bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Trapping Capacity of Nanofluids on Migrating Fines in Sand
Authors: Ogolo Naomi Amoni 
Published: September 2013

Abstract
Fines Migration in reservoirs during hydrocarbon production has posed a big challenge to the oil and gas industry. Various methods have been tried but a lasting solution to the problem seems elusive. The application of nanotechnology to solve fines migration problem in reservoirs is still under investigation. This paper is focused on identifying the type of nanoparticles and dispersant that can effectively trap migrating fines in sand, thus prevent particle migration through the pore spaces of sand. Nine types of nanoparticles were experimented with using four kinds of fluid in the absence and in the presence of crude oil. The amount of fines that 3g/l of each nanofluid can trap before breakthrough of fines occurred was determined. The pH values of the nanoparticles in aqueous solutions were determined and the zeta potentials of the nanofluids were inferred.
The obtained laboratory results show that aluminum oxide nanoparticles is the most effective that can trap migrating fines and prevent them from further migration in sand. The estimated mass of fines captured by aluminium oxide nanoparticles in about 80cm3 volume of sand in distilled water, brine, ethanol and diesel were about 0.63g, 0.52g, 0.8g and 0.94g respectively in the presence of crude oil. The results also revealed that the presence of crude oil affects the performance of the nanoparticles because in the absence of crude, the results were better. The pH of aluminum oxide nanoparticles in aqueous solutions gave the lowest values ranging from 2.5 to 3.6 and this could partly be responsible for the good performance of the compound in trapping migrating fines in sand.
Derivative-Free Generalized Field Development Optimization
Authors: Isebor Obiajulu J. 
Published: September 2013

Abstract
Given the substantial costs and potential rewards associated with petroleum field development and reservoir management, it is essential that these operations be performed as close to optimally as possible. This paper addresses problems where the goal is to simultaneously determine the optimal number and type of new wells, the sequence in which they should be drilled, as well as their corresponding locations and time-varying controls. The optimization is posed as a mixed-integer nonlinear programming (MINLP) problem involving categorical, integer and real-valued variables. The formulation handles bound, linear, and nonlinear constraints, with the latter treated using filter-based techniques. Noninvasive derivative-free approaches are applied for the optimizations. Methods considered include Mesh Adaptive Direct Search (MADS, a local pattern search method), Particle Swarm Optimization (PSO, a global search technique), a PSO-MADS hybrid and Branch and Bound (B&B, a rigorous search procedure that requires relaxation of the categorical variables). Two example cases involving channelized reservoir models are presented. The PSO-MADS hybrid is shown to outperform the standalone MADS and PSO procedures. In the example case in which B&B is applied, the PSO-MADS approach is shown to give comparable solutions but at much lower computational cost. This is significant since B&B provides near-exhaustive search capabilities. It is concluded that the methodology presented here appears to be applicable for realistic petroleum field development and reservoir management.
Integrated Evaluation of Thermo-Chemical Injection in Carbonate Reservoirs
Authors: Karbouj Omar M. 
Published: September 2013

Abstract
This paper provides an integrated evaluation study of thermo-chemical injection in heavy oil carbonate reservoirs. The objective of this study that is established through an optimum development plan is to appraise the possibility of improving the recovery factor and production rate of these reservoirs in an economic way, which will help to extend the productive life and profits of many neglected heavy oil reservoirs. This paper will share the work flow of planning, designing, and evaluating the experimental work and simulation studies of the project.
Within the study, a reservoir example of a large carbonate Middle Eastern reservoir that may utilize advanced production of heavy oil using thermo-chemical flooding is presented. Thorough investigations are carried out by employing several analyses to the aforementioned technique as it is considered the scope of this project. To approach this goal, a number of core flooding experiments are conducted on oil and rock samples obtained from the reservoir under the same conditions of the pressure and temperature measurements. Specific equipment required for the experiments are designed and assembled in order to accomplish these operations.
Fluid characterization is done for the oil, and the prepared chemical solutions. Along with this, rock properties of the used core samples are examined. The performed experiments are operated with different chemical concentrations that are analyzed to determine the best combination based on the economic studies. The applicability of thermal process during the chemical injection has been also examined by several experimental runs. Implementing this type of techniques will give an extra benefit to the reservoir by reducing its oil viscosity. This reduction will yield to a substantial increment in the oil production and therefore will maximize the oil recovery.
In order to clarify the impact of the used techniques on the reservoir, the rock sample properties are checked intensively throughout the flooding processes. Several geological tests are also conducted on the cores before and after the application of the experiments to determine whether the samples are affected or not.
Experimental Investigation of the Influence of Molecular Surface Interactions on Imbibition in Shale Nano-Pore Proxies
Authors: Kelly Shaina 
Published: September 2013

