass recoveries ranging from 66 to 85%, with only slight TCE-DNAPL mobilization (Tween 80 and Aerosol MA solutions to efficiently recover TCE from a heterogeneous DNAPL source zone, and the utility of the total trapping number as a design parameter for a priori prediction of DNAPL mobilization and bank angle formation when flushing with low-IFT solutions. Given their potential to stimulate microbial reductive dechlorination at low concentrations, these surfactants are well-suited for remedial action plans that couple aggressive mass removal followed by enhanced bioremediation to treat chlorinated solvent source zones.

  13. USING PHASE DIAGRAMS TO PREDICT THE PERFORMANCE OF COSOLVENT FLOODS FOR NAPL REMEDIATION

    Science.gov (United States)

    Cosolvent flooding using water miscible solvents such as alcohols has been proposed as an in-situ NAPL remediation technique. This process is conceptually similar to enhanced oil recovery (EOR) using alcohols and some surfactant formulations. As a result of interest in the EOR ...

  14. Use of naturalized coagulants in removing laundry waste surfactant using various unit processes in lab-scale.

    Science.gov (United States)

    Mohan, S Mariraj

    2014-04-01

    This lab-scale experiment is aimed at demonstrating a treatment system for purification and reuse of laundry rinsing water generated from households. The main objective of the study is to compare the efficiencies of various natural coagulants in removing laundry waste surfactants and other major pollutants from the laundry rinsing water. The treatment system consists of Coagulation-Flocculation, Sand filtration and Granular Activated Carbon (GAC) adsorption. Four experiments were conducted in batch process by varying the coagulants (Nirmali seed and Pectin extracted from pith of Orange peel). Coagulants have been selected due to their local availability at affordable cost and technical feasibility. From the study it is concluded that laundry rinsing water polluted with high turbidity and anionic surfactant treated with Nirmali seeds as coagulant at a retention time of 24 h gives the best results. The treatment system where Orange peel pectin is used as coagulant at a retention time of 24 h is found to be the most efficient one based on the weighted factor. Hence the treatment of laundry rinsing water by aforesaid combination results in better water quality.

  15. Effect of surfactants or a water soluble polymer on the crystal transition of clarithromycin during a wet granulation process.

    Science.gov (United States)

    Nozawa, Kenji; Iwao, Yasunori; Noguchi, Shuji; Itai, Shigeru

    2015-11-10

    To generate products containing a stable form of clarithromycin (CAM) (form II) regardless of the initial crystal form of CAM or type of granulation solvent, the effects of five surfactants, or a water-soluble polymer (macrogol 400) were determined on the crystal transition of CAM. The metastable form (form I) was kneaded with water, after adding surfactants, or a water-soluble polymer. Form II was also kneaded with ethanol, after adding the same additives. The resulting samples were analyzed by powder X-ray diffraction. Form I was completely converted to form II by a wet granulation using water with additives bearing polyoxyethylene chains such as polysorbate 80 (PS80), polyoxyl 40 stearate or macrogol 400. The granulation of the form II using ethanol with these additives did not result in a crystal transition to form I. Furthermore, CAM tablets were manufactured using granules with PS80, and these crystal forms and dissolution behaviors were investigated. As a result, the wet granulation of CAM with PS80 gave CAM tablets containing only form II and PS80 did not have any adverse effects on tablet characteristics. Therefore, these data suggests that the crystal form of CAM can be controlled to be form II using a wet granulation process with additives bearing polyoxyethylene chains regardless of the initial crystal form of CAM or type of granulation solvent. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Risk assessment of urban flood disaster in Jingdezhen City based on analytic hierarchy process and geographic information system

    Science.gov (United States)

    Sun, D. C.; Huang, J.; Wang, H. M.; Wang, Z. Q.; Wang, W. Q.

    2017-08-01

    The research of urban flood risk assessment and management are of great academic and practical importance, which has become a widespread concern throughout the world. It’s significant to understand the spatial-temporal distribution of the flood risk before making the risk response measures. In this study, the urban region of Jingdezhen City is selected as the study area. The assessment indicators are selected from four aspects: disaster-causing factors, disaster-pregnant environment, disaster-bearing body and the prevention and mitigation ability, by consideration of the formation process of urban flood risk. And then, a small-scale flood disaster risk assessment model is developed based on Analytic Hierarchy Process(AHP) and Geographic Information System(GIS), and the spatial-temporal distribution of flood risk in Jingdezhen City is analysed. The results show that the risk decreases gradually from the centre line of Changjiang River to the surrounding, and the areas of high flood disaster risk is decreasing from 2010 to 2013 while the risk areas are more concentred. The flood risk of the areas along the Changjiang River is the largest, followed by the low-lying areas in Changjiang District. And the risk is also large in Zhushan District where the population, the industries and commerce are concentrated. The flood risk in the western part of Changjiang District and the north-eastern part of the study area is relatively low. The results can provide scientific support for flood control construction and land development planning in Jingdezhen City.

  17. Stabilization of {alpha}-amylase by using anionic surfactant during the immobilization process

    Energy Technology Data Exchange (ETDEWEB)

    El-Batal, A.I. [National Center for Radiation Research and Technology, P.O. Box 29, Nasr City, Cairo (Egypt); Atia, K.S. [Nuclear Research Center, Radioisotopes Applications Division, Abo-Zable, P.O. Box 13759, Cairo (Egypt)]. E-mail: ks_atia@yahoo.com; Eid, M. [National Center for Radiation Research and Technology, P.O. Box 29, Nasr City, Cairo (Egypt)

    2005-10-01

    This work describes the entrapment of {alpha}-amylase into butylacrylate-acrylic acid copolymer (BuA/AAc) using {gamma} irradiation. The effect of an anionic surfactant (AOT), the reuse efficiency, and kinetic behavior of immobilized {alpha}-amylase were studied. Covering of {alpha}-amylase with bis-(2-ethylhexyl)sulfosuccinate sodium salt (AOT) made the enzyme more stable than the uncovered form. The hydrolytic activity of the pre-coated immobilized {alpha}-amylase was increased below the critical micelle concentration (cmc) (10mmol/L). The results showed an increase in the relative activity with increase in the degree of hydration. The pre-coated immobilized {alpha}-amylase showed a higher k{sub cat}/K{sub m} and lower activation energy compared to the free and uncoated-immobilized preparation, respectively. The results suggest that the immobilization of {alpha}-amylase is a potentially useful approach for commercial starch hydrolysis in two-phase systems.

  18. Stabilization of α-amylase by using anionic surfactant during the immobilization process

    Science.gov (United States)

    El-Batal, A. I.; Atia, K. S.; Eid, M.

    2005-10-01

    This work describes the entrapment of α-amylase into butylacrylate-acrylic acid copolymer (BuA/AAc) using γ irradiation. The effect of an anionic surfactant (AOT), the reuse efficiency, and kinetic behavior of immobilized α-amylase were studied. Covering of α-amylase with bis-(2-ethylhexyl)sulfosuccinate sodium salt (AOT) made the enzyme more stable than the uncovered form. The hydrolytic activity of the pre-coated immobilized α-amylase was increased below the critical micelle concentration (cmc) (10 mmol/L). The results showed an increase in the relative activity with increase in the degree of hydration. The pre-coated immobilized α-amylase showed a higher k/K and lower activation energy compared to the free and uncoated-immobilized preparation, respectively. The results suggest that the immobilization of α-amylase is a potentially useful approach for commercial starch hydrolysis in two-phase systems.

  19. Development processes of a master plan for flood protection and mitigation in a community area: A case study of Roi Et province

    Directory of Open Access Journals (Sweden)

    Chatchai Jothityangkoon

    2015-12-01

    Full Text Available Development processes of a master plan formulation for flood protection and mitigation consists of the selection process of a targeted area based on risk level, developing a present and future flood inundation map and a flood risk map and identify direction and drainage capacity of the targeted area. Main causes of flooding in the area can be identified leading to designing flood protection and a flood drainage system in both structural and non-structural measures, prior to a public hearing process from stakeholders to finalize the master plan to provide maximum benefits and less negative impact. These processes are applied to Roi Et Province. Based on flood risk criteria, 24 municipalities with high risk are selected. The cause of flooding in the municipality area can be combined in 2 groups, flooding from low efficiency of storm drainage capacity and flooding from overbank flow from the Mun, Chi and Yang Rivers. Structural measures for the first and second group are the improvement of the existing system or changing a new drainage system and the improvement of existing river dikes and levees. It is also possible to design and construct a new one. Constructing a polder system for the community area, requires a budget about 3,338 million baht. To support structural measures, non-structural measures are required, for example, a flood warning system, an emergency response plan during flood disaster.

  20. Flood hazards analysis based on changes of hydrodynamic processes in fluvial systems of Sao Paulo, Brazil.

    Science.gov (United States)

    Simas, Iury; Rodrigues, Cleide

    2016-04-01

    The metropolis of Sao Paulo, with its 7940 Km² and over 20 million inhabitants, is increasingly being consolidated with disregard for the dynamics of its fluvial systems and natural limitations imposed by fluvial terraces, floodplains and slopes. Events such as floods and flash floods became particularly persistent mainly in socially and environmentally vulnerable areas. The Aricanduva River basin was selected as the ideal area for the development of the flood hazard analysis since it presents the main geological and geomorphological features found in the urban site. According to studies carried out by Anthropic Geomorphology approach in São Paulo, to study this phenomenon is necessary to take into account the original hydromorphological systems and its functional conditions, as well as in which dimensions the Anthropic factor changes the balance between the main variables of surface processes. Considering those principles, an alternative model of geographical data was proposed and enabled to identify the role of different driving forces in terms of spatial conditioning of certain flood events. Spatial relationships between different variables, such as anthropogenic and original morphology, were analyzed for that purpose in addition to climate data. The surface hydrodynamic tendency spatial model conceived for this study takes as key variables: 1- The land use present at the observed date combined with the predominant lithological group, represented by a value ranging 0-100, based on indexes of the National Soil Conservation Service (NSCS-USA) and the Hydraulic Technology Center Foundation (FCTH-Brazil) to determine the resulting balance of runoff/infiltration. 2- The original slope, applying thresholds from which it's possible to determine greater tendency for runoff (in percents). 3- The minimal features of relief, combining the curvature of surface in plant and profile. Those three key variables were combined in a Geographic Information System in a series of

  1. Scaling-up parameters for site restoration process using surfactant-enhanced soil washing coupled with wastewater treatment by Fenton and Fenton-like processes.

    Science.gov (United States)

    Bandala, Erick R; Cossio, Horacio; Sánchez-Lopez, Adriana D; Córdova, Felipe; Peralta-Herández, Juan M; Torres, Luis G

    2013-01-01

    Estimation of scaling-up parameters for a site restoration process using a surfactant-enhanced soil washing (SESW) process followed by the application of advanced oxidation processes (Fenton and photo-Fenton) was performed. For the SESW, different parameters were varied and the soil washing efficiency for pesticide (2,4-D) removal assessed. The resulting wastewater was treated using the Fenton reaction in the absence and presence of ultraviolet (UV) radiation for pesticide removal. Results showed that agitation speed of 1550 rpm was preferable for the best pesticide removal from contaminated soil. It was possible to wash contaminated soils with different soil concentrations; however the power drawn was higher as the soil concentration increased. Complete removal of the pesticide and the remaining surfactant was achieved using different reaction conditions. The best degradation conditions were for the photo-Fenton process using [Fe(II)] = 0.3 mM; [H2O2] = 4.0 mM where complete 2,4-D and sodium dodecylsulfate (SDS) removal was observed after 8 and 10 minutes of reaction, respectively. Further increase in the hydrogen peroxide or iron salt concentration did not show any improvement in the reaction rate. Kinetic parameters, i.e. reaction rate constant and scaling-up parameters, were determined. It was shown that, by coupling both processes (SESW and AOPs), it is possible the restoration of contaminated sites.

  2. PROCESSING BIG REMOTE SENSING DATA FOR FAST FLOOD DETECTION IN A DISTRIBUTED COMPUTING ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    A. Olasz

    2017-07-01

    Full Text Available The Earth observation (EO missions of the space agencies and space industry (ESA, NASA, national and commercial companies are evolving as never before. These missions aim to develop and launch next-generation series of satellites and sensors and often provide huge amounts of data, even free of charge, to enable novel monitoring services. The wide geospatial sector is targeted to handle new challenges to store, process and visualize these geospatial data, reaching the level of Big Data by their volume, variety, velocity, along with the need of multi-source spatio-temporal geospatial data processing. Handling and analysis of remote sensing data has always been a cumbersome task due to the ever-increasing size and frequency of collected information. This paper presents the achievements of the IQmulus EU FP7 research and development project with respect to processing and analysis of geospatial big data in the context of flood and waterlogging detection.

  3. Processing Big Remote Sensing Data for Fast Flood Detection in a Distributed Computing Environment

    Science.gov (United States)

    Olasz, A.; Kristóf, D.; Nguyen Thai, B.; Belényesi, M.; Giachetta, R.

    2017-07-01

    The Earth observation (EO) missions of the space agencies and space industry (ESA, NASA, national and commercial companies) are evolving as never before. These missions aim to develop and launch next-generation series of satellites and sensors and often provide huge amounts of data, even free of charge, to enable novel monitoring services. The wide geospatial sector is targeted to handle new challenges to store, process and visualize these geospatial data, reaching the level of Big Data by their volume, variety, velocity, along with the need of multi-source spatio-temporal geospatial data processing. Handling and analysis of remote sensing data has always been a cumbersome task due to the ever-increasing size and frequency of collected information. This paper presents the achievements of the IQmulus EU FP7 research and development project with respect to processing and analysis of geospatial big data in the context of flood and waterlogging detection.

  4. A Methodology for Processing Raw LIDAR Data to Support Urban Flood Modelling Framework

    NARCIS (Netherlands)

    Abdullah, A.F.B.

    2012-01-01

    In the last few decades, the consequences of floods and flash floods in many parts of the world have been devastating. One way of improving flood management practice is to invest in data collection and modelling activities which enable an understanding of the functioning of a system and the selectio

  5. Switchable Surfactants

    National Research Council Canada - National Science Library

    Yingxin Liu; Philip G. Jessop; Michael Cunningham; Charles A. Eckert; Charles L. Liotta

    2006-01-01

    .... We report that long-chain alkyl amidine compounds can be reversibly transformed into charged surfactants by exposure to an atmosphere of carbon dioxide, thereby stabilizing water/alkane emulsions...

  6. Characterization of process-oriented hydrologic model behavior with temporal sensitivity analysis for flash floods in Mediterranean catchments

    Directory of Open Access Journals (Sweden)

    P. A. Garambois

    2013-06-01

    Full Text Available This paper presents a detailed analysis of 10 flash flood events in the Mediterranean region using the distributed hydrological model MARINE. Characterizing catchment response during flash flood events may provide new and valuable insight into the dynamics involved for extreme catchment response and their dependency on physiographic properties and flood severity. The main objective of this study is to analyze flash-flood-dedicated hydrologic model sensitivity with a new approach in hydrology, allowing model outputs variance decomposition for temporal patterns of parameter sensitivity analysis. Such approaches enable ranking of uncertainty sources for nonlinear and nonmonotonic mappings with a low computational cost. Hydrologic model and sensitivity analysis are used as learning tools on a large flash flood dataset. With Nash performances above 0.73 on average for this extended set of 10 validation events, the five sensitive parameters of MARINE process-oriented distributed model are analyzed. This contribution shows that soil depth explains more than 80% of model output variance when most hydrographs are peaking. Moreover, the lateral subsurface transfer is responsible for 80% of model variance for some catchment-flood events' hydrographs during slow-declining limbs. The unexplained variance of model output representing interactions between parameters reveals to be very low during modeled flood peaks and informs that model-parsimonious parameterization is appropriate to tackle the problem of flash floods. Interactions observed after model initialization or rainfall intensity peaks incite to improve water partition representation between flow components and initialization itself. This paper gives a practical framework for application of this method to other models, landscapes and climatic conditions, potentially helping to improve processes understanding and representation.

  7. Surfactant-free coating of thiols on gold nanoparticles using sonochemistry: a study of competing processes.

    Science.gov (United States)

    Pallipurath, Anuradha; Nicoletti, Olivia; Skelton, Jonathan M; Mahajan, Sumeet; Midgley, Paul A; Elliott, Stephen R

    2014-09-01

    A method for the surfactant-free coating of gold nanoparticles with thiols using sonochemistry is presented. The gold nanoparticles were prepared by a modified Zsigmondy method, affording good control over the particle-size distribution, and the thiol coating was performed by the sonication of a biphasic system consisting of a nanoparticle suspension in water and thiols in toluene. The effects of two important reaction parameters on the particle morphology, viz. sonication time and thiol concentration, were investigated in detail using transmission electron microscopy. The effect of the thiol chain length was also studied. We show that the morphology of the coated particles is determined through a competition between two opposing effects: particle fusion, due to the sonication conditions, and digestive ripening, due to the action of the thiols. Additionally, we illustrate the utility of our technique for various applications, including surface-enhanced Raman scattering from bound molecules, and further functionalization using a thiol-exchange reaction. Our technique paves the way for an efficient synthesis of thiol-coated AuNPs of different shapes and sizes, suitable for a range of diverse applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Modeling a glacial lake outburst flood process chain: the case of Lake Palcacocha and Huaraz, Peru

    Science.gov (United States)

    Somos-Valenzuela, Marcelo A.; Chisolm, Rachel E.; Rivas, Denny S.; Portocarrero, Cesar; McKinney, Daene C.

    2016-07-01

    One of the consequences of recent glacier recession in the Cordillera Blanca, Peru, is the risk of glacial lake outburst floods (GLOFs) from lakes that have formed at the base of retreating glaciers. GLOFs are often triggered by avalanches falling into glacial lakes, initiating a chain of processes that may culminate in significant inundation and destruction downstream. This paper presents simulations of all of the processes involved in a potential GLOF originating from Lake Palcacocha, the source of a previously catastrophic GLOF on 13 December 1941, killing about 1800 people in the city of Huaraz, Peru. The chain of processes simulated here includes (1) avalanches above the lake; (2) lake dynamics resulting from the avalanche impact, including wave generation, propagation, and run-up across lakes; (3) terminal moraine overtopping and dynamic moraine erosion simulations to determine the possibility of breaching; (4) flood propagation along downstream valleys; and (5) inundation of populated areas. The results of each process feed into simulations of subsequent processes in the chain, finally resulting in estimates of inundation in the city of Huaraz. The results of the inundation simulations were converted into flood intensity and preliminary hazard maps (based on an intensity-likelihood matrix) that may be useful for city planning and regulation. Three avalanche events with volumes ranging from 0.5 to 3 × 106 m3 were simulated, and two scenarios of 15 and 30 m lake lowering were simulated to assess the potential of mitigating the hazard level in Huaraz. For all three avalanche events, three-dimensional hydrodynamic models show large waves generated in the lake from the impact resulting in overtopping of the damming moraine. Despite very high discharge rates (up to 63.4 × 103 m3 s-1), the erosion from the overtopping wave did not result in failure of the damming moraine when simulated with a hydro-morphodynamic model using excessively conservative soil

  9. Surfactant adsorption kinetics in microfluidics

    Science.gov (United States)

    Riechers, Birte; Maes, Florine; Akoury, Elias; Semin, Benoît; Gruner, Philipp; Baret, Jean-Christophe

    2016-10-01

    Emulsions are metastable dispersions. Their lifetimes are directly related to the dynamics of surfactants. We design a microfluidic method to measure the kinetics of adsorption of surfactants to the droplet interface, a key process involved in foaming, emulsification, and droplet coarsening. The method is based on the pH decay in the droplet as a direct measurement of the adsorption of a carboxylic acid surfactant to the interface. From the kinetic measurement of the bulk equilibration of the pH, we fully determine the adsorption process of the surfactant. The small droplet size and the convection during the droplet flow ensure that the transport of surfactant through the bulk is not limiting the kinetics of adsorption. To validate our measurements, we show that the adsorption process determines the timescale required to stabilize droplets against coalescence, and we show that the interface should be covered at more than 90% to prevent coalescence. We therefore quantitatively link the process of adsorption/desorption, the stabilization of emulsions, and the kinetics of solute partitioning—here through ion exchange—unraveling the timescales governing these processes. Our method can be further generalized to other surfactants, including nonionic surfactants, by making use of fluorophore-surfactant interactions.

  10. Process-Based Modeling of Floods Through Shrub Carrs of Varying Densities

    Science.gov (United States)

    Smith, J.

    2001-12-01

    Floodplain surfaces typically are protected from erosion during deep overbank flows by vegetation of varying types and densities. Drag on stems, branches, leaves, and exposed roots of the floodplain plants reduces both the near-bed flow and the fluid forces on the sediment grains. The drag on vegetation and on topographic elements of the floodplain surface can be calculated by carefully applying fundamental fluid-mechanical principals. Doing so requires identification and appropriate approximation of the reference velocity in the drag equation, and accurate estimates of the floodplain plant geometries and spacings. For shrubs, calculations indicate that skin friction on leaves is negligible compared to form drag on stems and branches, whereas, for uncut grasses, skin friction on the fronds is of primary importance. Scaling relationships are developed for each shrub species for specific applications, so that the fluid mechanically important properties can be estimated from mean stem diameters, mean stem group diameters, and mean stem group spacings. Stem group spacings and diameters can be related to shrub-canopy spacings and diameters respectively, which are determined from aerial photographs in the applications. A process-based model incorporating the necessary principles was developed and applied to a headwater tributary of East Plum Creek, Colorado. Calculations using the estimated decrease in density of the sandbar willows along this tributary accurately postdict the site of initiation of floodplain unraveling (transformation from a narrow, sinuous stream to a wide, straight one) that occurred during an extreme flood in 1965. Details of this application are presented in an accompanying poster. The model then is applied to Clark Fork of the Columbia River in the Deer Lodge Valley, Montana. This meandering fluvial system is an EPA Superfund site, because the flood-of-record in 1908 deposited several decimeters of contaminated tailings in the meander belt. The

  11. ADSORPTION OF SURFACTANT ON CLAYS

    Science.gov (United States)

    Surfactants used to enhance remediation of soils by soil washing are often lost in the process. Neither the amount nor the cause of this loss is known. It is assumed that clays present in the soil are responsible for the loss of the surfactant. In this papere, adsorption prope...

  12. Examining the Roles of Emulsion Droplet Size and Surfactant in the Interfacial Instability-Based Fabrication Process of Micellar Nanocrystals

    Science.gov (United States)

    Sun, Yuxiang; Mei, Ling; Han, Ning; Ding, Xinyi; Yu, Caihao; Yang, Wenjuan; Ruan, Gang

    2017-06-01

    The interfacial instability process is an emerging general method to fabricate nanocrystal-encapsulated micelles (also called micellar nanocrystals) for biological detection, imaging, and therapy. The present work utilized fluorescent semiconductor nanocrystals (quantum dots or QDs) as the model nanocrystals to investigate the interfacial instability-based fabrication process of nanocrystal-encapsulated micelles. Our experimental results suggest intricate and intertwined roles of the emulsion droplet size and the surfactant poly (vinyl alcohol) (PVA) used in the fabrication process of QD-encapsulated poly (styrene-b-ethylene glycol) (PS-PEG) micelles. When no PVA is used, no emulsion droplet and thus no micelle is successfully formed; Emulsion droplets with large sizes ( 25 μm) result in two types of QD-encapsulated micelles, one of which is colloidally stable QD-encapsulated PS-PEG micelles while the other of which is colloidally unstable QD-encapsulated PVA micelles; In contrast, emulsion droplets with small sizes ( 3 μm or smaller) result in only colloidally stable QD-encapsulated PS-PEG micelles. The results obtained in this work not only help to optimize the quality of nanocrystal-encapsulated micelles prepared by the interfacial instability method for biological applications but also offer helpful new knowledge on the interfacial instability process in particular and self-assembly in general.

  13. Selective oxidative degradation of toluene for the recovery of surfactant by an electro/Fe²⁺/persulfate process.

    Science.gov (United States)

    Long, Anhua; Zhang, Hui

    2015-08-01

    An electro/Fe(2+)/persulfate process has been conducted for toluene removal from surfactant (SDS) flushing solution, and the pseudo-second-order reaction rate constant (k2 value) of toluene removal has been optimized by a response surface methodology (RSM). The results indicated that in this process, the reaction between persulfate and externally added Fe(2+) generates sulfate-free radicals, and at the same time, Fe(2+) is electro-regenerated at the cathode by the reduction of Fe(3+). RSM based on Box-Behnken design (BBD) has been applied to analyze the experimental variables, of which the concentrations of persulfate and Fe(2+) showed a positive effect on the rate constant of toluene removal, whereas the concentration of SDS showed a negative effect. The interactions between pairs of variables proved to be significant, such as between SDS, persulfate, and Fe(2+) concentrations. ANOVA results confirmed that the proposed models were accurate and reliable for analysis of the variables of the electro/Fe(2+)/persulfate process. The shapes of the 3D response surfaces and contour plots showed that the SDS, persulfate, and Fe(2+) concentrations substantially affected the k2 value of toluene removal. The results indicated that increasing persulfate or Fe(2+) concentration increased the k2 value, whereas increasing SDS concentration decreased the k2 value. The reaction intermediates have been identified by GC-MS, and a plausible degradation pathway for toluene degradation is proposed.

  14. Towards a robust assessment of bridge clogging processes in flood risk management

    Science.gov (United States)

    Gschnitzer, T.; Gems, B.; Mazzorana, B.; Aufleger, M.

    2017-02-01

    River managers are aware that wood-clogging mechanisms frequently trigger damage-causing processes like structural damages at bridges, sudden channel outbursts, and occasionally, major displacements of the water course. To successfully mitigate flood risks related to the transport of large wood (LW), river managers need a guideline for an accurate and reliable risk assessment procedure and the design of river sections and bridges that are endangered of LW clogging. In recent years, comprehensive research dealing with the triggers of wood-clogging mechanisms at bridges and the corresponding impacts on flood risk was accomplished at the University of Innsbruck. A large set of laboratory experiments in a rectangular flume was conducted. In this paper we provide an overall view of these tests and present our findings. By applying a logistic regression analysis, the available knowledge on the influence of geometrical, hydraulic, and wood-related parameters on LW clogging probabilities is processed in a generalized form. Based on the experimental modeling results a practice-oriented guideline that supports the assessment of flood risk induced by LW clogging, is presented. In this context, two specific local structural protection measures at the bridge, aiming for a significant decrease of the entrapment probabilities, are illustrated: (i) a deflecting baffle installed on the upstream face of the bridge and (ii) a channel constriction leading to a change in flow state and a corresponding increase of the flow velocities and the freeboard at the bridge cross section. The presented guideline is based on a three-step approach: estimation of LW potential, entrainment, and transport; clogging scenario at the bridge; and the impact on channel and floodplain hydraulics. For a specific bridge susceptible to potential clogging caused by LW entrapment, it allows for a qualitative evaluation of potential LW entrainment in the upstream river segments, its transport toward the

  15. A new automatic SAR-based flood mapping application hosted on the European Space Agency's grid processing on demand fast access to imagery environment

    Science.gov (United States)

    Hostache, Renaud; Chini, Marco; Matgen, Patrick; Giustarini, Laura

    2013-04-01

    There is a clear need for developing innovative processing chains based on earth observation (EO) data to generate products supporting emergency response and flood management at a global scale. Here an automatic flood mapping application is introduced. The latter is currently hosted on the Grid Processing on Demand (G-POD) Fast Access to Imagery (Faire) environment of the European Space Agency. The main objective of the online application is to deliver flooded areas using both recent and historical acquisitions of SAR data in an operational framework. It is worth mentioning that the method can be applied to both medium and high resolution SAR images. The flood mapping application consists of two main blocks: 1) A set of query tools for selecting the "crisis image" and the optimal corresponding pre-flood "reference image" from the G-POD archive. 2) An algorithm for extracting flooded areas using the previously selected "crisis image" and "reference image". The proposed method is a hybrid methodology, which combines histogram thresholding, region growing and change detection as an approach enabling the automatic, objective and reliable flood extent extraction from SAR images. The method is based on the calibration of a statistical distribution of "open water" backscatter values inferred from SAR images of floods. Change detection with respect to a pre-flood reference image helps reducing over-detection of inundated areas. The algorithms are computationally efficient and operate with minimum data requirements, considering as input data a flood image and a reference image. Stakeholders in flood management and service providers are able to log onto the flood mapping application to get support for the retrieval, from the rolling archive, of the most appropriate pre-flood reference image. Potential users will also be able to apply the implemented flood delineation algorithm. Case studies of several recent high magnitude flooding events (e.g. July 2007 Severn River flood

  16. Numerical simulation of pore-scale flow in chemical flooding process

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Chemical flooding is one of the effective technologies to increase oil recovery of petroleum reservoirs after water flooding.Above the scale of representative elementary volume(REV), phenomenological modeling and numerical simulations of chemical flooding have been reported in literatures,but the studies alike are rarely conducted at the pore-scale,at which the effects of physicochemical hydrodynamics are hardly resolved either by experimental observations or by traditional continuum-based simulations.In...

  17. Understanding processes that generate flash floods in the arid Judean Desert to the Dead Sea - a measurement network

    Science.gov (United States)

    Hennig, Hanna; Rödiger, Tino; Laronne, Jonathan B.; Geyer, Stefan; Merz, Ralf

    2016-04-01

    Flash floods in (semi-) arid regions are fascinating in their suddenness and can be harmful for humans, infrastructure, industry and tourism. Generated within minutes, an early warning system is essential. A hydrological model is required to quantify flash floods. Current models to predict flash floods are often based on simplified concepts and/or on concepts which were developed for humid regions. To more closely relate such models to local conditions, processes within catchments where flash floods occur require consideration. In this study we present a monitoring approach to decipher different flash flood generating processes in the ephemeral Wadi Arugot on the western side of the Dead Sea. To understand rainfall input a dense rain gauge network was installed. Locations of rain gauges were chosen based on land use, slope and soil cover. The spatiotemporal variation of rain intensity will also be available from radar backscatter. Level pressure sensors located at the outlet of major tributaries have been deployed to analyze in which part of the catchment water is generated. To identify the importance of soil moisture preconditions, two cosmic ray sensors have been deployed. At the outlet of the Arugot water is sampled and level is monitored. To more accurately determine water discharge, water velocity is measured using portable radar velocimetry. A first analysis of flash flood processes will be presented following the FLEX-Topo concept .(Savenije, 2010), where each landscape type is represented using an individual hydrological model according to the processes within the three hydrological response units: plateau, desert and outlet. References: Savenije, H. H. G.: HESS Opinions "Topography driven conceptual modelling (FLEX-Topo)", Hydrol. Earth Syst. Sci., 14, 2681-2692, doi:10.5194/hess-14-2681-2010, 2010.

  18. Synthesis and Characterization of Flower-Like Bundles of ZnO Nanosheets by a Surfactant-Free Hydrothermal Process

    Directory of Open Access Journals (Sweden)

    Jijun Qiu

    2014-01-01

    Full Text Available Flower-like bundles of ZnO nanosheets have been prepared by using preheating hydrothermal process without any surfactants. The flower-like bundles consist of many thin and uniform hexagonal-structured ZnO nanosheets, with a thickness of 50 nm. The selected area electronic diffraction (SAED and high-resolution transmission electron microscope (HRTEM images indicate that the ZnO nanosheets are single crystal in nature. The growth mechanism of the flower-like bundles of ZnO nanosheets is discussed based on the morphology evolution with growth times and reaction conditions. It is believed that the formation of flower-like bundles of ZnO nanosheets is related to the shielding effect of OH− ions and the self-assembly process, which is dominated by a preheating time. Room temperature photoluminescence spectra results show that the annealing atmosphere strongly affects the visible emission band, which is sensitive to intrinsic and surface defects, especially oxygen interstitials, in flower-like bundles of ZnO nanosheets.

  19. Alkali-Surfactant-Polymer Flooding Wastewater Treatment by Two-Stage Internal Circulation Flotation%两级内循环浮选处理三元复合驱污水

    Institute of Scientific and Technical Information of China (English)

    吴浩; 于忠臣; 王松; 刘扬

    2012-01-01

    Alkali-Surfactant-Polymer flooding wastewater treatment was studied by two-stage internal circulation flotation. Influencing factor of oil-water separation was discussed in detail, such as PAM and surfactant concentration, temperature, air flow rate, pH value and hydraulic retention time. The number of emulsified oil particles change with time was analyzed by Microscopy imaging technology. The result showed that PAM could reduce the effect of surfactant on wastewater characteristic, and improve the efficiency of oil-water separation. Temperature and the initial oil concentration had little effect on oil removal rate, but other factors had significant effect. When the pH value was more than 9. 5, air flow rate of 1. 5-2. 0 m3/h, hydraulic retention time 2. 0 h, the oil removal rate could reach its highest value of 85. 0% or more. Microscopy imaging showed that the oil particle diameter in the wastewater was in the range of 3. 0- 15. 0 μm. The number of oil particles reduced faster in the first one hour of hydraulic retention time than in the second one hour of hydraulic retention time.%利用两级内循环浮选技术处理三元复合驱污水,考察了PAM质量浓度、SDBS质量浓度、污水温度、供气量、pH值和水力停留时间对油-水分离的影响.利用显微镜成像技术分析油粒数量随时间的变化规律.结果表明,PAM的存在能够减小SDBS对油-水分离性能的影响,提高油去除率.三元复合驱污水温度和初始油浓度对油去除率影响较小,而污水pH值、供气量和水力停留时间的影响较大.当pH>9.5、供气量为1.5~2.0 m3/h和水力停留时间2.0h时,三元复合驱污水油去除率较高,达到85%以上.显微镜成像显示,油粒直径在3.0~15.0 μm范围,水力停留时间前1.0h中污水中油粒数量减少较多,而后1.0h中减少缓慢.

  20. Acute toxicity and relationship between metabolites and ecotoxicity during the biodegradation process of non-ionic surfactants: fatty-alcohol ethoxylates, nonylphenol polyethoxylate and alkylpolyglucosides.

    Science.gov (United States)

    Jurado, E; Fernández-Serrano, M; Núñez-Olea, J; Luzón, G; Lechuga, M

    2009-01-01

    The toxicity values of fatty-alcohol ethoxylates, nonylphenol polyethoxylate, and alkylpolyglucosides have been determined by applying assays with luminescent bacteria. Also, the relation between metabolites and ecotoxicity during the biodegradation process has been determined. The biodegradation tests were carried out according to the OECD 301 E test for ready biodegradability. In these tests a solution of the surfactant, representing the sole carbon source for the microorganisms, was tested in a mineral medium, inoculated and incubated under aerobic conditions in the dark. The toxicity of surfactants is related to their molecular structure (Quantitative Structure Activity Relationships, QSAR). For the alkylpolyglucosides, toxicity expressed as EC(50) is related with the critical micelle concentration (CMC), the hydrophilic-lipophilic balance (HLB) of the surfactant, and the hydrophobic alkyl chain (R). The results indicate that toxicity increased as the CMC decreased and as the hydrophobicity increased and R rose. For fatty-alcohol ethoxylates, parameters characteristic studied have been HLB, number of units of ethylene oxide and the alkyl chain length. Relationships found are in agreement with the fact that increasing the alkyl chain length leads to a lower EC(50), whereas increasing ethoxylation leads to a lower toxicity. An analysis of the behaviour of the toxicity and HLB again indicates that the toxicity was greater for surfactants with a smaller HLB. The evolution of the toxicity was studied over the biodegradation process, expressed as a percentage of inhibition. For all the non-ionic surfactants assayed, except for the nonylphenol polyethoxylate, a major decline was found in toxicity during the first days of the biodegradation assay and at all the concentrations tested.

  1. MINERAL-SURFACTANT INTERACTIONS FOR MINIMUM REAGENTS PRECIPITATION AND ADSORPTION FOR IMPROVED OIL RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    P. Somasundaran

    2005-04-30

    solutions and at mineral/solution interfaces were investigated by monitoring micropolarity of the aggregates using fluorescence technique. Compositional changes of the aggregates in solution were observed with the increase in surfactant concentration. The importance of this lies in that the resulting polarity/hydrophobicity change of the mixed micelles will affect the adsorption of surfactant mixtures on reservoir minerals, surfactant/oil emulsion formation and wettability, as a result, the oil release efficiency of the chemical flooding processes in EOR.

  2. Role of rock surface charge in the carbonated water flooding process

    NARCIS (Netherlands)

    Peksa, A.E.; Zitha, P.L.J.; Wolf, K.H.A.A.

    2013-01-01

    Carbonated Water Flooding (CWF) is an alternative EOR method where an oil reservoir is flooded with carbonated (CO2-enriched) water. It is a promising solution for improving oil recovery that benefits from oil viscosity reduction, an increase in oil relative permeability and enhancement of oil

  3. H2O2/UV process for surfactants removal from water

    OpenAIRE

    Melihen, Andrej

    2015-01-01

    Besides conventional approaches to water and wastewater treatment, we know many of advanced processes that are considered as more efficient ways of treatment. Amongst them have an important role, so called, advanced oxidation processes (AOP’s) that generates highly reactive hydroksyl radicals which degrade and remove a wide specter of biologicaly nondegradable pollutants. While operating a source of UV radiation can be used or not. In present study, H2O2/UV-C treatment was appl...

  4. "Physically-based" numerical experiment to determine the dominant hillslope processes during floods?

    Science.gov (United States)

    Gaume, Eric; Esclaffer, Thomas; Dangla, Patrick; Payrastre, Olivier

    2016-04-01

    To study the dynamics of hillslope responses during flood event, a fully coupled "physically-based" model for the combined numerical simulation of surface runoff and underground flows has been developed. A particular attention has been given to the selection of appropriate numerical schemes for the modelling of both processes and of their coupling. Surprisingly, the most difficult question to solve, from a numerical point of view, was not related to the coupling of two processes with contrasted kinetics such as surface and underground flows, but to the high gradient infiltration fronts appearing in soils, source of numerical diffusion, instabilities and sometimes divergence. The model being elaborated, it has been successfully tested against results of high quality experiments conducted on a laboratory sandy slope in the early eighties, which is still considered as a reference hillslope experimental setting (Abdul & Guilham). The model appeared able to accurately simulate the pore pressure distributions observed in this 1.5 meter deep and wide laboratory hillslope, as well as its outflow hydrograph shapes and the measured respective contributions of direct runoff and groundwater to these outflow hydrographs. Based on this great success, the same model has been used to simulate the response of a theoretical 100-meter wide and 10% sloped hillslope, with a 2 meter deep pervious soil and impervious bedrock. Three rain events have been tested: a 100 millimeter rainfall event over 10 days, over 1 day or over one hour. The simulated responses are hydrologically not realistic and especially the fast component of the response, that is generally observed in the real-world and explains flood events, is almost absent of the simulated response. Thinking a little about the whole problem, the simulation results appears totally logical according to the proposed model. The simulated response, in fact a recession hydrograph, corresponds to a piston flow of a relatively uniformly

  5. Pre- and post-processing of hydro-meteorological ensembles for the Norwegian flood forecasting system in 145 basins.

    Science.gov (United States)

    Jahr Hegdahl, Trine; Steinsland, Ingelin; Merete Tallaksen, Lena; Engeland, Kolbjørn

    2016-04-01

    Probabilistic flood forecasting has an added value for decision making. The Norwegian flood forecasting service is based on a flood forecasting model that run for 145 basins. Covering all of Norway the basins differ in both size and hydrological regime. Currently the flood forecasting is based on deterministic meteorological forecasts, and an auto-regressive procedure is used to achieve probabilistic forecasts. An alternative approach is to use meteorological and hydrological ensemble forecasts to quantify the uncertainty in forecasted streamflow. The hydrological ensembles are based on forcing a hydrological model with meteorological ensemble forecasts of precipitation and temperature. However, the ensembles of precipitation are often biased and the spread is too small, especially for the shortest lead times, i.e. they are not calibrated. These properties will, to some extent, propagate to hydrological ensembles, that most likely will be uncalibrated as well. Pre- and post-processing methods are commonly used to obtain calibrated meteorological and hydrological ensembles respectively. Quantitative studies showing the effect of the combined processing of the meteorological (pre-processing) and the hydrological (post-processing) ensembles are however few. The aim of this study is to evaluate the influence of pre- and post-processing on the skill of streamflow predictions, and we will especially investigate if the forecasting skill depends on lead-time, basin size and hydrological regime. This aim is achieved by applying the 51 medium-range ensemble forecast of precipitation and temperature provided by the European Center of Medium-Range Weather Forecast (ECMWF). These ensembles are used as input to the operational Norwegian flood forecasting model, both raw and pre-processed. Precipitation ensembles are calibrated using a zero-adjusted gamma distribution. Temperature ensembles are calibrated using a Gaussian distribution and altitude corrected by a constant gradient

  6. Reducing uncertainty in the selection of bi-variate distributions of flood peaks and volumes using copulas and hydrological process-based model selection

    Science.gov (United States)

    Szolgay, Jan; Gaál, Ladislav; Bacigál, Tomáš; Kohnová, Silvia; Blöschl, Günter

    2016-04-01

    Bi-variate distributions of flood peaks and flood event volumes are needed for a range of practical purposes including e.g. retention basin design and identifying extent and duration of flooding in flood hazard zones. However, the selection of the types of bi-variate distributions and estimating their parameters from observed peak-volume pairs are associated with far larger uncertainties compared to uni-variate distributions, since observed flood records of required length are rarely available. This poses a serious problem to reliable flood risk estimation in bi-variate design cases. The aim of this contribution was to shed light on the possibility of reducing uncertainties in the estimation of the dependence models/parameters from a regional perspective. The peak-volume relationships were modeled in terms of copulas. Flood events were classified according to their origin. In order to reduce the uncertainty in estimating flood risk, pooling and analyzing catchments of similar behavior according to flood process types was attempted. Most of the work reported in the literature so far did not direct the multivariate analysis toward discriminating certain types of models regionally according to specific runoff generation processes. Specifically, the contribution addresses these problems: - Are the peak-volume relationships of different flood types for a given catchment similar? - Are the peak-volume dependence structures between catchments in a larger region for given flood types similar? - Are some copula types more suitable for given flood process types and does this have consequences for reliable risk estimation? The target region is located in the northern parts of Austria, and consists of 72 small and mid-sized catchments. Instead of the traditional approach that deals with annual maximum floods, the current analysis includes all independent flood events in the region. 24 872 flood events from the period 1976-2007 were identified, and classified as synoptic, flash

  7. Fabrication and evaluation of valsartan–polymer–surfactant composite nanoparticles by using the supercritical antisolvent process

    Directory of Open Access Journals (Sweden)

    Kim MS

    2014-11-01

    Full Text Available Min-Soo Kim,1 In-hwan Baek21College of Pharmacy, Pusan National University, Geumjeong-gu, Busan, Republic of Korea; 2College of Pharmacy, Kyungsung University, Daeyeon-dong, Nam-gu, Busan, Republic of KoreaAbstract: The aim of this study was to fabricate valsartan composite nanoparticles by using the supercritical antisolvent (SAS process, and to evaluate the correlation between in vitro dissolution and in vivo pharmacokinetic parameters for the poorly water-soluble drug valsartan. Spherical composite nanoparticles with a mean size smaller than 400 nm, which contained valsartan, were successfully fabricated by using the SAS process. X-ray diffraction and thermal analyses indicated that valsartan was present in an amorphous form within the composite nanoparticles. The in vitro dissolution and oral bioavailability of valsartan were dramatically enhanced by the composite nanoparticles. Valsartan–hydroxypropyl methylcellulose–poloxamer 407 nanoparticles exhibited faster drug release (up to 90% within 10 minutes under all dissolution conditions and higher oral bioavailability than the raw material, with an approximately 7.2-fold higher maximum plasma concentration. In addition, there was a positive linear correlation between the pharmacokinetic parameters and the in vitro dissolution efficiency. Therefore, the preparation of composite nanoparticles with valsartan–hydroxypropyl methylcellulose and poloxamer 407 by using the SAS process could be an effective formulation strategy for the development of a new dosage form of valsartan with high oral bioavailability.Keywords: supersaturation, bioavailability, solid dispersion, dissolution, supercritical fluid

  8. Polyvinyl Alcohol with Superior Flooding Properties to Enhance Oil Recovery Process

    National Research Council Canada - National Science Library

    O. Arjmand; S. Izadi; M. Mousavi; V. Rahmanian

    2012-01-01

    .... Regarding the fact that Hydrolyzed Poly Acryl Amid (HPAM) decomposes in high temperature and pressure conditions, only reservoirs with medium temperature and pressure are suitable for polymer flooding technique...

  9. Scale-up of miscible flood processes for heterogeneous reservoirs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Orr, F.M. Jr.

    1996-04-01

    Results of a wide-ranging investigation of the scaling of gas injection processes are reported. The research examines how the physical mechanisms at work during a gas injection project interact to determine process performance. In particular, the authors examine: the interactions of equilibrium phase behavior and two-phase flow that determine local displacement efficiency and minimum miscibility pressure, the combined effects of viscous fingering, gravity segregation and heterogeneity that control sweep efficiency in 2- and 3-dimensional porous media, the use of streamtube/streamline methods to create very efficient simulation technique for multiphase compositional displacements, the scaling of viscous, capillary and gravity forces for heterogeneous reservoirs, and the effects of the thin films and spreading behavior on three-phase flow. The following key results are documented: rigorous procedures for determination of minimum miscibility pressure (MMP) or minimum miscibility enrichment (MME) for miscibility have been developed for multicomponent systems; the complex dependence of MMP`s for nitrogen/methane floods on oil and injection gas composition observed experimentally is explained for the first time; the presence of layer-like heterogeneities strongly influences the interplay of gravity segregation and viscous fingering, as viscous fingers adapt to preferential flow paths and low permeability layers restrict vertical flow; streamtube/streamline simulation techniques are demonstrated for a variety of injection processes in 2 and 3 dimensions; quantitative scaling estimates for the transitions from capillary-dominated to gravity-dominated to viscous-dominated flows are reported; experimental results are given that demonstrate that high pressure CO{sub 2} can be used to generate low IFT gravity drainage in fractured reservoirs if fractures are suitably connected; and the effect of wetting and spreading behavior on three-phase flow is described. 209 refs.

  10. Deconvolving Flood Plain Dynamical Processes from Pedogenic Processes on Ancient Floodplains

    Science.gov (United States)

    Sheldon, N. D.

    2014-12-01

    Paleosols (fossil soils) preserved in ancient floodplain systems represent one of the most widely used and potentially powerful continental paleoclimatic archives. At the same time, to apply most of the quantitative paleoclimate proxies requires the deconvolution of floodplain dynamics from pedogenic processes. For example, a paleosol could be weakly developed because of low atmospheric CO2 levels, low amounts of precipitation, or because of short formation duration due to frequent channel avulsion. The interpretation of local floodplain dynamics in paleo-floodplain systems is often simplistic, assuming both straightforward uniformitarianism and also that a single vertical section represents that lateral diversity of environments, however, these assumptions have rarely, if ever, been put to the test. Herein, a variety of paleoclimatic and paleobiological proxies will be examined in well-preserved paleo-floodplain settings in Spain, Wyoming, and Montana to test those assumptions. Multi-proxy (phytolith, stable isotope) paleovegetation studies along paleo-floodplain transects in Montana (Miocene, Eocene) indicate substantial heterogeneity at the scale of tens to hundreds of meters, floodplain dynamics-driven succession, and cryptic paludal or everwet areas that are not recognizable purely on the basis of sedimentology. Similarly, rapidly aggrading floodplains in fluvial distributary systems (Spain, Miocene) or in dryland basins (Montana) often record significant mismatches between paleosol-based and paleobotanically based estimates of paleoprecipitation, likely due to variable sediment accumulation rates. Both of those sets of results indicate that single vertical sections are unlikely to represent the breadth floodplain environments and properties operating across paleo-floodplain systems. In contrast, newly described mineralogical proxies based on rock magnetics that can be used to reconstruct paleoclimatic/paleoenvironmental properties appear to be robust at the

  11. Anaerobic Biodegradation of Detergent Surfactants

    Directory of Open Access Journals (Sweden)

    Erich Jelen

    2009-03-01

    Full Text Available Detergent surfactantscan be found in wastewater in relevant concentrations. Most of them are known as ready degradable under aerobic conditions, as required by European legislation. Far fewer surfactants have been tested so far for biodegradability under anaerobic conditions. The natural environment is predominantly aerobic, but there are some environmental compartments such as river sediments, sub-surface soil layer and anaerobic sludge digesters of wastewater treatment plants which have strictly anaerobic conditions. This review gives an overview on anaerobic biodegradation processes, the methods for testing anaerobic biodegradability, and the anaerobic biodegradability of different detergent surfactant types (anionic, nonionic, cationic, amphoteric surfactants.

