bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiwell Deconvolution
Authors: Cumming J.A.. A. , Wooff D.A.. A. , Whittle T.. , Gringarten A.C.. C. 
Published: October 2014

Summary
In well-test analysis, deconvolution is used to transform variable-rate-pressure data into a single constant-rate drawdown suitable for interpretation. It is becoming part of a standard workflow for exploration and appraisal well-test analyses and in production-test analysis in which there are no interference effects from nearby wells. This paper develops and extends the single-well deconvolution algorithm of von Schroeter et al. (2004) to the larger and more-complex multiwell deconvolution problem. To validate the algorithm, it is applied to a synthetic example with known solution, and an uncertainty analysis is performed to quantify the impact of nonuniqueness on multiwell deconvolution. The use of the algorithm is illustrated further with a field example.
Beam-Pumping Operations: Problem Solving and Technology Advancements
Authors: Hein Jr. N.W. 
Published: October 2014

Distinguished Author Series
Distinguished Author Series articles are general, descriptive representations that summarize the state of the art in an area of technology by describing recent developments for readers who are not specialists in the topics discussed. Written by individuals recognized as experts in the area, these articles provide key references to more definitive work and present specific details only to illustrate the technology. Purpose: to inform the general readership of recent advances in various areas of petroleum engineering.

Abstract
Beam pumping is the most used, on-land artificial-lift method for petroleum production applications and has been since oil was discovered. Applications cover the full gamut of well types, including oil, water, and gas at depths from shallow to very deep, producing rates and volumes from low to high, viscous oil production, and dewatering-gas and coal bed-methane wells. Although beam pumping has become the "standard" lift method for on-land wells, the best engineering and operating practices still need to be followed to ensure cost-effective return on investment. When these best practices are not followed, continued operating problems, equipment failures, low efficiencies, and high operating costs often result. This paper presents some of the typical beam-pump engineering and operating practices that should be considered to obtain the most cost-effective operation over the life of the installation. Additionally, recent industry developments that are related to these practices are discussed.

Introduction
The selection of any artificial-lift method for an application depends on a variety of parameters that must be considered over the full life cycle of the installation to select the "best" lift choice. Ref. 1 discusses the selection procedure and parameters. This paper continues the discussion of the beam-pumping method that should be regarded as the standard lift technique and the first consideration for any on land production operation.
Beam pumping has the advantage of having wide exposure and its operation being known by many people around the world. Although this method has many benefits and practical applications, it should not be used for all producing operations. The practical operating range for beam pumping depends on many factors. There are some operating situations where an alternative lift method is being considered because beam pumps are having too many problems. On closer examination, what is often found is that the correct beam pump technology and best practices have not been used properly.
Fracturing Fluids - Then and Now
Authors: Jennings Alfred R. 
Published: October 2014

Summary
Fracturing fluid provides the means by which the hydraulic fracturing process can take place. All applications of well stimulation by fracturing must include selection of fracturing fluid in the initial phases of fracture design and treatment planning. Fracturing fluid has two important purposes:to provide sufficient viscosity to suspend and transport proppant deep into the created fracture system andto decompose, or break, chemically to a low viscosity to allow flowback of a major part of the fluid to the surface for fracture cleanup after the treatment is completed.
Because of the importance of its rheological properties and behavior in the fracture under reservoir conditions during (and immediately after) the treatment, service company research laboratories have spent millions of dollars on R&D of fracturing fluids.
Historical Advances, Pre-1960
Since the introduction of hydraulic fracturing for well stimulation in 1948, fracturing fluids have enjoyed a fascinating history. The first several hundred fracturing treatments consisted of relatively small volumes of oil-based fluids to carry graded sand into the created fracture. Initial treatments were conducted with lease crude to ensure compatibility of the fluid with the producing formation. Because of its availability following World War II and the applicability of the gelled-fluid technology to the hydraulic fracturing process, napalm became the first "second-generation" fracturing fluid. With careful mixing and proper timing (before the napalm could set up as a gelatinous solid), many successful fracturing treatments were conducted. The lower pump pressures with higher effective viscosity and proppant transport obtained with the gelled diesel or kerosene marked early acceptance of gelled-fracturing-fluid technology.
Variations in the quality of the gelling agent used to prepare the napalm-based gel caused inconsistent gelling rates and gel properties, which made the system extremely difficult to use. In the early 1950&apos;s, another gelled-oil system was developed by adding fatty acids and caustic to lease crudes and diesel oil. This use of the saponification (soap making) process to gel oils was widespread among the service companies of the day and allowed further advances in application of hydraulic fracturing. Although this method of gelation provided more dependable fluid characteristics than the napalm system, the saponification process was very sensitive to the presence of water in the lease crude being gelled.
Copula-based dependence measures
Authors: Liebscher Eckhard 
Published: October 2014

