bluuebunny/crossref_metadata_2025 huggingface dataset:
Is it necessary to resolve the Debye length in standard or
δ
f PIC codes?
Authors: McMillan B. F.
Published: May 2020

Numerical instabilities of standard Particle-In-Cell (PIC) codes were observed and explained very early in their development. In the zero-time step limit, these instabilities arise from the interaction between the spatial grid and the (artificial) particle shape functions. δf PIC codes, which have recently been especially popular in gyrokinetic simulations, suffer from similar instabilities. In the zero time step limit, the numerical stabilities of standard and δf methods are equivalent. Numerical instabilities arise when the simulation grid does not “resolve the Debye length,” but many modern PIC codes use relatively high order shape functions, and as a result, the worst-case numerical growth rates are undetectably small; in addition, some codes use energy-conserving methods which usually prevent this numerical instability from arising. Similarly, a numerical instability was found in a gyrokinetic δf code using a first-order shape function; we show that this is related to the usual PIC numerical instability. In the gyrokinetic case, where waves have acoustic dispersion at a large wavenumber, increasing the grid resolution actually increases the growth rate of the numerical instability, and the prescription of resolving an effective Debye length is not applicable. However, using higher order shape functions is still an effective remedy.
Optothermally induced mechanical oscillation in a silk fibroin coated high-Q microsphere
Authors: Liu Yiming , Jiang Xuefeng , Wang Changqing , Yang Lan
Published: May 2020

Protein-based optical devices with biocompatibility and biodegradability have distinct advantages for applications in biomedical sensing. Silk fibroin with unique optical, thermal, and mechanical properties renders great flexibility in designing functional photonic platforms. Here, we report the experimental observation of optothermally induced mechanical oscillation in a silk-fibroin coated microcavity. Theoretical analysis reveals that the observed oscillation results from the interplay of several nonlinear effects in the silk-coated-microsphere as well as the coexistence of fast and slow thermal dynamic processes. The physics in our study breaks ground for the study of nonlinear dynamics of structural protein optical material that can be used for functional optical devices.
Jumping droplets electronics cooling: Promise versus reality
Authors: Foulkes Thomas , Oh Junho , Sokalski Peter , Li Longnan , Sett Soumyadip , Sotelo Jesus , Yan Xiao , Pilawa-Podgurski Robert , Castaneda Adam , Steinlauf Matthew , Miljkovic Nenad
Published: May 2020

Electrifying both stationary and mobile systems requires ultra-compact, lightweight power electronics and electric machines. Increasing the volumetric and gravimetric density of these systems is constrained, however, by the capacity to remove heat from these assemblies. A promising method for extracting heat is jumping droplet condensation, which can address both spatially and temporally changing hotspots. Yet, disagreement exists in the literature about the maximum attainable heat flux for water-based, droplet jumping devices such as vapor chambers, with values ranging from 5 to 500 W/cm2. Here, using thermal measurements and optical imaging in pure vapor conditions, we directly observe the hydrodynamics occurring inside of a jumping droplet vapor chamber. Our experiments show that flooding is the key obstacle limiting jumping droplet mass flux to hot spots, limiting heat transfer to less than 15 W/cm2. These results indicate that past works reporting high heat fluxes benefited from other hot spot cooling pathways such as previously observed liquid bridges formed due to flooding. To test our hypothesis, we characterize progressive flooding on a variety of structured surfaces ranging in length-scale from 100 nm to 10 μm. Progressive flooding was delayed by decreasing the length-scale of the surface structures, which supports recent observations in the literature. Our work not only helps to understand the wide variability of past results quantifying droplet jumping heat transfer, but also provides design guidelines for the development of surfaces that are capable of maintaining enhanced jumping droplet condensation.
Electronic structure of epitaxial perovskite films in the two-dimensional limit: Role of the surface termination
Authors: Schütz P. , Kamp M. , Di Sante D. , Lubk A. , Büchner B. , Sangiovanni G. , Sing M. , Claessen R.
Published: May 2020

An often-overlooked property of transition metal oxide thin films is their microscopic surface structure and its effect on the electronic properties in the ultrathin limit. Contrary to the expected conservation of the perovskite stacking order in the (001) direction, heteroepitaxially grown SrIrO3 films on TiO2-terminated SrTiO3 are found to exhibit a terminating SrO surface layer. The proposed mechanism for the self-organized conversion involves the adsorption of excess oxygen ions at the apical sites of the IrO2-terminated surface and the subsequent decomposition of the IrO6 octahedra into gaseous molecular IrO3 and the remaining SrO-terminated surface. Whereas the ab initio calculated electronic structure of SrO-terminated SrIrO3 in the monolayer limit exhibits a striking similarity to bulk Sr2IrO4, the broken octahedral symmetry at the IrO2-terminated surface would mix the otherwise crystal field split eg and t2g states, resulting in distinctly different low-energy electronic states.
Metalorganic chemical vapor phase deposition of AlScN/GaN heterostructures
Authors: Ligl Jana , Leone Stefano , Manz Christian , Kirste Lutz , Doering Philipp , Fuchs Theodor , Prescher Mario , Ambacher Oliver
Published: May 2020