  12. Synthesis of flower-like Boehmite (AlOOH) via a simple solvothermal process without surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guangci [State Key Laboratory of Heavy Oil Processing, Key Laboratory of Catalysis, CNPC, China University of Petroleum, No. 66, Changjiang West Road, Qingdao 266555 (China); Liu, Yunqi, E-mail: liuyq@upc.edu.cn [State Key Laboratory of Heavy Oil Processing, Key Laboratory of Catalysis, CNPC, China University of Petroleum, No. 66, Changjiang West Road, Qingdao 266555 (China); Liu, Di; Liu, Lihua; Liu, Chenguang [State Key Laboratory of Heavy Oil Processing, Key Laboratory of Catalysis, CNPC, China University of Petroleum, No. 66, Changjiang West Road, Qingdao 266555 (China)

    2010-10-15

    Boehmite (AlOOH) with hierarchical flower-like structures was synthesized by the solvothermal reaction of AlCl{sub 3}.6H{sub 2}O in the presence of ethanol and toluene at 200 {sup o}C for 24 h. The product was characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that boehmite with flower-like nanostructures, which aggregated together by the weak hydrogen bonds, was formed through dissolution-deposition process of boehmite microcrystals and the toluene has a great effect on the morphology of product in the reaction system. Meanwhile, the {gamma}-Al{sub 2}O{sub 3} was also obtained by calcination of above product at 500 {sup o}C for 2 h, and the flower-like morphology kept no change. The surface area of {gamma}-Al{sub 2}O{sub 3} powder was determined to be 166.8 m{sup 2}/g by N{sub 2} adsorption measurement. The possible formation mechanism of flower-like boehmite nanostructures was proposed and discussed.

  13. Electrokinetic investigation of surfactant adsorption.

    Science.gov (United States)

    Bellmann, C; Synytska, A; Caspari, A; Drechsler, A; Grundke, K

    2007-05-15

    Fuerstenau [D.W. Fuerstenau, in: M.L. Hair (Ed.), Dekker, New York, 1971, p. 143] has already discussed the role of hydrocarbon chain of surfactants, the effect of alkyl chain length, chain structure and the pH of the solution on the adsorption process of surfactants. Later Kosmulski [M. Kosmulski, Chemical Properties of Material Surfaces, Surfactant Science Series, vol. 102, Dekker, New York, Basel, 2001] included the effect of surfactant concentration, equilibration time, temperature and electrolyte in his approaches. Certainly, the character of the head groups of the surfactant and the properties of the adsorbent surface are the basis for the adsorption process. Different surfactants and adsorbents cause different adsorption mechanisms described firstly by Rosen [M.J. Rosen, Surfactants and Interfacial Phenomena, second ed., Wiley, New York, 1989]. These adsorption mechanisms and their influencing factors were studied by electrokinetic investigations. Here only changes of the charges at the surfaces could be detected. To control the results of electrokinetic investigations they were compared with results from ellipsometric measurements. In the case of surfactant adsorption the chain length was vitally important. It could be shown by the adsorption of alkyl trimethyl ammonium bromides onto polymer films spin coated at wafer surfaces. The influence of the chain length depending on surface properties of the polymer film was studied. Streaming potential measurements were applied for these investigations. The obtained results enabled us to calculate the molar cohesive free energy per mol of CH2-group in the alkaline chain of the surfactant if all other specific adsorption effects were neglected.

  14. Climate change impacts on the seasonality and generation processes of floods in catchments with mixed snowmelt/rainfall regimes: projections and uncertainties

    Science.gov (United States)

    Vormoor, K.; Lawrence, D.; Heistermann, M.; Bronstert, A.

    2014-06-01

    Climate change is likely to impact the seasonality and generation processes of floods in the Nordic countries, which has direct implications for flood risk assessment, design flood estimation, and hydropower production management. Using a multi-model/multi-parameter approach, we analysed the projected changes in flood seasonality and its underlying generation processes in six catchments with mixed snowmelt/rainfall regimes in Norway. We found that autumn/winter events become more frequent in all catchments considered which leads to an intensification of the current autumn/winter flood regime for the coastal catchments, a reduction of the dominance of spring/summer flood regimes in a high-mountain catchment, and a possible systematic shift in the current flood regimes from spring/summer to autumn/winter in catchments in northern and south-eastern Norway. The changes in flood regimes results from increasing event magnitudes or frequencies, or a combination of both during autumn and winter. Changes towards more dominant autumn/winter events correspond to an increasing relevance of rainfall as a flood generating process (FGP) which is most pronounced in those catchments with the largest shifts in flood seasonality. Here, rainfall replaces snowmelt as the dominant FGP. We further analysed the ensemble components in contributing to overall uncertainty in the projected changes and found that the climate projections and the methods for downscaling or bias-correction tend to be the largest contributors. The relative role of hydrological parameter uncertainty, however, is highest for those catchments showing the largest changes in flood seasonality which confirms the lack of robustness in hydrological model parameterization for simulations under transient hydrometeorological conditions.

  15. Surfactant enhanced volumetric sweep efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, J.H.; Scamehorn, J.F.

    1989-10-01

    Surfactant-enhanced waterflooding is a novel EOR method aimed to improve the volumetric sweep efficiencies in reservoirs. The technique depends upon the ability to induce phase changes in surfactant solutions by mixing with surfactants of opposite charge or with salts of appropriate type. One surfactant or salt solution is injected into the reservoir. It is followed later by injection of another surfactant or salt solution. The sequence of injections is arranged so that the two solutions do not mix until they are into the permeable regions well away from the well bore. When they mix at this point, by design they form a precipitate or gel-like coacervate phase, plugging this permeable region, forcing flow through less permeable regions of the reservoir, improving sweep efficiency. The selectivity of the plugging process is demonstrated by achieving permeability reductions in the high permeable regions of Berea sandstone cores. Strategies were set to obtain a better control over the plug placement and the stability of plugs. A numerical simulator has been developed to investigate the potential increases in oil production of model systems. Furthermore, the hardness tolerance of anionic surfactant solutions is shown to be enhanced by addition of monovalent electrolyte or nonionic surfactants. 34 refs., 32 figs., 8 tabs.

  16. MICROBIAL SURFACTANTS IN ENVIRONMENTAL TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    T. P. Pirog

    2015-08-01

    Full Text Available It was shown literature and own experimental data concerning the use of microbial surface active glycolipids (rhamno-, sophoro- and trehalose lipids and lipopeptides for water and soil purification from oil and other hydrocarbons, removing toxic heavy metals (Cu2+, Cd2+, Ni2+, Pb2+, degradation of complex pollution (oil and other hydrocarbons with heavy metals, and the role of microbial surfactants in phytoremediation processes. The factors that limit the use of microbial surfactants in environmental technologies are discussed. Thus, at certain concentrations biosurfactant can exhibit antimicrobial properties and inhibit microorganisms destructing xenobiotics. Microbial biodegradability of surfactants may also reduce the effectiveness of bioremediation. Development of effective technologies using microbial surfactants should include the following steps: monitoring of contaminated sites to determine the nature of pollution and analysis of the autochthonous microbiota; determining the mode of surfactant introduction (exogenous addition of stimulation of surfactant synthesis by autochthonous microbiota; establishing an optimal concentration of surfactant to prevent exhibition of antimicrobial properties and rapid biodegradation; research both in laboratory and field conditions.

  17. Analysis of flash flood-triggering rainfall for a process-oriented hydrological model

    Science.gov (United States)

    Garambois, P. A.; Larnier, K.; Roux, H.; Labat, D.; Dartus, D.

    2014-02-01

    We propose an extended study of recent flood-triggering storms and resulting hydrological responses for catchments in the Pyrenean foothills up to the Aude region. For hydrometeorological sciences, it appears relevant to characterize flash floods and the storm that triggered them over various temporal and spatial scales. There are very few studies of extreme storm-caused floods in the literature covering the Mediterranean and highlighting, for example, the quickness and seasonality of this natural phenomenon. The present analysis is based on statistics that clarify the dependence between the spatial and temporal distributions of rainfall at catchment scale, catchment morphology and runoff response. Given the specific space and time scales of rainfall cell development, we show that the combined use of radar and a rain gauge network appears pertinent. Rainfall depth and intensity are found to be lower for catchments in the Pyrenean foothills than for the nearby Corbières or Montagne Noire regions. We highlight various hydrological behaviours and show that an increase in initial soil saturation tends to foster quicker catchment flood response times, of around 3 to 10 h. The hydrometeorological data set characterized in this paper constitutes a wealth of information to constrain a physics-based distributed model for regionalization purposes in the case of flash floods. Moreover, the use of diagnostic indices for rainfall distribution over catchment drainage networks highlights a unimodal trend in spatial temporal storm distributions for the entire flood dataset. Finally, it appears that floods in mountainous Pyrenean catchments are generally triggered by rainfall near the catchment outlet, where the topography is lower.

  18. Spectroscopic characterization approach to study surfactants effect on ZnO 2 nanoparticles synthesis by laser ablation process

    Science.gov (United States)

    Drmosh, Q. A.; Gondal, M. A.; Yamani, Z. H.; Saleh, T. A.

    2010-05-01

    Zinc peroxide nanoparticles having grain size less than 5 nm were synthesized using pulsed laser ablation in aqueous solution in the presence of different surfactants and solid zinc target in 3% H 2O 2. The effect of surfactants on the optical and structure of ZnO 2 was studied by applying different spectroscopic techniques. Structural properties and grain size of the synthesized nanoparticles were studied using XRD method. The presence of the cubic phase of zinc peroxide in all samples was confirmed with XRD, and the grain sizes were 4.7, 3.7, 3.3 and 2.8 nm in pure H 2O 2, and H 2O 2 mixed with SDS, CTAB and OGM respectively. For optical characterization, FTIR transmittance spectra of ZnO 2 nanoparticles prepared with and without surfactants show a characteristic ZnO 2 absorption at 435-445 cm -1. FTIR spectrum revealed that the adsorbed surfactants on zinc peroxide disappeared in case of CTAB and OGM while it appears in case of SDS. This could be due to high critical micelles SDS concentration comparing with others which is attributed to the adsorption anionic nature of this surfactant. Both FTIR and UV-vis spectra show a red shift in the presence of SDS and blue shift in the presence of CTAB and OGM. The blue shift in the absorption edge indicates the quantum confinement property of nanoparticles. The zinc peroxide nanoparticles prepared in additives-free media was also characterized by Raman spectra which show the characteristic peaks at 830-840 and 420-440 cm -1.

  19. Spectroscopic characterization approach to study surfactants effect on ZnO{sub 2} nanoparticles synthesis by laser ablation process

    Energy Technology Data Exchange (ETDEWEB)

    Drmosh, Q.A. [Laser Research Group, Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Center of Excellence in Nanotechnology (CENT), King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Gondal, M.A., E-mail: magondal@kfupm.edu.sa [Laser Research Group, Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Center of Excellence in Nanotechnology (CENT), King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Yamani, Z.H. [Laser Research Group, Physics Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Center of Excellence in Nanotechnology (CENT), King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Saleh, T.A. [Center of Excellence in Nanotechnology (CENT), King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2010-05-01

    Zinc peroxide nanoparticles having grain size less than 5 nm were synthesized using pulsed laser ablation in aqueous solution in the presence of different surfactants and solid zinc target in 3% H{sub 2}O{sub 2}. The effect of surfactants on the optical and structure of ZnO{sub 2} was studied by applying different spectroscopic techniques. Structural properties and grain size of the synthesized nanoparticles were studied using XRD method. The presence of the cubic phase of zinc peroxide in all samples was confirmed with XRD, and the grain sizes were 4.7, 3.7, 3.3 and 2.8 nm in pure H{sub 2}O{sub 2}, and H{sub 2}O{sub 2} mixed with SDS, CTAB and OGM respectively. For optical characterization, FTIR transmittance spectra of ZnO{sub 2} nanoparticles prepared with and without surfactants show a characteristic ZnO{sub 2} absorption at 435-445 cm{sup -1}. FTIR spectrum revealed that the adsorbed surfactants on zinc peroxide disappeared in case of CTAB and OGM while it appears in case of SDS. This could be due to high critical micelles SDS concentration comparing with others which is attributed to the adsorption anionic nature of this surfactant. Both FTIR and UV-vis spectra show a red shift in the presence of SDS and blue shift in the presence of CTAB and OGM. The blue shift in the absorption edge indicates the quantum confinement property of nanoparticles. The zinc peroxide nanoparticles prepared in additives-free media was also characterized by Raman spectra which show the characteristic peaks at 830-840 and 420-440 cm{sup -1}.

  20. A triplet-triplet annihilation based up-conversion process investigated in homogeneous solutions and oil-in-water microemulsions of a surfactant.

    Science.gov (United States)

    Penconi, Marta; Gentili, Pier Luigi; Massaro, Giuseppina; Elisei, Fausto; Ortica, Fausto

    2014-01-01

    The triplet-triplet annihilation based up-conversion process, involving a platinum octaethyl-porphyrin (PtOEP) as a sensitizer and tetraphenyl-pyrene (TPPy) as an emitter, has been investigated in homogeneous solutions of toluene, bromobenzene and anisole, and oil-in-water microemulsions of the TX-100 surfactant, where toluene constitutes the non-polar phase. In homogeneous solutions, the highest up-conversion quantum yield (of the order of 20%) has been achieved in toluene, being the solvent that has the lowest viscosity among those explored. The up-conversion emission from the PtOEP-TPPy pair has been then investigated in a toluene based oil-in-water microemulsion at three different concentrations of the solutes, showing quantum yields up to the order of 1%, under the same irradiation conditions, but different deoxygenating procedures. The results herein reported might represent a good starting point for a future investigation in microheterogeneous systems. An optimization of the microemulsion composition, in terms of surfactant, co-surfactant and toluene concentrations, could allow us to increase the sensitizer and emitter concentrations and set up the best operative conditions to obtain even higher up-conversion efficiencies.

  1. On the Difference between Self-Assembling Process of Monomeric and Dimeric Surfactants with the Same Head to Tail Ratio: A Lattice Monte Carlo Simulation

    Directory of Open Access Journals (Sweden)

    Reza Behjatmanesh-Ardakani

    2013-01-01

    Full Text Available Experimental data show that gemini surfactants have critical micelle concentrations that are almost tenfold lower than the CMCs of single chain ones. It is believed that the spacer groups play an important role in this subject. Short hydrophilic or long hydrophobic spacers can reduce CMC dramatically. In this paper, self-assembling processes of double-chain and one-chain surfactants with the same head to tail ratio are compared. Dimeric chain structure is exactly double of single chain. In other words, hydrophilic-lyophilic balances of two chain models are the same. Two single chains are connected head-to-head to form a dimeric chain, without introducing extra head or tail beads as a spacer group. Premicellar, micellar, and shape/phase transition ranges of both models are investigated. To do this, lattice Monte Carlo simulation in canonical ensemble has been used. Results show that without introducing extra beads as spacer group, the CMC of (H3T32 as a dimeric surfactant is much lower than the CMC of its similar single chain, H3T3. For dimeric case of study, it is shown that bolaform aggregates are formed.

  2. Separation of single-walled carbon nanotubes by gel-based chromatography using surfactant step-gradient techniques and development of new instrumentation for studying SWCNT reaction processes

    Science.gov (United States)

    Breindel, Leonard M.

    Single-walled carbon nanotube (SWCNT) synthesis methods such as CoMoCATTM, HiPcoTM, pulsed laser vaporization (PLV), and catalytic chemical vapor deposition (CCVD) produce several different distributions of (n,m) SWCNT structures, where ( n,m) defines the nanotube diameter and chiral wrapping angle. Post-synthesis processing such as functionalization and/or separations must therefore be employed to yield high purity electronic or single (n,m) samples. Through the use of a surfactant gradient across a gel-based chromatographic column, separations of single (n,m) species can be achieved. Anionic surfactants such as SDS, SDBS, and AOT display different separation effectiveness for single (n,m) species. Results of near-infrared optical absorption for separated SWCNT surfactant suspensions will be discussed, leading to a broader understanding of the important factors necessary for the gel chromatography separation technique. In particular, the effects of SWCNT/surfactant micelle structure are found to be key to achieving fast, simple SWCNT electronic type separations. Additionally, development of new instrumentation for the near-infrared spectrofluorimetric analysis (NIR-SFA) of SWCNTs is useful to the advancement of fundamental SWCNT research and applications. NIR-SFA, for instance, allows for the (n,m) structures of a sample to be identified and monitored during the progress of a chemical reaction or separation experiment. Seeking to achieve the time resolutions necessary for such experiments, the design and optimizations of a system utilizing single-wavelength excitation by diode lasers coupled with a fast NIR detection system are presented.

  3. Evaluation of the potential of alkali-surfactant-polymer (ASP) foams in enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Wang, L. A.; Romer-Zeron, L.; Kantzas, A. [University of Calgary, Dept. of Chemical and Petroleum Engineering, Calgary, AB (Canada)

    2004-07-01

    Results of a study of a new enhanced oil recovery technology, known as alkali-surfactant-polymer foams (ASPF), are discussed. The study was carried out through a series of laboratory core floods using sand packs and dead crude oil. The foaming solution was formulated using synthetic brine; a polycrylamide (AC 935) combined with the foaming surfactant (CD 1045) was chosen to provide the greatest gas mobility control capability and foam stability. Results demonstrated very high oil recovery efficiency resulting from ASPF flooding. Various combination of water flooding, foam flooding and gas flooding were investigated in an effort to determine the optimum injection scenarios for maximum oil recovery.

  4. A study of surfactant-assisted waterflooding

    Energy Technology Data Exchange (ETDEWEB)

    Scamehorn, J F; Harwell, J H

    1990-09-01

    In surfactant-assisted waterflooding, a surfactant slug is injected into a reservoir, followed by a brine spacer, followed by second surfactant slug. The charge on the surfactant in the first slug has opposite sign to that in the second slug. When the two slugs mix in the reservoir, a precipitate or coacervate is formed which plugs the permeable region of the reservoir. Subsequently injected water or brine is forced through the low permeability region of the reservoir, increasing sweep efficiency of the waterflood, compared to a waterflood not using surfactants. In this part of the work, two major tasks are performed. First, core floods are performed with oil present to demonstrate the improvement in incremental oil production, as well as permeability modification. Second, a reservoir simulation model will be proposed to further delineate the optimum strategy for implementation of the surfactant-assisted waterflooding, as well as indicate the reservoir types for which it would be most effective. Surfactants utilized were sodium dodecyl sulfate and dodecyl pyridinium chloride. 44 refs., 17 figs., 3 tabs.

  5. Synthesis and properties evaluation of sulfobetaine surfactant with double hydroxyl

    Science.gov (United States)

    Zhou, Ming; Luo, Gang; Zhang, Ze; Li, Sisi; Wang, Chengwen

    2017-09-01

    A series of sulfobetaine surfactants {N-[(3-alkoxy-2-hydroxyl)propoxy] ethyl-N,N-dimethyl-N-(2-hydroxyl)propyl sulfonate} ammonium chloride were synthesized with raw materials containing linear saturated alcohol, N,N-dimethylethanolamine, sodium 3-chloro-2-hydroxyl propane sulfonic acid and epichlorohydrin. The molecule structures of sulfobetaine surfactants were characterized by FTIR, 1HNMR and elemental analysis. Surface tension measurements can provide us information about the surface tension at the CMC (γCMC), pC20, Γmax and Amin. The pC20 values of sulfobetaine surfactants increase with the hydrophobic chain length increasing. Amin values of the surfactants decrease with increasing hydrophobic chain length from 10 to 14. The critical micelle concentration (CMC) and surface tension (γCMC) values of the sulfobetaine surfactants decrease with increasing hydrophobic chain length from 10 to 16. The lipophilicity of surfactant was enhanced with the increase of the carbon chain, however, the ability of anti-hard water was weakened. The minimum oil/water interfacial tension of four kinds of sulfobetaine surfactants is 10-2-10-3 mN/m magnitude, which indicates that the synthesized bis-hydroxy sulfobetaine surfactants have a great ability to reduce interfacial tension in the surfactant flooding system. The surface tension (γCMC) values of synthesized surfactants were lower compared with conventional anionic surfactant sodium dodecyl sulfonate.

  6. Numerical simulation of flood inundation processes by 2D shallow water equations

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xinhua; LONG Wenfei; XIE Heping; ZHU Jiahua; WANG Jiangping

    2007-01-01

    In order to strengthen flood risk management in a river basin,to upgrade the capability of flood control,and to reduce the loss of lives and properties in urban areas,a numerical simulation model using 2D shallow water equations was proposed in this study.A satisfactory result has been obtained by applying the model in the Fuji River basin in central Japan.The result indicates that the numerical:simulation model proposed can be adopted not only in the risk management of a river basin,but also in the study of realtime operations of rescue jobs and evacuation routes in a municipal region suffering from a serious flooding event.

  7. Biophysical inhibition of pulmonary surfactant function by polymeric nanoparticles: role of surfactant protein B and C.

    Science.gov (United States)

    Beck-Broichsitter, Moritz; Ruppert, Clemens; Schmehl, Thomas; Günther, Andreas; Seeger, Werner

    2014-11-01

    The current study investigated the mechanisms involved in the process of biophysical inhibition of pulmonary surfactant by polymeric nanoparticles (NP). The minimal surface tension of diverse synthetic surfactants was monitored in the presence of bare and surface-decorated (i.e. poloxamer 407) sub-100 nm poly(lactide) NP. Moreover, the influence of NP on surfactant composition (i.e. surfactant protein (SP) content) was studied. Dose-elevations of SP advanced the biophysical activity of the tested surfactant preparation. Surfactant-associated protein C supplemented phospholipid mixtures (PLM-C) were shown to be more susceptible to biophysical inactivation by bare NP than phospholipid mixture supplemented with surfactant protein B (PLM-B) and PLM-B/C. Surfactant function was hindered owing to a drastic depletion of the SP content upon contact with bare NP. By contrast, surface-modified NP were capable of circumventing unwanted surfactant inhibition. Surfactant constitution influences the extent of biophysical inhibition by polymeric NP. Steric shielding of the NP surface minimizes unwanted NP-surfactant interactions, which represents an option for the development of surfactant-compatible nanomedicines.

  8. Model parameters conditioning on regional hydrologic signatures for process-based design flood estimation in ungauged basins.

    Science.gov (United States)

    Biondi, Daniela; De Luca, Davide Luciano

    2015-04-01

    The use of rainfall-runoff models represents an alternative to statistical approaches (such as at-site or regional flood frequency analysis) for design flood estimation, and constitutes an answer to the increasing need for synthetic design hydrographs (SDHs) associated to a specific return period. However, the lack of streamflow observations and the consequent high uncertainty associated with parameter estimation, usually pose serious limitations to the use of process-based approaches in ungauged catchments, which in contrast represent the majority in practical applications. This work presents the application of a Bayesian procedure that, for a predefined rainfall-runoff model, allows for the assessment of posterior parameters distribution, using the limited and uncertain information available for the response of an ungauged catchment (Bulygina et al. 2009; 2011). The use of regional estimates of river flow statistics, interpreted as hydrological signatures that measure theoretically relevant system process behaviours (Gupta et al. 2008), within this framework represents a valuable option and has shown significant developments in recent literature to constrain the plausible model response and to reduce the uncertainty in ungauged basins. In this study we rely on the first three L-moments of annual streamflow maxima, for which regressions are available from previous studies (Biondi et al. 2012; Laio et al. 2011). The methodology was carried out for a catchment located in southern Italy, and used within a Monte Carlo scheme (MCs) considering both event-based and continuous simulation approaches for design flood estimation. The applied procedure offers promising perspectives to perform model calibration and uncertainty analysis in ungauged basins; moreover, in the context of design flood estimation, process-based methods coupled with MCs approach have the advantage of providing simulated floods uncertainty analysis that represents an asset in risk-based decision

  9. Branched alkyl alcohol propoxylated sulfate surfactants for improved oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.; Iglauer, S.; Shuler, P.; Tang, Y. [California Institute of Technology, Covina, CA (US). Power, Environmental and Energy Research (PEER) Center; Goddard, W.A. III [California Institute of Technology, Pasadena, CA (United States). Materials and Process Simulation Center

    2010-05-15

    This investigation considers branched alkyl alcohol propoxylated sulfate surfactants as candidates for chemical enhanced oil recovery (EOR) applications. Results show that these anionic surfactants may be preferred candidates for EOR as they can be effective at creating low interfacial tension (IFT) at dilute concentrations, without requiring an alkaline agent or cosurfactant. In addition, some of the formulations exhibit a low IFT at high salinity, and hence may be suitable for use in more saline reservoirs. Adsorption tests onto kaolinite clay indicate that the loss of these surfactants can be comparable to or greater than other types of anionic surfactants. Surfactant performance was evaluated in oil recovery core flood tests. Selected formulations recovered 35-50% waterflood residual oil even with dilute 0.2 wt% surfactant concentrations from Berea sandstone cores. (orig.)

  10. Efficient control system for low-concentration inorganic gases from a process vent stream: application of surfactants in spray and packed columns.

    Science.gov (United States)

    Chein, Hungmin; Aggarwal, Shankar G; Wu, Hsin-Hsien

    2004-11-01

    Control of low-concentration pollutants from a semiconductor process vent stream using a wet-scrubbing technique is a challenging task to meet Taiwan environmental emission standards. An efficient wet-scrubber is designed on a pilot scale and tested to control low concentration acid and base waste-gas emission. The scrubber system consisted of two columns, i.e., a fine spray column [cutoff diameter (based on volume), Dv(50) = 15.63 microm; Sauter mean diameter (SMD) = 7.62 microm], which is especially efficient for NH3 removal as the pH of the spraying liquid is approximately 7 followed by a packed column with a scrubbing liquid pH approximately 9.0 mainly for acids removal. It is observed that use of the surfactants in low concentration about 10(-4) M and 10(-7) M in the spray liquid and in the scrubbing liquid, respectively, remarkably enhances the removal efficiency of the system. A traditional packed column (without the spray column and the surfactant) showed that the removal efficiencies of NH3, HF, and HCl for the inlet concentration range 0.2 to 3 ppm were (n = 5) 22.6+/-3.4%, 43.4+/-5.5%, and 40.4+/-7.4%, respectively. The overall efficiencies of the proposed system (the spray column and the packed column) in the presence of the surfactant in the spray liquid and in the scrubbing liquid forthese three species were found to increase significantly (n = 5) from 60.3+/-3.6 to 82.8+/-6.8%, 59.1+/-2.7 to 83.4+/-4.2%, and 56.2+/-7.3 to 81.0+/-6.7%, respectively. In this work, development of charge on the gas-liquid interface due to the surfactants has been measured and discussed. It is concluded that the presence of charge on the gas-liquid interface is the responsible factor for enhancement of the removal efficiency (mass-transfer in liquid phase). The effects of the type of surfactants, their chain length, concentration in liquid, etc. on the removal efficiency are discussed. Since the pilot tests were performed under the operating conditions similar to most of

  11. Calorimetry is not color-blind.Molecular insights on association processes in surfactant-polymer mixtures derived from calorimetric experiments

    Institute of Scientific and Technical Information of China (English)

    LOH Watson; BRINATTI Cesar

    2012-01-01

    This comment will review and discuss recent results obtained with the use of calorimetry in assessing molecular information from complex phenomena such as association in surfactant/polymer mixtures.These examples were selected to support the view that it is possible to ally the great sensitivity of modern calorimeters with carefully planned experiments and,sometimes,ancillary techniques in order to derive detailed information on molecular interactions.

  12. IMPACTS OF FLOOD EVENTS IN COARSE SEDIMENT-PRODUCING AREAS ON CHANNEL SILTATION AND FLUVIAL PROCESS OF THE LOWER YELLOW RIVER

    Institute of Scientific and Technical Information of China (English)

    Ou-yang ZHANG; Xiufu FENG; Jiong-xin XU

    2007-01-01

    The method of multiple regression is used to analyze the influences of flood events from the coarse sediment producing areas on the channel siltation and fluvial process of the lower Yellow River based on the flood events from 1950 to 1985. The results showed that the flood events from the coarse sediment producing areas carry larger amounts of sediment load and coarser particle sizes than from other source areas, which increases deposition in the lower river channel. And there exist good correlations between channel siltation of the lower reaches of the Yellow River and the coming water and sediment of flood events from the coarse sediment producing areas. Through these correlations, the amounts of sediment deposition in the lower river channel could be roughly estimated based on the runoff and sediment load of flood events from the coarse sediment producing areas. The sediment deposition caused the fluvial process. There exists a complex response of channel form change to the coming water and sediment load of flood events from the coarse sediment producing areas. When the sediment concentration is smaller than 200kg/m3, the ratio between wide-depth ratio after flood and wide-depth ratio before flood((B/h)a / (B/h)b) will increase with the increase of the maximum sediment concentration; when the sediment concentration is near 200kg/m3, (B/h)a / (B/h)b reaches the maximum value; and when the sediment concentration reaches the limits of hyperconcentrated flow, (B/h)a / (B/h)b will decrease with the increase of the maximum sediment concentration. Generally, flood events from the coarse sediment producing areas made channel form of the lower Yellow River deeper and narrower, but a large amount of sediment deposition simultaneously occurs. So, the impacts of flood events from the coarse sediment producing areas on the channel of the lower Yellow River are lessened.

  13. Adsorption of dimeric surfactants in lamellar silicates

    Energy Technology Data Exchange (ETDEWEB)

    Balcerzak, Mateusz; Pietralik, Zuzanna [Department of Macromolecular Physics, Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland); Domka, Ludwik [Department of Metalorganic Chemistry, Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznań (Poland); Skrzypczak, Andrzej [Institute of Chemical Technology, Poznań University of Technology, Berdychowo 4, 60-965 Poznań (Poland); Kozak, Maciej, E-mail: mkozak@amu.edu.pl [Department of Macromolecular Physics, Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznań (Poland)

    2015-12-01

    Highlights: • The intercalation of dimeric surfactants changed the morphology of MMT samples. • XRD indicated structures formed by surfactant molecules in interlayer space. • The four-step thermal decomposition of dimeric surfactant, confirms intercalation. - Abstract: The adsorption of different types of cationic surfactants in lamellar silicates changes their surface character from hydrophilic to hydrophobic. This study was undertaken to obtain lamellar silicates modified by a series of novel dimeric (gemini) surfactants of different length alkyl chains and to characterise these organophilised materials. Synthetic sodium montmorillonite SOMASIF® ME 100 (M) and enriched bentonite of natural origin (Nanoclay – hydrophilic bentonite®) were organophilised with dimeric (gemini) surfactants (1,1′-(1,4-butanediyl)bis(alkoxymethyl)imidazolium dichlorides). As a result of surfactant molecule adsorption in interlamellar space, the d-spacing (d{sub 001}) increased from 0.97 nm (for the anhydrous structure) to 2.04 nm. A Fourier transform infrared spectroscopy (FTIR) analysis of the modified systems reveals bands assigned to the stretching vibrations of the CH{sub 2} and CH{sub 3} groups and the scissoring vibrations of the NH group from the structure of the dimeric surfactants. Thermogravimetric (TG) and derivative thermogravimetric (DTG) studies imply a four-stage process of surfactant decomposition. Scanning electron microscopy (SEM) images provide information on the influence of dimeric surfactant intercalation into the silicate structures. Particles of the modified systems show a tendency toward the formation of irregularly shaped agglomerates.

  14. Influence of river floods on the humification process in the bottom sediments from the Goczałkowice reservoir

    Directory of Open Access Journals (Sweden)

    Czerwieńska Karolina

    2016-06-01

    Full Text Available The paper presents the results of studies on the influence of the 2010 Vistula flood on the humification process in the bottom sediments of the Goczałkowice Reservoir in southern Poland. Due to its location in the vicinity of farmlands, forests and urbanized areas, the Goczałkowice Reservoir is characterized by amplified and intense humification processes within its sediments. The studies were focused on the determining the influence of the flood wave containing organic and inorganic suspensions on these processes. Humic acids were analyzed using two spectroscopic methods: Electron Paramagnetic Resonance (EPR and Fourier Transform Infrared Spectroscopy (FT-IR. Application of these methods allowed to determine the values of free radicals and of the g-factor, which are indicators of oxidation, aromatization and maturation of humic acids during the humification process, as well as the value of the 1650/1720 ratio, reflecting the dissociation of the COOH group to COO− and the formation of complexes of transitional metals with humic acids during the humification process.

  15. Dynamic Optimization of a Polymer Flooding Process Based on Implicit Discrete Maximum Principle

    Directory of Open Access Journals (Sweden)

    Yang Lei

    2012-01-01

    Full Text Available Polymer flooding is one of the most important technologies for enhanced oil recovery (EOR. In this paper, an optimal control model of distributed parameter systems (DPSs for polymer injection strategies is established, which involves the performance index as maximum of the profit, the governing equations as the fluid flow equations of polymer flooding, and some inequality constraints as polymer concentration and injection amount limitation. The optimal control model is discretized by full implicit finite-difference method. To cope with the discrete optimal control problem (OCP, the necessary conditions for optimality are obtained through application of the calculus of variations and Pontryagin’s discrete maximum principle. A modified gradient method with new adjoint construction is proposed for the computation of optimal injection strategies. The numerical results of an example illustrate the effectiveness of the proposed method.

  16. Multiple flow processes accompanying a dam-break flood in a small upland watershed, Centralia, Washington

    Science.gov (United States)

    Costa, John E.

    1994-01-01

    On October 5, 1991, following 35 consecutive days of dry weather, a 105-meter long, 37-meter wide, 5.2-meter deep concrete-lined watersupply reservoir on a hillside in the eastern edge of Centralia, Washington, suddenly failed, sending 13,250 cubic meters of water rushing down a small, steep tributary channel into the city. Two houses were destroyed, several others damaged, mud and debris were deposited in streets, on lawns, and in basements over four city blocks, and 400 people were evacuated. The cause of failure is believed to have been a sliding failure along a weak seam or joint in the siltstone bedrock beneath the reservoir, possibly triggered by increased seepage into the rock foundation through continued deterioration of concrete panel seams, and a slight rise (0.6 meters) in the pool elevation. A second adjacent reservoir containing 18,900 cubic meters of water also drained, but far more slowly, when a 41-cm diameter connecting pipe was broken by the landslide. The maximum discharge resulting from the dam-failure was about 71 cubic meters per second. A reconstructed hydrograph based on the known reservoir volume and calculated peak discharge indicates the flood duration was about 6.2 minutes. Sedimentologic evidence, high-water mark distribution, and landforms preserved in the valley floor indicate that the dam failure flood consisted of two flow phases: an initial debris flow that deposited coarse bouldery sediment along the slope-area reach as it lost volume, followed soon after by a water-flood that achieved a stage about one-half meter higher than the debris flow. The Centralia dam failure is one of three constructed dams destroyed by rapid foundation failure that defines the upper limits of an envelope curve of peak flood discharge as a function of potential energy for failed constructed dams worldwide.

  17. Removal of surfactants from water by adsorption on activated carbon and advanced oxidation process; Eliminacion de surfactantes de las aguas mediante adsorcion sobre carbon activado y oxidacion avanzada

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Diaz, J. D.; Sanchez Polo, M.; Rivera Utrilla, J.; Bautista, M. I.

    2007-07-01

    The objective of this study was to analyze the elimination process of surfactants from water, using sodium dode-cilbencenesulfonate (SDBS) as model compound, by means of adsorption on activated carbons as well as different processes of advanced oxidation (O{sub 3}, O{sub 3}/H{sub 2}O{sub 2} and O{sub 3}/activated carbon). Results obtained have shown that the activated carbons used have a high efficiency to eliminate SDBS from waters which was enhanced when the adsorption process was carried out in the presence of bacteria. With regard to the oxidation processes studied, the results have indicated that the efficiency in the elimination of SDBS from water of the system based on the simultaneous use of O{sub 3} and powder activated carbon (PAC) is much higher than those of the other systems studied (O{sub 3},O{sub 3}/H{sub 2}O{sub 2}). (Author) 15 refs.

  18. MICROBIAL SURFACTANTS. II. LIPOPEPTIDES

    Directory of Open Access Journals (Sweden)

    T. P. Pirog

    2014-04-01

    Full Text Available The classification and the chemical structure of the lipopeptides and their producers (bacteria of the genera Bacillus and Pseudomonas are given. The role of the lipopeptides in cells motility, biofilm formation, metal binding and xenobiotics degradation and their action on the cells of pro- and eukaryotes is summarized. The stages of the nonribosomal lipopeptides synthesis and the role of two-component (GacA/GacS, ComA/ComP and the quorum system regulation of this process are shown. The potential of lactic acid bacteria and marine microorganisms as alternative surfactants producers (glycolipids, lipopeptides, phospholipids and fatty acids, glycolipopeptides are discussed. Their productivity and advantages over traditional producers are given as well. The properties of surfactants synthesized by lactic acid bacteria (the reduction of the surface tension, the critical micelle concentration, the stability in a wide range of pH, the temperature, the biological activity are summarized. Surfactants of nonpathogenic probiotic bacteria could be used as effective antimicrobial agents and antiadhesive and marine producers which able to synthesize unique metabolites that are not produced by other microorganisms.

  19. Evaluation and Optimization Study on a Hybrid EOR Technique Named as Chemical-Alternating-Foam Floods

    Directory of Open Access Journals (Sweden)

    Xu Xingguang

    2017-01-01

    Full Text Available This work presents a novel Enhanced Oil Recovery (EOR method called Chemical-Alternating-Foam (CAF floods in order to overcome the drawbacks of the conventional foam flooding such as insufficient amount of in-situ foams, severe foam collapse and surfactant retention. The first part of this research focused on the comparison of conventional foam floods and CAF floods both of which had the same amount of gas and chemicals. It showed that: (1 CAF floods possessed the much greater Residual Resistance Factor (RRF at elevated temperature; (2 the accumulative oil recovery of the CAF floods was 10%-15% higher than that of the conventional foam flooding. After 1.8 Pore Volume (PV injection, the oil recovery reached the plateau for both methods; (3 CAF floods yielded the most amount of incremental oil at the 98% water cut (water content in the effluent, while the continuous foam floods achieved the best performance at 60% water cut. The second part of this work determined the optimal foam quality (gas/liquid ratio or the volume percent gas within foam, chemical/foam slug size ratio, cycle number and injection sequence for the CAF floods. It was found that the CAF was endowed with the peak performance if the foam quality, chemical/foam slug size ratio, cycle number was fixed at 80%, 1:1 and 3 respectively with the chemical slug being introduced ahead of the foam slug. Through systematic and thorough research, the proposed hybrid process has been approved to be a viable and effective method significantly strengthening the conventional foam flooding.

  20. Coupling the Alkaline-Surfactant-Polymer Technology and The Gelation Technology to Maximize Oil Production

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson; Phil Dowling; David Stewart; Bill Jones

    2005-12-01

    Performance and produced polymer evaluation of four alkaline-surfactant-polymer projects concluded that only one of the projects could have benefited from combining the alkaline-surfactant-polymer and gelation technologies. Cambridge, the 1993 Daqing, Mellott Ranch, and the Wardlaw alkaline-surfacant-polymer floods were studied. An initial gel treatment followed by an alkaline-surfactant-polymer flood in the Wardlaw field would have been a benefit due to reduction of fracture flow. Numerical simulation demonstrated that reducing the permeability of a high permeability zone of a reservoir with gel improved both waterflood and alkaline-surfactant-polymer flood oil recovery. A Minnelusa reservoir with both A and B sand production was simulated. A and B sands are separated by a shale layer. A sand and B sand waterflood oil recovery was improved by 196,000 bbls or 3.3% OOIP when a gel was placed in the B sand. Alkaline-surfactant-polymer flood oil recovery improvement over a waterflood was 392,000 bbls or 6.5% OOIP. Placing a gel into the B sand prior to an alkaline-surfactant-polymer flood resulted in 989,000 bbl or 16.4% OOIP more oil than only water injection. A sand and B sand alkaline-surfactant-polymer flood oil recovery was improved by 596,000 bbls or 9.9% OOIP when a gel was placed in the B sand.

  1. An algorithm for emulsion stability simulations: account of flocculation, coalescence, surfactant adsorption and the process of Ostwald ripening.

    Science.gov (United States)

    Urbina-Villalba, German

    2009-03-01

    The first algorithm for Emulsion Stability Simulations (ESS) was presented at the V Conferencia Iberoamericana sobre Equilibrio de Fases y Diseño de Procesos [Luis, J.; García-Sucre, M.; Urbina-Villalba, G. Brownian Dynamics Simulation of Emulsion Stability In: Equifase 99. Libro de Actas, 1(st) Ed., Tojo J., Arce, A., Eds.; Solucion's: Vigo, Spain, 1999; Volume 2, pp. 364-369]. The former version of the program consisted on a minor modification of the Brownian Dynamics algorithm to account for the coalescence of drops. The present version of the program contains elaborate routines for time-dependent surfactant adsorption, average diffusion constants, and Ostwald ripening.

  2. DILUTE SURFACTANT METHODS FOR CARBONATE FORMATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Kishore K. Mohanty

    2005-01-01

    There are many carbonate reservoirs in US (and the world) with light oil and fracture pressure below its minimum miscibility pressure (or reservoir may be naturally fractured). Many carbonate reservoirs are naturally fractured. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). Thermal and miscible tertiary recovery techniques are not effective in these reservoirs. Surfactant flooding (or huff-n-puff) is the only hope, yet it was developed for sandstone reservoirs in the past. The goal of this research is to evaluate dilute (hence relatively inexpensive) surfactant methods for carbonate formations and identify conditions under which they can be effective. Imbibition in an originally oil-wet 2D capillary is the fastest in the case of Alf-38 and slowest in the case of DTAB (among the surfactants studied). Force of adhesion studies and contact angle measurements show that greater wettability alteration is possible with these anionic surfactants than the cationic surfactant studied. The water imbibition rate does not increase monotonically with an increase in the surfactant concentration. A numerical model has been developed that fits the rate of imbibition. Plans for the next quarter include conducting simulation and imbibition studies.

  3. Interactions of organic contaminants with mineral-adsorbed surfactants

    Science.gov (United States)

    Zhu, L.; Chen, B.; Tao, S.; Chiou, C.T.

    2003-01-01

    Sorption of organic contaminants (phenol, p-nitrophenol, and naphthalene) to natural solids (soils and bentonite) with and without myristylpyridinium bromide (MPB) cationic surfactant was studied to provide novel insight to interactions of contaminants with the mineral-adsorbed surfactant. Contaminant sorption coefficients with mineral-adsorbed surfactants, Kss, show a strong dependence on surfactant loading in the solid. At low surfactant levels, the Kss values increased with increasing sorbed surfactant mass, reached a maximum, and then decreased with increasing surfactant loading. The Kss values for contaminants were always higher than respective partition coefficients with surfactant micelles (Kmc) and natural organic matter (Koc). At examined MPB concentrations in water the three organic contaminants showed little solubility enhancement by MPB. At low sorbed-surfactant levels, the resulting mineral-adsorbed surfactant via the cation-exchange process appears to form a thin organic film, which effectively "adsorbs" the contaminants, resulting in very high Kss values. At high surfactant levels, the sorbed surfactant on minerals appears to form a bulklike medium that behaves essentially as a partition phase (rather than an adsorptive surface), with the resulting Kss being significantly decreased and less dependent on the MPB loading. The results provide a reference to the use of surfactants for remediation of contaminated soils/sediments or groundwater in engineered surfactant-enhanced washing.

  4. Fluorescence of aminofluoresceins as an indicative process allowing one to distinguish between micelles of cationic surfactants and micelle-like aggregates

    Science.gov (United States)

    Mchedlov-Petrossyan, Nikolay O.; Cheipesh, Tatiana A.; Roshal, Alexander D.; Doroshenko, Andrey O.; Vodolazkaya, Natalya A.

    2016-09-01

    Among the vast set of fluorescein derivatives, the double charged R2- anions of aminofluoresceins are known to exhibit only low quantum yields of fluorescence, \\varphi . The \\varphi value becomes as high as that of the fluorescein dianion when the lone electron pair of the amino group is involved in a covalent bond. According to Munkholm et al (1990 J. Am. Chem. Soc. 112 2608-12), a much smaller increase in the emission intensity can be observed in the presence of surfactant micelles. However, all these observations refer to aqueous or alcoholic solvents. In this paper, we show that in the non-hydrogen bond donor (or ‘aprotic’) solvents DMSO and acetone, the quantum yields, φ, of the 4‧- (or 5‧)-aminofluorescein R2- species amount to 61-67% and approach that of fluorescein (φ  =  87%), whereas in water φ is only 0.6-0.8%. In glycerol, a solvent with an extremely high viscosity, the φ value is only 6-10%. We report on the enhancement of the fluorescence of the aminofluorescein dianions as an indicative process, which allows us to distinguish between the micelle-like aggregates of cationic dendrimers of low generation, common spherical surfactant micelles, and surfactant bilayers. Some of these colloidal aggregates partly restore the fluorescence of aminofluoresceins in aqueous media. By contrast, other positively charged micellar-like aggregates do not enhance the quantum yield of aminofluorescein R2- species. Results for several related systems, such as CTAB-coated SiO2 particles and reverse microemulsions, are briefly described, and the possible reasons for the observed phenomena are discussed.

  5. Effect of surfactant concentration on characteristics of mesoporous bioactive glass prepared by evaporation induced self-assembly process

    Science.gov (United States)

    Shih, Chi-Chung; Chien, Chi-Sheng; Kung, Jung-Chang; Chen, Jian-Chih; Chang, Shy-Shin; Lu, Pei-Shan; Shih, Chi-Jen

    2013-01-01

    Mesoporous bioactive glasses were prepared by the evaporation-induced self-assembly method. The main objective of the present study is to determine the effect of surfactant concentration on the synthesis of SiO2-CaO-P2O5 mesoporous bioactive glasses; the characterization techniques used include X-ray diffraction, scanning electron microscopy and nitrogen adsorption and desorption isotherms. The results show that the specific surface area initially increased with increasing surfactant concentrations in the range of 2.1-9.1 wt% and significantly decreased from 328.7 to 204.0 m2/g in the concentration range of 9.1-12.5 wt%. For texture evaluation, the selected area electron diffraction patterns of the mesoporous bioactive glass precursor gels (9.1 wt% F127) calcined at different temperatures were analyzed; these patterns support the notion that some glassy structures in bioactive glasses become crystalline following heat treatment. The scanning electron microscopy images and X-ray diffraction patterns obtained agree with the inductively coupled plasma with atomic emission spectroscopy results as the mesoporous bioactive glasses can induce the formation of an apatite-like layer on their surface in SBF, even after short soaking periods.

  6. Improving Gas Flooding Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reid Grigg; Robert Svec; Zheng Zeng; Alexander Mikhalin; Yi Lin; Guoqiang Yin; Solomon Ampir; Rashid Kassim

    2008-03-31

    This study focuses on laboratory studies with related analytical and numerical models, as well as work with operators for field tests to enhance our understanding of and capabilities for more efficient enhanced oil recovery (EOR). Much of the work has been performed at reservoir conditions. This includes a bubble chamber and several core flood apparatus developed or modified to measure interfacial tension (IFT), critical micelle concentration (CMC), foam durability, surfactant sorption at reservoir conditions, and pressure and temperature effects on foam systems.Carbon dioxide and N{sub 2} systems have been considered, under both miscible and immiscible conditions. The injection of CO2 into brine-saturated sandstone and carbonate core results in brine saturation reduction in the range of 62 to 82% brine in the tests presented in this paper. In each test, over 90% of the reduction occurred with less than 0.5 PV of CO{sub 2} injected, with very little additional brine production after 0.5 PV of CO{sub 2} injected. Adsorption of all considered surfactant is a significant problem. Most of the effect is reversible, but the amount required for foaming is large in terms of volume and cost for all considered surfactants. Some foams increase resistance to the value beyond what is practical in the reservoir. Sandstone, limestone, and dolomite core samples were tested. Dissolution of reservoir rock and/or cement, especially carbonates, under acid conditions of CO2 injection is a potential problem in CO2 injection into geological formations. Another potential change in reservoir injectivity and productivity will be the precipitation of dissolved carbonates as the brine flows and pressure decreases. The results of this report provide methods for determining surfactant sorption and can be used to aid in the determination of surfactant requirements for reservoir use in a CO{sub 2}-foam flood for mobility control. It also provides data to be used to determine rock permeability

  7. Thermally cleavable surfactants

    Science.gov (United States)

    McElhanon, James R.; Simmons, Blake A.; Zifer, Thomas; Jamison, Gregory M.; Loy, Douglas A.; Rahimian, Kamyar; Long, Timothy M.; Wheeler, David R.; Staiger, Chad L.

