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AbstractLiquid metal (LM) plasma-facing components (PFCs) may provide a resolution to the challenging fusion environment, particularly the first wall and divertor surfaces. Transforming these concepts into viable technologies will require considerable research and development. With the fusion nuclear regime in mind, the Fusion Energy System Studies group examined LM PFCs in order to identify needed research thrusts that could accelerate their development and assess their viability. Liquid metal behavior, solid substrate aspects, and fusion facility integration aspects are examined, with concepts as the research focusing element. The concepts applied to a fusion nuclear device are the primary definer of the LM parameters, environmental conditions, and operational aspects. This forms the research strategy recommended for these complex systems.

Wound management is frequently performed in the community and forms a large part of daily activities of General Practice health professionals. However, previous research has acknowledged a need for further education and training on evidence based wound management for these health professionals.

Diabetes mellitus (DM) is a of group metabolic diseases which are defined by hyperglycaemia affecting multiple organs. The condition is found in people of all ages and ethnicities. Diabetes mellitus affects 180 million people worldwide and increasing numbers of patients are presenting with diabetic complications and the need for surgical intervention. This article describes the pathophysiology of DM and the management of the condition, particularly type I and type 2, in the perioperative phase of the surgical patient journey.

Photochemical reactions are essential to a large number of important industrial and biological processes. A method for monitoring photochemical reaction kinetics and the dynamics of molecular excitations with spatial resolution within the active molecule would allow a rigorous exploration of the pathway and mechanism of photophysical and photochemical processes. Here we demonstrate that laser-excited muon pump–probe spin spectroscopy (photo-μSR) can temporally and spatially map these processes with a spatial resolution at the single-carbon level in a molecule with a pentacene backbone. The observed time-dependent light-induced changes of an avoided level crossing resonance demonstrate that the photochemical reactivity of a specific carbon atom is modified as a result of the presence of the excited state wavefunction. This demonstrates the sensitivity and potential of this technique in probing molecular excitations and photochemistry.

The paper describes research needs in primary R&D areas for the family of dual-coolant lead-lithium (DCLL) blankets. Associated key scaling parameters are introduced and evaluated under conditions of FNSF, ITER and DEMO and also for the existing non-fusion MHD facilities, using the MaPLE loop at UCLA as an example. Comparisons among these parameters are recommended for measuring the R&D progress on the pathway from the present experimental facilities to FNSF. Possible experiments both in the existing facilities and FNSF are discussed along with the flow diagnostics.

The proposed Fusion Nuclear Science Facility (FNSF) represents the first facility to enter the complex fusion nuclear regime, and its technical mission and attributes are being developed. The FNSF represents one part of the fusion energy development pathway to the first commercial power plant with other major components being the pre-FNSF research and development, research in parallel with the FNSF, pre-DEMO research and development, and the demonstration power plant (DEMO). The Fusion Energy Systems Studies group is developing the technical basis for the FNSF in order to provide a better understanding of the demands on the fusion plasma and fusion nuclear science programs.

Temperature is an important factor influencing the biology of organisms and is intrinsically linked to climate change. The establishment of trematodes in target hosts is potentially susceptible to temperature changes effecting parasite infectivity or host susceptibility, and therefore in order to develop predictive frameworks of host–parasite dynamics under climate change large-scale analyses are required. The present study analyses the thermodynamics of the infectivity of larval trematodes including miracidia, cercariae and metacercariae from experimental data contained in the scientific literature using the Arrhenius critical incremental energy of activation (E*), an accurate measure of temperature-driven reaction rates. For miracidia and cercariae, infectivity increases as the temperature rises reaching a plateau over optimal thermal ranges before declining at higher temperatures. In contrast, metacercarial infectivity is at its greatest at low temperatures, declining with increasing temperature. [ABSTRACT FROM PUBLISHER]