AlScN/GaN heterostructures are worth investigating due to the remarkable high gradients in spontaneous polarization at their interfaces, which brings them into play for a wide field of potential high-power and high-frequency electronic applications. In this work, AlScN/GaN heterostructures for high electron mobility transistor (HEMT) structures were grown by metalorganic chemical vapor deposition. We have investigated the impact of growth parameters on thick AlScN layers and on thin AlScN/GaN heterostructures. Growth parameters, such as temperature, V/III ratio, pressure, and growth mode, were varied with the focus on surface morphology, crystal quality, and incorporation of impurities. High growth temperatures improve the surface quality and reduce impurities incorporation notably. In addition to that, a slight decrease in carbon concentration is obtained by adopting a pulsed supply of metalorganic precursors. V/III ratio and pressure did not influence the layer quality observably. Heterostructures with root mean square surface roughness values as low as 0.38 nm, revealing smooth growth steps, were achieved. The presence of two-dimensional electron gases with sheet carrier densities and mobilities of up to 2 × 1013 cm−2 and close to 900 cm2/(V s), respectively, resulted in channel sheet resistances as low as 337 Ω/sq, very suitable for AlScN/GaN HEMTs. Heterostructures with sheet resistances below 200 Ω/sq and sheet carrier densities of 5 × 1013 cm−2 were also achieved but showed significantly lower mobility.
The influence of magnetic field curvature on intermittency in drift-wave turbulence in the stellarator TJ-K
Authors: Garland S. , Manz P. , Ramisch M.
Published: May 2020

The influence of magnetic field curvature on the intermittency in density and potential fluctuations in drift-wave turbulence has been investigated in the stellarator TJ-K in the framework of an extended Hasegawa–Wakatani model. A structure function analysis was used to estimate the intermittency level of poloidally resolved drift-wave turbulence measurements of a deuterium plasma in TJ-K. Potential fluctuations were found to be broadly self-similar, whereas density fluctuations were found to be more intermittent in the region with negative normal and positive geodesic curvatures. This behavior could be understood by comparing the data to two-dimensional extended Hasegawa–Wakatani simulations that retain gradients in the magnetic field strength, giving rise to curvature effects. The model is able to reproduce the trends in the experimental data if both normal and geodesic curvature effects are accounted for, as well as the local anisotropy of turbulent length scales. The analysis indicates the importance of local magnetic geometry as a factor in the decoupling of density and potential fluctuations, leading to intermittency in drift-wave turbulence.
Tunable magnetic properties in van der Waals crystals (Fe1−xCox)5GeTe2
Authors: Tian Congkuan , Pan Feihao , Xu Sheng , Ai Kun , Xia Tianlong , Cheng Peng
Published: May 2020

We report the doping effects of cobalt on van der Waals (vdW) magnet Fe5GeTe2. A series of (Fe1−xCox)5GeTe2 (0 ≤ x ≤ 0.44) single crystals have been grown, and their structural, magnetic, and transport properties are investigated. For x = 0.20, the Curie temperature TC increases from 276 K to 337 K. Moreover, the magnetic easy axis is reoriented to the ab-plane from the c-axis in undoped Fe5GeTe2 with largely enhanced magnetic anisotropy. A complex magnetic phase diagram is identified on the higher doping side. The x = 0.44 crystal first orders ferromagnetically at TC = 363 K and then undergoes an antiferromagnetic (AFM) transition at TN = 335 K. Furthermore, magnetic-field-induced spin-flop transitions are observed for the AFM ground state. Our work reveals (Fe1−xCox)5GeTe2 as promising candidates for developing spin-related applications and proposes a method to engineer the magnetic properties of the vdW magnet.
Thermal conductivity reduction by scallop shaped surface modulation in silicon nanowires
Authors: Lee Seungho , Yoo Hyeongseok , Won Woo-Yeon , Cho Hyeonsu , Seo Myunghae , Kong Byoung Don , Meyyappan M. , Baek Chang-Ki
Published: May 2020

We report the reduction of thermal conductivity and phonon mean-free-path below the Casimir limit originated by phonon backscattering in silicon nanowires with scallop shaped surface modulation. The scallop surface modulation with a period of 55–110 nm on 200 nm diameter nanowires was created using top-down deep-reactive-ion-etching. The measured thermal conductivity was 15.13 W m−1 K−1, 34% lower than those of nanowires fabricated by metal-assisted-chemical-etching with a similar diameter, and 60% lower than the Casimir limit. An analysis using the phonon Boltzmann transport equation and radiation analogy of ballistic phonons shows that this drastic reduction stems from the phonon backscattering at the scallop surface. The thermal conductivity measured at 300–500 K showed a nearly temperature-independent trend suggesting that the structural control can overcome a material limit. Our results provide a systematic nanostructure control approach to improve the thermoelectric efficiency more than the limit imposed by a material.
Narrow linewidth characteristics of interband cascade lasers
Authors: Deng Yu , Zhao Bin-Bin , Wang Xing-Guang , Wang Cheng
Published: May 2020

