bluuebunny/crossref_metadata_2025_split huggingface dataset:
Technology for Confecting Polymer Solution With Desalinated Produced Water
Authors: Liu Shumeng , Dong Xigui , Ban Hui , Wang Tao , Pan Wenlong , Yu Haijun , Guo Cuiling , Suo Chunlei 
Published: March 2009

Summary
Polymer-flooding technology has been used widely in the Daqing oil field of China in recent years. To maintain the viscosity of a polymer solution, fresh water typically is used to confect the polymer solution instead of produced water. In doing so, a problem emerges—the produced water cannot be injected completely into the stratum. The superfluous produced water has to be treated to meet the requirements of discharge, which increases the cost of oil production. In this study, the produced water is desalinated through the implentation of of an electrodialysis principle. A set of experimental equipment that can desalinate produced water at a capacity of 300 m3/d was established at a produced-water-treat-ment station in the Daqing oil field. The experiment's results indicate that the total salinity of desalinated produced water can be less than 1000 mg/L. The polymer solution confected with desalinated produced water has more statistically significant characteristics than fresh water in that the viscosity increases by 63.5% and the recovery rate increases by 4.5%. This experimental study will be beneficial to keeping the balance of oily-water production and injection in oil fields. This technology for pro-duced-water desalination will have better application prospects in the polymer-flooding process.
A Methodology To Reduce Uncertainty Constrained to Observed Data
Authors: Maschio Célio , Schiozer Denis J. , Filho Marcos A. B. Moura , Becerra Gustavo G. 
Published: March 2009

Summary
This paper presents a new method to deal with uncertainty mitigation by using observed data, integrating the uncertainty analysis and the history-matching processes. The proposed methods are robust and easy to use, and offer an alternative to traditional history-matching methods. The main characteristic of the method is the use of observed data as constraints to reduce the uncertainty of the reservoir parameters. The main objective is the integration of uncertainty analysis with history matching, providing a natural manner to make predictions under reduced uncertainty. Three methods are proposed: (1) probability redistribution, (2) elimination of attribute levels, and (3) redefinition of attribute values. To test the results of the proposed approach, we investigated three reservoir examples. The first one is a synthetic and simple case; the second one is a synthetic but realistic case; and the third one is a real reservoir from the Campos basin of Brazil. The results presented in the paper show that it is possible to conduct an integrated study of uncertainty analysis and history matching. The main contribution of this work is to present a practical way to increase the reliability of prediction through reservoir-simulation models that incorporate uncertainty analysis in the history period and provide reliable reservoir-simulation models for prediction forecast.
Seawater in Chalk: An EOR and Compaction Fluid
Authors: Austad Tor , Strand Skule , Madland Merete V. , Puntervold Tina , Korsnes Reidar I. 
Published: March 2009

Summary
North Sea chalk reservoirs are characterized as being purely biogenic and naturally fractured, having low matrix permeability and very high porosity (30 to 45%). The reservoir temperature is usually high, more than 90°C, and the wetting conditions appear to be moderately water-wet to neutral. Even though the permeability contrast between the matrix and fractures is significant, the injection of seawater has been a great success with the Ekofisk field as an example (estimated oil recovery is now approaching 50%). Seawater improves the water wetness of chalk, which increases the oil recovery by spontaneous imbibition and viscous displacement.
During the primary production phase by pressure depletion, extensive compaction was observed and, at that time, it was regarded as an important drive mechanism for oil recovery. The compaction continued in the waterflooded areas even though the reservoir was repressurized by the injected seawater. The phenomenon has been described as water weakening of chalk, and production costs have increased because of the loss of wells and substitution of platforms.
This paper gives an overview of the chemical aspects of the interaction between seawater and the chalk. Surface active components in seawater, such as Ca2+, Mg2+, and SO42-, will play an important role in both wettability modification and rock mechanics. In that sense, injection of seawater into chalk must be regarded as a tertiary-oil-recovery technique. Chemical models describing the wettabilty alteration and enhanced water weakening of chalk by seawater are suggested and presented.
Effects of Steam on Heavy Oil Combustion
Authors: Lapene A. , Castanier L. M. , Debenest G. , Quintard M. , Kamp A. M. , Corre B. 
Published: March 2009