SUMMARY: Temperature is an important factor influencing the biology of ectothermic organisms and is intrinsically linked to climate change. Trematodes are potentially susceptible to temperature changes and in order to develop predictive frameworks of their responses to climate change large-scale analyses are needed. The present study, using the Q 10 value, analyses experimental data from the scientific literature on the effects of temperature on cercarial development and emergence across a wide range of temperature in low (⩽35°) and mid-latitude (36–60°) species. Temperature appears to have no significant effect on the rate of development of cercariae within molluscan hosts. Data on cercarial emergence, corrected to incorporate the minimum emergence temperature threshold (METT) and acclimation status, was found to be largely unaffected by temperature over optimum ranges of ≈20 °C (15–25 °C) for mid-latitude species and ≈25 °C (20–30 °C) for low-latitude species. In addition, a decline in emergence rates was shown at higher temperatures. These results are contrary to a previous study on the meta-analysis of cercarial emergence. Some evidence of strain-specific differences and thermostability over a wide temperature range for both cercarial development and emergence was apparent. The significance of these results in furthering our understanding of cercarial biology under natural conditions is discussed. [ABSTRACT FROM AUTHOR]

AbstractUnder the US Fusion Nuclear Science and Technology Development program, we have selected the Dual Coolant Lead Lithium concept (DCLL) as a reference blanket, which has the potential to be a high performance DEMO blanket design with a projected thermal efficiency of >40%. Reduced activation ferritic/martensitic (RAF/M) steel is used as the structural material. The self-cooled breeder PbLi is circulated for power conversion and for tritium breeding. A SiC-based flow channel insert (FCI) is used as a means for magnetohydrodynamic pressure drop reduction from the circulating liquid PbLi and as a thermal insulator to separate the high-temperature PbLi (~700°C) from the helium-cooled RAF/M steel structure. We are making progress on related R&D needs to address critical Fusion Nuclear Science and Facility (FNSF) and DEMO blanket development issues. While performing the function as the Interface Coordinator for the DCLL blanket concept, we were developing the mechanical design and performing neutronics, structural and thermal hydraulics analyses of the DCLL TBM module. We estimated the necessary ancillary equipment that will be needed at the ITER site, and a detailed safety impact report was prepared. This provided additional understanding of the DCLL blanket concept in preparation for the FNSF and DEMO. This paper is a summary report on the progress of the DCLL TBM design and R&D for the DCLL blanket concept.

Miracidia are short-lived, non-feeding (lecithotrophic) free-living stages of trematodes, whose survival is potentially influenced by temperature. Climate change may result in elevated temperatures affecting trematode transmission. Therefore understanding their thermobiology forms an important step in determining the future dynamics of parasite populations. An empirical relationship exists between the mean expected life span of lecithotrophic larvae and the half life of their population (t0·5) and therefore t0·5 is a good indicator of glycogen utilization. In this study experimental data on the effects of temperature on miracidial survival were compiled from the scientific literature and evaluated in terms of metabolism using Q10 and Arrhenius activation energy (E* or μ). Temperature poorly influenced survival/metabolism with all miracidia having distinct zone(s) of thermostability. Overall there were few differences in Q10 and E* values between most species temperature ranges whilst there were only limited strain-specific variations in thermal responses of laboratory-maintained Schistosoma mansoni. Miracidia demonstrated a trend of greater thermal resistance than cercariae. In particular, comparative studies on 4 strains of the same species of miracidia and cercariae showed little correlation in thermal biology between the 2 life-history stages. The importance of these results for trematode transmission under global climate change is discussed. [ABSTRACT FROM PUBLISHER]

Cercariae are non-feeding free-living stages in the life cycles of trematodes, highly influenced by temperature. Their life span is brief, limited by the depletion of a non-renewable glycogen store. Warmer temperatures under the influence of climate change may promote the transmission of parasites and therefore understanding their thermobiology forms an important step in discerning the future dynamics of parasite populations. An empirical relationship exists between cercarial mean expected life span and the half-life of the population (t0·5) and therefore t0·5 is a good indicator of glycogen utilization. In this study experimental data on the effects of temperature on cercarial survival is compiled from the scientific literature and evaluated in terms of metabolism using Q10 and Arrhenius activation energy (E* or μ), common measures of temperature-mediated reaction rates. Cercariae have a variable response to temperature, which does not appear to be influenced by their life-history attributes or size. There were little differences in Q10 and E* values between most temperature ranges. In almost half the studies examined (7 of 16) cercariae demonstrated a discrete zone of thermostability over a range equivalent to typical individual mean summer temperatures. Distinct intraspecific differences in temperature responses between 3 laboratory strains of Schistosoma mansoni and 2 natural strains of Echinoparyphium recurvatumsensu stricto were apparent. The importance of these results for cercarial biology under global climate change is discussed. [ABSTRACT FROM AUTHOR]

