bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Two Kinds of Refiners on the Solidification Structure and Property of Invar Alloy
Authors: Zheng Hong-guang , Yao Li-jiang , Xu Heng 
Published: April 2013

AbstractThe solidification structure of two 500 g cylindrical ingots of Fe-36Ni invar alloy, which were melted in a carbon tube furnace and cast adding Ce and Zr-Ti refiners respectively, were investigated. The results showed that the grain size became smaller. With the increase of refiner content, the ratio of equiaxed grains of ingot increased and the equiaxed grain size decreased. As for the 100 kg flat ingot, which was melted in a vacuum induction furnace and cast with Ce and Zr-Ti refiners respectively, the situation was different slightly. When adding Ce the dendritic grain diameter of the flat ingot became finer and the equiaxed grain ratio remained low; however, the mechanical property deteriorated. While adding Zr-Ti complex refiners, the solidification structure of the alloy was improved dramatically. Therefore, the mechanical properties at room temperature of as-cast flat ingots were improved. Furthermore, its high temperature ductility range expanded and the expansion coefficient of its hot-rolling plate remained almost the same.
Electrochemical Impedance Spectroscopy Studies of Corrosion of Two-phase Ni-Dy Alloys in Molten (0.62Li,0.38K)2CO3 at 650 °C
Authors: Liu S.N. , Su W. , Lv W.Y. , Wei Z.F. , Zeng C.L. 
Published: April 2013

AbstractThe dissolution of the NiO cathodes and the corrosion of bipolar plates are great obstacles to the commercialization of molten carbonate fuel cells (MCFC). Rare earth element dysprosium is effective in inhibiting the corrosion of Ni in molten carbonates. In this presentation, electrochemical impedance spectroscopy was employed to study the corrosion behavior of two-phase Ni-Dy alloys containing 1 and 3 wt.% Dy, respectively, in molten (0.62Li,0.38K)﻿2CO3 at 650 °C in air. The experimental results indicate that the Nyquist plots for the corrosion of both Ni-1Dy and Ni-3Dy are all composed of a small capacitive loop at high frequencies and a line at low frequencies, but with larger impedance values for Ni-3Dy. The emergence of Warburg impedance at low frequencies suggests that the corrosion of alloys is controlled by the diffusion of oxidants in molten carbonates, as observed for pure nickel. The addition of dysprosium to nickel can decrease its corrosion rate, with a better effectiveness for the 3% Dy addition. Based on the diffusion impedance, the oxidants involved in corrosion are also discussed.
Assessment of non-conflict related marital quality from the perspective of Chinese adolescents
Authors: Fok Hung-Kit , Shek Daniel T.L. 
Published: April 2013

Abstract
An indigenous Chinese measure of non-conflict related marital quality attributes from the perspective of adolescent children was developed. Based on a comprehensive literature review and focus group interviews of social workers and adolescents, 14 categories of themes (i.e., respect, appreciation, responsibility, trust, body touch, togetherness, intimacy, communication, acceptance, concern, criticism, consistency, helping, and response) were identified, and a scale assessing adolescent perception of inter-parental non-conflict related attributes was developed. A panel of experts was formed to determine the relevance, clarity and representativeness of the developed items to assess the content validity of the measure, after which the views of the experts were used to further refine the scale. The findings showed that the final 60-item measure had high relevance, clarity, and representativeness of the construct of non-conflict related attributes in inter-parental relationships. The developed measure is a pioneering effort in both Chinese and international contexts.
Clinical risk factors for complete and partial placental retention – a case-control study
Authors: Klar Maximilian , Laub Martina , Schulte-Moenting Juergen , Proempeler Heinrich , Kunze Mirjam 
Published: April 2013

Abstract

Objective: We sought to investigate the incidence, maternal risk factors, and perinatal outcomes of women with complete and partial placental retention in a tertiary care teaching hospital in Southwestern Germany.

Study design: We performed an unmatched case-control study with cases occurring between July 2000 and June 2007. Women were included into the study if they completed at least the 24th week of gestation and were diagnosed with placental retention requiring surgical intervention. We selected two controls per case and performed univariate and multivariate logistic regression analyses to identify risk factors for complete and partial placental retention.