In-Situ Combustion
In-situ combustion (ISC) is an enhanced oil-recovery method. Enhanced oil recovery is broadly described as a group of techniques used to extract crude oil from the subsurface by the injection of substances not originally present in the reservoir with or without the introduction of extraneous energy (Lake 1996). During ISC, a combustion front is propagated through the reservoir by injected air. The heat generated results in higher temperatures leading to a reduction in oil viscosity and an increase of oil mobility. There are two types of ISC processes, dry and wet combustion.
In the dry-combustion process, a large part of the heat generated is left unused downstream of the combustion front in the burned-out region. During the wet-injection process, water is co-injected with the air to recover some of the heat remaining behind the combustion zone. ISC is a very complex process. From a physical point of view, it is a problem coupling transport in porous media, chemistry, and thermodynamics. It has been studied for several decades, and the technique has been applied in the field since the 1950s. The complexity was not well understood earlier by ISC operators. This resulted in a high rate of project failures in the 1960s, and contributed to the misconception that ISC is a problem-prone process with low probability of success. However, ISC is an attractive oil-recovery process and capable of recovering a high percentage of oil-in-place, if the process is designed correctly and implemented in the right type of reservoir (Sarathi 1999).
This paper investigates the effect of water on the reaction kinetics of a heavy oil by way of ramped temperature oxidation under various conditions.
Application of Artificial Neural Networks to Downhole Fluid Analysis
Authors: Hegeman Peter , Dong Chengli , Varotsis Nikos , Gaganis Vassilis 
Published: March 2009

Summary
Reservoir characterization and asset management require comprehensive information about formation fluids. Obtaining this information at all stages of the exploration and development cycle is essential for field planning and operation. Traditionally, fluid information has been obtained by capturing samples and then measuring the pressure/volume/temperature (PVT) properties in a laboratory. More recently, downhole fluid analysis (DFA) during formation testing has provided real-time fluid information. However, the extreme conditions of the downhole environment limit the DFA-tool measurements to only a small subset of the fluid properties provided by a laboratory. Nevertheless, these tools are valuable in predicting other PVT properties from the measured data. These predictions can be used in real time to optimize the sampling program, to help evaluate completion decisions, and to understand flow-assurance issues.
The petroleum industry has devoted much effort to developing computational methods to model phase behavior. Two approaches are prevalent—simple correlations and equation-of-state (EOS) models. However, in recent years, artificial-neural-network (ANN) technology has been applied successfully to many petroleum-engineering problems, including the prediction of PVT behavior. ANN technology can recognize patterns in data, adjust dynamically to changes, infer general rules from specific cases, and accept a large number of input variables. An ANN architecture can allow for continuous improvement by expanding the training database with new data.
In this paper, we present the application of ANN technology to DFA. We demonstrate this with an ANN model that uses the DFA-tool measurements of fluid composition as input and produces predictions of gas/oil ratio (GOR), a key PVT property used in real time to monitor a formation-tester sampling job. The ANN also provides an uncertainty estimation of its outputs as a quality-assurance indicator. We compare ANN results with those from the algorithms used by DFA tools.
Improved Fluid Characterization for Miscible Gas Floods
Authors: Egwuenu A. M. , Johns R. T. , Li Y. 
Published: March 2009

