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• The GO-PA coating has been demonstrated for the first time to inhibit wax. • Superhydrophilic and underwater superoleophobic property was achieved via GO-PA coating on carbon steel surface. • Optimised GO-PA carbon steel surface showed up to 89.5 % enhancement in oil passing speed in pipe transportation. • Wax inhibition efficiency of 95.8% was achieved with the optimised GO-PA carbon steel surface. • Mechanical and chemical stable GO-based coating was achieved via one-step low-cost approach. Wax deposition in pipelines is a global issue during the production and transportation of oil. Recently, superhydrophilic/underwater superoleophobic coatings have garnered much attention due to their wax inhibition potential based on water film theory. Herein, carbon steel (CS) substrates were made superhydrophilic by coating phytic acid (PA) functionalised graphene oxide (GO) materials prepared by very simple process. The superhydrophilic GO-PA coatings induced the formation of a hydration layer on the surface, thus inherently showing underwater superoleophobic properties in a water-contained waxy oil system. The optimised GO-PA/CS surface possessed a water contact angle of nearly 0° and an underwater oil contact angle of ∼ 160°. This coating demonstrated up to 89.5 % enhancement in oil passing speed during the oil transportation test. This enhancement is particularly significant for reducing wax deposition in laminar and transitional flow regimes. Moreover, in the cold-finger wax deposition tests, a wax inhibition efficiency of 95.8 % was achieved with the optimised GO-PA/CS surface in the laminar flow regime. Therefore, this research provides insights into a mechanically and chemically stable GO-based coating achieved via a facile one-step functionalisation, which has not been previously reported in the literature for applications in waxy oil transportation. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the contracting behaviour of participants in the spot freight market for tankers by analysing the positioning of vessels at the time of fixture. For that purpose, we create a new dataset obtained by merging spatial ship positions, commercial fixtures and technical vessel specifications. Using quantile and quantile fixed effect regressions, we show how market conditions, vessel characteristics and charterers' preferences affect the fixture location. Our main result is that oil buyers secure tonnage earlier during strong tanker markets and that the geography of trade creates natural decision points that dominate in the spatial distribution of fixtures. [ABSTRACT FROM AUTHOR]

Two diesel oil-in-water emulsions were formed by using positively charged alumina nanoparticles solely and negatively charged silica nanoparticls solely as emulsifier, respectively. The formal systems are typical Pickering emulsions in which alumina nanoparticles adsorb at oil/water interface endowing droplets very good stability, whereas the later systems are non-Pickering emulsions in which silica nanoparticles do not adsorb at oil/water interface but distribute in aqueous phase surrounding the droplets endowing droplets temporary stability. Trace amounts of anionic surface-active materials in the diesel oil are responsible for the formation of two different emulsions. In the Pickering emulsions they adsorb at alumina particle surface to endow particle surface activity via in situ hydrophobization, whereas in the non-Pickering emulsions they adsorb at oil/water interface constituting a novel emulsion co-stabilized by like charged surfactants and nanoparticles at very low concentrations. By addition of trace amount of extra anionic surfactant, such as 0.1 mM sodium dodecyl benzene sulfate (SDBS), the novel diesel oil-in-water emulsions with good temporary stability can be formed by using silica nanoparticles at a concentration as low as 0.01 wt%. The emulsions can be demulsified easily by addition of trace amount (0.06∼0.1 mM) of a cationic surfactant such as cetyltrimethylammonium bromide (CTAB), or a low concentration (0.6∼3.0 mM) of divalent electrolyte such as CaCl 2 , and therefore have potential applications in oil transportation. On the other hand the Pickering diesel oil-in-water emulsions are relatively difficult to demulsify, and suitable demulsification protocols need to be developed for their applications in oil transportation. [ABSTRACT FROM AUTHOR]

• This paper determines the burst failure causes of a reinforced thermoplastic pipe (RTP). • The liner pipe and reinforced fibers were swelled by the conveying medium. • Mechanical and thermal properties of the liner pipe and reinforced fibers decreased significantly due to the swelling. • The direct cause of failure is that the damage of sealing rings lead to the leakage of conveying medium in the joint. • The reinforced fibers were contaminated with the leaking medium, resulting in the decreased pressure capacity of RTP. A burst failure occurred in a reinforced thermoplastic pipe used in an oil transportation system for 5 years. Visual inspection, tensile test, FTIR, TGA, VST, DSC, and pressure test were conducted to find out the failure cause. The results show that the damage to sealing rings led to the leakage of conveying medium in the joint. The fibers in the reinforcement layer were contaminated by the leaked conveying medium, resulting in performance degradation. The tensile strength and elongation at break of the fiber all decreased by 60 ∼ 80%. The burst pressure of the contaminated pipe is only 6 ∼ 7 MPa, far lower than its PN. According to the operating record, the highest working pressure ever reached 5.2 MPa during the operation, which approached its burst pressure. Meanwhile, there were pressure fluctuations during the operation. When the transient pressure was higher than the burst pressure of the contaminated pipes, burst failure occurred. [ABSTRACT FROM AUTHOR]

