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International audience; Aquatic ecosystems are chronically exposed to radionuclides as well as other pollutants. Increased concentrations of pollutants in aquatic environments can present a risk to exposed organisms, including fish. The goal of this study was to characterize the effects of tritium, in the context of natural environments, on the health of fathead minnow, Pimephales promelas. Fish were exposed to tritium (activity concentrations ranging from 2 to 23,000 Bq/L) and also to various concentrations of several metals to replicate multiple-stressor environments. Fish were exposed for 60 days, then transferred to the tritium background site where they stayed for another 60 days. Tritium, in the forms of tritiated water (HTO) and organically bound tritium (OBT), and a series of fish health indicators were measured in fish tissues at seven time points throughout the 120 days required to complete the exposure and the depuration phases. Results showed effects of environmental exposure following the increase of tritium activity and metals concentrations in water. The internal dose rates of tritium, estimated from tissue HTO and OBT activity concentrations, were consistently low (maximum of 0.2 μGy/h) compared to levels at which population effects may be expected (> 100 μGy/h) and no effects were observed on survival, fish condition, gonado-somatic, hepato-somatic, spleno-somatic and metabolic indices (RNA/DNA, proteins/DNA and protein carbonylation (in gonads and kidneys)). Using multivariate analyses, we showed that several biomarkers (DNA damages, MN frequency, gamma-H2AX, SFA/MUFA ratios, lysosomal membrane integrity, AChE, SOD, phagocytosis and esterase activities) were exclusively correlated with fish tritium internal dose rate, showing that tritium induced genotoxicity, DNA repair activity, changes in fatty acid composition, and immune, neural and antioxidant responses. Some biomarkers were responding to the presence of metals, but overall, more biomarkers were linked to internalized tritium. The results are discussed in the context of multiple stressors involving metals and tritium. © 2017 Elsevier B.V.

The current Canadian and Romanian model predictions for tritium dose following an atmospheric tritiated hydrogen gas (HT) release is based on a default Canadian Standards Association (CSA) conversion factor of HT to tritiated water (HTO) of 4.3%. The determination of an empirical site specific value for the conversion factor was essential for the CANDU Cernavoda Nuclear Power Plant (NPP) in Romania to verify if the CSA value is appropriate for use at this site. Given the role of soil characteristics on the conversion of HT to HTO, on-site experiments would provide the best evaluation of the conversion factor. The objective of the study was to define the soil HT to HTO conversion parameters specific to the Cernavoda NPP site. In June 2016, a series of experiments were conducted to meet this objective. First, the in situ deposition velocity of D2 gas, as a surrogate for HT gas, was obtained using an exposure chamber. Diffusion of D2 into the soil was then evaluated based on the measurements of DHO concentrations in the exposed soil. As soil microbes play a role in the conversion of HT to HTO, this work included a microbiological characterization of the soil, which targeted total soil bacteria (cultivable and gene-based) and hydrogen oxidizing bacteria (cultivable and gene-based). The fraction of hydrogen oxidizing cultivable soil bacteria represented 14–20% of the total cultivable bacteria population estimated as 2.8–29.2 × 105 cfu/g of soil. The empirically derived HT to HTO conversion factor was lower than the default value (4.3%). It fell between 0.9% and 2.0%. The default value is therefore more conservative than the Cernavoda site-specific derived value obtained from the study.

This study presents a polyethylene beads method for OBT determination in animal tissues and animal products for cases where the amount of water recovered by combustion is limited by sample size or quantity. In the method, the amount of water recovered after combustion is enhanced by adding tritium-free polyethylene beads to the sample prior to combustion in an oxygen bomb. The method reduces process time by allowing the combustion water to be easily collected with a pipette. Sufficient water recovery was achieved using the polyethylene beads method when 2 g of dry animal tissue or animal product were combusted with 2 g of polyethylene beads. Correction factors, which account for the dilution due to the combustion water of the beads, are provided for beef, chicken, pork, fish and clams, as well as egg, milk and cheese. The method was tested by comparing its OBT results with those of the conventional method using animal samples collected on the Chalk River Laboratories (CRL) site. The results determined that the polyethylene beads method added no more than 25% uncertainty when appropriate correction factors are used.

Ingestion is one of the most important pathways to consider for calculating tritium dose to human beings. The objective of this study is to determine changes to TFWT and OBT concentrations in food as a result of its preparation for consumption. The contribution of OBT to the total tritium dose can be reduced by the oxidation of OBT during food preparation. The results show that preparation for consumption can result in reductions of up to 46% in TFWT concentration and 54% in OBT concentration in potato, and 22% in TFWT concentration and 57% in OBT concentration in Swiss chard.