AbstractThe aim of the present paper is to examine two wide classes of dependence coefficients including several well-known coefficients, for example Spearman’s ρ, Spearman’s footrule, and the Gini coefficient. There is a close relationship between the two classes: The second class is obtained by a symmetrisation of the coefficients in the former class. The coefficients of the first class describe the deviation from monotonically increasing dependence. The construction of the coefficients can be explained by geometric arguments. We introduce estimators of the dependence coefficients and prove their asymptotic normality.
Land Managers’ Heterogeneity in Mediterranean Landscapes - Consistencies and Contradictions Between Attitudes and Behaviors
Authors: Barroso Filipe , Pinto-Correia Teresa 
Published: October 2014

Abstract
European rural landscapes face today several changes, which might indicate that an ongoing transition process is taking place. While these transition processes have been mainly addressed for Western Europe and landscapes dominated by intensive agriculture, they remain to be understood in Southern Europe, where large areas are occupied by extensive farming systems, maintaining a distinctive landscape character. However in Mediterranean areas, new ways of managing the land arise, no longer by the conventional farmers alone but also by a multiplicity of other land managers. Nevertheless, the dominant discourse in the farm sector, both in politics and in individuals, is still focused on production. Therefore to better assess the potential of land managers to adapt to changes and to meet the expectations that society articulates towards the farming sector, a description of the land managers’ diversity deserves a renewed attention. A number of questions remain unanswered or only partially answered. Which land managers are contributing more to the changes happening? Which are the drivers that encourage or prevent innovation and changes in the holdings? Do all farmers behave in the same way? Does the attitudes-thoughts get translated into actual behavior-actions? In order to answer these questions a land managers’ typology anchored on the multifunctional transition framework is proposed. It aims to understand which land manager type contributes more to the multifunctional transition bounded by non-productivist and productivist strategies in place. This typology exploits the combination between the behaviors-action in the holding and the expressed attitudes-thoughts. To achieve this typology, 373 questionnaires were completed by land managers in South Portugal. Results reveal in some cases inconsistencies between land managers attitudes and their action, in an opposite sense to what has been earlier identified in Northwestern Europe, and reflecting the heterogeneity of Mediterranean agriculture and land ownership. Thus, an understanding of the land managers types will lead us to a better understanding of what are land managers looking for in the landscape they use. This knowledge can support better oriented policies and management decision, certainly more easily accepted by land managers since their views, behaviors, attitudes and opinions are taken in consideration.
Natural Ecosystem-Units in Israel and the Palestinian Authority - Representativeness in Protected Areas and Suggested Solutions for Biodiversity Conservation
Authors: Rotem Dotan , Weil Gilad 
Published: October 2014

