bluuebunny/crossref_metadata_2025 huggingface dataset:
PROINT - Program for Excellence in Integrity Management for E&P
Authors: Ribeiro Joao Luiz Moreira , Frydman Bernardo , Jordan Paul Ricardo Daniel Rodriguez
Published: May 2011

With the raise of the oil prices most of production installations have their expect life extended. The aging of those installations brought to the companies a different approach regarding integrity, it has been necessary to create a management system capable to deal with this issue.

The PROINT is a Program for Excellence in Integrity Management for E&P installations. It started to be developed two years ago due to an internal diagnosis where it was founded an increasing degradation of the integrity of the production installations due to the rapidly growth in numbers of them in E&P in the last decade. The Program is based on PMBoK® Guide (Project Management Body of Knowledge) structure from the Project Management Institute. It has 15 knowledge areas with 58 work processes covering all issues related the management of the integrity. Besides procedures for each work process it has a Technical Guide to all main critical equipment which is a manufacturer manual rewritten by Petrobras technicians including the operation scenarios and the best practices in operation and maintenance. It can be applied to any installation of the Company, Petrobras has decided to start in all topside installations but it will be also implemented in our subsea installations. The main deliverable from the program is a Management System which is capable to comply with all requirements from the authorities and regulatory agencies, besides, of course, all topics related to integrity.

The Program will be implemented in the next four years in all Operations and Services Units in 14 phases. At the end, Petrobras can certify each Unit in Integrity Management, if desire.
An Example of Technologies and Methodology Applied to Deep-Water Geo-Hazard Assessment, Offshore Nigeria
Authors: Adamy Jerome , Unterseh Stephan , Grimaud Sylvie , Colliat-Dangus Jean-Louis , Lanfumey Valentine
Published: May 2011

1 Abstract

Improving our understanding of deep-water geo-hazards requires a long-term effort, which TOTAL has sustained over the last 20 years, in particular by carrying out joint R&D projects with "IFREMER", the French Marine Sciences Institute. The successful avenue has, consistently over time, yielded significant technical advances, in terms of data acquisition and data analysis.

The involvement of a wide range of specialists remains central to a properly robust analytical investigation of the processes governing the deep-water geo-hazards. The multi-disciplinary approach is also paramount to the technical specification of the acquisition program, for a campaign at sea where non-conventional instruments are deployed.

The paper presents geo-hazards targeted by the latest joint R&D project carried out by TOTAL and IFREMER, and the set of dedicated instruments deployed during the 2008 campaign, offshore Nigeria. Some significant improvements of the technology are introduced, as well as their impact in terms of geo-hazard evaluation.

2 Introduction

This paper presents an innovative approach to conducting an intensive deep-water geo-hazard study, offshore Nigeria, during the ERIG 3D joint 3-year R&D project (2007–2009). This project was directed and carried out by TOTAL and IFREMER. ERIG 3D is the last in a series of R&D projects aiming at identifying and understanding deep-water geo-hazards, namely projects GUINESS (1992–1995), ZAIANGO (1998–2002), and NERIS (2003–2005). Those projects were all conducted in collaboration by TOTAL and IFREMER.

During the course of ERIG 3D, a complex campaign at sea was conducted in 2008 with the oceanographic vessel "Pourquoi pas???, involving a wide variety of instruments, and allowing (1) the evaluation of some new equipments, only partly available in the industry, and (2) subsequent multidisciplinary studies of the deep-water geo-hazards that were targeted by the program of ERIG 3D (depth range 600–1,200 m).

The ultimate objective of the program was to validate (or invalidate) proposed new methodologies for the identification and better understanding of the deep-water geo-hazards. Two avenues of investigation were identified:technology improvements to enhance data quality, andmethodology upgrades, addressing both the offshore acquisition phase, and the assessment process.
Late-life Field Optimization, Canyon Express - A Case Study
Authors: Wells James Curtis , Zambare Neeraj
Published: May 2011

Canyon Express is a subsea gas gathering system in 7,200 ft water depth. It was the longest and deepest subsea tie-back at the time of its development (2000-2002). The Canyon Express System produces 40 – 60 MMSCFD and is well beyond its originally projected life. The infrastructure consists of two 12 in, 56 mile long flowlines that transfer gas from three separate subsea fields to a shallow-water production platform 56 miles away. The real-time Production Management System (ProdMS), which was designed specifically for Canyon Express, offers advantages that were presented in OTC 2007. This paper supplements the OTC 2007 paper and discusses how the ProdMS has been an important factor in production optimization over the past 4 years.

The ProdMS is a simple to use flow assurance tool which dynamically models the whole facility from the well screens to topsides gas sales. To assist in day-to-day operations and planning, the ProdMS provides various applications including an offline planning model, online subsea virtual metering, and hydrate margin prediction at every point in the flowlines.

