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Mosquitoes (Diptera: Culicidae) use certain resting sites during their inactive phase. The microclimatic conditions of these resting sites might affect their physiology and vectorial capacity. In this study, we combined a field and a laboratory study to investigate the natural resting site and temperature preferences of mosquitoes. The field study was conducted at a forest close to Oldenburg (Lower Saxony, Germany) from May to October 2018. Mosquitoes were collected in five different natural habitats with seven replicates each. Temperature was recorded hourly at each site. Significantly more mosquitoes were collected in deadwood (predominantly Culiseta morsitans/fumipennis) and shaded herb layer (predominantly Aedes species) compared to unshaded herb layer or broadleaf and coniferous trees. GLMMs revealed resting site habitats as the best predictor to explain the observed preference patterns, but microclimatic conditions are also involved in mosquito resting site selection. Most mosquitoes were collected at resting sites with relatively colder and more stable temperatures. In concert, laboratory choice experiments with a thermal gradient ring demonstrated that Cs. morsitans/fumipennis avoid temperatures over 30 °C. Understanding the small-scaled resting site preferences and the related microclimatic conditions can improve mosquito collection techniques and refine the prediction of mosquito-borne pathogen transmission.

The European Treatment and Disposal of Irradiated Graphite and other Carbonaceous Waste project sought to develop best practices in the retrieval, treatment, and disposal of irradiated graphite including other irradiated carbonaceous waste such as structural material made of graphite, nongraphitized carbon bricks, and fuel coatings. Emphasis was given on legacy irradiated graphite, as this represents a significant inventory in respective national waste management programs. This paper provides an overview of the characteristics of graphite irradiated during its use, primarily as a moderator material, within nuclear reactors. It describes the potential techniques applicable to the retrieval, treatment, recycling/reuse, and disposal of these graphite wastes. Considering the lifecycle of nuclear graphite, from manufacture to final disposal, a number of waste management options have been developed. These options consider the techniques and technologies required to address each stage of the lifecycle, such as segregation, treatment, recycle, and ultimate disposal in a radioactive waste repository, providing a toolbox to aid operators and regulators to determine the most appropriate management strategy. It is noted that national waste management programs currently have, or are in the process of developing, respective approaches to irradiated graphite management. The output of the Treatment and Disposal of Irradiated Graphite and other Carbonaceous Waste project is intended to aid these considerations, rather than dictate them.

Summary ExxonMobil Upstream Research Company (EMURC) recently completed a subsea technology development and qualification program that included performance testing of an inline electrocoalescer device supplied by FMC Technologies (FMC). This paper will summarize the results from these performance tests. Although heavy oil has been processed onshore successfully for many decades, processing heavy oil in deepwater, subsea, or Arctic fields is extremely challenging. One key challenge is oil/water separation, in which physical separation is constrained by the high viscosity of the crude and the narrow density difference between oil and water. Installing conventional electrostatic coalescers or dehydrators is often not economical or is impractical at remote locations. As part of ExxonMobil's subsea program, several different separation technologies have been investigated and tested that could enable development of these fields. One example of such a technology is an inline electrocoalescer device. An inline electrocoalescer device enhances the coalescence of water droplets dispersed in emulsified oils. This technology has the potential to improve the performance of the downstream oil/water separator considerably. By applying an electrical field to an oil/water mixture, the dispersed water droplets become polarized and reorient themselves in the electrical field. As these water droplets approach one another, attractive forces between the individual water droplets lead to coalescence. Larger water droplets that can be separated faster and more easily in the downstream separation equipment are formed. Such a device can be used to increase the throughput, performance, and reliability of existing oil-processing systems, while reducing the energy consumption and/or use of chemical demulsifiers. In new processing systems, either subsea or topside, deployment of such a device has the potential to significantly reduce the size and weight of the downstream separation equipment, thereby lowering the overall capital expenditure. The results presented in this paper are from performance tests that have been carried out on an inline electrocoalescer device at FMC's testing facilities in the Netherlands, with EMURC's involvement. Extensive testing was executed with both medium and heavy crude oils. The operating temperatures were varied in a range representative for subsea processing applications, where heating of the process fluids is difficult. Thus, the performance of the inline electrocoalescer device was evaluated over a range of oil viscosities. Water-in-oil concentration, flow velocity, upstream shear, and electrical-field strength were also varied to investigate their effects on the performance of the inline electrocoalescer device. The results demonstrate that the unit is able to deliver high preconditioning performance to medium- and heavy-crude-oil emulsions, provided that the appropriate process conditions and electrical settings are used.

