bluuebunny/crossref_metadata_2025_split huggingface dataset:
Copper oxide nanoparticles for thin film photovoltaics
Authors: Nuys Maurice , Flohre Jan , Leidinger Christine , Köhler Florian , Carius Reinhard 
Published: March 2013

ABSTRACTCommercially available tenorite (CuO) nanoparticles (NPs) were investigated in particular with respect to their suitability for photovoltaic applications. NPs with a diameter of about 30 nm were step wise annealed up to 1000°C in nitrogen atmosphere. The influence of the annealing treatment on the structural and electronic properties was investigated by Raman, photoluminescence (PL) and photothermal deflection spectroscopy (PDS) as well as X-ray diffraction measurements. Size, shape, and phase of the untreated NPs are analyzed by TEM measurements. The PL and PDS results show a strong increase of the tenorite band edge emission at about 1.3 eV accompanied by a decreasing sub gap absorption with increasing annealing temperature up to 700°C. According to literature, a phase transition from tenorite to cuprite (Cu2O) was expected and observed after annealing at 800°C. Strong cuprite band edge emission at about 2 eV accompanied by very weak defect and possibly tenorite band edge emission was found for samples annealed at 800°C and 1000°C.
Real-Time Investigation of NanoFET Current Surge Capability During Heavy Ion Irradiation
Authors: Xie Kan , Hartz Steven Allen , Ayres Virginia M. , Liu Zhun , Jacobs Benjamin W. , Baumann Thomas , Ronningen Reginald M. , Zeller Albert F. , Tupta Mary Anne 
Published: March 2013

ABSTRACTThe real-time electronic performance of a gallium nitride nanowire-based field effect transistor was investigated at five-minute intervals over thirty minutes of continuous irradiation by Xenon-124 relativistic heavy ions. An initial current surge that resulted in device improvement rather than device failure was observed. The current surge, and subsequent electronic behavior, was modeled using a combined thermionic emission-tunnelling approach, leading to information about barrier height, carrier concentrations, expected temperature behavior, and tunnelling.
Electrical Signature of Ion-Implantation Induced Defects in n-Silicon in the Defect Cluster Regime Studied using DLTS and Isothermal Transient Spectroscopies
Authors: Singh Samarendra P. , Rao Vineet , Mohapatra Y. N. , Rangan Sanjay , Ashok S. 
Published: March 2013

AbstractWe study electrical signature of defect clusters in KeV Ar ion-implanted n-silicon using Deep Level Transient Spectroscopy (DLTS) and isothermal capacitance spectroscopies such as time analyzed transient spectroscopy (TATS) and high resolution Laplace-DLTS. The samples are annealed at relatively low temperatures of 350 °C - 600 °C at which defect clusters are known to form and evolve. Contrary to the view that few dominant point-defect like traps are associated with defect clusters, our results show that the band gap may be replete with bands of multiple trap states; however their occupation and hence observation depends on experimental conditions dictated by dynamics of carrier capture and emission at these traps. Charge redistribution among multiple states and deepening of effective emission energy with capture are shown to be commonly occurring at these defects. Isothermal transient spectroscopy is shown to be appropriate tool for recognition of some of these features.
Formation and Properties of Three Copper Pairs in Silicon
Authors: Estreicher S.K. , West D. , Pruneda J.M. , Knack S. , Weber J. 
Published: March 2013

AbstractCopper in silicon is a feared contaminant in device processing. It diffuses quickly as an interstitial and forms electrically active precipitates that are difficult to dissolve. Several complexes assigned to copper pairs have been observed but have yet to be unambiguously identified and fully characterized. We present the results of joint theoretical-experimental studies of several pair structures. The theoretical work involves ab-initio molecular-dynamics simulations, and the results include configurations, binding energies, electronic structures, vibrational modes and formation dynamics. The experimental work combines electrical and optical techniques. One characteristic of the photoluminescence spectra is the presence of phonon replicas that imply the existence of very similar low-frequency and localized vibrational modes in two distinct copper pairs. These modes are theoretically identified.
Large Bore Expandable Liner Hangers for Offshore and Deepwater Applications Reduces Cost and Increases Reliability: GOM Case History
Authors: McCormick John , Carter Alexis , Johnson Rick 
Published: March 2013