The ProdMS has been used to reduce the amount of methanol injection for hydrate mitigation to less than one-third of the system's original dosage rate. Planning and monitoring of line sweeps to clear liquids were accomplished using the planning and real-time modes. Since the operating conditions of the pipeline system change depending on amount of production and fluid composition from each well, the ProdMS proved valuable to provide production forecasts of future wells at different operating conditions. It has been used as a virtual metering tool for all producing wells. It has also been used extensively as a day-to-day data monitoring tool onshore which allows the production engineer to supervise and monitor production facility changes remotely.

Real time ProdMS has been used to manage production efficiently at Canyon Express, a tough and challenging ultra deepwater environment, for more than five years. The ProdMS is one of the main factors in extending the life of the subsea fields by more than four years and will continue to be a production optimization tool until the end of project life.

Introduction

The Canyon Express Pipeline System consists of two 12 in flow lines running parallel from the Camden Hills Field through the Aconcagua and Kings Peak Fields to Canyon Station, a host platform located approximately forty miles north of the northernmost Kings Peak well. Production from the fields is gas with some condensate and formation water. The wells are tied together in a " daisy-chain?? arrangement. Refer to Figure 1: Canyon Express Infrastructure.
Lateral Buckling and Pipeline Walking Mitigation in Deep Water
Authors: Perinet Dominique , Simon Julien
Published: May 2011

The pipelines and associated structures are major components of the subsea deep water oil and gas production. Deep water production requires the transportation of multiphase hot products under high pressure and temperature. In deep water the soil is usually very soft clay of high plasticity with high water content. Both of these elements are major aggravating factors for pipeline instabilities: lateral buckling and pipeline walking. The paper presents and illustrates practical measures which are developed by the contractors for mitigating the risks of failures associated to these instability phenomenons. The analyses which are carried out for the lateral buckling and pipeline walking are generally very conservative. Such attitude is fully understandable with regards to the risks of failure in deep water. However the mitigation measures should not be inducing unwanted effects.

Introduction

The instability phenomenon associated to the variations of pressure and temperature become more acute in deep water fields. When dealing with lateral buckling and pipe walking it is considered safer to provide mitigation measures to prevent these conditions than attempting to design the pipeline system to accommodate the loads and displacements. With time contractors have developed different techniques to mitigate the risks. The purpose of this paper is to discuss the different techniques used in the industry. It will present also the negative effects which may be resulting from some measures and will describe some techniques which are new or nor yet in usage.

The pipeline displacements induced by pressure and temperature will result in stresses in the pipeline itself and the connection spools and subsea structures. The continuous production cycles of start up and shut down result in cyclic loading and progressive movements of the flowlines. This will result in cumulative fatigue damage to the flowlines, which, if not considered in the overall design of the flowline system, can lead to failure and rupture of the flowline. Failures may occur on different types of pipe: single pipe or pipe-in-pipe as illustrated in the Figure 1. The fracture surfaces are smooth indicating a fatigue failure with a number of cycles in the range of one hundred thousand to one million.
A Global Perspective on Biocides Regulatory Issues
Authors: Bradley Gregory , Mcginley Heather , Hermsen Nanette
Published: May 2011

Description of the Proposed Paper

This paper will review the regulations pertaining to offshore biocide use in different regions of the world. The roles of regional and global organizations in helping to harmonize available environmental, health, and safety information will also be discussed.

Application

Many offshore applications involve the use of biocides, including drilling, production, and pipeline operations. Biocides are also vital to reservoir integrity, flow assurance, and prevention of microbial corrosion. Regulation of the use and discharge of chemicals, including biocides, must be well understood in order to protect the environment and maintain compliance.

Results, Observations, and Conclusions

Each region, and in some cases each country, has its own method of evaluating risk for chemical use. These assessments lead to varying degrees of regulation throughout the world. In some cases there are additional regulations for offshore chemical use. It should be noted that several organizations exist which aim to standardize the risk assessment process for Biocides. The Organisation for Economic Co-operation and Development (OECD) publishes test protocols for its global member countries that are widely used for determining the ecotoxicity and other environmental parameters of chemicals. Regional guidelines are also in place in some areas; for example, North Sea countries have adopted the Harmonized Offshore Chemical Notification Format (HOCNF) to ensure that each country's regulatory agency is considering the same data set. Ultimately, each regulatory body is responsible for performing its own risk assessments and enforcing its own standards.

Significance of Subject Matter

For chemical suppliers, service companies, and asset owners who operate globally, it is important to be aware of how regulations vary from region to region. An understanding of the science behind these regulations can also lead biocide users to make informed, environmentally-conscious decisions.
Carbon Capture and Sequestration: Ascertaining CO2 Storage Potential, Offshore New Jersey, USA
Authors: Brown Alan Lee , Berlin Eric Hamilton , Butsch Robert John , Senel Ozgur , Mills Joseph , Harichandran Arutchelvi , Wang James Tak Ming
Published: May 2011

The onshore area of the Northeastern United States is lacking in reservoir intervals appropriate for storing large volumes of carbon dioxide (CO2). It is proposed that the geologic conditions found offshore of the Eastern Seaboard are conducive to the safe storage of large volumes of CO2 generated from anthropogenic activities in the region (Schrag, 2009). Little subsurface investigation has occurred in this area since it was initially explored for hydrocarbons in the mid-1970s. Can newer data evaluation techniques be applied to older data to ascertain the CO2 storage potential of the Atlantic Outer Continental Shelf?