The natural gas industry is increasingly pursuing compact and lower weight processing technology for offshore, onshore, remote, and challenged gas processing. Increased modularity of process equipment and process intensification require innovative solutions. ExxonMobil Upstream Research Company (EMURC) has developed and qualified a new inline dehydration technology meant to replace conventional TEG tower and associated separator vessels to meet pipeline dewpoint specifications. Compact Mass transfer and Inline Separation Technology (cMIST™) achieves this goal with significant reductions in weight and footprint. The cMIST™ dehydration system relies on state-of-the-art technological advances in contacting and inline separation to achieve pipeline specification dry gas and/or prevent hydrate formation. It includes a novel droplet generator which creates small, well-dispersed droplets with a high surface area for absorption followed by an inline separator. EMURC has completed the technical qualification for the cMIST™ dehydration system and effective December 1st 2016, this system has been exclusively licensed to Sulzer for global deployment in offshore and onshore facilities. The cMIST™dehydration system was demonstrated using a skid-mounted test unit in the Woodford trend area of Oklahoma, USA at an XTO Energy production facility. It was tested under a range of field conditions to examine the dehydration capacity, operability, and reliability of the technology and it achieved pipeline specification over a range of process conditions and during sustained operation. The cMIST™ dehydration system enables 50% dehydration system weight reduction and 50 - 80% absorber footprint reduction along with significant capital cost savings. The technology is highly modular to allow for simple transportation into remote, challenged, or offshore environments and provide installation configuration flexibility.

ExxonMobil Upstream Research Company recently completed a technology development and qualification program, which included performance tests on an integrated subsea compact separation system for ultradeepwater applications.

Increasing confidence and efficiency of process unit are major challenges for subsea field development. In such conditions, subsea liquid-liquid separation is still an important issue. Moreover, related to water depth, only compact separators with short residence times can be installed. The key point developed in this paper is to evaluate the water-oil separation regarding the oil properties including the effect of gas. A joint Industrial Program was performed in IFPEN on water separation efficiency in collaboration with Petrobras and ExxonMobil.Experiment and numerical analysis of tests were performed on a facility platform. The GOwSP platform used is an industrial test facility designed to research and to test multiphase equipments. The closed loop is under pressure and temperature control to simulate real operating conditions. The material used is a crude oil supplied by Petrobras, synthetic brine and natural gas. The tests were performed in a horizontal separator unit implemented with specific instrumentation such as interface profiler gauge. The separation efficiency is calculated from flow mass balance. Various operating conditions were studied such as; gas and liquid flow rates, water fraction, temperature, pressure. Special attention was taken on pressure effect and gas/oil ratio.Thus, a 1D model previously developed was used for tests simulation in order to predict the separation efficiency as a function of the operating production conditions. The 1D-model is based on an "experiment-modeling" methodology. The model is developed based on physical laws describing emulsion destabilization under only gravity effect and then it is extrapolated in case of fluid flows. Simulations shown a good accordance with experiment results. Whatever the conditions, most of simulation of the separation efficiency are within a 20% relative error margin. Classical behaviour of separation efficiency increase with oil residence time and temperature is confirmed as a decrease with initial water content increase. Simulations permitted to underline the important influence of oil characteristics viscosity, density on separation efficiency. At tested operating conditions, the gas had a slight influence on oil/water separation.

