scholarly journals Evaluation of tritium retention in plasma facing components during JET tritium operations

2021 ◽  
Author(s):  
Anna Widdowson ◽  
J. Paul Coad ◽  
Yevhen Zayachuk ◽  
Ionut Jepu ◽  
Eduardo Alves ◽  
...  
Keyword(s):  
Accumulation Rate ◽  
Ex Situ ◽  
Retention Data ◽  
Operating Period ◽  
Data Set ◽  
Plasma Facing Components

Abstract An assessment of the tritium (T) inventory in plasma facing components (PFC) during JET T & DT operations is presented based on the most comprehensive ex-situ fuel retention data set on JET PFCs from the 2015-2016 ILW3 operating period is presented. The global fuel retention is 4.19 x 1023 D atoms, 0.19% of injected fuel. The inner divertor remains the region of highest fuel retention (46.5%). The T inventory in PFCs at the end of JET operations is calculated as 7.48 x 1022 atoms and is informative for accountancy, clean-up efficacy and waste liability assessments. The T accumulation rate at the upper inner divertor during JET deuterium-tritium (DT) operations has been used to assess the requirements and frequency of operation of a new laser induced desorption diagnostic to be installed on JET for the final DT experiments in 2023.

scholarly journals Measuring and Estimating Pressure-Saturation Curves on Undisturbed Soil Samples by Using Water and NAPL

2002 ◽  
Vol 51 (1-2) ◽  
pp. 27-36 ◽  
Author(s):  
Csaba Makó
Keyword(s):  
Humus Content ◽  
Estimation Method ◽  
Soil Samples ◽  
Direct Result ◽  
Organic Liquids ◽  
Soil Parameters ◽  
Retention Data ◽  
Data Set ◽  
Undisturbed Soil ◽  
In Series

In order to expand the experimental data set of models describing the movement of organic liquids polluting the soils, a series of experiments was set up in which the fluid retention (pressure- s aturation curves of the soils) were measured using water and NAPL (DUNASOL 180/220, a non aromatic petroleum product). Measurements were carried out on undisturbed soil samples originating from 35 different horizons of 12 characteristic Hungarian soils. The P-S curves with NAPL were determined in series, by a modified pressure cell apparatus - designed and constructed in the laboratory of our department - containing oil-resistant (silicon rubber, Teflon) components.   The applied methodology and the statistical analysis of the measured data are presented. The results show that the commonly used Leverett-type scaling of the water retention data provides inadequate estimation of the NAPL retention in some cases. This deviation may be a direct result of changes in clay volume and soil aggregation when saturation with different fluids was performed.  According to the analysis, however, with the easily measurable soil parameters (bulk density, particle size distribution and humus content) a better estimation of NAPL retention can be given. This estimation method (after extending the database) can be useful for modelling the fate and migration of NAPL or mapping the organic contaminant sensitivity of the soils. 

scholarly journals Ex situ analysis of W7-X divertor plasma-facing components by picosecond laser diagnostics

2020 ◽  
Vol T171 ◽  
pp. 014018 ◽  
Author(s):  
D Zhao ◽  
R Yi ◽  
J Oelmann ◽  
S Brezinsek ◽  
M Rasinski ◽  
...  
Keyword(s):  
Laser Diagnostics ◽  
Picosecond Laser ◽  
Ex Situ ◽  
Plasma Facing Components

Dual Threshold Analysis and its Tuning Tool Development for Leak Detection

2014 ◽  
Author(s):  
Jianping Gao ◽  
Mike Chen
Keyword(s):  
Steady State ◽  
Real Time ◽  
Design Process ◽  
Detection System ◽  
Leak Detection ◽  
Tool Development ◽  
Operating Period ◽  
Data Set ◽  
Threshold Setting ◽  
Threshold Tuning