Narrow-linewidth mid-infrared laser sources are highly demanding for high-resolution gas spectroscopy applications. Interband cascade lasers (ICLs) are power-efficient laser sources emitting in the mid-infrared range. This work unveils the low phase noise characteristics of distributed feedback ICLs driven by a battery source. We show that the measured spectral linewidth of ICLs is as narrow as 284 kHz (at a 1 ms observation time), which is smaller than those of common quantum cascade lasers. On the other hand, raising the pump current reduces the intrinsic linewidth down to 12 kHz. The linewidth broadening factor is in the range of 2.0–3.0, leading to a Schawlow–Townes linewidth as narrow as 1.6 kHz. This work suggests the high potential of developing battery-driven, high-resolution gas spectroscopy instruments using ICLs.
Large anisotropic magnetocaloric effect in ferromagnetic semimetal PrAlSi
Authors: Lyu Meng , Wang Zhen , Ramesh Kumar K. , Zhao Hengcan , Xiang Junsen , Sun Peijie
Published: May 2020

We report on the large anisotropic magnetocaloric effect of PrAlSi, a ferromagnetic semimetal of current interest with a probable topologically nontrivial electronic structure. The maximum magnetic entropy change amounts to −ΔSM=22.6J/kgK near the Curie temperature TC=17.8K under a magnetic field change of μ0ΔH=5T along the magnetic easy c axis. A highly relevant feature is the small crystalline electric field splitting of the Pr3+ (J=4) multiplet, which appears to be comparable with the effective exchange interaction in the magnetic ordering. This leads to the full saturation moment of the Pr3+ ion in small fields and an accumulation of magnetic entropy in the vicinity of the magnetic ordering. The weakly first-order nature of the ferromagnetic transition and the subsequent reentrant spin-glass transitions below TC are features further enhancing the magnetocaloric effect. Given the strong magnetic anisotropy, a large rotating magnetocaloric effect becomes achievable in this material.
In situ growth of B4C nanowires on activated carbon felt to improve microwave absorption performance
Authors: Wang Beibei , Fu Qiangang , Song Qiang , Yu Zhaoju , Riedel Ralf
Published: May 2020

Boron carbide (B4C) nanowires were synthesized on the surface of activated carbon felt (ACF) via an in situ thermal growth method. The microstructures of B4C nanowires were characterized by field emission scanning electron microscopy, transmission electron microscopy, and x-ray diffraction. The minimum reflection loss (RLmin) value of 40 wt. % ACF@B4C hybrid materials amounts to −36.1 dB at 17.2 GHz and the effective absorption bandwidth (RL < −10 dB) is obtained over a high frequency range of 15.9–18 GHz with an absorber layer thickness of 5 mm. The obtained results prove that ACF@B4C hybrid materials have high potential as microwave absorbers with excellent microwave absorption property.
Molecular heterogeneity in aqueous cosolvent systems
Authors: Oh Kwang-Im , Baiz Carlos R.
Published: May 2020

Aqueous cosolvent systems (ACoSs) are mixtures of small polar molecules such as amides, alcohols, dimethyl sulfoxide, or ions in water. These liquids have been the focus of fundamental studies due to their complex intermolecular interactions as well as their broad applications in chemistry, medicine, and materials science. ACoSs are fully miscible at the macroscopic level but exhibit nanometer-scale spatial heterogeneity. ACoSs have recently received renewed attention within the chemical physics community as model systems to explore the relationship between intermolecular interactions and microscopic liquid–liquid phase separation. In this perspective, we provide an overview of ACoS spatial segregation, dynamic heterogeneity, and multiscale relaxation dynamics. We describe emerging approaches to characterize liquid microstructure, H-bond networks, and dynamics using modern experimental tools combined with molecular dynamics simulations and network-based analysis techniques.
Multifold coupling enabled high quality factor toroidal resonances in metasurfaces
Authors: Kumar Deepak , Ambatipudi Surya Pranav , Banerjee Sabyasachi , Kumar Ranjan , Roy Chowdhury Dibakar
Published: May 2020