ExxonMobil Upstream Research Company (EMURC) recently completed a subsea technology development and qualification program which included performance testing of an integrated, subsea compact separation system with electrocoalescence for ultra-deepwater applications. To the authors' knowledge, this was the first time that an electrocoalescer had been tested with a gravity-based, compact separator (e.g., a Pipe Separator). One challenge often seen with conventional gravity separators is the formation and build-up of stable emulsion layers, mainly associated with the processing of medium and heavy oils. In an earlier test program, the Pipe Separator, the primary oil-water separator in the subsea compact separation system, performed well; however, emulsions that were not separated in the main pipes of the Pipe Separator tended to accumulate in the outlet section. There, the emulsion layer then had to either flow out of the oil outlet (penalty on the oil quality) or the water outlet (penalty on the water quality). The medium and heavy oil trials were particularly challenging, especially at lower water cuts. In order to achieve the desired oil and water qualities, the total liquid flow rate through the system had to be reduced. To overcome this limitation, additional trials were performed later with a compact electrocoalescer, the Compact Electrostatic Coalescer (CEC™) supplied by Fjords Processing (formerly Aker Process Systems), which effectively coalesced dispersed water droplets in the oil-continuous feed into larger droplets such that they could be separated easier in the downstream Pipe Separator. The results from the additional trials demonstrated that electrocoalescence enhanced the oil-water separation performance of the integrated system at flowing and operating conditions that would have otherwise been very challenging. This paper presents a summary of the results from these additional trials. The cost of developing and deploying a subsea separation system is significant; and therefore, it may not be economical if the system is unable to achieve a sufficient capacity. The design of subsea processing systems is often a balance between what is practically achievable under the module size/weight constraints, and what production rate is required for project economics. By understanding, with confidence, the maximum liquid handling capacity of the integrated system with electrocoalescence, technical risks could be minimized, and a future subsea separation project could become more attractive. As such, the results from this test program may be of interest to operating companies considering similar technologies or future subsea separation projects.

Abstract ExxonMobil Development Company (EMDC) recently completed a qualification program which included a multiphase, subsea separation system for shallow-water applications. This paper summarizes the results from this qualification program. Developments and advances in subsea processing technologies and the application of such technologies have been fueled by recent economic considerations in the oil and gas industry, as fields are maturing and operating companies strive to maintain oil and gas production. To-date, companies have executed project-specific qualification programs which take years of upfront engineering. The intent of this qualification program was to develop subsea separation technologies for the "global" subsea portfolio, rather than a specific project. To cover the "global" subsea portfolio, a separator design was chosen that would meet separation performance targets over a wide range of operating conditions. For subsea applications, availability and reliability is critical, as unplanned intervention costs are extremely high; therefore, only certain internals were recommended to avoid plugging and fouling issues. Also, the separator was equipped with sand handling internals, including sand jetting headers and sand removal cyclones, to allow online fluidization and removal of accumulated sand. Qualification activities included the development of a subsea processing template, design validation of a multiphase separator design using Computational Fluid Dynamics (CFD) and performance tests with model fluids and "live" fluids, and performance tests on the sand handling equipment. High-level results from these tests are shared. Prior to the qualification programs, experience with subsea separation technologies, and subsea processing as a whole, within ExxonMobil was limited to being an active partner with subsea processing projects such as Tordis and Pazflor. Following the execution of the aforementioned qualification programs, technical risks have been mitigated, such that it is now possible to be confident in applying these technologies in the "global" subsea portfolio. This will enable ExxonMobil to reduce the cost and schedule impact of upfront engineering on future subsea processing projects. In the ever-changing business environment of the oil and gas industry, this may become a preferred approach to bring unproven technologies to maturity when the business need is well-established.