Schlumberger Carbon Services recently performed an initial site evaluation of storage potential for CO2 within the Cretaceous intervals near the Baltimore Canyon Trough utilizing vintage wireline, core, and 2D seismic data to develop a geocellular model to simulate CO2 injection and storage. The evaluation site is centered approximately on the COST B-2 well, located about 70 miles offshore of New Jersey and drilled as a stratigraphic test in 1976. The COST B-2 well and others drilled in the late 1970s and 80s penetrated a Lower Cretaceous interval abundant in channel and mouth-bar sands deposited in a wave-dominated delta-front to nearshore depositional environment. Petrophysical analysis of available wireline data indicates these sands exhibit porosity and permeability ranges adequate for the potential injection of CO2. Additonally, log analysis indicates laterally extensive and vertically thick marine shales overly these potential reservoir intervals and provide an appropriate seal across the region. This petrophysical analysis was integrated with interpretations from available two dimensional seismic lines to investigate the spatial potential of the targeted sediments to store large volumes of injected CO2.

Introduction

In order to properly assess the potential for CO2 storage of any specific geologic formation at any specific geologic site, the primary attributes for the subsurface interval being investigated must be evaluated for storage potential. We will explain analysis of the key variables associated with the construction of a subsurface model that can adequately evaluate the potential Storage Capacity, Injectivity, and Containment for CO2 storage. The site being investigated in this study is located within the United States (U.S.) Atlantic Outer Continental Shelf (OCS), approximately 70 miles east of the upper New Jersey coastline in the vicinity of the COST B-2 well (Figure 1). For this initial assessment, vintage wireline, core, and two dimensional (2D) seismic data, acquired during exploration for hydrocarbons in the late 1970s and early 1980s at or near the proposed site, were utilized to develop a geocellular earth model and reservoir simulation model so that injection rates, plume size, well design, and construction costs could be estimated.
Produced Water - Impact and Analysis Challenges in Cold Regions
Authors: Hawboldt Kelly , Bottaro Christina , Thanyamanta W.
Published: May 2011

Produced water accounts for the largest volume in the production stage of offshore oil and gas operations. There are very few studies dedicated to investigating impacts of produced water discharge in Arctic/cold regions. As exploration expands into these regions, the effects of the cold temperatures, high motion, ice, and extended periods of sunlight on fate and toxicity of constituents will need to be more fully understood due to environmental concerns and production costs. The fate of discharged produced water is determined by dilution and mixing, volatilization/dissolution/sedimentation, and biochemical/chemical reactions. These transport/transformation mechanisms are not well characterized in cold environments. Low temperature and motion may affect efficiency of separation equipment and reduce natural biodegradation and evaporation. As a result, the type of constituents targeted in warmer climates may not be a concern in cold regions and may be replaced by other constituents. The first part of this paper will identify chemicals of concern in produced water for cold regions and model their fate in the environment. Due to the low temperatures, many of the contaminant transformations will be governed by equilibrium. Identification of the chemicals of concern leads into the second theme of this paper. Oil and grease is monitored for regulatory purposes however, what is defined as " oil and grease?? depends on analytical/sampling methods which vary between regions. For instance, some methods measure both the dispersed and the dissolved hydrocarbons, so measurements of dispersed oil tend to be " overestimated?? when compared against limits. Comparison of analytical data between platforms or building of annual trends is also complicated. Discrete sampling, when the sample analysis is done onshore, delays mitigation or corrective actions with respect to process control and does not give an accurate temporal trend in oil in water discharge. Using the information from the " identification and fate?? section of this work we have been developing molecularly imprinted polymers (MIPs) for highly selective isolation, detection and measurement of key constituents (e.g. alkylphenols) and are working toward devices to house the MIPs for online analysis. The development of these systems will allow the non-specialist to quickly identify constituents in the field and enable extensive data collection in real time and hence the knowledge to make informed and timely decisions.
Offshore Nova Scotia Play Fairway Analysis: 2D Basin Modeling Results
Authors: Colletta Bernard , Monnier Frederic , Rabary Guillaume , Doublet Stefan , Letouzey Patrick
Published: May 2011

This paper presents part of the modeling results obtained in the Play Fairway Analysis project launched in 2009 by OETRA that consists of an integrated geosciences approach in a collaborative program between academy and industry institutions. A 210 km long depth-migrated seismic line (NovaSPAN 1400) was interpreted in age, paleo-environments and lithology. The structural evolution was reconstructed to constrain the backstripping. Two major source rocks, Late Jurassic marine type II and Early Cretaceous terrestrial type III were identified from pyrolysis analyses. A third type II source, of Early Jurassic age has been inferred from the presence of Gammacerane biomarkers in the Venture B13 condensates, which were correlated with Pliensbachian source rocks and oils from the conjugate margin in Morocco and Portugal.