    2006-04-04

    Two new surfactant molecules are reported which contain thermally labile Diels-Alder adducts connecting the polar and non-polar sections of each molecule. The two surfactants possess identical non-polar dodecyl tail segments but exhibit different polar headgroups. The surfactants become soluble in water when anionic salts are formed through the deprotonation of the surfactant headgroups by the addition of potassium hydroxide. When either surfactant is exposed to temperature above about 60.degree. C., the retro Diels-Alder reaction occurs, yielding hydrophilic and hydrophobic fragments and the aqueous solutions of the surfactants subsequently exhibit loss of all surface-active behavior.

  8. Thermally cleavable surfactants

    Energy Technology Data Exchange (ETDEWEB)

    McElhanon, James R. (Manteca, CA); Simmons, Blake A. (San Francisco, CA); Zifer, Thomas (Manteca, CA); Jamison, Gregory M. (Albuquerque, NM); Loy, Douglas A. (Albuquerque, NM); Rahimian, Kamyar (Albuquerque, NM); Long, Timothy M. (Urbana, IL); Wheeler, David R. (Albuquerque, NM); Staiger, Chad L. (Albuquerque, NM)

    2009-09-29

    Two new surfactant molecules are reported which contain thermally labile Diels-Alder adducts connecting the polar and non-polar sections of each molecule. The two surfactants possess identical non-polar dodecyl tail segments but exhibit different polar headgroups. The surfactants become soluble in water when anionic salts are formed through the deprotonation of the surfactant headgroups by the addition of potassium hydroxide. When either surfactant is exposed to temperature above about 60.degree. C., the retro Diels-Alder reaction occurs, yielding hydrophilic and hydrophobic fragments or the aqueous solutions of the surfactants subsequently exhibit loss of all surface-active behavior.

  9. Thermally cleavable surfactants

    Energy Technology Data Exchange (ETDEWEB)

    McElhanon, James R. (Manteca, CA); Simmons, Blake A. (San Francisco, CA); Zifer, Thomas (Manteca, CA); Jamison, Gregory M. (Albuquerque, NM); Loy, Douglas A. (Albuquerque, NM); Rahimian, Kamyar (Albuquerque, NM); Long, Timothy M. (Urbana, IL); Wheeler, David R. (Albuquerque, NM); Staiger, Chad L. (Albuquerque, NM)

    2009-11-24

    Two new surfactant molecules are reported which contain thermally labile Diels-Alder adducts connecting the polar and non-polar sections of each molecule. The two surfactants possess identical non-polar dodecyl tail segments but exhibit different polar headgroups. The surfactants become soluble in water when anionic salts are formed through the deprotonation of the surfactant headgroups by the addition of potassium hydroxide. When either surfactant is exposed to temperature above about 60.degree. C., the retro Diels-Alder reaction occurs, yielding hydrophilic and hydrophobic fragments or the aqueous solutions of the surfactants subsequently exhibit loss of all surface-active behavior.

  10. Using biologically soft surfactants for dust suppression

    Energy Technology Data Exchange (ETDEWEB)

    Tkachenko, N.G.; Kolodiichak, V.K.; Motrii, A.E.; Severin, V.D.

    1982-07-01

    This article discusses environmental aspects of using surfactants in coal mines for dust suppression. Surfactants for underground black coal mines in the USSR are divided into three classes: so-called soft surfactants with a decomposition period from 1 to 3 days, hard surfactants with decomposition exceeding a month and an intermediary group. The decomposition process is analyzed; the role played by fermentation is stressed. Environmental effects of surfactant decomposition are evaluated. Selected surfactants tested in Soviet laboratories are described. The results of experimental use of diethanolamide as a surfactant for water injection in coal seams are evaluated. Wetting time amounts to 1 s when a 0.2% concentration is used. When surfactant concentration in water is reduced to 0.05% wetting time does not change; when concentration decreases to 0.025% wetting time increases to 3 s. Surfactant efficiency is investigated under operational conditions in a Donbass mine. Specifications of the working face, mining system and air pollution caused by a shearer loader are discussed. When diethanolamide is used dust suppression efficiency ranges from 86.4 to 90.4%. During the tests diethanolamide concentration in water was 0.05%.

  11. A simple route utilizing surfactant-assisted templating sol-gel process for synthesis of mesoporous Dy2O3 nanocrystal.

    Science.gov (United States)

    Sreethawong, Thammanoon; Chavadej, Sumaeth; Ngamsinlapasathian, Supachai; Yoshikawa, Susumu

    2006-08-01

    A simple route of combined sol-gel process with surfactant-assisted templating technique was successfully employed for the first time to synthesize nanocrystalline mesoporous Dy(2)O(3) with narrow monomodal pore size distribution under mild conditions. The nanocrystalline Dy(2)O(3) with monomodal mesoporous characteristic was ultimately achieved by controlling the hydrolysis and condensation steps of dysprosium n-butoxide modified with acetylacetone in the presence of laurylamine hydrochloride surfactant aqueous solution. The synthesized material was methodically characterized by thermogravimetry and differential thermal analysis (TG-DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), selected-area electron diffraction (SAED), N(2) adsorption-desorption, Brunauer-Emmett-Teller (BET) surface area analysis, and Barrett-Joyner-Halenda (BJH) pore size distribution analysis. The particle size of the synthesized Dy(2)O(3) in nanosized range obtained from the SEM and HRTEM micrographs was in good accordance with the crystallite size estimated from the XRD result. The N(2) adsorption-desorption result exhibited hysteresis pattern with single loop, indicating the existence of monomodal mesopore. The extremely narrow pore size distribution with mean pore diameter in the mesopore region of the synthesized Dy(2)O(3) was also confirmed by the BJH result.

  12. Climate change impacts on the seasonality and generation processes of floods - projections and uncertainties for catchments with mixed snowmelt/rainfall regimes

    Science.gov (United States)

    Vormoor, K.; Lawrence, D.; Heistermann, M.; Bronstert, A.

    2015-02-01

    Climate change is likely to impact the seasonality and generation processes of floods in the Nordic countries, which has direct implications for flood risk assessment, design flood estimation, and hydropower production management. Using a multi-model/multi-parameter approach to simulate daily discharge for a reference (1961-1990) and a future (2071-2099) period, we analysed the projected changes in flood seasonality and generation processes in six catchments with mixed snowmelt/rainfall regimes under the current climate in Norway. The multi-model/multi-parameter ensemble consists of (i) eight combinations of global and regional climate models, (ii) two methods for adjusting the climate model output to the catchment scale, and (iii) one conceptual hydrological model with 25 calibrated parameter sets. Results indicate that autumn/winter events become more frequent in all catchments considered, which leads to an intensification of the current autumn/winter flood regime for the coastal catchments, a reduction of the dominance of spring/summer flood regimes in a high-mountain catchment, and a possible systematic shift in the current flood regimes from spring/summer to autumn/winter in the two catchments located in northern and south-eastern Norway. The changes in flood regimes result from increasing event magnitudes or frequencies, or a combination of both during autumn and winter. Changes towards more dominant autumn/winter events correspond to an increasing relevance of rainfall as a flood generating process (FGP) which is most pronounced in those catchments with the largest shifts in flood seasonality. Here, rainfall replaces snowmelt as the dominant FGP primarily due to increasing temperature. We further analysed the ensemble components in contributing to overall uncertainty in the projected changes and found that the climate projections and the methods for downscaling or bias correction tend to be the largest contributors. The relative role of hydrological

  13. Modelling cascading and erosional processes for glacial lake outburst floods in the Quillcay catchment, Huaraz, Cordillera Blanca, Peru

    Science.gov (United States)

    Baer, Patrick; Huggel, Christian; Frey, Holger; Chisolm, Rachel; McKinney, Daene; McArdell, Brian; Portocarrero, Cesar; Cochachin, Alejo

    2016-04-01

    Huaraz as the largest city in Cordillera Blanca has faced a major disaster in 1941, when an outburst flood from Lake Palcacocha killed several thousand people and caused widespread destruction. Recent studies on glacial lake outburst flood (GLOF) modelling and early warning systems focussed on Lake Palcacocha which has regrown after the 1941 event, from a volume of half a million m3 in 1974 to a total volume of more than 17 million m3 today. However, little research has been conducted so far concerning the situation of other lakes in the Quillcay catchment, namely Lake Tullparaju (12 mill. m3) and Cuchillacocha (2.5 mill. m3), which both also pose a threat to the city of Huaraz. In this study, we modelled the cascading processes at Lake Tullparaju and Lake Cuchillacocha including rock/ice avalanches, flood wave propagation in the lake and the resulting outburst flood and debris flows. We used the 2D model RAMMS to simulate ice avalanches. Model output was used as input for analytical 2D and 3D calculations of impact waves in the lakes that allowed us to estimate dam overtopping wave height. Since the dimension of the hanging glaciers above all three lakes is comparable, the scenarios in this study have been defined similar to the previous study at Lake Palcacocha. The flow propagation model included sediment entrainment in the steeper parts of the catchment, adding up to 50% to the initial flow volume. The results for total travel time as well as for inundated areas and flow depth and velocity in the city of Huaraz are comparable to the previous studies at Lake Palcacocha. This underlines the importance of considering also these lakes within an integral hazard analysis for the city of Huaraz. A main challenge for modelling GLOFs in the Quillcay catchment using RAMMS is the long runout distance of over 22 km combined with the very low slope gradient of the river. Further studies could improve the process understanding and could focus on more detailed investigations

  14. How Philadelphia is Integrating Climate Science and Policy: Changing Capital Planning Processes and Developing Flood-Depth Tools

    Science.gov (United States)

    Bhat, C.; Dix, B.; Choate, A.; Wong, A.; Asam, S.; Schultz, P. A.

    2016-12-01

    Policy makers can implement more effective climate change adaptation programs if they are provided with two tools: accessible information on the impacts that they need to prepare for, and clear guidance on how to integrate climate change considerations into their work. This presentation will highlight recent and ongoing efforts at the City of Philadelphia to integrate climate science into their decision-making. These efforts include developing a climate change information visualization tool, climate change risk assessments across the city, and processes to integrate climate change into routine planning and budgeting practices. The goal of these efforts is to make climate change science highly targeted to decision maker needs, non-political, easily accessible, and actionable. While sea level rise inundation maps have been available to communities for years, the maps do not effectively communicate how the design of a building or a piece of infrastructure would need to be modified to protect it. The Philadelphia Flood Risk Viewer is an interactive planning tool that allows Philadelphia to identify projected depths of flooding for any location within the City, for a variety of sea level rise and storm surge scenarios. Users can also determine whether a location is located in a FEMA floodplain. By having access to information on the projected depth of flooding at a given location, the City can determine what flood protection measures may be effective, or even inform the long-term viability of developing a particular area. With an understanding of climate vulnerabilities, cities have the opportunity to make smart, climate-resilient investments with their capital budgets that will yield multiple benefits for years to come. Few, however, have established protocols for doing so. Philadelphia, with support from ICF, developed a guidance document that identifies recommendations for integrating climate change considerations throughout the Capital Program and capital budgeting

  15. Improving oil recovery in the CO2 flooding process by utilizing nonpolar chemical modifiers☆

    Institute of Scientific and Technical Information of China (English)

    Yong Yang; Xiangliang Li; Ping Guo; Yayun Zhuo; Yong Sha

    2016-01-01

    By means of experiments of CO2 miscibility with crude oil, four nonpolar chemicals were evaluated in order to enhance the miscibility of CO2 with crude oil. Through pre-slug injection and joint injection of toluene in CO2, crude oil displacement experiments in the slim-tube were conducted to investigate effects of the toluene-enhanced CO2 flooding under simulated subterranean reservoir conditions. Experimental results showed that toluene can enhance extraction of oil into CO2 and dissolution of CO2 into oil with the increment of 251%and 64%respectively. Addition of toluene can obviously improve the oil recovery in either pre-slug injection or joint injection, and the crude oil recovery increased with the increase of the toluene concentration. The oil recov-ery can increase by 22.5%in pre-slug injection with the high toluene concentration. Pre-slug injection was recom-mended because it can consume less toluene than joint injection. This work could be useful to development and application of the CO2 flooding in the oil recovery as wel as CO2 emission reduction.

  16. Utilizing Multi-Sensor Data Products and high-resolution flood model in Analyzing North African Hydrological Processes

    Science.gov (United States)

    Thengumthara, K.; Policelli, F.; Habib, S.; David, J. L.; Melocik, K. A.; Huffman, G. J.; Anderson, M. C.; Ali, A. B.; Bacha, S.

    2013-12-01

    North Africa is an arid region characterized by isolated extreme events such as floods and droughts. Our present understanding of hydrological processes over North Africa is limited due to low rainfall, mixed response of evaporation to temperature and soil moisture gradients, and lack of high-resolution ground measurements. Remote sensing is an excellent way to obtain near real- time data of high spatial and temporal resolution. Satellite estimates of rainfall and evapotranspiration (ET) have uncertainties due to topography, land-sea contrast, complex weather, and climate variability for high-elevated regions. Generally for arid regions, the satellite precipitation instruments are sensitive to soil moisture and land surface geometry. This study analyzes different components of hydrological processes over North Africa based on remote sensing data such as precipitation (NASA-TMPA, CMORPH and PERSIANN), evaporation (ALEXI and MODIS), and elevation (SRTM) along with ground measurements and model simulations. Here we use the Coupled Routing and Excess STorage (CREST) hydrological model-version 2.0, which was originally developed by NASA-GSFC and the University of Oklahoma [Wang J et al., 2011]. The model is driven by real time TMPA and climatological PET, interpolated to model grids. The flexible simulation and calibration enables the model to provide high-resolution runoff and water depth at each time step. Our study mainly focuses on two major basins such as Medjerda over Tunisia and the Sebou basin of Morocco. Case studies of flood events over North Africa were analyzed based on CREST model simulations with respect to ground measurements. The floods are mainly modulated by rainfall associated with synoptic frontal and tropical plumes and orographic mesoscale systems. Occurrences of peak floods simulated by CREST are comparable with diagnostics such as vertically integrated moisture convergence, stratiform and convective precipitation from ECMWF reanalysis. These were

  17. Counterion identity effects on the self-assembly processes in a series of perfluorinated surfactant-water mixtures

    CERN Document Server

    Zhou, R

    2003-01-01

    The effects of counterion on the lyotropic liquid crystalline phase behaviour of some quaternary ammonium salts of perfluorodecanoic acid in water have been studied using a combination of optical polarising microscopy (OPM), deuterium nuclear magnetic resonance ( sup 2 H NMR) and cryo-transmission electron microscopy (cryo-TEM). The results from the phase diagram studies fall into two groups. Firstly the ammonium (A) and tetramethylammonium (TMA) counterions show a phase behaviour with nematic (N) and random mesh (Mh sub 1 (0)) phase which possess non-uniform interfacial curvature. The second group of surfactants with counterions, butyltrimethylammonium (BTMA), dibutyidimetylammonium (DBDMA), and tetrabutylammonium (TEA), form only a classical lamellar phase (L subalpha). For both DBDMA and TBA lower consolute behaviour has been observed. At fixed concentration in all five systems cryo-TEM visualises isotropic liquid phase structures that vary from sphere / rod micelles for A and TMA to vesicles / bilayer pie...

  18. Large wood recruitment processes and transported volumes in Swiss mountain streams during the extreme flood of August 2005

    Science.gov (United States)

    Steeb, Nicolas; Rickenmann, Dieter; Badoux, Alexandre; Rickli, Christian; Waldner, Peter

    2017-02-01

    The extreme flood event that occurred in August 2005 was the most costly (documented) natural hazard event in the history of Switzerland. The flood was accompanied by the mobilization of > 69,000 m3 of large wood (LW) throughout the affected area. As recognized afterward, wood played an important role in exacerbating the damages, mainly because of log jams at bridges and weirs. The present study aimed at assessing the risk posed by wood in various catchments by investigating the amount and spatial variability of recruited and transported LW. Data regarding LW quantities were obtained by field surveys, remote sensing techniques (LiDAR), and GIS analysis and was subsequently translated into a conceptual model of wood transport mass balance. Detailed wood budgets and transport diagrams were established for four study catchments of Swiss mountain streams, showing the spatial variability of LW recruitment and deposition. Despite some uncertainties with regard to parameter assumptions, the sum of reconstructed wood input and observed deposition volumes agree reasonably well. Mass wasting such as landslides and debris flows were the dominant recruitment processes in headwater streams. In contrast, LW recruitment from lateral bank erosion became significant in the lower part of mountain streams where the catchment reached a size of about 100 km2. According to our analysis, 88% of the reconstructed total wood input was fresh, i.e., coming from living trees that were recruited from adjacent areas during the event. This implies an average deadwood contribution of 12%, most of which was estimated to have been in-channel deadwood entrained during the flood event.

  19. The Alkali/Surfactant/ Polymer Process: Effects of Slug Size, Core Length and a Chase Polymer Le procédé alkali/surfactant/polymère : effets de la taille du bouchon, de la longueur de la carotte et d'un polymère de déplacement

    Directory of Open Access Journals (Sweden)

    Green K. A.

    2006-11-01

    Full Text Available An experimental study was conducted to examine the effects of slug size, core length, and a chase polymer on the effectiveness of the alkali/surfactant/polymer (A/S/P process in recovering waterflood residual oil. Core flood experiments were conducted with unfired linear Berea sandstone cores. The tertiary oil recovery, oil cut, pressure drop, and chemical propagation were measured for each flood. Tertiary oil recovery significantly increased with the slug size up to 0. 5 of a pore volume. Increasing the slug size further resulted in a smaller incremental increase in oil recovery. A slight increase in tertiary oil recovery was obtained when small size A/S/P slugs were followed with achase polymer having a viscosity higher than the slug. The lack of oil recovery with small A/S/P slugs was due to the consumption and dilution of the injected chemicals, especially the synthetic surfactant, due to adsorption and dispersion. Increasing the core length by a factor of 4. 5 (from 9 to 40. 6 cm had no significant effect on tertiary oil recovery. Chemical propagation was found to be a function of core length (i. e. , core Peclet number and the size of the chase polymer slug. Increasing core length and employing a chase polymer maintained the integrity of the A/S/P slug by decreasing the effect of dispersion and minimizing the influence of viscous fingering at the tail of the A/S/P slug. Une étude expérimentale a été effectuée pour examiner les effets de la taille du bouchon, de la longueur de la carotte et de l'emploi d'un polymère de déplacement sur l'efficacité du procédé A/S/P (alkali/surfactant/polymère dans la récupération d'huile résiduelle par injection d'eau. Les expériences d'injection ont été faites avec des carottes rectilignes en grès de Berea vert. La récupération tertiaire du pétrole, la présence d'eau, la perte de charge et la propagation chimique ont été mesurées pour chaque injection. La récupération tertiaire du

  20. Aerobic biodegradation process of petroleum and pathway of main compounds in water flooding well of Dagang oil field.

    Science.gov (United States)

    Cai, Minmin; Yao, Jun; Yang, Huaijun; Wang, Ruixia; Masakorala, Kanaji

    2013-09-01

    Aerobic biodegradation of crude oil and its pathways were investigated via in vitro culture and GC-MS analysis in water flooding wells of Dagang oil field. The in vitro aerobic culture lasted 90 days when 99.0% of n-alkanes and 43.03-99.9% of PAHs were degraded and the biomarkers and their ratios were changed. The spectra of components in the residual oil showed the similar biodegradation between aerobic process of 90 days and degradation in reservoir which may last for some millions years, and the potential of serious aerobic biodegradation of petroleum in reservoir. 24 Metabolites compounds were separated and identified from aerobic culture, including fatty acid, naphthenic acid, aromatic carboxylic acid, unsaturated acid, alcohols, ketones and aldehydes. The pathways of alkanes and aromatics were proposed, which suggests that oxidation of hydrocarbon to organic acid is an important process in the aerobic biodegradation of petroleum. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Physicochemical characteristics of PFC surfactants for dry decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Jin; Lee, Chi Woo [Korea University, Seoul (Korea)

    2001-04-01

    Even the trace amount of the used nuclear fuels of high radioactivity are hazardous to the earth and humans. Perfluorocarbons and perfluorocarbon surfactants are emerging to be efficient chemicals in the dry decontamination process of the used fuels of high radioactivity. The theme was undertaken to increase the knowledge on perfluorocarbon surfactants to develop the perfluorocarbon system in the dry decontamination process in Korea. Several cationic and anionic pfc surfactants were synthesized. Effects of pfc surfactants on electrochemical etching of silicon were investigated to form porous silicons. Forces were measured between silicon surfaces and AFM tip in the absence and presence of pfc surfactants. 7 refs., 10 figs. (Author)

  2. Liquid-liquid extraction for surfactant-contaminant separation and surfactant reuse

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, M.A. [Surbec Environmental, Norman, OK (United States); Sabatini, D.A.; Harwell, J.H. [Univ. of Oklahoma, Norman, OK (United States)

    1997-07-01

    Liquid-liquid extraction was investigated for use with surfactant enhanced subsurface remediation. A surfactant liquid-liquid extraction model (SLLEM) was developed for batch equilibrium conditions based on contaminant partitioning between micellar, water, and solvent phases. The accuracy of this fundamental model was corroborated with experimental results (using naphthalene and phenanthrene as contaminants and squalane as the extracting solvent). The SLLEM model was then expanded to nonequilibrium conditions. The effectiveness of this nonequilibrium model was corroborated with experimental results from continuous flow hollow fiber membrane systems. The validated models were used to conduct a sensitivity analysis evaluating the effects of surfactants on the removal of the contaminants in liquid-liquid extraction systems. In addition, liquid-liquid extraction is compared to air stripping for surfactant-contaminant separation. Finally, conclusions are drawn as to the impact of surfactants on liquid-liquid extraction processes, and the significance of these impacts on the optimization of surfactant-enhanced subsurface remediation.

  3. Phase behavior and interfacial tension studies of surfactant systems

    Energy Technology Data Exchange (ETDEWEB)

    Franses, E.I.

    1979-01-01

    Parallel studies of isomerically pure sodium P(1-heptylnonyl) benzene sulfoante, Texas No. 1, its mixture with sodium dodecyl sulfate (SDS), and the petroleum sulfonate TRS 10-80 were made. Phase behavior in water, in decane, and in water-decane mixtures was studied by spectroturbidimetry, polarizing light microscopy, ultracentrifugation, ultrafiltration, densitometry, conductimetry, low-frequency, 0.2 to 20 kHz, dielectric relaxation, isopiestic vapor pressure, and nuclear magnetic resonance spectroscopy. It was deduced that ultralow tensions (less than 0.01 dyn/cm) arise from the dispersed microcrystallites which form a third, usually liquid crystalline, phase at the decane-brine interfacial region. It appears that neither molecular adsorption from solution for micelles have anything to do with ultralow tensions, which appear to be sensitive to the third phase microstructure. The implications of these results for the mechanism of ultralow tensions in surfactant flooding processes for enhanced petroleum recovery are discussed.

  4. Metathesis depolymerization for removable surfactant templates.

    Energy Technology Data Exchange (ETDEWEB)

    Zifer, Thomas (Sandia National Laboratories, Livermore, CA); Wheeler, David Roger; Rahimian, Kamayar; McElhanon, James Ross (Sandia National Laboratories, Livermore, CA); Long, Timothy Michael; Jamison, Gregory Marks; Loy, Douglas Anson (Los Alamos National Laboratories, Los Alamos, NM); Kline, Steven R. (National Institute of Standards and Technology, Gaithersburg, MD); Simmons, Blake Alexander (Sandia National Laboratories, Livermore, CA)

    2005-03-01

    Current methodologies for the production of meso- and nanoporous materials include the use of a surfactant to produce a self-assembled template around which the material is formed. However, post-production surfactant removal often requires centrifugation, calcination, and/or solvent washing which can damage the initially formed material architecture(s). Surfactants that can be disassembled into easily removable fragments following material preparation would minimize processing damage to the material structure, facilitating formation of templated hybrid architectures. Herein, we describe the design and synthesis of novel cationic and anionic surfactants with regularly spaced unsaturation in their hydrophobic hydrocarbon tails and the first application of ring closing metathesis depolymerization to surfactant degradation resulting in the mild, facile decomposition of these new compounds to produce relatively volatile nonsurface active remnants.

  5. Studies on interfacial tension and contact angle of synthesized surfactant and polymeric from castor oil for enhanced oil recovery

    Science.gov (United States)

    Babu, Keshak; Pal, Nilanjan; Bera, Achinta; Saxena, V. K.; Mandal, Ajay

    2015-10-01

    New synthesized polymeric surfactants have immensely attracted the researchers for further development of chemical enhanced oil recovery method particularly in surfactant flooding. Contact angle and interfacial tension measurement tests are the effective ways to identify proper chemicals/surfactants for enhanced oil recovery by chemical/surfactant flooding. In the present study a new polymeric surfactant was synthesized from pre-synthesized sodium methyl ester sulfonate (surfactant) and acrylamide for application in chemical enhanced oil recovery. The synthesized surfactant and polymeric surfactant were used to measure interfacial tension between their aqueous phase and crude oil phase to investigate the efficiency of the surfactants in reduction of interfacial tension. The synthesized polymeric surfactant has also ability to control the mobility because of its viscous nature in aqueous solution. Contact angles of solid-crude oil-surfactant interface were also measured to study the effect of the synthesized surfactant and polymeric surfactant on wettability alteration mechanism. Synergistic effect was studied by using NaCl and synthesized surfactants on interfacial tension. Dynamic interfacial tensions of the surfactant and polymeric surfactant solutions with crude oil were measured at different NaCl concentrations. Interfacial tension was found to be lowered up to 10-2 to 10-3 mN/m which is effective for oil recovery. Measurement of contact angle indicates the wettability change of the quartz surface. Comparative studies on efficiencies of synthesized sodium methyl ester sulfonate surfactant and polymeric surfactant were also carried out with respect to interfacial tension reduction and contact angle change.

  6. Comparing bottom-up and top-down parameterisations of a process-based runoff generation model tailored on floods

    Science.gov (United States)

    Antonetti, Manuel; Scherrer, Simon; Margreth, Michael; Zappa, Massimiliano

    2016-04-01

    Information about the spatial distribution of dominant runoff processes (DRPs) can improve flood predictions on ungauged basins, where conceptual rainfall-runoff models usually appear to be limited due to the need for calibration. For example, hydrological classifications based on DRPs can be used as regionalisation tools assuming that, once a model structure and its parameters have been identified for each DRP, they can be transferred to other areas where the same DRP occurs. Here we present a process-based runoff generation model as an event-based spin-off of the conceptual hydrological model PREVAH. The model is grid-based and consists of a specific storage system for each DRP. To unbind the parameter values from catchment-related characteristics, the runoff concentration and the flood routing are uncoupled from the runoff generation routine and simulated separately. For the model parameterisation, two contrasting approaches are applied. First, in a bottom-up approach, the parameters of the runoff generation routine are determined a priori based on the results of sprinkling experiments on 60-100 m2 hillslope plots at several grassland locations in Switzerland. The model is, then, applied on a small catchment (0.5 km2) on the Swiss Plateau, and the parameters linked to the runoff concentration are calibrated on a single heavy rainfall-runoff event. The whole system is finally verified on several nearby catchments of larger sizes (up to 430 km2) affected by different heavy rainfall events. In a second attempt, following a top-down approach, all the parameters are calibrated on the largest catchment under investigation and successively verified on three sub-catchments. Simulation results from both parameterisation techniques are finally compared with results obtained with the traditional PREVAH.

  7. New type flooding systems in enhanced oil recovery

    Institute of Scientific and Technical Information of China (English)

    Xin Ping Li; Li Yu; Yong Qiang Ji; Bo Wu; Gan Zuo Li; Li Qiang Zheng

    2009-01-01

    Wormlike micelles, obtained in anionic surfactant sodium oleate (NaOA) solutions in the presence of sodium phosphate (Na_3PO_4), were studied using the steady and dynamic rheological methods. The laboratory simulation flooding experiments were used to investigate the effects of flooding for the wormlike micelles system. The results show that the oil recovery is 32.7%. This flooding system is a new type and has high activity with a low cost.

  8. Optimization of Surfactant Mixtures and Their Interfacial Behavior for Advanced Oil Recovery, Annual Report, September 30, 1999-September 30, 2000

    Energy Technology Data Exchange (ETDEWEB)

    Somasundaran, Prof. P.

    2001-04-04

    The goal of this report is to develop improved extraction processes to mobilize and produce the oil left untapped using conventional techniques. Current chemical schemes for recovering the residual oil have been in general less than satisfactory. High cost of the processes as well as significant loss of chemicals by adsorption on reservoir materials and precipitation has limited the utility of chemical-flooding operations. There is a need to develop cost-effective, improved reagent schemes to increase recovery from domestic oil reservoirs. The goal of the report was to develop and evaluate novel mixtures of surfactants for improved oil recovery.

  9. Trypsin from the processing waste of the lane snapper (Lutjanus synagris) and its compatibility with oxidants, surfactants and commercial detergents.

    Science.gov (United States)

    Espósito, Talita S; Marcuschi, Marina; Amaral, Ian P G; Carvalho, Luiz B; Bezerra, Ranilson S

    2010-05-26

    A trypsin from the viscera of the lane snapper (Lutjanus synagris) was purified by heat treatment, fractionation with ammonium sulfate and affinity chromatography. The molecular weight of the enzyme was estimated to be 28.4 kDa (SDS-PAGE). The purified enzyme was capable of hydrolyzing the specific substrate for trypsin benzoyl-arginine-p-nitroanilide (BApNA) and was inhibited by benzamidine and tosyl lysine chloromethyl ketone (TLCK), synthetic trypsin inhibitors and phenylmethylsulfonyl fluoride (PMSF), which is a serine-protease inhibitor. The enzyme exhibited maximal activity at pH 9.0 and 45 degrees C and retained 100% of the activity after incubation at the optimal temperature for 30 min. At a concentration of 10 mM, activity was slightly activated by Ca(2+) and inhibited by the following ions in decreasing order: Cd(2+) > Hg(2+) > Cu(2+) > Zn(2+) > Al(3+). The effects of Ba(2+), K(1+) and Li(1+) proved to be less intensive. Using 1% (w/v) azocasein as substrate, the enzyme revealed high resistance (60% residual activity) when incubated with 10% H(2)O(2) for 75 min. The enzyme retained more than 80% activity after 60 min in the presence of different surfactants (Tween 20, Tween 80 and sodium choleate). The alkaline protease demonstrated compatibility with commercial detergents (7 mg/mL), such as Bem-te-vi, Surf and Ala, retaining more than 50% of initial activity after 60 min at 25 degrees C and 30 min at 40 degrees C. The thermostability and compatibility of this enzyme with commercial detergents suggest a good potentiality for application in the detergent industry.

  10. MINERAL-SURFACTANT INTERACTIONS FOR MINIMUM REAGENTS PRECIPITATION AND ADSORPTION FOR IMPROVED OIL RECOVERY

    Energy Technology Data Exchange (ETDEWEB)

    P. Somasundaran

    2006-04-30

    During this reporting period, further fundamental studies were conducted to understand the mechanism of the interactions between surfactants and minerals with the aim of minimizing chemical loss by adsorption. The effects of pH and mixing ratio on the chemical loss by adsorption were investigated. Some preliminary modeling work has been done towards the aim of developing a guide book to design optimal polymer/surfactant formula based on the understanding of adsorption and orientation of surfactants and their aggregates at solid/liquid interfaces. The study of adsorption of mixed system of n-dodecyl-{beta}-D-maltoside (DM) and dodecyl sulfonate (C{sub 12}SO{sub 3}Na) was continued during this period. Based on the adsorption results, the effects of pH and mixing ratio on reagent loss were quantitatively evaluated. Adsorption of dodecyl maltoside showed a maximum at certain mixing ratio at low pH (3{approx}5), while adsorption of dodecyl maltoside steadily decreased with the increase in C{sub 12}SO{sub 3}Na. Analytical ultracentrifuge technique was employed to study the micellization of DM/C{sub 12}SO{sub 3}Na mixtures. Compositional changes of the aggregates were observed the mixing ratio of the components. Surfactant mixture micellization affects the conformation and orientation of adsorption layer at mineral/water interface and thus the wettability and as a result, the oil release efficiency of the chemical flooding processes. A preliminary term, Reagent Loss Index (RLI), has been proposed to represent the adsorption of all the surfactants in a standardized framework for the development of the models. Previously reported adsorption data have been analyzed using the theoretical framework for the preparation of a guidebook to help optimization of chemical combinations and selection of reagent scheme for enhanced oil recovery.

  11. Development and verification of simplified prediction models for enhanced oil recovery applications. CO/sub 2/ (miscible flood) predictive model. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Paul, G.W.

    1984-10-01

    A screening model for CO/sub 2/ miscible flooding has been developed consisting of a reservoir model for oil rate and recovery and an economic model. The reservoir model includes the effects of viscous fingering, reservoir heterogeneity, gravity segregation and areal sweep. The economic model includes methods to calculate various profitability indices, the windfall profits tax, and provides for CO/sub 2/ recycle. The model is applicable to secondary or tertiary floods, and to solvent slug or WAG processes. The model does not require detailed oil-CO/sub 2/ PVT data for execution, and is limited to five-spot patterns. A pattern schedule may be specified to allow economic calculations for an entire project to be made. Models of similar architecture have been developed for steam drive, in-situ combustion, surfactant-polymer flooding, polymer flooding and waterflooding. 36 references, 41 figures, 4 tables.

  12. Surfactants in tribology

    CERN Document Server

    Biresaw, Girma

    2014-01-01

    Surface science and tribology play very critical roles in many industries. Manufacture and use of almost all consumer and industrial products rely on the application of advanced surface and tribological knowledge. The fourth in a series, Surfactants in Tribology, Volume 4 provides an update on research and development activities connecting surfactants and tribological phenomena. Written by renowned subject matter experts, the book demonstrates how improved design of surfactants can be harnessed to control tribological phenomena. Profusely illustrated and copiously referenced, the chapters also

  13. POLYMERIC SURFACTANT STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    P.M. Saville; J.W. White

    2001-01-01

    Polymeric surfactants are amongst the most widespread of all polymers. In nature, proteins and polysaccharides cause self organization as a result of this surfactancy; in industry, polymeric surfactants play key roles in the food, explosives and surface coatings sectors. The generation of useful nano- and micro-structures in films and emulsions as a result of polymer amphiphilicity and the application of mechanical stress is discussed. The use of X-ray and neutron small angle scattering and reflectivity to measure these structures and their dynamic properties will be described. New results on linear and dendritic polymer surfactants are presented.

  14. Dendrimer-surfactant interactions.

    Science.gov (United States)

    Cheng, Yiyun; Zhao, Libo; Li, Tianfu

    2014-04-28

    In this article, we reviewed the interactions between dendrimers and surfactants with particular focus on the interaction mechanisms and physicochemical properties of the yielding dendrimer-surfactant aggregates. In order to provide insight into the behavior of dendrimers in biological systems, the interactions of dendrimers with bio-surfactants such as phospholipids in bulk solutions, in solid-supported bilayers and at the interface of phases or solid-states were discussed. Applications of the dendrimer-surfactant aggregates as templates to guide the synthesis of nanoparticles and in drug or gene delivery were also mentioned.

  15. Investigating the role of geology in the hydrological response of Mediterranean catchments prone to flash-floods: Regional modelling study and process understanding

    Science.gov (United States)

    Vannier, Olivier; Anquetin, Sandrine; Braud, Isabelle

    2016-10-01

    In this study, a regional distributed hydrological model is used to perform long-term and flash-flood event simulations, over the Cévennes-Vivarais region (south of France). The objective is to improve our understanding on the role played by geology on the hydrological processes of catchments during two past flash-flood events. This modelling work is based on Vannier et al. ("Regional estimation of catchment-scale soil properties by means of streamflow recession analysis for use in distributed hydrological models", Hydrological Processes, 2014), where streamflow recessions are analysed to estimate the thickness and hydraulic conductivity of weathered rock layers, depending on the geological nature of catchments. Weathered rock layers are thus implemented into the hydrological model CVN-p, and the contribution of these layers is assessed during flash-flood events simulations as well as during inter-event periods. The model is used without any calibration, to test hypotheses on the active hydrological processes. The results point out two different hydrological behaviours, depending on the geology: on crystalline rocks (granite and gneiss), the addition of a weathered rock layer considerably improves the simulated discharges, during flash-flood events as well as during recession periods, and makes the model able to remarkably reproduce the observed streamflow dynamics. For other geologies (schists especially), the benefits are real, but not sufficient to properly simulate the observed streamflow dynamics. These results probably underline the existence of poorly known processes (flow paths, non-linear spilling process) associated with the planar structure of schisty rocks. On a methodological point of view, this study proposes a simple way to account for the additional storage associated with each geological entity, through the addition of a weathered porous rock layer situated below the traditionally-considered upper soil horizons, and shows its applicability and

  16. Surfactant Sector Needs Urgent Readjustment

    Institute of Scientific and Technical Information of China (English)

    Huang Hongzhou

    2007-01-01

    @@ Surfactant industrial system has been basically established After 50 years' development, China has already established a surfactant industrial system with a relatively complete product portfolio and can produce 4714 varieties of surfactants in cationic,anionic, nonionic and amphoteric categories.

  17. Distillation Column Flooding Predictor

    Energy Technology Data Exchange (ETDEWEB)

    George E. Dzyacky

    2010-11-23

    /vapor traffic that produce increased contact area and lead to substantial increases in separation efficiency – which translates to a 10% increase in energy efficiency on a BTU/bbl basis. The Flooding Predictor™ operates on the principle that between five to sixty minutes in advance of a flooding event, certain column variables experience an oscillation, a pre-flood pattern. The pattern recognition system of the Flooding Predictor™ utilizes the mathematical first derivative of certain column variables to identify the column’s pre-flood pattern(s). This pattern is a very brief, highly repeatable, simultaneous movement among the derivative values of certain column variables. While all column variables experience negligible random noise generated from the natural frequency of the process, subtle pre-flood patterns are revealed among sub-sets of the derivative values of column variables as the column approaches its hydraulic limit. The sub-set of column variables that comprise the pre-flood pattern is identified empirically through in a two-step process. First, 2ndpoint’s proprietary off-line analysis tool is used to mine historical data for pre-flood patterns. Second, the column is flood-tested to fine-tune the pattern recognition for commissioning. Then the Flooding Predictor™ is implemented as closed-loop advanced control strategy on the plant’s distributed control system (DCS), thus automating control of the column at its hydraulic limit.

  18. Microemulsion-based lycopene extraction: Effect of surfactants, co-surfactants and pretreatments.

    Science.gov (United States)

    Amiri-Rigi, Atefeh; Abbasi, Soleiman

    2016-04-15

    Lycopene is a potent antioxidant that has received extensive attention recently. Due to the challenges encountered with current methods of lycopene extraction using hazardous solvents, industry calls for a greener, safer and more efficient process. The main purpose of present study was application of microemulsion technique to extract lycopene from tomato pomace. In this respect, the effect of eight different surfactants, four different co-surfactants, and ultrasound and enzyme pretreatments on lycopene extraction efficiency was examined. Experimental results revealed that application of combined ultrasound and enzyme pretreatments, saponin as a natural surfactant, and glycerol as a co-surfactant, in the bicontinuous region of microemulsion was the optimal experimental conditions resulting in a microemulsion containing 409.68±0.68 μg/glycopene. The high lycopene concentration achieved, indicates that microemulsion technique, using a low-cost natural surfactant could be promising for a simple and safe separation of lycopene from tomato pomace and possibly from tomato industrial wastes.

  19. Dynamic covalent surfactants

    NARCIS (Netherlands)

    Minkenberg, C.B.

    2012-01-01

    In this thesis the development of surfactant aggregates with fast exchange dynamics between the aggregated and non-aggregated state is described. Dynamic surfactant exchange plays an important role in natural systems, for instance in cell signaling, cell division, and uptake and release of cargo. Re

  20. Morphology control studies of TiO2 microstructures via surfactant-assisted hydrothermal process for dye-sensitized solar cell applications

    Science.gov (United States)

    Lekphet, Woranan; Ke, Tsai-Chyuan; Su, Chaochin; Kathirvel, Sasipriya; Sireesha, Pedaballi; Akula, Suri Babu; Li, Wen-Ren

    2016-09-01

    The controlled morphological TiO2 particles have gained great importance in a wide variety of applications due to their promising physico-chemical properties. In this study, TiO2 microstructures with various shapes to utilize as scattering layer in dye-sensitized solar cell (DSSC) applications were successfully synthesized via different hydrothermal conditions. The effects of the versatile preparation parameters including the amount of titania precursor and surfactant, the addition of ethanol/water, and the hydrothermal process temperature and time on the TiO2 morphology were investigated. The structural and morphological analysis clearly shown that the preparation conditions played crucial roles in the morphology, particle size, and crystalline phase of the TiO2 microparticles. Different kinds of shapes such as rice- (∼1.10 μm (l) and ∼0.41 μm (w)), star- (∼3.60 μm) and flower-like (3.75 μm) TiO2 morphological structures were obtained. The morphology and size of the TiO2 particles were mainly governed by the concentrations of titanium tetraisopropoxide (TTIP) precursor, amounts of tetramethylammonium hydroxide (TMAH) surfactant and hydrothermal temperatures and durations. The as-prepared rice-shaped TiO2 was composed of mixed anatase and brookite binary phases, whereas the star- and flower-shaped TiO2 microstructures were consisted of ternary anatase, rutile, and brookite crystalline TiO2 phases. The three different rice-, star-, and flower-shaped TiO2 microstructures were employed as scattering layers for photoanodes in DSSCs. Among them, the star-like TiO2 photoanode based DSSC exhibited the highest power conversion efficiency of 9.56%, which was also better than those of the devices fabricated without scattering layer (a-TiO2, 8.38%) and with commercial P25 as scattering layer (a-TiO2/P25-TiO2, 8.52%) at the same film thickness of ∼14 μm.

  1. Application of Photo-Fenton Process for COD Removal from Wastewater Produced from Surfactant-Washed  Oil-Contaminated (TPH Soils

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Mehrasbi

    2012-10-01

    Full Text Available Backgrounds and Objectives: The base structure of total petroleum hydrocarbons (TPH is made of hydrogen and carbon. Widespread use, improper disposal and accidental spills of this compounds lead to long term remaining of contaminations such as organic solvents and poly aromatic hydrocarbons (PAHs in the soil and groundwater resources, resulting in critical environmental issues. In this study, an oil-contaminated soil was washed using Tween 80 surfactant and the application of photo-Fenton process (UV/Fe2+/H2O2 for treatment of the produced wastewater was evaluated. Materials and Methods: Tween 80 is a yellow liquid with high viscosity and soluble in water. In order to determine of the photo-Fenton process efficiency, we studied effective variables including Fe concentration, pH, H2O2 concentration, and irradiation time. The UV irradiation source was a medium-pressure mercury vapor lamp (400 w vertically immersed in the solution within 2L volume glass cylindrical reactor.Results: The results showed that efficiency of COD removal depends on the initial Fe concentration, pH, H2O2 concentration and irradiation time. Under optimum conditions, (Fe: 0.1mM, H2O2: 0.43 mM, pH: 3 and UV light irradiation time: 2 hours the removal efficiency of COD was 67.3%. pH plays a crucial role in the photo-Fenton process such that the removal efficiency increased with decreasing of pH. Conclusion: According to the results of this study, under acidic condition, this process is an efficient method for COD removal from the wastewater studied.

  2. Citizen involvement in flood risk governance: flood groups and networks

    Directory of Open Access Journals (Sweden)

    Twigger-Ross Clare

    2016-01-01

    Full Text Available Over the past decade has been a policy shift withinUK flood risk management towards localism with an emphasis on communities taking ownership of flood risk. There is also an increased focus on resilience and, more specifically, on community resilience to flooding. This paper draws on research carried out for UK Department for Environment Food and Rural Affairs to evaluate the Flood Resilience Community Pathfinder (FRCP scheme in England. Resilience is conceptualised as multidimensional and linked to exisiting capacities within a community. Creating resilience to flooding is an ongoing process of adaptation, learning from past events and preparing for future risks. This paper focusses on the development of formal and informal institutions to support improved flood risk management: institutional resilience capacity. It includes new institutions: e.g. flood groups, as well as activities that help to build inter- and intra- institutional resilience capacity e.g. community flood planning. The pathfinder scheme consisted of 13 projects across England led by local authorities aimed at developing community resilience to flood risk between 2013 – 2015. This paper discusses the nature and structure of flood groups, the process of their development, and the extent of their linkages with formal institutions, drawing out the barriers and facilitators to developing institutional resilience at the local level.

  3. Use of nanoparticles to improve the performance of sodium dodecyl sulfate flooding in a sandstone reservoir

    Science.gov (United States)

    Ahmadi, Mohammad Ali

    2016-12-01

    One of the prominent enhanced oil recovery (EOR) methods in oil reservoirs is surfactant flooding. The purpose of this research is to study the effect of nanoparticles on the surfactant adsorption. Real reservoir sandstone rock samples were implemented in adsorption tests. The ranges of the initial surfactant and nano silica concentrations were from 500 to 5000 ppm and 500 ppm to 2000 ppm, respectively. The commercial surfactant used is sodium dodecyl sulfate (SDS) as an ionic surfactant and two different types of nano silica were employed. The rate of surfactant losses extremely depends on the concentration of surfactant in the system, and it was found that the adsorption of surfactant decreased with increasing the concentration of nano silica. Also, it was found that hydrophobic nano silica is more effective than hydrophilic nanoparticles.

  4. Urban RoGeR: Merging process-based high-resolution flash flood model for urban areas with long-term water balance predictions

    Science.gov (United States)

    Weiler, M.

    2016-12-01

    Heavy rain induced flash floods are still a serious hazard and generate high damages in urban areas. In particular in the spatially complex urban areas, the temporal and spatial pattern of runoff generation processes at a wide spatial range during extreme rainfall events need to be predicted including the specific effects of green infrastructure and urban forests. In addition, the initial conditions (soil moisture pattern, water storage of green infrastructure) and the effect of lateral redistribution of water (run-on effects and re-infiltration) have to be included in order realistically predict flash flood generation. We further developed the distributed, process-based model RoGeR (Runoff Generation Research) to include the relevant features and processes in urban areas in order to test the effects of different settings, initial conditions and the lateral redistribution of water on the predicted flood response. The uncalibrated model RoGeR runs at a spatial resolution of 1*1m² (LiDAR, degree of sealing, landuse), soil properties and geology (1:50.000). In addition, different green infrastructures are included into the model as well as the effect of trees on interception and transpiration. A hydraulic model was included into RoGeR to predict surface runoff, water redistribution, and re-infiltration. During rainfall events, RoGeR predicts at 5 min temporal resolution, but the model also simulates evapotranspiration and groundwater recharge during rain-free periods at a longer time step. The model framework was applied to several case studies in Germany where intense rainfall events produced flash floods causing high damage in urban areas and to a long-term research catchment in an urban setting (Vauban, Freiburg), where a variety of green infrastructures dominates the hydrology. Urban-RoGeR allowed us to study the effects of different green infrastructures on reducing the flood peak, but also its effect on the water balance (evapotranspiration and groundwater

  5. Mapping hazards from glacier lake outburst floods based on modelling of process cascades at Lake 513, Carhuaz, Peru

    OpenAIRE

    Schneider, Demian; Huggel, Christian; Cochachin, Alejo; Guillén, Sebastiàn; García, Javier

    2014-01-01

    Recent warming has had enormous impacts on glaciers and high-mountain environments. Hazards have changed or new ones have emerged, including those from glacier lakes that form as glaciers retreat. The Andes of Peru have repeatedly been severely impacted by glacier lake outburst floods in the past. An important recent event occurred in the Cordillera Blanca in 2010 when an ice avalanche impacted a glacier lake and triggered an outburst flood that affected the downstream communities and city of...

  6. Mapping hazards from glacier lake outburst floods based on modelling of process cascades at Lake 513, Carhuaz, Peru

    OpenAIRE

    Schneider, D; C. Huggel; Cochachin, A.; Guillén, S.; García, J.

    2014-01-01

    Recent warming has had enormous impacts on glaciers and high-mountain environments. Hazards have changed or new ones have emerged, including those from glacier lakes that form as glaciers retreat. The Andes of Peru have repeatedly been severely impacted by glacier lake outburst floods in the past. An important recent event occurred in the Cordillera Blanca in 2010 when an ice avalanche impacted a glacier lake and triggered an outburst flood that affected the downstream commu...

  7. k-t acceleration in pure phase encode MRI to monitor dynamic flooding processes in rock core plugs.