Abstract
Applicable flow regimes and diffusion as well as nano-pore capillary and surface force interactions are topics of great interest for fluid flow in unconventional reservoirs. Liquid flows in shale nano-pores have been wholly less subject to investigation than gas flows. Yet, the study of liquid and multi-component flows at the nano-scale is very important for understanding the interaction of free and bound water with hydrocarbons in shale systems, liquid-driven core analysis methods, and the fate of injected liquids (such as "fracking fluids") into the reservoir. The Young-Laplace equation for capillary pressure and the Washburn equation for imbibition rate are successfully applied in conventional media and have been applied to shale as well. Pore sizes are on the order of nanometers in shale, a scale that is theorized to mark a threshold for new transport phenomena considerations. This work investigates imbibition with various fluids - ketones, alcohols, aqueous solutions, and alkanes - at the nano-scale and reveals compelling evidence that long range intermolecular, electrostatic, and solvation surface interactions play a significant role in nano-capillary imbibition. Experiments are conducted in a pore size distribution of unconnected, fabricated silica and borosilicate glass nanochannels, which serve as a proxy for water-wet nano-pores in shale. The calculated capillary pressures based on the directly measured experimental results for imbibition lengths differ from the macroscopically predicted results by one order of magnitude. Additionally, in many fluid cases, the trend of the capillary pressure curves derived from the data show a decrease in capillary pressure with a decrease in channel size, or a "dewetting trend." This trend is contradictory to the prediction of the Young-Laplace formula. Accordingly, as the size of the pores decreases the relative scale of surface interactions increases, possibly leading to a departure from a regime dominated by Laplacian pressure to one strongly influenced by disjoining pressure. A positive correlation is found between the saturation of the imbibing fluid into the bundle of nanochannels and the calculated, unique disjoining pressure of the fluid.
New Comprehensive Equation to Predict Liquid Loading
Authors: Luo Shu 
Published: September 2013

Abstract
Liquid loading occurs in most of marginal natural gas wells. Many models have been developed to predict the inception of liquid loading. Detailed review of these models and comparison between droplet model and film models are presented in the paper. The results show that film model is more accurate for predicting liquid loading than droplet model. This indicates that film reversal may be the main reason of liquid accumulation in the wellbore. A new model is developed, which includes non-uniform film thickness around pipe. The model is able to improve the prediction of liquid loading, especially for inclined wells.
Different models are examined using both field and lab data. Film model shows much better agreement with the data than droplet model. The effect of inclination angle is validated using Veeken's field data. The new film model shows a significant improvement compared to droplet model as well as other film models.
Experimental Analysis on Bidispersed Cuttings Transport in Laminar Pipe Flow
Authors: Mulchandani Vijay Ashok 
Published: September 2013