The mean expected value of the OBT/HTO ratio (i.e. generic ratio) is derived in this study on the joint basis of a long-term study conducted at Atomic Energy of Canada Limited (AECL)'s Chalk River Laboratories (CRL), model simulations targeted at filling gaps in a yet incomplete timeline of CRL measurements and a reference dataset comprised of numerous experiments reported in the literature. Cultivar variability and disparity in site-specific settings are covered by the reference dataset. Dynamical variability caused by meteorology has been a specific target of the long-term experimental campaign at CRL, where the former two types of variability were eliminated. The distribution of OBT/HTO ratios observed at CRL appears to be a fairly good match to the distribution of OBT/HTO ratios from the literature. This implies that dynamical variability appears important in both cases. Dynamics of atmospheric HTO at CRL is comprised of a sequence of episodes of atmospheric HTO uptake and re-emission of plant HTO. The OBT/HTO ratio appears sensitive to the proportion of the duration of these two episodes: the lesser the frequency (and duration) of plume arrivals, the higher the expected mean OBT/HTO ratio. With the plume arrival frequency defined by the typical wind rose, one would encounter a mean OBT/HTO ratio close to 2. It is important to note that this number is seen both in the reference dataset, and in the continuous timeline of HTO and OBT reconstructed from CRL observations by dynamical interpolation (modelling). Many datasets (including that of CRL) targeted at the OBT/HTO ratio are biased high compared to the suggested number. This could be explained by scarce measurements of the low OBT/HTO ratios in the short phase of uptake of atmospheric HTO by the plant.

The need for a less conservative, but reliable risk assessment of accidental tritium releases is emphasized in the present debate on the nuclear energy future. The development of a standard conceptual model for accidental tritium releases must be based on the process level analysis and the appropriate experimental database. Tritium transfer from atmosphere to plants and the subsequent conversion into organically bound tritium (OBT) strongly depends on the plant characteristics, seasons, and meteorological conditions, which have a large variability. The present study presents an overview of the relevant experimental data for the short term exposure, including the unpublished information, also. Plenty of experimental data is provided for wheat, rice, and soybean and some for potato, bean, cherry tomato, radish, cabbage, and tangerine as well. Tritiated water (HTO) uptake by plants during the daytime and nighttime has an important role in further OBT synthesis. OBT formation in crops depends on the development stage, length, and condition of exposure. OBT translocation to the edible plant parts differs between the crops analyzed. OBT formation during the nighttime is comparable with that during the daytime. The present study is a preliminary step for the development of a robust model of crop contamination after an HTO accidental release.

The objective of this study is to quantify the relative amounts of exchangeable organically bound tritium (OBT) and non-exchangeable OBT in various vegetables. A garden plot at Perch Lake, where tritium levels are slightly elevated due to releases of tritium from a nearby nuclear waste management area and Chalk River Laboratories (CRL) operations, was used to cultivate a variety of vegetables. Five different kinds of vegetables (lettuce, cabbage, tomato, radish and beet) were studied. Exchangeable OBT behaves like tritium in tissue free water in living organisms and, based on past measurements, accounts for about 20% of the total tritium in dehydrated organic materials. In this study, the percentage of the exchangeable OBT was determined to range from 20% to 57% and was found to depend on the type of vegetables as well as the sequence of the plants exposure to HTO.

To improve understanding of environmental tritium behaviour, the International Atomic Energy Agency (IAEA) included a Tritium and C-14 Working Group (WG) in its EMRAS (Environmental Modelling for Radiation Safety) program. One scenario considered by the WG involved the prediction of time-dependent tritium concentrations in freshwater mussels that were subjected to an abrupt increase in ambient tritium levels. The experimental data used in the scenario were obtained from a study in which freshwater Barnes mussels ( Elliptio complanata ) were transplanted from an area with background tritium concentrations to a small Canadian Shield lake that contains elevated tritium. The mussels were then sampled over 88 days, and concentrations of free-water tritium (HTO) and organically-bound tritium (OBT) were measured in the soft tissues to follow the build-up of tritium in the mussels over time. The HTO concentration in the mussels reached steady state with the concentration in lake water within one or two hours. Most models predicted a longer time (up to a few days) to equilibrium. All models under-predicted the OBT concentration in the mussels one hour after transplantation, but over-predicted the rate of OBT formation over the next 24 h. Subsequent dynamics were not well modelled, although all participants predicted OBT concentrations that were within a factor of three of the observation at the end of the study period. The concentration at the final time point was over-predicted by all but one of the models. The relatively low observed concentration at this time was likely due to the loss of OBT by mussels during reproduction.