We report results from a programme aimed at investigating the temperature of neutral gas in high-redshift damped Lyman-$\alpha$ absorbers (DLAs). This involved (1) HI 21cm absorption studies of a large DLA sample, (2) VLBI studies to measure the low-frequency quasar core fractions, and (3) optical/ultraviolet spectroscopy to determine DLA metallicities and velocity widths. Including literature data, our sample consists of 37 DLAs with estimates of the spin temperature $T_s$ and the covering factor. We find a strong $4\sigma$) difference between the $T_s$ distributions in high-z (z>2.4) and low-z (z1 sub-sample. Since z>1 DLAs have angular diameter distances comparable to or larger than those of the background quasars, they have similar efficiency in covering the quasars. Low covering factors in high-z DLAs thus cannot account for the observed redshift evolution in spin temperatures. (Abstract abridged.), Comment: 37 pages, 22 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Society

Abstract Offshore deepwater discoveries have driven the development of new compactseparation technologies, a core aspect of subsea processing. Compact separatorsare much smaller than conventional separators and have the potential tosignificantly reduce capital expenditure for deepwater developments. Unfortunately, reducing the size of separators generally reduce the separationperformance and the robustness to handle fluctuations in flow rate andcomposition. It is therefore essential to find an acceptable balance betweenthe realized reduction in overall capital expenditure and reduced tolerance tofluctuating conditions. To maximize the economics of a subsea development, itis important to understand how the technology selection impacts performance, risks, costs, and ultimately the attractiveness of deepwater subsea processing. Proactive technology screening and qualification are required. This paperpresents one of several ongoing joint industry projects to develop and screenseparation technologies for deepwater applications, the DEMO 2000 project: NextGeneration Deepwater Subsea Gas-liquid Separation System. An overview ofavailable technologies for separation in deep water is disclosed, includingcyclonic separators, compact gravity-type separators, and slug dampeningtechnologies. Their characteristics, typical performance and maturity level arediscussed. Finally, the program activities are explained and some highlightsfrom the separation test program are shared. Introduction Value Drivers for Subsea Gas-liquid Separation In recent years, subsea processing, and more specifically subsea separation, has been recognized as one of the most promising technology developments in theoffshore industry. With the recent success at Perdido [Ju et al., 2010], Parquedas Conchas (BC-10) [Iyer et al., 2010; Deuel et al., 2011], and Pazflor[Eriksen, 2012], subsea separation is attracting interest from industry becauseof its ability to increase production, enhance recovery, and improve fieldeconomics on a commercial scale. Subsea separation is, in general, stillconsidered an emerging technology area; therefore the benefits and capabilitiesmust be clearly demonstrated to infuse acceptance and confidence as thepreferred development option. McClimans and Fantoft [2006] and Di Silvestro etal. [2011] have presented a detailed review of the value drivers for subseagas-liquid separation, which is the topic of this paper. In summary, subseagas-liquid separation has proven to provide strong business incentives withenabling capabilities, including (i) more efficient liquid boosting, (ii)longer range gas compression from subsea to onshore, (iii) cost efficienthydrate management, (iv) effective riser slug depression, (v) and access tochallenging field developments that otherwise would be abandoned or notdeveloped (due to their remote location, harsh conditions, longer tie-backrequirements, or low reservoir drive). The main drivers are discussedbelow.