The interpreted section displays 3 structural domains: the little deformed shelf area, the strongly disturbed bathyal domain with complex salt tectonics structures and the flat lying strata domain of the abyssal plain.

Modeling results show that the Early Jurassic and Late Jurassic sources are presently in the gas and oil window respectively. Early cretaceous is immature. Expulsion and entrapment occurred lately and first significant accumulations appeared during the Cretaceous (about 80 Ma ago) and are still active today. Three potential plays can be considered for exploration:Late Jurassic carbonate bank with a risk of biodegradation due to low Present temperature (around 60°C);Early Jurassic carbonate ramp along the northern salt basin boundary,Hypothetical turbiditic sands in the Early Cretaceous (Logan Canyon equivalent)
A Super-Giant Offshore Field Development Plan Change from Steel Structures to Artificial Islands
Authors: Modavi Cyrus Abdulla , Al Muflehi Abdul Hakeem , Taemoom Ihaab , Al-Khateeri Bakheet S. , Noman Adil M.A.
Published: May 2011

The offshore giant oil field covers an aerial extent of approximately 1200 square kilometers. The field development to date has been based on pattern producer and water injection wells drilled from numerous Well Head Platform Towers (WHPT's) located through-out the field; these are connected via subsea pipelines to satellite platforms and an in-field central complex.

The field operator has a mandate to increase the production rate by 40% in the near future. If the current steel platform development plan were to be continued, numerous new WHPT's, additional thousands of kilometers of subsea pipelines, and significant facilities upgrades on existing satellites and the central processing platform would be required. The increasing complexity and cost of such an expansion motivated a major change of the development plan through construction of artificial islands and use of extended reach and long horizontal completions. The location of the field in water-depths ranging from 5 to 15 meters, allows cost effective construction of artificial islands. Also favoring application of artificial islands for the subject field is its long expected operating life (nearly 100 years) that exceeds the life of the existing steel platforms. The island concept provides enormous flexibility in managing future subsurface and surface uncertainties. The islands-based development will provide a low cost foundation for phased installation of facilities and allow space for future requirements, such as facilities for Artificial Lift, Gas Injection and other EOR applications. In short, for the case presented, artificial islands as drilling/production centers provide the following advantages:Provisions for cost-effective/phased facilities installationsEnhanced field operability, at lower OPEXReduced downtime lossesFlexibility to capture up-side potentials during field life cycleEnhance possibilities for future EOR applicationSignificant development cost reduction

In conclusion, where environmentally and economically viable, building artificial islands as drilling and production centers, offers numerous advantages over steel-base structures, which could even justify island construction within existing brown field infrastructures.

Introduction

The field is located 84 km offshore Abu Dhabi, as shown in Figure 1. It was discovered in the early 1960's and covers an aerial extent of approximately 1200 square kilometers. A simplified field cross section is shown in Figure 2.
Sable Sub Basin Near Field Exploration Prospectivity
Authors: Steele David Roger , Mulders John , Crisp Melanie
Published: May 2011

Exploration in the Sable Sub-basin shelf is relatively immature and still holds surprising near-field exploration prospectivity around the Sable Offshore Energy Project (SOEP) infrastructure. Shell and partners have drilled 19 exploration wells on the current Shell interest leases in the Sable Sub-basin from 1969 to 2001 and have discovered nearly 1BBOE. Exploration proceeded in 3 phases, an early phase of hydropressure exploration, a main phase of deep geopressure exploration, and a later phase of exploration in geopressures.

The early phase of exploration in hydropressures involved 5 wells from 1969 to 1975. Onondaga E-84, Triumph P-50, Thebaude P-84, Citnalta I-59, and Intrepid L-80 tested reservoir objectives ranging from the Late Jurassic MicMac Formation to the Early Cretaceous Upper Missisauga Formation. The discovered volume totaled 1.2 Tcf and 36MMBC. Drilling was suspended at the top of geopressures. Success at the top of geopressures in the Thebaude well encouraged deeper drilling in geopressures.

Discovery of the 1.5 Tcf Venture field in 1978 kicked off a phase of successful deep exploration in geopressures. Another 11 deep wells were drilled through 1985 and discovered another 2.65 Tcf in a series of moderate sized gas fields ranging from 130 to 437 Bcf. These fields include Arcadia, Glenelg, Olympia, Venture, South Uniacke, Alma, Chebucto, Venture West, and Triumph North. Hydrocarbons, primarily gas, were found in both geopressured and hydropressured reservoirs that ranged in age from the Late Jurassic to the Early Cretaceous.

The final phase of exploration resulted in only two wells since 1985, Sable South B-44 and Onondaga B-84, both resulted in discoveries. Most of the industry exploration in the basin since 1985 has focused on carbonate, not clastic plays.

The next phase of exploration remains to be tested by the drill bit. Fifty-five leads have been defined in the Sable Sub-basin around the Sable Offshore Energy Project (SOEP) infrastructure. All the leads are downthrown fault closures with shelf margin delta complexes as reservoirs. The combined factors of rapid subsidence, high sediment input from a large river, and proximity to the shelf margin result in thick geopressured reservoirs with multiple intra-formational seals and thick top seals. Fault closure traps occur along faults with large throw with potentially long columns. Several geopressured traps in the discovered fields have fault dependent columns ranging from 100m to 205m.

