bluuebunny/crossref_metadata_2025_split huggingface dataset:
Integrated Acoustic, Mineralogy, and Geomechanics Characterization of the Huron Shale, Southern West Virginia, USA
Authors: Franquet J. A. , Mitra Arijit , Warrington D. S. , Moos Daniel , Lacazette Alfred 
Published: November 2011

Abstract
Exploitation of unconventional shale gas reservoirs depends on successful hydraulic fracturing and horizontal drilling. Mineralogy, organic matter content, acoustic anisotropy, and in-situ stress all play an important role for well completion design. As part of a comprehensive site study of the Upper Devonian Huron shale, borehole acoustic and mineralogy logging data, in addition to conventional logs, were acquired in a vertical well prior to hydraulic fracturing and microseismic monitoring of a series of laterals drilled from the same location. The acoustic data was processed for compressional wave, cross-dipole shear, Stoneley-derived horizontal shear, radial velocity variations, and borehole Stoneley reflectivity indicators. The cross-dipole anisotropy and the near-well radial slowness variations provided information about intrinsic anisotropy and stress sensitivity to determine the source of dipole-mode anisotropy. Significant transverse acoustic anisotropy was detected and used to obtain vertical and horizontal dynamic elastic properties. The mineralogy and petrophysical analysis were used to generate a micromechanical constitutive model to reproduce numerically the laboratory stress-strain behavior of the rock, from which quasi-static mechanical properties were determined. These were calibrated against triaxial tests on core samples from an offset well, and the vertical and horizontal static elastic rock properties were used to estimate the vertical variation of the horizontal stress. The resulting stress profile, along with accurate mineralogy and petrophysical analysis, provides important information to select the best vertical locations of lateral wells and to identify natural fracture barriers.
Coupled Geomechanical Modeling for Underground Coal Gasification
Authors: Deng Hui , Chen Zhangxin , Li Daiming 
Published: November 2011

Abstract
Simulation of underground coal gasification (UCG) is an integrated approach involving a Thermo-Hydro-Chemical-Mechanical process (THCM). The key is to understand the surface subsidence in the UCG process associated with the cavity growth and roof rock collapse during the coal seam combustion. However, the interaction between the mass transports and thermal-mechanical induced cavity and spalling cannot be fully captured by a conventional flow simulator without coupling geomechanics.
The literature has documented numerous methods of modeling the coupled Thermal-Chemical-Geomechanical process for UCG. The objective of this paper is to summarize the current research status and future developments of coupled geomechanical modeling approach for the UCG process, followed by a case study. Geochemistry and chemical reactions are modeled in the thermal reservoir simulator with a well-defined Controlled Retraction Injection Point (CRIP) configuration. A modular coupling approach is utilized in which geomechanical module calculates the changing of the stress and strain due to the changing of pressure and temperature, updating the porosity and permeability simultaneously. Finally, surface subsidence is investigated and limitations are also identified for future development.
Geomechanical Simulation of Caprock Performance for a Proposed, Low Pressure, Steam-Assisted Gravity Drainage Pilot Project
Authors: Uwiera-Gartner M. M. , Carlson M. R. , Walters D. , Palmgren C. T. 
Published: November 2011

Abstract
For oil sands assets having bitumen resources located near the ground surface, geomechanical assessments of caprock performance during steam-assisted gravity drainage (SAGD) operations have become increasingly important. These assessments need to determine and demonstrate whether the caprock can effectively withstand the induced stress and strain loadings from the SAGD operation throughout the life of the development.
The importance of caprock integrity for SAGD developments was realized following the loss of caprock containment at the Total E&P Canada Ltd., Joslyn Creek SAGD project in 2006. In light of this failure, the Alberta Energy Resources Conservation Board (ERCB) stipulated a series of response activities to address caprock integrity, including the requirement that pilot and commercial SAGD projects in Alberta need to conduct a geomechanical assessment of caprock integrity as part of the application process.
The authors completed a geomechanical simulation study of the Clearwater Formation caprock performance at a proposed, shallow, low pressure, SAGD (LP-SAGD) pilot project located southeast of Fort McMurray, Alberta, Canada. For this investigation, a 3D, coupled, reservoir and geomechanical simulation was conducted forecasting 10 years of asset response to the maximum operating pressure of 1,000 kPaa. The geomechanical response of the caprock to temperature changes, increased pore pressure and the induced stress and strain fields from the steam chamber was simulated as part of the caprock integrity assessment for the pilot project.
This paper presents the results of this simulation study and the uncertainties and risks associated with evaluating caprock containment of SAGD operations using numerical methods. The results of key geomechanical parameters, such as minimum principal effective stress, shear stress level, factor of safety and surface displacement are presented. A summary of the post-failure analyses of caprock containment at the Joslyn Creek SAGD project is presented.
Upscaling THAI: Experiment to Pilot
Authors: Greaves M. , Dong L. L. , Rigby S. P. 
Published: November 2011