Dual threshold setting in CPM (Computational Pipeline Monitoring) systems is a concept to apply two kind of thresholds, namely steady state threshold and transient threshold setting to improve sensitivity during steady state operating period and reduce false alarm rate during transient operating period. Dual threshold implementation in CPM systems is not a trivial task since a real time pipeline may go through very complicated hydraulic scenarios. During design phase of dual threshold, the data set evaluated needs to cover on operational scenario long enough to represent the typical operation of the pipeline. The design process needs to include the design of transient/steady state switching, transient and steady state threshold, waiting time etc and tuning of those design parameter to achieve the optima. This calls for effective analysis to ensure its validity and a tuning tool development with user-friendly graphical user interface (GUI) to facilitate the tuning efforts from leak detection engineers. This paper details the process from dual threshold design and analysis to tuning tool development and application of the tool in real time CPM systems. At first, the concept of dual threshold and its design process being employed in CPM systems are reviewed; Secondly the paper discusses an analysis approach in testing and evaluation of dual threshold design in current CPM systems with identification of room for improvement. Next, the paper elaborates the design and development of a dual threshold tuning tool to simplify the process with intensive application of the tool during the threshold tuning of real time CPM systems to improve the detectability of the current leak detection system, finally concludes with some closing remarks.

scholarly journals Studying Unimodal, Bimodal, PDI and Bimodal-PDI Variants of Multiple Soil Water Retention Models: II. Evaluation of Parametric Pedotransfer Functions Against Direct Fits

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 896 ◽  
Author(s):  
Amir Haghverdi ◽  
Hasan Sabri Öztürk ◽  
Wolfgang Durner
Keyword(s):  
Water Content ◽  
Soil Water ◽  
Water Retention ◽  
Organic Matter Content ◽  
Pedotransfer Functions ◽  
Model Parameters ◽  
Retention Data ◽  
Soil Water Retention ◽  
Data Set ◽  
Free Parameters

A high-resolution soil water retention data set (81 repacked soil samples with 7729 observations) measured by the HYPROP system was used to develop and evaluate the performance of regression parametric pedotransfer functions (PTFs). A total of sixteen soil hydraulic models were evaluated including five unimodal water retention expressions of Brooks and Corey (BC model), Fredlund and Xing (FX model), Kosugi (K model), van Genuchten with four free parameters (VG model) and van Genuchten with five free parameters (VGm model). In addition, eleven bimodal, Peters–Durner–Iden (PDI) and bimodal-PDI variants of the original expressions were studied. Six modeling scenarios (S1 to S6) were examined with different combinations of the following input predictors: soil texture (percentages of sand, silt and clay), soil bulk density, organic matter content, percent of stable aggregates and saturated water content (θs). Although a majority of the model parameters showed low correlations with basic soil properties, most of the parametric PTFs provided reasonable water content estimations. The VGm parametric PTF with an RMSE of 0.034 cm3 cm−3 was the best PTF when all input predictors were considered. When averaged across modeling scenarios, the PDI variant of the K model with an RMSE of 0.045 cm3 cm−3 showed the highest performance. The best performance of all models occurred at S6 when θs was considered as an additional input predictor. The second-best performance for 11 out of the 16 models belonged to S1 with soil textural components as the only inputs. Our results do not recommend the development of parametric PTFs using bimodal variants because of their poor performance, which is attributed to their high number of free parameters.

scholarly journals Planning tiger recovery: Understanding intraspecific variation for effective conservation

2015 ◽  
Vol 1 (5) ◽  
pp. e1400175 ◽  
Author(s):  
Andreas Wilting ◽  
Alexandre Courtiol ◽  
Per Christiansen ◽  
Jürgen Niedballa ◽  
Anne K. Scharf ◽  
...  
Keyword(s):  
Captive Breeding ◽  
Conservation Management ◽  
Scientific Evidence ◽  
Population Decline ◽  
Ex Situ ◽  
Panthera Tigris ◽  
Multiple Trait ◽  
Data Set ◽  
Management Units ◽  
Tiger Conservation