In conclusion, considerable scope for near field exploration is present in the Sable Sub-basin in conventional plays that have not been extensively explored since 1985.
Peripheral Vascular Dysfunction in Chronic Kidney Disease
Authors: Martens Christopher R. , Edwards David G.
Published: May 2011

There is an increased prevalence of cardiovascular disease- (CVD-) related mortality in patients with chronic kidney disease (CKD). Endothelial dysfunction is a primary event in the development of atherosclerosis and hypertension and likely contributes to the elevated cardiovascular risk in CKD. Endothelial dysfunction has been shown to occur in the peripheral vasculature of patients with both severe and moderate CKD. Mechanisms include oxidative stress, L-arginine deficiency, and elevated plasma levels of ADMA. Interventions designed to restore vascular function in patients with CKD have shown mixed results. Evidence from cell culture studies suggest that the accumulation of uremic toxins inhibits L-arginine transport and reduces nitric oxide production. The results of these studies suggest that endothelial dysfunction may become less reversible with advancing kidney disease. The purpose of this paper is to present the current literature pertaining to potential mechanisms of peripheral vascular dysfunction in chronic kidney disease and to identify possible targets for treatment.
Formate Formation and Formate Conversion in Biological Fuels Production
Authors: Crable Bryan R. , Plugge Caroline M. , McInerney Michael J. , Stams Alfons J. M.
Published: May 2011

Biomethanation is a mature technology for fuel production. Fourth
generation biofuels research will focus on sequestering CO2 and providing carbon-neutral or carbon-negative strategies to cope with dwindling fossil fuel supplies and environmental impact. Formate is an important intermediate in the methanogenic breakdown of complex organic material and serves as an important precursor for biological fuels production in the form of methane, hydrogen, and potentially methanol. Formate is produced by either CoA-dependent cleavage of pyruvate or enzymatic reduction of CO2 in an NADH- or ferredoxin-dependent manner. Formate is consumed through oxidation to CO2 and H2 or can be further reduced via the Wood-Ljungdahl pathway for carbon fixation or industrially for the production of methanol. Here, we review the enzymes involved in the interconversion of formate and discuss potential applications for biofuels production.
The relationship between 0.25–2.5 μm aerosol and CO2 emissions over a city
Authors: Vogt M. , Nilsson E. D. , Ahlm L. , Mårtensson E. M. , Johansson C.
Published: May 2011

Abstract. Unlike exhaust emissions, non-exhaust traffic emissions are completely unregulated and in addition, there are large uncertainties in the non-exhaust emission factors required to estimate the emissions of these aerosols. This study provides the first published results of direct measurements of size resolved emission factors for particles in the size range 0.25–2.5 μm using a new approach to derive aerosol emission factors based on carbon dioxide (CO2) emission fluxes. Aerosol fluxes were measured over one year using the eddy covariance method at the top of a 105 m high communication tower in Stockholm, Sweden. Maximum CO2 and particle fluxes were found when the wind direction coincided with the area of densest traffic within the footprint area. Negative fluxes (uptake of CO2 and deposition of particles) coincided with periods of sampling from an urban forest area. The fluxes of CO2 were used to obtain emission factors for particles by assuming that the CO2 fluxes could be directly related to the amount of fuel burnt by vehicles in the footprint area. The estimated emission factor for the fleet mix in the measurement area was, in number 1.8 × 1011 particle veh−1 km−1 (for 0.25–2.5 μm size range). Assuming spherical particles of density 1600 kg m−3 this corresponds to 27.5 mg veh−1 km−1. For particles (0.8–2.5 μm) the emission factors were 5.1 × 109 veh−1 km−1 for number and 11.5 mg veh−1 km−1 for mass. But a wind speed dependence was noted for high wind speeds. Thus, for wind speeds larger than 9 m s−1, as measured in the tower at 105 m (U105), the emission factor for particle number and mass was parameterised as: Ef (Number, 0.8–2.5 μm) = (6.1 ± 1.7)109 U105 −50 ± 188 and Ef (Mass, 0.8–2.5 μm) = (20 ± 12) U105 − 171 ±122.
A five year record of high-frequency in situ measurements of non-methane hydrocarbons at Mace Head, Ireland
Authors: Grant A. , Yates E. L. , Simmonds P. G. , Derwent R. G. , Manning A. J. , Young D. , Shallcross D. E. , O'Doherty S.
Published: May 2011