Abstract
Numerical simulation of the insitu combustion process is complicated by sharp gradients, with different temporal and special regimes applying to the reaction front and diffusional transport. It is not possible to achieve fine scale solutions at field scale in a reasonable time, owing to the onerous computer requirements. Instead, grid coarsening procedures were used. Simulation solutions were obtained for a homogeneous reservoir section of the THAI® field pilot, near Conklin, Alberta, Canada. The reservoir model did not include an interbedded shale layer, or bottom water layer, and the study therefore represents a non-optimal, first stage simulation of the THAI process, prior to incorporating more reservoir complexities. The results show that the process is inherently stable over a six year operating period, since there was no oxygen in the produced gas. High temperatures are generated in the narrow combustion front zone (900 °C) but 60 m ahead the temperature is 500 – 600 °C. Rapid desaturation of reservoir water takes place ahead of the combustion front, allowing combustion gases to enter into the colder bitumen layers, thereby creating some oil mobility. Of particular significance, is the existence of a narrow, high saturation, Steam Zone, extending to more than 15 m, and up to 30 m during later stages of production. The steam zone propagates at up three times faster than that of the combustion front. Also, the Mobile Oil Zone (MOZ) is very significant characteristic of the THAI process throughout the whole production period. However, the temperature in the MOZ, close to the horizontal producer well, is quite low, around 150–180 °C. The oil recovery factor was approximately 60 % in the zone swept by the gas-steam front. Oil production peaked at 69 m3/day rate, averaging 350 barrrels per day for the single well pair.
Completion Evaluation of the Eagle Ford Formation with Heterogeneous Proppant Placement
Authors: Viswanathan A. , Altman R. , Oussoltsev D. , Kanneganti K. , Xu J. , Grant D. , Indriati S. , Peña A. , Loayza M. , Kirkham B. , Rhein T. 
Published: November 2011

Abstract
Since the initial success of multi-stage fracturing in horizontal laterals in the Eagle Ford Shale, multiple completion techniques have been implemented to optimize productivity. This paper discusses completion practices being followed in the Hawkville field, encompassing La Salle and McMullen counties in south Texas. While slickwater treatments provided the initial successes in the dry gas areas of the Eagle Ford, hybrid and channel fracturing treatments quickly showed improved, if not at least equal success in the wet gas areas while utilizing significantly less fluid and proppant volumes. The challenge has been to determine an optimum balance between the various completions parameters to increase production with less cost.
Optimization of Eagle Ford stimulation techniques became the most important objectives for completion and production engineers over the last two years, since the first horizontal multi-stage well was completed in the Hawkville field. Fracturing fluid systems, treatment rates, proppant types and concentrations along with completion details such as number of clusters, number of stages, and perforation intervals in horizontal laterals created a large number of variables impacting production for any operator. Implementation of any technology requires proper evaluation metrics that minimize geology, petrophysical and completion uncertainties. This paper describes the evaluation process of a novel stimulation technology – channel fracturing based on a heterogeneous proppant placement technique, and its comparison to existing conventional slickwater and hybrid stimulation treatments. The focus will be on the evaluation of in-situ conditions, challenges and production evaluation of different completion techniques using the following methodologies: normalized production comparison, productivity index analysis, neural network trained self-organizing maps and numerical simulations.
The initial production (IP) of the wells completed with the channel fracturing technique was 32–37% better, compared to offset conventional slickwater and hybrid wells. A detailed evaluation of horizontal well performance is described in this paper, based on statistical approaches and reservoir modeling. The combination of two evaluation techniques substantiates the statement that the incorporation of the channel fracturing technology as part of the completion design had a positive impact for the stimulation of wells in the Eagle Ford formation.
Reactive Thermal Reservoir Simulation: Hydrogen Sulphide Production in SAGD
Authors: Kapadia Punitkumar R. , Wang Jacky , Kallos Michael S. , Gates Ian D. 
Published: November 2011