Summary
Equations of state (EOSs) are typically tuned to black-oil pressure/volume/temperature (PVT) data such as constant volume-depletion, constant-composition-expansion, differential-liberation, and separator tests. Other PVT data more appropriate for gas injection could include multicontact and swelling tests and slimtube tests. The standard method of tuning, however, does not typically incorporate important displacement parameters, such as the minimum miscibility pressure (MMP), minimum miscibility enrichment (MME), or the likely compositions that result in a reservoir from condensing-vaporizing (CV) displacements.
This paper demonstrates an improved reservoir-fluid-characterization procedure for miscible gas floods that can represent the interaction of flow and phase behavior more accurately. We demonstrate the approach for two displacements, an 11-component CO2 flood and a 12-component enriched-gas flood. The method-of-characteristic (MOC) theory is used to determine the MME (or MMP) of both lumped and unlumped models. The results show that by tuning to the calculated MME/MMP, fewer pseudocomponents are required to characterize the fluid than with conventional tuning methods. For the cases studied, fluids lumped to as few as four or five pseudocomponents can provide a good match to the composition profiles and oil recoveries of the unlumped models.
Wettability Alteration in Gas-Condensate Reservoirs To Mitigate Well Deliverability Loss by Water Blocking
Authors: Noh Myeong , Firoozabadi Abbas 
Published: March 2009

Summary
Liquid blocking in some gas-condensate reservoirs is a serious problem when the permeability is low (for example, of the order of 10 md or less). The current practice centers mainly on hydraulic fracturing to improve gas flow. In most cases, the frequency of application results in high costs. An alternative is the permanent alteration of wettability from liquid-wetting to preferentially gaswetting. In this work, we present an experimental study of wettability alteration to preferential gas-wetting using a multifunctional surfactant and polymer synthesized for this particular application. The treatments are performed with an alcohol-based-surfactant/ polymer solution. We treat Berea cores and reservoir-rock samples from two gas-condensate reservoirs. In one of the reservoirs, water blocking has resulted in a significant reduction of well deliverabil-ity. The treatment provides significant improvement on the phase mobility. In this study, our focus is the investigation of water/gas two-phase flow at high temperatures (80 and 140°C).
Basic measurements such as contact angle, spontaneous imbibition, and the effect on the absolute permeability are discussed. The initial liquid saturation at the time of treatment may have an influence on the wettability alteration. The results of the treatment on oil-saturated and water-saturated cores are presented. The treatment by alcohol without using the polymer is compared and discussed. Two-phase-flow tests in single-phase and two-phase injections are performed before and after the treatment using brine and gas. Relative permeabilities of gas and water are measured, and the improvement after the treatment is presented. Various measurements in our work show that water and gas relative permeability increase significantly in a wide range, especially at high liquid saturation.
Environmental Products Manufacturing: A Look inside the Green Industry
Authors: Becker Randy A , Shadbegian Ronald J 
Published: March 2009

Abstract
The green industry is often noted in discussions of the costs and benefits of environmental policy, and it has been characterized as a unique industry with substantial potential for employment growth, well-paying green jobs, and export opportunities. In this paper, we examine the characteristics and recent economic performance of the green industry, using establishment-level data on environmental products manufacturers (EPMs) from the 1995 Survey of Environmental Products and Services, together with data from the Annual Survey of Manufactures and the Census of Manufactures. Results suggest that there are some differences between EPMs and their non-EPM counterparts in the same industry, in terms of employment, employee compensation, exports, and productivity. However, we do not find any evidence that EPMs performed any better than otherwise similar plants, in terms of survival, employment growth, wage growth, and export growth. We suggest that the green industry (as defined here) may not be as exceptional as is sometimes maintained.
In Vivo Evaluation of DIAGNOdent for the Quantification of Occlusal Dental Caries
Authors: Khalife M. A. , Boynton J. R. , Dennison J. B. , Yaman P. , Hamilton J. C. 
Published: March 2009

Clinical RelevanceThere is a weak correlation between DIAGNOdent readings and carious lesion depth and volume. Based on the current study, the appropriate DIAGNOdent cut-off point to detect carious lesions reaching the DEJ or beyond is between 35 and 40.
Effect of Fiber Nets, Application Techniques and Flowable Composites on Microleakage and the Effect of Fiber Nets on Polymerization Shrinkage in Class II MOD Cavities
Authors: Ozel E. , Soyman M. 
Published: March 2009