This work reviews the major published studies, both theoretical and experimental, that address the impact of wave motion on packed tower performance. Current practice is to add excess packing to guarantee the required separation is obtained, though there is little data available to derive a safety factor for packing height. This work highlights deficiencies in the current knowledge base and analyzes general trends to address common misconceptions about tower design for floating production. Tilt and motions imposed on a fractionation column have a significant impact on product specifications due to reduced packing efficiency. Improved awareness of motion impacts will assist the analysis of tower design and allow feedback to the process design. Identifying gaps in available data shows limits in the current understanding and allows the development of appropriate simplifying assumptions. The current understanding of towers in motion allows only very basic design rules and the safety factor for packing height in literature varies from 1.1 to 2.0. This provides little confidence in the ability to predict packing efficiency for floating production. Static tilt is more detrimental to liquid distribution than motion at a given amplitude. Still, liquid maldistribution from motion approaches that of static tilt as the period increases. Liquid sloshing, often cited as a significant concern, is a relatively minor contribution to maldistribution except for short periods and tall towers. The relative bed size has a significant impact on liquid maldistribution, limiting the recommended maximum bed height:column diameter to 2 – 3 to maximize the efficiency. Approach to equilibrium is often overlooked as the major determinant of sensitivity of efficiency to maldistribution. Separations that operate near equilibrium are more sensitive to maldistribution than services with a large driving force. Thus, distillation towers are generally more sensitive to motion than absorbers and sensitivity may vary over column height. Recommendations are provided for a bed-by-bed analysis and feedback to the process design. Floating production units require additional complexity and conservatism in tower design. An improved awareness of motion effects on towers, and the factors involved, will lead to improved designs and a reduction in the cost of floating production facilities.

A new European Project has been launched in April 2008 under the 7th EURATOM Framework Programme (FP7-211333), with a duration of four years, addressing the ‘Treatment and Disposal of Irradiated Graphite and other Carbonaceous Waste (CARBOWASTE)’. The objective of this project is the development of best practices in the retrieval, treatment and disposal of irradiated graphite & carbonaceous waste-like structural material e.g. non-graphitised carbon bricks and fuel coatings (pyrocarbon, silicon carbide). It addresses both legacy waste as well as waste from future generations of graphite-based nuclear fuel. After defining the various targets for an integrated waste management, comprehensive analysis of the key stages from in-reactor storage to final disposal will then be undertaken with regard to the most economic, environmental and sustainable options. This will be supported by a characterisation programme to localize the contamination in the microstructure of the irradiated graphite and so more to better understand their origin and the release mechanisms during treatment and disposal. It has been discovered that a significant part of the contamination (including 14 C) can be removed by thermal, chemical or even microbiological treatment. The feasibility of the associated processes will be experimentally investigated to determine and optimise the decontamination factors. Reuse of the purified material will also be addressed to close the ‘Graphite Cycle’ for future graphite moderated reactors. The disposal behaviour of graphite and carbonaceous wastes and the improvement of suitable waste packages will be another focus of the programme. The CARBOWASTE project is of major importance for the deployment of HTR as each HTR module generates (during a 60 years operational lifetime) about 5,000 to 10,000 metric tonnes of contaminated graphite containing some Peta-Becquerel of radiocarbon. It is strongly recommended to take decommissioning and waste management issues of graphite-moderated reactors already into account when designing new HTR concepts.Copyright © 2008 by ASME

This paper questions the extent to which developmental considerations have been incorporated into the theory and practice of cognitive behavioral therapy (CBT). It focuses on children aged between 5 and 8 years because Piagetian developmental theory places them at a prelogical cognitive level, and thus, the use of a therapeutic approach that is based on a rationalist paradigm would be considered inappropriate. The cognitive demands made upon 5- to 8-year-old children by CBT are outlined, and the current developmental literature is reviewed in the light of this to evaluate the cognitive abilities of this age group. The models underpinning CBT are examined for evidence of the influence of developmental psychology, and the outcome literature of CBT techniques is then scrutinized to evaluate the efficacy of these techniques with young children. Conclusions are reached regarding the appropriateness of current cognitive-behavioral approaches with young children, and the implications for alternative approaches are briefly considered.

The construction of Riga Dome Cathedral and its Capithullum hall were initiated in 1211. Through centuries they were damaged a lot due to migration of soluble salts and moisture. During the last restoration (1888-1891) a lot of mistakes were conceded and subsequently some of probable solutions for restoration were unsuccessful. In 2009 the new restoration stage in Capithullum hall was started. Two types of desalination methods were used in hall – desalination with lime-sand plaster and poultice of lignin. Both quantitative and semiquantitative chemical analyses were performed in order to appreciate the desalination process.