The phenomena of toroidal resonances can lead to extraordinary strong confinement of electromagnetic energy inside a physical system. Very recently, toroidal resonances were observed in metamaterial systems too. Because of strong electromagnetic field confinements, associated radiative losses in toroidal modes can be tailored to extremely low values leading to simultaneous high quality (Q) factor and high figure of merit (FoM) resonances. Such metamaterial systems can be attractive for sensors, lasing spasers, nonlinear devices, narrow band filters, etc. However, demonstrating toroidal modes with high Q factors is a challenging task in a typical metamaterial system. In this work, we have experimentally demonstrated a strategy for achieving toroidal resonances with high Q factor and FoM in single resonator based planar metamaterials. At resonance, magnetic dipoles akin to toroidal topology are excited in these structures. The anti-aligned circulating surface currents are observed along the circumference of metal split rings which resulted in a head to tail arrangement of the magnetic dipoles across the unit cells. We attribute the observation of high-quality factor toroidal modes to the strong inter-unit cell near field coupling of the induced magnetic field lines. Such multifold toroidal mode leads to resonances with exceptionally high quality factors because of significant reduction in radiation losses. Our experiments demonstrate Q factor and FoM of 183 and 76, respectively, making these metasurfaces a strong candidate for practical applications where high Q resonances are crucial.
Comprehensive basin-wide 3D petroleum systems modelling providing new insights into proven petroleum systems and remaining prospectivity in the Exmouth Sub-basin, Australia
Authors: Schenk Oliver , Dempsey Craig , Benson Robbie , Cheng Michael , Tewari Sugandha , Karvelas Alex , Bancalà Giuseppe
Published: May 2020

The Exmouth Sub-basin is part of the Northern Carnarvon Basin, offshore north-west Australia, and has undergone a complex tectonic history. Hydrocarbon exploration resulted in the discovery of a variety of oil and gas accumulations; however, their distribution and charge history from different petroleum systems is still poorly understood due to limited knowledge of the deeper basin architecture. The basin-wide, long-offset, broadband 2017 Exmouth 3D multiclient seismic dataset allowed a seamless interpretation into this deeper section. This work revealed new insights on the tectono-stratigraphic evolution of the Exmouth Sub-basin. Mesozoic extension, that was restricted to the latest Triassic, was followed by a sag phase with homogeneous, shale-dominated deposition, resulting in source rock potential for the entire Jurassic section. These findings, together with potential field modelling, were integrated into this first basin-wide 3D petroleum system model to better constrain the thermal history and petroleum systems. The model improved our understanding of the complex charge history of hydrocarbon fields. It predicts that hydrocarbon expulsion from Late Jurassic source rocks continued into the Late Cretaceous, a period when the regional Early Cretaceous Muderong Formation was an efficient seal rock. This implies that, in addition to long-distance, sub-Muderong migration, vertical, short-distance migration may have contributed significant petroleum charge to the discovered accumulations in the southern Exmouth Sub-basin. The model also predicts additional prospective areas: fault-seal structures within Early Cretaceous intervals north of the Novara Arch, intra-formational Late Jurassic sandstones north of the current fields (with low biodegradation risk) and Triassic reservoirs along the basin margins and north of the Jurassic depocentre.
Characterisation of Surat Basin Walloon interburden and overlying Springbok Sandstone: a focus on methane adsorption isotherms, permeability and gas content
Authors: Raza Syed Shabbar , Pearce Julie , Shukla Pradeep , Hayes Phil , Rudolph Victor
Published: May 2020

The Surat Basin in Queensland is one of the world’s premier producers of natural gas from coal seams. We investigate the potential for clay-rich Walloon Coal interburden and the overlying Springbok Sandstone to hold or produce gas. Seventeen core samples were analysed from two wells from intervals within the Walloon Upper Juandah Coal Measures interburden and the Springbok Sandstone. Samples were characterised using high-pressure methane adsorption isotherms, canister gas desorption tests, moisture contents, ash contents, carbon contents, scanning electron microscopy/energy dispersive X-ray spectrometry, X-ray quantitative clay analysis, permeability, helium pycnometry and mercury intrusion porosimetry. Methane adsorption was conducted at 30°C with up to 8 MPa pressure on dried crushed samples. The adsorption capacity of methane at 8 MPa varied from 3 cc/g (calcite-cemented) up to 25 cc/g (standard temperature and pressure equivalent) (coal). Clay-rich interburden samples adsorbed ~5–14 cc/g (dry). The measured isotherms and methane content from canister desorption tests show that appreciable volumes of gas are contained within some portions of interburden and in the overlying Springbok Sandstone. Gas within the interburden likely represents a large volumetric resource, albeit in low permeability rock that restricts direct productivity. The gas adsorption and gas content results for the Springbok Sandstone help to explain field observations of high gas content in some landholder water wells.
Real-time integrity monitoring for oil and gas assets
Authors: Putrino Michael A.
Published: May 2020

Integrating design and operating envelopes of an asset with live operations data allows operators to see exceedances in real time and precisely understand the health of their asset. This technology is a direct stem of the rapidly growing digitalisation philosophy of many operators, whereby data that have traditionally been locked in PDF documents, Excel spreadsheets and other silos can be digitised, structured and connected to many different end points. For asset integrity monitoring, this means digitising and integrating design envelopes, data historians, enterprise resource planning systems and calculation tools with a unified front-end visualisation, to display what is really happening on an asset. By integrating and visualising these data sources, it is possible to create a single location for monitoring the health of all operator assets and generating reports for continued assessment. Once established, the platform provides a base for deployment of other intelligent toolkits, such as pattern recognition for valve signature monitoring, or predictive modelling for corrosion management over the life of field. This extended abstract uses a case study to discuss the benefits of standardising the visualisation landscape for monitoring the health of assets, the improvements and efficiencies delivered to the integrity monitoring process, the ability to highlight flaws in the design envelopes, and the engineering required to ensure that the right instrument is monitoring the right equipment.
Dorado discovery – unlocking a major new oil and gas play in the Bedout Sub-basin
Authors: Thompson Melissa
Published: May 2020