Abstract. Continuous high-frequency in situ measurements of a range of non-methane hydrocarbons have been made at Mace Head since January 2005. Mace Head is a background Northern Hemispheric site situated on the eastern edge of the Atlantic. Five year measurements (2005–2009) of six C2–C5 non-methane hydrocarbons have been separated into baseline Northern Hemispheric and European polluted air masses, among other sectors. Seasonal cycles in baseline Northern Hemispheric air masses and European polluted air masses arriving at Mace Head have been studied. Baseline air masses show a broad summer minima between June and September for shorter lived species, longer lived species show summer minima in July/August. All species displayed a winter maxima in February. European air masses showed baseline elevated mole fractions for all non-methane hydrocarbons. Largest elevations (of up to 360 ppt for ethane maxima) from baseline data were observed in winter maxima, with smaller elevations observed during the summer. Analysis of temporal trends using the Mann-Kendall test showed small (<6 % yr−1) but statistically significant decreases in the butanes and i-pentane between 2005 and 2009 in European air. No significant trends were found for any species in baseline air.
Numerical simulation and decomposition of kinetic energies in the Central Mediterranean Sea: insight on mesoscale circulation and energy conversion
Authors: Sorgente R. , Olita A. , Oddo P. , Fazioli L. , Ribotti A.
Published: May 2011

Abstract. The spatial and temporal variability of eddy and mean kinetic energy of the Central Mediterranean Sea has been investigated, from January 2008 to December 2010, by mean of a numerical simulation mainly to quantify the mesoscale dynamics and their relationships with physical forcing. In order to understand the energy redistribution processes, the baroclinic energy conversion has been analysed, suggesting hypotheses about the drivers of the mesoscale activity in this area. The ocean model used is based on the Princeton Ocean Model implemented at 1/32° horizontal resolution. Surface momentum and buoyancy fluxes are interactively computed by mean of standard bulk formulae using predicted model Sea Surface Temperature and atmospheric variables provided by the European Centre for Medium Range Weather Forecast operational analyses. At its lateral boundaries the model is one-way nested within the Mediterranean Forecasting System operational products. The model domain has been subdivided in four sub-regions: Sardinia channel and southern Tyrrhenian Sea, Sicily channel, eastern Tunisian shelf and Libyan Sea. Temporal evolution of eddy and mean kinetic energy has been analysed, on each of the four sub-regions composing the model domain, showing different behaviours. On annual scales and within the first 5 m depth, the eddy kinetic energy represents approximately the 60 % of the total kinetic energy over the whole domain, confirming the strong mesoscale nature of the surface current flows in this area. The analyses show that the model well reproduces the path and the temporal behaviour of the main known sub-basin circulation features. New mesoscale structures have been also identified, from numerical results and direct observations, for the first time as the Pantelleria Vortex and the Medina Gyre. The classical the kinetic energy decomposition (eddy and mean) allowed to depict and to quantify the stable and fluctuating parts of the circulation in the region, and to differentiate the four sub-regions as function of relative and absolute strength of the mesoscale activity. Furthermore the Baroclinic Energy Conversion term shows that in the Sardinia Channel the mesoscale activity, due to baroclinic instabilities, is significantly larger than in the other sub-regions, while a negative sign of the energy conversion, meaning a transfer of energy from the Eddy Kinetic Energy to the Eddy Available Potential Energy, has been recorded only for the surface layers of the Sicily Channel during summer.
A Pilot Investigation of Speech Sound Disorder Intervention Delivered by Telehealth to School-Age Children
Authors: Grogan-Johnson Sue , Gabel Rodney M. , Taylor Jacquelyn , Rowan Lynne E. , Alvares Robin , Schenker Jason
Published: May 2011

This article describes a school-based telehealth service delivery model and reports outcomes made by school-age students with speech sound disorders in a rural Ohio school district. Speech therapy using computer-based speech sound intervention materials was provided either by live interactive videoconferencing (telehealth), or conventional side-by-side intervention.  Progress was measured using pre- and post-intervention scores on the Goldman Fristoe Test of Articulation-2 (Goldman & Fristoe, 2002). Students in both service delivery models made significant improvements in speech sound production, with students in the telehealth condition demonstrating greater mastery of their Individual Education Plan (IEP) goals. Live interactive videoconferencing thus appears to be a viable method for delivering intervention for speech sound disorders to children in a rural, public school setting. Keywords:  Telehealth, telerehabilitation, videoconferencing, speech sound disorder, speech therapy, speech-language pathology; E-Helper
Copper‐Based Nanostructured Coatings on Natural Cellulose: Nanocomposites Exhibiting Rapid and Efficient Inhibition of a Multi‐Drug Resistant Wound Pathogen, A. baumannii, and Mammalian Cell Biocompatibility In Vitro
Authors: Cady Nathaniel C. , Behnke Jason L. , Strickland Aaron D.
Published: May 2011