    Science.gov (United States)

    Xiao, Dan; Balcom, Bruce J

    2014-06-01

    Monitoring the pore system in sedimentary rocks with MRI when fluids are introduced is very important in the study of petroleum reservoirs and enhanced oil recovery. However, the lengthy acquisition time of each image, with pure phase encode MRI, limits the temporal resolution. Spatiotemporal correlations can be exploited to undersample the k-t space data. The stacked frames/profiles can be well approximated by an image matrix with rank deficiency, which can be recovered by nonlinear nuclear norm minimization. Sparsity of the x-t image can also be exploited for nonlinear reconstruction. In this work the results of a low rank matrix completion technique were compared with k-t sparse compressed sensing. These methods are demonstrated with one dimensional SPRITE imaging of a Bentheimer rock core plug and SESPI imaging of a Berea rock core plug, but can be easily extended to higher dimensionality and/or other pure phase encode measurements. These ideas will enable higher dimensionality pure phase encode MRI studies of dynamic flooding processes in low magnetic field systems.

  8. Evidence for the cooccurrence of nitrite-dependent anaerobic ammonium and methane oxidation processes in a flooded paddy field.

    Science.gov (United States)

    Shen, Li-Dong; Liu, Shuai; Huang, Qian; Lian, Xu; He, Zhan-Fei; Geng, Sha; Jin, Ren-Cun; He, Yun-Feng; Lou, Li-Ping; Xu, Xiang-Yang; Zheng, Ping; Hu, Bao-Lan

    2014-12-01

    Anaerobic ammonium oxidation (anammox) and nitrite-dependent anaerobic methane oxidation (n-damo) are two of the most recent discoveries in the microbial nitrogen cycle. In the present study, we provide direct evidence for the cooccurrence of the anammox and n-damo processes in a flooded paddy field in southeastern China. Stable isotope experiments showed that the potential anammox rates ranged from 5.6 to 22.7 nmol N2 g(-1) (dry weight) day(-1) and the potential n-damo rates varied from 0.2 to 2.1 nmol CO2 g(-1) (dry weight) day(-1) in different layers of soil cores. Quantitative PCR showed that the abundance of anammox bacteria ranged from 1.0 × 10(5) to 2.0 × 10(6) copies g(-1) (dry weight) in different layers of soil cores and the abundance of n-damo bacteria varied from 3.8 × 10(5) to 6.1 × 10(6) copies g(-1) (dry weight). Phylogenetic analyses of the recovered 16S rRNA gene sequences showed that anammox bacteria affiliated with "Candidatus Brocadia" and "Candidatus Kuenenia" and n-damo bacteria related to "Candidatus Methylomirabilis oxyfera" were present in the soil cores. It is estimated that a total loss of 50.7 g N m(-2) per year could be linked to the anammox process, which is at intermediate levels for the nitrogen flux ranges of aerobic ammonium oxidation and denitrification reported in wetland soils. In addition, it is estimated that a total of 0.14 g CH4 m(-2) per year could be oxidized via the n-damo process, while this rate is at the lower end of the aerobic methane oxidation rates reported in wetland soils.

  9. Modeling of the process of heat transfer formation during steam flooding

    Energy Technology Data Exchange (ETDEWEB)

    Malofeev, G.E.; Sheinman, A.B.; Kennavi, F.A.

    1971-01-01

    This work describes experimental data on distribution of temperature in a formation and loss of heat during radial flow of saturated steam. The problem is formulated mathematically and dimensionless parameters characterizing the process are described. The study also throws light on laboratory equipment, experimental techniques and the results obtained. Experimental data are compared with calculated values. The results can be used for evaluating thermal phenomena in high temperature formations in the presence of natural convection and for determining temperature distribution in the case of artificial steam injection. (14 refs.)

  10. [Pulmonary surfactant homeostasis associated genetic abnormalities and lung diseases].

    Science.gov (United States)

    Jiang, Xiaojing; Sun, Xiuzhu; Du, Weihua; Hao, Haisheng; Zhao, Xueming; Wang, Dong; Zhu, Huabin; Liu, Yan

    2016-08-01

    Pulmonary surfactant (PS) is synthesized and secreted by alveolar epithelial type II (AEII) cells, which is a complex compound formed by proteins and lipids. Surfactant participates in a range of physiological processes such as reducing the surface tension, keeping the balance of alveolar fluid, maintaining normal alveolar morphology and conducting host defense. Genetic disorders of the surfactant homeostasis genes may result in lack of surfactant or cytotoxicity, and lead to multiple lung diseases in neonates, children and adults, including neonatal respiratory distress syndrome, interstitial pneumonia, pulmonary alveolar proteinosis, and pulmonary fibrosis. This paper has provided a review for the functions and processes of pulmonary surfactant metabolism, as well as the connection between disorders of surfactant homeostasis genes and lung diseases.

  11. Transient processes associated with the flooding of the Meirama pit lake (La Coruna, Spain); Fenomenos transitorios asociados a la formacion del lago minero de Meirama (La Coruna, Espana)

    Energy Technology Data Exchange (ETDEWEB)

    Delgado Martin, J.; Juncosa Rivera, R.; Gonzalez Philippon, R.; Fernandez Garcia, A.

    2011-07-01

    The Meirama pit lake is a system resulting from the currently ongoing forced flooding of an extensive gray-lignite mine. By comprehensively monitoring a wide variety of physical, chemical and biological parameters we are able to describe the main characteristics of this lake after two years of flooding. This paper focuses upon the description of the thermal structure and stability of this meromitic lake. We have been able to identify thermal and chemical homogenization processes that would have been complete after the first year of flooding but only partially so thereafter (affecting only the surface water to a depth of some 30 metres). Stability calculations support the hypothesis of partial mixing in the shallower water, where the transfer of wind energy may contribute to triggering the mixing phenomenon. The deepest waters of the lake, which are isolated by a halocline resulting from the entrance of denser waters during the firsts months of flooding, would be stable, except for the introduction of external energy, according to the results of the calculations of the Brunt-Vaisala buoyancy frequency. (Author) 22 refs.

  12. 原油组成对碱-表面活性剂-聚合物三元复合驱的影响%Effect of crude oil composition on ternary composite alkali-surfactant-polymer flooding

    Institute of Scientific and Technical Information of China (English)

    孙哲; 孙学法; 卢祥国; 陈欣; 喻琴; 田春雨

    2016-01-01

    The interactions between oil/water samples from different districts in Daqing oilfield with ternary composite alkali-surfactant-polymer(ASP) system were studied. The effects of the crude oil compositions on the crude oil production increment with the ASP system and the properties of the produced fluid were studied. The oil/water samples,extracted active ingredients,raffinate oil and sulfur content in the oil phase were analyzed by means of FTIR,GC-MS and XRF. It was showed that,the characteristic peaks of the active ingredients in the oil/water samples accorded with the features of typical saturated monocarboxylic acids(fatty acids and naphthenic acids). The concentration ofn-alkanes with heavy component in the raffinate oil from the Lamadian oil/water sample was higher,and its composition was closer to that of the surfactant(heavy alkylbenzene sulfonates). It was indicated that,the interfacial tensions between the ASP system and the active ingredients in the oil/water samples or the raffinate oil were high, but there were ultra-low interfacial tensions between the ASP system and the crude oils.%采用大庆油田不同区域油水样与碱-表面活性剂-聚合物(ASP)三元复合体系相互作用,研究了原油组成对三元复合驱增油效果及采出液性质的影响;采用FTIR,GC-MS,XRF等方法对原油油水样、萃取活性组分、萃余油组分及油相中硫元素含量进行表征。表征结果显示,各油水样中的萃取活性组分均具有典型一元饱和羧酸(脂肪酸和环烷酸)峰值特征,喇嘛甸油水样萃余油正构烷烃中的重质组分含量较高,其组成与表面活性剂重烷基苯磺酸盐的组分更接近。实验结果表明,油水样中萃取活性组分及萃余油与三元复合体系间界面张力虽较高,但原油与三元复合体系间却可实现超低界面张力。

  13. Scale-up of miscible flood processes for heterogeneous reservoirs. Second annual report

    Energy Technology Data Exchange (ETDEWEB)

    Orr, F.M. Jr.

    1995-03-01

    Progress is reported for a comprehensive investigation of the scaling behavior of gas injection processes in heterogeneous reservoirs. The interplay of phase behavior, viscous fingering, gravity segregation, capillary imbibition and drainage, and reservoir heterogeneity is examined in a series of simulations and experiments. Use of streamtube to model multiphase flow is demonstrated to be a fast and accurate approach for displacements that are dominated by reservoir heterogeneity. The streamtube technique is particularly powerful for multiphase compositional displacements because it represents the effects of phase behavior with a one-dimensional flow and represents the effects of heterogeneity through the locations of streamtubes. A new approach for fast calculations of critical tie-lines directly from criticality conditions is reported. A global triangular structure solution for four-component flow systems, whose tie-lies meet at the edge of a quaternary phase diagram or lie in planes is presented. Also demonstrated is the extension of this solution to multicomponent systems under the same assumptions. The interplay of gravity, capillary and viscous forces on final residual oil saturation is examined experimentally and theoretically. The analysis of vertical equilibrium conditions for three-phase gravity drainage shows that almost all oil can be recovered from the top part of a reservoir. The prediction of spreading and stability of thin film is performed to investigate three-phase gravity drainage mechanisms. Finally, experimental results from gravity drainage of crude oil in the presence of CO{sub 2} suggest that gravity drainage could be an efficient oil recovery process for vertically fractured reservoirs.

  14. Surfactants in the environment.

    Science.gov (United States)

    Ivanković, Tomislav; Hrenović, Jasna

    2010-03-01

    Surfactants are a diverse group of chemicals that are best known for their wide use in detergents and other cleaning products. After use, residual surfactants are discharged into sewage systems or directly into surface waters, and most of them end up dispersed in different environmental compartments such as soil, water or sediment. The toxic effects of surfactants on various aquatic organisms are well known. In general, surfactants are present in the environment at levels below toxicity and in Croatia below the national limit. Most surfactants are readily biodegradable and their amount is greatly reduced with secondary treatment in wastewater treatment plants. The highest concern is the release of untreated wastewater or wastewater that has undergone primary treatment alone. The discharge of wastewater polluted with massive quantities of surfactants could have serious effects on the ecosystem. Future studies of surfactant toxicities and biodegradation are necessary to withdraw highly toxic and non-biodegradable compounds from commercial use and replace them with more environmentally friendly ones.

  15. Scale-up of miscible flood processes. Quarterly report, July 1, 1993--September 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Orr, F.M. Jr.

    1993-12-31

    Progress is reported for a comprehensive investigation of the scaling behavior of gas injection processes in heterogeneous reservoirs. The interplay of phase behavior, viscous fingering, gravity segregation, capillary imbibition and drainage, and reservoir heterogeneity is examined in a series of simulations and experiments. Compositional and first-contact miscible simulations of viscous fingering and gravity segregation are compared to show that the two techniques can give very different results. Also, analyzed are two-dimensional and three-dimensional flows in which gravity segregation and viscous fingering interact. The simulations show that 2D and 3D flows can differ significantly. A comparison of analytical solutions for three-component two-phase flow with experimental results for oil/water/alcohol systems is reported. While the experiments and theory show reasonable agreement, some differences remain to be explained. The scaling behavior of the interaction of gravity segregation and capillary forces is investigated through simulations and through scaling arguments based on analysis of the differential equations. The simulations show that standard approaches do not agree well with results of low IFT displacements. The scaling analyses, however, reveal flow regimes where capillary, gravity, or viscous forces dominate the flow.

  16. Scale-up of miscible flood processes for heterogeneous reservoirs. 1993 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Orr, F.M. Jr.

    1994-05-01

    Progress is reported for a comprehensive investigation of the scaling behavior of gas injection processes in heterogeneous reservoirs. The interplay of phase behavior, viscous fingering, gravity segregation, capillary imbibition and drainage, and reservoir heterogeneity is examined in a series of simulations and experiments. Compositional and first-contact miscable simulations of viscous fingering and gravity segregation are compared to show that the two techniques can give very different results. Also, analyzed are two-dimensional and three-dimensional flows in which gravity segregation and viscous fingering interact. The simulations show that 2D and 3D flows can differ significantly. A comparison of analytical solutions for three-component two-phase flow with experimental results for oil/water/alcohol systems is reported. While the experiments and theory show reasonable agreement, some differences remain to be explained. The scaling behavior of the interaction of gravity segregation and capillary forces is investigated through simulations and through scaling arguments based on analysis of the differential equations. The simulations show that standard approaches do not agree well with results of low IFT displacements. The scaling analyses, however, reveal flow regimes where capillary, gravity, or viscous forces dominate the flow.

  17. Metathesis depolymerizable surfactants

    Science.gov (United States)

    Jamison, Gregory M.; Wheeler, David R.; Loy, Douglas A.; Simmons, Blake A.; Long, Timothy M.; McElhanon, James R.; Rahimian, Kamyar; Staiger, Chad L.

    2008-04-15

    A class of surfactant molecules whose structure includes regularly spaced unsaturation in the tail group and thus, can be readily decomposed by ring-closing metathesis, and particularly by the action of a transition metal catalyst, to form small molecule products. These small molecules are designed to have increased volatility and/or enhanced solubility as compared to the original surfactant molecule and are thus easily removed by solvent extraction or vacuum extraction at low temperature. By producing easily removable decomposition products, the surfactant molecules become particularly desirable as template structures for preparing meso- and microstructural materials with tailored properties.

  18. Letter to the editor: Generation of self organized critical connectivity network map (SOCCNM) of randomly situated water bodies during flooding process

    OpenAIRE

    B. S. Daya Sagar

    2001-01-01

    This letter presents a brief framework based on nonlinear morphological transformations to generate a self organized critical connectivity network map (SOCCNM) in 2-dimensional space. This simple and elegant framework is implemented on a section that contains a few simulated water bodies to generate SOCCNM. This is based on a postulate that the randomly situated surface water bodies of various sizes and shapes self organize during flooding process.

  19. Letter to the editor: Generation of self organized critical connectivity network map (SOCCNM of randomly situated water bodies during flooding process

    Directory of Open Access Journals (Sweden)

    B. S. Daya Sagar

    2001-01-01

    Full Text Available This letter presents a brief framework based on nonlinear morphological transformations to generate a self organized critical connectivity network map (SOCCNM in 2-dimensional space. This simple and elegant framework is implemented on a section that contains a few simulated water bodies to generate SOCCNM. This is based on a postulate that the randomly situated surface water bodies of various sizes and shapes self organize during flooding process.

  20. Post-translational processing of surfactant protein-C proprotein: targeting motifs in the NH(2)-terminal flanking domain are cleaved in late compartments.

    Science.gov (United States)

    Johnson, A L; Braidotti, P; Pietra, G G; Russo, S J; Kabore, A; Wang, W J; Beers, M F

    2001-03-01

    Rat surfactant protein (SP)-C is a 3.7-kD hydrophobic lung-specific protein generated from proteolytic processing of a 21-kD propeptide (SP-C(21)). We have demonstrated that initial post-translational processing of SP-C(21) involves two cleavages of the COOH-terminus (Beers and colleagues, J. Biol. Chem. 1994;269:20,318--20,328). The goal of the current study was to define processing and function of the NH(2)-terminal flanking domain. Epitope-specific antisera directed against spatially distinct regions of the NH(2) terminus, NPROSP-C(2-9) (epitope = D(2)-L(9)) and NPROSP-C(11-23) (= E(11)-Q(23)) were produced. By Western blotting, both antisera identified SP-C(21) in microsomes. A 6-kD form (SP-C(6)), enriched in lamellar bodies (LBs), was detected only by NPROSP-C(11-23) and not extractable with NaCO(3) treatment. Immunogold staining of ultrathin lung sections with NPROSP-C(11-23) identified proSP-C in both multivesicular bodies (mvb) and LBs whereas NPROSP-C(2-9) labeled only mvb. (35)S-pulse chase analysis demonstrated synthesis of SP-C(21) and three intermediate forms (SP-C(16), SP-C(7), and SP-C(6)). Complete processing involved four separate cleavages with a precursor- product relationship between the low molecular weight forms SP-C(7) and SP-C(6). Fluorescence microscopy of A549 cells expressing fusion proteins of enhanced green fluorescent protein (EGFP) and proSP-C NH(2)-terminal deletion mutants showed targeting of EGFP/SP-C(1-194) and EGFP/SP-C(10-194) to early endosomal antigen-1-negative, CD-63-positive cytoplasmic vesicles whereas EGFP/SP-C(19-194), EGFP/SP-C(Delta 10-18), and EGFP/SP-C(24-194) were restricted to the endoplasmic reticulum (ER). We conclude that synthetic processing includes a previously unrecognized cleavage of the proximal NH(2) terminus (M(1)-L(9)), which occurs after removal of COOH-flanking domains (H(59)-I(194)) but before packaging in LBs, and that the region M(10)-T(18) is required for targeting of proSP-C to post-ER vesicular

  1. Flooding On

    Institute of Scientific and Technical Information of China (English)

    YIN PUMIN

    2010-01-01

    @@ Drenched riverside towns in central and south parts of China were preparing for even worse flooding as water levels in the country's huge rivers surged and rainstorms continued. As of July 27,accumulated precipitation since June 16 in 70 percent of the drainage areas of the Yangtze River had exceeded 50 mm,after three rounds of rainstorms,said Cai Qihua,Deputy Director of the Yangtze River Flood Control and Drought Relief Headquarters.

  2. Phosphine oxide surfactants revisited.

    Science.gov (United States)

    Stubenrauch, Cosima; Preisig, Natalie; Laughlin, Robert G

    2016-04-01

    This review summarizes everything we currently know about the nonionic surfactants alkyl dimethyl (C(n)DMPO) and alkyl diethyl (C(n)DEPO) phosphine oxide (PO surfactants). The review starts with the synthesis and the general properties (Section 2) of these compounds and continues with their interfacial properties (Section 3) such as surface tension, surface rheology, interfacial tension and adsorption at solid surfaces. We discuss studies on thin liquid films and foams stabilized by PO surfactants (Section 4) as well as studies on their self-assembly into lyotropic liquid crystals and microemulsions, respectively (Section 5). We aim at encouraging colleagues from both academia and industry to take on board PO surfactants whenever possible and feasible because of their broad variety of excellent properties.

  3. Dilute Surfactant Methods for Carbonate Formations

    Energy Technology Data Exchange (ETDEWEB)

    Kishore K. Mohanty

    2006-02-01

    There are many fractured carbonate reservoirs in US (and the world) with light oil. Waterflooding is effective in fractured reservoirs, if the formation is water-wet. Many fractured carbonate reservoirs, however, are mixed-wet and recoveries with conventional methods are low (less than 10%). The process of using dilute anionic surfactants in alkaline solutions has been investigated in this work for oil recovery from fractured oil-wet carbonate reservoirs both experimentally and numerically. This process is a surfactant-aided gravity drainage where surfactant diffuses into the matrix, lowers IFT and contact angle, which decrease capillary pressure and increase oil relative permeability enabling gravity to drain the oil up. Anionic surfactants have been identified which at dilute concentration of 0.05 wt% and optimal salinity can lower the interfacial tension and change the wettability of the calcite surface to intermediate/water-wet condition as well or better than the cationic surfactant DTAB with a West Texas crude oil. The force of adhesion in AFM of oil-wet regions changes after anionic surfactant treatment to values similar to those of water-wet regions. The AFM topography images showed that the oil-wetting material was removed from the surface by the anionic surfactant treatment. Adsorption studies indicate that the extent of adsorption for anionic surfactants on calcite minerals decreases with increase in pH and with decrease in salinity. Surfactant adsorption can be minimized in the presence of Na{sub 2}CO{sub 3}. Laboratory-scale surfactant brine imbibition experiments give high oil recovery (20-42% OOIP in 50 days; up to 60% in 200 days) for initially oil-wet cores through wettability alteration and IFT reduction. Small (<10%) initial gas saturation does not affect significantly the rate of oil recovery in the imbibition process, but larger gas saturation decreases the oil recovery rate. As the core permeability decreases, the rate of oil recovery reduces

  4. The Synoptic Model of Widespread Extensive Flash-Flood-Producing Rainstorm Processes in Guangxi%广西大范围致洪暴雨天气模型

    Institute of Scientific and Technical Information of China (English)

    黄香杏; 林开平; 赵江洁

    2001-01-01

    Based on the analysis of spatial and temporal distribution on the flash-flood-producing rainstorm and the features of affecting synoptic systems, the synoptic model of widespread extensive flash-flood-producing rainstorm processes was established and divided into three types, as well. The feature of circle situation and favorable conditions that probably caused the flash-flood-producing rainstorm were given in each type. As a result, the synoptic systems will be useful in forecasting the torrential rainfall processes in the future.%通过致洪暴雨时空分布特点和相应影响天气系统特征的分析,将广西大范围致洪暴雨天气模型分为3个类型,提出各类模型的环流特征、入型条件和致洪暴雨产生的有利条件,为今后制作致洪暴雨预报作出新的尝试。

  5. Flood Risk and Asset Management

    Science.gov (United States)

    2012-09-01

    Within the UK for example, the flooding of the village of Boscastle (August, 2004), that took place over a day, Roca -Collel and Davison (2010), can...Hazard Research Centre. Roca -Collel, M. and Davison, M. (2010). "Two dimensional model analysis of flash- flood processes: application to the Boscastle

  6. Bending elasticity of charged surfactant layers: the effect of mixing.

    Science.gov (United States)

    Bergström, L Magnus

    2006-08-01

    Expressions have been derived from which the spontaneous curvature (H(0)), bending rigidity (k(c)), and saddle-splay constant (k(c)) of mixed monolayers and bilayers may be calculated from molecular and solution properties as well as experimentally available quantities such as the macroscopic hydrophobic-hydrophilic interfacial tension. Three different cases of binary surfactant mixtures have been treated in detail: (i) mixtures of an ionic and a nonionic surfactant, (ii) mixtures of two oppositely charged surfactants, and (iii) mixtures of two ionic surfactants with identical headgroups but different tail volumes. It is demonstrated that k(c)H(0), k(c), and k(c) for mixtures of surfactants with flexible tails may be subdivided into one contribution that is due to bending properties of an infinitely thin surface as calculated from the Poisson-Boltzmann mean field theory and one contribution appearing as a result of the surfactant film having a finite thickness with the surface of charge located somewhat outside the hydrophobic-hydrophilic interface. As a matter of fact, the picture becomes completely different as finite layer thickness effects are taken into account, and as a result, the spontaneous curvature is extensively lowered whereas the bending rigidity is raised. Furthermore, an additional contribution to k(c) is present for surfactant mixtures but is absent for k(c)H(0) and k(c). This contribution appears as a consequence of the minimization of the free energy with respect to the composition of a surfactant layer that is open in the thermodynamic sense and must always be negative (i.e., k(c) is generally found to be brought down by the process of mixing two or more surfactants). The magnitude of the reduction of k(c) increases with increasing asymmetry between two surfactants with respect to headgroup charge number and tail volume. As a consequence, the bending rigidity assumes the lowest values for layers formed in mixtures of two oppositely charged

  7. Prediction of the flooding process at the Ronneburg site - results of an integrated approach; Flutungsprognose am Standort Ronneburg - Ergebnisse eines integrierten Modellansatzes

    Energy Technology Data Exchange (ETDEWEB)

    Paul, M.; Saenger, H.-J.; Snagowski, S. [Wismut GmbH, Chemnitz (Germany); Maerten, H. [UIT Dresden (Germany); Eckart, M. [Geocontrol Gera (Germany)

    1998-12-31

    The flooding process of the Ronneburg uranium mine (WISMUT) was initiated at the turn of the year 1997 to 1998. In order to prepare the flooding process and to derive and optimize technological measures an integrated modelling approach was chosen which includes several coupled modules. The most important issues to be answered are: (1) prediction of the flooding time (2) prediction of the groundwater level at the post-flooding stage, assessment of amount, location and quality of flooding waters entering the receiving streams at the final stage (3) water quality prediction within the mine during the flooding process (4) definition of technological measures and assessment of their efficiency A box model which includes the three-dimensional distribution of the cavity volume in the mine represents the model core. The model considers the various types of dewatered cavity volumes for each mine level / mining field and the degree of vertical and horizontal connection between the mining fields. Different types of open mine space as well as the dewatered geological pore and joint volume are considered taking into account the contour of the depression cone prior to flooding and the characteristics of the different rock types. Based on the mine water balance and the flooding technology the model predicts the rise of the water table over time during the flooding process for each mine field separately. In order to predict the mine water quality and the efficiency of in-situ water treatment the box model was linked to a geochemical model (PHREEQC). A three-dimensional flow model is used to evaluate the post-flooding situation at the Ronneburg site. This model is coupled to the box model. The modelling results of various flooding scenarios show that a prediction of the post-flooding geohydraulic situation is possible despite of uncertainties concerning the input parameters which still exist. The post-flooding water table in the central part of the Ronneburg mine will be 270 m

  8. Don't ignore the elephant in the room: How the intangible concept of place influences the decision-making process for flood resettlement in the Danube catchment

    Science.gov (United States)

    Thaler, Thomas; Seebauer, Sebastian; Babcicky, Philipp

    2017-04-01

    Flood risk management has developed a large inventory of adaptive responses to climate-induced and socio-economic driven hazards. This inventory comprises a wide array of structural and non-structural measures. Yet, one of the most effective responses is planned resettlement of people at risk, were largely ignored as a possible adaptation option towards climate changes in the national flood risk management policies. The study investigates current developments of flood relocation projects and introduces the theoretical concept of place attachment and identity to analyse the challenges when putting flood resettlement initiatives into practice. Two study sites in Austria (Eferdinger Basin and Machland region) illustrate the social and individual dynamics as relocation schemes unfold over time. The relocation scheme is voluntary with the authorities offering to buy out buildings at 80% of their estimated market values, but without compensating for devaluation of the building plot. Legal and administrative processes for executing relocations are well institutionalized. From an engineering standpoint, relocation is the most effective and cost-efficient adaptive response to flood risk in the study areas. However, the measure is socially and politically highly contested. For residents in relocation zones, many profound changes they are confronted with are linked to their place of living, such as iterms of their livelihood, e.g. by no longer passing the family agricultural business to the next generation; in terms of their self-identity, e.g. when tasked to reformulate everyday practices tied to the home left behind; or in terms of rebuilding social networks, e.g. when those who remain have to cope with the thinning out of trusted neighbours. To explore the role of place attachment and identity in individual decision-making, we conducted semi-structured interviews with residents. Our results show that place attachment and identity is a key factor guiding individual

  9. Surfactant-assisted liquefaction of particulate carbonaceous substances

    Science.gov (United States)

    Hsu, G. C. (Inventor)

    1978-01-01

    A slurry of carbonaceous particles such as coal containing an oil soluble polar substituted oleophilic surfactant, suitably an amine substituted long chain hydrocarbon, is liquefied at high temperature and high hydrogen presence. The pressure of surfactant results in an increase in yield and the conversion product contains a higher proportion of light and heavy oils and less asphaltene than products from other liquefaction processes.

  10. Operating Experience of A/O Process for Treatment of Surfactant Production Wastewater%A/O装置处理表面活性剂废水的运行经验

    Institute of Scientific and Technical Information of China (English)

    韩正昌; 黄勇; 王少浦; 蒋雨媚

    2001-01-01

    The process flow of A/O proces for treatment of surfactant production wastewater is introduced,the factors affecting treatment effect are mainly analyzed and the operating mode and control indexes of the process are proposed.Effluent COD is less than 120 mg/L.%介绍了表面活性剂废水处理装置的工艺流程,重点分析了影响A/O装置处理效果的因素,提出了适合该废水处理的运行模式及工艺控制指标,出水COD<120 mg/L.

  11. Drivers of flood damage on event level

    DEFF Research Database (Denmark)

    Kreibich, H.; Aerts, J. C. J. H.; Apel, H.

    2016-01-01

    Flood risk is dynamic and influenced by many processes related to hazard, exposure and vulnerability. Flood damage increased significantly over the past decades, however, resulting overall economic loss per event is an aggregated indicator and it is difficult to attribute causes to this increasing...... trend. Much has been learned about damaging processes during floods at the micro-scale, e.g. building level. However, little is known about the main factors determining the amount of flood damage on event level. Thus, we analyse and compare paired flood events, i.e. consecutive, similar damaging floods...... that occurred in the same area. In analogy to ’Paired catchment studies’ - a well-established method in hydrology to understand how changes in land use affect streamflow – we will investigate how and why resulting flood damage in a region differed between the first and second consecutive flood events. One...

  12. A database on flood and debris-flow processes in alluvial fans: a preliminary analysis aimed at evaluation of the damage

    Science.gov (United States)

    Vennari, Carmela; Santangelo, Nicoletta; Santo, Antonio; Parise, Mario

    2015-04-01

    Debris-flow and flood events cause yearly wide damages to buildings and infrastructures, and produce many casualties and fatalities. These processes are very common in Italy, affecting mainly torrential stream basins with different geological and morphological settings: in the Alpine mountain areas they are quite well analysed, whilst much less attention is generally paid in contexts such as those of the Apennines mostly due to the minor frequency of the events. Nevertheless, debris-flows and flood processes occur along many alluvial fans, have greatly contributed to their building up, and are therefore worth to be studied. Along many areas of the Southern Apennines, coalescent alluvial fans are a widespread geomorphic unit, typically located at the foot of steep slopes. In most cases these areas correspond to the more highly urbanised sectors, generally considered to be safer than the bottom valley, as concerns the direct effects from flooding. During intense storms, villages and towns built on alluvial fans may be affected by flooding and/or debris flow processes originated in the above catchment, and rapidly transferred downslope due to the steep slopes and the torrential character of the streams. This creates a very high hazard to the population and is at the origin of the severe and recurrent damage to urban settlements. Starting from the above considerations, we compiled a catalogue of flood and debris-flow events occurred in Campania Region, southern Italy, by consulting very different information sources: national and local newspapers and journals, regional historical archives, scientific literature, internet blogs. More than 350 events, occurred in Campania from 1700 to present, were collected. Information on time of occurrence and location are available for each event, with different level of accuracy, that is typically lower going back to the oldest events for which only the year or the month of occurrence of the event was identified; nevertheless, for

  13. Combating Floods

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    In summer and autumn of 1998, the river vatleys of the Changjiang, Songhua and Nenjiang rivers were stricken by exceptionally serious floods, As of the, 22nd of August, the flooded areas stretched over 52.4 million acres. More than 223 million people were affected by the flood. 4.97 million houses were ruined, economic losses totaled RMB 166 billion, and most tragically, 3,004 people lost their byes. It was one of the costliest disasters in Chinese history. Millions of People’s Liberation Army soldiers and local people joined hands to battle the floodwaters. Thanks to their unified efforts and tenacious struggle, they successfully withstood the rising, water, resumed production and began to rebuild their homes.

  14. Nanotube Dispersions Made With Charged Surfactant

    Science.gov (United States)

    Kuper, Cynthia; Kuzma, Mike

    2006-01-01

    Dispersions (including monodispersions) of nanotubes in water at relatively high concentrations have been formulated as prototypes of reagents for use in making fibers, films, and membranes based on single-walled carbon nanotubes (SWNTs). Other than water, the ingredients of a dispersion of this type include one or more charged surfactant(s) and carbon nanotubes derived from the HiPco(TradeMark) (or equivalent) process. Among reagents known to be made from HiPco(TradeMark)(or equivalent) SWNTs, these are the most concentrated and are expected to be usable in processing of bulk structures and materials. Test data indicate that small bundles of SWNTs and single SWNTs at concentrations up to 1.1 weight percent have been present in water plus surfactant. This development is expected to contribute to the growth of an industry based on applied carbon nanotechnology. There are expected to be commercial applications in aerospace, avionics, sporting goods, automotive products, biotechnology, and medicine.

  15. COUPLING THE ALKALINE-SURFACTANT-POLYMER TECHNOLOGY AND THE GELATION TECHNOLOGY TO MAXIMIZE OIL PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson

    2004-10-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or more efficient areal sweep efficiency for those with high permeability contrast ''thief zones''. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more oil than waterflooding from swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or those with thief zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. A prior fluid-fluid report discussed interaction of different gel chemical compositions and alkaline-surfactant-polymer solutions. Gel solutions under dynamic conditions of linear corefloods showed similar stability to alkaline-surfactant-polymer solutions as in the fluid-fluid analyses. Aluminum-polyacrylamide, flowing gels are not stable to alkaline-surfactant-polymer solutions of either pH 10.5 or 12.9. Chromium acetate-polyacrylamide flowing and rigid flowing gels are stable to subsequent alkaline-surfactant-polymer solution injection. Rigid flowing chromium acetate-polyacrylamide gels maintained permeability reduction better than flowing chromium acetate-polyacrylamide gels. Silicate-polyacrylamide gels are not stable with subsequent injection of either a pH 10.5 or a 12.9 alkaline-surfactant-polymer solution. Neither aluminum citrate-polyacrylamide nor silicate-polyacrylamide gel systems produced significant incremental oil in linear corefloods. Both flowing and rigid flowing chromium acetate-polyacrylamide gels produced incremental oil with the rigid flowing gel producing the greatest amount. Higher oil recovery could have been due to higher differential pressures across cores. None of

  16. Concept of Flood Risk Map and Its Application

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yuanchang

    2001-01-01

    @@ 1 The concept of flood risk map and its mapping procedure Flood risk management is the process for analysis and assessment of flood risks as well as to form nd implement the disaster mitigation plans. Flood risk analysis is the basic work of flood risk assessment and management that can provide people with the possibilities of flood occurrence and its risk in specific areas and consequently raise the public awareness of flood help to form a reasonable flood prevention plan. However, flood risk mapping is a popular measure adopted by many countries and it provides possible flood areas and water levels as well as possible losses in a friendly way. To form a flood risk map, it is neccessary to allocate the historical information,compute the flood risk and analyze the data.

  17. Summer and Fall Sea Ice Processes in the Amundsen Sea: Bottom melting, surface flooding and snow ice formation

    Science.gov (United States)

    Ackley, S. F.; Perovich, D. K.; Weissling, B.; Elder, B. C.

    2011-12-01

    Two ice mass balance buoys were deployed on the Amundsen Sea, Antarctica, ice pack near January 1, 2011. Below freezing air and snow temperatures and sea ice and seawater temperatures at the freezing point at this time indicated that summer melt had not yet commenced. Over the next two months, however, while snow depths changed by less than 0.1m, ice thickness decreased, from bottom melting, by 0.9-1.0m. As snow temperature records did not show temperatures ever reaching the melting point, no surface melt was recorded during the summer period and the small snow depth changes were presumed to occur by consolidation or wind scouring. Water temperatures above the freezing point caused the observed bottom melting from mid January to late February. During the ice loss periods, progressive flooding by sea water at the base of the snow pack was recorded by temperature sensors, showing an increase in the depth of flooded snow pack of 0.4m by the end of the summer period in late February. We hypothesize that progressive flooding of the surface snow pack gives a mechanism for nutrient replenishment in these upper layers, and continuous high algal growth can therefore occur in the flooded snow layer during summer. An underice radiometer recorded light transmission through the ice and snow at selective wavelengths sensitive to chlorophyll. These radiometric results will be presented to examine this algal growth hypothesis. This flooded layer then refroze from the top down into snow ice as air temperatures dropped during March and April, showing that the layer had refrozen as snow ice on the top surface of the ice. Refreezing of the flooded layer gives an ice growth mechanism at the end of summer of 0.2 m to 0.4m of new ice growth over the majority of the ice pack. The snow ice growth in areas covered with pack ice gives salt fluxes commensurate with new ice growth in the autumn expansion of the ice edge over open water. These high salt fluxes therefore represent a marked

  18. Temporal clustering of floods in Germany: Do flood-rich and flood-poor periods exist?

    Science.gov (United States)

    Merz, Bruno; Nguyen, Viet Dung; Vorogushyn, Sergiy

    2016-10-01

    The repeated occurrence of exceptional floods within a few years, such as the Rhine floods in 1993 and 1995 and the Elbe and Danube floods in 2002 and 2013, suggests that floods in Central Europe may be organized in flood-rich and flood-poor periods. This hypothesis is studied by testing the significance of temporal clustering in flood occurrence (peak-over-threshold) time series for 68 catchments across Germany for the period 1932-2005. To assess the robustness of the results, different methods are used: Firstly, the index of dispersion, which quantifies the departure from a homogeneous Poisson process, is investigated. Further, the time-variation of the flood occurrence rate is derived by non-parametric kernel implementation and the significance of clustering is evaluated via parametric and non-parametric tests. Although the methods give consistent overall results, the specific results differ considerably. Hence, we recommend applying different methods when investigating flood clustering. For flood estimation and risk management, it is of relevance to understand whether clustering changes with flood severity and time scale. To this end, clustering is assessed for different thresholds and time scales. It is found that the majority of catchments show temporal clustering at the 5% significance level for low thresholds and time scales of one to a few years. However, clustering decreases substantially with increasing threshold and time scale. We hypothesize that flood clustering in Germany is mainly caused by catchment memory effects along with intra- to inter-annual climate variability, and that decadal climate variability plays a minor role.

  19. 三次采油中甜菜碱型表面活性剂的研究进展%Research progress of betaine surfactants used in EOR

    Institute of Scientific and Technical Information of China (English)

    张微; 于涛

    2013-01-01

    The research status of the betaine surfactants used in flooding was reviewed simply .The synthesis process was smmarized; The performance of the betaine surfacants was introduced; The application feasibility of betaine surfactants in the enhanced oil recovery was discussed.%简述了驱油用甜菜碱型表面活性剂的研究现状.总结了几类甜菜碱的合成工艺进展;介绍了其在采油技术中的性能研究;探讨了该类表面活性剂在三次采油中应用的可行性.

  20. Modification of nano-sized layered double hydroxides by long-chain organic aliphatic surfactants

    OpenAIRE

    RAMASAMY ANBARASAN; SEUNG SOON IM; WANDUC LEE

    2008-01-01

    The inter-layer anion of layered double hydroxides (LDH) with a hydrotalcite (HT)-like structure was ion-exchanged with various organic surfactants, particularly with long chain aliphatic surfactants. After the ion-exchange process, the basal spacing of the LDH was increased and the increase of the basal spacing depended on various factors, such as the intercalation capacity functionality and orientation capability of the surfactant. Of the employed surfactants, stearic acid intercalated LDH ...

  1. Surfactant-Amino Acid and Surfactant-Surfactant Interactions in Aqueous Medium: a Review.

    Science.gov (United States)

    Malik, Nisar Ahmad

    2015-08-01

    An overview of surfactant-amino acid interactions mainly in aqueous medium has been discussed. Main emphasis has been on the solution thermodynamics and solute-solvent interactions. Almost all available data on the topic has been presented in a lucid and simple way. Conventional surfactants have been discussed as amphiphiles forming micelles and amino acids as additives and their effect on the various physicochemical properties of these conventional surfactants. Surfactant-surfactant interactions in aqueous medium, various mixed surfactant models, are also highlighted to assess their interactions in aqueous medium. Finally, their applied part has been taken into consideration to interpret their possible uses.

  2. Characteristics and properties of a novel in situ method of synthesizing mesoporous TiO{sub 2} nanopowders by a simple coprecipitation process without adding surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Shang-Wei [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 80782, Taiwan (China); Department of Life Science, National University of Kaohsiung, 700 Kaohsiung University Road, Kaohsiung 811, Taiwan (China); Ko, Horng-Huey [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 80782, Taiwan (China); Chiang, Hsiu-Mei [Department of Cosmeceutics, China Medical University, 91 Hsueh-Shih Road, Taichung 40402, Taiwan (China); Chen, Yen-Ling, E-mail: yelichen@kmu.edu.tw [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 80782, Taiwan (China); Lee, Jian-Hong [Clean Energy and Eco-Technology Center, Industrial Technology Research Institute, 8 Gongyan Road, Tainan 734, Taiwan (China); Wen, Chiu-Ming [Department of Life Science, National University of Kaohsiung, 700 Kaohsiung University Road, Kaohsiung 811, Taiwan (China); Wang, Moo-Chin, E-mail: mcwang@kmu.edu.tw [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100 Shih-Chuan 1st Road, Kaohsiung 80782, Taiwan (China)

    2014-11-15

    Highlights: • The TiO{sub 2} precursor powder contained anatase and 19.5% NH{sub 4}Cl. • Mesoporous anatase TiO{sub 2} nanopowders were successfully synthesized. • Uncalcined precursor powder contained the phases of type I NH{sub 4}Cl and anatase TiO{sub 2}. • Anatase size increases from 3.3 to 14.3 nm when calcined at 473–773 K for 2 h. • The average pore size between 3.80 and 14.0 nm when calcined between 473 and 773 K. - Abstract: In situ synthesis of mesoporous TiO{sub 2} nanopowders using titanium tetrachloride (TiCl{sub 4}) and NH{sub 4}OH as initial materials has been successfully fabricated by a coprecipitation process without the addition of surfactant. Characteristics and properties of the mesoporous TiO{sub 2} nanopowders were investigated using differential scanning calorimetry/thermogravimetry (DSC/TG), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and Barrent–Joyner–Halenda (BJH) analyses, transmission electron microscopy (TEM), selected area electron diffraction (SAED) and high resolution TEM (HRTEM). The results of TG and XRD showed that the NH{sub 4}Cl decomposed between 513 and 673 K. XRD results showed that the anatase TiO{sub 2} only contained a single phase when the calcination temperature of the precursor powder was less than 673 K. Whereas phases of anatase and rutile TiO{sub 2} coexist after calcining at 773 K for 2 h. The crystalline size of the anatase and rutile TiO{sub 2} was 14.3 and 26.6 nm, respectively, when the precursor powder was calcined at 773 K for 2 h. The BET and BJH results showed a significant increase in surface area and pore volumes when the NH{sub 4}Cl was completely decomposed. The maximum values of BET specific surface area and volume were 172.8 m{sup 2}/g and 0.392 cm{sup 3}/g, respectively. The average pore sizes when calcination was at 473 and 773 K for 2 h were 3.8 and 14.0 nm, respectively.

  3. Flood Risk and Flood hazard maps - Visualisation of hydrological risks

    Energy Technology Data Exchange (ETDEWEB)

    Spachinger, Karl; Dorner, Wolfgang; Metzka, Rudolf [University of Applied Sciences Deggendorf (Germany); Serrhini, Kamal [Universite de Technologie de Compiegne, Genie des Systemes Urbains, France, and Universite Francois Rabelais, Unite Mixte de Recherche, Tours (France); Fuchs, Sven [Institute of Mountain Risk Engineering, University of Natural Resources and Applied Life Sciences, Vienna (Austria)], E-mail: karl.spachinger@fhd.edu

    2008-11-01

    Hydrological models are an important basis of flood forecasting and early warning systems. They provide significant data on hydrological risks. In combination with other modelling techniques, such as hydrodynamic models, they can be used to assess the extent and impact of hydrological events. The new European Flood Directive forces all member states to evaluate flood risk on a catchment scale, to compile maps of flood hazard and flood risk for prone areas, and to inform on a local level about these risks. Flood hazard and flood risk maps are important tools to communicate flood risk to different target groups. They provide compiled information to relevant public bodies such as water management authorities, municipalities, or civil protection agencies, but also to the broader public. For almost each section of a river basin, run-off and water levels can be defined based on the likelihood of annual recurrence, using a combination of hydrological and hydrodynamic models, supplemented by an analysis of historical records and mappings. In combination with data related to the vulnerability of a region risk maps can be derived. The project RISKCATCH addressed these issues of hydrological risk and vulnerability assessment focusing on the flood risk management process. Flood hazard maps and flood risk maps were compiled for Austrian and German test sites taking into account existing national and international guidelines. These maps were evaluated by eye-tracking using experimental graphic semiology. Sets of small-scale as well as large-scale risk maps were presented to test persons in order to (1) study reading behaviour as well as understanding and (2) deduce the most attractive components that are essential for target-oriented risk communication. A cognitive survey asking for negative and positive aspects and complexity of each single map complemented the experimental graphic semiology. The results indicate how risk maps can be improved to fit the needs of different user

  4. The Effect of Tween® Surfactants in Sol-Gel Processing for the Production of TiO2 Thin Films

    Directory of Open Access Journals (Sweden)

    Ann-Louise Anderson

    2014-12-01

    Full Text Available Titanium dioxide thin films were deposited using a Tween® surfactant modified non-aqueous sol-gel method onto fluorine doped tin oxide glass substrates. The surfactant concentration and type in the sols was varied as well as the number of deposited layers. The as deposited thin films were annealed at 500 °C for 15 min before characterisation and photocatalytic testing with resazurin intelligent ink. The films were characterised using scanning electron microscopy, atomic force microscopy, X-ray diffraction, Raman spectroscopy and UV-Vis spectroscopy. Photocatalytic activity of the films was evaluated using a resazurin dye-ink test and the hydrophilicity of the films was analysed by water-contact angles measurements. Characterisation and photocatalytic testing has shown that the addition of surfactant in varying types and concentrations had a significant effect on the resulting thin film microstructure, such as changing the average particle size from 130 to 25 nm, and increasing the average root mean square roughness from 11 to 350 nm. Such structural changes have resulted in an enhanced photocatalytic performance for the thin films, with an observed reduction in dye half-life from 16.5 to three minutes.

  5. Probabilistic Flood Defence Assessment Tools

    Directory of Open Access Journals (Sweden)

    Slomp Robert

    2016-01-01

    institutions managing flood the defences, and not by just a small number of experts in probabilistic assessment. Therefore, data management and use of software are main issues that have been covered in courses and training in 2016 and 2017. All in all, this is the largest change in the assessment of Dutch flood defences since 1996. In 1996 probabilistic techniques were first introduced to determine hydraulic boundary conditions (water levels and waves (wave height, wave period and direction for different return periods. To simplify the process, the assessment continues to consist of a three-step approach, moving from simple decision rules, to the methods for semi-probabilistic assessment, and finally to a fully probabilistic analysis to compare the strength of flood defences with the hydraulic loads. The formal assessment results are thus mainly based on the fully probabilistic analysis and the ultimate limit state of the strength of a flood defence. For complex flood defences, additional models and software were developed. The current Hydra software suite (for policy analysis, formal flood defence assessment and design will be replaced by the model Ringtoets. New stand-alone software has been developed for revetments, geotechnical analysis and slope stability of the foreshore. Design software and policy analysis software, including the Delta model, will be updated in 2018. A fully probabilistic method results in more precise assessments and more transparency in the process of assessment and reconstruction of flood defences. This is of increasing importance, as large-scale infrastructural projects in a highly urbanized environment are increasingly subject to political and societal pressure to add additional features. For this reason, it is of increasing importance to be able to determine which new feature really adds to flood protection, to quantify how much its adds to the level of flood protection and to evaluate if it is really worthwhile. Please note: The Netherlands

  6. Flooding On

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Drenched riverside towns in central and south parts of China were preparing for even worse flooding aswater levels in the country’s huge rivers surged and rainstorms continued.As of July 27,accumulated precipitation since June 16 in 70 percent of the drainage

  7. Surfactant effects on SF6 hydrate formation.

    Science.gov (United States)

    Lee, Bo Ram; Lee, Ju Dong; Lee, Hyun Ju; Ryu, Young Bok; Lee, Man Sig; Kim, Young Seok; Englezos, Peter; Kim, Myung Hyun; Kim, Yang Do

    2009-03-01

    Sulfur hexafluoride (SF(6)) has been widely used in a variety of industrial processes, but it is one of the most potent greenhouse gases. For this reason, it is necessary to separate or collect it from waste gas streams. One separation method is through hydrate crystal formation. In this study, SF(6) hydrate was formed in aqueous surfactant solutions of 0.00, 0.01, 0.05, 0.15 and 0.20 wt% to investigate the effects of surfactants on the hydrate formation rates. Three surfactants, Tween 20 (Tween), sodium dodecyl sulfate (SDS) and linear alkyl benzene sulfonate (LABS), were tested in a semi-batch stirred vessel at the constant temperature and pressures of 276.2 K and 0.78 MPa, respectively. All surfactants showed kinetic promoter behavior for SF(6) hydrate formation. It was also found that SF(6) hydrate formation proceeded in two stages with the second stage being the most rapid. In situ Raman spectroscopy analysis revealed that the increased gas consumption rate with the addition of surfactant was possibly due to the increased gas filling rate in the hydrate cavity.