A rapid increase in maritime traffic together with challenging navigation conditions and a vulnerable ecosystem has evoked calls for improving maritime safety in the Gulf of Finland, the Baltic Sea. It is suggested that these improvements will be the result of adopting a regionally effective proactive approach to safety policy formulation and management. A proactive approach is grounded on a formal process of identifying, assessing and evaluating accident risks, and adjusting policies or management practices before accidents happen. Currently, maritime safety is globally regulated by internationally agreed prescriptive rules, which are usually revised in reaction to accidents. The proactive Formal Safety Assessment (FSA) is applied to risks common to a ship type or to a particular hazard, when deemed necessary, whereas regional FSA applications are rare. An extensive literature review was conducted in order to examine the opportunities for developing a framework for the GoF for handling regional risks at regional level. Best practices were sought from nuclear safety management and fisheries management, and from a particular case related to maritime risk management. A regional approach that sees maritime safety as a holistic system, and manages it by combining a scientific risk assessment with stakeholder input to identify risks and risk control options, and to evaluate risks is proposed. A regional risk governance framework can improve safety by focusing on actual regional risks, designing tailor-made safety measures to control them, enhancing a positive safety culture in the shipping industry, and by increasing trust among all involved. [ABSTRACT FROM AUTHOR]

Abstract: The semi-Markov model of the system operation processes is proposed and its selected characteristics are determined. A system composed on multi-state components is considered and its reliability and risk characteristics are found. Next, the joint model of the system operation process and the system multi-state reliability is applied to the reliability and risk evaluation of the port oil pipeline transportation system. The pipeline system is described and its operation process unknown parameters are identified on the basis of real statistical data. The mean values of the pipeline system operation process unconditional sojourn times in particular operation states are found and applied to determining this process transient probabilities in these states. The piping different reliability structures in various its operation states are fixed and their conditional reliability functions on the basis of data coming from experts are approximately determined. Finally, after applying earlier estimated transient probabilities and system conditional reliability functions in particular operation states the unconditional reliability function, the mean values and standard deviations of the pipeline lifetimes in particular reliability states, risk function and the moment when the risk exceeds a critical value are found. [Copyright &y& Elsevier]

This study examines the dynamic relationship between global economic policy uncertainty (GEPU) and tanker freight rates in both time- and frequency-domains. The tanker shipping market is shown to be susceptible to global political and economic risks. Given the recent high economic policy uncertainty pertaining to the world and the important role maritime transport plays in the global oil trade, it is a vital task to evaluate the dependence dynamics between economic policy uncertainty and tanker freight rates. The return series are first decomposed into different frequency components using wavelets in order to identify the dependence structure in different time scales. Second, the average and tail dependence behaviors are depicted using a wide range of both static and time-varying copula functions. The empirical results demonstrate significant time variations in the dependence structure between GEPU and tanker freight indices over different time scales. The results of this study convey significant policy implications and strategic planning for energy transport players. • Examines dependency between global economic policy uncertainty (GEPU) and tanker freight rates. • Considers both time and frequency domains. • Uses discrete wavelet decomposition to decompose original series into different time scales. • Depicts average and tail dependence using a wide range of static and time-varying copulas. • Results convey significant policy implications for energy transport players. [ABSTRACT FROM AUTHOR]

Abstract: The semi-Markov model of the system operation processes is proposed and its selected parameters are determined. The series ‘m out of k n ’ multi-state system is considered and its reliability and risk characteristics are found. Next, the joint model of the system operation process and the system multi-state reliability and risk is constructed. Moreover, reliability and risk evaluation of the multi-state series ‘m out of k n ’ system in its operation process is applied to the port oil transportation system. [Copyright &y& Elsevier]

The essentials of multi-state system reliability analysis and an asymptotic approach to system reliability evaluation are introduced. The classes of limit reliability functions for multi-state series, parallel, series–parallel and parallel–series systems composed of different components are fixed. Moreover, auxiliary theorems useful in reliability evaluation of real technical large systems are presented. These are applied to reliability evaluation of an oil transportation system. Approximate mean values and standard deviations of this system lifetimes in the state subsets and in particular states are determined. This system risk function and the moment when the risk exceeds an admissible level are evaluated as well. The accuracy of the approximation is illustrated numerically and graphically. [Copyright &y& Elsevier]