This paper describes a layer‐by‐layer (LBL) electrostatic self‐assembly process for fabricating highly efficient antimicrobial nanocoatings on a natural cellulose substrate. The composite materials comprise a chemically modified cotton substrate and a layer of sub‐5 nm copper‐based nanoparticles. The LBL process involves a chemical preconditioning step to impart high negative surface charge on the cotton substrate for chelation controlled binding of cupric ions (Cu2+), followed by chemical reduction to yield nanostructured coatings on cotton fibers. These model wound dressings exhibit rapid and efficient killing of a multidrug resistant bacterial wound pathogen, A. baumannii, where an 8‐log reduction in bacterial growth can be achieved in as little as 10 min of contact. Comparative silver‐based nanocoated wound dressings–a more conventional antimicrobial composite material–exhibit much lower antimicrobial efficiencies; a 5‐log reduction in A. baumannii growth is possible after 24 h exposure times to silver nanoparticle‐coated cotton substrates. The copper nanoparticle–cotton composites described herein also resist leaching of copper species in the presence of buffer, and exhibit an order of magnitude higher killing efficiency using 20 times less total metal when compared to tests using soluble Cu2+. Together these data suggest that copper‐based nanoparticle‐coated cotton materials have facile antimicrobial properties in the presence of A. baumannii through a process that may be associated with contact killing, and not simply due to enhanced release of metal ion. The biocompatibility of these copper‐cotton composites toward embryonic fibroblast stem cells in vitro suggests their potential as a new paradigm in metal‐based wound care and combating pathogenic bacterial infections.
Single‐Electron Tunneling through Molecular Quantum Dots in a Metal‐Insulator‐Semiconductor Structure
Authors: Hayakawa Ryoma , Hiroshiba Nobuya , Chikyow Toyohiro , Wakayama Yutaka
Published: May 2011

A sigle‐electron tunneling (SET) in a metal‐insulator‐semiconductor (MIS) structure is demonstrated, in which C60 and copper phthalocyanine (CuPc) molecules are embedded as quantum dots in the insulator layer. The SET is found to originate from resonant tunneling via the energy levels of the embedded molecules, (e.g., the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO)). These findings show that the threshold voltages for SET are tunable according to the energy levels of the molecules. Furthermore, SET is observable even near room temperature. The results suggest, together with the fact that these properties are demonstrated in a practical device configuration, that the integration of molecular dots into the Si‐MIS structure has considerable potential for achieving novel SET devices. Moreover, the attempt allows large‐scale integration of individual molecular functionalities.
Degradation Effects Related to the Hole Transport Layer in Organic Solar Cells
Authors: Ecker Bernhard , Nolasco Jairo Cesar , Pallarés Josep , Marsal Lluis Francesc , Posdorfer Jörg , Parisi Jürgen , von Hauff Elizabeth
Published: May 2011

The influence of the hole transport layer on device stability in polymer:fullerene bulk‐heterojunction solar cells is reported. Three different hole transport layers varying in composition, dispersion solvent, electrical conductivity, and work function were used in these studies. Two water‐based hole transport layers, poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) and polyaniline:poly(styrene sulfonate), and one isopropyl alcohol‐based polyaniline:poly(styrene sulfonate) transport layer were investigated. Solar cells with the different hole transport layers were fabricated and degraded under illumination. Current–voltage, capacitance–voltage, and capacitance–frequency data were collected at light intensities of 16, 30, 48, 80, and 100 mW cm−2 over a period of 7 h. Device performance and stability were compared between nonencapsulated and encapsulated samples to gain understanding about degradation effects related to oxygen and water as well as degradation mechanisms related to the intrinsic instability of the solar cell materials and interfaces. It is demonstrated that the properties of the hole transport layer can have a significant impact on the stability of organic solar cells.
Nonlinear adaptive learning control for unknown time‐varying parameters and unknown time‐varying delays
Authors: Chen Weisheng , Zhang Zhengqiang
Published: May 2011

A new adaptive learning control approach is proposed for a class of first‐order nonlinear systems with two unknown time‐varying parameters and an unknown time‐varying delay. By reconstructing the system equation, all unknown time‐varying terms, including the time‐varying delay, are combined into an unknown periodic time‐varying vector, which is estimated by a periodic adaptive mechanism. By constructing a Lyapunov–Krasovskii‐like composite energy function (CEF), we prove the boundedness of all signals and the convergence of the tracking error. The results are extended to two classes of high‐order nonlinear systems with mixed parameters. Three simulation examples are provided to illustrate the effectiveness of the control algorithms proposed in this paper.

Copyright © 2011 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Gold nanoparticles‐based fluorescence enhancement of the terbium–levofloxacin system and its application in pharmaceutical preparations
Authors: Lee Sang Hak , Wabaidur Saikh Mohammad , Alothman Zeid Abdullah , Alam Seikh Mafiz
Published: May 2011

A sensitive fluorescence (FL) technique is proposed for the determination of levofloxacin (LVX). The method is based on the fact that the weak FL signal of the Tb(III)–LVX system is strongly enhanced in the presence of gold nanoparticles. Gold nanoparticles were prepared by the citrate reduction of HAuCl4 and characterized by transmission electron microscopy (TEM). Levofloxacin and Tb(III) ion form a fluorescence complex in aqueous solution, and its maximum emission wavelength was found at 545 nm. Optimal conditions for the formation of the levofloxacin–Tb(III) complexes were studied. Levofloxacin was detected by measuring the FL intensity, which increases linearly with the concentration of LVX in the range 6.2 × 10−10–2.6 × 10−8 mol/L. Recovery of the target analytes was > 96% with good quality parameters: linearity (r2 > 0.996), limit of detection (LOD) and limit of quantification (LOQ) values 2.1 × 10−10 mol/L and 7.2 × 10−10 mol/L, and run‐to‐run and day‐to‐day precisions with relative standard deviations (RSDs) around 3%. Thus, the proposed method can be successfully applied to the routine determination of levofloxacin in pharmaceutical preparations. Copyright © 2011 John Wiley & Sons, Ltd.
Abdominal organ donation after death
Authors: Roberts K J , Muiesan P
Published: May 2011