Clinical Relevance
Fiber nets applied to Class II composite restorations resulted in a significant reduction in microleakage. Fiber nets also decreased polymerization shrinkage. Therefore, these materials may be acceptable for clinical applications. Incremental placement remains the preferred restorative technique for posterior composite restorations.
Durability of Enamel Bonding Using One-step Self-etch Systems on Ground and Unground Enamel
Authors: Reis A. , Moura S. K. , Pellizzaro A. , Dal-Bianco K. , Andrade A. M. , Grande R. H. M. , Loguercio A. D. 
Published: March 2009

Clinical Relevance
The improvement of resin-enamel bond strengths after using Si-C paper and diamond burs for enamel preparation is material dependent. No degradation of enamel bond strength could be observed for any one-step self-etch adhesive system after 12 months of water storage.
Effect of Acid Neutralization and Mechanical Cycling on the Microtensile Bond Strength of Glass-ceramic Inlays
Authors: Saavedra G. , Ariki E. K. , Federico C. D. , Galhano G. , Zamboni S. , Baldissara P. , Bottino M. A. , Valandro L. F. 
Published: March 2009

Clinical Relevance
Acid neutralization of the ceramic surface etched with hydrofluoric acid appears to be unnecessary.
Effect of Enamel Etching Time on Roughness and Bond Strength
Authors: Barkmeier W. W. , Erickson R. L. , Kimmes N. S. , Latta M. A. , Wilwerding T. M. 
Published: March 2009

Clinical Relevance
Traditionally, etch-and-rinse adhesive systems have used phosphoric acid to condition enamel surfaces and successfully create a strong, durable bond to resin-based materials. Newer adhesive systems now use acid monomers to bond resin materials to both enamel and dentin. These newer adhesives do not provide the same degree of bonding to enamel as etch-and-rinse systems, and extending the application time does not improve their performance.
Influence of Post and Resin Cement on Stress Distribution of Maxillary Central Incisors Restored with Direct Resin Composite
Authors: Spazzin A. O. , Galafassi D. , de Meira-Júnior A. D. , Braz R. , Garbin C. A. 
Published: March 2009

Clinical Relevance
According to finite element analysis, the zirconia ceramic post created higher stress levels in the post and slightly less in dentin compared with glass fiber posts. Resin cement with a high elastic modulus created higher stress levels in the cement layer. The different film thicknesses of cement did not create significant changes in stress levels.
Vehicle Suspension Measurements: Evaluation of the Benefits of Dynamic over Quasistatic Kinematics and Compliance Testing
Authors: Wei T. E. , Dorfi H. R. 
Published: March 2009

Abstract
Vehicle dynamics packages can be used to simulate handling or braking maneuvers that would otherwise need to be performed outdoors. Many of the parameters for these types of vehicle models are determined through kinematics and compliance (K&C) measurements. Machines that perform these measurements apply various forces or moments and measure the response of the vehicle. The rate that these forces or moments are applied can be quasistatic or dynamic. Machines that are capable of performing dynamic tests are more expensive due to the need for inertia compensation, sensors that can acquire data at higher rates, and larger actuators or hydraulic power supplies. However, it is possible that measurements of dynamic vehicle response may increase the fidelity of parameter identification, compared to the sole use of quasistatic tests. One reason that parameter identification may be more accurate is the rate of force and moment application in dynamic tests is more like those in the actual maneuvers that are desirable to simulate.
A study was performed to determine where the advantages of performing dynamic K&C testing lie. Quasistatic K&C tests, along with dynamic tests performed at several frequencies up to 3.0 Hz, were performed on the front axle of a front-wheel drive compact sedan, using an MTS Systems High-Rate K&C Machine. Assessment of any advantages of dynamic K&C testing has been made through correlations of the vehicle response between dynamic and quasistatic tests.
Examination of the Structure and Micro-Hardness of a Laser-Constituted Surface Layer Deposited on the Constructional Steel
Authors: Kłysz Sylwester , Bień Anna 
Published: March 2009