AbstractThis paper describes a high-temperature ultrasonic Doppler Velocimetry (HT-UDV) technique that has been successfully applied to measure velocity profiles of the lead-lithium eutectic alloy (PbLi) flows. The impact of tracer particles is investigated to determine requirements for HT-UDV measurement of PbLi flows. The HT-UDV system is tested on a PbLi flow driven by a rotating-disk in an inert atmosphere. We find that a sufficient amount of particles contained in the molten PbLi are required to successfully measure PbLi velocity profiles by HT-UDV. An X-ray diffraction analysis is performed to identify those particles in PbLi, and indicates that those particles were made of the lead mono-oxide (PbO). Since the specific densities of PbLi and PbO are close to each other, the PbO particles are expected to be well-dispersed in the bulk of molten PbLi. We conclude that the excellent dispersion of PbO particles enables the HT-UDV to obtain reliable velocity profiles for operation times of around 12 hours.

AbstractJapan-US cooperation program TITAN (Tritium, Irradiation and Thermofluid for America and Nippon) started in April 2007 as 6-year project. This is the summary report at the midterm of the project. Historical overview of the Japan-US cooperation programs and direction of the TITAN project in its second half are presented in addition to the technical highlights.

AbstractLiquid metal breeders such as Lithium or the eutectic Lead-Lithium alloy PbLi have the potential for attractive breeding blankets, especially if the liquid metal serves as breeder and coolant. However, cooling of first wall and blanket structure is a challenging task because the magnetic field degrades the heat transfer and can cause a really high pressure drop. To overcome these problems, dual coolant blankets with helium cooled FW/blanket structure and a self-cooled breeding zone had been proposed, with electrical insulation by ceramic-coatings or sandwich flow channel inserts. Such concepts are in principle simpler than helium cooled blankets, but the thermal efficiency is limited to ˜35 % as in any helium cooled blankets with steel structure. A much higher efficiency up to about 45 % became feasible when the sandwich insulator was replaced by flow channel inserts (FCI) made of a SiC composite. This FCI serves as thermal insulator too, allowing an exit temperature of ˜700° C, suitable for a BRAYTON cycle power conversion system.The subject of this paper is a description of the Lead-Lithium blanket development and the major improvements on the dual coolant Lead-Lithium (DCLL) blanket concept achieved in the US during the last 10 years.

Nematodes are common parasites of molluscs but are often overlooked. Both metastrongyloid and rhabditoid species dominate the fauna within land snail and slug populations. Nevertheless, a key characteristic of many laboratory studies is the ability of these terrestrial nematodes to utilize aquatic molluscs as auxiliary hosts. The significance of this to the ecology of the parasite has never been evaluated. There is increasing concern as to the impact of climate change on the epidemiology of many parasitic diseases. In particular, it has been suggested that host switching may increase under the pressure of extreme climatic conditions. It is therefore timely to assess the role that aquatic molluscs may play in transmitting terrestrial nematodes, which include species of medical and veterinary importance such as Angiostrongylus cantonensis, A. vasorum, and Muellerius capillaris. The present review assesses the mechanisms of terrestrial nematode transmission through aquatic molluscs focusing on metastrongyloid and rhabditoid species, the importance of variable susceptibility of molluscan hosts, field studies on natural occurrence within aquatic habitats, and the impact of extreme climatic events (floods and droughts) that may increase in frequency under climate change. [ABSTRACT FROM AUTHOR]

AbstractAn investigation of MHD effects on a Flibe (Li2BeF4) simulant fluid has been conducted under the US-Japan JUPITER-II collaboration program using “FLIHY” pipe flow facility at UCLA. The present paper reports a development of unique experimental techniques using aqueous solution of potassium hydroxide as a Flibe simulant. In order to apply a particle image velocimetry (PIV) technique for magnetic field condition, special optical devices were developed. The PIV measurements of MHD turbulent pipe flow at Re = 5300 were performed, and modification of the mean flow velocity as well as turbulence suppression was observed. A flat velocity profile in the pipe center and a steep velocity gradient in the near-wall region at Ha = 20 exhibits typical characteristics of Hartmann flow.