New approaches to increase donor organ supply
A New Approach to Construct a Doubly Interpenetrated Microporous Metal–Organic Framework of Primitive Cubic Net for Highly Selective Sorption of Small Hydrocarbon Molecules
Authors: Das Madhab C. , Xu Hui , Xiang Shengchang , Zhang Zhangjing , Arman Hadi D. , Qian Guodong , Chen Banglin
Published: May 2011

A new approach has been realized to construct a three‐dimensional doubly interpenetrated cubic metal–organic framework Zn2(PBA)2(BDC)⋅(DMF)3(H2O)4 (UTSA‐36, HPBA=4‐(4‐pyridyl) benzoic acid, H2BDC=1,4‐benzenedicarboxylic acid) through the self‐assembly of the pyridylcarboxylate linker 4‐(4‐pyridyl) benzoate and bicarboxylate linker 1,4‐benzenedicarxylate with paddle‐wheel [Zn2(COO)4]. The activated UTSA‐36 a exhibits highly selective gas sorption of C2H6, C2H4 and C2H2 over CH4 with the Henry law’s selectivities of 11 to 25 in the temperature range of 273 to 296 K attributed to the unique 3D intersected pore structure of about 3.1 to 4.8 Å within the framework, indicating that UTSA‐36 a is a potentially very useful and promising microporous material for such industrially important separation of C2 hydrocarbons over methane.
Design and implementation of an adaptive job allocation strategy for heterogeneous multi‐cluster computing systems
Authors: Yang Chao‐Tung , Chou Keng‐Yi , Lai Kuan‐Chou
Published: May 2011

Cluster computing is an attractive approach to provide high‐performance computing for solving large‐scale applications. Owing to the advances in processor and networking technology, expanding clusters have resulted in the system heterogeneity; thus, it is crucial to dispatch jobs to heterogeneous computing resources for better resource utilization. In this paper, we propose a new job allocation system for heterogeneous multi‐cluster environments named the Adaptive Job Allocation Strategy (AJAS), in which a self‐scheduling scheme is applied in the scheduler to dispatch jobs to the most appropriate computing resources. Our strategy focuses on increasing resource utility by dispatching jobs to computing nodes with similar performance capacities. By doing so, execution times among all nodes can be equalized. The experimental results show that AJAS can improve the system performance. Copyright © 2011 John Wiley & Sons, Ltd.
Low power Wallace multiplier design based on wide counters
Authors: Abed Sa'ed , Mohd Bassam Jamil , Al‐bayati Zaid , Alouneh Sahel
Published: May 2011

Multiplication is one of the most basic arithmetic operations. It is used in digital applications, central processing units, and digital signal processors. In most systems, the multiplier lies within the critical path and hence, due to probability and reliability issues, the power consumption of the multiplier has become very important. Moreover, as chips shrink and their power densities increase, power is becoming a major concern for chip designers. The ever increasing demand for portable applications with their limited battery lifetime indicates that power considerations should be a center stone in today's designs and the future's designs. Thus, all this has motivated us to provide a novel circuit design technique for a low power multiplier without compromising the multiplier's speed.

This paper presents a new power aware multiplier design based on Wallace tree structure. A new algorithm is proposed using high‐order counters to meet the power constraints imposed by mobility and shrinking technology. Commonly used multipliers of widths 8, 16, and 32 bits are designed based on the proposed algorithm. The new approach has succeeded in reducing the total number of gates used in the multiplier tree. Simulations on Altera's Quartus‐II FPGA simulator showed that the design achieves an average of 18.6% power reduction compared to the original Wallace tree. The design performs even better as the multiplier's size increases, achieving a 5% gate count reduction, a 26.5% power reduction, and a 23.9% better power‐delay product in 32‐bit multipliers. Copyright © 2011 John Wiley & Sons, Ltd.
Solution Chemistry Synthesis of Intermetallic Gold–Lithium Nanoparticles
Authors: Bondi James F. , Schaak Raymond E.
Published: May 2011

Colloidal nanoparticles of a prototype polar intermetallic compound, Au3Li, were synthesized by reacting Au nanoparticle seeds with n‐butyllithium. X‐ray and electron diffraction data are consistent with the L12 (Cu3Au) structure type expected for Au3Li. Composition analysis indicates a stoichiometry of approximately Au3Li0.7, which is within the reported composition range of the Au3Li phase. The Au3Li nanoparticles decompose in water to regenerate Au. The successful synthesis of Au3Li as colloidal nanoparticles demonstrates that polar intermetallic compounds containing highly electropositive elements are accessible by using low‐temperature solution chemistry routes and that they are also amenable to nanostructuring.