We report on a CDF measurement of the total cross section and rapidity distribution, d{sigma}/dy, for q{bar q} {yields} {gamma}{sup *}/Z {yields} e{sup +} e {sup -} events in the Z boson mass region (66 < M {sub ee} < 116 GeV/c {sub 2}) produced in p{bar p} collisions at {radical}s = 1.96 TeV with 2.1 fb{sup -1} of integrated luminosity. The measured cross section of 257 {+-} 16pb and d{sigma}/dy distribution are compared with Next-to-Leading-Order (NLO) and Next-to-Next-to-Leading-Order (NNLO) QCD theory predictions with CTEQ and MRST/MSTW parton distribution functions (PDFs). There is good agreement between the experimental total cross section and d{sigma}/dy measurements with theoretical calcualtion with the most recent NNLO PDFs.

By using observations from the Aerosol Robotic Network (AERONET), aerosol types are classified according to dominant size mode and radiation absorptivity as determined by fine-mode fraction (FMF) and single-scattering albedo (SSA), respectively. The aerosol type from anthropogenic sources is significantly different with regard to location and season, while dust aerosol is observed persistently over North Africa and the Arabian Peninsula. For four reference locations where different aerosol types are observed, time series and optical properties for each aerosol type are investigated. The results show that aerosol types are strongly affected by their sources and partly affected by relative humidity. The analysis and methodology of this study can be used to compare aerosol classification results from satellite and chemical transport models, as well as to analyze aerosol characteristics on a global scale over land for which satellite observations need to be improved.

A high performance distillation system to remove krypton from xenon was constructed, and a purity level of Kr/Xe = $\sim 3 \times 10^{-12}$ was achieved. This development is crucial in facilitating high sensitivity low background experiments such as the search for dark matter in the universe., Comment: 15 pages, 11 figures

This paper presents detailed facies and architectural analyses and palaeoenvironmental reconstruction of the Sihwa Formation (Lower Cretaceous), mid-west Korea, which comprises an about 3-km-thick non-marine succession containing abundant dinosaur eggshells. Based on constituent facies, bedset geometry, stacking pattern, and bounding surface characteristics, the entire succession can be classified into three architectural elements. Element I occurs along the basin margin and shows a monotonous stacking of tabular or crudely stratified conglomeratic units. It represents alluvial-fan deposits of debris-flow-dominated fan and sheetflood-dominated fan. Element II is characterized by multi-storey, sheet or upward-widening, conglomeratic channel-fills whose maximum thickness exceeds 1.5 m. Each channel-fill unit is encased within red–brown silty sandstones of Element III with sharp erosional bases but diffuse gradational upper boundaries. It consists generally of (1) cut-and-fill deposit (trough cross-stratified or openwork conglomerate) in the lower part and (2) composite low-relief bar deposit (lenticular conglomerate and stratified gravelly sandstone) in the upper part. Shallowness of each cut-and-fill unit, absence of fining-upward lateral accretion package and the predominance of simple-bar deposit collectively suggest deposition from ephemeral braided streams. Element III typically shows a fining-upward stacking of (1) single- or multi-storey small-scale ( The entire sequence of the Sihwa Formation can be divided into the alluvial-fan and terminal-fan successions. The alluvial-fan succession displays a progradational stacking pattern and indicates a low rate of basin subsidence in the initial phase of rifting. The upper terminal-fan succession consists of proximal braided stream and distal floodplain deposits in the western and central parts of the basin and is characterized by an axial dispersal pattern and an aggradational stacking. It suggests rapid subsidence of the basin floor during the main phase of rifting. The asymmetrical cross-basin distribution of each architectural element reflects a half-graben structure of the basin with steep-gradient fault-bounded eastern margin (footwall block) and gently sloped, flexural western margin (hangingwall block). The predominance of ephemeral braided-stream deposits along with red–brown fine-grained floodplain deposits with common calcretes indicates arid to semi-arid palaeoclimates. Approximately 140 dinosaur eggs (Faveoloolithidae and Dendroolithidae) were identified mainly from the (gravelly) siltstones and small-scale channel fills of Element III deposits and partly from the cut-and-fill conglomerates of Element II deposits. The eggs commonly retain their original oval shape but are invariably breached and stuffed with the substrate of gravels and silt. They are either isolated or clustered, forming a circular concentration in plan view. The abundant yield of eggs, more than 20 eggs in 5 separate nests from a single depositional unit, suggests a dense population of the parental dinosaurs. The repetitive occurrence in many stratigraphic horizons reflects site preference as a nesting habitat of the near-channel or abandoned channel areas.