AbstractFusion reactors designs frequently involve the use of liquid metal flows in the presence of strong magnetic fields. Simulation of the flows involves the solution of continuum equations for fluid flow and magnetic induction, usually done with finite difference methods. In this paper, an alternative method, based on the generalized lattice Boltzmann equation (GLBE), and implemented in the MetaFlow code is discussed. It has a number of desirable features, including fast execution, excellent parallel scalability, and can easily handle complex geometries. The use of the recent GLBE variant greatly enhances stability and accuracy. To simulate magnetohydrodynamic (MHD) flows relevant to fusion applications using GLBE, several new models have been developed, including new boundary condition formulations, preconditioners for faster steady-state convergence, variable electrical conductivity materials, and to resolve thin Hartmann layers. These models are discussed, and validations against MHD benchmarks, including 3-D driven cavity, high Hartmann number and turbulent cases are presented.

AbstractAn investigation of MHD effects on Flibe simulant fluid (aqueous potassium hydroxide solution) flows has been conducted under the U.S.-Japan JUPITER-II collaboration program using “FLIHY” pipe flow facility at UCLA. Mean and fluctuating temperature profiles in a conducting wall pipe were measured for low Reynolds number turbulent flows using a thermocouples probe at constant heat flux condition. It is suggested that the temperature profiles are characterized by interaction between turbulence production, turbulence suppression due to magnetic field and thermal stratification occurred even under the situation where quite small temperature difference exists in the pipe cross-section.

AbstractIn the dual-coolant lead lithium (DCLL) blanket, the key element is the flow channel insert (FCI) made of a silicon carbide composite (SiCf/SiC), which serves as electric and thermal insulator. The most important magnetohydrodynamic (MHD) and thermal issues of the FCI, associated with MHD flows and heat transfer in the poloidal channel of the blanket, were studied with numerical simulations using the U.S. DEMO DCLL design as a prototype. The mathematical model includes the two-dimensional momentum and induction equations for a fully developed flow and the three-dimensional (3-D) energy equation. Two FCI modifications, one with no pressure equalization openings and one with a pressure equalization slot, have been considered. The computations were performed in a parametric form, using the electric and thermal conductivity of the SiCf/SiC as parameters. Under the DEMO reactor conditions, parameters of the FCI have been identified that result in low MHD pressure drop and low heat leakage from the breeder into the helium flows. This paper also discusses the role of the pressure equalization openings, 3-D flow effects, and the effect of SiCf/SiC anisotropy.

AbstractThe US Advanced Limiter-divertor Plasma-facing Systems (ALPS) program is developing the science of liquid metal surface divertors for near and long term tokamaks. These systems may help solve the demanding heat removal, particle removal, and erosion issues of fusion plasma/surface interactions. ALPS combines tokamak experiments, lab experiments, and modeling. We are designing both static and flowing liquid lithium divertors for the National Spherical Torus Experiment (NSTX) at Princeton. We are also studying tin, gallium, and tin-lithium systems. Results to date are extensive and generally encouraging, e.g., showing: 1) good tokamak performance with a liquid Li limiter, 2) high D pumping in Li and non-zero He/Li pumping, 3) well-characterized temperature-dependent liquid metal surface composition and sputter yield data, 4) predicted stable low-recycle improved-plasma NSTX-Li performance, 5) high temperature capability Sn or Ga potential with reduced ELM & disruption response concerns. In the MHD area, analysis predicts good NSTX static Li performance, with dynamic systems being evaluated.