Abstract
In SAGD, steam is injected into a bitumen bearing oil sands formation. Steam temperature ranges from about 200 to 260°C and at these temperatures, bitumen undergoes aquathermolysis yielding acid gases such as hydrogen sulphide and carbon dioxide. SAGD simulation models in the literature often account for spatial heterogeneity of the geology and oil composition and heat transfer, multiphase flow, gas solubility effects, and viscosity variations with temperature, however, none account for the chemistry of SAGD. Here, we consider aquathermolysis reactions to understand the reactive zones in the SAGD process and how the process generates acid gases via aquathermolysis. The results show that SAGD is both a physical and chemical-reactive process.
Improving Retention for Principles of Accounting Students: Ultra-Short Online Tutorials for Motivating Effort and Improving Performance
Authors: Sargent Carol Springer , Borthick A. Faye , Lederberg Amy R. 
Published: November 2011

ABSTRACT
As student learning outcomes and retention receive more attention in higher education, failure rates in principles of accounting courses, gate-keeper courses for business majors, are coming under scrutiny. This study shows promising results from use of a learning innovation, ultra-short online videos, for addressing three common reasons for poor performance: intimidating class environments, low aptitude, and low motivation. For students at all achievement levels, tutorial use rates were above 60 percent, even though there was no course credit for viewing them. Students using the tutorials had significantly lower course drop rates and better pass rates. Tutorial use was correlated with higher exam scores, although the effect was moderate. Based on analysis of the two-year periods before and after implementation, the use of tutorials was correlated with higher course grades. Tutorial use remained at high levels two years after implementation even without instructors encouraging students to use them.
Evaluation of dexmedetomidine and ketamine in combination with various opioids as injectable anesthetic combinations for castration in cats
Authors: Ko Jeff C. , Austin Brenda R. , Barletta Michele , Weil Ann B. , Krimins Rebecca A. , Payton Mark E. 
Published: November 2011

Abstract
Objective—To compare the efficacy and cardiorespiratory effects of dexmedetomidine-ketamine in combination with butorphanol, hydromorphone, or buprenorphine with or without reversal by atipamezole in cats undergoing castration.
Design—Prospective, randomized, split-plot, blinded study.
Animals—30 healthy male cats.
Procedures—Cats were assigned to receive dexmedetomidine (25 μg/kg [11.4 μg/lb]) and ketamine (3 mg/kg [1.4 mg/lb]) with butorphanol (0.2 mg/kg [0.09 mg/lb]; DKBut; n = 10), hydromorphone (0.05 mg/kg [0.023 mg/lb]; DKH; 10), or buprenorphine (30 μg/kg [13.6 μg/lb]; DKBup; 10). Drugs were administered as a single IM injection. Supplemental isoflurane was administered to cats if the level of anesthesia was inadequate for surgery. At the conclusion of surgery, half the cats (5 cats in each treatment group) received atipamezole (250 μg/kg [113.6 μg/lb], IM) and the remainder received saline (0.9% NaCl) solution IM. All cats received meloxicam (0.2 mg/kg, SC) immediately prior to the conclusion of surgery.
Results—All drug combinations induced lateral recumbency, and intubation was achievable in 13 of 30 (43%) cats at 10 minutes after injection. Supplemental isoflurane was needed for the surgery in 1 of 10 of the DKBut-, 2 of 10 of the DKH-, and 7 of 10 of the DKBup-treated cats. Cats that received atipamezole had a significantly shorter recovery time.
Conclusions and Clinical Relevance—DKBut and DKH combinations were suitable injectable anesthetic protocols for castration in cats commencing at 10 minutes after injection, but cats receiving DKBup may require additional time or anesthetics for adequate anesthesia.
Opposing flows in a one dimensional convection-diffusion problem
Authors: O’Riordan Eugene 
Published: November 2011