• A simple method to functionalize copper surface by nanosecond laser directly writing, 30 seconds alkali assistant oxidation reaction and 3 minutes perfluoroalkyl thiolate reaction. • The functionalized copper surface possesses excellent superamphiphobicity, with little sliding angle to water, peanut oil and hexadecane. • By changing grid spacing of the laser ablation path, surfaces with tunable oil adhesion in air can be obtained. • Oil (peanut oil, γ = 34.5 mN m−1 and hexadecane, γ = 27.5 mN m−1) transportation can be accomplished successfully. Researchers have been chasing controlling liquid adhesion for decades. Up to now, there are plenty of publications about controlling water adhesion in air and controlling oil adhesion underwater. However, the regulation of oil adhesive ability on superamphiphobic surfaces in air has been rarely addressed. In this article, we reported a method to fabricate superamphiphobic surface showing outstanding superhydrophobicity as well as tunable oil adhesion. Herein, a laser-chemical hybrid method was utilized to obtain superamphiphobic surfaces. We fabricated grid-like microstructures on copper substrate by nanosecond laser directly writing (LDW), and created nanorods on the surface by a facile alkali assistant oxidation (AAO) reaction, which was followed by a perfluoroalkylthiolate (PF-thiolate) reaction. By changing the grid spacing (GS) during LDW, the as-prepared superamphiphobic surface showed tunable oil adhesion, and oil (e.g., peanut oil and hexadecane) droplets could easily rolled-off from the surface (i.e., ultralow adhesion) or totally adhered to the surface (i.e., ultrahigh adhesion), upon which we realized oil droplets transportation. This work may provide a simple method of fabricating superamphiphobic surface and controlling oil adhesion in atmosphere, which can be potentially applied in numerous fields like microdroplet manipulation, microfluidic chips, microreactors and so on. [ABSTRACT FROM AUTHOR]

Oil spills can result in changes in chemical contaminant concentrations along coastlines. When concentrations are measured along the Gulf of Mexico over time, this information can be used to evaluate oil spill shoreline exposure dates. The objective of this research was to identify more accurate oil exposure dates based on oil spill chemical concentrations changes (CCC) within sediments in coastal zones after oil spills. The results could be used to help improve oil transport models and to improve estimates of oil landings within the nearshore. The CCC method was based on separating the target coastal zone into segments and then documenting the timing of large increases in concentration for specific oil spill chemicals (OSCs) within each segment. The dataset from the Deepwater Horizon (DWH) oil spill was used to illustrate the application of the method. Some differences in exposure dates were observed between the CCC method and between oil spill trajectories. Differences may have been caused by mixing at the freshwater and sea water interface, nearshore circulation features, and the possible influence of submerged oil that is unaccounted for by oil spill trajectories. Overall, this research highlights the benefit of using an integrated approach to confirm the timing of shoreline exposure. Image 1 • A new method is developed to compute oil exposure dates and regions. • Dates and regions were computed from concentrations of shoreline sediments. • Differences were observed against exposure dates predicted by oil spill trajectories. • Nearshore circulation features appear to account for some differences. • Cyclones also appear to influence exposure dates. Shoreline oil exposure dates were computed from concentrations of shoreline sediments measured during an oil spill. [ABSTRACT FROM AUTHOR]

The SFOSRC is sponsored by the U.S. Coast Guard's R&D Center as a regional center-of-excellence. Three projects are underway: the Straitsof Florida Nowcast/Forecast System (SFNFS), Oil Spill Information Management System (OSIMS), and National Marine Oil Transportation System (NMOTSM). SFNFS has evolved working-prototype, real-time circulation and trajectory models in a workstation environment. OSIMS is developing a prototype information system which integrates static geographical, ecological, regulatory, and response technology information withdynamic oceanic and atmospheric information. NMOTSM is developing a mathematical model for the transportation of oil in the U.S. EEZ, including major marine ports. Only SFNFS is described further here. SFNFS is based upon the Princeton Ocean Model, a state-of-the-science baroclinic model. It is forced by a feature model for the Florida Current on the inflow and by synoptic winds. High-resolution, realistic bottom topography is used, and the model is run on a c. 5.5 x 5.5 km grid with 21 sigma (terrain-following) levels. Every 12 h, the model is updated with fresh wind-forcing at 6 h intervals, out to 48 h from NMCs eta model. For specified spill location and time, surface trajectories are calculated, taking into account the ambient currents, directwind drift, and subgrid scale turbulent dispersion. [ABSTRACT FROM AUTHOR]