Abstract
In drilling operations, cuttings transport is one of the crucial tasks performed by the drilling fluid. To be able to predict the true volumetric flow rate of the cuttings it is necessary to understand how the momentum is transferred from the fluid to the particles. This has been the subject of research for more than a century. However, there are still open questions. Due to high apparent viscosities of the fluid, cuttings are typically transported under laminar flow conditions. Moreover, the particle equivalent diameters are far from uniform and polydispersed suspensions and non-Newtonian fluids need to be considered. Many empirical correlations have been obtained to predict the transport of cuttings. However, the results are limited to flow systems similar to the ones analyzed. A better understanding of the transport mechanisms would help to obtain more general predictive tools.
In this contribution, we present an experimental setup used to measure fluid velocities and bidispersed particle velocities and position distributions. The particle image velocimetry (PIV) and the particle tracking velocimetry (PTV) methods are used to obtain flow fields of several bidispersed suspensions with varying particle diameter ratio and concentration. The results supply locally averaged fluid and particle velocity profiles and fluctuations of the particle velocities in the axial directions. These allow us to evaluate the effect of polydispersity on momentum transfer. Furthermore, histograms of the particle positions are used to investigate the effect of velocity gradients on the lateral distributions of semi-dilute suspensions. The results will be used for the development and validation of constitutive relations used in multiphase numerical methods such as the two-fluid model.
Secretion of Glucose-Dependent Insulinotropic Polypeptide in Patients With Type 2 Diabetes
Authors: Calanna Salvatore , Christensen Mikkel , Holst Jens J. , Laferrère Blandine , Gluud Lise L. , Vilsbøll Tina , Knop Filip K. 
Published: September 2013

OBJECTIVETo investigate glucose-dependent insulinotropic polypeptide (GIP) secretion in patients with type 2 diabetes and nondiabetic control subjects during oral glucose or meal tests.RESEARCH DESIGN AND METHODSEligible trials were identified by The Cochrane Library, MEDLINE, Embase, and Web of Science. Data were retrieved and random-effects models for the primary meta-analysis, random-effects meta-regression, and subgroup and regression analyses were applied.RESULTSRandom-effects meta-analysis of GIP responses in 23 trials during 28 different stimulation tests showed that patients with type 2 diabetes (n = 363) exhibited no significant differences (P = not significant) in peak plasma GIP, total area under the curve (tAUC), time-corrected tAUC (tAUC × min−1), and time-corrected incremental area under the curve (iAUC × min−1) in comparison with nondiabetic control subjects (n = 325) but had lower GIP responses as evaluated from iAUC (weighted mean difference, −648 pmol/L × min; 95% CI, −1,276 to −21). Fixed-effects models meta-analyses confirmed most of the results of the primary meta-analysis but showed iAUC × min−1 to be reduced and showed tAUC and tAUC × min−1 to be higher in diabetic patients. Random-effects meta-regression of the primary meta-analysis showed that age (peak GIP, tAUC, iAUC, and iAUC × min−1), BMI (tAUC, iAUC, and iAUC × min−1), and HbA1c (iAUC and iAUC × min−1) predicted some of the GIP outcomes. Post hoc subgroup analysis showed a negative influence of age and of HbA1c on GIP responses and showed a positive influence of BMI on GIP responses.CONCLUSIONSOur results suggest that patients with type 2 diabetes are characterized by preserved GIP secretion in response to oral glucose and meal tests. They also suggest that high BMI is associated with increased GIP responses but increasing age and HbA1c are associated with reduced GIP secretion.
Antidepressant Medication as a Risk Factor for Type 2 Diabetes and Impaired Glucose Regulation
Authors: Barnard Katharine , Peveler Robert C. , Holt Richard I.G. 
Published: September 2013

OBJECTIVE
Antidepressant use has risen sharply over recent years. Recent concerns that antidepressants may adversely affect glucose metabolism require investigation. Our aim was to assess the risk of type 2 diabetes associated with antidepressants through a systematic review.

RESEARCH DESIGN AND METHODS
Data sources were MEDLINE, Embase, PsycINFO, The Cochrane Library, Web of Science, meeting abstracts of the European Association for the Study of Diabetes, American Diabetes Association, and Diabetes UK, Current Controlled Trials, ClinicalTrials.gov, U.K. Clinical Research Network, scrutiny of bibliographies of retrieved articles, and contact with relevant experts. Relevant studies of antidepressant effects were included. Key outcomes were diabetes incidence and change in blood glucose (fasting and random).

RESULTS
Three systemic reviews and 22 studies met the inclusion criteria. Research designs included 1 case series and 21 observational studies comprising 4 cross-sectional, 5 case-control, and 12 cohort studies. There was evidence that antidepressant use is associated with type 2 diabetes. Causality is not established, but rather, the picture is confused, with some antidepressants linked to worsening glucose control, particularly with higher doses and longer duration, others linked with improved control, and yet more with mixed results. The more recent, larger studies, however, suggest a modest effect. Study quality was variable.