Results: A total of 161 cases (2.02%) were identified out of 7978 deliveries. The 1-year prevalence of all types of placental retention continuously increased during the 6-year study period from 0.93% to 3.26%. A significant independent risk factor for all types of placental retention in the multivariate logistic regression model was a previous retention of the placenta [odds ratio (OR)=21.723, 95% confidence interval (CI) 6.07–77.7]. Independent protective factors against all types of placental retention were a non-anterior and non-posterior placenta location (OR=0.561, 95% CI 0.35–0.91), and a cesarean delivery with (OR=0.193, 95% CI 0.09–0.40) and without labor (OR=0.482, 95% CI 0.27–0.86). Women without partial placental retention delivered neonates with better 5-min APGAR scores (OR=0.78, 95% CI 0.65–0.95).

Conclusion: A thorough medical history and a vigilant prepartum ultrasound help in identifying women at risk for placental retention.
Estimating player contribution in hockey with regularized logistic regression
Authors: Gramacy Robert B. , Jensen Shane T. , Taddy Matt 
Published: April 2013

AbstractWe present a regularized logistic regression model for evaluating player contributions in hockey. The traditional metric for this purpose is the plus-minus statistic, which allocates a single unit of credit (for or against) to each player on the ice for a goal. However, plus-minus scores measure only the marginal effect of players, do not account for sample size, and provide a very noisy estimate of performance. We investigate a related regression problem: what does each player on the ice contribute, beyond aggregate team performance and other factors, to the odds that a given goal was scored bytheirteam? Due to the large-p(number of players) and imbalanced design setting of hockey analysis, a major part of our contribution is a careful treatment of prior shrinkage in model estimation. We showcase two recently developed techniques – for posterior maximization or simulation – that make such analysis feasible. Each approach is accompanied with publicly available software and we include the simple commands used in our analysis. Our results show that most players do not stand out asmeasurablystrong (positive or negative) contributors. This allows the stars to really shine, reveals diamonds in the rough overlooked by earlier analyses, and argues that some of the highest paid players in the league are not making contributions worth their expense.
A review of nanotechnology development in the Arab World
Authors: Alfeeli Bassam , Al-Rawashdeh Ma’moun , Bumajdad Ali , Al Lawati Haider , Abdelgawad Mohamed , Baccar Zouhair M. , Salem Issam Ben , Benaskar Faysal 
Published: April 2013

AbstractA growing number of initiatives on nanotechnology research, education, and industry have been recently launched by several Arab countries to quickly build scientific capacity and track worldwide developments in nanotechnology. Some countries, namely, the oil-rich countries, have allocated large funds to support these initiatives, which are intended to serve the national interests in energy, water and food supply, medicine, and local industry. The other Arab countries are also pursuing nanotechnology, however, with fewer funds but with more human resources. This study assesses the current status of nanotechnology in the Arab Republic of Egypt, Hashemite Kingdom of Jordan, Kingdom of Morocco, Kingdom of Saudi Arabia, Republic of Tunisia, State of Kuwait, State of Qatar, Sultanate of Oman, and the United Arab Emirates (UAE). The study is aimed at having a top-level overview of the status of existing, underdevelopment, and planed educational and research programs relevant to nanotechnology. The overview also includes nanotechnology research focus areas, challenges, and opportunities.
Säkularisierung oder Individualisierung von Religion?
Authors: Wilke Annette 
Published: April 2013