In 2014, Santos (formerly Apache and Quadrant Energy Limited) acquired an operated exploration position over most of the under-explored Bedout Sub-basin. A multi-year exploration program was subsequently executed, targeting plays within Middle Triassic fluvio-deltaic sediments of the Lower Keraudren and Archer formations. Initial wells at Phoenix South and Roc established the presence of high-quality reservoirs, source rocks and hydrocarbon fluids, but the commerciality of these discoveries was impeded by the lack of existing production infrastructure in this frontier basin. In 2018, Santos and its Joint Venture partner, Carnarvon Petroleum, drilled Dorado-1, targeting stacked Archer Formation reservoirs in an erosional truncation trap set up by a major canyon system. The well encountered light oil and/or condensate rich gas in high-quality reservoir sands at each of the target intervals. Despite limited well control, burial depths on the order of 4000 m and imperfect seismic data, the pre-drill prognosis was remarkably accurate, largely due to the application of modern seismic inversion techniques. Subsequent appraisal drilling undertaken during 2019 demonstrated the discovery is larger than originally anticipated and has significantly de-risked a future development. New seismic acquired during 2019 will be used to further improve the understanding of Dorado reservoirs and to mature follow-up prospects for future drilling.
Technical de-risking of a demonstration CCUS project for final investment decision in Australia
Authors: Bagheri Mohammad , Pevzner Roman , Jenkins Charles , Raab Matthias , Barraclough Paul , Watson Max , Dance Tess
Published: May 2020

CO2CRC is developing subsurface monitoring technologies which can significantly reduce the cost and environmental footprint compared to traditional 4D surface seismic. These can be applicable to both hydrocarbon production and CO2 injection projects. These methodologies involve continuous seismic monitoring using well-based distributed acoustic sensors and pressure tomography. CO2CRC’s Otway Stage 3 Project is aiming to validate these techniques while injecting 15000 t of CO2 into the Paaratte Formation in the Otway basin and monitoring the plume using an array of six wells. The main technical risks for subsurface monitoring are migration of the plume outside of the survey area and lack of communication between the wells. Moreover, given some amount of CO2 is already in the injection formation (from CO2CRC Otway Stage 2C Project), it is required to understand the chance of the new plume merging with the existing plume and the possible timeframe. This paper summarises the workflow followed to de-risk the project and optimise the injection and monitoring wells location to reduce the abovementioned risk factors. As a result of the de-risking process, by changing different parameters and mitigating some of the risks, we gained a high degree of confidence that the CO2 plume will stay within the survey area and that the chance of pressure communication between the wells was increased. A thorough sensitivity analysis was also performed to understand the influence of each parameter on the plume speed. This process provided a higher confidence to decision makers to make a final AU$45 million investment decision.
The CarbonNet Project – a case study of the use of marine assessments and advisory panels for stakeholder assurance
Authors: Mendes Da Costa Victoria
Published: May 2020

The CarbonNet project is investigating the feasibility of commercial-scale carbon capture and storage in Victoria. CarbonNet has identified a prospective storage site called Pelican, in the offshore Gippsland Basin in Bass Strait. CarbonNet undertook a 3D marine seismic survey (MSS) in 2018 as part of the appraisal program for Pelican. Environmental impacts and risks associated with the MSS were assessed in an Environment Plan accepted by Commonwealth and Victorian regulators. Underwater sound and its impact on the marine environment was a key issue raised by stakeholders. In response, CarbonNet put several initiatives in place to address concerns, including: undertaking marine habitat assessments before and after the MSS; and establishing an independent advisory panel to provide advice on the marine habitat assessments. The objectives of the habitat assessments were to confirm the abundance of key marine species before and after the MSS, and to determine whether any differences could be attributed to the MSS. To ensure that the habitat assessments were undertaken in a scientifically robust manner, an advisory panel was established consisting of representatives from regulatory agencies, academia and the fishing industry. This paper provides an overview of how CarbonNet used marine assessments and an advisory panel for stakeholder assurance.
The impact of fly-in, fly-out (FIFO) on the health and well-being of employees: what organisations can do to mitigate the risks and improve outcomes
Authors: Brook Elizabeth , Freeman Melanie , Ditchburn Graeme
Published: May 2020

Concerns about the increased risk to mental health in fly-in, fly-out (FIFO) workers in the construction and resources industries led to increased public and government scrutiny, resulting in Western Australia’s adoption of a code of practice. In general, research has found that a higher incidence of psychological distress in FIFO workers has resulted from high compression rosters and work–family conflict, as well as feelings of isolation. Risk controls, such as perceived levels of support, have been found to be significantly related to improved mental health and organisational outcomes. Organisations need to address the non-financial needs of their workers and look to develop their perceived support, job satisfaction and adjustment to the FIFO lifestyle. This paper outlines practical risk controls and interventions organisations can take to improve psychological and organisational outcomes.
The impact of oil and gas infrastructure in marine ecosystems: a global vision for informing decommissioning decisions
Authors: McLean D. L. , Bond T. , Partridge J. C. , Rouse S. , Love M.
Published: May 2020

