bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coupling of subcritical methanol with acidic ionic liquids for the acidity reduction of naphthenic acids
Authors: Zafar Faisal , Mandal Pradip Chandra , Shaari Ku Zilati Bt Ku , Ullah Zahoor 
Published: October 2017

Abstract
The presence of naphthenic acids (NAs) in crude oil is the major cause of corrosion in the refineries and its processing equipment. The goal of this study is to reduce the total acid number (TAN) of NAs by treating them with subcritical methanol in the presence of acidic ionic liquid (AIL) catalysts. Experiments were carried out in an autoclave batch reactor and the effect of different reaction parameters was investigated. It was observed that TAN reduction was positively dependent on the temperature and concentration of the AIL whereas excess of methanol has a negative effect. Approximately 90% TAN reduction was achieved under the optimized reaction conditions using [BMIM]HSO4 as catalyst. It was also perceived from the experimental results that the AILs with longer alkyl chain exhibited higher catalytic activity. The activity and stability of AIL showed that they can be promising catalyst to esterify NAs under subcritical methanol.
Chiral pyrrolidinium salts derived from menthol as precursor – synthesis and properties
Authors: Janus Ewa , Gano Marcin 
Published: October 2017

Abstract
Six new chiral pyrolidinium salts with chiral substituent at quaternary nitrogen atom were synthesized with high overall yields from (-)-menthol as cheap chiral precursor and were identified by NMR and HRMS spectroscopy. It was shown that anion type had the effect on chemical shift of protons adjacent to quaternary nitrogen atom and physical properties of these salts. Salts with NTf2 or NPf2 were in a liquid state at room temperature and characterized with the highest thermal stability among others. Furthermore, chiral ionic liquid with NTf2 anion was used as solvent in Diels-Alder reaction and gave higher yield and stereoselectivity than in ionic liquids with achiral cations. Synthesized chiral salts have the potential as chiral solvents in synthesis and auxiliaries in analytical methods to improve chiral recognition.
Computational Investigation of Cationic, Anionic and Neutral Ag2AuN (N = 1–7) Nanoalloy Clusters
Authors: Ranjan Prabhat , Chakraborty Tanmoy , Kumar Ajay 
Published: October 2017

AbstractThe study of bimetallic nanoalloy clusters is of immense importance due to their diverse applications in the field of science and engineering. A deep theoretical insight is required to explain the physico-chemical properties of such compounds. Among such nanoalloy clusters, the compound formed between Ag and Au has received a lot of attention because of their marked electronic, catalytic, optical and magnetic properties. Density Functional Theory (DFT) is one of the most successful approaches of quantum mechanics to study the electronic properties of materials. Conceptual DFT-based descriptors have turned to be indispensable tools for analysing and correlating the experimental properties of compounds. In this report, we have investigated the ground state configurations and physico-chemical properties of Ag2AuNλ(N= 1–7,λ=±1, 0) nanoalloy clusters invoking DFT methodology. Our computed data exhibits interesting odd-even oscillation behaviour. A close agreement between experimental and our computed bond length supports our theoretical analysis.
Vortices at Microwave Frequencies
Authors: Silva Enrico , Pompeo Nicola , Dobrovolskiy Oleksandr V. 
Published: October 2017

AbstractThe behavior of vortices at microwave frequencies is an extremely useful source of information on the microscopic parameters that enter the description of the vortex dynamics. This feature has acquired particular relevance since the discovery of unusual superconductors, such as cuprates. Microwave investigation then extended its field of application to many families of superconductors, including the artificially nanostructured materials. It is then important to understand the basics of the physics of vortices moving at high frequency, as well as to understand what information the experiments can yield (and what they can not). The aim of this brief review is to introduce the readers to some basic aspects of the physics of vortices under a microwave electromagnetic field, and to guide them to an understanding of the experiment, also by means of the illustration of some relevant results.
Scaling morphosemantic transparency/opacity: A corpus-linguistic and acquisitionist study of German diminutives
Authors: Schwaiger Sonja , Ransmayr Jutta , Korecky-Kröll Katharina , Sommer-Lolei Sabine , Dressler Wolfgang U. 
Published: October 2017

AbstractThe judicious use of electronic corpora allows new possibilities in the study of word formation. In contrast to the usual way of contrasting morphosemantic transparency (or compositionality) and morphosemantic opacity (or non-compositionality) in a dichotomous way, we present a ten-step scale from maximum transparency to total opacity, exemplified with the common German diminutive suffixation in -chen and Austro-Bavarian -erl. Our corpus-linguistic investigation allows new insights into problems of distribution of type and token frequency according to degrees of morphosemantic transparency/ opacity and of the two rivalling diminutive formations. An analysis of diminutive acquisition is added as external evidence for or against previous claims. Acquisition data come from three longitudinal corpora and from 24 children of a transversal quasi-longitudinal study. Here the order of acquisition of diminutives according to the ten-step scale of morphosemantic transparency/opacity and to adult type and token frequency will be presented and the relation between morphosemantic and morphopragmatic meaning will be discussed.
Simulating the Thermal Impact of Masonry Ties
Authors: Asava Ryan , Rusu Zachary A. 
Published: October 2017