  8. The quest for consistent representation of rainfall and realistic simulation of process interactions in flood risk assessment

    Science.gov (United States)

    Efstratiadis, Andreas; Papalexiou, Simon-Michael

    2010-05-01

    We present a methodological framework for the estimation of flood risk in the Boeoticos Kephisos river basin, in Greece, draining an area of 1850 km2. This is a challenging task since the basin has many peculiarities. Due to the dominance of highly-permeable geologic formations, significant portion of runoff derives from karst springs, which rapidly contribute to the streamflow, in contrast to the unusually low contribution of direct (flood) runoff. In addition, due to the combined abstractions from surface and groundwater recourses and the existence of an artificial drainage network in the lower part of the basin (where slopes are noticeably low), the system is heavily modified. To evaluate the probability of extreme floods, especially in such complex basins, it is essential to provide both a statistically consistent description of forcing (precipitation) and a realistic simulation of the runoff mechanisms. Typically, flood modelling is addressed through event-based tools that use deterministic design storms and empirical formulas for the estimation of the "effective" rainfall and its transformation to runoff. Yet, there are several shortcomings in such approaches, especially when employed to large-scale systems. First, the widely-used methodologies for constructing design storms fail to properly represent the variability of rainfall, since they do not account for the temporal and spatial correlations of the historical records. For instance, it is assumed that the input storms to all sub-basins correspond to the same return period. On the other hand, "event-based" models do not allow for interpreting flood risk as joint probabilities of all hydrological variables that interrelate in runoff generation (rainfall, stream-aquifer interactions, soil moisture accounting). Finally, for the estimation of model parameters, the typical approach is to calibrate them against normally few historical flood events, which is at least questionable - the information embedded within

  9. COUPLING THE ALKALINE-SURFACTANT-POLYMER TECHNOLOGY AND THE GELATION TECHNOLOGY TO MAXIMIZE OIL PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qui; Dan Wilson; Phil Dowling

    2004-05-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or more efficient areal sweep efficiency those with high permeability contrast ''thief zones''. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more oil than waterflooding in the swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to the naturally fractured reservoirs or those with thief zones because much of the injected solution bypasses the target pore space containing oil. The objective of this work is to investigate whether combining these two technologies could broaden the applicability of alkaline-surfactant-polymer flooding into these reservoirs. Fluid-fluid interaction with different gel chemical compositions and alkaline-surfactant-polymer solution with pH values ranging from 9.2 to 12.9 have been tested. Aluminum-polyacrylamide gels are not stable to alkaline-surfactant-polymer solutions at any pH. Chromium--polyacrylamide gels with polymer to chromium ion ratios of 25 or greater were stable to alkaline-surfactant-polymer solutions if solution pH was 10.6 or less. When the polymer to chromium ion was 15 or less, chromium-polyacrylamide gels were stable to alkaline-surfactant-polymer solutions with pH values up to 12.9. Chromium-xanthan gum gels were stable to alkaline-surfactant-polymer solutions with pH values of 12.9 at the polymer to chromium ion ratios tested. Silicate-polyacrylamide, resorcinol-formaldehyde, and sulfomethylated resorcinol-formaldehyde gels were also stable to alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Iron-polyacrylamide gels were immediately destroyed when contacted with any of the alkaline-surfactant-polymer solutions with pH values of 9.2 to 12.9.

  10. Surfactant studies for bench-scale operation

    Science.gov (United States)

    Hickey, Gregory S.; Sharma, Pramod K.

    1993-01-01

    A phase 2 study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This report covers the second quarter of work. The major accomplishments were: completion of coal liquefaction autoclave reactor runs with Illinois number 6 coal at processing temperatures of 300, 325, and 350 C, and pressures of 1800 psig; analysis of the filter cake and the filtrate obtained from the treated slurry in each run; and correlation of the coal conversions and the liquid yield quality to the surfactant concentration. An increase in coal conversions and upgrading of the liquid product quality due to surfactant addition was observed for all runs.

  11. Thermodynamics of non-ionic surfactant Triton X-100-cationic surfactants mixtures at the cloud point

    Energy Technology Data Exchange (ETDEWEB)

    Batigoec, Cigdem [Department of Chemistry, Faculty of Sciences, Trakya University, 22030 Edirne (Turkey); Akbas, Halide, E-mail: hakbas34@yahoo.com [Department of Chemistry, Faculty of Sciences, Trakya University, 22030 Edirne (Turkey); Boz, Mesut [Department of Chemistry, Faculty of Sciences, Trakya University, 22030 Edirne (Turkey)

    2011-12-15

    Highlights: > Non-ionic surfactants are used as emulsifier and solubilizate in such as textile, detergent and cosmetic. > Non-ionic surfactants occur phase separation at temperature as named the cloud point in solution. > Dimeric surfactants have attracted increasing attention due to their superior surface activity. > The positive values of {Delta}G{sub cp}{sup 0} indicate that the process proceeds nonspontaneous. - Abstract: This study investigates the effects of gemini and conventional cationic surfactants on the cloud point (CP) of the non-ionic surfactant Triton X-100 (TX-100) in aqueous solutions. Instead of visual observation, a spectrophotometer was used for measurement of the cloud point temperatures. The thermodynamic parameters of these mixtures were calculated at different cationic surfactant concentrations. The gemini surfactants of the alkanediyl-{alpha}-{omega}-bis (alkyldimethylammonium) dibromide type, on the one hand, with different alkyl groups containing m carbon atoms and an ethanediyl spacer, referred to as 'm-2-m' (m = 10, 12, and 16) and, on the other hand, with -C{sub 16} alkyl groups and different spacers containing s carbon atoms, referred to as '16-s-16' (s = 6 and 10) were synthesized, purified and characterized. Additions of the cationic surfactants to the TX-100 solution increased the cloud point temperature of the TX-100 solution. It was accepted that the solubility of non-ionic surfactant containing polyoxyethylene (POE) hydrophilic chain was a maximum at the cloud point so that the thermodynamic parameters were calculated at this temperature. The results showed that the standard Gibbs free energy ({Delta}G{sub cp}{sup 0}), the enthalpy ({Delta}H{sub cp}{sup 0}) and the entropy ({Delta}S{sub cp}{sup 0}) of the clouding phenomenon were found positive in all cases. The standard free energy ({Delta}G{sub cp}{sup 0}) increased with increasing hydrophobic alkyl chain for both gemini and conventional cationic

  12. Mechanistic study of wettability alteration of oil-wet sandstone surface using different surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Bao-feng, E-mail: hbf370283@163.com; Wang, Ye-fei; Huang, Yong

    2015-03-01

    Graphical abstract: Zeta potential of oil-wet quartz powder treated with different surfactants at different concentrations. - Highlights: • Mechanisms of wettability alteration during surfactant flooding were studied. • Different analytical instruments were used to study sandstone wettability alteration. • Surfactants’ structure plays a great role in wettability alteration of solid surface. • CTAB irreversibly desorbs carboxylic acid from solid surface by ionic interaction. • Cationic surfactant is more effective in wettability alteration of sandstone surface. - Abstract: Different analytical methods including Fourier transform infrared (FTIR), atomic force microscopy (AFM), zeta potential measurements, contact angle measurements and spontaneous imbibition tests were utilized to make clear the mechanism for wettability alteration of oil-wet sandstone surface using different surfactants. Results show that among three types of surfactants including cationic surfactants, anionic surfactants and nonionic surfactants, the cationic surfactant CTAB demonstrates the best effect on the wettability alteration of oil-wet sandstone surface. The positively charged head groups of CTAB molecules and carboxylic acid groups from crude oil could interact to form ion pairs, which could be desorbed from the solid surface and solubilized into the micelle formed by CTAB. Thus, the water-wetness of the solid surface is improved. Nonionic surfactant TX-100 could be adsorbed on oil-wet sandstone surface through hydrogen bonds and hydrophobic interaction to alter the wettability of oil-wet solid surface. The wettability alteration of oil-wet sandstone surface using the anionic surfactant POE(1) is caused by hydrophobic interaction. Due to the electrostatic repulsion between the anionic surfactant and the negatively charged surface, POE(1) shows less effect on the wettability alteration of oil-wet sandstone surface.

  13. Flood resilience urban territories. Flood resilience urban territories.

    Science.gov (United States)

    Beraud, Hélène; Barroca, Bruno; Hubert, Gilles

    2010-05-01

    The flood's impact during the last twenty years on French territory reveals our lack of preparation towards large-extended floods which might cause the stopping of companies' activity, services, or lead to housing unavailability during several months. New Orleans' case has to exemplify us: four years after the disaster, the city still couldn't get back its dynamism. In France, more than 300 towns are flood-exposed. While these towns are the mainspring of territory's development, it is likely that the majority of them couldn't get up quickly after a large-extended flood. Therefore, to understand and improve the urban territory's resilience facing floods is a real stake for territory's development. Urban technical networks supply, unify and irrigate all urban territories' constituents. Characterizing their flood resilience can be interesting to understand better urban resilience. In this context, waste management during and after floods is completely crucial. During a flood, the waste management network can become dysfunctional (roads cut, waste storage installations or waste treatment flooded). How can the mayor respect his obligation to guarantee salubrity and security in his city? In post flood the question is even more problematic. The waste management network presents a real stake for territory's restart. After a flood, building materials, lopped-of branches, furniture, business stocks, farm stocks, mud, rubbles, animal cadavers are wet, mixed, even polluted by hydrocarbons or toxic substances. The waste's volume can be significant. Sanitary and environmental risks can be crucial. In view of this situation, waste's management in post crisis period raises a real problem. What to make of this waste? How to collect it? Where to stock it? How to process it? Who is responsible? Answering these questions is all the more strategic since this waste is the mark of disaster. Thus, cleaning will be the first population's and local actor's reflex in order to forget the

  14. Geomorphological factors of flash floods

    Science.gov (United States)

    Kuznetsova, Yulia

    2016-04-01

    Growing anthropogenic load, rise of extreme meteorological events frequency and total precipitation depth often lead to increasing danger of catastrophic fluvial processes worldwide. Flash floods are one of the most dangerous and less understood types of them. Difficulties of their study are mainly related to short duration of single events, remoteness and hard access to origin areas. Most detailed researches of flash floods focus on hydrological parameters of the flow itself and its meteorological factors. At the same time, importance of the basin geological and geomorphological structure for flash floods generation and the role they play in global sediment redistribution is yet poorly understood. However, understanding and quantitative assessment of these features is a real basis for a complete concept of factors, characteristics and dynamics of flash floods. This work is a review of published data on flash floods, and focuses on the geomorphological factors of the phenomenon. We consider both individual roles and interactions between different geomorphological features (the whole basin parameters, characteristics of the single slopes and valley bottom). Special attention is paid to critical values of certain factors. This approach also highlights the gaps or less studied factors of flash floods. Finally, all data is organized into a complex diagram that may be used for flash floods modeling. This also may help to reach a new level of flash flood predictions and risk assessment.

  15. Sizing up surfactant synthesis.

    Science.gov (United States)

    Han, SeungHye; Mallampalli, Rama K

    2014-08-01

    Phosphatidylcholine is generated through de novo synthesis and remodeling involving a lysophospholipid. In this issue of Cell Metabolism, research from the Shimizu lab (Harayama et al., 2014) demonstrates the highly selective enzymatic behavior of lysophospholipid acyltransferases. The authors present an enzymatic model for phosphatidylcholine molecular species diversification that impacts surfactant formation.

  16. Interaction of photosensitive surfactant with DNA and poly acrylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Zakrevskyy, Yuriy, E-mail: yuriy.zakrevskyy@fh-koeln.de; Paasche, Jens; Lomadze, Nino; Santer, Svetlana, E-mail: santer@uni-potsdam.de [Experimental Physics, Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Germany); Cywinski, Piotr; Cywinska, Magdalena; Reich, Oliver; Löhmannsröben, Hans-Gerd [Physical Chemistry, Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Germany)

    2014-01-28

    In this paper, we investigate interactions and phase transitions in polyelectrolyte-surfactant complexes formed between a cationic azobenzene-containing surfactant and two types of polyelectrolytes: natural (DNA) or synthetic (PAA: poly acrylic acid). The construction of a phase diagram allowed distancing between four major phases: extended coil conformation, colloidally stable compacted globules, colloidal instability range, and surfactant-stabilized compact state. Investigation on the complexes’ properties in different phases and under irradiation with UV light provides information about the role of the surfactant's hydrophobic trans isomers both in the formation and destruction of DNA and PAA globules as well as in their colloidal stabilization. The trans isomer shows much stronger affinity to the polyelectrolytes than the hydrophilic cis counterpart. There is no need for complete compensation of the polyelectrolyte charges to reach the complete compaction. On contrary to the findings previously reported in the literature, we demonstrate – for the first time – complete polyelectrolyte compaction which occurs already at 20% of DNA (and at 50% of PAA) charge compensation. The trans isomer plays the main role in the compaction. The aggregation between azobenzene units in the photosensitive surfactant is a driving force of this process. The decompaction can be realized during UV light irradiation and is strongly influenced by the interplay between surfactant-surfactant and surfactant-DNA interactions in the compacted globules.

  17. Interaction of photosensitive surfactant with DNA and poly acrylic acid

    Science.gov (United States)

    Zakrevskyy, Yuriy; Cywinski, Piotr; Cywinska, Magdalena; Paasche, Jens; Lomadze, Nino; Reich, Oliver; Löhmannsröben, Hans-Gerd; Santer, Svetlana

    2014-01-01

    In this paper, we investigate interactions and phase transitions in polyelectrolyte-surfactant complexes formed between a cationic azobenzene-containing surfactant and two types of polyelectrolytes: natural (DNA) or synthetic (PAA: poly acrylic acid). The construction of a phase diagram allowed distancing between four major phases: extended coil conformation, colloidally stable compacted globules, colloidal instability range, and surfactant-stabilized compact state. Investigation on the complexes' properties in different phases and under irradiation with UV light provides information about the role of the surfactant's hydrophobic trans isomers both in the formation and destruction of DNA and PAA globules as well as in their colloidal stabilization. The trans isomer shows much stronger affinity to the polyelectrolytes than the hydrophilic cis counterpart. There is no need for complete compensation of the polyelectrolyte charges to reach the complete compaction. On contrary to the findings previously reported in the literature, we demonstrate - for the first time - complete polyelectrolyte compaction which occurs already at 20% of DNA (and at 50% of PAA) charge compensation. The trans isomer plays the main role in the compaction. The aggregation between azobenzene units in the photosensitive surfactant is a driving force of this process. The decompaction can be realized during UV light irradiation and is strongly influenced by the interplay between surfactant-surfactant and surfactant-DNA interactions in the compacted globules.

  18. Tsunami flooding

    Science.gov (United States)

    Geist, Eric; Jones, Henry; McBride, Mark; Fedors, Randy

    2013-01-01

    Panel 5 focused on tsunami flooding with an emphasis on Probabilistic Tsunami Hazard Analysis (PTHA) as derived from its counterpart, Probabilistic Seismic Hazard Analysis (PSHA) that determines seismic ground-motion hazards. The Panel reviewed current practices in PTHA and determined the viability of extending the analysis to extreme design probabilities (i.e., 10-4 to 10-6). In addition to earthquake sources for tsunamis, PTHA for extreme events necessitates the inclusion of tsunamis generated by submarine landslides, and treatment of the large attendant uncertainty in source characterization and recurrence rates. Tsunamis can be caused by local and distant earthquakes, landslides, volcanism, and asteroid/meteorite impacts. Coastal flooding caused by storm surges and seiches is covered in Panel 7. Tsunamis directly tied to earthquakes, the similarities with (and path forward offered by) the PSHA approach for PTHA, and especially submarine landslide tsunamis were a particular focus of Panel 5.

  19. Improvement of CO sub 2 flood performance

    Energy Technology Data Exchange (ETDEWEB)

    Martin, D.F.; Heller, J.P.

    1991-06-01

    This is the final report of a six-year research project devoted to the study of processes of oil displacement using dense carbon dioxide. The topics studied have included phase behavior and physical properties of mixtures of crude oil with CO{sub 2}, the phenomena involved in the displacement of oil through reservoir rock under oilfield conditions, the influence of stabilized lamella or CO{sub 2}-foam on this displacement and the development of computer programs to simulate the displacement. In addition, the occurrence of nonuniformities in the displacement pattern has also been considered. The effect on displacement of permeability heterogeneities in the reservoir have been studied geostatistically and by direct numerical modelling. Displacement nonuniformities that are induced by viscosity and density differences between displaced and displacing fluids have also been considered, and efforts are described for the development of two different types of additive for purposes of mobility control of CO{sub 2} floods. One of these is the so-called CO{sub 2}-foam, formed by simultaneous flow through the formation of dense CO{sub 2} with a water solution of a special surfactant. The second type under development in the project is known as direct thickener, and consists of a polymer that is soluble in dense CO{sub 2} and able to viscosify it. Significant progress is reported on all of the topics mentioned above. 174 refs., 186 figs., 41 tabs.

  20. Flood inundation extent in storage cell mode

    Institute of Scientific and Technical Information of China (English)

    G.; Farahi; Saeed; Reza; Khodashenas; B.; Ghahraman; K.; Esmaeeli

    2009-01-01

    An understanding of floodplain processes in general and floodplains flooding in particular are vital issues for river engineers and managers. Insufficient observations of flood inundation extent and the infrequent nature of flood inundation necessitate some sort of predictive tools. In this paper flood inundation extent has been simulated by HEC-RAS software in two storage cell and normal modes and capabilities and limitations of the two models have been determined by comparing simulated and observed flood inundation extent which occurred in the study area on Feb 4th, 2004.

  1. Flood inundation extent in storage cell mode

    Institute of Scientific and Technical Information of China (English)

    G.Farahi; Saeed Reza Khodashenas; B.Ghahraman; K.Esmaeeli

    2009-01-01

    An understanding of floodplaln processes In general and floodplains flooding in particular are vital issues for river engineers and managers.Insufficient observations of flood inundation extent and the infrequent nature of flood inundation necessitate some sort of predictive tools.In this paper flood in-undation extent has been simulated by HEC-RAS software in two storage cell and normal modes and capabilities and limitations of the two models have been determined by comparing simulated and ob-served flood inundation extent which occurred in the study area on Feb 4th, 2004.

  2. Floods and climate: emerging perspectives for flood risk assessment and management

    DEFF Research Database (Denmark)

    Merz, B.; Aerts, J.; Arnbjerg-Nielsen, Karsten

    2014-01-01

    Flood estimation and flood management have traditionally been the domain of hydrologists, water resources engineers and statisticians, and disciplinary approaches abound. Dominant views have been shaped; one example is the catchment perspective: floods are formed and influenced by the interaction...... context of floods. We come to the following conclusions: (1) extending the traditional system boundaries (local catchment, recent decades, hydrological/hydraulic processes) opens up exciting possibilities for better understanding and improved tools for flood risk assessment and management. (2) Statistical...... approaches in flood estimation need to be complemented by the search for the causal mechanisms and dominant processes in the atmosphere, catchment and river system that leave their fingerprints on flood characteristics. (3) Natural climate variability leads to time-varying flood characteristics...

  3. The Importance of the Nothofagus Forest on Snowmelt Process linked to floods in Mountain Basins of Tierra del Fuego, Argentina as Input for Land Use Policies.

    Science.gov (United States)

    Iturraspe, R. J.; Urciuolo, A. B.; Lofiego, R.

    2007-05-01

    The conception and application of policies and best practices for the appropriate land use from the view point of extreme floods attenuation, must be based on scientist acknowledge of the basin response, reaching each one of the hydrological cycle's components. That condition is necessary as a start point for an integrated intersectoral management of water and forest resources at the basin scale, especially when forest logging or forest urbanization appear as land use alternatives with socioeconomic importance, confronting the natural roll of the forest in the basin. Within this framework, this article analyzes the forest importance on the seasonal snow-pack and snow-melting process in the mountain basin environment of Tierra del Fuego Island, Argentina, where a mixed rain-snow hydrological regimen and a canopy of native Nothofagus forest are basic features considered. Extreme floods events are related to heavy rain and snow-melting combination. In theory, the worst scenario is the exceptional rain occurrence at the moment of the maximum snow storage, air temperature higher than 0ºC in the whole basin, and previous wet conditions. On this scenario we analyze aspects that indicate forest influences on the snow pack distribution and evolution which are favorable to the attenuation of the intensity of melting process which are induced by rain and temperate air mass. Results were obtained in the context of the EPIC FORCE (EU) Project.

  4. Formation of surfactant-laden drops: comparison of experimental and numerical results

    Science.gov (United States)

    Kovalchuk, Nina; Kahouadji, Lyes; Simmons, Mark; Craster, Richard; Matar, Omar; Juric, Damir; Chergui, Jalel; Shin, Seungwon

    2016-11-01

    Drop formation is ubiquitous in many industrial processes, with surfactants being commonly used to stabilise drops. Thus, understanding the regularities of drop formation and accompanying processes, such as formation of satellite droplets in the presence of surfactant is of high importance. Here we present the results of a comparative experimental and numerical study on formation of surfactant-laden drops over a range of flow rates and surfactant concentrations. The precise parameters of the surface tension isotherm for surfactants used in the experimental study are implemented in the numerical code enabling quantitative comparison between the two approaches. It is shown that the effect of surfactant depends not only on concentration, but also on the value of critical micellar concentration (cmc). The transition to the regime where satellite droplets are no longer released was observed when the flow rate exceeded a threshold value depending on surfactant concentration and cmc value. EPSRC UK Programme Grant MEMPHIS (EP/K003976/1).

  5. Fibrinogen stability under surfactant interaction.

    Science.gov (United States)

    Hassan, Natalia; Barbosa, Leandro R S; Itri, Rosangela; Ruso, Juan M

    2011-10-01

    Differential scanning calorimetry (DSC), circular dichroism (CD), difference spectroscopy (UV-vis), Raman spectroscopy, and small-angle X-ray scattering (SAXS) measurements have been performed in the present work to provide a quantitatively comprehensive physicochemical description of the complexation between bovine fibrinogen and the sodium perfluorooctanoate, sodium octanoate, and sodium dodecanoate in glycine buffer (pH 8.5). It has been found that sodium octanoate and dodecanoate act as fibrinogen destabilizer. Meanwhile, sodium perfluorooctanoate acts as a structure stabilizer at low molar concentration and as a destabilizer at high molar concentration. Fibrinogen's secondary structure is affected by all three studied surfactants (decrease in α-helix and an increase in β-sheet content) to a different extent. DSC and UV-vis revealed the existence of intermediate states in the thermal unfolding process of fibrinogen. In addition, SAXS data analysis showed that pure fibrinogen adopts a paired-dimer structure in solution. Such a structure is unaltered by sodium octanoate and perfluoroctanoate. However, interaction of sodium dodecanoate with the fibrinogen affects the protein conformation leading to a complex formation. Taken together, all results evidence that both surfactant hydrophobicity and tail length mediate the fibrinogen stability upon interaction. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Surfactant therapy in late preterm infants

    Directory of Open Access Journals (Sweden)

    Murat Yurdakök

    2013-06-01

    Full Text Available Late preterm (LPT neonates are at a high risk for respiratory distress soon after birth due to respiratory distress syndrome (RDS, transient tachypnea of the newborn, persistent pulmonary hypertension, and pneumonia along with an increased need for surfactant replacement therapy, continuous positive airway pressure, and ventilator support when compared with the term neonates. In the past, studies on outcomes of infants with respiratory distress have primarily focused on extremely premature infants, leading to a gap in knowledge and understanding of the developmental biology and mechanism of pulmonary diseases in LPT neonates. Surfactant deficiency is the most frequent etiology of RDS in very preterm and moderately preterm infants, while cesarean section and lung infection play major roles in RDS development in LPT infants. The clinical presentation and the response to surfactant therapy in LPT infants may be different than that seen in very preterm infants. Incidence of pneumonia and occurrence of pneumothorax are significantly higher in LPT and term infants. High rates of pneumonia in these infants may result in direct injury to the type II alveolar cells of the lung with decreasing synthesis, release, and processing of surfactant. Increased permeability of the alveolar capillary membrane to both fluid and solutes is known to result in entry of plasma proteins into the alveolar hypophase, further inhibiting the surface properties of surfactant. However, the oxygenation index value do not change dramatically after ventilation or surfactant administration in LPT infants with RDS compared to very preterm infants. These finding may indicate a different pathogenesis of RDS in late preterm and term infants. In conclusion, surfactant therapy may be of significant benefit in LPT infants with serious respiratory failure secondary to a number of insults. However, optimal timing and dose of administration are not so clear in this group. Additional

  7. Surfactant-Assisted Coal Liquefaction

    Science.gov (United States)

    Hickey, Gregory S.; Sharma, Pramod K.

    1993-01-01

    Obtaining liquid fuels from coal which are economically competitive with those obtained from petroleum based sources is a significant challenge for the researcher as well as the chemical industry. Presently, the economics of coal liquefaction are not favorable because of relatively intense processing conditions (temperatures of 430 degrees C and pressures of 2200 psig), use of a costly catalyst, and a low quality product slate of relatively high boiling fractions. The economics could be made more favorable by achieving adequate coal conversions at less intense processing conditions and improving the product slate. A study has been carried out to examine the effect of a surfactant in reducing particle agglomeration and improving hydrodynamics in the coal liquefaction reactor to increase coal conversions...

  8. Assessment of flood peak simulations by Global Hydrological Models

    OpenAIRE

    Miller, James; Kjeldsen, Thomas; Prudhomme, Christel

    2011-01-01

    With significant changes to flood frequency anticipated as a result of climate change it becomes important to investigate how global hydrological models process climate forcing data. Flood frequency distribution describes the relationship between flood peak magnitude and its return period, indicating the average period of time between exceedance of a certain flood magnitude. The steepness of the distribution (or of the growth curve) is a measure of the variability of the flood peak series. An...

  9. Socio-hydrological flood models

    Science.gov (United States)

    Barendrecht, Marlies; Viglione, Alberto; Blöschl, Günter

    2017-04-01

    Long-term feedbacks between humans and floods may lead to complex phenomena such as coping strategies, levee effects, call effects, adaptation effects, and poverty traps. Such phenomena cannot be represented by traditional flood risk approaches that are based on scenarios. Instead, dynamic models of the coupled human-flood interactions are needed. These types of models should include both social and hydrological variables as well as other relevant variables, such as economic, environmental, political or technical, in order to adequately represent the feedbacks and processes that are of importance in human-flood systems. These socio-hydrological models may play an important role in integrated flood risk management by exploring a wider range of possible futures, including unexpected phenomena, than is possible by creating and studying scenarios. New insights might come to light about the long term effects of certain measures on society and the natural system. Here we discuss a dynamic framework for flood risk and review the models that are presented in literature. We propose a way forward for socio-hydrological modelling of the human-flood system.

  10. MICROBIAL SURFACTANTS. I. GLYCOLIPIDS

    Directory of Open Access Journals (Sweden)

    Pirog T. Р.

    2014-02-01

    Full Text Available The review is devoted to surface-active glycolipids. The general characteristics, the physiological role of the rhamnolipids, trehalose lipids, sophorolipids, mannosylerythritol lipids and their traditional producers — the representatives of the genera Pseudozyma, Pseudomonas, Rhodococcus and Candida are given. The detailed analysis of the chemical structure, the stages of the biosynthesis and the regulation of some low molecular glycolipids are done. The own experimental data concerning the synthesis intensification, the physiological role and the practical use of Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii IMV B-7405 surfactants, which are a complex of the glyco-, phospho-, amino- and neutral lipids (glycolipids of all strains are presented by trehalose mycolates are summarized. It was found that R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B-7241 and N. vaccinii IMV B-7405 surfactants have protective, antimicrobial and antiadhesive properties. It was shown that R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B-7241 and N. vaccinii IMV B-7405 surfactants preparation of cultural liquid intensified the degradation of oil in water due to the activation of the natural petroleum-oxidizing microflora.

  11. Surfactants at the Design Limit.

    Science.gov (United States)

    Czajka, Adam; Hazell, Gavin; Eastoe, Julian

    2015-08-04

    This article analyzes how the individual structural elements of surfactant molecules affect surface properties, in particular, the point of reference defined by the limiting surface tension at the aqueous cmc, γcmc. Particular emphasis is given to how the chemical nature and structure of the hydrophobic tails influence γcmc. By comparing the three different classes of surfactants, fluorocarbon, silicone, and hydrocarbon, a generalized surface packing index is introduced which is independent of the chemical nature of the surfactants. This parameter ϕcmc represents the volume fraction of surfactant chain fragments in a surface film at the aqueous cmc. It is shown that ϕcmc is a useful index for understanding the limiting surface tension of surfactants and can be useful for designing new superefficient surfactants.

  12. Floods and climate: emerging perspectives for flood risk assessment and management

    Directory of Open Access Journals (Sweden)

    B. Merz

    2014-02-01

    Full Text Available Flood estimation and flood management have traditionally been the domain of hydrologists, water resources engineers and statisticians, and disciplinary approaches have abound. Dominant views have been shaped; one example is the catchment perspective: floods are formed and influenced by the interaction of local, catchment-specific characteristics, such as meteorology, topography and geology. These traditional views have been beneficial, but they have a narrow framing. In this paper we contrast traditional views with broader perspectives that are emerging from an improved understanding of the climatic context of floods. We conclude: (1 extending the traditional system boundaries (local catchment, recent decades, hydrological/hydraulic processes opens up exciting possibilities for better understanding and improved tools for flood risk assessment and management. (2 Statistical approaches in flood estimation need to be complemented by the search for the causal mechanisms and dominant processes in the atmosphere, catchment and river system that leave their fingerprints on flood characteristic. (3 Natural climate variability leads to time-varying flood characteristics, and this variation may be partially quantifiable and predictable, with the perspective of a dynamic, climate informed flood risk management. (4 Efforts are needed to fully account for factors that contribute to changes in all three risk components (hazard, exposure, vulnerability, and to better understand the interactions between society and floods. (5 Given the global scale and societal importance, we call for the organization of an international multidisciplinary collaboration and data sharing initiative to understand further the links between climate and flooding and to advance flood research.

  13. Effect of surfactants on PAH biodegradation by a bacterial consortium and on the dynamics of the bacterial community during the process.

    Science.gov (United States)

    González, N; Simarro, R; Molina, M C; Bautista, L F; Delgado, L; Villa, J A

    2011-10-01

    The aim of this work was to evaluate the effect of a non-biodegradable (Tergitol NP-10) and a biodegradable (Tween-80) surfactant on growth, degradation rate and microbial dynamics of a polycyclic aromatic hydrocarbon (PAHs) degrading consortium (C2PL05) from a petroleum polluted soil, applying cultivable and non cultivable techniques. Growth and degradation rate were significantly lower with Tergitol NP-10 than that with Tween-80. Toxicity did not show any significant reduction with Tergitol NP-10 whereas with Tween-80 toxicity was almost depleted (30%) after 40 days. Regarding to the cultured bacteria, Pseudomonas and Stenotrophomonas groups were dominant during PAH degradation with Tergitol NP-10, whereas Enterobacter and Stenotrophomonas were dominant with Tween-80. DGGE analyses (PRIMER and MDS) showed that bacteria composition was more similar between treatments when PAHs were consumed than when PAHs concentration was still high. Community changes between treatments were a consequence of Pseudomonas sp., Sphingomonas sp., Sphingobium sp. and Agromonas sp.

  14. Studies on interfacial behavior and wettability change phenomena by ionic and nonionic surfactants in presence of alkalis and salt for enhanced oil recovery

    Science.gov (United States)

    Kumar, Sunil; Mandal, Ajay

    2016-05-01

    Surfactant flooding is one of the most promising method of enhanced oil recovery (EOR) used after the conventional water flooding. The addition of alkali improves the performance of surfactant flooding due to synergistic effect between alkali and surfactant on reduction of interfacial tension (IFT), wettability alteration and emulsification. In the present study the interfacial tension, contact angle, emulsification and emulsion properties of cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS) and polysorbate 80 (Tween 80) surfactants against crude oil have been investigated in presence of sodium chloride (NaCl) and alkalis viz. sodium hydroxide (NaOH), sodium carbonate (Na2CO3), ammonium hydroxide (NH4OH), sodium metaborate (SMB) and diethanolamine (DEA). All three surfactants significantly reduce the IFT values, which are further reduced to ultra-low value (∼10-4 mN/m) by addition of alkalis and salt. It has been found experimentally that alkali-surfactant systems change the wettability of an intermediate-wet quartz rock to water-wet. Emulsification of crude oil by surfactant and alkali has also been investigated in terms of the phase volume and stability of emulsion. A comparative FTIR analysis of crude oil and different emulsions were performed to investigate the interactions between crude oil and displacing water in presence of surfactant and alkali.

  15. Moving liquid surfactant as a way of assessing the properties of surfactant, liquids and surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Titov, A O; Titov, O P; Titov, M O; Karbainov, A N, E-mail: fibrilla45@mail.ru [RUSSIA. GOU VPO East Siberian State Technological University (Russian Federation)

    2011-04-01

    In the study of surface phenomena of the main and only instrumentally-defined parameters are surface tension and wetting angle, including in the field of nanotechnology. These indicators were introduced more than 200 years ago, and any new inventions in this field was no more. The university developed a new method and device for determining the surface activity. The basis of the method and device is the use of video cameras to record the droplet size and changes on the surface of the liquid layer of known thickness from the impact of drops of surfactant (surfactant). Committed changes are then processed using computer software and calculated parameters, which can be characterized by a surfactant and surface properties, which is fluid and very liquid. Determine the surface tension or contact angle is not necessary. Measures of surface activity using the method and device are: 1. The amount of fluid that can move one kilogram of surfactant. The value of this index varies from tens of nanometers to hundreds of thousands of units. The indicator can be converted to energy units, joules. 2. The amount of fluid confined by a surface per unit time is calculated based on the first indicator, complements the characterization of surfactant and may be an indicator of surface characteristics and fluid. 3. Propagation speed of the capillary and microwaves. This indicator complements the first two.

  16. Flood model for Brazil

    Science.gov (United States)

    Palán, Ladislav; Punčochář, Petr

    2017-04-01

    Looking on the impact of flooding from the World-wide perspective, in last 50 years flooding has caused over 460,000 fatalities and caused serious material damage. Combining economic loss from ten costliest flood events (from the same period) returns a loss (in the present value) exceeding 300bn USD. Locally, in Brazil, flood is the most damaging natural peril with alarming increase of events frequencies as 5 out of the 10 biggest flood losses ever recorded have occurred after 2009. The amount of economic and insured losses particularly caused by various flood types was the key driver of the local probabilistic flood model development. Considering the area of Brazil (being 5th biggest country in the World) and the scattered distribution of insured exposure, a domain covered by the model was limited to the entire state of Sao Paolo and 53 additional regions. The model quantifies losses on approx. 90 % of exposure (for regular property lines) of key insurers. Based on detailed exposure analysis, Impact Forecasting has developed this tool using long term local hydrological data series (Agencia Nacional de Aguas) from riverine gauge stations and digital elevation model (Instituto Brasileiro de Geografia e Estatística). To provide most accurate representation of local hydrological behaviour needed for the nature of probabilistic simulation, a hydrological data processing focused on frequency analyses of seasonal peak flows - done by fitting appropriate extreme value statistical distribution and stochastic event set generation consisting of synthetically derived flood events respecting realistic spatial and frequency patterns visible in entire period of hydrological observation. Data were tested for homogeneity, consistency and for any significant breakpoint occurrence in time series so the entire observation or only its subparts were used for further analysis. The realistic spatial patterns of stochastic events are reproduced through the innovative use of d-vine copula

  17. Mitoxantrone-Surfactant Interactions: A Physicochemical Overview

    Directory of Open Access Journals (Sweden)

    Mirela Enache

    2016-10-01

    Full Text Available Mitoxantrone is a synthetic anticancer drug used clinically in the treatment of different types of cancer. It was developed as a doxorubicin analogue in a program to find drugs with improved antitumor activity and decreased cardiotoxicity compared with the anthracyclines. As the cell membrane is the first barrier encountered by anticancer drugs before reaching the DNA sites inside the cells and as surfactant micelles are known as simple model systems for biological membranes, the drugs-surfactant interaction has been the subject of great research interest. Further, quantitative understanding of the interactions of drugs with biomimicking structures like surfactant micelles may provide helpful information for the control of physicochemical properties and bioactivities of encapsulated drugs in order to design better delivery systems with possible biomedical applications. The present review describes the physicochemical aspects of the interactions between the anticancer drug mitoxantrone and different surfactants. Mitoxantrone-micelle binding constants, partitions coefficient of the drug between aqueous and micellar phases and the corresponding Gibbs free energy for the above processes, and the probable location of drug molecules in the micelles are discussed.

  18. Physicochemical treatments of anionic surfactants wastewater: Effect on aerobic biodegradability.

    Science.gov (United States)

    Aloui, Fathi; Kchaou, Sonia; Sayadi, Sami

    2009-05-15

    The effect of different physicochemical treatments on the aerobic biodegradability of an industrial wastewater resulting from a cosmetic industry has been investigated. This industrial wastewater contains 11423 and 3148mgL(-1) of chemical oxygen demand (COD) and anionic surfactants, respectively. The concentration of COD and anionic surfactants were followed throughout the diverse physicochemical treatments and biodegradation experiments. Different pretreatments of this industrial wastewater using chemical flocculation process with lime and aluminium sulphate (alum), and also advanced oxidation process (electro-coagulation (Fe and Al) and electro-Fenton) led to important COD and anionic surfactants removals. The best results were obtained using electro-Fenton process, exceeding 98 and 80% of anionic surfactants and COD removals, respectively. The biological treatment by an isolated strain Citrobacter braakii of the surfactant wastewater, as well as the pretreated wastewater by the various physicochemical processes used in this study showed that the best results were obtained with electro-Fenton pretreated wastewater. The characterization of the treated surfactant wastewater by the integrated process (electro-coagulation or electro-Fenton)-biological showed that it respects Tunisian discharge standards.

  19. Essential Regulation of Lung Surfactant Homeostasis by the Orphan G Protein-Coupled Receptor GPR116

    Directory of Open Access Journals (Sweden)

    Mi Young Yang

    2013-05-01

    Full Text Available GPR116 is an orphan seven-pass transmembrane receptor whose function has been unclear. Global disruption of the Gpr116 gene in mice revealed an unexpected, critical role for this receptor in lung surfactant homeostasis, resulting in progressive accumulation of surfactant lipids and proteins in the alveolar space, labored breathing, and a reduced lifespan. GPR116 expression analysis, bone marrow transplantation studies, and characterization of conditional knockout mice revealed that GPR116 expression in ATII cells is required for maintaining normal surfactant levels. Aberrant packaging of surfactant proteins with lipids in the Gpr116 mutant mice resulted in compromised surfactant structure, function, uptake, and processing. Thus, GPR116 plays an indispensable role in lung surfactant homeostasis with important ramifications for the understanding and treatment of lung surfactant disorders.

  20. Essential Regulation of Lung Surfactant Homeostasis by the Orphan G-protein Coupled Receptor GPR116

    Science.gov (United States)

    Yang, Mi Young; Hilton, Mary Beth; Seaman, Steven; Haines, Diana C.; Nagashima, Kunio; Burks, Christina M.; Tessarollo, Lino; Ivanova, Pavlina T.; Brown, H. Alex; Umstead, Todd M.; Floros, Joanna; Chroneos, Zissis C.; St. Croix, Brad

    2013-01-01

    SUMMARY GPR116 is an orphan seven-pass transmembrane receptor of previously unknown function. Global disruption of the Gpr116 gene in mice revealed an unexpected, critical role for this receptor in lung surfactant homeostasis, resulting in progressive accumulation of surfactant lipids and proteins in the alveolar space, labored breathing, and a reduced lifespan. GPR116 expression analysis, bone marrow transplantation studies and characterization of conditional knockout mice revealed that GPR116 expression in ATII cells is required for maintaining normal surfactant levels. Aberrant packaging of surfactant proteins with lipids in the Gpr116 mutant mice resulted in compromised surfactant structure, function, uptake, and processing. Thus, GPR116 plays an indispensable role in lung surfactant homeostasis with important ramifications for the understanding and treatment of lung surfactant disorders. PMID:23684610

  1. Essential regulation of lung surfactant homeostasis by the orphan G protein-coupled receptor GPR116.

    Science.gov (United States)

    Yang, Mi Young; Hilton, Mary Beth; Seaman, Steven; Haines, Diana C; Nagashima, Kunio; Burks, Christina M; Tessarollo, Lino; Ivanova, Pavlina T; Brown, H Alex; Umstead, Todd M; Floros, Joanna; Chroneos, Zissis C; St Croix, Brad

    2013-05-30

    GPR116 is an orphan seven-pass transmembrane receptor whose function has been unclear. Global disruption of the Gpr116 gene in mice revealed an unexpected, critical role for this receptor in lung surfactant homeostasis, resulting in progressive accumulation of surfactant lipids and proteins in the alveolar space, labored breathing, and a reduced lifespan. GPR116 expression analysis, bone marrow transplantation studies, and characterization of conditional knockout mice revealed that GPR116 expression in ATII cells is required for maintaining normal surfactant levels. Aberrant packaging of surfactant proteins with lipids in the Gpr116 mutant mice resulted in compromised surfactant structure, function, uptake, and processing. Thus, GPR116 plays an indispensable role in lung surfactant homeostasis with important ramifications for the understanding and treatment of lung surfactant disorders. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Drivers of flood damage on event level

    Science.gov (United States)

    Kreibich, Heidi

    2016-04-01

    Flood risk is dynamic and influenced by many processes related to hazard, exposure and vulnerability. Flood damage increased significantly over the past decades, however, resulting overall economic loss per event is an aggregated indicator and it is difficult to attribute causes to this increasing trend. Much has been learned about damaging processes during floods at the micro-scale, e.g. building level. However, little is known about the main factors determining the amount of flood damage on event level. Thus, we analyse and compare paired flood events, i.e. consecutive, similar damaging floods that occurred in the same area. In analogy to 'Paired catchment studies' - a well-established method in hydrology to understand how changes in land use affect streamflow - we will investigate how and why resulting flood damage in a region differed between the first and second consecutive flood events. One example are the 2002 and 2013 floods in the Elbe and Danube catchments in Germany. The 2002 flood caused the highest economic damage (EUR 11600 million) due to a natural hazard event in Germany. Damage was so high due to extreme flood hazard triggered by extreme precipitation and a high number of resulting dyke breaches. Additionally, exposure hotspots like the city of Dresden at the Elbe river as well as some smaller municipalities at the river Mulde (e.g. Grimma, Eilenburg, Bitterfeld, Dessau) were severely impacted. However, affected parties and authorities learned from the extreme flood in 2002, and many governmental flood risk programs and initiatives were launched. Considerable improvements since 2002 occurred on many levels that deal with flood risk reduction and disaster response, in particular in 1) increased flood prevention by improved spatial planning, 2) an increased number of property-level mitigation measures, 3) more effective early warning and improved coordination of disaster response and 4) a more targeted maintenance of flood defence systems and their

  3. BINDING ISOTHERMS SURFACTANT-PROTEINS

    Directory of Open Access Journals (Sweden)

    Elena Irina Moater

    2011-12-01

    Full Text Available The interactions between surfactants and proteins shows some similarities with interactions between surfactants and polymers, but the hydrophobic amphoteric nature of proteins and their secondary and tertiary structure components make them different from conventional polymer systems. Many studies from the past about surfactant - proteins bonding used the dialysis techniques. Other techniques used to determine the binding isotherm, included ultrafiltration, ultracentrifugation, potentiometry, ion-selective electrode method and surface tension. High affinity isotherms which are typical of an anionic surfactant - protein bonding, exhibit an initial increase steep followed by a slow growth region and then a vertical growth above a certain concentration. This isotherm is typical of ionic surfactant to protein binding. Often the high affinity initial bond appears at very low concentrations of surfactant and therefore in some protein-surfactant systems, the exact shape of the isotherm in this region may be missing. The surfactant - protein binding is influenced by a number of variables such as the nature and chain length of surfactant, pH, ionic strength, temperature, nature of this protein and additives.

  4. Implementing the EU Floods Directive (2007/60/EC) in Austria: Flood Risk Management Plans

    Science.gov (United States)

    Neuhold, Clemens

    2013-04-01

    he Directive 2007/60/EC of the European Parliament and of the Council of 23 October 2007 on the assessment and management of flood risks (EFD) aims at the reduction of the adverse consequences for human health, the environment, cultural heritage and economic activity associated with floods in the Community. This task is to be achieved based on three process steps (1) preliminary flood risk assessment (finalised by the end of 2011), (2) flood hazard maps and flood risk maps (due 2013) and (3) flood risk management plans (due 2015). Currently, an interdisciplinary national working group is defining the methodological framework for flood risk management plans in Austria supported by a constant exchange with international bodies and experts. Referring to the EFD the components of the flood risk management plan are (excerpt): 1. conclusions of the preliminary flood risk assessment 2. flood hazard maps and flood risk maps and the conclusions that can be drawn from those maps 3. a description of the appropriate objectives of flood risk management 4. a summary of measures and their prioritisation aiming to achieve the appropriate objectives of flood risk management The poster refers to some of the major challenges in this process, such as the legal provisions, coordination of administrative units, definition of public relations, etc. The implementation of the EFD requires the harmonisation of legal instruments of various disciplines (e.g. water management, spatial planning, civil protection) enabling a coordinated - and ideally binding - practice of flood risk management. This process is highly influenced by the administrative organisation in Austria - federal, provincial and municipality level. The Austrian approach meets this organisational framework by structuring the development of the flood risk management plan into 3 time-steps: (a) federal blueprint, (b) provincial editing and (c) federal finishing as well as reporting to the European Commission. Each time

  5. The effect of surfactant on pollutant biosorption of Trametes versicolor

    Science.gov (United States)

    Gül, Ülküye Dudu; Silah, Hülya; Akbaş, Halide; Has, Merve

    2016-04-01

    The major problem concerning industrial wastewater is treatment of dye and heavy metal containing effluents. Industrial effluents are also contained surfactants that are used as levelling, dispersing and wetting agents. The purpose of this study was to investigate the effect of surfactant on textile dye biosorption properties of a white rot fungus named Trametes versicolor. Reactive dyes are commonly used in textile industry because of their advantages such as brightness and excellent color fastness. A recative textile dye, called Everzol Black, was used in this study. The low-cost mollasses medium is used for fungal growth. The usage of mollases, the sugar refinery effluent as a source of energy and nutrients, gained importance because of reducing the cost and also reusing another waste. In biosorption process the effect of surfactant on dye removal properties of T. versicolor was examined as a function of pH, dye consentration and surfactant concentration. The results of this study showed that the surfactant enhanced the dye removal capacity of Trametes versicolor. The dye and surfactant molecules were interacted electrostatically and these electrostatic interactions improved dye removal properties of filamentous fungus T. versicolor. The results of this study recommended the use of surfactants as an inducer in textile wastewater treatment technologies.

  6. Sorptive affinity of ionic surfactants on silt loamy soil

    Directory of Open Access Journals (Sweden)

    Xingchao Qi

    2016-10-01

    Full Text Available Due to their broad applications, ionic surfactants have already been released into or utilized in soil and environmental systems. However, current understanding on the sorption behavior of surfactants onto soils is still limited. This work systematically investigated the sorption kinetics and isotherms of one cationic surfactant, cetyltrimethylammonium bromide (CTAB, and one anionic surfactant, sodium dodecyl sulfate (SDS, onto a silt loamy soil to determine the governing sorption mechanisms. The pseudo-second-order rate equation described the sorption kinetics data better than the pseudo-first-order rate equation. Experimental data showed that the sorption equilibrium for CTAB and SDS were reached at 24 and 240 h, respectively. Langmuir equation was better than Freundlich equation in simulating the sorption isotherms of CTAB and SDS on the soil. Soil Langmuir maximum sorption capacity of CTAB was much higher than that to SDS. When the experimental temperature increased, the sorption of CTAB and SDS on the soil decreased. In addition, the sorptive process of the surfactants on the soil was spontaneous and exothermal, as indicated by the absolute values of Gibbs free energy and enthalpy. The results also indicated that physical sorption was the dominant mechanism for the sorption of the two surfactants on the soil. Findings from this work are crucial to understand the environmental behaviors of ionic surfactants.

  7. FLOODING ATTACK AWARE SECURE AODV

    Directory of Open Access Journals (Sweden)

    S. Madhavi

    2013-01-01

    Full Text Available Providing security in a Mobile Ad hoc Network (MANET is a challenging task due to its inherent nature. Flooding is a type of Denial of Service (DoS attack in MANET. Intentional flooding may lead to disturbances in the networking operation. This kind of attack consumes battery power, storage space and bandwidth. Flooding the excessive number of packets may degrade the performance of the network. This study considers hello flooding attack. As the hello packets are continuously flooded by the malicious node, the neighbor node is not able to process other packets. The functioning of the legitimate node is diverted and destroys the networking operation. Absence of hello packet during the periodical hello interval may lead to wrong assumption that the neighbor node has moved away. So one of the intermediate neighbor nodes sends Route Error (RERR message and the source node reinitiates the route discovery process. In a random fashion the hello interval values are changed and convey this information to other nodes in the network in a secured manner. This study identifies and prevents the flooding attack. This methodology considers the performance parameters such as packet delivery ratio, delay and throughput. This algorithm is implemented in Secure AODV and tested in ad hoc environment. The result of the proposed algorithm decreases the control overhead by 2%.