Abstract
The geographic location of Israel and the Palestinian Authorityon the border between Mediterranean and desert climate, and the strong topographic and geomorphological variation resulting from its position on the Great African Rift Valley, combine to sustain a great diversity of landscapes in a very small country. The purpose of this study is to determine whether the protected areas in Israel and the Palestinian Authority adequately represent the range of landscapes and ecosystems in the region.
Altogether, we defined 23 natural ecosystem-units in Israel and the Palestinian Authority, of which 17 are terrestrial landscapes and 6 are aquatic systems. In considering the adequacy of coverage in protected areas, we mapped Israel and the Palestinian Authority landscapes according to a set of environmental factors (climatic, geomorphological, geological and botanical) that we believe most effectively distinguish landscape types in this region. When the separation between adjacent units relies on sharp topographic or edaphic change in the landscape, the mapped units can be separated by a clear and sharp line. When adjacent units are actually a gradient of continuous environmental conditions the separation lines relied mostly on botanic characteristics.
The main land use categories in this analysis were urban areas, agricultural areas, nature reserves, national parks and forest reserves. For the first time in Israel and the Palestinian Authority, we quantified the different landscape types under the different categories of land use. This process, known as systematic conservation planning, allowed us to detect natural landscapes that are underrepresented in protected areas, and can guide decision makers to establish or improve management for the better representation of biodiversity.
Synthesis and Mossbauer studies of mesoporous γ-Fe2O3
Authors: Kotsyubynsky V. , Moklyak V. , Hrubiak A. 
Published: October 2014

Abstract
A method of synthesis of mesoporous γ-Fe2O3 by thermal decomposition of iron citrate has been proposed. Investigations of the crystalline and magnetic structure of obtained materials were done. Nanodispersed maghemite (γ-Fe2O3) with the sizes of coherent scattering regions of about 4–7 nm consisted of one phase only after gel sintering at 200, 250 and 300 °C. The particles of synthesized materials were both in magnetically ordered, and superparamagnetic states, and they formed a grid-like mesoporous structure. The influence of magnetic dipole interparticle interaction on the parameters of Mossbauer spectra was observed. A phenomenological model of the differences between nanodispersed γ-Fe2O3 magnetic microstructures obtained after annealing at different temperatures was presented.
Green synthesis of silver nanoparticles using tannins
Authors: Raja Pandian , Rahim Afidah , Qureshi Ahmad , Awang Khalijah 
Published: October 2014

Abstract
Colloidal silver nanoparticles were prepared by rapid green synthesis using different tannin sources as reducing agent viz. chestnut (CN), mangrove (MG) and quebracho (QB). The aqueous silver ions when exposed to CN, MG and QB tannins were reduced which resulted in formation of silver nanoparticles. The resultant silver nanoparticles were characterized using UV-Visible, X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), and transmission electron microscopy (TEM) techniques. Furthermore, the possible mechanism of nanoparticles synthesis was also derived using FT-IR analysis. Spectroscopy analysis revealed that the synthesized nanoparticles were within 30 to 75 nm in size, while XRD results showed that nanoparticles formed were crystalline with face centered cubic geometry.
In vitro evaluation of bioactivity of SiO2-CaO-P2O5-Na2O-CaF2-ZnO glass-ceramics
Authors: Riaz Madeeha , Zia Rehana , Saleemi Farhat , Bashir Farooq , Hossain Tousif , Kayani Zohra 
Published: October 2014

Abstract
Zinc is an essential trace element that stimulates bone formation but it is also known as an inhibitor of apatite crystal growth. In this work addition of ZnO to SiO2-CaO-P2O5-Na2O-CaF2 glass-ceramic system was made by conventional melt-quenching technique. DSC curves showed that the addition of ZnO moved the endothermic and exothermic peaks to lower temperatures. X-ray diffraction analysis did not reveal any additional phase caused by ZnO addition and showed the presence of wollastonite and hydroxyapatite crystalline phases only in all the glass-ceramic samples. As bio-implant apatite forming ability is an essential condition, the surface reactivity of the prepared glass-ceramic specimens was studied in vitro in Kokubo’s simulated body fluid (SBF) [1] with ion concentration nearly equal to human blood plasma for 30 days at 37 °C under static condition. Atomic absorption spectroscopy (AAS) was used to study the changes in element concentrations in soaking solutions and XRD, FT-IR and SEM were used to elucidate surface properties of prepared glass-ceramics, which confirmed the formation of HCAp on the surface of all glass-ceramics. It was found that the addition of ZnO had a positive effect on bioactivity of glass-ceramics and made it a potential candidate for restoration of damaged bones.
Role of substrate temperature on the growth mechanism and physical properties of spray deposited lead oxide thin films
Authors: Suganya M. , Balu A. , Usharani K. 
Published: October 2014