CONCLUSIONS
Although evidence exists that antidepressant use may be an independent risk factor for type 2 diabetes, long-term prospective studies of the effects of individual antidepressants rather than class effects are required. Heightened alertness to potential risks is necessary until these are complete.
Effects of pneumoperitoneum induced at various pressures on cardiorespiratory function and working space during laparoscopy in cats
Authors: Mayhew Philipp D. , Pascoe Peter J. , Kass Philip H. , Shilo-Benjamini Yael 
Published: September 2013

Abstract
Objective—To evaluate the effect of pneumoperitoneum on cardiorespiratory variables and working space during experimental induction of 3 intra-abdominal pressures (IAPs) in cats.
Animals—6 healthy young adult neutered male domestic shorthair cats.
Procedures—All cats were anesthetized through use of a standardized protocol. A catheter was placed in the right femoral artery for blood pressure and blood gas monitoring. A thermodilution catheter was placed in the right jugular vein via fluoroscopic guidance. Cardiopulmonary variables were measured before (baseline) and 2 and 30 minutes after initiation of pneumoperitoneum at IAPs of 4, 8, and 15 mm Hg; these were created through the use of a mechanical insufflator. At each IAP, abdominal dimensions (height, width, and circumference) were measured at a standardized location.
Results—At 4 mm Hg and 8 mm Hg IAP, no clinically important changes were identified in cardiorespiratory values. Heart rate, cardiac index, and stroke volume index remained unchanged throughout the study at all IAPs. Mean arterial blood pressure began to increase at 8 mm Hg and was significantly higher, compared with baseline, at both time points at 15 mm Hg. At 15 mm Hg, Paco2 was significantly higher and cats were more acidotic than at baseline. Working space was subjectively greater at 8 mm Hg than at 4 mm Hg IAP; however, at 15 mm Hg, no clinically important enlargement of the working space was identified, compared with at 8 mm Hg.
Conclusions and Clinical Relevance—Values of cardiopulmonary variables were largely unchanged by induction of pneumoperitoneum in healthy cats up to an IAP of 8 mm Hg, and no clinically important increases in working space were evident at an IAP of 15 versus 8 mm Hg. These findings provide little justification for use of IAPs > 8 mm Hg in healthy cats undergoing laparoscopic procedures; however, whether the situation is similar in diseased or elderly cats remains to be determined.
Influence of acidifying or alkalinizing diets on bone mineral density and urine relative supersaturation with calcium oxalate and struvite in healthy cats
Authors: Bartges Joseph W. , Kirk Claudia A. , Cox Sherry K. , Moyers Tamberlyn D. 
Published: September 2013

Abstract
Objective—To evaluate the influence of acidifying or alkalinizing diets on bone mineral density and urine relative supersaturation (URSS) with calcium oxalate and struvite in healthy cats.
Animals—6 castrated male and 6 spayed female cats.
Procedures—3 groups of 4 cats each were fed diets for 12 months that differed only in acidifying or alkalinizing properties (alkalinizing, neutral, and acidifying). Body composition was estimated by use of dual energy x-ray absorptiometry, and 48-hour urine samples were collected for URSS determination.
Results—Urine pH differed significantly among diet groups, with the lowest urine pH values in the acidifying diet group and the highest values in the alkalinizing diet group. Differences were not observed in other variables except urinary ammonia excretion, which was significantly higher in the neutral diet group. Calcium oxalate URSS was highest in the acidifying diet group and lowest in the alkalinizing diet group; struvite URSS was not different among groups. Diet was not significantly associated with bone mineral content or density.
Conclusions and Clinical Relevance—Urinary undersaturation with calcium oxalate was achieved by inducing alkaluria. Feeding an alkalinizing diet was not associated with URSS with struvite. Bone mineral density and calcium content were not adversely affected by diet; therefore, release of calcium from bone caused by feeding an acidifying diet may not occur in healthy cats.
Copper(I) π-complexes with allyl derivatives of heterocyclic compounds: structural survey of their crystal engineering
Authors: Slyvka Yurii , Goreshnik Evgeny , Pavlyuk Oleksii , Mys’kiv Marian 
Published: September 2013