  8. Scales of Natural Flood Management

    Science.gov (United States)

    Nicholson, Alex; Quinn, Paul; Owen, Gareth; Hetherington, David; Piedra Lara, Miguel; O'Donnell, Greg

    2016-04-01

    The scientific field of Natural flood Management (NFM) is receiving much attention and is now widely seen as a valid solution to sustainably manage flood risk whilst offering significant multiple benefits. However, few examples exist looking at NFM on a large scale (>10km2). Well-implemented NFM has the effect of restoring more natural catchment hydrological and sedimentological processes, which in turn can have significant flood risk and WFD benefits for catchment waterbodies. These catchment scale improvements in-turn allow more 'natural' processes to be returned to rivers and streams, creating a more resilient system. Although certain NFM interventions may appear distant and disconnected from main stem waterbodies, they will undoubtedly be contributing to WFD at the catchment waterbody scale. This paper offers examples of NFM, and explains how they can be maximised through practical design across many scales (from feature up to the whole catchment). New tools to assist in the selection of measures and their location, and to appreciate firstly, the flooding benefit at the local catchment scale and then show a Flood Impact Model that can best reflect the impacts of local changes further downstream. The tools will be discussed in the context of our most recent experiences on NFM projects including river catchments in the north east of England and in Scotland. This work has encouraged a more integrated approach to flood management planning that can use both traditional and novel NFM strategies in an effective and convincing way.

  9. Interaction of nonionic surfactant AEO9 with ionic surfactants

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-guo; YIN Hong

    2005-01-01

    The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammonium bromide (CTAB) at molar fraction of AEO9, αAEO9 =0.5. The surface properties of the surfactants, critical micelle concentration (CMC),effectiveness of surface tension reduction (γCMC), maximum surface excess concentration (Гmax) and minimum area per molecule at the air/solution interface (Amin) were determined for both individual surfactants and their mixtures. The significant deviations from ideal behavior (attractive interactions) of the nonionic/ionic surfactant mixtures were determined. Mixtures of both AEO9/SDS and AEO9/CTAB exhibited synergism in surface tension reduction efficiency and mixed micelle formation, but neither exhibited synergism in surface tension reduction effectiveness.

  10. Adsorption of surfactants and polymers at interfaces

    Science.gov (United States)

    Rojas, Orlando Jose

    Surface tension and high-resolution laser light scattering experiments were used to investigate the adsorption of isomeric sugar-based surfactants at the air/liquid interface in terms of surfactant surface packing and rheology. Soluble monolayers of submicellar surfactant solutions exhibited a relatively viscous behavior. It was also proved that light scattering of high-frequency thermally-induced capillary waves can be utilized to study surfactant exchange between the surface and the bulk solution. Such analysis revealed the existence of a diffusional relaxation mechanism. A procedure based on XPS was developed for quantification, on an absolute basis, of polymer adsorption on mica and Langmuir-Blodgett cellulose films. The adsorption of cationic polyelectrolytes on negatively-charged solid surfaces was highly dependent on the polymer ionicity. It was found that the adsorption process is driven by electrostatic mechanisms. Charge overcompensation (or charge reversal) of mica occurred after adsorption of polyelectrolytes of ca. 50% charge density, or higher. It was demonstrated that low-charge-density polyelectrolytes adsorb on solid surfaces with an extended configuration dominated by loops and tails. In this case the extent of adsorption is limited by steric constraints. The conformation of the polyelectrolyte in the adsorbed layer is dramatically affected by the presence of salts or surfactants in aqueous solution. The phenomena which occur upon increasing the ionic strength are consistent with the screening of the electrostatic attraction between polyelectrolyte segments and solid surface. This situation leads to polyelectrolyte desorption accompanied by both an increase in the layer thickness and the range of the steric force. Adsorbed polyelectrolytes and oppositely charged surfactants readily associate at the solid/liquid interface. Such association induces polyelectrolyte desorption at a surfactant concentration which depends on the polyelectrolyte charge

  11. What are the hydro-meteorological controls on flood characteristics?

    Science.gov (United States)

    Nied, Manuela; Schröter, Kai; Lüdtke, Stefan; Nguyen, Viet Dung; Merz, Bruno

    2017-02-01

    Flood events can be expressed by a variety of characteristics such as flood magnitude and extent, event duration or incurred loss. Flood estimation and management may benefit from understanding how the different flood characteristics relate to the hydrological catchment conditions preceding the event and to the meteorological conditions throughout the event. In this study, we therefore propose a methodology to investigate the hydro-meteorological controls on different flood characteristics, based on the simulation of the complete flood risk chain from the flood triggering precipitation event, through runoff generation in the catchment, flood routing and possible inundation in the river system and floodplains to flood loss. Conditional cumulative distribution functions and regression tree analysis delineate the seasonal varying flood processes and indicate that the effect of the hydrological pre-conditions, i.e. soil moisture patterns, and of the meteorological conditions, i.e. weather patterns, depends on the considered flood characteristic. The methodology is exemplified for the Elbe catchment. In this catchment, the length of the build-up period, the event duration and the number of gauges undergoing at least a 10-year flood are governed by weather patterns. The affected length and the number of gauges undergoing at least a 2-year flood are however governed by soil moisture patterns. In case of flood severity and loss, the controlling factor is less pronounced. Severity is slightly governed by soil moisture patterns whereas loss is slightly governed by weather patterns. The study highlights that flood magnitude and extent arise from different flood generation processes and concludes that soil moisture patterns as well as weather patterns are not only beneficial to inform on possible flood occurrence but also on the involved flood processes and resulting flood characteristics.

  12. Green Cosmetic Surfactant from Rice: Characterization and Application

    OpenAIRE

    Ibrahim Hanno; Marisanna Centini; Cecilia Anselmi; Claudia Bibiani

    2015-01-01

    During recent years, microwave irradiation has been extensively used for performing green organic synthesis. The aim of this study was to synthesize, through a microwave-assisted irradiation process, a natural surfactant with O/W emulsifying properties. Our attention was focused on polyglycerol esters of fatty acids that are biocompatible and biodegradable non-ionic surfactants widely used in food and cosmetic products. The emulsifier was obtained using vegetable raw material from renewable s...

  13. Interaction of Natural Dye (Allium cepa) with Ionic Surfactants

    OpenAIRE

    2013-01-01

    Allium cepa is a natural dye that has been extracted from onion skin with the help of soxhlet apparatus. The pigment in the dye pelargonidin was found to be 2.25%. The interaction of the dye with ionic surfactants, namely, cationic surfactant (cetyltrimethylammonium bromide) and anionic (sodium lauryl sulphate) has been studied by spectrophotometrically, conductivity, and surface tension measurements. The thermodynamic and surface parameters have been evaluated for the interaction process. Th...

  14. Enhanced oil recovery by surfactant-enhanced volumetric sweep efficiency: First annual report for the period September 30, 1985-September 30, 1986. [Sandpacks

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, J H; Scamehorn, J F

    1987-05-01

    Surfactant-enhanced volumetric sweep efficiency is a novel EOR method which utilizes precipitation/coacervation of surfactants to plug the most permeable regions of the reservoir, improving the efficiency of a waterflooding operation. This technique does not rely on reduction of interfacial tension between aqueous and oleic phases to enhance oil recovery. Therefore, even though surfactants are involved, this new technique is not a substitute or improvement on classical surfactant flooding; however, it has the potantial to compete with polymer flooding as an alternative sweep efficiency improvement method. In surfactant-enhanced volumetric sweep efficiency, a slug containing one kind of surfactant is injected into the reservoir, followed by a brine spacer. This is followed by injection of a second kind of surfactant which has lower adsorption than the first surfactant used. Anionic and cationic surfactants are one possible combination for this application. These may form either a precipitate or a coacervate upon mixing. Phase boundaries for some specific systems of this type have been determined over a wide range of conditions and a model developed to describe this behavior. Another possibility is the use of nonionic surfactants, which may form coacervate under proper conditions. The adsorption behavior of mixtures of anionic and nonionic surfactants was measured to aid in modeling the chromatographic effects with these surfactants in the reservoir. Studies with sandpacks of different permeabilities in parallel configuration using mixtures of anionic and cationic surfactants have demonstrated the capability of this method to reduce flow rates through a more permeable sandpack more than that through a less permeable sandpack. 4 refs., 23 figs., 8 tabs.

  15. Gemini ester quat surfactants and their biological activity.

    Science.gov (United States)

    Łuczyński, Jacek; Frąckowiak, Renata; Włoch, Aleksandra; Kleszczyńska, Halina; Witek, Stanisław

    2013-03-01

    Cationic gemini surfactants are an important class of surface-active compounds that exhibit much higher surface activity than their monomeric counterparts. This type of compound architecture lends itself to the compound being easily adsorbed at interfaces and interacting with the cellular membranes of microorganisms. Conventional cationic surfactants have high chemical stability but poor chemical and biological degradability. One of the main approaches to the design of readily biodegradable and environmentally friendly surfactants involves inserting a bond with limited stability into the surfactant molecule to give a cleavable surfactant. The best-known example of such a compound is the family of ester quats, which are cationic surfactants with a labile ester bond inserted into the molecule. As part of this study, a series of gemini ester quat surfactants were synthesized and assayed for their biological activity. Their hemolytic activity and changes in the fluidity and packing order of the lipid polar heads were used as the measures of their biological activity. A clear correlation between the hemolytic activity of the tested compounds and their alkyl chain length was established. It was found that the compounds with a long hydrocarbon chain showed higher activity. Moreover, the compounds with greater spacing between their alkyl chains were more active. This proves that they incorporate more easily into the lipid bilayer of the erythrocyte membrane and affect its properties to a greater extent. A better understanding of the process of cell lysis by surfactants and of their biological activity may assist in developing surfactants with enhanced selectivity and in widening their range of application.

  16. 镀膜工艺对复配十八烷胺膜层抗腐蚀性能的影响%Influence on Coating Process on Corrosion Resistance of Octadecylamine Coating with Surfactant Mixture

    Institute of Scientific and Technical Information of China (English)

    刘俊英; 危晴; 吴志明; 曲敬信

    2011-01-01

    The influences of the coating process on the the corrosion resistance of octadecylamine corrosion inhibitor with surfactant mixture were studied, and the corrosion mechanism of the coatings was analyzed. The main results show that the microscopic defects of the coating are corroded when the coating solution pH=6, and the corrosion is corroded on the grain boundary of the coating when the coating solution pH=8~12. The coating's structure is integrity and the corrosion resistance increases with the increase of coating solution pH. The corrosion resistance of the coating enhances and its microstructure becomes dense with the increase of temperature. The best coating process of the octadecylamine corrosion inhibitor with surfactant mixture is coating solution pH=10 and coating temperature 250 °C.%研究了镀膜工艺对复配十八烷胺缓蚀剂膜层抗腐蚀性能影响,并分析了膜层的腐蚀机理.结果表明,镀膜液pH=6的膜层腐蚀发生在微观缺陷上,pH=8~12的膜层腐蚀发生在晶界上;随着镀膜液pH值升高,膜层结构完整,抗腐蚀性能增强;在镀膜液pH=8~12时,随镀膜温度升高,膜层的组织致密,抗腐蚀性能增强.镀膜液pH=10、镀膜温度250℃为复配十八烷胺缓蚀剂最佳镀膜工艺.

  17. Surfactant monitoring by foam generation

    Science.gov (United States)

    Mullen, Ken I.

    1997-01-01

    A device for monitoring the presence or absence of active surfactant or other surface active agents in a solution or flowing stream based on the formation of foam or bubbles is presented. The device detects the formation of foam with a light beam or conductivity measurement. The height or density of the foam can be correlated to the concentration of the active surfactant present.

  18. Flooding and Schools

    Science.gov (United States)

    National Clearinghouse for Educational Facilities, 2011

    2011-01-01

    According to the Federal Emergency Management Agency, flooding is the nation's most common natural disaster. Some floods develop slowly during an extended period of rain or in a warming trend following a heavy snow. Flash floods can occur quickly, without any visible sign of rain. Catastrophic floods are associated with burst dams and levees,…

  19. A systems approach to mapping transcriptional networks controlling surfactant homeostasis

    Directory of Open Access Journals (Sweden)

    Dave Vrushank

    2010-07-01

    Full Text Available Abstract Background Pulmonary surfactant is required for lung function at birth and throughout life. Lung lipid and surfactant homeostasis requires regulation among multi-tiered processes, coordinating the synthesis of surfactant proteins and lipids, their assembly, trafficking, and storage in type II cells of the lung. The mechanisms regulating these interrelated processes are largely unknown. Results We integrated mRNA microarray data with array independent knowledge using Gene Ontology (GO similarity analysis, promoter motif searching, protein interaction and literature mining to elucidate genetic networks regulating lipid related biological processes in lung. A Transcription factor (TF - target gene (TG similarity matrix was generated by integrating data from different analytic methods. A scoring function was built to rank the likely TF-TG pairs. Using this strategy, we identified and verified critical components of a transcriptional network directing lipogenesis, lipid trafficking and surfactant homeostasis in the mouse lung. Conclusions Within the transcriptional network, SREBP, CEBPA, FOXA2, ETSF, GATA6 and IRF1 were identified as regulatory hubs displaying high connectivity. SREBP, FOXA2 and CEBPA together form a common core regulatory module that controls surfactant lipid homeostasis. The core module cooperates with other factors to regulate lipid metabolism and transport, cell growth and development, cell death and cell mediated immune response. Coordinated interactions of the TFs influence surfactant homeostasis and regulate lung function at birth.

  20. Visual Sensing for Urban Flood Monitoring.

    Science.gov (United States)

    Lo, Shi-Wei; Wu, Jyh-Horng; Lin, Fang-Pang; Hsu, Ching-Han

    2015-08-14

    With the increasing climatic extremes, the frequency and severity of urban flood events have intensified worldwide. In this study, image-based automated monitoring of flood formation and analyses of water level fluctuation were proposed as value-added intelligent sensing applications to turn a passive monitoring camera into a visual sensor. Combined with the proposed visual sensing method, traditional hydrological monitoring cameras have the ability to sense and analyze the local situation of flood events. This can solve the current problem that image-based flood monitoring heavily relies on continuous manned monitoring. Conventional sensing networks can only offer one-dimensional physical parameters measured by gauge sensors, whereas visual sensors can acquire dynamic image information of monitored sites and provide disaster prevention agencies with actual field information for decision-making to relieve flood hazards. The visual sensing method established in this study provides spatiotemporal information that can be used for automated remote analysis for monitoring urban floods. This paper focuses on the determination of flood formation based on image-processing techniques. The experimental results suggest that the visual sensing approach may be a reliable way for determining the water fluctuation and measuring its elevation and flood intrusion with respect to real-world coordinates. The performance of the proposed method has been confirmed; it has the capability to monitor and analyze the flood status, and therefore, it can serve as an active flood warning system.

  1. Visual Sensing for Urban Flood Monitoring

    Directory of Open Access Journals (Sweden)

    Shi-Wei Lo

    2015-08-01

    Full Text Available With the increasing climatic extremes, the frequency and severity of urban flood events have intensified worldwide. In this study, image-based automated monitoring of flood formation and analyses of water level fluctuation were proposed as value-added intelligent sensing applications to turn a passive monitoring camera into a visual sensor. Combined with the proposed visual sensing method, traditional hydrological monitoring cameras have the ability to sense and analyze the local situation of flood events. This can solve the current problem that image-based flood monitoring heavily relies on continuous manned monitoring. Conventional sensing networks can only offer one-dimensional physical parameters measured by gauge sensors, whereas visual sensors can acquire dynamic image information of monitored sites and provide disaster prevention agencies with actual field information for decision-making to relieve flood hazards. The visual sensing method established in this study provides spatiotemporal information that can be used for automated remote analysis for monitoring urban floods. This paper focuses on the determination of flood formation based on image-processing techniques. The experimental results suggest that the visual sensing approach may be a reliable way for determining the water fluctuation and measuring its elevation and flood intrusion with respect to real-world coordinates. The performance of the proposed method has been confirmed; it has the capability to monitor and analyze the flood status, and therefore, it can serve as an active flood warning system.

  2. Jamming dynamics of stretch-induced surfactant release by alveolar type II cells.

    Science.gov (United States)

    Majumdar, Arnab; Arold, Stephen P; Bartolák-Suki, Erzsébet; Parameswaran, Harikrishnan; Suki, Béla

    2012-03-01

    Secretion of pulmonary surfactant by alveolar epithelial type II cells is vital for the reduction of interfacial surface tension, thus preventing lung collapse. To study secretion dynamics, rat alveolar epithelial type II cells were cultured on elastic membranes and cyclically stretched. The amounts of phosphatidylcholine, the primary lipid component of surfactant, inside and outside the cells, were measured using radiolabeled choline. During and immediately after stretch, cells secreted less surfactant than unstretched cells; however, stretched cells secreted significantly more surfactant than unstretched cells after an extended lag period. We developed a model based on the hypothesis that stretching leads to jamming of surfactant traffic escaping the cell, similar to vehicular traffic jams. In the model, stretch increases surfactant transport from the interior to the exterior of the cell. This transport is mediated by a surface layer with a finite capacity due to the limited number of fusion pores through which secretion occurs. When the amount of surfactant in the surface layer approaches this capacity, interference among lamellar bodies carrying surfactant reduces the rate of secretion, effectively creating a jam. When the stretch stops, the jam takes an extended time to clear, and subsequently the amount of secreted surfactant increases. We solved the model analytically and show that its dynamics are consistent with experimental observations, implying that surfactant secretion is a fundamentally nonlinear process with memory representing collective behavior at the level of single cells. Our results thus highlight the importance of a jamming dynamics in stretch-induced cellular secretory processes.

  3. Cyber Surveillance for Flood Disasters

    Directory of Open Access Journals (Sweden)

    Shi-Wei Lo

    2015-01-01

    Full Text Available Regional heavy rainfall is usually caused by the influence of extreme weather conditions. Instant heavy rainfall often results in the flooding of rivers and the neighboring low-lying areas, which is responsible for a large number of casualties and considerable property loss. The existing precipitation forecast systems mostly focus on the analysis and forecast of large-scale areas but do not provide precise instant automatic monitoring and alert feedback for individual river areas and sections. Therefore, in this paper, we propose an easy method to automatically monitor the flood object of a specific area, based on the currently widely used remote cyber surveillance systems and image processing methods, in order to obtain instant flooding and waterlogging event feedback. The intrusion detection mode of these surveillance systems is used in this study, wherein a flood is considered a possible invasion object. Through the detection and verification of flood objects, automatic flood risk-level monitoring of specific individual river segments, as well as the automatic urban inundation detection, has become possible. The proposed method can better meet the practical needs of disaster prevention than the method of large-area forecasting. It also has several other advantages, such as flexibility in location selection, no requirement of a standard water-level ruler, and a relatively large field of view, when compared with the traditional water-level measurements using video screens. The results can offer prompt reference for appropriate disaster warning actions in small areas, making them more accurate and effective.

  4. SYNTHESIS OF HYBRID MESOPOROUS POLYSTYRENE-SILICA MATERIALS WITH NON-SURFACTANT CITRIC ACID AS TEMPLATE VIA SOL-GEL PROCESS

    Institute of Scientific and Technical Information of China (English)

    Jie Bai; Jin-yu Zheng; Kun-yuan Qiu; Yen Wei

    2002-01-01

    Hybrid mesoporous polystyrene-silica materials were successfully prepared through HCl-catalyzed sol-gelreactions of tetraethyl orthosilicate (TEOS) and triethoxysilyl-functionalized polystyrene obtained via atom transfer radicalpolymerization (ATRP) of styrene, in the presence of citric acid (CA) as non-surfactant template or pore-forming agent andfollowed by ethanol extraction to remove template molecules. The materials were characterized by infrared spectroscopy(IR), N2 adsorption-desorption measurements, powder X-ray diffraction (XRD), thermogravimetric analysis (TGA) andtransmission electron microscopy (TEM). The results indicate that the materials prepared with 50 wt%-60 wt% templatecontents have average pore size s of 2-3 nm and large surface areas (ca. 886 m2/g) as well as high pore volumes (ca.0.53 cm3/g). The mesoporosity arises from interconnected channels and pores with disordered arrangements. The porediameters and pore volumes increase as the template content is increased. The pore diameters show a little change uponheating at 200℃ overnight. However, the materials do not have good hydrothermal stability.

  5. Flood Resilient Systems and their Application for Flood Resilient Planning

    Science.gov (United States)

    Manojlovic, N.; Gabalda, V.; Antanaskovic, D.; Gershovich, I.; Pasche, E.

    2012-04-01

    Following the paradigm shift in flood management from traditional to more integrated approaches, and considering the uncertainties of future development due to drivers such as climate change, one of the main emerging tasks of flood managers becomes the development of (flood) resilient cities. It can be achieved by application of non-structural - flood resilience measures, summarised in the 4As: assistance, alleviation, awareness and avoidance (FIAC, 2007). As a part of this strategy, the key aspect of development of resilient cities - resilient built environment can be reached by efficient application of Flood Resilience Technology (FReT) and its meaningful combination into flood resilient systems (FRS). FRS are given as [an interconnecting network of FReT which facilitates resilience (including both restorative and adaptive capacity) to flooding, addressing physical and social systems and considering different flood typologies] (SMARTeST, http://www.floodresilience.eu/). Applying the system approach (e.g. Zevenbergen, 2008), FRS can be developed at different scales from the building to the city level. Still, a matter of research is a method to define and systematise different FRS crossing those scales. Further, the decision on which resilient system is to be applied for the given conditions and given scale is a complex task, calling for utilisation of decision support tools. This process of decision-making should follow the steps of flood risk assessment (1) and development of a flood resilience plan (2) (Manojlovic et al, 2009). The key problem in (2) is how to match the input parameters that describe physical&social system and flood typology to the appropriate flood resilient system. Additionally, an open issue is how to integrate the advances in FReT and findings on its efficiency into decision support tools. This paper presents a way to define, systematise and make decisions on FRS at different scales of an urban system developed within the 7th FP Project

  6. Modelling Adsorption of Foam-Forming Surfactants Modélisation de l'adsorption des produits tensio-actifs moussants

    Directory of Open Access Journals (Sweden)

    Mannhardt K.

    2006-11-01

    Full Text Available There is considerable interest in the use of foam-forming surfactants for mobility control in gas flooding enhanced oil recovery processes. The success of any such process is strongly affected by the rate of propagation of the surfactant through the reservoir. A sound understanding of surfactant adsorption on rock surfaces at reservoir conditions is therefore essential. This paper describes a model for the evaluation of adsorption during flow of surfactant solutions through porous media. The adsorption term in the flow equation is expressed in terms of the surface excess which proves to be more generally applicable than, for example, the Langmuir adsorption isotherm. Adsorption isotherms of three types of commercially available foam-forming surfactants are determined from core flooding data at different temperatures and brine salinities. L'utilisation de produits tensio-actifs moussants pour le contrôle de mobilité dans les procédés de récupération assistée du pétrole par injection de gaz suscite actuellement un grand intérêt. Mais le succès d'un tel procédé dépend largement de la vitesse de propagation du tensioactif dans le réservoir. Il est donc indispensable d'avoir une bonne connaissance de l'adsorption du tensio-actif sur les surfaces de la roche, dans les conditions de réservoir. Cet article décrit un modèle qui permet d'évaluer l'adsorption pendant l'écoulement de solutions tensio-actives en milieu poreux. Le terme qui représente l'adsorption dans l'équation de l'écoulement est exprimé en fonction de l'excédent de surface, concept qui s'est révélé d'une application plus générale que, par exemple, l'isotherme d'adsorption de Langmuir. Les isothermes d'adsorption de trois types de tensio-actifs moussants disponibles sur le marché sont déterminées à partir de données obtenues lors d'essais de déplacement dans des carottes, à différentes températures et avec des saumures de différentes salinités.

  7. Coupling the Alkaline-Surfactant-Polymer Technology and The Gelation Technology to Maximize Oil Production

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson; David Stewart; Bill Jones

    2005-10-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or more efficient areal sweep efficiency for those with high permeability contrast ''thief zones''. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more oil than waterflooding from swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or those with thief zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. A prior fluid-fluid report discussed interaction of different gel chemical compositions and alkaline-surfactant-polymer solutions. Gel solutions under dynamic conditions of linear corefloods showed similar stability to alkaline-surfactant-polymer solutions as in the fluid-fluid analyses. Aluminum-polyacrylamide, flowing gels are not stable to alkaline-surfactant-polymer solutions of either pH 10.5 or 12.9. Chromium acetate-polyacrylamide flowing and rigid flowing gels are stable to subsequent alkaline-surfactant-polymer solution injection. Rigid flowing chromium acetate-polyacrylamide gels maintained permeability reduction better than flowing chromium acetate-polyacrylamide gels. Silicate-polyacrylamide gels are not stable with subsequent injection of either a pH 10.5 or a 12.9 alkaline-surfactant-polymer solution. Chromium acetate-xanthan gum rigid gels are not stable to subsequent alkaline-surfactant-polymer solution injection. Resorcinol-formaldehyde gels were stable to subsequent alkaline-surfactant-polymer solution injection. When evaluated in a dual core configuration, injected fluid flows into the core with the greatest effective permeability to the injected fluid. The same gel stability

  8. Innovation in surfactant therapy II: surfactant administration by aerosolization.

    Science.gov (United States)

    Pillow, J Jane; Minocchieri, S

    2012-01-01

    Instilled bolus surfactant is the only approved surfactant treatment for neonatal respiratory distress syndrome. However, recent trends towards increased utilization of noninvasive respiratory support for preterm infants with surfactant deficiency have created a demand for a similarly noninvasive means of administering exogenous surfactant. Past approaches to surfactant nebulization met with varying success due to inefficient aerosol devices resulting in low intrapulmonary delivery doses of surfactant with variable clinical effectiveness. The recent development of vibrating membrane nebulizers, coupled with appropriate positioning of the interface device, indicates that efficient delivery of aerosolized surfactant is now a realistic goal in infants. Evidence of clinical effect despite low total administered dose in pilot studies, together with suggestions of enhanced homogeneity of pulmonary distribution indicate that this therapy may be applied in a cost-effective manner, with minimal patient handling and disruption. These studies need to be subjected to appropriately designed randomized controlled trials. Further work is also required to determine the optimum delivery route (mask, intranasal prong, nasopharyngeal or laryngeal), dosing amount and redosing interval.

  9. Adsorption and intercalation of anionic surfactants onto layered double hydroxides—XRD study

    Indian Academy of Sciences (India)

    R Anbarasan; W D Lee; S S Im

    2005-04-01

    Layered double hydroxides (LDH) with brucite like structure was modified with various anionic surfactants containing sulfonate, carboxyl, phosphonate and sulfate end group through ion-exchange method. XRD reports indicated that the sulfonate group containing surfactants led to an adsorption process whereas the sulfate, carboxyl and phosphonate group containing surfactant led to an intercalation process. This can be evidenced from the change in basal spacing of LDH. The presence of anionic surfactants in the LDH was supported by FTIR spectroscopy. The FTIR spectrum indicated that complete removal of carbonate anion from the inter layer space of LDH is very difficult. The phosphonate intercalated HT showed less thermal stability than pristine LDH.

  10. POISON SPIDER FIELD CHEMICAL FLOOD PROJECT, WYOMING

    Energy Technology Data Exchange (ETDEWEB)

    Douglas Arnell; Malcolm Pitts; Jie Qi

    2004-11-01

    -rock compatibility, polymer injectivity, dynamic chemical retention by rock, and recommended injected polymer concentration. Average initial oil saturation was 0.796 Vp. Produced water injection recovered 53% OOIP leaving an average residual oil saturation of 0.375 Vp. Poison Spider rock was strongly water-wet with a mobility ratio for produced water displacing the 280 cp crude oil of 8.6. Core was not sensitive to either alkali or surfactant injection. Injectivity increased 60 to 80% with alkali plus surfactant injection. Low and medium molecular weight polyacrylamide polymers (Flopaam 3330S and Flopaam 3430S) dissolved in either an alkaline-surfactant solution or softened produced water injected and flowed through Poison Spider rock. Recommended injected polyacrylamide concentration is 2,100 mg/L for both polymers for a unit mobility ratio. Radial corefloods were performed to evaluate oil recovery efficiency of different chemical solutions. Waterflood oil recovery averaged 46.4 OOIP and alkaline-surfactant-polymer flood oil recovery averaged an additional 18.1% OIP for a total of 64.6% OOIP. Oil cut change due to injection of a 1.5 wt% Na{sub 2}CO{sub 3} plus 0.05 wt% Petrostep B-100 plus 0.05 wt% Stepantan AS1216 plus 2100 mg/L Flopaam 3430S was from 2% to a peak of 23.5%. Additional study might determine the impact on oil recovery of a lower polymer concentration. An alkaline-surfactant-polymer flood field implementation outline report was written.

  11. Interaction of nonionic surfactant AEO9 with ionic surfactants*

    OpenAIRE

    2005-01-01

    The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammonium bromide (CTAB) at molar fraction of AEO9, α AEO9=0.5. The surface properties of the surfactants, critical micelle concentration (CMC), effectiveness of surface tension reduction (γ CMC), maximum surface excess concentration (Γ max) and minimum area per...

  12. Coupling the Alkaline-Surfactant-Polymer Technology and The Gelation Technology to Maximize Oil Production

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson; Phil Dowling; David Stewart; Bill Jones

    2005-12-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or reservoirs with different sand lenses with high permeability contrast. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more crude oil than waterflooding from swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or reservoirs with high permeability contrast zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. Fluid-fluid interaction with different gel chemical compositions and alkaline-surfactant-polymer solution with pH values ranging from 9.2 to 12.9 have been tested. Aluminum-polyacrylamide gels are not stable to alkaline-surfactant-polymer solutions at any pH. Chromium-polyacrylamide gels with polymer to chromium ion ratios of 25 or greater were stable to alkaline-surfactant-polymer solutions if solution pH was 10.6 or less. When the polymer to chromium ion was 15 or less, chromium-polyacrylamide gels were stable to alkaline-surfactant-polymer solutions with pH values up to 12.9. Chromium-xanthan gum gels were stable to alkaline-surfactant-polymer solutions with pH values of 12.9 at the polymer to chromium ion ratios tested. Silicate-polyacrylamide, resorcinol-formaldehyde, and sulfomethylated resorcinol-formaldehyde gels were also stable to alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Iron-polyacrylamide gels were immediately destroyed when contacted with any of the alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Gel solutions under dynamic conditions of linear corefloods showed similar stability to alkaline-surfactant-polymer solutions as in

  13. Use of highly saline ethoxylated surfactant system for oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Reisberg, J.

    1970-03-17

    An aqueous solution of a sulfated polyoxylated primary alcohol and a soluble inorganic electrolyte was used for enhanced oil recovery. The electrolyte should be present in a concentration exceeding the critical concentration for forming a two-phase coacervate system, by an amount sufficient to convert the two-phase system to a turbid dispersion. The dispersion permits an interfacial tension with petroleum of 10/sup -4/ dynes/cm. A berea core (400 md) was flooded to residual oil saturation before flooding with a 4 M sodium chloride brine which contained Tergitol 15-S4 (4 ethylene oxide units, sodium salt). A 1 PV slug of the surfactant solution left only about 7 percent PV of oil.

  14. 凌汛期槽蓄水增量过程模拟%Simulation of channel-storage increment process in ice flood period

    Institute of Scientific and Technical Information of China (English)

    张防修; 席广永; 张晓丽; 王国庆; 黄瑞

    2015-01-01

    The channel⁃storage increment was normally divided into three parts including backwater increment, ice increment in the channel and on the beach, detention water by ice cover and ice jam based on observations. In order to investigate the major sources of channel⁃storage increment during ice flood season, a river ice dynamics model was established to simulate channel⁃storage increment process ( e�g. growth and decay processes of river ice) . The model was then applied to the river channel from the Sanhuhekou station to the Toudaoguai station located in the Inner Mon⁃golia. Results show that flood detention under beach ice cover is the principle source of channel storage increment, ac⁃counting for about 63�44% of the maximum channel storage increment. The channel stem storage increment and river ice share the rest increment, accounting for approximately 26�56%, 10% of total increment.%为研究凌汛期槽蓄水增量来源,在分析实测冰情资料基础上,把槽蓄水增量分为水位壅高主河道蓄水量增大、主河道内河水转化为固体冰盖和上滩水形成冰盖及在冰下聚集等3部分,建立河冰动力学模型,模拟河冰生消及槽蓄水增量过程,利用2008/2009年度三湖河口—头道拐河段实测冰情资料对模型进行了验证,表明滩地冰盖及冰盖下滞洪是内蒙古河段槽蓄水增量的主要来源,占最大槽蓄水增量的63�44%,主河道水位壅高引起的槽蓄水增量占26�56%,主槽冰盖蓄水占10�0%。

  15. Solubilization isotherms of aromatic solutes in surfactant aggregates

    Energy Technology Data Exchange (ETDEWEB)

    Gadelle, F.; Koros, W.J.; Schechter, R.S. (Univ. of Texas, Austin, TX (United States). Dept. of Chemical Engineering)

    1995-03-01

    Several factors affecting solubilization of aromatic solutes in surfactant micelles have been investigated. Solubilization isotherms of benzene, toluene, and chlorobenzene in various aqueous micellar solutions were determined using head space gas chromatography. Cationic surfactants such as cetylpyridinium chloride or cetyltrimethylammonium bromide present high solubilization capacities. Comparable anionic surfactants exhibit lower solubilization and a greater tendency to precipitate. It was observed that nonionic surfactants show high solubilization on a molar basis. Solubilization in mixed cationic-anionic micelles was also investigated. It also appears that the molecular size of the solute determines the extent of the solubilization. Finally, the shape of the different isotherms indicates that knowing the amount solubilized at saturation of the micellar solution is not sufficient to estimate solubilization at solute concentrations lower than the solute aqueous solubility. Solubilization of organics in surfactant micelles is of major importance in many applications. One new application is micellar-enhanced ultrafiltration. Another application of interest is the surfactant-enhanced aquifer remediation, a process in which a micellar aqueous solution is flushed into contaminated groundwaters to enhance recovery of pollutants by micellar solubilization.

  16. Flood risk control of dams and dykes in middle reach of Huaihe River

    Directory of Open Access Journals (Sweden)

    Zhen-kun MA

    2014-01-01

    Full Text Available Three stochastic mathematical models for calculation of the reservoir flood regulation process, river course flood release, and flood risk rate under flood control were established based on the theory of stochastic differential equations and features of flood control systems in the middle reach of the Huaihe River from Xixian to the Bengbu floodgate, comprehensively considering uncertain factors of hydrology, hydraulics, and engineering control. They were used to calculate the flood risk rate with flood regulation of five key reservoirs, including the Meishan, Xianghongdian, Nianyushan, Mozitan, and Foziling reservoirs in the middle reach of the Huaihe River under different flood frequencies, the flood risk rate with river course flood release under design and check floods for the trunk of the Huaihe River in conjunction with relevant flood storage areas, and the flood risk rate with operation of the Linhuaigang Project under design and check floods. The calculated results show that (1 the five reservoirs can withstand design floods, but the Xianghongdian and Foziling reservoirs will suffer overtopping accidents under check floods; (2 considering the service of flood storage areas under the design flood conditions of the Huaihe River, the mean flood risk rate with flood regulation of dykes and dams from Xixian to the Bengbu floodgate is about 0.2, and the trunk of the Huaihe River can generally withstand design floods; and (3 under a check flood with the flood return period of 1 000 years, the risk rate of overtopping accidents of the Linhuaigang Project is not larger than 0.15, indicating that it has a high flood regulation capacity. Through regulation and application of the flood control system of the Linhuigang Project, the Huaihe River Basin can withstand large floods, and the safety of the protected area can be ensured.

  17. Study on Treatment of Surfactant Wastewater by Coagulation and Membrane Separation Integrated Process%混凝-膜分离集成工艺处理表面活性剂废水的研究

    Institute of Scientific and Technical Information of China (English)

    王建明; 王汉斌; 仲晓晴; 宋宏臣

    2016-01-01

    Surfactants have complex compositions and low molecular weights, which usually leads to the eutrophication of waterbodies. For the treatment of wastewater that contains surfactants, the membrane separation technology is usually adopted. However, the membrane is easily polluted and the cleaning process is usually laborious. In this work, a new surfactants wastewater processing technology was investigated by combining the coagulation and membrane separation techniques. Firstly, the phase inversion technique was used for the preparation of titanium dioxide modiifed polyvinylidene lfuoride ultraifltration membrane. Structure and properties of the membrane are tested by several instrumentations, like the scanning electron microscopy, fourier transform infrared spectroscopy, and contact angle instrument. Secondly, using sodium dodecyl benzene sulfonate solution and polymerization aluminum chloride as surfactant wastewater and coagulant respectively, the treatment effect is evaluated with respect to ultraviolet light intensity, water lfow rate and pH values. By observation, the modified membrane has dense-selective layer on the surface, and its cross-section is composed with finger holes and spongy structures. By the analysis of fourier transform infrared spectroscopy, polyethylene glycol and titanium dioxide in the modiifed membrane can cover apart of infrared absorption of polyvinylidene lfuoride. The modiifed membrane has relative small contact angle and its performance is also insensitive to the change of ultraviolet light intensity and water lfow rate. Moreover, the process can reach best performance while the wastewater with pH value of 4.5. The proposed surfactants wastewater process technique has distinct advantages of high efifciency and low-cost, which makes it with great potentials in the application of large scale industrial and domestic wastewater processing.%废水中的表面活性剂成分复杂、分子量小,若不经处理直接排入水体,将造

  18. Extreme flood events in the Bolivian Amazon wetlands

    Directory of Open Access Journals (Sweden)

    A. Ovando

    2016-03-01

    New hydrological insights for the region: The results showed that large floods are the result of the superimposition of flood waves from major sub-basins of the region. As a previous study suggested, the dynamics of the floods are controlled by an exogenous process, created by the flood wave originating in the Andes piedmont that travels through the Mamoré River; and by an endogenous process, which is the runoff originating in the Llanos. Our study showed that the first process is evident only at the initial phase of the floods, and although important for attenuating the rising flood wave, it is of lesser importance compared to the endogenous process. We conclude that the endogenous process controls the magnitude and duration of major floods.

  19. Review of the flood risk management system in Germany after the major flood in 2013

    Directory of Open Access Journals (Sweden)

    Annegret H. Thieken

    2016-06-01

    Full Text Available Widespread flooding in June 2013 caused damage costs of €6 to 8 billion in Germany, and awoke many memories of the floods in August 2002, which resulted in total damage of €11.6 billion and hence was the most expensive natural hazard event in Germany up to now. The event of 2002 does, however, also mark a reorientation toward an integrated flood risk management system in Germany. Therefore, the flood of 2013 offered the opportunity to review how the measures that politics, administration, and civil society have implemented since 2002 helped to cope with the flood and what still needs to be done to achieve effective and more integrated flood risk management. The review highlights considerable improvements on many levels, in particular (1 an increased consideration of flood hazards in spatial planning and urban development, (2 comprehensive property-level mitigation and preparedness measures, (3 more effective flood warnings and improved coordination of disaster response, and (4 a more targeted maintenance of flood defense systems. In 2013, this led to more effective flood management and to a reduction of damage. Nevertheless, important aspects remain unclear and need to be clarified. This particularly holds for balanced and coordinated strategies for reducing and overcoming the impacts of flooding in large catchments, cross-border and interdisciplinary cooperation, the role of the general public in the different phases of flood risk management, as well as a transparent risk transfer system. Recurring flood events reveal that flood risk management is a continuous task. Hence, risk drivers, such as climate change, land-use changes, economic developments, or demographic change and the resultant risks must be investigated at regular intervals, and risk reduction strategies and processes must be reassessed as well as adapted and implemented in a dialogue with all stakeholders.

  20. Reconstruction of the 1945 Wieringermeer Flood

    Science.gov (United States)

    Hoes, O. A. C.; Hut, R. W.; van de Giesen, N. C.; Boomgaard, M.

    2013-03-01

    The present state-of-the-art in flood risk assessment focuses on breach models, flood propagation models, and economic modelling of flood damage. However, models need to be validated with real data to avoid erroneous conclusions. Such reference data can either be historic data, or can be obtained from controlled experiments. The inundation of the Wieringermeer polder in the Netherlands in April 1945 is one of the few examples for which sufficient historical information is available. The objective of this article is to compare the flood simulation with flood data from 1945. The context, the breach growth process and the flood propagation are explained. Key findings for current flood risk management addresses the importance of the drainage canal network during the inundation of a polder, and the uncertainty that follows from not knowing the breach growth parameters. This case study shows that historical floods provide valuable data for the validation of models and reveal lessons that are applicable in current day flood risk management.

  1. Effect of curcumin on the binding of cationic, anionic and nonionic surfactants with myoglobin

    Science.gov (United States)

    Mondal, Satyajit; Ghosh, Soumen

    2017-04-01

    Interaction of a globular protein, myoglobin and different surfactants has been studied in the absence and presence of curcumin in phosphate buffer at pH = 7.4 by UV-VIS spectrophotometry, fluorimetry and fluorescence polarization anisotropy methods. Results show that heme environment of myoglobin is changed by cationic cetyltrimethylammonium bromide (CTAB) and sodium N-dodecanoyl sarcosinate (SDDS). In the presence of curcumin, CTAB cannot change the heme; but SDDS can make change. Nonionic surfactant N-decanoyl-N-methylglucamine (Mega 10) cannot change the heme environment. Protein is unfolded by the surfactant. Curcumin can prevent the unfolding of protein in the low concentration region of ionic surfactants such as CTAB and SDDS. In nonionic surfactant media, curcumin accelerates the denaturation process. Due to myoglobin-curcumin complex formation, rotational motion of curcumin decreases in surfactant media and so anisotropy increases.

  2. Treatment with exogenous surfactant stimulates endogenous surfactant synthesis in premature infants with respiratory distress syndrome

    NARCIS (Netherlands)

    Bunt, JEH; Carnielli, VP; Janssen, DJ; Wattimena, JLD; Hop, WC; Sauer, PJ; Zimmermann, LJI

    2000-01-01

    Objective: Treatment of preterm infants with respiratory distress syndrome (RDS) with exogenous surfactant has greatly improved clinical outcome. Some infants require multiple doses, and it has not been studied whether these large amounts of exogenous surfactant disturb endogenous surfactant metabol

  3. Flood Risk Management In Europe: an exploration of governance challenges

    NARCIS (Netherlands)

    Hegger, D.; Dieperink, C.; Green, C.; Driessen, Peter; Bakker, M.H.; Rijswick, H.F.M.W. van; Crabbé, A.; Ek, K.

    2013-01-01

    In order to make European regions more resilient to flood risks a broadening of Flood Risk Management strategies (FRMSs) might be necessary. The development and implementation of FRMSs like risk prevention, flood defence, mitigation, preparation and recovery is a matter of governance, a process of

  4. Electrochemical Oscillations Induced by Surfactants

    Institute of Scientific and Technical Information of China (English)

    翟俊红; 贺占博

    2003-01-01

    A new type of electrochemical oscillation induced by surfactant was observed in experiments. The electrochemical system is a Daniell cell with a copper rod in CuSO4 aqueous and an aluminum rod in Al(NO3)3 aqueous as electrodes. The surfactants are CTAB, TX-100, SLS. The addition of trace surfactant solution by a micro-syringe made the original monotonously changing electrochemical system produce obvious periodic phenomena. At the mean time, the copper ion selective electrode and Hg2SO4 reference electrode were used to monitor the copper electrode reaction and determine its rate constant k of first order reaction. According to the experimental results of electrode reaction kinetics, the possible mechanism was found to be the polarization induced from the directional adsorption of trace surfactant on the electrode surface. That is the electrochemical oscillations.

  5. Visualization of TCE recovery mechanisms using surfactant-polymer solutions in a two-dimensional heterogeneous sand model.

    Science.gov (United States)

    Robert, Thomas; Martel, Richard; Conrad, Stephen H; Lefebvre, René; Gabriel, Uta

    2006-06-30

    This research focused on the optimization of TCE dissolution in a physical two-dimensional model providing a realistic representation of a heterogeneous granular aquifer. TCE was infiltrated in the sand pack where it resided both in pools and in zones of residual saturation. Surfactant was initially injected at low concentration to minimize TCE remobilization at first contact but was incrementally increased later during the experiment. Xanthan gum was added to the injected surfactant solution to optimize the sweep efficiency through the heterogeneous medium. Photographs and digital image analysis illustrated the interactions between TCE and the injected fluids. During the polymer flood, the effects of heterogeneities inside the sand pack were greatly reduced by the increased fluid viscosity and the shear-thinning effects of the polymer. The polymer also improved the contact between the TCE ganglia and the surfactant-polymer solution, thereby promoting dissolution. Surfactants interacted with the polymer reducing the overall viscosity of the solution. At first contact with a 0.5%(mass) surfactant solution, the TCE pools drained and some remobilization occurred. However, no TCE bank was formed and TCE did not penetrate into any previously uncontaminated areas. As a result, TCE surface area was increased. Subsequent surfactant floods at higher surfactant concentrations did not trigger more remobilization. TCE was mainly dissolved by the solution with the highest surfactant concentration. Plugging from bacterial growth or microgel formation associated to the polymer at the inflow screen prevented the full completion of the experiment. However, more than 90% of TCE was recovered with the circulation of less than 6 pore volumes of surfactant-polymer solution.

  6. Surfactant-laden drop jellyfish-breakup mode induced by the Marangoni effect

    Science.gov (United States)

    Zhao, Hui; Zhang, Wen-Bin; Xu, Jian-Liang; Li, Wei-Feng; Liu, Hai-Feng

    2017-03-01

    Drop breakup is a familiar event in both nature and technology. In this study, we find that the bag breakup mode can be replaced by a new breakup mode: jellyfish breakup, when the surfactant concentration of a surfactant-laden drop is high. This new breakup mode has a morphology resembling a jellyfish with many long tentacles. This is due to the inhomogeneous distribution of surfactant in the process of drop deformation and breakup. The thin film of liquid can remain stable as a result of the Marangoni effect. Finally, we propose that the dimensionless surfactant concentration can serve as a criterion for breakup mechanisms.

  7. Jet A fuel recovery using micellar flooding: Design and implementation.

    Science.gov (United States)

    Kostarelos, Konstantinos; Lenschow, Søren R; Stylianou, Marinos A; de Blanc, Phillip C; Mygind, Mette Marie; Christensen, Anders G

    2016-09-01

    Surfactants offer two mechanisms for recovering NAPLs: 1) to mobilize NAPL by reducing NAPL/water interfacial tension, and; 2) to increase the NAPL's aqueous solubility-called solubilization-as an enhancement to pump & treat. The second approach has been well-studied and applied successfully in several pilot-scale and a few full-scale tests within the last 15years, known as Surfactant Enhanced Aquifer Remediation (SEAR). A useful source of information for this second approach is the "Surfactant-enhanced aquifer remediation (SEAR) design manual" from the U.S. Navy Facilities Engineering Command. Few attempts, however, have been made at recovering NAPLs using the mobilization approach presented in this paper. Now, a full-scale field implementation of the mobilization approach is planned to recover an LNAPL (Jet A fuel) from a surficial sand aquifer located in Denmark using a smaller amount of surfactant solution and fewer PVs of throughput compared with the SEAR approach. The approach will rely on mobilizing the LNAPL so that it is recovered ahead of the surfactant microemulsion, also known as a micellar flood. This paper will review the laboratory work performed as part of the design for a full-scale implementation of a micellar flood. Completed lab work includes screening of surfactants, phase behavior and detailed salinity scans of the most promising formulations, and generating a ternary diagram to be used for the numerical simulations of the field application. The site owners and regulators were able to make crucial decisions such as the anticipated field results based on this work.

  8. Therapeutic surfactant-stripped frozen micelles

    Science.gov (United States)

    Zhang, Yumiao; Song, Wentao; Geng, Jumin; Chitgupi, Upendra; Unsal, Hande; Federizon, Jasmin; Rzayev, Javid; Sukumaran, Dinesh K.; Alexandridis, Paschalis; Lovell, Jonathan F.

    2016-05-01

    Injectable hydrophobic drugs are typically dissolved in surfactants and non-aqueous solvents which can induce negative side-effects. Alternatives like `top-down' fine milling of excipient-free injectable drug suspensions are not yet clinically viable and `bottom-up' self-assembled delivery systems usually substitute one solubilizing excipient for another, bringing new issues to consider. Here, we show that Pluronic (Poloxamer) block copolymers are amenable to low-temperature processing to strip away all free and loosely bound surfactant, leaving behind concentrated, kinetically frozen drug micelles containing minimal solubilizing excipient. This approach was validated for phylloquinone, cyclosporine, testosterone undecanoate, cabazitaxel and seven other bioactive molecules, achieving sizes between 45 and 160 nm and drug to solubilizer molar ratios 2-3 orders of magnitude higher than current formulations. Hypertonic saline or co-loaded cargo was found to prevent aggregation in some cases. Use of surfactant-stripped micelles avoided potential risks associated with other injectable formulations. Mechanistic insights are elucidated and therapeutic dose responses are demonstrated.