To assess the efficacy and safety of covered retrievable nitinol stents in oesophageal cancer patients with airway involvement.Under fluoroscopic guidance, covered retrievable nitinol airway stents were placed in 23 oesophageal cancer patients with airway stricture and/or oesophagorespiratory fistula (ERF) over a long period of 12 years. Six patients only had aspiration by ERF and three patients had both airway stricture and asymptomatic ERF. Technical aspects, dyspnoea improvement, and/or resolution of ERF symptoms, complications, reinterventions, and survival data were evaluated.A total of 27 airway stents (14 tracheal, 11 bronchial, and two hinged) were placed successfully in 23 patients with airway stricture or ERF. Dyspnoea score decreased significantly after stent placement (p0.001). ERF were sealed off in all nine patients. Complications included stent migration or expectoration (n=4), haemoptysis (n=2), sputum retention (n=7), and tumour overgrowth (n=1). All three migrated stents were easily removed. Twenty-one patients died, with the median survival period of 76 days (range 2-197 days).Placement of covered retrievable expandable nitinol stents was safe and effective for the palliative treatment of airway strictures and/or ERF, with a reasonable range of complications, in patients with advanced oesophageal cancer.

The International Atomic Energy Agency (IAEA)'s Environmental Modelling for Radiation Safety (EMRAS) model evaluation programme includes a Tritium and Carbon-14 Working Group (TCWG), the goal of which is to test the performance of models for the environmental transfer. This paper describes work on two of the nine TCWG scenarios; one involved the prediction of time-dependent tritium concentrations in freshwater mussels subject to an abrupt change in ambient tritium levels and the second was concerned with the prediction of carbon-14 concentrations in rice grown in the vicinity of sources of continuous atmospheric releases.

The intensity of scintillation light emission from liquid xenon at room temperature was measured. The scintillation light yield at 1 deg. was measured to be 0.64 +/- 0.02 (stat.) +/- 0.06 (sys.) of that at -100 deg. Using the reported light yield at -100 deg. (46 photons/keV), the measured light yield at 1 deg. corresponds to 29 photons/keV. This result shows that liquid xenon scintillator gives high light yield even at room temperature., Comment: 16pages,12figures

An experimental study was performed to investigate the pool boiling critical heat flux (CHF) in one-dimensional inclined rectangular channels by changing the orientation of a copper test heater assembly. In a pool of saturated water under the atmospheric pressure, the test parameters included the gap sizes of 1, 2, 5, and 10 mm, and the surface orientation angles from the downward-facing position (180°) to the vertical position (90°). Tests were conducted on the basis of the visualization of boiling phenomena in the narrowly confined channel and open periphery utilizing a high-speed digital camera. To prevent the heat loss from the water pool and copper test heater, a state-of-the-art vacuum pumping technique was introduced. It was observed that the CHF generally decreased as the surface inclination angle increased and as the gap size decreased. In the downward-facing position (180°), however, the vapor movement was enhanced by the gap structure, which produced the opposing result; that is, the CHF increased as the gap size decreased. Phenomenological characteristics regarding the interfacial instability of vapor layer were addressed in terms of visualization approaching the CHF. It was found that there exists a transition angle, around which the CHF changes with a rapid slope.

Y2−xGdxO3/Eu3+ thin films have been grown on Si (100) substrates using pulsed laser deposition. The films deposited at the different conditions show different microstructural and luminescent characteristics. The crystallinity, surface morphology, and photoluminescence (PL) of the films are highly dependent on the amount of Gd. The PL results obtained from Y2−xGdxO3/Eu3+ films grown under optimized conditions have indicated that Si (100) is a promising substrate for the growth of high-quality Y2−xGdxO3/Eu3+ thin film phosphor. In particular, incorporation of Gd into the Y2O3 lattice can induce a remarkable increase of PL. The highest emission intensity was observed with Y1.35Gd0.60O3/Eu3+, whose brightness was a factor of 1.9 larger than that from Y2O3/Eu3+ films. This phosphor is promising for applications in flat panel displays.

Li-doped Y2O3:Eu3+ luminescent thin films have been grown on Si (100) and Al2O3 (0001) substrates using a pulsed laser deposition technique. The thin film phosphors were deposited by changing the substrates and the processing conditions (substrate temperature and oxygen pressure). The films grown under different deposition conditions have been characterized using microstructural and luminescent measurements. The PL intensity of the Li-doped Y2O3:Eu3+ films are highly dependent on the crystallinity and surface roughness of the films. The films are uniaxially textured in both Si (100) and Al2O3 (0001) cases and the films grown on Al2O3 (0001) substrate exhibit the superior crystallization and photoluminescent properties. The brightness of the films grown on Al2O3 (0001) substrate was increased by a factor of 2.1 in comparison with that of the films grown on Si (100) substrate. The photoluminescence intensity and surface roughness have similar behavior as a function of not only oxygen pressure but also substrate temperature. This phosphor may promise for application to the flat panel displays.