In masonry veneer wall assemblies, lateral ties are a structural requirement. Traditionally they are fabricated from steel, which has a high conductivity. Building codes require that ties be tightly spaced and, in most climate zones, it requires continuous insulation in the majority of wall assemblies. Continuous insulation in the cavity space results in the ties penetrating the insulation layer. The combination of material, required spacing, and location of insulation result in most masonry veneer walls being constructed with a significant amount of thermal bridges causing a loss in thermal performance.
At present, the building industry typically does not account for these thermal bridges and their effect on the exterior enclosure. We speculate that the reasoning for this is primarily due to a lack of industry accepted information relative to the thermal reduction of the masonry wall system from the inclusion of ties. The purpose of this paper is to begin providing this missing information. Using three dimensional Finite Element Modeling software (thermal modeling), common masonry wall assemblies are studied by simulating them with and without masonry ties. This comparative analysis quantifies the impact of masonry ties on the thermal performance of each wall assembly studied.
In recent history, large steps, such as continuous insulation requirements, thermally broken fenestration systems, low-e coatings, and air barrier technologies have been introduced to increase the performance of exterior enclosures and thus the overall efficiency of the built environment. The industry now must focus its attention on the details of wall systems to take the next steps in incrementally increasing building efficiency. Data obtained through three dimensional thermal modelling is used to address the impact masonry ties have on the thermal performance of wall systems. Finally, alternate materials are evaluated and considered as a means to improve thermal performance of the masonry veneer wall assemblies.
Long-Term Fragility of Y Chromosomes Is Dominated by Short-Term Resolution of Sexual Antagonism
Authors: Blackmon Heath , Brandvain Yaniv 
Published: October 2017

AbstractExisting models of sex chromosome evolution do not address whether inversions can accumulate even if they cause difficulties in meiotic pairing. Blackmon..The evolution of heteromorphic sex chromosomes has fascinated biologists, inspiring theoretical models, experimental studies, and studies of genome structure. This work has produced a clear model, in which heteromorphic sex chromosomes result from repeated fixations of inversions (or other recombination suppression mechanisms) that tether sexually antagonistic alleles to sex-determining regions, followed by the degeneration of these regions induced by the lack of sex chromosome recombination in the heterogametic sex. However, current models do not predict if inversions are expected to preferentially accumulate on one sex-chromosome or another, and do not address if inversions can accumulate even when they cause difficulties in pairing between heteromorphic chromosomes in the heterogametic sex increasing aneuploidy or meiotic arrest. To address these questions, we developed a population genetic model in which the sex chromosome aneuploidy rate is elevated when males carry an inversion on either the X or Y chromosome. We show that inversions fix more easily when male-beneficial alleles are dominant, and that inversions on the Y chromosome fix with lower selection coefficients than comparable X chromosome inversions. We further show that sex-chromosome inversions can often invade and fix despite causing a substantial increase in the risk of aneuploidy. As sexual antagonism can lead to the fixation of inversions that increase sex chromosomes aneuploidy (which underlies genetic diseases including Klinefelter and Turner syndrome in humans) selection could subsequently favor diverse mechanisms to reduce aneuploidy—including alternative meiotic mechanisms, translocations to, and fusions with, the sex chromosomes, and sex chromosome turnover.
Dual Roles of Glutathione in Ecdysone Biosynthesis and Antioxidant Function During Larval Development in Drosophila
Authors: Enya Sora , Yamamoto Chikana , Mizuno Hajime , Esaki Tsuyoshi , Lin Hsin-Kuang , Iga Masatoshi , Morohashi Kana , Hirano Yota , Kataoka Hiroshi , Masujima Tsutomu , Shimada-Niwa Yuko , Niwa Ryusuke 
Published: October 2017