The offshore hydrocarbon basins of the world and their neighbouring countries are faced with an immense decommissioning challenge. Uncertainties in regulation and costs, coupled with limited environmental data, stifle consideration and support for alternative options to full removal. In separate regions, scientists and industry are forming partnerships and commencing research that advances understanding of regional and ecosystem-scale processes, including the habitat value of oil and gas infrastructure. With similar decommissioning-related marine research priorities being identified globally, a more coordinated approach to such research is needed: a global decommissioning marine research network and taskforce. This taskforce would not only be highly cost-effective, but it would also enable consistent approaches to science and management of the marine environment and secure protection and conservation of global marine resources. This network and taskforce would bring together leading scientists and experts in the oil and gas industry to develop an international research program that will significantly advance our understanding of the consequences to ecosystems as a result of decommissioning, as well as identify the differences and commonalities in environment–infrastructure interactions across different geographical regions. The outcomes would support sustainable installation and decommissioning practices worldwide and ensure that policies adhere to international agreements on environmental protection.
NORM inventory forecast for Australian offshore oil and gas decommissioned assets and radioactive waste disposal pathways
Authors: McKay Scott , Higgins Stuart A. , Baker Peter
Published: May 2020

This research establishes a decommissioning timeline for the existing oil and gas facilities across all of the Australian offshore oil and gas production basins. Minimal data exist in the public domain to estimate these decommissioning timelines and, more importantly, the significant waste volumes generated; including potentially hazardous wastes such as naturally occurring radioactive material (NORM). At this time there is no approved onshore radioactive waste disposal pathway in Australia to accommodate this material. Applying an estimation methodology, based on Norwegian decommissioning data with regional activity factors, allows a NORM waste forecast to be established for the decommissioning of Australian oil and gas offshore infrastructure. The total NORM disposal burden is estimated to be in the range of 223–1674 tonnes for decommissioning activity to 2060, with over 68% of this material generated between 2018 and 2025. Due to the sparsity of public domain data this forecast is deemed to be uncertain and excludes the NORM contamination anticipated to be present in subsea export pipelines, trunklines and well production tubing. Current regulations governing the categorisation and disposal of radioactive wastes across Australia are complex and regionally dependent. This regional variation makes the implementation of a national radioactive waste disposal facility more difficult, and encourages the export of radioactive wastes overseas for final disposal. Exporting of radioactive wastes potentially presents a higher risk compared with in-country disposal and is likely not an effective long-term proposition. A comprehensive NORM data collection and quantification assessment programme, spanning all onshore and offshore oil and gas infrastructure, needs to implemented to drive and verify a NORM waste management strategy for the wave of facility decommissioning projects that are fast approaching.
The prospectivity of the Late Triassic intervals in the outboard Exmouth Plateau, Western Australia
Authors: Paten Tom
Published: May 2020

The Exmouth Plateau is a deep-water plateau on the Australian continental margin underlain by 10–15 km of flat-lying, tilted and block-faulted Paleozoic–Mesozoic sedimentary rocks, which were deposited predominantly during periods of extension before continental break-up commenced in the middle Jurassic. The recent acquisition of the Mawson MC3D broadband seismic survey provides a modern, high-quality dataset located ~230 km to the north-west of Dampier, in the outboard Exmouth Plateau, in a relatively under-explored portion of the Northern Carnarvon Basin. The Late Triassic Mungaroo Formation is the primary reservoir target for the majority of the exploration in the Exmouth Plateau to date. A detailed investigation into the reservoir potential and prospectivity of the Mungaroo Formation is possible by utilising this modern dataset. The high-quality data presents a high-resolution view of the Rhaetian carbonate reef platforms and pinnacle reef complexes that are present within the Mawson survey footprint, revealing an under-explored play type within the region. The development of a detailed stratigraphic framework through the Late Triassic–Jurassic, combined with the use of attribute analyses and amplitude versus offset products can help de-risk identified prospects and highlight further prospectivity during the exploration process.
Putting safety leadership thinking into practice
Authors: Carvalho Mariana , Robinson Simon , Anderson Martin
Published: May 2020