AbstractThe long-range goal of the Z-Pinch IFE program is to produce an economically-attractive power plant using high-yield z-pinch-driven targets (~3GJ) with low rep-rate per chamber (~0.1 Hz). The present mainline choice for a Z-Pinch IFE power plant uses an LTD (Linear Transformer Driver) repetitive pulsed power driver, a Recyclable Transmission Line (RTL), a dynamic hohlraum z-pinch-driven target, and a thick-liquid wall chamber. The RTL connects the pulsed power driver directly to the z-pinch-driven target, and is made from frozen coolant or a material that is easily separable from the coolant (such as carbon steel). The RTL is destroyed by the fusion explosion, but the RTL materials are recycled, and a new RTL is inserted on each shot.A development path for Z-Pinch IFE has been created that complements and leverages the NNSA DP ICF program. Funding by a U.S. Congressional initiative of $4M for FY04 through NNSA DP is supporting assessment and initial research on (1) RTLs, (2) repetitive pulsed power drivers, (3) shock mitigation [because of the high yield targets], (4) planning for a proof-of-principle full RTL cycle demonstration [with a 1 MA, 1 MV, 100 ns, 0.1 Hz driver], (5) IFE target studies for multi-GJ yield targets, and (6) z-pinch IFE power plant engineering and technology development. Initial results from all areas of this research are discussed.

AbstractAs candidate blanket concepts for a U.S. advanced reactor power plant design, with consideration of the time frame for ITER development, we assessed first wall and blanket design concepts based on the use of reduced activation ferritic steel as structural material and liquid breeder as the coolant and tritium breeder. The liquid breeder choice includes the conventional molten salt Li2BeF4and the low melting point molten salts such as LiBeF3and LiNaBeF4(FLiNaBe). Both self-cooled and dual coolant molten salt options were evaluated. We have also included the dual coolant leadeutectic Pb-17Li design in our assessment. We take advantage of the molten salt low electrical and thermal conductivity to minimize impacts from the MHD effect and the heat losses from the breeder to the actively cooled steel structure. For the Pb-17Li breeder we employ flow channel inserts of SiCf/SiC composite with low electrical and thermal conductivity to perform respective insulation functions. We performed preliminary assessments of these design options in the areas of neutronics, thermal-hydraulics, safety, and power conversion system. Status of the R&D items of selected high performance blanket concepts is reported. Results from this study will form the technical basis for the formulation of the U.S. ITER test module program and corresponding test plan.

AbstractThis paper provides a description of the most promising liquid breeder blankets currently proposed for testing in ITER. The critical MHD issues for selfcooled and dual coolant LM systems are the MHD pressure drop and flow distribution with ideal and imperfect insulator barriers/coatings, ideal and imperfect flow channel inserts, and complex geometry flow elements like expansions, contraction, manifolds, etc. Separately cooled LM systems still must circulate the LM for tritium removal, and similar MHD issues may limit flow velocity and influence tritium permeation due to creation of stagnant regions and other nonideal flow distribution effects. Molten salt breeder/coolants have significantly reduced electrical conductivity as compared to LMs, and MHD pressure drop is not considered a serious issue. However, MS also has much lower thermal conductivity, and the heat transfer to/from the structure depends on turbulent convection. The degradation of convective heat transfer by MHD turbulence modification/suppression is of great interest for both selfcooled MS systems where first wall cooling may need to be enhanced, and dual coolant MS systems where heat transfer from the hot breeder to the cooler wall needs to be suppressed. These issues are discussed in detail and development plans specifically for the dualcoolant PbLi concept, up to and including integrated testing in ITER, are presented.

AbstractTesting blanket concepts in the integrated fusion environment is one of the principal objectives of ITER. Blanket test modules will be inserted in ITER from Day 1 of its operation and will provide the first experimental data on the feasibility of the D-T cycle for fusion. With the US rejoining ITER, the US community has decided to have strong participation in the ITER Test Blanket Module (TBM) Program. A US strategy for ITER-TBM has evolved that emphasizes international collaboration. A study was initiated to select the two blanket options for the US ITER-TBM in light of new R&D results from the US and world programs over the past decade. The study is led by the Plasma Chamber community in partnership with the Materials, PFC, Safety, and physics communities. The study focuses on assessment of the critical feasibility issues for candidate blanket concepts and it is strongly coupled to R&D of modeling and experiments. Examples of issues are MHD insulators, SiC insert viability and compatibility with PbLi, tritium permeation, MHD effects on heat transfer, solid breeder “temperature window” and thermomechanics, and chemistry control of molten salts. A dual coolant liquid breeder and a helium-cooled solid breeder blanket concept have been selected for the US ITER-TBM.