Abstract
In this paper, we examine a particular class of singularly perturbed convection-diffusion problems with a discontinuous coefficient of the convective term. The presence of a discontinuous convective coefficient generates a solution which mimics flow moving in opposing directions either side of some flow source. A particular transmission condition is imposed to ensure that the differential operator is stable. A piecewise-uniform Shishkin mesh is combined with a monotone finite difference operator to construct a parameter-uniform numerical method for this class of singularly perturbed problems.
Mesurer la pauvreté multidimensionnelle : les limites
Authors: Alkire Sabina 
Published: November 2011

Résumé Jamais auparavant, nous n’avions disposé d’autant de données sur les aspects non monétaires de la pauvreté. Parallèlement, les méthodes de mesure multidimensionnelles ont fait d’immenses progrès depuis quinze ans, ouvrant de nouvelles perspectives pour mesurer la pauvreté multidimensionnelle à l’échelle locale, nationale et internationale. Pourtant, le fait que l’on puisse construire une mesure de la pauvreté multidimensionnelle ne signifie pas que cette mesure apportera nécessairement une valeur ajoutée. Le recours à des dimensions multiples n’oblige cependant pas à avoir un indice de la pauvreté multidimensionnelle. Nous tenterons d’analyser dans cet article, quand, comment et pourquoi certaines mesures de la pauvreté multidimensionnelle peuvent présenter un intérêt supplémentaire, en posant les limites de leur contribution, et en introduisant un ensemble de problématiques en suspens. La valeur ajoutée essentielle que peut rigoureusement apporter un indice de pauvreté multidimensionnelle est qu’il véhicule de nouvelles informations, qui ne sont pas captées par une quelconque mesure unidimensionnelle sur la distribution commune des désavantages et la composition de la pauvreté chez les populations « poly-désavantagées » (multiply deprived). Il fournit également une description cohérente de l’évolution globale de la pauvreté multidimensionnelle dans le temps et dans l’espace. Pour explorer ces questions, nous présentons une approche générale de la mesure de la pauvreté multidimensionnelle – celle qui reflète une distribution commune. Nous présentons ensuite une classe de mesures de la pauvreté au sein de cette approche. Nous présentons également une application récente de l’une des mesures au sein de cette famille : le nouvel Indice de Pauvreté Multidimensionnelle lancé en 2010 pour 104 pays. Pointer du doigt la valeur ajoutée des indices de pauvreté multidimensionnelle ne revient pas à dire qu’il faut abandonner les mesures unidimensionnelles, mais plutôt qu’il faut les compléter. Investir davantage dans les mesures de la pauvreté multidimensionnelle peut contribuer à faire mieux comprendre ce phénomène et permettre de créer des instruments de politique économique utiles.
La croissance du PIB rendra-t-elle les habitants des pays en développement plus heureux ?
Authors: Clark Andrew E. , Senik Claudia 
Published: November 2011

Résumé Ce texte s’interroge sur ce que les pays à bas revenu peuvent attendre de la croissance en termes de bien-être. Interprétant les données internationales disponibles, il observe que, conformément au paradoxe d’Easterlin, au sein d’un pays, les individus les plus riches se déclarent plus heureux ; les habitants des pays riches se déclarent plus heureux que ceux des pays pauvres ; mais sur le long terme, le bien-être moyen d’un pays ne semble pas s’élever avec le revenu national. En réalité, le lien dynamique entre croissance et bonheur reste vivement débattu ; la question est de savoir si le coefficient de corrélation entre les deux grandeurs peut être considéré comme négligeable (« too small to matter ») . Les explications de la faible corrélation entre croissance du revenu et bien-être subjectif au cours du temps tiennent à la nature même de la croissance (par exemple les effets secondaires négatifs tels que la pollution) et à l’importance de phénomènes psychologiques tels que les comparaisons et l’adaptation. À cet égard, les données disponibles renferment deux enseignements importants : les comparaisons de revenu semblent bien affecter le bien-être subjectif, même dans les pays très pauvres ; cependant, l’adaptation est sans doute un phénomène plus spécifique aux pays riches. Nous pensons que les données disponibles ne permettent pas d’écarter l’idée que la croissance élèvera le bonheur dans les pays à faible revenu. D’une part, les analyses longitudinales internationales (qui conduisent à rejeter cette corrélation) reposent sur des mesures agrégées, qui sont moins fiables que les mesures individuelles (qui conduisent à valider cette corrélation). D’autre part, le développement est un processus qualitatif qui implique des décollages et des seuils. Or, les données révèlent que ces changements de régime s’accompagnent d’une évolution parallèle des mesures de satisfaction subjectives. Le cas des pays en transition est particulièrement remarquable à cet égard : les scores moyens de satisfaction dans la vie suivent étroitement l’évolution du PIB pendant les dix premières années environ du processus de transition, jusqu’à ce que le régime se stabilise. Si des mesures subjectives de bien-être étaient disponibles dans les pays à bas revenu, elles aideraient certainement à mesurer et suivre les différents stades et dimensions du processus de développement.
Photostimulated Au Nanoheaters in Polymer and Biological Media: Characterization of Mechanical Destruction and Boiling
Authors: Hühn Dominik , Govorov Alexander , Gil Pilar Rivera , Parak Wolfgang J. 
Published: November 2011