Abstract
Ecdysteroids, including the biologically active hormone 20-hydroxyecdysone (20E), play essential roles in controlling many developmental and physiological events in insects. Ecdysteroid biosynthesis is achieved by a series of specialized enzymes encoded by the Halloween genes. Recently, a new class of Halloween gene, noppera-bo (nobo), encoding a glutathione S-transferase (GST) in dipteran and lepidopteran species, has been identified and characterized. GSTs are well known to conjugate substrates with the reduced form of glutathione (GSH), a bioactive tripeptide composed of glutamate, cysteine, and glycine. We hypothesized that GSH itself is required for ecdysteroid biosynthesis. However, the role of GSH in steroid hormone biosynthesis has not been examined in any organisms. Here, we report phenotypic analysis of a complete loss-of-function mutant in the γ-glutamylcysteine synthetase catalytic subunit (Gclc) gene in the fruit fly Drosophila melanogaster. Gclc encodes the evolutionarily conserved catalytic component of the enzyme that conjugates glutamate and cysteine in the GSH biosynthesis pathway. Complete Gclc loss-of-function leads to drastic GSH deficiency in the larval body fluid. Gclc mutant animals show a larval-arrest phenotype. Ecdysteroid titer in Gclc mutant larvae decreases, and the larval-arrest phenotype is rescued by oral administration of 20E or cholesterol. Moreover, Gclc mutant animals exhibit abnormal lipid deposition in the prothoracic gland, a steroidogenic organ during larval development. All of these phenotypes are reminiscent to nobo loss-of-function animals. On the other hand, Gclc mutant larvae also exhibit a significant reduction in antioxidant capacity. Consistent with this phenotype, Gclc mutant larvae are more sensitive to oxidative stress response as compared to wild-type. Nevertheless, the ecdysteroid biosynthesis defect in Gclc mutant animals is not associated with loss of antioxidant function. Our data raise the unexpected hypothesis that a primary role of GSH in early D. melanogaster larval development is ecdysteroid biosynthesis, independent from the antioxidant role of GSH.
Orietta Favaro y Graciela Iuorno, eds. 2013.La trama al revés en años de cambio. Experiencias en la historia argentina reciente. General Roca: Publifadecs, Cehepyc. ISBN 978-987-1549-59-7
Authors: Freire Adriana Jorgelina 
Published: October 2017

Orietta Favaro y Graciela Iuorno (editoras) presentan en esta última producción trabajos propios y de distintos académicos integrantes del Centro de Estudios Históricos de Estado, Política y Cultura (Cehepyc). Dicho Centro tiene funcionamiento enla Universidad Nacionaldel Comahue en Neuquén capital, Patagonia-Argentina.
An Experimental Investigation of the Effect of Gas and Water Slug Size and Injection Order on the Performance of Immiscible WAG Injection in a Mixed-Wet System
Authors: Alkhazmi Bashir , Sohrabi Mehran , Farzaneh S. Amir 
Published: October 2017

Abstract
Water-alternating-gas (WAG) injection is a widely used enhanced oil recovery (EOR) technique. The performance of WAG injection is affected by a number of design parameters; including the size of the gas and water injection slugs as well as their order of injection. Since the prediction of the impact of these parameters by numerical simulation lacks reliability, experimental data are needed to optimize the performance of WAG injection. In this work, we will present a comprehensive series of experimental data in which we investigate the impact of these design parameters on the performance of WAG injection in terms of oil recovery and injectivity.
A set of coreflood experiments have been performed in which the performance of WAG injection and the effect of pertinent parameters have been systematically investigated. To minimize laboratory artefacts, long and large cores were used to experimentally investigate various gas and water injection strategies, including WAG and SWAG injection, WAG injection with different slug size and order of gas and water injection. The experiments were performed on a mixed-wet rock using an immiscible gas/oil system.
Comparison of the results of WAG injection with different slug sizes shows a better efficiency and higher recovery performance for short water and gas slug injections compared to the large cycle injections. Reducing the size of the injected WAG slug enhanced oil recovery over that of the large slug size WAG injection, by 6.5 % (IOIP %). WAG injection produced more oil than water or gas injection alone. For the conditions of our experiments, WAG produced 9.0 % and 14.0 % more oil compared to waterflood and gas injection, respectively. The results also revealed that the order of fluid injection was important. When WAG injection started with a gas injection period followed by water injection, 6.0 % additional oil was recovered compared to WAG injection started by a water injection period. However, the large gap of oil recovery observed between LS-WAG (large slug WAG beginning with water) and LS-GAW (large slug WAG beginning with gas) became narrower after reducing the size of the injected slugs. Reducing the injected slug size appears to lead to higher oil recovery and approach the trend of oil recovery by SWAG injection. In other words, the amount of oil recovery observed for SWAG injection seems to present the upper limit of the small slug WAG tests.
A novel and new set of experimental data are reported in this paper. WAG injection is a special case of three-phase flow, which is known to be difficult to reliably simulate by the current reservoir simulators. Therefore, reliable experimental data are needed for better understanding of the complex physics involved in the process of oil recovery by WAG injection and for developing improved models and methodologies for predicting the performance of oil reservoirs under WAG injection.
Development of an Empirical Equation to Predict the Performance of CO2-WAG Flooding
Authors: Balhasan Saad , Al Kandari Bader , Omar Mohamed , Al-Otaibi Jassim , Al-Shakhis Hamad , Al Amer Ali 
Published: October 2017