The toxicity of cadmium and zinc at concentrations ranging from 0·1 to 10 000 μg/l to the life-span of decaudised cercarial bodies (cercariae that have shed their tails) of Diplostomum spathaceum was investigated. The effects of metal exposure at 3 temperatures (12, 20, and 25 °C) and 3 levels of water hardness (distilled water, soft water and hard water) were studied. In general, under most experimental conditions increasing metal concentrations reduced the life-span of decaudised cercariae. Increasing water hardness and decreasing water temperature caused an increase in the life-span of both control and metal exposed decaudised cercariae. However, at certain isolated metal concentrations, associated with a specific level of water hardness and temperature, increased survival above controls occurred. Differences in the relative toxicity of cadmium and zinc were dependent on the environmental conditions of exposure. The decaudised cercarial life-span under metal exposure was found to be generally independent of the overall cercarial survival and tail loss in most experimental conditions. Prolonged exposure to cadmium and zinc caused changes in the decaudised cercarial life-span when compared to individuals decaudised during the initial 24 h exposure period to those which were decaudised during the final 24 h period of cercarial survival. The validity of studying the decaudised cercarial life-span as an indicator of ‘fitness’ of larvae to migrate through the tissues of the target fish host, in terms of glycogen utilization, was assessed for those cercariae decaudised during the initial 24 h exposure period only. A limited reduction in the decaudised cercarial life-span during this period compared to controls was recorded, which may possibly indicate a reduced penetration ‘fitness’ of cercariae exposed to cadmium and zinc. The importance and relevance of these findings to parasite migration and establishment in the fish host are discussed.

The increased occurrence of pollutants in ecosystems is a continuing area of concern. It is known that numerous diseases of wild aquatic animals can occur with decreased or increased prevalences in areas associated with high or chronic levels of pollution. This may have serious implications for environmental health. There has consequently been an increasing number of laboratory and field studies on disease transmission under polluted conditions, especially focusing on digeneans of medical or economic importance. The effect of pollutants to the transmission of larval digeneans (miracidia, cercariae, metacercariae) and snail-digenean interactions is therefore considered. An overview and interpretation of the published literature on laboratory and field studies is provided. It is apparent from these studies that the influence of pollutants on digenean transmission is highly complex with much of the observed effects in the laboratory often masked by a complexity of other factors in the field. Future studies would benefit from a standardisation of experimental procedures, increasing the number of combined laboratory and field studies, and increasing the complexity of the experiments undertaken.

The effect of cadmium and zinc at concentrations ranging from 0.1 to 10000 μg/l on tail loss in cercariae of Diplostomum spathaceum was investigated at 3 temperatures (12, 20 and 25 °C) and 3 levels of water hardness (distilled water, soft water and hard water). Increasing tail loss over time was found to be linked with a parallel decrease in cercarial survival in controls. Exposure to the heavy metals induced, especially at high concentrations, a change in the relationship between cercarial tail loss and survival, causing either stimulation or inhibition of tail loss dependent on the individual toxic exposure. Under most environmental conditions the rate of tail loss over time was reduced by increasing metal concentrations. Inhibition of tail loss occurred in a limited number of both control and metal-exposed cercariae, with a number of low metal concentrations inducing greater inhibition than in controls. Stimulation of tail loss causing an increased tail loss rate above controls also occurred at certain high metal concentrations. Increasing water hardness and decreasing water temperature caused a reduced tail loss rate over time in both control and metal-exposed cercariae. However, with decreasing temperature a reduced rate of tail loss over time in metal-exposed cercariae compared to controls occurred at some low metal concentrations. When tail loss was compared against cercarial death of the experimental population toxic exposure induced changes in the parallel relationship of these parameters, dependent on individual metal concentration, water temperature and hardness. Differences in the relative effects of cadmium and zinc on cercariae were dependent on the environmental conditions of exposure. Both metals showed limited effects during the period of maximum cercarial infectivity (0–5 h). The mechanisms and importance of metal toxicity to cercarial tail loss are discussed.