Y 2− x Gd x O 3 :Eu 3+ phosphor thin films were grown on Si (1 0 0) and Al 2 O 3 (0 0 0 1) substrates using a pulsed laser deposition (PLD) technique. Thin film phosphors were deposited by changing the substrates and the processing conditions (substrate temperature and oxygen pressure). The films grown under different deposition conditions have been characterized using microstructural and luminescent measurements. The photoluminescence (PL) brightness data obtained from the Y 2− x Gd x O 3 :Eu 3+ films grown under optimized conditions have indicated that Al 2 O 3 (0 0 0 1) and Si (1 0 0) substrates are promising substrate for the growth of high quality Y 2− x Gd x O 3 :Eu 3+ thin film red phosphor. The films were preferentially (2 2 2) oriented in both Si (1 0 0) and Al 2 O 3 (0 0 0 1) cases and the films grown on Al 2 O 3 (0 0 0 1) substrate exhibit the superior crystallization and photoluminescent properties. The highest emission intensity was observed with Y 1.35 Gd 0.6 O 3 :Eu 3+ films grown on Al 2 O 3 (0 0 0 1) substrate, whose brightness increased by a factor of 3.7 in comparison with that of the films grown on Si (1 0 0) substrate. The PL intensity of the Y 2− x Gd x O 3 :Eu 3+ films are highly dependent on the crystallinity and surface roughness of the films. The PL intensity and surface roughness have similar behavior as a function of not only oxygen pressure but also substrate temperature. This phosphor may be promising for application to the flat panel displays.

A Time-of-Flight (TOF) detector, based on plastic scintillators and fine-mesh photomultipliers, has been added to the Collider Detector at Fermilab (CDF)-II experiment at the Tevatron pp collider. The primary physics motivation is to provide charged kaon identification to improve neutral B meson flavor determination. Besides that, the TOF detector found application in the CDF trigger system in implementation of highly ionizing particle, high multiplicity and cosmic rays triggers.

In inhibitor-free 3% Si–Fe alloys containing sulfur, the matter which the final main texture after annealing becomes among the {1 0 0}〈u v w〉, {1 1 0}〈0 0 1〉 and {1 1 0}〈u v w〉 components depends on the combination of various factors: final reduction, heating rate, flow rate of hydrogen and bulk content of sulfur. With increasing final reduction and heating rate, the final main texture after annealing tends to be transited from the {1 1 0}〈u v w〉 to the {1 1 0}〈0 0 1〉 and then followed by the {1 0 0}〈u v w〉 component. This is due to the active surface-energy-induced selective growth of the {1 0 0}〈u v w〉 grains that makes the survival and selective growth of the {1 1 0} grains difficult. On the viewpoints of the nucleation and the selective growth, a higher flow rate of hydrogen and a lower bulk content of sulfur may result in the transition in final main texture of the {1 0 0}〈u v w〉 to the {1 1 0}〈0 0 1〉 and subsequently to the {1 1 0}〈u v w〉 component after annealing.

The present study systematically compares the Mellor–Yamada (MY) model and the k−e algebraic stress model in order to verify the possibility of using the k−e algebraic stress model in atmospheric applications. The results of the parameterization process and atmospheric application of both models confirmed that the MY model neglected the pressure redistribution effect of buoyancy due to 〈uiuj〉 and 〈uiθ〉 and that of shear due to 〈uiθ〉. In addition, the MY model overestimated the turbulent energy dissipation. Based on the formulation of the k−e algebraic stress model, we modified the constant value Cμ(=0.09) in the standard k−e model to obtain the variables CμM and CμH to account for atmospheric stability. Finally, the results of the simulation obtained from the Wangara experiment verify the possibility of using the k−e algebraic stress model in atmospheric application.

The K2K long-baseline neutrino oscillation experiment uses a Scintillating Fiber Detector (SciFi) to reconstruct charged particles produced in neutrino interactions in the near detector. We describe the track reconstruction algorithm and the performance of the SciFi after three years of operation., Comment: 24pages,18 figures, and 1 table. Preprint submitted to NIM

ZnGa 2 O 4 thin film phosphors have been deposited using a pulsed laser deposition technique on Si(100) substrates at a substrate temperature of 550 °C with various oxygen pressures and post-annealing temperatures. The structural characterization was carried out on a series of ZnGa 2 O 4 films grown at an oxygen pressure range of 50–300 mTorr, and subsequently post-annealed at 600 and 700 °C. The optimum oxygen pressure for luminescent characteristics was about 100 mTorr. The luminescent spectra show a broad band extending from 350 to 600 nm peaking at 460 nm. A post-annealing treatment of ZnGa 2 O 4 thin films led to the different shape of luminescent intensity and grain size. β-Ga 2 O 3 phase appeared at an annealing temperature of 600 °C and increased with increasing annealing temperature. We have also investigated the effect of the ligand field strength on the resultant energy levels for ZnGa 2 O 4 thin film phosphor. The annealing process at different temperatures may lead to different dominant emissions.