Abstract
Reducing rig time and material costs for offshore wells is critical to a project's financial profitability. With the dramatic increase in the number of deepwater wells, new technologies and methods are needed to quickly and reliably complete wells. A case history of five deepwater large bore expandable liner hangers (ELHs) from late 2011 through the first half of 2012 in the Gulf of Mexico (GOM) show consistent material cost savings, reduced installation time, improved reliability, and increased versatility over conventional liner hanger systems. Four of these ELH systems were run off drill ships and one off a platform. A picture of the large bore ELH system is shown in Fig. 1.
The technological advances of ELH systems have increased well life and improved safety during liner installations over traditional systems. Sealing capabilities with expandable systems have evolved beyond conventional tools and the smooth radial flowpaths allow for greater ease of installation. A series of redundant sealing elements provide a gas tight liner top seal. Also, with the ELH system, rotation and reciprocation while cementing are possible.
This paper will describe offshore wells and the common problems associated with running intermediate liners. Expandable liner hanger technology will be explored to increase operator awareness of this beneficial technology. A comparison of ELH technology and the conventional systems in the same field are described within this paper.
Well Bore Collision Avoidance and Interceptions - State of the Art
Authors: de Wardt John P , Mullin Steve , Thorogood John L , Wright John , Bacon Robert 
Published: March 2013

Abstract
This paper highlights key knowledge that was shared at the SPE Collision Avoidance and Well Interceptions Applied Technology Workshop held in Inverness, September 2012. It has been written to raise awareness of critical issues concerning well bore collisions and interceptions.
Planning to ensure well collisions do not occur during drilling is a complex and demanding task which is often not given the high priority it requires in drilling programs. Assumptions are made of the validity and accuracy of historical data which is unfounded. Conversely, planning well interceptions when required in operations such as relief wells / drainage intercept wells requires a sound working knowledge of wellbore positioning technologies and techniques.
Well bore interceptions and proximity placement are becoming critical applications for development of some reservoirs, specifically tar sands and coal bed methane. Well bore collision avoidance is entering the everyday skills requirement of drilling engineers as they plan more infill wells and more cluster (pad) drilling. Ultimately, demonstrating knowledge of the bore hole position during the whole drilling process is becoming more of a regulatory requirement that demands greater understanding by the drilling engineering community and drilling / asset managers. Are drilling engineers trained, competent and adhering to procedures designed to manage the intricacies of well bore surveying requirements as applied to collision avoidance and well interceptions?
The workshop covered the topic under the following headings:
Survey database integrity. Collision avoidance management. Practical directional drilling. Relief well design. Interception techniques.
The outcome of the workshop was to emphasize that wellbore collisions must be treated as high risk events with serious consequences that must be managed through systematic survey management procedures. Borehole position errors are a critical input to subsurface modeling and can have a major impact on field economics. Several members of the workshop committee are also members of the SPE Wellbore Positioning Technical Section that has published two SPE papers providing the industry with the ellipse of uncertainty error models commonly referred to as the Industry Steering Committee on Wellbore Survey Accuracy (ISCWSA) models.
The Evolution of Wired Drilling Tools: A Background, History and Learnings from the Development of a Suite of Drilling Tools for Wired Drillstrings
Authors: Craig A. D. , Jackson T. A. , Ramnarace D. , Schultze R. , Briscoe M. 
Published: March 2013

Abstract
This paper will summarize the development of a range of drilling tools for use in a wired drillstring. The paper will focus on the history and learnings from the engineering design, field use and commercialization of wired conventional drilling tools including jars and underreamers as well as the development of an advanced drilling dynamics measurement capable of transmitting downhole data through the wired drillpipe network.
Wired drillstrings enable broadband bi-directional telemetry and along-string measurement capabilities for drilling and other well operations. Communication across the drillstring is achieved through the use of passive inductive coils placed in the pin and box shoulders connected by an armored coaxial cable which spans the length of the component.
Connection of conventional Measurement While Drilling (MWD) and Logging While Drilling (LWD) tools to the wired drillstring network requires that all components above these tools be wired as per this process. In a typical BHA this will include basic components such as Heavy Weight Drill Pipe (HWDP), drill collars and various subs but more internally complicated components such as drilling jars and underreamers.
The development of wired variants of these tools has required innovative engineering solutions, field testing and design revisions to ensure a reliable tool performance. This paper will summarize this process for both the development of a range of wired drilling jars and a wired underreamer.
The paper will then summarize the development of an advanced drilling dynamics measurement tool. The tool features a full suite of dynamics measurement including shock & vibration, downhole RPM, downhole torque, Weight on Bit (WOB) and bending moment. With telemetry provided by a wired drillstring this tool has the capability to provide real-time data with quality and definition orders of magnitude higher than conventional drilling dynamics tools. A series of examples of real-time data provided by this tool will also be presented and discussed.
Detect Kicks Prompted by Losses and Direct Measurement Well Control Method through Networked Drillstring with Along String Pressure Evaluation
Authors: Veeningen Daan 
Published: March 2013