In the APEX study, one of the tasks focuses on the exploration and identification of the attractive options and issues for flowing liquid lithium walls in the NSTX device. In addition to constraints imposed by the machine, the operating conditions of the flowing liquid walls along the center stack and divertor areas are guided by MHD and heat removal requirements. In this paper, we present important MHD and heat removal issues and analysis for the proposed free surface lithium flows under NSTX conditions. It is shown that of all MHD effects, the one caused by the normal magnetic field is the most important. The flow over the center stack area is not affected by MHD interaction significantly, whereas flow over the inboard divertor undergoes strong MHD drag resulting in flow thickening by several times. The flow over the outboard divertor is essentially stopped. The analysis shows that a flow with an inlet velocity of 2 m/s and film thickness of about 4 mm can be established to provide surface temperature less than 400° C for the center stack under a projected NSTX total heating power of 10 MW operation.

Experiments are under way at UCLA to simulate the liquid slab jets of the HYLIFE-II Inertial Fusion Reactor. Measurements of surface ripple and break-up length are made based on photographic images of the jet flow, and velocity data is obtained from an orifice-type flow meter. The experiment can be run with a selection of nozzles and upstream conditioners in order to determine the optimum configuration for suppressing disturbances. Preliminary data, taken while verifying the operation of the experimental system, indicate that the slab jets issuing from a nozzle comprisedslot cut in an orifice plate this nozzle type contract out of their initial rectangular shape more rapidly than would be expected from surface tension forces alone. Subsequent data are expected to aid in the proof-of-principle for thick liquid cavity designs, provide insight into design requirements of such systems, and increase the fundamental understanding of turbulent liquid jet flow in vacuum.

The attractive features and scientific challenges offered by the liquid wall systems render them strong candidates for investigation in the APEX project[1]. In particular, their high power density capabilities make the fusion reactors economically competitive. In this paper, as part of evolving a practical design based on this evolutionary idea, issues concerning thermalhydraulics of liquid surface first wall/blankets were analyzed. Design approaches as presently envisioned include both liquid films over the solid surface and gravity driven thick liquid jets using lithium and flibe as working fluids. The analyses involved defining liquid systems operating conditions, such as velocity and inlet/outlet temperatures, as well as to calculate free surface temperature so that the evaporation rate from the free surface would not jeopardize plasma operation while maintaining the liquid temperature within the operating windows for high thermal efficiencies. All analyses were performed for a neutron wall load of 10 MW/m2and its corresponding surface heat flux of 2 MW/m2. The results indicated that high velocities, hard x-ray spectra and turbulent heat transfer enhancement were necessary conditions for keeping flibe first wall temperature low. On the other hand, at velocities of 20 m/s or higher, it appears possible to maintain lithium film evaporation rate below 1020#/m2s in an ARIES-RS type configuration. Nevertheless, present analyses have not uncovered any basic flaws or major shortcomings in the underlying scientific or technical arguments for the concepts. Yet, engineering innovations of how to maintain and control the flow and the associated analyses are still needed.

Proc. Instn Civ. Engrs Civ. Engng, 102, Feb. 8-14 Paper 10275 L The London Ark N. Morley, BSc, MICE The London Ark in Hammersmithis an important building a promion nent site, made striking by the unique talents notable international of a architect. Its fresh and exciting concept has createda landmark in the field of office design, and the ground-breaking approach to manythe of technical problems involved makes it even greater interest. This Paper of describes the background to the project and the processeswhich by decisions were made by the joint British and Swedish team of architect, developer, project managers and consultants...

The efficacy and acceptability of 0.25% and 0.05% desoxymethasone, 0.1% betamethasone valerate and 1% hydrocortisone creams were compared in patients with eczema. A double-blind parallel group multi-centre design was employed in which 96 patients were recruited by four centres. Patients used one cream for a 3-week period and follow-up assessment visits were made at weekly intervals. Efficacy variables were: erythema/redness, scaling, itching and extent of area affected. These variables were assessed by both the investigator and the patient. The 0.25% desoxymethasone was the most effective treatment, producing the greatest degree of improvement in all clinical parameters, hydrocortisone was the least effective and 0.05% desoxymethasone was of intermediate effectiveness. The 0.1% betamethasone produced similar results to 0.25% desoxymethasone for half the assessments; for the other half the results were similar to 0.05% desoxymethasone. No adverse effects were reported during the study. The results are discussed in terms of physical properties of the vehicles and corticosteroid potency.