Zusammenfassung
Der Artikel wirft einen religionswissenschaftlichen Blick auf soziologische Theorien zu Religion und Moderne und neuere empirische Befunde,1 und diskutiert dabei auch die inhärente Eurozentrik wirkmächtiger Theoriekonstrukte. Primärer Fokus ist die kontrovers geführte Debatte, ob sich die religiöse Gegenwartskultur Europas durch Säkularisierung oder Individualisierung auszeichne. Diese Frage ist nicht nur eine der Empirie, vielmehr sind auch der perspektivische Blick und der Religionsbegriff entscheidend, ob Religion wahrgenommen wird oder nicht. Dies tangiert v. a. sogenannt postmoderne Spiritualität, deren Ausdrucksformen mit einem herkömmlichen Religionsbegriff, der sich an offizieller, institutionalisierter Religion (insb. dem Christentum) orientiert, nicht erfasst werden können. Heute sind sie jedoch gerade auch unter Kirchenmitgliedern zu finden. Dies ist einer der teilweise überraschenden Befunde der länderübergreifenden quantitativen Erhebungen des Religionsmonitor 2008. In einem ersten Teil des Artikels werden die Resultate und ihre ganz unterschiedlichen Auswertungen dargestellt und analysiert. Ein zweiter Teil thematisiert wirkmächtige Modernetheorien und die Adaptions- und Wandlungsprozesse in der Theoriebildung, die sich unter dem Druck der Empirie (insb. politischer Ereignisse) zu ständigen Neujustierungen gezwungen sah – bis hin zum heutigen Hang, die Säkularisierungs- wie auch die Privatisierungsthese aufzugeben oder umzucodieren.
Relationship between serum TSH levels and intrarenal hemodynamic parameters in euthyroid subjects
Authors: Tsuda Akihiro , Inaba Masaaki , Ichii Mitsuru , Ochi Akinobu , Ohno Yoshiteru , Nakatani Shinya , Yamada Shinsuke , Mori Katsuhito , Tahara Hideki , Ishimura Eiji 
Published: April 2013

ObjectiveLow thyroid function may be associated with a reduced glomerular filtration rate (GFR) calculated on the basis of creatinine metabolism. Thyroid hormone directly affects serum creatinine in muscle and low thyroid function might exert a similar direct effect in the kidney. The goal of the study was to evaluate this possibility by assessment of the inulin-based GFR and to examine the mechanism underlying the reduction of GFR.Patients and methodsRenal and glomerular hemodynamics were assessed by simultaneous measurements of plasma clearance of para-aminohippurate (CPAH) and inulin (Cin) in 26 patients with serum creatinine <1.00 mg/dl and without thyroid disease. All subjects were normotensive with or without antihypertensive treatment and were kept in a sodium-replete state. Renal and glomerular hemodynamics were calculated using Gomez's formulae.ResultsSerum TSH, including within the normal range (0.69–4.30 μIU/ml), was positively correlated with vascular resistance at the afferent arteriole (Ra) (r=0.609,P=0.0010), but not at the efferent arteriole (Re). Serum TSH was significantly and negatively correlated with renal plasma flow (RPF), renal blood flow (RBF), and GFR (r=−0.456,P=0.0192;r=−0.438,P=0.0252;r=−0.505,P=0.0086 respectively). In multiple regression analysis, serum TSH was significantly positively associated withRaafter adjustment for age and mean blood pressure.ConclusionsThese findings suggest that low thyroid function, even within the normal range, is associated with reduced RPF, RBF, and GFR, which might be caused by a preferential increase inRa.
Serpentinite Carbonation for CO2 Sequestration
Authors: Power Ian M. , Wilson Sasha , Dipple Gregory M. 
Published: April 2013

Abstract
Serpentinites offer a highly reactive feedstock for carbonation reactions and the capacity to sequester carbon dioxide (CO2) on a global scale. CO2 can be sequestered in mined serpentinite using high-temperature carbonation reactors, by carbonating alkaline mine wastes, or by subsurface reaction through CO2 injection into serpentinite-hosted aquifers and serpentinized peridotites. Natural analogues to serpentinite carbonation, such as exhumed hydrothermal systems, alkaline travertines, and hydromagnesite–magnesite playas, provide insights into geochemical controls on carbonation rates that can guide industrial CO2 sequestration. The upscaling of existing technologies that accelerate serpentinite carbonation may prove sufficient for offsetting local industrial emissions, but global-scale implementation will require considerable incentives and further research and development.
Detection of Bypassed Pay Zones and Water Production Control of Sandstone Reservoirs Using TDT and CHFR Logs
Authors: Hamada G. M. 
Published: April 2013