  9. Systematic Phase Behaviour Study and Foam Stability Analysis for Optimal Alkaline/Surfactant/Foam Enhanced Oil Recovery

    NARCIS (Netherlands)

    Hosseini Nasab, S.M.; Zitha, P.L.J.

    2015-01-01

    Alkaline-Surfactant-Foam (ASF) flooding is a recently introduced enhanced oil recovery (EOR) method. This paper presents laboratory study of this ASF to better understand its mechanisms. The focus is on the interaction of ASF chemical agents with oil and in the presence and absence of naphthenic com

  10. Systematic Phase Behaviour Study and Foam Stability Analysis for Optimal Alkaline/Surfactant/Foam Enhanced Oil Recovery

    NARCIS (Netherlands)

    Hosseini Nasab, S.M.; Zitha, P.L.J.

    2015-01-01

    Alkaline-Surfactant-Foam (ASF) flooding is a recently introduced enhanced oil recovery (EOR) method. This paper presents laboratory study of this ASF to better understand its mechanisms. The focus is on the interaction of ASF chemical agents with oil and in the presence and absence of naphthenic com

  11. Persurf, a New Method to Improve Surfactant Delivery: A Study in Surfactant Depleted Rats

    OpenAIRE

    2012-01-01

    PURPOSE: Exogenous surfactant is not very effective in adults with ARDS, since surfactant does not reach atelectatic alveoli. Perfluorocarbons (PFC) can recruit atelectatic areas but do not replace impaired endogenous surfactant. A surfactant-PFC-mixture could combine benefits of both therapies. The aim of the proof-of-principal-study was to produce a PFC-in-surfactant emulsion (Persurf) and to test in surfactant depleted Wistar rats whether Persurf achieves I.) a more homogenous pulmonary di...

  12. Deriving global flood hazard maps of fluvial floods through a physical model cascade

    OpenAIRE

    Pappenberger, F.; E. Dutra; Wetterhall, F.; Cloke, H

    2012-01-01

    Global flood hazard maps can be used in the assessment of flood risk in a number of different applications, including (re)insurance and large scale flood preparedness. Such global hazard maps can be generated using large scale physically based models of rainfall-runoff and river routing, when used in conjunction with a number of post-processing methods. In this study, the European Centre for Medium Range Weather Forecasts (ECMWF) land surface model is coupled to ERA-Interim reanalysis meteoro...

  13. South China Flooded

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Vehicles traverse a flooded street in Liuzhou, guangxi zhuang Autonomous Region, on May 19.heavy rainstorms repeatedly struck China this month, triggering floods, mudflows and landslides. hunan, guangdong and Jiangxi provinces and Chongqing Municipality were the worst hit.

  14. Base Flood Elevation

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  15. Flood Control Structures

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  16. Flooding: Prioritizing protection?

    Science.gov (United States)

    Peduzzi, Pascal

    2017-09-01

    With climate change, urban development and economic growth, more assets and infrastructures will be exposed to flooding. Now research shows that investments in flood protection are globally beneficial, but have varied levels of benefit locally.

  17. Flood Hazard Area

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  18. Flood Hazard Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The National Flood Hazard Layer (NFHL) data incorporates all Digital Flood Insurance Rate Map(DFIRM) databases published by FEMA, and any Letters Of Map Revision...

  19. Flood Risk Regional Flood Defences: Technical report

    NARCIS (Netherlands)

    Lendering, K.T.

    2015-01-01

    Historically the Netherlands have always had to deal with the threat of flooding, both from the rivers and the sea as well as from heavy rainfall. The country consists of a large amount of polders, which are low lying areas of land protected from flooding by embankments. These polders require an

  20. Flood Risk Regional Flood Defences: Technical report

    NARCIS (Netherlands)

    Lendering, K.T.

    2015-01-01

    Historically the Netherlands have always had to deal with the threat of flooding, both from the rivers and the sea as well as from heavy rainfall. The country consists of a large amount of polders, which are low lying areas of land protected from flooding by embankments. These polders require an ext

  1. Synthesis and properties evaluation of nonionic-anionic surfactants suitable for enhanced oil recovery using sea water

    Energy Technology Data Exchange (ETDEWEB)

    Sha Ou [Lanzhou Inst. of Chemical Physics, Chinese Academy of Sciences (China); Shanghai Petrochemical Research Inst., SINOPEC (China); Zhang Weidong [Shanghai Petrochemical Research Inst., SINOPEC (China); Lu Runhua [Chengdu Inst. of Biology, Chinese Academy of Sciences (China)

    2008-03-15

    In view of imperfections of conventional anionic and nonionic surfactants used for enhanced oil recovery, especially the characteristics of high salinity and high Calcium/Magnesium for sea water flooding, a new novel displacement agent suitable for sea water flooding was synthesized through alkoxylation, epoxidation, sulfonation reaction with fatty alcohol as core. The structure of the product was characterized by IR. The properties of the product, including salt tolerance, temperature resistance etc. were evaluated. At 70 C, when the concentration of this surfactant is 0.3%, the interfacial tension between simulated water solution and Bohai1A-4 well crude reaches 10{sup -3} mN/m order, the salt tolerance reaches 50 000 mg/L, the resistance to calcium and magnesium reaches 2000 mg/L. The laboratory physical simulation test shows that the binary complex system (polymer + surfactant) can enhance the recovery ratio by 17.9%, while better synergistic effect of the system is obtained. (orig.)

  2. Uncertainty in flood risk mapping

    Science.gov (United States)

    Gonçalves, Luisa M. S.; Fonte, Cidália C.; Gomes, Ricardo

    2014-05-01

    A flood refers to a sharp increase of water level or volume in rivers and seas caused by sudden rainstorms or melting ice due to natural factors. In this paper, the flooding of riverside urban areas caused by sudden rainstorms will be studied. In this context, flooding occurs when the water runs above the level of the minor river bed and enters the major river bed. The level of the major bed determines the magnitude and risk of the flooding. The prediction of the flooding extent is usually deterministic, and corresponds to the expected limit of the flooded area. However, there are many sources of uncertainty in the process of obtaining these limits, which influence the obtained flood maps used for watershed management or as instruments for territorial and emergency planning. In addition, small variations in the delineation of the flooded area can be translated into erroneous risk prediction. Therefore, maps that reflect the uncertainty associated with the flood modeling process have started to be developed, associating a degree of likelihood with the boundaries of the flooded areas. In this paper an approach is presented that enables the influence of the parameters uncertainty to be evaluated, dependent on the type of Land Cover Map (LCM) and Digital Elevation Model (DEM), on the estimated values of the peak flow and the delineation of flooded areas (different peak flows correspond to different flood areas). The approach requires modeling the DEM uncertainty and its propagation to the catchment delineation. The results obtained in this step enable a catchment with fuzzy geographical extent to be generated, where a degree of possibility of belonging to the basin is assigned to each elementary spatial unit. Since the fuzzy basin may be considered as a fuzzy set, the fuzzy area of the basin may be computed, generating a fuzzy number. The catchment peak flow is then evaluated using fuzzy arithmetic. With this methodology a fuzzy number is obtained for the peak flow

  3. Simulating floods : On the application of a 2D-hydraulic model for flood hazard and risk assessment

    OpenAIRE

    Alkema, D.

    2007-01-01

    Over the last decades, river floods in Europe seem to occur more frequently and are causing more and more economic and emotional damage. Understanding the processes causing flooding and the development of simulation models to evaluate countermeasures to control that damage are important issues. This study deals with the application of a 2D hydraulic flood propagation model for flood hazard and risk assessment. It focuses on two components: 1) how well does it predict the spatial-dynamic chara...

  4. Characterization of remarkable floods in France, a transdisciplinary approach applied on generalized floods of January 1910

    Science.gov (United States)

    Boudou, Martin; Lang, Michel; Vinet, Freddy; Coeur, Denis

    2014-05-01

    The 2007 Flood Directive promotes the integration and valorization of historical and significant floods in flood risk management (Flood Directive Text, chapter II, and article 4). Taking into account extreme past floods analysis seems necessary in the mitigation process of vulnerability face to flooding risk. In France, this aspect of the Directive was carried out through the elaboration of Preliminary Flood Risk Assessment (PFRA) and the establishment of a 2000 floods list. From this first list, a sample of 176 floods, considered as remarkable has been selected. These floods were compiled in discussion with local authorities in charge of flood management (Lang et al., 2012) and have to be integrated in priority in local risk management policies. However, a consideration emerges about this classification: how a remarkable flood can be defined? According which criteria can it be considered as remarkable? To answer these questions, a methodology has been established by building an evaluation grid of remarkable floods in France. The primary objective of this grid is to analyze the remarkable flood's characteristics (hydrological and meteorological characteristics, sociological- political and economic impacts), and secondly to propose a classification of significant floods selected in the 2011 PFRA. To elaborate this evaluation grid, several issues had to be taken into account. First, the objective is to allow the comparison of events from various periods. These temporal disparities include the integration of various kinds of data and point out the importance of historical hydrology. It is possible to evaluate accurately the characteristics of recent floods by interpreting quantitative data (for example hydrological records. However, for floods that occurred before the 1960's it is necessary resorting to qualitative information such as written sources is necessary (Coeur, Lang, 2008). In a second part the evaluation grid requires equitable criteria in order not to

  5. National flood modelling for insurance purposes: using IFSAR for flood risk estimation in Europe

    Directory of Open Access Journals (Sweden)

    R. Sanders

    2005-01-01

    Full Text Available Flood risk poses a major problem for insurers and governments who ultimately pay the financial costs of losses resulting from flood events. Insurers therefore face the problem of how to assess their exposure to floods and how best to price the flood element of their insurance products. This paper looks at the insurance implications of recent flood events in Europe and the issues surrounding insurance of potential future events. In particular, the paper will focus on the flood risk information needs of insurers and how these can be met. The data requirements of national and regional flood models are addressed in the context of the accuracy of available data on property location. Terrain information is generally the weakest component of sophisticated flood models. Therefore, various sources of digital terrain models (DTM are examined and discussed with consideration of the vertical and horizontal accuracy, the speed of acquisition, the costs and the comprehensiveness of the data. The NEXTMap DTM series from Intermap Technologies Inc. is proposed as a suitable DTM for flood risk identification and mapping, following its use in the UK. Its acquisition, processing and application is described and future plans discussed. Examples are included of the application of flood information to insurance property information and the potential benefits and advantages of using suitable hazard modelling data sources are detailed.

  6. Biomimicry of surfactant protein C.

    Science.gov (United States)

    Brown, Nathan J; Johansson, Jan; Barron, Annelise E

    2008-10-01

    Since the widespread use of exogenous lung surfactant to treat neonatal respiratory distress syndrome, premature infant survival and respiratory morbidity have dramatically improved. Despite the effectiveness of the animal-derived surfactant preparations, there still remain some concerns and difficulties associated with their use. This has prompted investigation into the creation of synthetic surfactant preparations. However, to date, no clinically used synthetic formulation is as effective as the natural material. This is largely because the previous synthetic formulations lacked analogues of the hydrophobic proteins of the lung surfactant system, SP-B and SP-C, which are critical functional constituents. As a result, recent investigation has turned toward the development of a new generation of synthetic, biomimetic surfactants that contain synthetic phospholipids along with a mimic of the hydrophobic protein portion of lung surfactant. In this Account, we detail our efforts in creating accurate mimics of SP-C for use in a synthetic surfactant replacement therapy. Despite SP-C's seemingly simple structure, the predominantly helical protein is extraordinarily challenging to work with given its extreme hydrophobicity and structural instability, which greatly complicates the creation of an effective SP-C analogue. Drawing inspiration from Nature, two promising biomimetic approaches have led to the creation of rationally designed biopolymers that recapitulate many of SP-C's molecular features. The first approach utilizes detailed SP-C structure-activity relationships and amino acid folding propensities to create a peptide-based analogue, SP-C33. In SP-C33, the problematic and metastable polyvaline helix is replaced with a structurally stable polyleucine helix and includes a well-placed positive charge to prevent aggregation. SP-C33 is structurally stable and eliminates the association propensity of the native protein. The second approach follows the same design

  7. Flood Mitigation of Nyando River Using Duflow Modelling

    Directory of Open Access Journals (Sweden)

    J. Joleha

    2009-01-01

    Full Text Available Duflow surface water hydrodynamic model has been applied using a case study from Nyando catchment in the western part of Kenya in Africa to simulate various extreme flood behaviours and their retardation levels by using selected structural measures as flood mitigation techniques. The objective of this case study was to establish a design flood recommendable for mitigation, and to identify the most cost effective flood mitigation structure. Various design flows are simulated against the different proposed structures hence, the optimal structure can be recommended when economical, social and environmental constraints are considered in the decision making process. The proposed four flood mitigation structures flood plain extension, embankment (dykes, channel by-pass, and green-storage were simulated for 20-year recurrence interval flood to determine their individual responses in storing excess water. The result shows that building a green-storage is the best and optimal structure for flood mitigation.

  8. Effect of Textured Surfactant Brushes on Polymer-Layered Silicate Nanocomposite Morphology

    Science.gov (United States)

    2004-02-01

    melt processing a mixture of stearylammonium-exchanged montmorillonite, maleic anhydride -modified polypropylene oligomer, and homopolypropylene (29–31...molecular weights was performed using both the XMASS (Bruker) and Polymerix (Sierra Analytics) software packages. Surfactant nomenclature and...properties are recorded in table 1. The nomenclature used is such that for any surfactant it provides information about its approximate molecular weight

  9. Floods in mountain environments: A synthesis

    Science.gov (United States)

    Stoffel, Markus; Wyżga, Bartłomiej; Marston, Richard A.

    2016-11-01

    Floods are a crucial agent of geomorphic change in the channels and valley floors of mountains watercourses. At the same time, they can be highly damaging to property, infrastructure, and life. Because of their high energy, mountain watercourses are highly vulnerable to environmental changes affecting their catchments and channels. Many factors have modified and frequently still tend to modify the environmental conditions in mountain areas, with impacts on geomorphic processes and the frequency, magnitude, and timing of floods in mountain watercourses. The ongoing climate changes vary between regions but may affect floods in mountain areas in many ways. In many mountain regions of Europe, widespread afforestation took place over the twentieth century, considerably increasing the amounts of large wood delivered to the channels and the likelihood of jamming bridges. At the same time, deforestation continues in other mountain areas, accelerating runoff and amplifying the magnitude and frequency of floods in foreland areas. In many countries, in-channel gravel mining has been a common practice during recent decades; the resultant deficit of bed material in the affected channels may suddenly manifest during flood events, resulting in the failure of scoured bridges or catastrophic channel widening. During the past century many rivers in mountain and foreland areas incised deeply; the resultant loss of floodplain water storage has decreased attenuation of flood waves, hence increasing flood hazard to downstream river reaches. On the other hand, a large amount of recent river restoration activities worldwide may provide examples of beneficial changes to flood risk, attained as a result of increased channel storage or reestablished floodplain water storage. Relations between geomorphic processes and floods operate in both directions, which means that changes in flood probability or the character of floods (e.g., increased wood load) may significantly modify the morphology

  10. Surfactant for pediatric acute lung injury.

    Science.gov (United States)

    Willson, Douglas F; Chess, Patricia R; Notter, Robert H

    2008-06-01

    This article reviews exogenous surfactant therapy and its use in mitigating acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS) in infants, children, and adults. Biophysical and animal research documenting surfactant dysfunction in ALI/ARDS is described, and the scientific rationale for treatment with exogenous surfactant is discussed. Major emphasis is placed on reviewing clinical studies of surfactant therapy in pediatric and adult patients who have ALI/ARDS. Particular advantages from surfactant therapy in direct pulmonary forms of these syndromes are described. Also discussed are additional factors affecting the efficacy of exogenous surfactants in ALI/ARDS.

  11. Flood loss assessment in Can Tho City, Vietnam

    Science.gov (United States)

    Do, T. C.; Kreibich, H.

    2012-04-01

    Floods are recurring events in the Lower Mekong Basin resulting in loss of life and property, causing damage to agriculture and rural infrastructure, and disrupting social and economic activities. Flood management and mitigation has become a priority issue at the national and regional levels. Besides, it is expected that large areas of the Mekong delta, the Red River delta and the central coast will be flooded by sea-level rise due to climate change. Can Tho City is ranked under the five most flood-tide-influenced cities of Vietnam. It is the biggest city in the Mekong delta and it is located near the Hau river. Like other region of the Mekong delta, Can Tho suffers due to floods from upstream and flood tides from the sea. In the flood season large rural areas of the city are flooded, particularly during tidal days. Flood risk management policy includes preparative measures for living with floods and to minimise the damage caused by floods as well as to take advantage of floods for sustainable development. An intensive literature review, including administrative reports as well as expert interviews have been undertaken to gain more insight into flood characteristics, their consequences and risk mitigation. Therefore, flood damaging processes and trends have been reviewed for Can Tho City and the Mekong Basin in Vietnam. Additionally, suitable flood damage estimation methodologies have been collected as important input for flood risk analyses. On this basis it has been investigated which flood risk mitigation and management strategies promise to be effective in Can Tho City, Vietnam.

  12. Vacuolar ATPase regulates surfactant secretion in rat alveolar type II cells by modulating lamellar body calcium.

    Directory of Open Access Journals (Sweden)

    Narendranath Reddy Chintagari

    Full Text Available Lung surfactant reduces surface tension and maintains the stability of alveoli. How surfactant is released from alveolar epithelial type II cells is not fully understood. Vacuolar ATPase (V-ATPase is the enzyme responsible for pumping H(+ into lamellar bodies and is required for the processing of surfactant proteins and the packaging of surfactant lipids. However, its role in lung surfactant secretion is unknown. Proteomic analysis revealed that vacuolar ATPase (V-ATPase dominated the alveolar type II cell lipid raft proteome. Western blotting confirmed the association of V-ATPase a1 and B1/2 subunits with lipid rafts and their enrichment in lamellar bodies. The dissipation of lamellar body pH gradient by Bafilomycin A1 (Baf A1, an inhibitor of V-ATPase, increased surfactant secretion. Baf A1-stimulated secretion was blocked by the intracellular Ca(2+ chelator, BAPTA-AM, the protein kinase C (PKC inhibitor, staurosporine, and the Ca(2+/calmodulin-dependent protein kinase II (CaMKII, KN-62. Baf A1 induced Ca(2+ release from isolated lamellar bodies. Thapsigargin reduced the Baf A1-induced secretion, indicating cross-talk between lamellar body and endoplasmic reticulum Ca(2+ pools. Stimulation of type II cells with surfactant secretagogues dissipated the pH gradient across lamellar bodies and disassembled the V-ATPase complex, indicating the physiological relevance of the V-ATPase-mediated surfactant secretion. Finally, silencing of V-ATPase a1 and B2 subunits decreased stimulated surfactant secretion, indicating that these subunits were crucial for surfactant secretion. We conclude that V-ATPase regulates surfactant secretion via an increased Ca(2+ mobilization from lamellar bodies and endoplasmic reticulum, and the activation of PKC and CaMKII. Our finding revealed a previously unrealized role of V-ATPase in surfactant secretion.

  13. 2D NUMERICAL SIMULATION OF FLOOD AND FLUVIAL PROCESS IN THE MEANDERING AND ISLAND-BRAIDED MIDDLE YANGTZE RIVER

    Institute of Scientific and Technical Information of China (English)

    Yong-jun LU; Zhao-yin WANG; Li-qin ZUO; Li-jun ZHU

    2005-01-01

    The characteristics of water flow and sediment transport in a typical meandering and island-braided reach of the middle Yangtze River is investigated using a two-dimensional (2D)mathematical model. The major problems studied in the paper include the carrying capacity for suspended load, the incipient velocity and transport formula of non-uniform sediment, the thickness of the mixed layer on the riverbed, and the partitioning of bed load and suspended load. The model parameters are calibrated using extensive field data. Water surface profiles, distribution of flow velocities, riverbed deformation are verified with site measurements. The model is applied to a meandering and island-braided section of the Wakouzi-Majiazui reach in the middle Yangtze River,which is about 200 km downstream from the Three Gorges Dam, to study the training scheme of the navigation channels. The model predicts the processes of sediment deposition and river bed erosion,changes of flow stage and navigation conditions for the first 20 years of impoundment of the Three Gorges Project.

  14. Composition, structure and mechanical properties define performance of pulmonary surfactant membranes and films.

    Science.gov (United States)

    Parra, Elisa; Pérez-Gil, Jesús

    2015-01-01

    The respiratory surface in the mammalian lung is stabilized by pulmonary surfactant, a membrane-based system composed of multiple lipids and specific proteins, the primary function of which is to minimize the surface tension at the alveolar air-liquid interface, optimizing the mechanics of breathing and avoiding alveolar collapse, especially at the end of expiration. The goal of the present review is to summarize current knowledge regarding the structure, lipid-protein interactions and mechanical features of surfactant membranes and films and how these properties correlate with surfactant biological function inside the lungs. Surfactant mechanical properties can be severely compromised by different agents, which lead to surfactant inhibition and ultimately contributes to the development of pulmonary disorders and pathologies in newborns, children and adults. A detailed comprehension of the unique mechanical and rheological properties of surfactant layers is crucial for the diagnostics and treatment of lung diseases, either by analyzing the contribution of surfactant impairment to the pathophysiology or by improving the formulations in surfactant replacement therapies. Finally, a short review is also included on the most relevant experimental techniques currently employed to evaluate lung surfactant mechanics, rheology, and inhibition and reactivation processes.

  15. Selective Antimicrobial Activities and Action Mechanism of Micelles Self-Assembled by Cationic Oligomeric Surfactants.

    Science.gov (United States)

    Zhou, Chengcheng; Wang, Fengyan; Chen, Hui; Li, Meng; Qiao, Fulin; Liu, Zhang; Hou, Yanbo; Wu, Chunxian; Fan, Yaxun; Liu, Libing; Wang, Shu; Wang, Yilin

    2016-02-17

    This work reports that cationic micelles formed by cationic trimeric, tetrameric, and hexameric surfactants bearing amide moieties in spacers can efficiently kill Gram-negative E. coli with a very low minimum inhibitory concentration (1.70-0.93 μM), and do not cause obvious toxicity to mammalian cells at the concentrations used. With the increase of the oligomerization degree, the antibacterial activity of the oligomeric surfactants increases, i.e., hexameric surfactant > tetrameric surfactant > trimeric surfactant. Isothermal titration microcalorimetry, scanning electron microscopy, and zeta potential results reveal that the cationic micelles interact with the cell membrane of E. coli through two processes. First, the integrity of outer membrane of E. coli is disrupted by the electrostatic interaction of the cationic ammonium groups of the surfactants with anionic groups of E. coli, resulting in loss of the barrier function of the outer membrane. The inner membrane then is disintegrated by the hydrophobic interaction of the surfactant hydrocarbon chains with the hydrophobic domains of the inner membrane, leading to the cytoplast leakage. The formation of micelles of these cationic oligomeric surfactants at very low concentration enables more efficient interaction with bacterial cell membrane, which endows the oligomeric surfactants with high antibacterial activity.

  16. Flood Impact Modelling and Natural Flood Management

    Science.gov (United States)

    Owen, Gareth; Quinn, Paul; ODonnell, Greg

    2016-04-01

    Local implementation of Natural Flood Management methods are now being proposed in many flood schemes. In principal it offers a cost effective solution to a number of catchment based problem as NFM tackles both flood risk and WFD issues. However within larger catchments there is the issue of which subcatchments to target first and how much NFM to implement. If each catchment has its own configuration of subcatchment and rivers how can the issues of flood synchronisation and strategic investment be addressed? In this study we will show two key aspects to resolving these issues. Firstly, a multi-scale network water level recorder is placed throughout the system to capture the flow concentration and travel time operating in the catchment being studied. The second is a Flood Impact Model (FIM), which is a subcatchment based model that can generate runoff in any location using any hydrological model. The key aspect to the model is that it has a function to represent the impact of NFM in any subcatchment and the ability to route that flood wave to the outfall. This function allows a realistic representation of the synchronisation issues for that catchment. By running the model in interactive mode the user can define an appropriate scheme that minimises or removes the risk of synchornisation and gives confidence that the NFM investment is having a good level of impact downstream in large flood events.

  17. Flood damage modelling: ambition and reality

    Science.gov (United States)

    Gerl, Tina; Kreibich, Heidi; Franco, Guillermo; Marechal, David; Schröter, Kai

    2015-04-01

    Flood damage modelling is of increasing importance for reliable risk assessment and management. Research efforts have improved the understanding of damaging processes and more sophisticated flood damage models have been developed. However, research seems to focus on a limited number of sectors and regions and validation of models still receives too little attention. We present a global inventory of flood damage models which is compiled from a review of scientific papers and research reports on flood damage models. The models are catalogued according to model specifications, geographical characteristics, sectors addressed, input variables used, model validation, transferability and model functions. The inventory is evaluated to position the current state of science and technology in flood damage modelling as well as to derive requirements for benchmarking damage models.

  18. Dynamic interfacial behavior of decyl methylnaphthalene sulfonate surfactants for enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Zhongkui; Ba Yan; Li Zongshi; Qiao Weihong; Cheng Luebai [State Key Lab. of Fine Chemicals, Dalian Univ. of Technology, Dalian (China)

    2004-10-01

    The high purity decyl methylnaphthalene sulfonate (DMNS) was synthesized, the purity was determined by HPLC and the structure was confirmed by IR, UV and ESI-MS. Dynamic interfacial tensions (DIT) between DMNS flooding systems and crude oil were measured and the effects of sodium carbonate concentration, surfactant concentration and sodium chloride concentration on the DIT behaviors were investigated. It's found that the surfactant concentration, alkali concentration and the salinity have obvious influences on DIT behaviors. DMNS possessed outstanding capacity and efficiency of lowering the DIT between oil and water. The minimum dynamic interfacial tension could reach 6.35 x 10{sup -6} mNm{sup -1} at a low concentration for added surfactant. DMNS might be used in Enhanced Oil Recovery with low costs and high efficiency. (orig.)

  19. Urban pluvial flood prediction

    DEFF Research Database (Denmark)

    Thorndahl, Søren Liedtke; Nielsen, Jesper Ellerbæk; Jensen, David Getreuer

    2016-01-01

    Flooding produced by high-intensive local rainfall and drainage system capacity exceedance can have severe impacts in cities. In order to prepare cities for these types of flood events – especially in the future climate – it is valuable to be able to simulate these events numerically both...... historically and in real-time. There is a rather untested potential in real-time prediction of urban floods. In this paper radar data observations with different spatial and temporal resolution, radar nowcasts of 0–2 h lead time, and numerical weather models with lead times up to 24 h are used as inputs...... to an integrated flood and drainage systems model in order to investigate the relative difference between different inputs in predicting future floods. The system is tested on a small town Lystrup in Denmark, which has been flooded in 2012 and 2014. Results show it is possible to generate detailed flood maps...

  20. REMOVAL OF ORGANIC CHEMICALS FROM WASTEWATER BY SURFACTANT SEPARATION

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2002-01-01

    This research presents a novel hybrid process for removing organic chemicals from contaminated water. The process uses surfactant to carry out two unit operations (1) Extraction; (2) Foam flotation. In the first step, surfactant is used to extract most of the amounts of organic contaminants in the stream. In the second step, foam flotation is used to further reduce organic contaminants and recover surfactant from the stream. The process combines the advantages of extraction and foam flotation, which allows the process not only to handle a wide range of organic contaminants, but also to effectively treat a wide range of the concentration of organic contaminants in the stream and reduce it to a very low level. Surfactant regeneration can be done by conventional methods. This process is simple and low cost. The wastes are recoverable. The objective of this research is to develop an environmentally innocuous process for the wastewater or reclaimed water treatment with the ability to handle a wide range of organic contaminants, also to effectively treat a wide range of the concentration of organic contaminants in contaminated water and reduce it to a very low level, finally, provides simpler, less energy cost and economically-practical process design. Another purpose is to promote the environmental concern in minority students and encourage minority students to become more involved in environmental engineering research.

  1. Final Report, Distillation Column Flooding Predictor

    Energy Technology Data Exchange (ETDEWEB)

    George E. Dzyacky

    2003-05-31

    The Flooding Predictor is an advanced process control strategy comprising a patented pattern-recognition methodology that identifies pre-flood patterns discovered to precede flooding events in distillation columns. The grantee holds a U.S. patent on the modeling system. The technology was validated at the Separations Research Program, The University of Texas at Austin under a grant from the U. S. Department of Energy, Inventions & Innovation Program. Distillation tower flooding occurs at abnormally high vapor and/or liquid rates. The loss in tray efficiencies is attributed to unusual behavior of liquid inventories inside the column leading to conditions of flooding of the space in between trays with liquid. Depending on the severity of the flood condition, consequences range from off spec products to equipment damage and tower shutdown. This non-intrusive pattern recognition methodology, processes signal data obtained from existing column instrumentation. Once the pattern is identified empirically, it is modeled and coded into the plant's distributed control system. The control system is programmed to briefly "unload" the tower each time the pattern appears. The unloading takes the form of a momentary reduction in column severity, e.g., decrease bottom temperature, reflux or tower throughput. Unloading the tower briefly at the pre-flood state causes long-term column operation to become significantly more stable - allowing an increase in throughput and/or product purity. The technology provides a wide range of value between optimization and flooding. When a distillation column is not running at capacity, it should be run in such a way ("pushed") that optimal product purity is achieved. Additional benefits include low implementation and maintenance costs, and a high level of console operator acceptance. The previous commercial applications experienced 98% uptime over a four-year period. Further, the technology is unique in its ability to distinguish between

  2. Surfactant recovery from water using foam fractionation

    Energy Technology Data Exchange (ETDEWEB)

    Tharapiwattananon, N.; Osuwan, S. [Chulalongkorn Univ., Bangkok (Thailand); Scamehorn, J.F. [Inst. of Oklahoma, Norman, OK (United States)] [and others

    1996-05-01

    The purpose of this study was to investigate the use of foam fractionation to recover surfactant from water. A simple continuous mode foam fractionation was used and three surfactants were studied (two anionic and one cationic). The effects of air flow rate, foam height, liquid height, liquid feed surfactant concentration, and sparger porosity were studied. This technique was shown to be effective in either surfactant recovery or the reduction of surfactant concentration in water to acceptable levels. As an example of the effectiveness of this technique, the cetylpyridinium chloride concentration in water can be reduced by 90% in one stage with a liquid residence time of 375 minutes. The surfactant concentration in the collapsed foam is 21.5 times the feed concentration. This cationic surfactant was easier to remove from water by foam fractionation than the anionic surfactants studied.

  3. Synthesis of carbohydrate-based surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Pemberton, Jeanne E.; Polt, Robin L.; Maier, Raina M.

    2016-11-22

    The present invention provides carbohydrate-based surfactants and methods for producing the same. Methods for producing carbohydrate-based surfactants include using a glycosylation promoter to link a carbohydrate or its derivative to a hydrophobic compound.

  4. Modeling on Flash Flood Disaster Induced by Bed Load

    Institute of Scientific and Technical Information of China (English)

    CAO Shuyou; LIU Xingnian; HUANG Er; YANG Keiun

    2008-01-01

    Flash floods result from a complex interaction among hydro-meteorological, hydrologi-cal, and hydraulic processes across various spatial and temporal scales. Sichuan Province suffers flash floods frequently owing to mountain weather and topography. A flash flood and gravel bed load transport are two key relative problems in mountain river engineering. Bed materials are often encountered in alternate scouring and deposition in mountain fluvial processes during a flash flood.In this circumstance, CRS-1 bed load numerical model jointly with scale physical model is em-ployed to predict water level and gravel bed scour and deposition for design of flood control dykes and flash flood disaster mitigation. A case study on the mechanism of a flash flood disaster in-duced by bed load transport for a hydropower station in Sichuan Province is conducted. Finally,suggestions to protect the hydropower station are proposed.

  5. Experimental study of chemical concentration variation of ASP flooding

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A physical modeling system of long slim tube was established. Several pressure measuring and sampling points were laid out at different positions along the tube. Through real-time measurements of pressures and chemical concentrations at different points, the mass transfer and chemical concentration of ASP flooding in porous media are studied. The concentration of chemicals declines gradually during the fluid flow from the inlet to the outlet of the model. The concentration increases in the front edge of the slug faster than the concentration decreases in the rear edge of the slug. The concentration variation of the chemicals is an asymmetrical and offset process. The order of motion velocities of the chemicals from fast to slow is polymer, alkali and surfactant. The motion lag and comprehensive diffusion are strong in the vicinity of the inlet, the motion velocities of the chemicals are high, the difference of flow velocities among the three chemicals is significant and the chromatographic separation of the chemicals is obvious. In the area near the outlet, the comprehensive diffusion and motion lag become weak, the concentrations of the chemicals decrease, the motion velocities of the chemicals are slow, the difference among the motion velocities of the chemicals becomes small, the chromatographic separation is not obvious, the adsorption and retention of chemicals gradually increase as the chemical slug moves further along the tube, the adsorption and retention of polymer is the most serious.

  6. Effects of Concentration and Conformation of Surfactants on Phase Separation of Surfactant-Water-Oil Systems

    Institute of Scientific and Technical Information of China (English)

    袁银权; 邹宪武; 刘昊阳

    2004-01-01

    The effects of surfactants on the phase separation of surfactant-water-oil systems have been investigated by using discontinuous molecular dynamic simulations. The phase separation speed and equilibrium configuration are dependent on the surfactant concentration and conformation. The equilibrium concentration of surfactants at the interface remains constant. With the increasing surfactant concentration, the equilibrium configuration crosses over from the disperse phase to the bicontinuous one. The crossover concentration is estimated. The conformation of the surfactant has little effect on the equilibrium concentration of surfactants at the interface,while it affects the equilibrium configuration after phase separation.

  7. Complex Formation Between Polyelectrolytes and Ionic Surfactants

    OpenAIRE

    1998-01-01

    The interaction between polyelectrolyte and ionic surfactant is of great importance in different areas of chemistry and biology. In this paper we present a theory of polyelectrolyte ionic-surfactant solutions. The new theory successfully explains the cooperative transition observed experimentally, in which the condensed counterions are replaced by ionic-surfactants. The transition is found to occur at surfactant densities much lower than those for a similar transition in non-ionic polymer-sur...

  8. 2 Dimensional Hydrodynamic Flood Routing Analysis on Flood Forecasting Modelling for Kelantan River Basin

    Directory of Open Access Journals (Sweden)

    Azad Wan Hazdy

    2017-01-01

    Full Text Available Flood disaster occurs quite frequently in Malaysia and has been categorized as the most threatening natural disaster compared to landslides, hurricanes, tsunami, haze and others. A study by Department of Irrigation and Drainage (DID show that 9% of land areas in Malaysia are prone to flood which may affect approximately 4.9 million of the population. 2 Dimensional floods routing modelling demonstrate is turning out to be broadly utilized for flood plain display and is an extremely viable device for evaluating flood. Flood propagations can be better understood by simulating the flow and water level by using hydrodynamic modelling. The hydrodynamic flood routing can be recognized by the spatial complexity of the schematization such as 1D model and 2D model. It was found that most of available hydrological models for flood forecasting are more focus on short duration as compared to long duration hydrological model using the Probabilistic Distribution Moisture Model (PDM. The aim of this paper is to discuss preliminary findings on development of flood forecasting model using Probabilistic Distribution Moisture Model (PDM for Kelantan river basin. Among the findings discuss in this paper includes preliminary calibrated PDM model, which performed reasonably for the Dec 2014, but underestimated the peak flows. Apart from that, this paper also discusses findings on Soil Moisture Deficit (SMD and flood plain analysis. Flood forecasting is the complex process that begins with an understanding of the geographical makeup of the catchment and knowledge of the preferential regions of heavy rainfall and flood behaviour for the area of responsibility. Therefore, to decreases the uncertainty in the model output, so it is important to increase the complexity of the model.

  9. Field note from Pakistan floods: Preventing future flood disasters

    Directory of Open Access Journals (Sweden)

    Marcus Oxley

    2011-04-01

    Full Text Available Unusually heavy monsoon rains in Northern Pakistan have caused disproportionate levels of extreme flooding and unprecedented flood losses across the entire Indus River basin. Extensive land use changes and environmental degradation in the uplands and lowlands of the river basin together with the construction of a “built environment” out of balance with the functioning, capacities, scale and limits of the local ecosystems have exposed millions of people to an increased risk of extreme #ooding. The catastrophic nature of the August #ooding provides a unique opportunity to fundamentally change Pakistan’s current socio-economic development path by incorporating disaster risk reduction and climate change measures into the post-disaster recovery process to rebuild a safer, more resilient nation. In January 2005 one hundred and sixty-eight nations adopted the Hyogo Framework for Action (HFA2005-2015 to bring about a “substantial reduction in disaster losses” by 2015. Despite this global initiative a series of major disasters, including the recent flooding in Pakistan, all indicate that we are not on track to achieve the substantial reduction of disaster losses. The following fieldnote considers what can be done to accelerate progress towards implementation of the Hyogo Framework, drawing on insights and lessons learnt from the August flooding to understand how Pakistan and neighbouring countries can prevent a repeat of such catastrophic disasters in future years.

  10. Hydrological simulation of flood transformations in the upper Danube River: Case study of large flood events

    Directory of Open Access Journals (Sweden)

    Mitková Veronika Bačová

    2016-12-01

    Full Text Available The problem of understand natural processes as factors that restrict, limit or even jeopardize the interests of human society is currently of great concern. The natural transformation of flood waves is increasingly affected and disturbed by artificial interventions in river basins. The Danube River basin is an area of high economic and water management importance. Channel training can result in changes in the transformation of flood waves and different hydrographic shapes of flood waves compared with the past. The estimation and evolution of the transformation of historical flood waves under recent river conditions is only possible by model simulations. For this purpose a nonlinear reservoir cascade model was constructed. The NLN-Danube nonlinear reservoir river model was used to simulate the transformation of flood waves in four sections of the Danube River from Kienstock (Austria to Štúrovo (Slovakia under relatively recent river reach conditions. The model was individually calibrated for two extreme events in August 2002 and June 2013. Some floods that occurred on the Danube during the period of 1991–2002 were used for the validation of the model. The model was used to identify changes in the transformational properties of the Danube channel in the selected river reach for some historical summer floods (1899, 1954 1965 and 1975. Finally, a simulation of flood wave propagation of the most destructive Danube flood of the last millennium (August 1501 is discussed.

  11. Evaluation of surfactant flushing for remediating EDC-tar contamination

    Science.gov (United States)

    Liang, Chenju; Hsieh, Cheng-Lin

    2015-06-01

    Ethylene dichloride tar (EDC-tar) is a dense non-aqueous phase liquid (DNAPL) waste originated from the process of vinyl chloride production, with major constituents including chlorinated aliphatic and aromatic hydrocarbons. This study investigated the feasibility of Surfactant Enhanced Aquifer Remediation (SEAR) for treating EDC-tar contaminated aquifers. Initial experiments explored the potential to enhance the apparent solubility of EDC-tar using single or mixed surfactants. The results showed that an aqueous solution mixed anionic and non-ionic surfactants (i.e., SDS/Tween 80) exhibited higher EDC-tar apparent solubility and lower surface tension than other surfactant systems tested. Additionally, alkaline pH aids in increasing the EDC-tar apparent solubility. In column flushing experiments, it was seen that the alkaline mixed SDS/Tween 80 solution showed better removal of pure EDC-tar from silica sand porous media. Furthermore, separation of EDC-tar in the surfactant solution was conducted employing a salting-out effect. Significant separation of DNAPL was observed when 13 wt.% or more NaCl was added to the solution. Overall, this study evaluates the feasibility of using SEAR for remediating EDC-tar contaminated subsurface soil and groundwater.

  12. Binding of cationic surfactants to humic substances

    NARCIS (Netherlands)

    Ishiguro, M.; Tan, W.; Koopal, L.K.

    2007-01-01

    Commercial surfactants are introduced into the environment either through waste products or site-specific contamination. The amphiphilic nature of both surfactants and humic substances (HS) leads to their mutual attraction especially when surfactant and HS are oppositely charged. Binding of the cati

  13. Surfactant analysis in oil-containing fluids

    Energy Technology Data Exchange (ETDEWEB)

    Gronsveld, J.; Faber, M.J. (Koninklijke Shell Exploratie en Produktie Laboratorium, Rijswijk (Netherlands))

    The total surfactant concentration in aqueous phase samples can be analysed with a potentiometric titration. In enhanced oil recovery research, however, the surfactant is produced not only in aqueous phase samples but also in oleic phase samples. The oleic constituents in the oliec phase samples interfere in the surfactant analysis and, therefore, the titration method has been adapted. (orig.).

  14. Surfactant adsorption to soil components and soils

    NARCIS (Netherlands)

    Ishiguro, Munehide; Koopal, Luuk K.

    2016-01-01

    Soils are complex and widely varying mixtures of organic matter and inorganic materials; adsorption of surfactants to soils is therefore related to the soil composition. We first discuss the properties of surfactants, including the critical micelle concentration (CMC) and surfactant adsorption on

  15. Mapping technological and biophysical capacities of watersheds to regulate floods

    Science.gov (United States)

    Mogollon, Beatriz; Villamagna, Amy M.; Frimpong, Emmanuel A.; Angermeier, Paul

    2016-01-01

    Flood regulation is a widely valued and studied service provided by watersheds. Flood regulation benefits people directly by decreasing the socio-economic costs of flooding and indirectly by its positive impacts on cultural (e.g., fishing) and provisioning (e.g., water supply) ecosystem services. Like other regulating ecosystem services (e.g., pollination, water purification), flood regulation is often enhanced or replaced by technology, but the relative efficacy of natural versus technological features in controlling floods has scarcely been examined. In an effort to assess flood regulation capacity for selected urban watersheds in the southeastern United States, we: (1) used long-term flood records to assess relative influence of technological and biophysical indicators on flood magnitude and duration, (2) compared the widely used runoff curve number (RCN) approach for assessing the biophysical capacity to regulate floods to an alternative approach that acknowledges land cover and soil properties separately, and (3) mapped technological and biophysical flood regulation capacities based on indicator importance-values derived for flood magnitude and duration. We found that watersheds with high biophysical (via the alternative approach) and technological capacities lengthened the duration and lowered the peak of floods. We found the RCN approach yielded results opposite that expected, possibly because it confounds soil and land cover processes, particularly in urban landscapes, while our alternative approach coherently separates these processes. Mapping biophysical (via the alternative approach) and technological capacities revealed great differences among watersheds. Our study improves on previous mapping of flood regulation by (1) incorporating technological capacity, (2) providing high spatial resolution (i.e., 10-m pixel) maps of watershed capacities, and (3) deriving importance-values for selected landscape indicators. By accounting for technology that enhances

  16. Remediation of sandy soils using surfactant solutions and foams.

    Science.gov (United States)

    Couto, Hudson J B; Massarani, Guilio; Biscaia, Evaristo C; Sant'Anna, Geraldo L

    2009-05-30

    Remediation of sandy soils contaminated with diesel oil was investigated in bench-scale experiments. Surfactant solution, regular foams and colloidal gas aphrons were used as remediation fluids. An experimental design technique was used to investigate the effect of relevant process variables on remediation efficiency. Soils prepared with different average particle sizes (0.04-0.12 cm) and contaminated with different diesel oil contents (40-80 g/kg) were used in experiments conducted with remediation fluids. A mathematical model was proposed allowing for the determination of oil removal rate-constant (k(v)) and oil content remaining in the soil after remediation (C(of)) as well as estimation of the percentage of oil removed. Oil removal efficiencies obtained under the central experimental design conditions were 96%, 88% and 35% for aphrons, regular foams and surfactant solutions, respectively. High removal efficiencies were obtained using regular foams and aphrons, demanding small amounts of surfactant.

  17. SCREENING METHODS FOR SELECTION OF SURFACTANT FORMULATIONS FOR IOR FROM FRACTURED CARBONATE RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    William A. Goddard III; Yongchun Tang; Patrick Shuler; Mario Blanco; Yongfu Wu; Seung Soon Jang

    2005-07-01

    This topical report presents details of the laboratory work performed to complete Task 1 of this project; developing rapid screening methods to assess surfactant performance for IOR (Improved Oil Recovery) from fractured carbonate reservoirs. The desired outcome is to identify surfactant formulations that increase the rate and amount of aqueous phase imbibition into oil-rich, oil-wet carbonate reservoir rock. Changing the wettability from oil-wet to water-wet is one key to enhancing this water-phase imbibition process that in turn recovers additional oil from the matrix portion of a carbonate reservoir. The common laboratory test to evaluate candidate surfactant formulations is to measure directly the aqueous imbibition rate and oil recovery from small outcrop or reservoir cores, but this procedure typically requires several weeks. Two methods are presented here for the rapid screening of candidate surfactant formulations for their potential IOR performance in carbonate reservoirs. One promising surfactant screening protocol is based on the ability of a surfactant solution to remove aged crude oil that coats a clear calcite crystal (Iceland Spar). Good surfactant candidate solutions remove the most oil the quickest from the chips, plus change the apparent contact angle of the remaining oil droplets on the surface that thereby indicate increased water-wetting. The other fast surfactant screening method is based on the flotation behavior of powdered calcite in water. In this test protocol, first the calcite power is pre-treated to make the surface oil-wet. The next step is to add the pre-treated powder to a test tube and add a candidate aqueous surfactant formulation; the greater the percentage of the calcite that now sinks to the bottom rather than floats, the more effective the surfactant is in changing the solids to become now preferentially water-wet. Results from the screening test generally are consistent with surfactant performance reported in the literature.

  18. Persurf, a new method to improve surfactant delivery: a study in surfactant depleted rats.

    Directory of Open Access Journals (Sweden)

    Wolfram Burkhardt

    Full Text Available PURPOSE: Exogenous surfactant is not very effective in adults with ARDS, since surfactant does not reach atelectatic alveoli. Perfluorocarbons (PFC can recruit atelectatic areas but do not replace impaired endogenous surfactant. A surfactant-PFC-mixture could combine benefits of both therapies. The aim of the proof-of-principal-study was to produce a PFC-in-surfactant emulsion (Persurf and to test in surfactant depleted Wistar rats whether Persurf achieves I. a more homogenous pulmonary distribution and II. a more homogenous recruitment of alveoli when compared with surfactant or PFC alone. METHODS: Three different PFC were mixed with surfactant and phospholipid concentration in the emulsion was measured. After surfactant depletion, animals either received 30 ml/kg of PF5080, 100 mg/kg of stained (green dye Curosurf™ or 30 ml/kg of Persurf. Lungs were fixated after 1 hour of ventilation and alveolar aeration and surfactant distribution was estimated by a stereological approach. RESULTS: Persurf contained 3 mg/ml phospholipids and was stable for more than 48 hours. Persurf-administration improved oxygenation. Histological evaluation revealed a more homogenous surfactant distribution and alveolar inflation when compared with surfactant treated animals. CONCLUSIONS: In surfactant depleted rats administration of PFC-in-surfactant emulsion leads to a more homogenous distribution and aeration of the lung than surfactant alone.

  19. Flood regimes in a changing world: What do we know?

    Science.gov (United States)

    Bloeschl, G.

    2015-12-01

    There has been a surprisingly large number of major floods in the last years around the world which suggests that floods may have increased and will continue to increase in the next decades. However, the realism of such changes is still hotly discussed in the literature. In this presentation I will argue that a fresh look is needed at the flood change problem in terms of the causal factors including river training, land use changes and climate variability. Analysing spatial patterns of dynamic flood characteristics helps learn form the rich diversity of flood processes across the landscape. I will present a number of examples across Europe to illustrate the range of flood generation processes and the causal factors of changes in the flood regime. On the basis of these examples, I will demonstrate how comparative hydrology can assist in learning from the differences of flood characteristics between catchments both for present and future conditions. Focus on the interactions of the natural and human water system will be instrumental in making meaningful statements about future floods in a changing world. References Hall et al. (2014) Understanding Flood Regime Changes in Europe: A state of the art assessment. Hydrol. Earth Sys. Sc., 18, 2735-2772. Blöschl et al. (2015) Increasing river floods: fiction or reality? Wiley Interdisciplinary Reviews: Water. doi: 10.1002/wat2.1079

  20. BDHI: a French national database on historical floods

    Directory of Open Access Journals (Sweden)

    Lang Michel

    2016-01-01

    Full Text Available The paper describes the various features of the BDHI database (objects, functions, content. This document database provides document sheets on historical floods from various sources: technical reports from water authorities, scientific accounts (meteorology, hydrology, hydraulics..., post-disaster reports, newspapers or book extracts... It is complemented by fact sheets on flood events, which provide a summary text on significant past floods: location, date and duration, type of flood, extent, probability, adverse consequences A search engine is provided for information search based on time (specific date or period, on location (district, basin, city or thematic topic (document type, flood type, flood magnitude, flood impact.... We conclude by some future challenges in relation to the next cycle of the Floods Directive (2016-2022, with the inventory of past floods which had significant adverse impacts. What are the flood events that need to be integrated (new ones later than 2011 and/or previous floods that had not yet been selected? How can the process of historical data integration be extended at a local scale, with an adequate process of validation? How to promote the use of BDHI database in relation with the development of the culture of risk?