Abstract
Traditional well control methods rely on surface measurements to identify a kick or wellbore influx. While most well control events occur during underbalanced conditions, an influx may be prompted by major vugular losses, typically caused by a carbonate vug. During such incidents, overbalanced drilling conditions plunge and the bottomhole pressure equalizes to pore pressure in the vug. An influx at surface is never experienced, as the annulus fluid level drops. Even filling the annulus does not prevent the BHP decrease and the resulting wellbore pressure is then approximately equal to the vug pore pressure minus the hydrostatic head. Since the drilling fluid gradient exceeds the formation pressure gradient, an underbalance is created along the exposed carbonate wellbore section. Hydrocarbons may enter, flowing down towards the vug along with the displacing fluid, until the wellbore pressure is equal to the formation pressure.
This paper describes efficient detection of well control events, both in underbalanced and overbalanced conditions, which is especially relevant for deepwater operations as the reaction time is significantly less than with surface BOPs. A methodology is offered to detect the annulus fluid level in conditions of unknown hydrostatic column height and fluid density through the use of discrete annular pressure acquisition along a networked drillstring. The downhole real time pressure evaluation also provides for monitoring of the gas migration to manage annular filling while losses continue to be experienced. Further, the ‘direct measurement method’ is offered for well control based on constant bottomhole pressure through downhole pressure measurements independently from surface measurements.
Basis of Design and Specifications for Shallow Water Arctic MODU for Year-round Operation, Development and Exploration
Authors: Shafer R. S. , Noble P. N. , Cheung T. O. , Chow Y. Y. , Quah M. , Foo K. S. , Wang C. D. , Perry M. J. 
Published: March 2013

Abstract
In Arctic offshore areas where exploration and production of hydrocarbons may occur, a substantial portion lies in water depths less than 50 meters. Currently there are no MODU's which can drill all different well types, production and exploration, over a wide range of water depths from 10 m to 50 m, ice conditions, and facilitate alternative development plans, using wellhead platforms. ConocoPhillips Company, in cooperation with Keppel, Offshore and Marine and Technology Centre, have developed a basis of design and specifications for a Self elevating Arctic Mobile Offshore Drilling Unit (MODU) for use in these water depths capabilities to drill a wide range of wells.
Economics require that a new build Arctic MODU be highly productive and operate nearly year-round. The Basis of Design and specifications result in a MODU that would have a wide range of application, be highly productive, and make alternative field development concepts viable.
The focus of this paper is to detail major items that impact the size, weight, and configuration of an Arctic MODU. This will result in a conceptual unit design that will be used in determine ice loads, layout, and structural design of the Arctic MODU.
Remote Operations Center - An Efficient and Highly Competent Environment to Optimize Operational Performance and Reduce Risk
Authors: Thorsen Arve K. , Sæverhagen Erland , Dagestad Jan Ove 
Published: March 2013

Abstract
Since the late 1990s, remote operations centers have focused on infrastructure and remote data gathering as some of the key resources in the intelligent oil field. Data gathering has low direct value unless used to mitigate risk and enhance operational efficiency. Rigsite experts work under the framework of health safety and environment (HS&E) and operational progress, with limited ability to analyze data. There is limited value in data gathering without real-time analysis of the information. This analysis is becoming one of the most important factors of daily work in remote operations centers. Real-time analysis is performed by multi-disciplinary teams, and remedial action can be taken immediately to mitigate risk. This is the strength and force of the operational centers; available interpretation technologies and time to perform the tasks in an environment without the rigsite stress factors.
During traditional operations, the wellsite personnel are responsible for the well and for ensuring nothing hazardous occurs, or taking action before or after an unwanted occurrence. In many cases, this is too late. Operations center planning, modeling and analysis – to avoid unwanted situations - are all part of the operational procedure, providing trends and thresholds for procedure change prior to an incident.
The wellsite personnel determine indications of well instability with potential to lead to extensive use of resources to ensure stable conditions. This is often based on experience and local knowledge.
The onshore team focuses on proactive processes to ensure the overall operational progress is conducted in a safe manner.
To illustrate data gathering and risk mitigation of a remote operational center, the BEACON center concept is used to display rigsite workflow, data analysis and feedback for maximum progress and minimum risk. Subsurface knowledge through drilling optimization and BHA reliability will be covered.
A Breakthrough Performance for an Inland Application with a Hybrid Bit Technology
Authors: Di Pasquale M. , Calvaresi E. , Pecantet S. 
Published: March 2013