Abstract
Reservoir saturation monitoring, through cased wells, usually is the main key factor for proper reservoir management and recovery optimization in the cases of developed and mature oil fields. Thermal decay time tool (TDT) has been the main technique used for monitoring the inter wells water saturations in developed reservoir. One of the main problems that encountered while using TDT log is the reservoirs with low formation water salinity, this problem may also appear in reservoirs that are supported by water injection projects, in which the formation water is diluted by the injected water. This problem has been solved by combining TDT technique and cased hole formation resistivity tool (CHFR).
The ability to detect and evaluate bypassed hydrocarbon and monitor fluid movement in sandstone reservoir is a vital question to improve production and increase recovery. It is difficult to interpret the TDT data in reservoirs with low-salinity sandstone formation water. This problem cannot be solved because TDT measurements depend on the salt content in formation brine. Instead the cased hole formation resistivity tool (CHFR) is proposed to overcome the limitations associated with pulsed-neutron tools. This paper presents case studies of pay zones-saturation monitoring obtained from TDT and CHFR logs recorded in wells in mature sandstone reservoir which suffers from high water cut. The results are referenced to open-hole resistivity logs to monitor the vertical movement of reservoir fluids. It was found that water saturations calculated from CHFR logs are more accurate than TDT log in most cases. Water shut-off remedial action to manage water production from producing sections in the studied wells has been much more successful based on CHFR / TDT logs than the proposed remedial action based only on TDT data interpretation.
Overcoming Challenges while Acidizing Sandstone Formation Successfully in the Gulf of Cambay, Offshore India
Authors: Stolyarov Sergey , Alam Anwar 
Published: April 2013

Abstract
In the early days of the oilfield, matrix acidizing was considered useful only for stimulating carbonate formations. However it has been known for many years that with proper job design, acid and additive choices, and in-depth study of potential formation damage sources, matrix acidizing can safely and successfully stimulate production in sandstone formations. By incorporating carefully designed tubing pickle, pre-flush, main acid system and post-flush (including optimum doses of corrosion inhibitors, mutual solvents, iron control agents, clay control additives, surfactants, etc.), matrix acidizing can provide excellent productivity improvements even in sandstone formations with complex mineralogy.
This paper describes a matrix acidizing campaign executed successfully in the Gulf of Cambay (Khambhat) on the west coast of India. In initial laboratory tests and during simulation runs, it was aimed to design a pre-flush, acid system and post-flush to best suit the challenging reservoir conditions while also considering offshore logistics. Further as the formation had iron-rich minerals like chlorite clay, siderite, etc., a chemically modified organic sandstone acid system was selected as opposed to conventional hydrofluoric acid system. Moreover a spacer system was designed and pumped to push any iron precipitation far away from the near-wellbore area and to clean the area for the organic acid system.
After pumping the system in one well, the system design, pumping procedures and volumes were modified to further improve results in the next well. Fines-stabilizing agents were introduced to avoid clay migration or swelling that may otherwise jeopardize a successful treatment. The paper will explain the basis for modifying the design and pumping procedure, based on lessons learned from the prior operation.
Case Study on Handling Paraffinic and Viscous Crude of Mangala Oil Field of Rajasthan-India
Authors: Zalawadia Hardik , Pawde Chaitanya 
Published: April 2013

Abstract
The Mangala oil field, discovered in 2004 is one of the largest onshore oilfields in India. The field is divided into five reservoir units and contains approximately 1.3 billion barrels of STOOIP. The field currently produces around 175,000 BOPD. The oil is highly viscous, with high paraffinic content, a high pour point, high Wax Appearance Temperature (WAT), as well as high wax dissolution temperature. In addition, high CO2 content, sand production and a high water cut are some of the other notable problems. Keeping this in mind, a combination of innovative technologies had been envisaged right from the development and appraisal stage of the field. The technologies used have been reviewed from a flow-assurance point of view and possible reasons for the selection of these techniques over other methods are also investigated and presented.
The waterfloods, EOR pilots, artificial lift systems as well as surface facilities have been designed and implemented keeping in mind the nature of the crude. From a flow assurance point of view, techniques such as hot water injection, coiled tubing heater string, jet pumps etc. have been used extensively. A 670 km long pipeline has been laid from the field to Bhogat in Gujarat for transporting the crude. This pipeline is the world&#39;s longest independent heated section pipeline and makes use of another innovation called Skin Effect Heat Management System (SEHMS). A careful examination of these techniques can help us gauge whether they can be put to use to handle similar crudes in other parts of the world.
This being a review paper, the working methodologies of flow assurance techniques used for the Mangala crude and the reasons for their success are studied.
Application of TRIZ Methodology in Research and Development of Oilfield Technologies
Authors: Dass Chanchal , Gandhi Kanan 
Published: April 2013