The International Association of Oil & Gas Producers (IOGP) is a global forum in which member companies identify and share best practices to achieve improvements in many areas, including upstream safety. In 2013, IOGP published Report 452: Shaping safety culture through safety leadership. Written collaboratively by a team of industry experts, the principles of academic and theoretical work from authors such as Andrew Hopkins and James Reason were used to produce a short guide for industry leaders to explain how their leadership characteristics can shape the culture of their organisation. This report has been the most popular of the IOGP reports, with requests for over 1500 hard copies despite the report being publicly available to download at no cost. This level of industry interest prompted the authors to create a complimentary guidance document aimed at senior and middle management as well as supervisor levels to support their application of safety leadership characteristics in developing and maintaining a workplace culture with safety as a core value. The guidance uses the recent experiences of IOGP member companies in how a positive, safety-oriented organisational culture is formed and maintained. Using a straight-forward, storytelling approach, the reader is introduced to the theoretical concepts using practical workplace examples, aimed to resonate with the reader. This paper will provide a summary of the IOGP guidance as well as example good practice case studies from IOGP member companies.
Improving industry safety via real collaboration: a case study from the Qld CSG sector
Authors: Zaunbrecher Michelle L. , O’Donnell Sean
Published: May 2020

The Queensland (Qld) coal seam gas (CSG) sector grew quickly between 2009 and 2010. The industry was young, with many new and inexperienced workers, risk controls and systems were relatively immature and there was an overall nascent safety culture and poor safety performance. It was recognised that if there was to be real change made, two fundamental shifts were needed: (1) the contractor companies must be part of the change, because most of safety risk exposure hours for field operations were with the contractor workforce; and (2) the senior leadership of both the operating and contractor companies needed to form, own and steer a new safety mandate. In 2014, a workshop was run where the senior leaders of both the operator and contractor companies attended; as a direct result, the industry group of Safer Together was born. Since the formation of Safer Together, the broader benefits of collaboration are as follows: industry is connected via its safety performance and viewed as an entity; there have been real and demonstrable safety performance improvements; there has been a tangible positive shift in culture where good safety performance is a fundamental expectation; it is important for personnel, and new workers who may want to join the industry, to have a high level of confidence in the high standards of safety in the industry; positive communication and relationships with the regulators has enabled practical regulatory reform and approach to safety compliance; and a positive reputation on the industry’s ability to be safe provides an overall very positive contribution to the industry’s ‘licence to operate’. Effective collaboration across the industry on safety has not yet been fully met, and challenges remain. Despite these challenges, the Qld CSG industry has demonstrable safety improvements that can be tied directly to the benefits of positive industry collaboration on safety. The Qld CSG industry story of collaboration is built from the passion and contribution of many individuals. The real point is that so much more has been achieved with a common direction and purpose than any individual or single company could achieve.
Auto-control model building using machine learning regression for extreme response prediction
Authors: Leong Darrell , Bahuguni Anand
Published: May 2020

The long-term forecast of extreme response presents a daunting practical problem for offshore structures. These installations are subject to varying sea conditions, which amplify the need to account for the uncertainties of wave heights and periods across a given sea state. Analysis of each sea state involves numerically intensive non-linear dynamic analysis, leading to massive computational expense across the environmental scatter diagram. Recent research has proposed several effective solutions to predict long-term extreme responses, but not without drawbacks, such as the limitation to specific failure locations and the absence of error estimates. This paper explores the practical implementation of control variates as an efficiency enhancing post-processing technique. The model building framework exhibits the advantage of being fully defined from existing simulation results, without the need for external inputs to set up a control experiment. A composite machine learning regression model is developed and investigated for performance in correlating against Monte Carlo data. The sampling methodology presented possesses a crucial advantage of being independent of failure characteristics, allowing for the concurrent extreme response analyses of multiple components across the global structure without the need for re-analysis. The approach is applied on a simulated floating production storage and offloading unit in a site located in the hurricane-prone Gulf of Mexico, vulnerable to heavy-tailed extreme load events.
Suitability of litter amendments for the Australian chicken meat industry
Authors: Cockerill S. A. , Gerber P. F. , Walkden-Brown S. W. , Dunlop M. W.
Published: May 2020

The Australian chicken meat indutstry is rapidly expanding due to the increasing consumption of chicken meat. As a result, the industry has growing issues of sourcing new bedding materials and disposing of spent litter, which can be attributed, in part, to a lack of widespread litter re-use for rearing chickens. According to insights and perspectives recently gathered from industry stakeholders, it is believed that re-using litter will become more common in the future, so as to reduce production costs and ease pressures on both the supply of new bedding materials and disposal of spent litter. However, there are potential risks that need to be addressed if litter re-use increases, particularly with regard to the production and mitigation of ammonia, which can negatively affect chicken health if not managed correctly. The present review discusses the potential benefits reported for different types of litter amendments, which have the primary goal of reducing ammonia volatilisation, but may also contribute to improvements in bird performance, welfare, pathogen loads, fertiliser value of spent litter, and reduced costs associated with purchasing new bedding materials. Acidifiers have been shown to be the most effective of all amendment types, with sodium bisulfate or alum being among the most commonly tested products mentioned in research literature. Litter amendments are currently rarely used in Australia, but it is hoped that the information provided in the present review, based mostly on overseas usage and research, will help inform future decision-making on the use of these products in Australian poultry production systems.
Language Policy in Business
Authors: Barakos Elisabeth
Published: May 2020