The KEK to Kamioka long-baseline neutrino experiment (K2K) has begun its investigation of neutrino oscillations suggested by atmospheric neutrino observations. Twenty-eight neutrino events have been detected in coincidence with the expected arrival time of the beam in the 22.5 kt fiducial volume of Super--Kamiokande, the far detector at 250 km distance. The expectation is 37.8+3.5-3.8, derived using measurements of neutrino interactions in a near detector and extrapolation using a beam simulation validated by a measurement of pion kinematics after production and focusing. The background is of order 10^-3 events., Comment: 6 pages, 3 embedded figures, LaTeX with RevTeX style, submitted to PRL. This version is As Submitted

In order to study the incorporation into organically bound tritium (OBT) of HTO deposited onto a paddy field during the growing season of rice, a solution of HTO was applied to the water surface of the culture box in a greenhouse 1 d before, and at 5 different times after, transplanting rice seedlings. The OBT concentration in the mature plant varied with the application time by factors of 5–25 depending on plant parts. Soil-to-plant transfer factors (m 2 kg −1 -dry) of HTO for OBT in straw and hulled seed were in the ranges 4.0×10 −5 – 2.1×10 −4 and 1.3×10 −5 – 3.3×10 −4 , respectively. The highest was achieved at the application time when each part grew most actively. Mixing HTO with the topsoil tended to increase OBT production. The HTO concentration in percolating water reached its maximum 10–25 d after each application and then decreased slowly. The fractions of applied HTO that were leached out of the boxes were 8.0–28.4% depending on application times. One week after harvest, the depth profile of HTO in the top 30 cm of soil was investigated showing that less than 4% of applied HTO remained there. It was estimated that 70–90% of applied HTO escaped to the air via evapotranspiration.

Effects of pre-annealing and hydrogen flow rate on final texture and magnetic induction have been investigated in inhibitor-free 100 μm thick 3% Si–Fe strips containing 18 ppm sulfur. Without any pre-annealing, the strip showed a low magnetic induction, due to various {1 1 0}, {1 0 0} and {1 1 1} final texture components. The number and the area fraction of {1 1 0} grains increased with increasing pre-annealing temperature and hydrogen flow rate. A pre-annealing temperature range that results in the sharp {1 1 0} 〈0 0 1〉 texture is observed, depending on the hydrogen flow rate.

This paper presents cold-rolling and annealing methods to obtain a high-magnetic induction in inhibitor-free 0.1-mm-thick 3% silicon–iron sheets containing 18 or 150 ppm sulfur. In case of the two-step cold-rolling, the sheets containing 150 ppm sulfur showed a strong {1 0 0} final texture at 400 °C/h, and some fraction of {1 1 0} component was observed at 25 °C/h. However, three-step cold-rolling resulted in a sharp {1 1 0}〈0 0 1〉 final texture at 25 °C/h. This is due to the difference in intensity ratio of {1 0 0}〈0 1 1〉 to {1 1 1}〈1 1 2〉 in the cold-rolling texture which influences the nucleation of {1 1 0}〈0 0 1〉 component and the selective growth kinetics of various grains. In case of 18 ppm sulfur, the final texture was mainly composed of a sharp {1 1 0}〈0 0 1〉 component even at 400 °C/h, due to the relatively low segregation concentration.

From an exposure of 25.5~kiloton-years of the Super-Kamiokande detector, 900 muon-like and 983 electron-like single-ring atmospheric neutrino interactions were detected with momentum $p_e > 100$ MeV/$c$, $p_\mu > 200$ MeV/$c$, and with visible energy less than 1.33 GeV. Using a detailed Monte Carlo simulation, the ratio $(\mu/e)_{DATA}/(\mu/e)_{MC}$ was measured to be $0.61 \pm 0.03(stat.) \pm 0.05(sys.)$, consistent with previous results from the Kamiokande, IMB and Soudan-2 experiments, and smaller than expected from theoretical models of atmospheric neutrino production.