  1. Evaporation of Sessile Droplets Laden with Particles and Insoluble Surfactants.

    Science.gov (United States)

    Karapetsas, George; Chandra Sahu, Kirti; Matar, Omar K

    2016-07-12

    We consider the flow dynamics of a thin evaporating droplet in the presence of an insoluble surfactant and noninteracting particles in the bulk. On the basis of lubrication theory, we derive a set of evolution equations for the film height, the interfacial surfactant, and bulk particle concentrations, taking into account the dependence of liquid viscosity on the local particle concentration. An important ingredient of our model is that it takes into account the fact that the surfactant adsorbed at the interface hinders evaporation. We perform a parametric study to investigate how the presence of surfactants affects the evaporation process as well as the flow dynamics with and without the presence of particles in the bulk. Our numerical calculations show that the droplet lifetime is affected significantly by the balance between the ability of the surfactant to enhance spreading, suppressing the effect of thermal Marangoni stresses-induced motion, and to hinder the evaporation flux through the reduction of the effective interfacial area of evaporation, which tend to accelerate and decelerate the evaporation process, respectively. For particle-laden droplets and in the case of dilute solutions, the droplet lifetime is found to be weakly dependent on the initial particle concentration. We also show that the particle deposition patterns are influenced strongly by the direct effect of the surfactant on the evaporative flux; in certain cases, the "coffee-stain" effect is enhanced significantly. A discussion of the delicate interplay between the effects of capillary pressure and solutal and thermal Marangoni stresses, which drive the liquid flow inside of the evaporating droplet giving rise to the observed results, is provided herein.

  2. Assessment of surfactant use in preterm infants as a marker of neonatal intensive care unit quality

    Directory of Open Access Journals (Sweden)

    Lorch Scott A

    2011-01-01

    Full Text Available Abstract Background Proposed neonatal quality measures have included structural measures such as average daily census, and outcome measures such as mortality and rates of complications of prematurity. However, process measures have remained largely unexamined. The objective of this research was to examine variation in surfactant use as a possible process measure of neonatal quality. Methods We obtained data on infants 30 to 34 weeks gestation admitted with respiratory distress syndrome (RDS within 48 hours of birth to 16 hospitals participating in the Pediatric Health Information Systems database from 2001-2006. Models were developed to describe hospital variation in surfactant use and identify patient and hospital predictors of use. Another cohort of all infants admitted within 24 hours of birth was used to obtain adjusted neonatal intensive care unit (NICU mortality rates. To assess the construct validity of surfactant use as a quality metric, adjusted hospital rates of mortality and surfactant use were compared using Kendall's tau. Results Of 3,633 infants, 46% received surfactant. For individual hospitals, the adjusted odds of surfactant use varied from 2.2 times greater to 5.9 times less than the hospital with the median adjusted odds of surfactant use. Increased annual admissions of extremely low birth weight infants to the NICU were associated with greater surfactant use (OR 1.80, 95% CI 1.02-3.19. The correlation between adjusted hospital rates of surfactant use and in-hospital mortality was 0.37 (Kendall's tau p = 0.051. Conclusions Though results were encouraging, efforts to examine surfactant use in infants with RDS as a process measure reflecting quality of care revealed significant challenges. Difficulties related to adequate measurement including defining RDS using administrative data, accounting for care received prior to transfer, and adjusting for severity of illness will need to be addressed to improve the utility of this

  3. RASOR flood modelling

    Science.gov (United States)

    Beckers, Joost; Buckman, Lora; Bachmann, Daniel; Visser, Martijn; Tollenaar, Daniel; Vatvani, Deepak; Kramer, Nienke; Goorden, Neeltje

    2015-04-01

    Decision making in disaster management requires fast access to reliable and relevant information. We believe that online information and services will become increasingly important in disaster management. Within the EU FP7 project RASOR (Rapid Risk Assessment and Spatialisation of Risk) an online platform is being developed for rapid multi-hazard risk analyses to support disaster management anywhere in the world. The platform will provide access to a plethora of GIS data that are relevant to risk assessment. It will also enable the user to run numerical flood models to simulate historical and newly defined flooding scenarios. The results of these models are maps of flood extent, flood depths and flow velocities. The RASOR platform will enable to overlay historical event flood maps with observations and Earth Observation (EO) imagery to fill in gaps and assess the accuracy of the flood models. New flooding scenarios can be defined by the user and simulated to investigate the potential impact of future floods. A series of flood models have been developed within RASOR for selected case study areas around the globe that are subject to very different flood hazards: • The city of Bandung in Indonesia, which is prone to fluvial flooding induced by heavy rainfall. The flood hazard is exacerbated by land subsidence. • The port of Cilacap on the south coast of Java, subject to tsunami hazard from submarine earthquakes in the Sunda trench. • The area south of city of Rotterdam in the Netherlands, prone to coastal and/or riverine flooding. • The island of Santorini in Greece, which is subject to tsunamis induced by landslides. Flood models have been developed for each of these case studies using mostly EO data, augmented by local data where necessary. Particular use was made of the new TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) product from the German Aerospace centre (DLR) and EADS Astrium. The presentation will describe the flood models and the

  4. Physical properties of botanical surfactants.

    Science.gov (United States)

    Müller, Lillian Espíndola; Schiedeck, Gustavo

    2017-08-24

    Some vegetal species have saponins in their composition with great potential to be used as natural surfactants in organic crops. This work aims to evaluate some surfactants physical properties of Quillaja brasiliensis and Agave angustifolia, based on different methods of preparation and concentration. The vegetal samples were prepared by drying and grinding, frozen and after chopped or used fresh and chopped. The neutral bar soap was used as a positive control. The drying and grinding of samples were the preparation method that resulted in higher foam column height in both species but Q. brasiliensis was superior to A. angustifolia in all comparisons and foam index was 2756 and 1017 respectively. Critical micelle concentration of Q. brasiliensis was 0.39% with the superficial tension of 54.40mNm(-1) while neutral bar soap was 0.15% with 34.96mNm(-1). Aspects such as genetic characteristics of the species, environmental conditions, and analytical methods make it difficult to compare the results with other studies, but Q. brasiliensis powder has potential to be explored as a natural surfactant in organic farming. Not only the surfactants physical properties of botanical saponins should be taken into account but also its effect on insects and diseases control when decided using them. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Interactions of Ovalbumin with Ionic Surfactants

    Institute of Scientific and Technical Information of China (English)

    GUO Xia; YAN Hui; GUO Rong

    2008-01-01

    The interactions of ovalbumin (OVA) with one anionic surfactant,sodium dodecyl sulfate (SDS),and two cationic surfactants,dodecyl trimethylammonium bromide (DTAB) and cetyl trimethylammonium bromide (CTAB),in water have been studied through fluorescence and UV-Vis spectroscopies and transmission electronic microscopy,combined with the measurement of conductivity.OVA can increase the critical micelle concentrations (cmc) of SDS and CTAB but has little effect on that of DTAB.The interaction between surfactant monomer and OVA is greater than that between surfactant micelles and OVA.Moreover,SDS can make OVA unfolded while cationic surfactants cannot.

  6. Surfactant gene polymorphisms and interstitial lung diseases

    Directory of Open Access Journals (Sweden)

    Pantelidis Panagiotis

    2001-11-01

    Full Text Available Abstract Pulmonary surfactant is a complex mixture of phospholipids and proteins, which is present in the alveolar lining fluid and is essential for normal lung function. Alterations in surfactant composition have been reported in several interstitial lung diseases (ILDs. Furthermore, a mutation in the surfactant protein C gene that results in complete absence of the protein has been shown to be associated with familial ILD. The role of surfactant in lung disease is therefore drawing increasing attention following the elucidation of the genetic basis underlying its surface expression and the proof of surfactant abnormalities in ILD.

  7. Connections between winter snowpack and subsequent spring floods in Norway

    Science.gov (United States)

    Schlichting, Lena; Engeland, Kolbjørn; Holmqvist, Erik; Bache Stranden, Heidi

    2016-04-01

    In Norway many inland and mountainous catchments have a hydrological regime where snow accumulates during winter. The runoff is delayed until the snow melts during spring. These processes are important for flood forecasting and water resource management, such as operation of hydropower reservoirs. It is commonly assumed that spring flood volume and peak linked to antecedent conditions such as winter snowpack, i.e. a large winter snowpack results in a high spring flood. The aims of this study are (i) to identify for which catchments a high correlation between snow water equivalent (SWE) at the end of the snow accumulation season and the subsequent spring flood, and (ii) establish regression models for these catchments to be used for seasonal flood forecasting. Daily runoff data from 43 distributed catchments all over Norway, each with at least 50 years of observations and a flood regime which is significantly influenced by snowmelt, were used. For each of these catchments we extracted SWE, precipitation and temperature on daily resolution from the on gridded data of Senorge.no. A peak-over-threshold approach was used to select independent flood events above the 90-th percentile. Maximum discharge, duration and volume were calculated for each event. The contribution of rain and snowmelt to each flood was additionally determined, based on snowmelt, precipitation and temperature data. The spring flood was defined as the first flood event that occurs after the date of maximum SWE, and the snowmelt contribution of at least 70%. The contribution of rain to a spring flood is independent of maximum SWE, resulting in a weaker correlation between maximum SWE and spring flood size. We therefore scaled the flood with the percentage of snow contribution to the flood event in order to adjust for the contribution from rain. The correlations between SWE and the spring flood were higher for scaled spring floods than for the unscaled ones. The results show for half of the stations a

  8. Investigations into surfactant/gas hydrate relationship

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, Rudy; Zhang, Guochang; Dearman, Jennifer; Woods, Charles [Swalm School of Chemical Engineering, Mississippi State University, Mississippi State, MS 39762 (United States)

    2007-03-15

    Gas hydrates have unique physical properties portending useful industrial applications of gas storage, gas separation, or water desalination. When gas hydrates were found in the early 1990s to occur naturally and abundantly in seafloors, three other primary interests and concerns emerged: potential new energy source, climate threat from their greenhouse gases, and seafloor instabilities. This paper presents research showing how anionic synthetic surfactants helped develop an industrial gas hydrate storage process for natural gas and how naturally-occurring in-situ anionic biosurfactants influence the formation and placement of gas hydrates in ocean sediments. The catalytic effects, mechanisms, and surface specificities imparted by synthetic surfactants in the gas storage process and imparted by biosurfactants in porous media are discussed. The Bacillus subtilis bacterium that is indigenous to gas hydrate mounds in the Gulf of Mexico was cultured in the laboratory. Its biosurfactant was separated and found to catalyze gas hydrates in porous media. The experiments indicate that seafloor-biosurfactants can be produced rapidly in-situ to achieve threshold concentrations whereby hydrates are promoted. The biosurfactants accumulate and promote hydrate formation on specific mineral surfaces such as sodium montmorillonite. (author)

  9. SERVIR-Africa: Developing an Integrated Platform for Floods Disaster Management in Africa

    Science.gov (United States)

    Macharia, Daniel; Korme, Tesfaye; Policelli, Fritz; Irwin, Dan; Adler, Bob; Hong, Yang

    2010-01-01

    SERVIR-Africa is an ambitious regional visualization and monitoring system that integrates remotely sensed data with predictive models and field-based data to monitor ecological processes and respond to natural disasters. It aims addressing societal benefits including floods and turning data into actionable information for decision-makers. Floods are exogenous disasters that affect many parts of Africa, probably second only to drought in terms of social-economic losses. This paper looks at SERVIR-Africa's approach to floods disaster management through establishment of an integrated platform, floods prediction models, post-event flood mapping and monitoring as well as flood maps dissemination in support of flood disaster management.

  10. MicroRNA-206 regulates surfactant secretion by targeting VAMP-2.

    Science.gov (United States)

    Zhang, Honghao; Guo, Yujie; Mishra, Amarjit; Gou, Deming; Chintagari, Narendranath Reddy; Liu, Lin

    2015-01-01

    Lung surfactant secretion is a highly regulated process. Our previous studies have shown that VAMP-2 is essential for surfactant secretion. In the present study we investigated the role of miR-206 in surfactant secretion through VAMP-2. VAMP-2 was confirmed to be a target of miR-206 by 3'-untranslational region (3'-UTR) luciferase assay. Mutations in the predicated miR-206 binding sites reduced the binding of miR-206 to the 3'-UTR of VAMP-2. miR-206 decreased the expression of VAMP-2 protein and decreased the lung surfactant secretion in alveolar type II cells. In conclusion, miR-206 regulates lung surfactant secretion by limiting the availability of VAMP-2 protein.

  11. Modification of nano-sized layered double hydroxides by long-chain organic aliphatic surfactants

    Directory of Open Access Journals (Sweden)

    RAMASAMY ANBARASAN

    2008-03-01

    Full Text Available The inter-layer anion of layered double hydroxides (LDH with a hydrotalcite (HT-like structure was ion-exchanged with various organic surfactants, particularly with long chain aliphatic surfactants. After the ion-exchange process, the basal spacing of the LDH was increased and the increase of the basal spacing depended on various factors, such as the intercalation capacity functionality and orientation capability of the surfactant. Of the employed surfactants, stearic acid intercalated LDH showed the highest increase of the basal spacing, which was confirmed by XRD analysis. FTIR results supported the interaction of the surfactants with the LDH. In addition, an increase in the thermal stability of the dodecanedioic acid intercalated HT was evidenced by the TGA method.

  12. Long-term experiences with pluvial flood risk management

    Directory of Open Access Journals (Sweden)

    Fritsch Kathrina

    2016-01-01

    Full Text Available The awareness of pluvial (rain-related flood risk has grown significantly in the past few years but pluvial flooding is not handled with the same intensity throughout Europe. A variety of methods and modelling technologies are used to assess pluvial flood hazard and risk and to develop suggestions for flood mitigation measures. A brief overview of current model approaches is followed by the description of a modelling methodology that has been developed throughout the last 15 years with the focus on processing large scale areas. Experiences from several projects show that only high quality models of whole catchment areas yield results with enough accuracy to gain credibility among stakeholders, planners and the public. As a best practice example shows, the model approach also helps to plan effective decentral flood protection measures. To ensure successful flood risk management, a long-term preservation of flood risk awareness among local authorities and the public is necessary.

  13. Communicating Flood Risk with Street-Level Data

    Science.gov (United States)

    Sanders, B. F.; Matthew, R.; Houston, D.; Cheung, W. H.; Karlin, B.; Schubert, J.; Gallien, T.; Luke, A.; Contreras, S.; Goodrich, K.; Feldman, D.; Basolo, V.; Serrano, K.; Reyes, A.

    2015-12-01

    Coastal communities around the world face significant and growing flood risks that require an accelerating adaptation response, and fine-resolution urban flood models could serve a pivotal role in enabling communities to meet this need. Such models depict impacts at the level of individual buildings and land parcels or "street level" - the same spatial scale at which individuals are best able to process flood risk information - constituting a powerful tool to help communities build better understandings of flood vulnerabilities and identify cost-effective interventions. To measure understanding of flood risk within a community and the potential impact of street-level models, we carried out a household survey of flood risk awareness in Newport Beach, California, a highly urbanized coastal lowland that presently experiences nuisance flooding from high tides, waves and rainfall and is expected to experience a significant increase in flood frequency and intensity with climate change. Interviews were completed with the aid of a wireless-enabled tablet device that respondents could use to identify areas they understood to be at risk of flooding and to view either a Federal Emergency Management Agency (FEMA) flood map or a more detailed map prepared with a hydrodynamic urban coastal flood model (UCI map) built with grid cells as fine as 3 m resolution and validated with historical flood data. Results indicate differences in the effectiveness of the UCI and FEMA maps at communicating the spatial distribution of flood risk, gender differences in how the maps affect flood understanding, and spatial biases in the perception of flood vulnerabilities.

  14. The role of surfactant treatment in preterm infants and term newborns with acute respiratory distress syndrome.

    Science.gov (United States)

    Wirbelauer, J; Speer, C P

    2009-05-01

    Surfactant treatment in preterm infants and term newborns with (acute respiratory distress syndrome) ARDS-like severe respiratory failure has become part of an individualized treatment strategy in many intensive care units around the world. These babies constitute heterogeneous groups of gestational ages, lung maturity, as well as of the underlying disease processes and postnatal interventions. The pathophysiology of respiratory failure in preterm infants is characterized by a combination of primary surfactant deficiency and surfactant inactivation as a result of plasma proteins leaking into the airways from areas of epithelial disruption and injury. Various pre- and postnatal factors, such as exposure to chorioamnionitis, pneumonia, sepsis and asphyxia, induce an injurious inflammatory response in the lungs of preterm infants, which may subsequently affect surfactant function, synthesis and alveolar stability. Surfactant inactivation--and dysfunction--is also a hallmark in newborns with meconium aspiration syndrome (MAS), pneumonia and other disorders affecting the pulmonary function. Although for the majority of suggested indications no data from randomized controlled trials exist, a surfactant replacement that counterbalances surfactant inactivation seems to improve oxygenation and lung function in many babies with ARDS without any apparent negative side effects. Newborns with MAS will definitely benefit from a reduced need for extracorporeal membrane oxygenation (ECMO). Clinical experience seems to justify surfactant treatment in neonates with ARDS.

  15. Anaerobic digestion of aircraft deicing fluid wastes: interactions and toxicity of corrosion inhibitors and surfactants.

    Science.gov (United States)

    Gruden, Cyndee L; Hernandez, Mark

    2002-01-01

    Corrosion inhibitors and surfactants are present in aircraft deicing fluids (ADFs) at significant concentrations (> 1% w/w). The purpose of this research was to study the interactions of a common nonionic surfactant with the commercially significant corrosion inhibitors used in modern ADF (4- and 5-methylbenzotriazole [MeBT]), and to determine the effects of their mixture on the conventional anaerobic digestion process. In mesophilic anaerobic microcosms codigesting wastewater solids, propylene glycol, and MeBT, increasing surfactant levels resulted in enhanced MeBT sorption on digester solids. As judged by anaerobic toxicity assays, responses from digesters containing surfactant concentrations below their critical micelle concentration (CMC) suggested that low nonionic surfactant concentrations could facilitate a reduction in the apparent toxicity of MeBT. In microcosms exposed to surfactant concentrations above their CMC, no increase in MeBT solubility was observed, and the anaerobic toxicity response corresponded to control systems not containing surfactant. Direct microscopic measurements of digesting biomass using fluorescent phylogenetic probes (fluorescent in situ hybridization) revealed that members of the domain Bacteria were more sensitive to MeBT in the presence of surfactant than were members of the domain Archaea.

  16. Flood risk assessment and associated uncertainty

    Directory of Open Access Journals (Sweden)

    H. Apel

    2004-01-01

    Full Text Available Flood disaster mitigation strategies should be based on a comprehensive assessment of the flood risk combined with a thorough investigation of the uncertainties associated with the risk assessment procedure. Within the 'German Research Network of Natural Disasters' (DFNK the working group 'Flood Risk Analysis' investigated the flood process chain from precipitation, runoff generation and concentration in the catchment, flood routing in the river network, possible failure of flood protection measures, inundation to economic damage. The working group represented each of these processes by deterministic, spatially distributed models at different scales. While these models provide the necessary understanding of the flood process chain, they are not suitable for risk and uncertainty analyses due to their complex nature and high CPU-time demand. We have therefore developed a stochastic flood risk model consisting of simplified model components associated with the components of the process chain. We parameterised these model components based on the results of the complex deterministic models and used them for the risk and uncertainty analysis in a Monte Carlo framework. The Monte Carlo framework is hierarchically structured in two layers representing two different sources of uncertainty, aleatory uncertainty (due to natural and anthropogenic variability and epistemic uncertainty (due to incomplete knowledge of the system. The model allows us to calculate probabilities of occurrence for events of different magnitudes along with the expected economic damage in a target area in the first layer of the Monte Carlo framework, i.e. to assess the economic risks, and to derive uncertainty bounds associated with these risks in the second layer. It is also possible to identify the contributions of individual sources of uncertainty to the overall uncertainty. It could be shown that the uncertainty caused by epistemic sources significantly alters the results

  17. Increasing river floods: fiction or reality?

    Science.gov (United States)

    Blöschl, Günter; Gaál, Ladislav; Hall, Julia; Kiss, Andrea; Komma, Jürgen; Nester, Thomas; Parajka, Juraj; Perdigão, Rui A P; Plavcová, Lenka; Rogger, Magdalena; Salinas, José Luis; Viglione, Alberto

    2015-01-01

    There has been a surprisingly large number of major floods in the last years around the world, which suggests that floods may have increased and will continue to increase in the next decades. However, the realism of such changes is still hotly discussed in the literature. This overview article examines whether floods have changed in the past and explores the driving processes of such changes in the atmosphere, the catchments and the river system based on examples from Europe. Methods are reviewed for assessing whether floods may increase in the future. Accounting for feedbacks within the human-water system is important when assessing flood changes over lead times of decades or centuries. It is argued that an integrated flood risk management approach is needed for dealing with future flood risk with a focus on reducing the vulnerability of the societal system. WIREs Water 2015, 2:329-344. doi: 10.1002/wat2.1079 For further resources related to this article, please visit the WIREs website.

  18. NASA Global Flood Mapping System

    Science.gov (United States)

    Policelli, Fritz; Slayback, Dan; Brakenridge, Bob; Nigro, Joe; Hubbard, Alfred

    2017-01-01

    Product utility key factors: Near real time, automated production; Flood spatial extent Cloudiness Pixel resolution: 250m; Flood temporal extent; Flash floods short duration on ground?; Landcover--Water under vegetation cover vs open water

  19. An anionic surfactant for EOR applications

    Science.gov (United States)

    Sagir, Muhammad; Tan, Isa M.; Mushtaq, Muhammad

    2014-10-01

    This work is to investigate the new anionic surfactants for the Enhanced Oil Recovery (EOR) application. Sulfonated anionic surfactant was produced by attaching SO3 to an ethoxylated alcohol to increase the performance of the surfactant. Methallyl chloride and ethoxylated alcohol was reacted followed by the reaction with sodium bisulfite to produce anionic sulfonated surfactant in 80.3 % yield. The sulfonation reaction parameters such as reactants mole ratio, reaction temperature and catalyst amount were optimized. The generation and stability of foam from the synthesized surfactant is also tested and results are reported. The synthesized novel surfactant was further investigated for the effect on the CO2 mobility in porous media and the findings are presented here. This in house developed surfactant has a great potential for CO2- EOR applications.

  20. Evaluation of various modelling approaches in flood routing simulation and flood area mapping

    Science.gov (United States)

    Papaioannou, George; Loukas, Athanasios; Vasiliades, Lampros; Aronica, Giuseppe

    2016-04-01

    An essential process of flood hazard analysis and mapping is the floodplain modelling. The selection of the modelling approach, especially, in complex riverine topographies such as urban and suburban areas, and ungauged watersheds may affect the accuracy of the outcomes in terms of flood depths and flood inundation area. In this study, a sensitivity analysis implemented using several hydraulic-hydrodynamic modelling approaches (1D, 2D, 1D/2D) and the effect of modelling approach on flood modelling and flood mapping was investigated. The digital terrain model (DTMs) used in this study was generated from Terrestrial Laser Scanning (TLS) point cloud data. The modelling approaches included 1-dimensional hydraulic-hydrodynamic models (1D), 2-dimensional hydraulic-hydrodynamic models (2D) and the coupled 1D/2D. The 1D hydraulic-hydrodynamic models used were: HECRAS, MIKE11, LISFLOOD, XPSTORM. The 2D hydraulic-hydrodynamic models used were: MIKE21, MIKE21FM, HECRAS (2D), XPSTORM, LISFLOOD and FLO2d. The coupled 1D/2D models employed were: HECRAS(1D/2D), MIKE11/MIKE21(MIKE FLOOD platform), MIKE11/MIKE21 FM(MIKE FLOOD platform), XPSTORM(1D/2D). The validation process of flood extent achieved with the use of 2x2 contingency tables between simulated and observed flooded area for an extreme historical flash flood event. The skill score Critical Success Index was used in the validation process. The modelling approaches have also been evaluated for simulation time and requested computing power. The methodology has been implemented in a suburban ungauged watershed of Xerias river at Volos-Greece. The results of the analysis indicate the necessity of sensitivity analysis application with the use of different hydraulic-hydrodynamic modelling approaches especially for areas with complex terrain.

  1. Flood management: prediction of microbial contamination in large-scale floods in urban environments.

    Science.gov (United States)

    Taylor, Jonathon; Lai, Ka Man; Davies, Mike; Clifton, David; Ridley, Ian; Biddulph, Phillip

    2011-07-01

    With a changing climate and increased urbanisation, the occurrence and the impact of flooding is expected to increase significantly. Floods can bring pathogens into homes and cause lingering damp and microbial growth in buildings, with the level of growth and persistence dependent on the volume and chemical and biological content of the flood water, the properties of the contaminating microbes, and the surrounding environmental conditions, including the restoration time and methods, the heat and moisture transport properties of the envelope design, and the ability of the construction material to sustain the microbial growth. The public health risk will depend on the interaction of these complex processes and the vulnerability and susceptibility of occupants in the affected areas. After the 2007 floods in the UK, the Pitt review noted that there is lack of relevant scientific evidence and consistency with regard to the management and treatment of flooded homes, which not only put the local population at risk but also caused unnecessary delays in the restoration effort. Understanding the drying behaviour of flooded buildings in the UK building stock under different scenarios, and the ability of microbial contaminants to grow, persist, and produce toxins within these buildings can help inform recovery efforts. To contribute to future flood management, this paper proposes the use of building simulations and biological models to predict the risk of microbial contamination in typical UK buildings. We review the state of the art with regard to biological contamination following flooding, relevant building simulation, simulation-linked microbial modelling, and current practical considerations in flood remediation. Using the city of London as an example, a methodology is proposed that uses GIS as a platform to integrate drying models and microbial risk models with the local building stock and flood models. The integrated tool will help local governments, health authorities

  2. ON EFFECT OF HAZARD MAP ON CONS CIOUSNESS OF FLOOD DISASTER PREVENSION OF RESIDENTS WHO EXPERIENCED FLOOD RECENTLY

    Science.gov (United States)

    Asai, Koji; Koga, Syota; Sakakibara, Hiroyuki

    In this paper, the effect of the flood hazard map distributed to the residents who experienced flood disasters recently and an effective method for improving consciousness of flood di saster prevention are discussed. The questionnaire surveys were conducted on the residents living in the middle basin of the Nishiki River, Iwakuni city, Yamaguchi Prefecture, before and after the distribution of the hazard map. It is found from this investigation that "knowledge", "att achment", and "crisis", are the main factors in the psychological process related to the flood prevention behavior. The effect of the distribution of the hazard map is judged from the probability of the flood prevention behavior. In addition, it is also found that "knowledge", "flood experiment of T0514", "crisis", "eff ectiveness", "load", and "easy reading of the hazard map", are keys to improve the cons ciousness of flood di saster prevention.

  3. Removal of Organic Dyes from Aqueous Solutions with Surfactant-Modified Magnetic Nanoparticles

    Directory of Open Access Journals (Sweden)

    Wybieralska Katarzyna

    2014-06-01

    Full Text Available The paper presents the results of studies on the possibility of using magnetic nanoparticles modified with selected hydrophobic surfactants for model post-production water purification. Colloidal solutions of iron hydroxide (III and iron oxide (II and III were obtained and their particles were subjected to surface modification using surfactants. Thus obtained magnetic fluids were used as active agents in the process of removing selected organic dyes from their aqueous solutions. The effectiveness of the modified compounds was analysed using spectrophotometric methods. It has been shown that the effectiveness of the process depends on the type of surfactant used to modify selected magnetic nanoparticles.

  4. Coupling the Alkaline-Surfactant-Polymer Technology and the Gelation Technology to Maximize Oil Production

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson; Phil Dowling; David Stewart; Bill Jones

    2005-12-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or reservoirs with different sand lenses with high permeability contrast. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more crude oil than waterflooding froin swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or reservoirs with high permeability contrast zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. Fluid-fluid interaction with different gel chemical compositions and alkaline-surfactant-polymer solution with pH values ranging from 9.2 to 12.9 have been tested. Aluminum-polyacrylamide gels are not stable to alkaline-surfactant-polymer solutions at any pH. Chromium-polyacrylamide gels with polymer to chromium ion ratios of 25 or greater were stable to alkaline-surfactant-polymer solutions if solution pH was 10.6 or less. When the polymer to chromium ion was 15 or less, chromium-polyacrylamide gels were stable to alkaline-surfactant-polymer solutions with pH values up to 12.9. Chromium-xanthan gum gels were stable to alkaline-surfactant-polymer solutions with pH values of 12.9 at the polymer to chromium ion ratios tested. Silicate-polyacrylamide, resorcinol-formaldehyde, and sulfomethylated resorcinol-formaldehyde gels were also stable to alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Iron-polyacrylamide gels were immediately destroyed when contacted with any of the alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Gel solutions under dynamic conditions of linear corefloods showed similar stability to alkaline-surfactant-polymer solutions as in

  5. Adaptation to flood risk: Results of international paired flood event studies

    DEFF Research Database (Denmark)

    Kreibich, Heidi; Di Baldassarre, Giuliano; Vorogushyn, Sergiy

    2017-01-01

    As flood impacts are increasing in large parts of the world, understanding the primary drivers of changes in risk is essential for effective adaptation. To gain more knowledge on the basis of empirical case studies, we analyze eight paired floods, that is, consecutive flood events that occurred...... in the same region, with the second flood causing significantly lower damage. These success stories of risk reduction were selected across different socioeconomic and hydro-climatic contexts. The potential of societies to adapt is uncovered by describing triggered societal changes, as well as formal measures...... and spontaneous processes that reduced flood risk. This novel approach has the potential to build the basis for an international data collection and analysis effort to better understand and attribute changes in risk due to hydrological extremes in the framework of the IAHSs Panta Rhei initiative. Across all case...

  6. On Flood Alert

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    lina braces fora particularly dangerous flood season in the wake of disastrous rainstorms Aseries of heavy storms since early May led to severe flooding and landslides in south and southwest China,causing heavy casualties and economic losses. Severe convective weather such as downpours,

  7. Discover Floods Educators Guide

    Science.gov (United States)

    Project WET Foundation, 2009

    2009-01-01

    Now available as a Download! This valuable resource helps educators teach students about both the risks and benefits of flooding through a series of engaging, hands-on activities. Acknowledging the different roles that floods play in both natural and urban communities, the book helps young people gain a global understanding of this common--and…

  8. Machine Learning Predictions of Flash Floods

    Science.gov (United States)

    Clark, R. A., III; Flamig, Z.; Gourley, J. J.; Hong, Y.

    2016-12-01

    This study concerns the development, assessment, and use of machine learning (ML) algorithms to automatically generate predictions of flash floods around the world from numerical weather prediction (NWP) output. Using an archive of NWP outputs from the Global Forecast System (GFS) model and a historical archive of reports of flash floods across the U.S. and Europe, we developed a set of ML models that output forecasts of the probability of a flash flood given a certain set of atmospheric conditions. Using these ML models, real-time global flash flood predictions from NWP data have been generated in research mode since February 2016. These ML models provide information about which atmospheric variables are most important in the flash flood prediction process. The raw ML predictions can be calibrated against historical events to generate reliable flash flood probabilities. The automatic system was tested in a research-to-operations testbed enviroment with National Weather Service forecasters. The ML models are quite successful at incorporating large amounts of information in a computationally-efficient manner and and result in reasonably skillful predictions. The system is largely successful at identifying flash floods resulting from synoptically-forced events, but struggles with isolated flash floods that arise as a result of weather systems largely unresolvable by the coarse resolution of a global NWP system. The results from this collection of studies suggest that automatic probabilistic predictions of flash floods are a plausible way forward in operational forecasting, but that future research could focus upon applying these methods to finer-scale NWP guidance, to NWP ensembles, and to forecast lead times beyond 24 hours.

  9. Deriving global flood hazard maps of fluvial floods through a physical model cascade

    Science.gov (United States)

    Pappenberger, Florian; Dutra, Emanuel; Wetterhall, Fredrik; Cloke, Hannah L.

    2013-04-01

    Global flood hazard maps can be used in the assessment of flood risk in a number of different applications, including (re)insurance and large scale flood preparedness. Such global hazard maps can be generated using large scale physically based models of rainfall-runoff and river routing, when used in conjunction with a number of post-processing methods. In this study, the European Centre for Medium Range Weather Forecasts (ECMWF) land surface model is coupled to ERA-Interim reanalysis meteorological forcing data, and resultant runoff is passed to a river routing algorithm which simulates floodplains and flood flow across the global land area. The global hazard map is based on a 30 yr (1979-2010) simulation period. A Gumbel distribution is fitted to the annual maxima flows to derive a number of flood return periods. The return periods are calculated initially for a 25 × 25 km grid, which is then reprojected onto a 1 × 1 km grid to derive maps of higher resolution and estimate flooded fractional area for the individual 25 × 25 km cells. Several global and regional maps of flood return periods ranging from 2 to 500 yr are presented. The results compare reasonably to a benchmark data set of global flood hazard. The developed methodology can be applied to other datasets on a global or regional scale.

  10. Deriving global flood hazard maps of fluvial floods through a physical model cascade

    Directory of Open Access Journals (Sweden)

    F. Pappenberger

    2012-11-01

    Full Text Available Global flood hazard maps can be used in the assessment of flood risk in a number of different applications, including (reinsurance and large scale flood preparedness. Such global hazard maps can be generated using large scale physically based models of rainfall-runoff and river routing, when used in conjunction with a number of post-processing methods. In this study, the European Centre for Medium Range Weather Forecasts (ECMWF land surface model is coupled to ERA-Interim reanalysis meteorological forcing data, and resultant runoff is passed to a river routing algorithm which simulates floodplains and flood flow across the global land area. The global hazard map is based on a 30 yr (1979–2010 simulation period. A Gumbel distribution is fitted to the annual maxima flows to derive a number of flood return periods. The return periods are calculated initially for a 25 × 25 km grid, which is then reprojected onto a 1 × 1 km grid to derive maps of higher resolution and estimate flooded fractional area for the individual 25 × 25 km cells. Several global and regional maps of flood return periods ranging from 2 to 500 yr are presented. The results compare reasonably to a benchmark data set of global flood hazard. The developed methodology can be applied to other datasets on a global or regional scale.

  11. Surfactant-free hydrothermal synthesis of lithium aluminate microbricks and nanorods from aluminium oxide nanoparticles.

    Science.gov (United States)

    Joshi, Upendra A; Chung, Soo Hyun; Lee, Jae Sung

    2005-09-21

    Beta-LiAlO2 microbricks and rectangular nanorods have been successfully synthesized from Al2O3 nanoparticles by a simple hydrothermal process without any surfactant or template, by simply changing the Li/Al molar ratio.

  12. Effect of Y2(CO3)3 and Surfactants on Electrorheological Performance of SiO2 Particle Materials

    Institute of Scientific and Technical Information of China (English)

    许明远; 马淑珍; 李淑新; 李俊然; 张少华; 魏宸官; 高松

    2004-01-01

    The SiO2 particle material has weak electrorheological (ER) activity. The ER performance of the SiO2 particles can be ameliorated after adsorbing Y2(CO3)3. In this paper, the effect of Y2(CO3)3 and different surfactants on the ER performance of the SiO2 particle materials is investigated. The results show that anionic or cationic surfactants maybe enhance the ER activity of SiO2 material, and nonionic surfactants cannot when surfactants are added during the process of the SiO2 particle preparation, only the anionic surfactant, AES, can enhance markedly the ER performance of the material. The surface area, pore volume and pore diameter of the particles were measured. The effect of Y2(CO3)3 and the surfactants on the microstructure of SiO2 materials and the relationship between ER effect and the microstructure are described.

  13. Cationic surfactants derived from lysine: effects of their structure and charge type on antimicrobial and hemolytic activities.

    Science.gov (United States)

    Colomer, A; Pinazo, A; Manresa, M A; Vinardell, M P; Mitjans, M; Infante, M R; Pérez, L

    2011-02-24

    Three different sets of cationic surfactants from lysine have been synthesized. The first group consists of three monocatenary surfactants with one lysine as the cationic polar head with one cationic charge. The second consists of three monocatenary surfactants with two amino acids as cationic polar head with two positive charges. Finally, four gemini surfactants were synthesized in which the spacer chain and the number and type of cationic charges have been regulated. The micellization process, antimicrobial activity, and hemolytic activity were evaluated. The critical micelle concentration was dependent only on the hydrophobic character of the molecules. Nevertheless, the antimicrobial and hemolytic activities were related to the structure of the compounds as well as the type of cationic charges. The most active surfactants against the bacteria were those with a cationic charge on the trimethylated amino group, whereas all of these surfactants showed low hemolytic character.

  14. Flood hazard and flood risk assessment using a time series of satellite images: a case study in Namibia.

    Science.gov (United States)

    Skakun, Sergii; Kussul, Nataliia; Shelestov, Andrii; Kussul, Olga

    2014-08-01

    In this article, the use of time series of satellite imagery to flood hazard mapping and flood risk assessment is presented. Flooded areas are extracted from satellite images for the flood-prone territory, and a maximum flood extent image for each flood event is produced. These maps are further fused to determine relative frequency of inundation (RFI). The study shows that RFI values and relative water depth exhibit the same probabilistic distribution, which is confirmed by Kolmogorov-Smirnov test. The produced RFI map can be used as a flood hazard map, especially in cases when flood modeling is complicated by lack of available data and high uncertainties. The derived RFI map is further used for flood risk assessment. Efficiency of the presented approach is demonstrated for the Katima Mulilo region (Namibia). A time series of Landsat-5/7 satellite images acquired from 1989 to 2012 is processed to derive RFI map using the presented approach. The following direct damage categories are considered in the study for flood risk assessment: dwelling units, roads, health facilities, and schools. The produced flood risk map shows that the risk is distributed uniformly all over the region. The cities and villages with the highest risk are identified. The proposed approach has minimum data requirements, and RFI maps can be generated rapidly to assist rescuers and decisionmakers in case of emergencies. On the other hand, limitations include: strong dependence on the available data sets, and limitations in simulations with extrapolated water depth values.

  15. Improving flood risk mapping in Italy: the FloodRisk open-source software

    Science.gov (United States)

    Albano, Raffaele; Mancusi, Leonardo; Craciun, Iulia; Sole, Aurelia; Ozunu, Alexandru

    2017-04-01

    management process, enhancing their awareness. This FOSS approach can promotes transparency and accountability through a process of "guided discovery". Moreover, the immediacy with which information is presented by the qualitative flood risk map, can facilitate and speed up the process of knowledge acquisition. An application of FloodRisk model is showed on a pilot case in "Serio" Valley, (North Italy), and its strengths and limits, in terms of additional efforts required in its application compared with EDQ procedure, have been highlighted focusing on the utility of the results provided for the development of FRMPs. Although they still present limits which prevent the FloodRisk application without critically consider the peculiarities of the investigated area in terms of available knowledge on hazard, exposure and vulnerability, the proposed approach surely produces an increase in available knowledge of flood risk and its drivers. This further information cannot be neglected for defining risk mitigation objectives and strategies. Hence, considering the ongoing efforts in the improvement of data availability and quality, FloodRisk could be a suitable tool for the next revision of flood risk maps due by December 2019, supporting effectively Italian and EU practitioners in the delineation of FRMPs (and for flood risk management in general).

  16. Aerobic biodegradation of amphoteric amine-oxide-based surfactants: Effect of molecular structure, initial surfactant concentration and pH.

    Science.gov (United States)

    Ríos, Francisco; Lechuga, Manuela; Fernández-Serrano, Mercedes; Fernández-Arteaga, Alejandro

    2017-03-01

    The present study was designed to provide information regarding the effect of the molecular structure of amphoteric amine-oxide-based surfactants and the initial surfactant concentration on their ultimate biodegradation. Moreover, given this parameter's pH-dependence, the effect of pH was also investigated. Three amine-oxide-based surfactants with structural differences in their hydrophobic alkyl chain were tested: Lauramine oxide (AO-R12), Myristamine oxide (AO-R14) and Cocamidopropylamine oxide (AO-Cocoamido). We studied the ultimate biodegradation using the Modified OECD Screening Test at initial surfactant concentrations ranged from 5 to 75 mg L(-1) and at pH levels from 5 to 7.4. The results demonstrate that at pH 7.4, amine-oxide-based surfactants are readily biodegradable. In this study, we concluded that ω-oxidation can be assumed to be the main biodegradation pathway of amine-oxides and that differences in the biodegradability between them can be explained by the presence of an amide group in the alkyl chain of AO-Cocoamido; the CN fission of the amide group slows down their mineralization process. In addition, the increase in the concentration of the surfactant from 5 to 75 mg L(-1) resulted in an increase in the final biodegradation of AO-R12 and AO-R14. However, in the case of AO-Cocoamido, a clear relationship between the concentration and biodegradation cannot be stated. Conversely, the biodegradability of AO-R12 and AO-R14 was considerably lower in an acid condition than at a pH of 7.4, whereas AO-Cocoamido reached similar percentages in acid conditions and at a neutral pH. However, microorganisms required more time to acclimate.

  17. A Methodology to Define Flood Resilience

    Science.gov (United States)

    Tourbier, J.

    2012-04-01

    Flood resilience has become an internationally used term with an ever-increasing number of entries on the Internet. The SMARTeST Project is looking at approaches to flood resilience through case studies at cities in various countries, including Washington D.C. in the United States. In light of U.S. experiences a methodology is being proposed by the author that is intended to meet ecologic, spatial, structural, social, disaster relief and flood risk aspects. It concludes that: "Flood resilience combines (1) spatial, (2) structural, (3) social, and (4) risk management levels of flood preparedness." Flood resilience should incorporate all four levels, but not necessarily with equal emphasis. Stakeholders can assign priorities within different flood resilience levels and the considerations they contain, dividing 100% emphasis into four levels. This evaluation would be applied to planned and completed projects, considering existing conditions, goals and concepts. We have long known that the "road to market" for the implementation of flood resilience is linked to capacity building of stakeholders. It is a multidisciplinary enterprise, involving the integration of all the above aspects into the decision-making process. Traditional flood management has largely been influenced by what in the UK has been called "Silo Thinking", involving constituent organizations that are responsible for different elements, and are interested only in their defined part of the system. This barrier to innovation also has been called the "entrapment effect". Flood resilience is being defined as (1) SPATIAL FLOOD RESILIENCE implying the management of land by floodplain zoning, urban greening and management to reduce storm runoff through depression storage and by practicing Sustainable Urban Drainage (SUD's), Best Management Practices (BMP's, or Low Impact Development (LID). Ecologic processes and cultural elements are included. (2) STRUCTURAL FLOOD RESILIENCE referring to permanent flood defense

  18. Parametric analysis of surfactant-aided imbibition in fractured carbonates.

    Science.gov (United States)

    Adibhatla, B; Mohanty, K K

    2008-01-15

    Many carbonate oil reservoirs are oil-wet and fractured; waterflood recovery is very low. Dilute surfactant solution injection into the fractures can improve oil production from the matrix by altering the wettability of the rock to a water-wetting state. A 2D, two-phase, multicomponent, finite-volume, fully-implicit numerical simulator calibrated with our laboratory results is used to assess the sensitivity of the process to wettability alteration, IFT reduction, oil viscosity, surfactant diffusivity, matrix block dimensions, and permeability heterogeneity. Capillarity drives the oil production at the early stage, but gravity is the major driving force afterwards. Surfactants which alter the wettability to a water-wet regime give higher recovery rates for higher IFT systems. Surfactants which cannot alter wettability give higher recovery for lower IFT systems. As the wettability alteration increases the rate of oil recovery increases. Recovery rate decreases with permeability significantly for a low tension system, but only mildly for high tension systems. Increasing the block dimensions and increasing oil viscosity decreases the rate of oil recovery and is in accordance with the scaling group for a gravity driven process. Heterogeneous layers in a porous medium can increase or decrease the rate of oil recovery depending on the permeability and the aspect ratio of the matrix block.

  19. 舰艇进水过程中的不沉性指标计算及实验研究%Research on ship unsinkability calculation model and experiment of flooding process

    Institute of Scientific and Technical Information of China (English)

    侯岳; 浦金云; 金涛

    2013-01-01

      为了描述舰艇进水过程中的不沉性指标随时间的变化关系,文章首先建立了进水过程的姿态参数时域微分模型;然后,分析了国外提出的流量差值迭代法的不足之处,建立了基于“四阶龙格-库塔”的数值求解算法,分析了其求解的物理意义,并进行了船模实验验证。最后,以某船模为对象进行了进水过程中浮性和稳性指标的仿真计算,计算结果揭示了进水过程可能会比进水稳定平衡状态更加危险的现象。%To describe the ship unsinkability index in the flooding process, the time domain differential e-quations of ship pose parameters are founded. The deficiency of the volumetric flow error iteration method is analyzed and the solution method based on four ranks Runge-Kutta is founded. Physical meaning of the arithmetic is analyzed too. Model experiments are made to validate the solution method then. Finally, the float and stability in flooding process of a given ship is calculated. The results indicate that the flooding process may be danger than the steady condition.

  20. Effect of Cross Linking Agent on Alkali/Surfactant/Polymer

    Institute of Scientific and Technical Information of China (English)

    ZHANG,Ke; LU,Xiang-Guo

    2008-01-01

    Alkali/surfactant/polymer (ASP) multisystem flooding technique, which has an expansive application prospect,is one of the enhancing oil recovery (EOR) methods. By adding the organic chromium to the ASP, the molecular structure of polymer was made to change, and the capability of controlling mobility coefficient of ASP was improved. The results showed that multisystem could still keep ultra-low interfacial tension between the multisystem and crude oil after addition of Cr3+. The resistance factor and residual resistance factor, the indicator which describes the capability of controlling mobility, upgraded strikingly. However its storage modulus and loss modulus,the indicator which describes viscoelasticity, increased. The results of physical simulation experiment indicated that this type of improved ASP could increase the recovery ratio by 4.3% compared to common ASP multisystem.

  1. Interfacial behaviour between oil/water systems using ionic surfactants from regional vegetable industry and animal pet

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Francisco Klebson G.; Alves, Juan V.A.; Dantas, Tereza N. Castro; Dutra Junior, Tarcilio V.; Barros Neto, Eduardo L. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2008-07-01

    Interfacial tension (IFT) is one of the most important physical properties in the study of fluid-fluid interfaces. In this research the surfactants - saponified coconut oil, saponified castor oil, saponified soybean oil, saponified sunflower oil and basis soap - were synthesized in laboratory, using carboxylic acids from regional industry and animal fat (bovine fat). This study focuses on the search of a high-efficient, low-cost, and safe for the environment flooding system to be applied in enhanced oil recovery. The principal aim of this work is the obtaining of interfacial tensions between oil/water systems, using the developed ionic surfactants. Results showed that the studied surfactants are able to reduce the IFT between oil and brine. The surfactant that was more effective in reducing the IFT value was the one from animal fat. The composition, as well as the kind of the bond, as saturated or unsaturated, of the surfactants has influence in the IFT value. The ionic surfactants from regional industry and animal fat besides presenting low cost propitiate very low interfacial tensions between oil and brine, favoring the interactions with residual oil and thus increasing oil recovery. (author)

  2. Surfactants in tribology, v.3

    CERN Document Server

    Biresaw, Girma

    2013-01-01

    The manufacture and use of almost every consumer and industrial product rely on application of advanced knowledge in surface science and tribology. These two disciplines are of critical importance in major economic sectors, such as mining, agriculture, manufacturing (including metals, plastics, wood, computers, MEMS, NEMS, appliances), construction, transportation, and medical instruments, transplants, and diagnostic devices. An up-to-date reference with contributions by experts in surface science and tribology, Surfactants in Tribology, Volume 3 discusses some of the underlying tribological a

  3. Anaerobic Biodegradation of Detergent Surfactants

    OpenAIRE

    Erich Jelen; Ute Merrettig-Bruns

    2009-01-01

    Detergent surfactantscan be found in wastewater in relevant concentrations. Most of them are known as ready degradable under aerobic conditions, as required by European legislation. Far fewer surfactants have been tested so far for biodegradability under anaerobic conditions. The natural environment is predominantly aerobic, but there are some environmental compartments such as river sediments, sub-surface soil layer and anaerobic sludge digesters of wastewater treatment plants which have str...

  4. Adsorption and desorption of cationic surfactants onto silica from toluene studied by ATR-FTIR.

    Science.gov