Abstract
This paper describes the field experience of a new hybrid bit based on proven polycrystalline diamond compact (PDC) bit designs with rolling cutters on the bit periphery. A hybrid bit can drill shale and other plastically behaving formations up to three or four times faster than a roller-cone bit by being more aggressive and efficient.
The penetration rate of a hybrid bit responds linearly to revolutions per minute (RPM) unlike roller-cone bits, which have an exponential response with an exponent of less than one. In other words, the hybrid bit drills significantly faster than a comparable roller-cone bit in motor applications. Another benefit is the effect of the rolling cutters on the bit dynamics.
Compared to conventional polycrystalline diamond cutter bits, torsional oscillations are as much as 50% lower; stick/slip is reduced at low RPM, and whirl at high RPM. This gives the hybrid bit a wider operating window and greatly improves toolface control in directional drilling.
The hybrid drill bit technology combines roller-cone and PDC bits into a single patented design, employing the best attributes of each bit type to improve reliability and efficiency, while ensuring performance consistency in the most problematic applications. This revolutionary technology has a large spectrum of applications, excelling in typically troublesome formations for PDC and roller-cone bits, such as interbedded hard and soft stringers or hard nodular inclusions.
The results of a field test in an inland application will be presented, comparing the performance of hybrid bits with conventional PDC and roller-cone bits used on offset wells.
A planning and engineering process was applied, ensuring high-quality support to the operator in the office and at the rigsite. The client saved multiple conventional tungsten carbide insert bit runs and drilled 100% farther, ultimately achieving a rate of penetration (ROP) two times faster than the best tungsten carbide insert (TCI) bit run in the same well.
Analysis of Potential Bridging Scenarios During Blowout Events
Authors: Willson S. M. , Nagoo A. S. , Sharma M. M. 
Published: March 2013

Abstract
This paper demonstrates how simulation of wellbore pressures during different blowout scenarios; borehole stability analysis and solids transport can be applied to the problem of blowout risk assessment. This is a technology area that previously has been overlooked by petroleum geomechanics practitioners. The proposed analysis methodology emphasizes the importance of understanding the transient evolution of the kick within the borehole, as this is a key factor in assessing whether bridging is likely to occur during the events leading up to a blowout. Three representative situations are analyzed and conditions leading to self-killing are reviewed. Analyses of a shallow-gas kick and blowout reproduce the numerous field observations that self-killing is likely from the combination several possible mechanisms – borehole collapse of soft shales, sand erosion leading to cavity collapse in the initially-overpressured aquifer zone, gas depressurization and brine influx. For deeper water scenarios a sudden failure of the marine riser while drilling-ahead is expected to result in conditions where self-killing occurs. The rapid reduction in wellbore hydrostatic pressure following the loss of the riser margin is considered sufficient to initiate borehole failure that causes a cavings-loading that chokes the hydrocarbon influx, so allowing settling of the entrained solids and plugging of the borehole. In contrast, a more slowly-evolving swabbed kick is not expected to be self-killing. Here the slow progression of borehole instability is not expected to impede the increasing kick flow-rate. It is hoped that by presenting these analyses the industry may become better informed of the geomechanical and borehole stability aspects of kicks and blowouts, and that as a consequence well designs in deep-water can become more robust and inherently safer.
Design Aid for Charting a Drilling Automation Roadmap
Authors: Zamora Mario , Hildebrand Ginger 
Published: March 2013

Abstract
1202 PROGRAM ALARM This disturbing alarm, displayed to the men on location and in a remote center during the most critical part of the operation, signaled that the onsite computer system was no longer able to handle its automated multitasking requirements. The crew was forced to assume manual control to complete the operation, but not without continued assistance from onsite computers and engineers monitoring the event in the remote center. A short time later came the announcement heard by 600 million people around the world - "Houston, Tranquility Base here. The Eagle has landed. " Neil Armstrong had safely landed the Apollo 11 Lunar Module on the Moon.
Automation, perhaps the most game-changing opportunity in drilling today, is improving operational safety, efficiency, quality, and economics. More importantly, automation is making possible the execution of operations and activities difficult or even impossible for rig crews to complete using traditional methods. Notable recent success notwithstanding, the uptake of automation could be accelerated by the creation of industry-wide and segment-specific technology roadmaps to define short- and long-term goals and track progress. While most technology roadmaps are extensive and detailed documents, they must be built on a solid foundation that represents an overall view of the technology. Presented in this paper is a new design aid developed precisely for creating and displaying this view. For drilling automation in general and any number of specific operations and supporting technologies, the design tool can visually illustrate current and future (desired) states and the path(s) connecting the two. This visual approach also serves to catalyze discussion of this important topic.
The design tool presented here is a radically different way to create a technology roadmap overview. It is based on the common ternary chart, a triangular diagram that graphically depicts the composition of three-component systems. For drilling automation, the three components are rig equipment automation, rigsite manpower, and engagement from remote operation centers. Proportions of the three variables total 100% by definition. Simply stated, this means that a reduction of personnel on board, for example, must be balanced by increased automation of rig equipment and/or a higher level of engagement from remote operation centers.
The primary objective of this paper is to describe the underlying technology of this drilling-system automation design aid and to demonstrate how it can be used for real-world applications. There is no intent to present hard data that could be used directly to generate automation roadmaps for drilling.