Abstract
Thin films of lead oxide were synthesized by cost effective spray pyrolysis technique at different substrate temperatures on glass substrates. Effect of substrate temperature on the growth mechanism and physical properties of the films was investigated. All the films were polycrystalline in nature with tetragonal structure corresponding to α-PbO. The films coated at 225 °C and 275 °C were (1 0 1) oriented, while the films deposited at 325 °C and 375 °C were (0 0 2) oriented. Above 375 °C, the pure tetragonal nature deteriorated and the peaks corresponding to orthorhombic phase were observed. The band gap value was found to be in the range of 2.3 to 2.62 eV. All the films had a resistivity of the order of 103 ohm-cm. A minimum resistivity of 0.0191 × 103 ohm-cm was obtained for the film coated at 325 °C. The activation energy increased with increase in substrate temperature.
CVD diamond layers for electrochemistry
Authors: Kowalska M. , Fabisiak K. , Wrzyszczyński A. , Banaszak A. , Szybowicz M. , Paprocki K. , Bała W. , Bylicki F. 
Published: October 2014

Abstract
Diamond electrodes of different morphologies and qualities were manufactured by hot filament chemical deposition (HF CVD) techniques by changing the parameters of diamond growth process. The estimation of diamond quality and identification of different carbon phases was performed by Raman spectroscopy measurements. The effect of diamond quality and amorphous carbon phase content on the electrochemical response of an obtained diamond electrode in 0.5 M H2SO4 as supporting electrolyte was investigated by cyclic voltammetry with [Fe(CN)6]4−/3− as a redox probe. The kinetic parameters such as catalytic reaction rate constant k0 and electron transfer coefficient α were determined. The obtained results show that the analytical performance of undoped diamond electrodes can be implemented just by the change of diamond layers quality.
Low-temperature synthesis of zeolite from perlite waste — Part I: review of methods and phase compositions of resulting products
Authors: Król Magdalena , Morawska Justyna , Mozgawa Włodzimierz , Pichór Waldemar 
Published: October 2014

Abstract
In this paper a review of the recent studies on the synthesis of zeolites from expanded perlite under hydrothermal conditions is presented. Attention is paid to possible outcomes of synthesis from low cost glass material, such as perlite. The study also investigates the phase composition of zeolitic materials obtained by modification of by-product derived from an expanded perlite production process. The synthesis was made using the hydrothermal method with sodium hydroxide under autogenous pressure at a temperature below 100 °C for 1 to 72 h. It was possible to obtain a zeolitic material at a temperature as low as 60 °C using 4.0 M NaOH. The X-ray diffraction pattern showed the biggest peak intensity of zeolite X with 4.0 M NaOH at the temperature of 70 °C. During synthesis at higher temperature zeolite Na-P1 (with 3.0 M NaOH at 90 °C) and hydroxysodalite (with 5.0 M NaOH at 90 °C) were obtained.
Hydrogen desorption kinetics of MgH2 synthesized from modified waste magnesium
Authors: Kantürk Figen Aysel , Coşkuner Bilge , Pişkin Sabriye 
Published: October 2014

Abstract
In the present study, hydrogen desorption properties of magnesium hydride (MgH2) synthesized from modified waste magnesium chips (WMC) were investigated. MgH2 was synthesized by hydrogenation of modified waste magnesium at 320 °C for 90 min under a pressure of 6 × 106 Pa. The modified waste magnesium was prepared by mixing waste magnesium with tetrahydrofuran (THF) and NaCl additions, applying mechanical milling. Next, it was investigated by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) techniques in order to characterize its structural properties. Hydrogen desorption properties were determined by differential scanning calorimetry (DSC) under nitrogen atmosphere at different heating rates (5, 10, and 15 °C/min). Doyle and Kissenger non-isothermal kinetic models were applied to calculate energy (Ea) values, which were found equal to 254.68 kJ/mol and 255.88 kJ/mol, respectively.
Properties of graphite-stainless steel composite in bipolar plates in simulated anode and cathode environments of PEM fuel cells
Authors: Włodarczyk Renata 
Published: October 2014