Language Policy in Business: Discourse, ideology and practice provides a critical sociolinguistic and discursive understanding of language policy in a minority language context. Focusing on Welsh-English bilingualism in private sector businesses in Wales, the book unpacks the circulating discourses, ideologies and practices of promoting bilingualism as a sociocultural and economic resource in the globalised knowledge economy. It sheds light on businesses as ideological sites for struggles over language revitalisation, which has been characterised by tensions and discursive shifts from essentialist ideologies about language, identity, nation and territory, to an increased commodification of bilingualism.
The book is premised on the understanding that language is a focal point for articulating and living out historical power relationships and inequalities, and that language policy processes are never apolitical. It adds to a body of literature about bilingualism in minority language contexts and, more broadly, about how the fields of politics, business and society are inextricably related.
The count/mass distinction in Taurepang
Authors: Coutinho Costa Isabella
Published: May 2020

This paper presents a description of the count/mass distinction in Taurepang, a Cariban language spoken in Brazil and
Venezuela. The methodology used was based on Lima & Rothstein’s questionnaire (this volume). We show that Taurepang is a bare noun
language and that mass and count nouns can be pluralized. Despite nominal quantifiers have the same distribution, they show different
interpretation with count and mass nouns. As the data also shows that numerals distinguish count and mass nouns and that container phrases
trigger the count/measure interpretation, we assume here that the denotation of mass nouns in Taurepang cannot be count.
Compliment response behavior among Japanese-English bilinguals on Facebook
Authors: Ruiz-Tada Marina , Fernández-Villanueva Marta , Tragant Elsa
Published: May 2020

This study examines compliment responses on Facebook produced by Japanese-English bilingual women who post photos of their manicures and pedicures – the objects of praise. It is based on a total of 178 responses directed towards Japanese monolinguals, (American) English monolinguals, and Japanese-English bilingual audiences. The responses were coded according to Holmes (1986) and Placencia, Lower, and Powell’s (2016) taxonomies of compliment response strategies. Results indicated that acceptance of compliments was the most common strategy used by the Japanese-English bilingual women in the study, followed by evasion, rejection, and no acknowledgement. The study also highlights the importance of further examining the online practices of bilinguals who interact with multilingual audiences in compliment response research.
“I want your brain”
Authors: Heaney Dermot Brendan
Published: May 2020

This chapter examines complimenting behavior in Over by Over cricket commentary (OBO), a hybrid online genre with a conspicuous level of audience participation. The genre is defined and described and its social media credentials are assessed. The resulting picture is of an asymmetrical and time-bound virtual grouping in which simulated interactions between journalists and readers are increasingly to the fore.

A significant presence of compliments was noted in preliminary readings. For insights into their forms and function, a corpus of commentary on two days’ play in separate international cricket matches was analyzed for complimenting content. Contrary to findings in previous studies for other social media, although direct explicit compliments comprised the majority, most occurred in non-formulaic patterns. A number of explanations for this are proposed.
Modified self-praise in social media
Authors: Luo Mufan , Hancock Jeffrey T.
Published: May 2020

Compliments that have the speaker as their referent can be referred to as self-praise. This chapter introduces humblebragging, a modified self-praise speech act that involves both an expression of self-promotion and a modesty element to convey favorable impressions to others. Drawing on literature in both pragmatics and social psychology, we examine the components of humblebrags and how humblebrags can influence impression formation, and we consider how this distinct form of self-praising behavior may be shaped by social media. Finally, we report on an empirical study of the perceptions of humblebrags that finds that humblebrags posted on Facebook are perceived as less honest than straightforward brags and that humblebraggers are viewed as less sincere than braggers, when they received negative social evaluations. The results reveal that humblebragging may undermine the goal of presenting oneself as sincere on social media.
Harvesting of Arthrospira platensis by flocculation with phytic acid from rice bran
Authors: Zhu Jiangyu , Wakisaka Minato
Published: May 2020

The recovery of algal biomass is one of the critical steps involved in the commercial production of beneficial metabolites from Arthrospira platensis. Efficient and safe harvesting methods that do not sacrifice quality of final product are important for commercial application. Phytic acid (PA) is a natural non-toxic phytochemical widely distributed in plant tissues. Effect of PA from rice bran on the growth, trichome morphology such as spiral number and algal filament length, and harvesting efficiency of A. platensis were investigated. Cells aggregated into large cell flocs after the addition of PA in the medium, and algal spiral number and filament length increased. UV-vis spectra indicated the interactions between PA and algal cells. Adding PA at stationary growth phase is a good strategy for harvesting, since no adverse effect to biomass growth and harvesting efficiency. Harvesting efficiency of 95.69% at 0.5% (v/v) PA was superior to other conventional harvesting methodologies.

Abbreviations

PA: Phytic acid; PUFAs: Polyunsaturated fatty acids; FAO: Food and Agriculture Organization; γ-PGA: Poly (γ-glutamic acid); CNF: Cellulose nanofibrils; NIES: National Institute for Environmental Studies; SOT: Spirulina–Ogawa–Terui; CG: Control group; pI: Isoelectric point.