Abstract
In this review an exhaustive crystallochemical analysis of copper(I) π-complexes with allyl derivatives of heterocyclic compounds has been performed. Structural genesis of inorganic constituents starting from the simplest units to the most complicated aggregates was considered taking into account the specific role of Cu-(C=C) interaction, the construction of the organic ligands, the basicity and nucleophilic activity of their heteroatoms, as well as olefin Cu(I) π-complex preparation route.
UV-absorption studies of interaction of karanjin and karanjachromene with ds. DNA: Evaluation of binding and antioxidant activity
Authors: Arshad Nasima , Rashid Naghmana , Absar Sajida , Abbasi Muhammad , Saleem Samreen , Mirza Bushra 
Published: September 2013

Abstract
Two flavonoids, karanjin (Kj) and karanjachromene (Kc) have been investigated spectrophotometrically for their mode of interactions with double stranded (ds)-DNA at blood (7.4) and stomach (4.7) pH and at human body temperature (37°C). Benesi-Hildebrand equation was used to evaluate the binding constants, K b . Binding constants at both pH values and at body temperature showed stronger binding of both the flavonoids and formation of 1:1 flavonoid-DNA complex via intercalative mode. However, K b values for karanjin were evaluated to be comparatively greater than karanjachromene at both pH values. The highest value of binding constant (1.32×105 M−1) for karanjin at blood pH (7.4) demonstrated its comparatively stronger binding and greater effectiveness at this pH. Standard Gibbs free energy changes (ΔG) of flavonoid-DNA complexes were calculated as negative values and indicative of spontaneity of their binding. Both flavonoids showed significant DNA protection activity.
New carbon from low cost vegetal precursors: acorn and cypress cone
Authors: Toscano Giovanni , Cimino Giuseppe 
Published: September 2013

Abstract
Thermal-treated carbons from acorn and cypress cone were prepared and characterized. The uptakes of heavy metal ions (Ag+, Cd2+ and Cr+3) and organics (phenol, methylene blue and sodium dodecylbenzenesulfonate) from aqueous solution have been studied. Effects of activation by HCl and HNO3 acids on the sorption properties of these carbons were investigated by mass titration, sorption isotherms, IRS, SEM and XRS. The models of Langmuir and Freundlich do not represent our sorption data very well. An earlier proposed empirical correlation is applied successfully to carry out a parameter of comparison between the studied carbons. The acidic treatment changes the surface chemical properties of the two thermal-treated carbons lowering their sorption performances. The carbons show good capacities to uptake metals, phenol and methylene blue, but sodium dodecylbenzenesulfonate is removed from its solutions to minor extent. The up-taking properties are found similar to those of two worldwide used commercial grade carbons.
Biosorption of reactive dye from aqueous media using Saccharomyces cerevisiae biomass. Equilibrium and kinetic study
Authors: Suteu Daniela , Blaga Alexandra , Diaconu Mariana , Malutan Teodor 
Published: September 2013

Abstract
The biosorption Brilliant Red HE-3B reactive dye by nonliving biomass, Saccharomyces cerevisiae, in batch procedure was investigated. Equilibrium experimental data were analyzed using Freundlich, Langmuir and Dubinin — Radushkevich isotherm models and obtained capacity about 104.167 mg g−1 at 20°C. The batch biosorption process followed the pseudo-second order kinetic model. The multi-linearity of the Weber-Morris plot suggests the presence of two main steps influencing the biosorption process: the intraparticle diffusion (pore diffusion), and the external mass transfer (film diffusion). The results obtained in batch experiments revealed that the biosorption of reactive dye by biomass is an endothermic physical-chemical process occurring mainly by electrostatic interaction between the positive charged surface of the biomass and the anionic dye molecules. The biosorption mechanism was confirmed by FT-IR spectroscopy and microscopy analysis