Abstract
A technological revolution is going on in almost every sphere of modern life which is being possible due to regular and systematic innovations. In spite of this fact, there are few areas where there is no innovation or improvement in the system. Multiple zone well completion technology is one of such area. Over 100 years back, professionals started to develop an effective and efficient multiple zone well completion technology. But the dream of producing multiple zones encountered in a well, simultaneously, without causing inter well cross flow, remained a distant reality. This has not only resulted in poor productivity per well but has also created a bottleneck in the application of advanced technologies for secondary and tertiary recovery methods. Author has developed a technology for the production of all oil and gas bearing zones encountered in a well through a single completion without allowing any inter layer cross flow. Author is extensively using TRIZ methodologies and highly benefitted with the application of TRIZ-a systematic approach for solving problems which was developed in Russia during 1946. In multiple tubing, simultaneous and segregated production is possible but the total system becomes complex. In commingle production, system is simple but interlayer cross flow is a problem. Moving from conventional to unconventional thinking, a hybrid completion system has been developed which retains the advantages of multiple tubing completions and commingle production and eliminating the disadvantages of both the systems. In this paper author has tried to explain how TRIZ methodologies have helped him to develop an effective multiple zone well completion technology which will help other petroleum engineers to develop different innovative oilfield technologies using advanced innovative inventive tool like TRIZ.
A New Strategy to Explore Tight Oil/Gas Reservoirs "Fit for Purpose Acid Fracturing"
Authors: Hegazy G. M. , Salem Adel M. , Shedid Shedid A. , Shalaby Shouhdi E. , Abbott J.. 
Published: April 2013

Abstract
Oil and gas exploration in carbonate reservoirs typically utilize conventional techniques in perforation, matrix acidizing stimulation and well testing. Currently, oil companies have moved to more marginal reservoir targets. Application of these techniques has often yielded disappointing results and tighter zones are often abandoned for more promising target intervals.
With increases in oil and gas production targets, operators are being forced to investigate more marginal reservoir layers for reserves and production potential. The real challenge facing oil industry today is that successful exploration requires a change in drilling, completion and stimulation techniques currently utilized by operators.
Marginal reservoirs can have lots of resource potential and reserves, but may require horizontal well drilling, and/or multiple stage hydraulic fracturing to achieve economic production targets. This type of strategy is more expensive than conventional method(s) and is proven in some circles as potentially risky and many of these risks must be addressed and mitigated. In an effort to reduce risks and costs associated with the exploration process, a new stimulation strategy has been adopted for tight intervals to explore and appraise these intervals using vertical wells prior to going to horizontal wells.
This paper presents and analyzes oil exploration well case study in which a new strategy has been applied and evaluated. The study also demonstrates that this approach can lead to new resource discoveries, better reservoir understanding and improved well and completion design for future appraisal wells. Moreover, the paper highlights some of the additional challenges that this strategy may evoke and shows how these challenges may be overcome in the future.
Numerical Analysis of Influence of the Mold Material on the Distribution of Shrinkage Cavities
Authors: Dyja R. 
Published: April 2013

Abstract
Production of castings, like any other field of technology is aimed at providing high-quality product, free from defects. One of the main causes of defects in castings is the phenomenon of shrinkage of the casting. This phenomenon causes the formation of shrinkage cavities and porosity in the casting. The major preventive measure is supplementing a shortage of liquid metal. For supplement to be effective, it is necessary to use risers in proper shapes. Usually, the risers are selected on the basis of determination the place of formation of hot-spots in the castings. Although in these places the shrinkage defects are most likely to occur, shape and size of these defects are also affected by other factors. The article describes the original program setting out the shape and location of possible cavities in the casting. In the program is also taken into account the effect of temperature on the change in volume of liquid metal and the resultant differences in the shape and size of formed shrinkage cavities. The aim of the article is to describe the influence that have material properties of the mold on the simulation results.