Experiments have been carried out in order to visualize the behaviour of a two-phase flow inside a hemispherical narrow gap. The test facility consists of a hemispherical heater and a pyrex-glass bell-jar-shaped vessel. The transparent pyrex-glass vessel was intended to make a 1mm gap between the heater and itself but the gap size was not uniform because of manufacturing difficulties. The incoming water and escaping steam flowed in counter-directions through separated flow paths. As the heater power increased, the escaping steam velocity increased and finally reached the counter-current flow limit(CCFL). The CCFL occurred at the location where the top-end gap size is smaller compared to the other part. Just below the top-end where the CCFL occurred, the heater surface was found to be locally dried out.

We present the results of experimental studies of hadron showers in a copper/quartz-fiber calorimeter, based on the detection of Cherenkov light. These studies show that there are very significant differences between the signals from protons and pions at the same energies. In the energy range between 200 and 375GeV, where these studies were performed, the calorimeter's response to protons was typically 10% smaller than the response to pions. On the other hand, the energy resolution was about 25% better for protons. In addition, the protons had a Gaussian line shape, whereas the pion response curve was asymmetric. These differences can be understood from the requirements of baryon number conservation in the shower development. They are expected to be present in any non-compensating calorimeter, to a degree determined by the e/h value. © 1998 Elsevier Science B.V. All rights reserved. Comisión Interministerial de Ciencia y Tecnología: AEN96-2051-E CERN Russian Foundation for Basic Research 95-02-04815 Országos Tudományos Kutatási Alapprogramok: T 016823 TBAG1590 International Foundation for Science: M82000, M82300 We would like to thank our colleagues from CMS, and in particular J. Bourotte and M. Haguenauer, who made the described beam tests possible. We are grateful to N. Doble, who provided us with particle beams of excellent quality. This project was carried out with financial support from CERN, the US Department of Energy, RMKI-KFKI (Hungary, OTKA grant T 016823), the Scientific and Technical Research Council of Turkey (TÜBITAK, grant TBAG1590), CICYT (Spain, grant AEN96-2051-E), the International Science Foundation (grants M82000 and M82300), the State Committee of the Russian Federation for Science and Technologies, and the Russian Research Foundation (grant 95-02-04815).

We present test-beam data analysis of a quartzfibre calorimeter prototype composed of a single active section with a passive absorber in front of it. The partial suppression of the electromagnetic showers leads to the equalization of the response to electrons and pions for a given depth of this passive section. Results are compared with the Monte-Carlo expectations. Russian Foundation for Basic Research Ministry of Education and Science of the Russian Federation Comisión Interministerial de Ciencia y Tecnología: AEN96-205 1-E Országos Tudományos Kutatási Alapprogramok: T 0 16823 95-02-04815 CERN M82300, 82000 This project was carried out with financial support from CERN, the US Departmento f Energy, RMKI-KFKI (Hungary, OTKA grant T 0 16823),T UBITAK (Turkey), CICYT (Spain, grant AEN96-205 1-E), the InternationalS cience Foundation (grantsM 82000 and M82300), the Ministry of the Russian Federation for Science and Technology, and the Russian Research Foundation (grant 95-02-04815).

We present the results of beam tests with high-energy (8-375 GeV) electrons, pions, protons and muons of a sampling calorimeter based on the detection of Cherenkov light produced by shower particles. The detector, a prototype for the very forward calorimeters in the CMS experiment, consists of thin quartz fibers embedded in a copper matrix. Results are given on the light yield of this device, on its energy resolution for electron and hadron detection, and on the signal uniformity and linearity. The signal generation mechanism gives this type of detector unique properties, especially for the detection of hadron showers: narrow, shallow shower profiles and extremely fast signals. These specific properties were measured in detail. The implications for measurements in the high-rate, high-radiation Large Hadron Collider (LHC) environment are discussed. G rant9 5-02-04185 82000a, M82300 Comisión Interministerial de Ciencia y Tecnología: AEN96-2051-E CERN GrantT 016823 We wouldl ike to thanko ur colleaguefsr om CMS, and, in particularJ,. Bourottea nd M. Haguenauer, who made the describedb eamt estsp ossible.W e are gratefutl o N. Doble,w ho providedu s with particle beamso f excellentq uality.This project was carriedo ut with financials upportf rom CERN, the U.S. Departmenotf Energy,R MKI-KFKI (Hungary, OTKA GrantT 016823)t,h eS cientifica ndT echnical ResearchC ouncil of Turkey (TUBITAK), CICYT (Spain, Grant AEN96-2051-E), the International ScienceF oundation( grantsM 82000a nd M82300), the StateC ommitteeo f the RussianF ederationfo r Sciencea ndT echnologiesa, ndt heR ussianR esearch Foundation(G rant9 5-02-04185 ).