Examination of the Structure and Micro-Hardness of a Laser-Constituted Surface Layer Deposited on the Constructional SteelThe paper has been intended to present results of the micro- and macroscopic examination of the structure, as well as measurements of micro-hardness of surface layers of specimens made from the toughening (heat-treatable) constructional steel 50H subjected to laser hardening. Basing on X-ray examination with the DRON-4 and the Seifert XRD 3003 diffractometers, parameters of crystalline lattice and quantitative contents of particular phases have been found.
A Method to Estimate Operational Fatigue Life of Aeronautical Structural Components and Experimental Verification Thereof - An Outline
Authors: Tomaszek Henryk , Żurek Józef , Kłysz Sylwester 
Published: March 2009

A Method to Estimate Operational Fatigue Life of Aeronautical Structural Components and Experimental Verification Thereof - An OutlineThe study presents an attempt to estimate fatigue life of structural components with further verification of the applied method by means of testing the specimens taken. Therefore, it has been assumed that a specimen subjected to tests is a structural component of a real system, and operational loads have been simulated in the form of a predefined loading scheme. All parameters necessary for the method have been derived from the analyses of both the specimens subjected to tests and properties of the preset load spectrum.The applied method of fatigue life estimation represents a probabilistic approach based on the Paris formula for the crack growth rate, and on difference equations that after some transformation result in an equation of the Fokker-Planck type. A probability density function of a crack length is a solution to this equation and depends on either the total time of operating the component in question or the number of load cycles applied.The probability density function of a crack length has been used to find out a formula for the probability of not exceeding the permissible crack length against the number of load cycles. The derived relationship has been applied after normalization to estimate fatigue life as based on results of experimental examination of specimens made from titanium alloy.The nomenclature of the aeronautical engineering is used throughout the paper due to the assumption that the component exposed to tests represents a part of an aircraft. This, in turn, has been intended to show some specific application(s) of the formulated model.
Właściwości Dynamiczne Linii Hydraulicznych Lotniczych Napędów Hydraulicznych
Authors: Ułanowicz Leszek 
Published: March 2009

Właściwości Dynamiczne Linii Hydraulicznych Lotniczych Napędów HydraulicznychW artykule zaprezentowano wyniki analiz własności dynamicznych linii hydraulicznej uwzględniających efekt bezwładności cieczy płynącej w przewodzie sztywnym, jak i giętkim, efekt ściśliwości tej cieczy i efekt tarcia lepkiego. W rozważaniach potraktowano linię hydrauliczną jako czwórnik o dwóch wejściach i dwóch wyjściach, charakteryzujący się określoną macierzą transmitancji. Główne rozważania przeprowadzono dla modelu o zmiennej rezystancji. Podano rozwiązanie ogólne w funkcji operatora Laplace'a oraz adaptację modelu linii hydraulicznej dla przepływu turbulentnego i przepływu przez przewód o sprężystych ściankach. Wprowadzając odpowiednie uproszczenia do modelu o zmiennej rezystancji otrzymano kolejno model o stałej rezystancji i model linii bez strat.
Dynamic Properties of Hydraulic Lines for Fluid Power Transmission
Authors: Ułanowicz Leszek 
Published: March 2009

Dynamic Properties of Hydraulic Lines for Fluid Power TransmissionThis paper presents the results of a hydraulic line dynamic properties analysis taking into account inertia of the fluid flowing in rigid and flexible lines, the compressibility effect for this fluid and the viscous friction effect. The following are described and analyzed: solution of the wave equation in the form binding four variables: pressure and flow rate at the line input, and pressure and flow rate and the line output; two of the above-mentioned variables should be regarded as independent (input) and the other two as dependent (output), the accuracy comparison of distributed parameters model to lumped parameters model with regard to applicability range in hydraulic systems analysis, pressure value at given installation points as a response to rapid valve closing (transient response) or to valve opening (fluid hammer effect). In these considerations the hydraulic line is regarded as a two-port with two inputs and two outputs with a definite transmittance matrix. Main considerations concern the variable resistance model. A general solution is given as a function of the Laplace operator. Adaptation of the hydraulic line model to the turbulent flow and to the flow through a line with elastic boundaries is given. Introducing appropriate simplifications into the variable resistance model, the constant resistance model and lossless line model is obtained.Also, general solutions for three different lump parameter models are presented. Accuracy of individual methods are compared with examples for selected systems.