Abstract
The Water Alternating Gas flooding method aims to improve sweep efficiency during CO2 flooding. This study has screened three waterflooded sandstone reservoirs for CO2 injection to apply the Stalkup Model. An empirical correlation is derived from the Stalkup Model parameters Sorw, Sob, Sorm, and HCPVI to ease estimation of the recovery factor calculation process. The empirical correlation is called the WAG correlation. The hydrocarbon recovery percent calculations of the reservoirs after 1.2 HCPVI were as following; for reservoir (A), the Stalkup Model provided a recovery percentage of 10.00% against the WAG correlation value of 9.30%. In reservoir (B), Stalkup Model calculations gave 6.00% compared to 6.40% from WAG correlation. Finally, in reservoir (C) the calculation showed a 7.00% form Stalkup Model and 6.40% from WAG correlation. The estimated average error for the three reservoirs was 7.4%.
Application of Nanotechnology in Oil Well Cementing
Authors: Baig Mirza Talha , Rahman Muhammad Kalimur , Al-Majed Abdulaziz 
Published: October 2017

Abstract
Nanotechnology provides a wide variety of methods to resolve industrial issues, which could not be addressed previously using customary methods. It helps enable researchers to alter properties of bulk materials at the nanometer scale. Various nanomaterials have been successfully applied in many areas of petroleum engineering, particularly in drilling fluids, lost circulation, enhanced oil recovery (EOR), and cementing. This study examines the mechanical and microstructural properties of oil well cement with nanozeolite.
During this research, API Class G cement was used with various concentrations of nanozeolite. Compressive strength development of Class G cement, with and without nanozeolite, was studied using an ultrasonic cement analyzer (UCA) for 24 hours under high-pressure and high-temperature (HP/HT) conditions. The porosity and permeability of set Class G cement admixed with nanozeolite was also analyzed in an automated permeameter/porosimeter after 24 hours of curing. Microstructural examination of cement samples was performed using scanning electron microscopy (SEM).
Three important parameters during well cementing operations included time to achieve 50- and 500-psi compressive strength and time to achieve 2,000-psi compressive strength. These parameters were significantly altered by adding a small percentage of nanozeolite to the neat Class G cement. The addition of nanozeolite resulted in a decrease in transition time and accelerated achievement of 2,000-psi strength. Furthermore, the porosity and permeability of the set Class G cement specimens with nanozeolite decreased substantially, thus indicating a dense microstructure of the matrix. This was confirmed by microstructural investigations using SEM. Nanozeolite is nonhazardous, nontoxic and is compatible with API Class G cement.
Nanozeolite can be an effective oil well cement additive because it enhances early strength, and the final compressive strength helps improve cement durability. The accelerated compressive strength development can help decrease wait-on-cement (WOC) time, thus lowering operation costs. Additionally, denser microstructure can help restrain the invasion of corrosive formation fluids.
Method to Measure Front End Loading FEL of Steam-Based Thermal Recovery Projects to Assess Impact of Reservoir Complexity, Uncertainty and Risk in Future Performance
Authors: Ortiz-Volcan J. L. , Shanat F. H. , Haider F.. 
Published: October 2017

Abstract
At early stages of front end loading (FEL) of steam-based thermal recovery projects, oil companies make critical strategic decisions with limited understanding on how reservoir complexity, uncertainty and risk could affect recovery and economic performance. A solution is to measure front end loading (FEL) and improving it to meet a minimum level of project definition for sound strategic decisions.
This paper presents a method to measure FEL by combining complexity and definition rating indices that account for a) reservoir structural, stratigraphic, rock, fluid, energy, static and dynamic complexity and b) definition rating indices and completeness of wells and surface infrastructure. Causal maps guide the assessment of complexity, uncertainty and risk in CAPEX, OPEX and cycle time of typical projects.
Sixty-eight factors in eight matrices provide complexity indices and twelve additional factors account for completeness and definition indices for wells and reservoir under static and dynamic conditions. Five hypothetical examples using actual field data from analogs, illustrate how the method works. A causal map describes cause and effect relationships of uncertainty and risk for typical ranges of CAPEX, OPEX and project cycle times which translate into probability of success (POS). Finally, general strategies provide guidelines to reduce uncertainties and mitigate risks.
By measuring and improving FEL companies increase the probability of success by mitigating risks such as higher operational expenditures (OPEX) to meet demand of energy, higher capital expenditures (CAPEX) for oversized processing facilities, and deferred production due to failures caused by extreme operating conditions imposed by high temperature, high pressure and corrosive contaminants.
This method confirms the benefits of measuring the level of definition of a project, which is a best practice used in aerospace, nuclear, chemical, and other complex industries. It also improves the level of inter-disciplinary communication typical of reservoir-well-surface systems in steam-based EOR projects.