The Cretaceous Uhangri Formation, southwest Korea, is a lacustrine sequence surrounded by acidic volcanic terrain and comprises sandstone/chert and laminated chert/black shale couplets in the upper part. In both cases, the Uhangri chert is composed mainly of SiO 2 (74–81%), Al 2 O 3 (10–12%) and K 2 O (6–7%). Its impure nature is largely due to the presence of feldspar grains and clays within a microcrystalline quartz matrix. The Uhangri chert is characterized by common soft-sediment deformation, in-situ brecciation, slumping and no organic traces, which collectively indicate its inorganic origin. The sandstone/chert couplets are alternations of massive, graded, crudely stratified, rippled, or ripple-cross-laminated sandstone layers and generally homogeneous chert layers. The laminated chert/black shale couplets consist of alternating light- and dark-coloured laminae of chert, and overlying black shale. These couplets were most likely deposited by episodic riverine inflows into a silica-rich alkaline lake. The freshwater input could trigger direct inorganic silica precipitation through an abrupt decrease in lake-water pH. The sandstone/chert couplets would be deposited by high-density underflows, whereas the laminated chert/black shale couplets by fine-sediment dominant overflows.

Gate oxide integrity (GOI) tests, surface photovoltage and deep level transient spectroscopy of Czochralski silicon wafers reveal oxide degradation at heavy precipitation, defect-controlled recombination lifetime and defect-induced deep levels. Electron beam induced current measurements on those wafers before and after intentional metal decoration reveal relatively shallow levels in the non-decorated state and deep levels in the decorated state. It is shown that the actual contamination level determines the usefulness of GOI tests for predicting material performance in device processing.

The Kyokpori Formation (Late Cretaceous), southwestern Korea, consists largely of siliciclastic sediments deposited in lacustrine basin. The formation (ca. 500 m thick) shows two fining-upward successions, with its lowermost part (ca. 50 m thick) dominated by bouldery conglomerates and outsize-clast-bearing sandstones. The bouldery conglomerates are either disorganized, normally graded, inversely graded, or crudely stratified with common abrupt lateral facies changes, and characterized by a poorly sorted coarse-grained matrix, abundant outsized and/or protruding clasts and a significant correlation (r = 0.78) between maximum particle size (up to 2 m) and bed thickness (generally < 60 cm). These features collectively suggest cohesionless debris flows. The abrupt lateral facies change may originate from either (1) freezing of the entire flow to retain a heterogeneous rheology, similar to a multiple-plug flow, or (2) deposition of a laterally migrating, pulsatory flow with differing rheodynamics from head to tail. The outsize-clast-bearing sandstones are either stratified or thin bedded with alternation of massive/inversely graded and laminated layers. Each bed consists of moderately to well sorted, fine to coarse sandstone, with pebble- to boulder-grade, outsized clasts which are larger than the layer thickness (2–10 cm). The outsized clasts are randomly scattered within the sandstoe beds, occassionally forming clusters. These features suggest dual transport mechanisms, i.e., density flows for the sandstone beds per se and debris falls for the outsized clasts. Both the occurence of debris-fall deposits and the high “relative competence” (MPSBTh = 0.74) of debris-flow deposits suggest a steep slope upon which sediments can gain high downslope mobility overcoming the frictional resistance of substratum. The depositional slope angle is inferred to be about 5–17°, based on the properties of debris-flow deposits: flow thickness is assumed to be similar to bed thickness and debris strength is estimated as 103–104 dyn/cm2, using the parameters of protruding clasts. The steep gradient probably developed on a delta slope off a valley mouth.

Cores made of Fe 77 B 16 Si 5 Cr 2 amorphous ribbons were annealed in a high frequency induction field. This field provided heat and generated an alternating magnetic flux in the cores. The optimum temperature and duration of induction annealing were even lower and shorter than those in conventional field annealing. The soft magnetic properties of the induction annealed cores were better than those of the as-quenched amorphous alloys. At the same time, the induction annealed amorphous ribbon shows a higher fracture stress than conventionally annealed samples.

The CDF II detector contains a time-of-flight detector consisting of 216 scintillator bars of 279 cm length and 4×4 cm2 cross-section located at a radius of 138 cm from the beam axis. The bars are installed on the inner surface of the CDF solenoid, which produces an axial field of 1.4 T. Nineteen-stage fine-mesh photomultiplier tubes are attached at both ends of the scintillator bars. Photostatistics limit the time-of-flight resolution, which is expected to be 100 ps. The primary physics motivation is K± identification for improved neutral B meson flavor determination.

We report our first successful ultrafast electron diffraction from beams of isolated molecules, CCI_4, I_2, and CF_3I. To demonstrate the feasibility of studying reactions, we report results on the structure of CF_3 radical from the dissociation of CF_3I.