AbstractAgglomerated gold nanoparticle clusters embedded in polyelectrolyte films are optically excited, which results in local ablation of material from the polyelectrolyte films and in some cases leads to the formation of a gas bubble. Evidence is given that this process is mediated by superheating of the medium around the excited gold nanoparticle clusters. This process is highly dependent on the medium used. Besides the boiling point, salt and proteins in the medium also affect the formation of gas bubbles. These data demonstrate that the type of medium must be considered when describing light‐mediated heating of gold nanoparticle clusters, which are fixed in a matrix surrounded by medium.
Exploring How to Increase the Brightness of Surface‐Enhanced Raman Spectroscopy Nanolabels: The Effect of the Raman‐Active Molecules and of the Label Size
Authors: Amendola Vincenzo , Meneghetti Moreno 
Published: November 2011

AbstractDue to the surface‐enhanced Raman scattering (SERS) effect, SERS labels based on noble‐metal nanoparticles loaded with Raman‐active molecules are good candidates for ultrasensitive multiplexed assays and in vitro/in vivo imaging. However, understanding how to maximize the brightness of such labels is of paramount importance for their widespread application. The effective differential Raman scattering cross‐section (dσR/dΩ) of SERS labels made of pegylated gold nanoparticles loaded with various Raman active molecules (Raman reporters) is studied. It is found that proper choice of the Raman reporter and of nanoparticle size can enhance the dσR/dΩ by several orders of magnitude. The experimental results are understood by considering the molecular cross‐section for resonant Raman scattering and the local electromagnetic enhancement factor (GSERS) in the nearby of gold nanoparticles. These results are useful to guide the design of SERS labels with improved performances and to provide a reference for the comparison of the absolute value of the dσR/dΩ of SERS labels based on metal nanoparticles.
Facile Preparation of 2‐Substituted Benzoxazoles and Benzothiazoles via Aerobic Oxidation of Phenolic and Thiophenolic Imines Catalyzed by Polymer‐Incarcerated Platinum Nanoclusters
Authors: Yoo Woo‐Jin , Yuan Hao , Miyamura Hiroyuki , Kobayashi Shū 
Published: November 2011

AbstractPlatinum nanoclusters supported on a polymer/carbon black composite material was found to be an excellent catalyst for the oxidative cyclization of phenolic and thiophenolic Schiff bases to 2‐substituted benzoxazoles and benzothiazoles under ambient conditions.
Cinchona Alkaloid‐Catalyzed Enantioselective Amination of α,β‐Unsaturated Ketones: An Asymmetric Approach to Δ2‐Pyrazolines
Authors: Campbell Nathaniel R. , Sun Bingfeng , Singh Ravi P. , Deng Li 
Published: November 2011

AbstractΔ2‐Pyrazolines are of significant medicinal and synthetic interest due to their therapeutic properties and utility in the synthesis of 1,3‐diamines, yet few asymmetric methods exist to prepare them. An unprecedented and highly enantioselective organocatalytic synthesis of 2‐pyrazolines was achieved through an asymmetric conjugate addition catalyzed by 9‐epi‐amino Cinchona alkaloids followed by deprotection‐cyclization, which furnished chiral 2‐pyrazolines in 46–78% yield and 59–91% ee. This bifunctional catalytic methodology thus provides easy access to a considerable range of optically active 3,5‐dialkyl 2‐pyrazolines.