Abstract
The use of a graphite-stainless steel composite as bipolar plates (BP) in polymer electrolyte membrane fuel cells (PEMFCs) has been evaluated. The study covers measurements of mechanical properties, microstructural examination, analysis of surface profile, wettability, porosity and corrosion resistance of the composite. The corrosion properties of the composite were examined in 0.1 mol·dm−3 H2SO4 + 2 ppm F− saturated with H2 or with O2 and in solutions with different pH: in Na2SO4+ 2 ppm F− (pH = 1.00, 3.00, 5.00) at 80 °C. The performed tests indicate that the graphite modified with stainless steel can be a good choice to be used as a bipolar plate in PEM fuel cells.
Risk Factors Associated with Overweight among Adolescents in Serbia/ Dejavniki Tveganja, Povezani S Prekomerno Telesno Težo Pri Mladostnikih V Srbiji
Authors: Boričić Katarina , Simić Snežana , Vasiljević Nađa , Marinković Jelena 
Published: October 2014

Abstract
Introduction. The pandemic of obesity in adolescents is one of the challenges of public health.
Aim. The aim of this study was to examine the association of overweight with demographic, socioeconomic and lifestyle factors among Serbian adolescents.
Method. A cross-sectional study of 2139 adolescents aged 10 to 19 years was carried out. Data used in this study were from the 2006 Health Survey. In accordance with the international sex- and age-specific Body Mass Index cut-off points, all participants were classified as being normal weight or overweight, including obese. The association between the risk factors and overweight were examined using a multivariate logistic regression model.
Results. The study showed that 28.9% of boys and 17.0% of girls were overweight, while 14.5% of boys and 8.1% of girls were obese. Boys were more likely to be overweight/obese, compared with girls. Being younger (p< 0.01 for 14 to 15 years) and (p< 0.01, for 16 to 19 years), engaging in physical activities that last less than 7 hours a week, in such a manner that they breathe quickly and become sweaty, (p< 0.01) and skipping breakfast (p< 0.05) were risk factors significantly associated with overweight among adolescents. No significant association was found with wealth index.
Conclusion. These findings should be an integral part of further preventive interventions, especially oriented towards younger adolescents, who are physically inactive, have a habit of skipping breakfast and are boys.
Management of Gastrointestinal Disorders in Central and Eastern Europe: Self-Reported Practice of Primary Care Physicians / Zdravljenje Bolezni Prebavil V Srednji In Vzhodni Evropi: Podatki, Ki Jih Zdravniki V Primarni Zdravstveni Oskrbi Sami Sporočajo
Authors: Palka Małgorzata , Krztoń-Królewiecka Anna , Tomasik Tomasz , Seifert Bohumil , Wójtowicz Ewa , Windak Adam 
Published: October 2014

Abstract
Background. Gastrointestinal disorders account for 7-10% of all consultations in primary care. General practitioners’ management of digestive disorders in Central and Eastern European countries is largely unknown.
Aims. To identify and compare variations in the self-perceived responsibilities of general practitioners in the management of digestive disorders in Central and Eastern Europe.
Methods. A cross-sectional survey of a randomized sample of primary care physicians from 9 countries was conducted. An anonymous questionnaire was sent via post to primary care doctors.
Results. We received 867 responses; the response rate was 28.9%. Over 70% of respondents reported familiarity with available guidelines for gastrointestinal diseases. For uninvestigated dyspepsia in patients under 45 years, the “test and treat” strategy was twice as popular as “test and scope”. The majority (59.8%) of family physicians would refer patients with rectal bleeding without alarm symptoms to a specialist (from 7.6% of doctors in Slovenia to 85.1% of doctors in Bulgaria; p<0.001). 93.4% of respondents declared their involvement in colorectal cancer screening. In the majority of countries, responding doctors most often reported that they order fecal occult blood tests. The exceptions were Estonia and Hungary, where the majority of family physicians referred patients to a specialist (p<0.001).
Conclusions. Physicians from Central and Eastern European countries understood the need for the use of guidelines for the care of patients with gastrointestinal problems, but there is broad variation between countries in their management. Numerous efforts should be undertaken to establish and implement international standards for digestive disorders’ management in general practice.