Although significantly more money is spent on the conservation of tigers than on any other threatened species, today only 3200 to 3600 tigers roam the forests of Asia, occupying only 7% of their historical range. Despite the global significance of and interest in tiger conservation, global approaches to plan tiger recovery are partly impeded by the lack of a consensus on the number of tiger subspecies or management units, because a comprehensive analysis of tiger variation is lacking. We analyzed variation among all nine putative tiger subspecies, using extensive data sets of several traits [morphological (craniodental and pelage), ecological, molecular]. Our analyses revealed little variation and large overlaps in each trait among putative subspecies, and molecular data showed extremely low diversity because of a severe Late Pleistocene population decline. Our results support recognition of only two subspecies: the Sunda tiger,Panthera tigris sondaica,and the continental tiger,Panthera tigris tigris, which consists of two (northern and southern) management units. Conservation management programs, such as captive breeding, reintroduction initiatives, or trans-boundary projects, rely on a durable, consistent characterization of subspecies as taxonomic units, defined by robust multiple lines of scientific evidence rather than single traits or ad hoc descriptions of one or few specimens. Our multiple-trait data set supports a fundamental rethinking of the conventional tiger taxonomy paradigm, which will have profound implications for the management of in situ and ex situ tiger populations and boost conservation efforts by facilitating a pragmatic approach to tiger conservation management worldwide.

A soot prediction for a taxi cycle of a diesel engine

2008 ◽  
Vol 222 (10) ◽  
pp. 1879-1881
Author(s):  
A A Stotsky
Keyword(s):  
Steady State ◽  
Diesel Engine ◽  
Accumulation Rate ◽  
New Method ◽  
Engine Test ◽  
Data Set ◽  
Model Based ◽  
Selection Of ◽  
Made In

The time and cost associated with running long-term tests to acquire data on the soot percentage in the oil of a diesel engine necessitate the development of a new method for a model-based prediction of the soot accumulation performance. A new method for a model-based prediction of the soot percentage for a vehicle that sequentially executes a number of taxi cycles is proposed. The method is based on the steady-state soot accumulation rate measurements that are made in the engine test cell, and is used for a relative soot percentage judgement and selection of the most suitable data set among several candidates. The method provides significant savings with respect to the direct long-term soot percentage measurements on a vehicle.

Rates of Sediment Accumulation in Pollen Cores from Small Lakes and Mires of Eastern North America

1988 ◽  
Vol 30 (3) ◽  
pp. 284-297 ◽  
Author(s):  
Robert Stabler Webb ◽  
Thompson Webb
Keyword(s):  
North America ◽  
Accumulation Rate ◽  
Sediment Cores ◽  
Sediment Accumulation ◽  
Linear Interpolation ◽  
Climatic Conditions ◽  
Eastern North America ◽  
Small Lakes ◽  
Data Set ◽  
Depositional Processes

Data from 291 small lakes and mires in eastern North America provide information on the natural variability of rates of sediment accumulation in these environments over the last 18,000 yr. Accumulation rates were calculated by linear interpolation between radiocarbon and biostratigraphic dates from sediment cores taken for pollen analysis. Within the data set, the rates were lognormally distributed with a mean accumulation rate of 91 cm/103 yr, and a range from less than 1 to over 3500 cm/103 yr. The accumulation rate data were divided into five subsets that were temporally or spatially distinct and therefore represent different geomorphic and climatic conditions at the time of deposition. Sediments deposited in basins north of 50°N, south of 40°N, and before 10,000 yr B.P. accumulated at much slower rates than sediments accumulating in midlatitude basins (between 40° and 50°N) between 10,000 and 330 yr B.P. Sediment accumulation over the last 330 yr has, on average, been at rates four to five times faster than any time previously. Inorganic sediments that could be radiocarbon-dated have accumulated at significantly lower rates than organic sediments, reflecting differences in depositional processes. For midlatitude basins during the Holocene, the most likely rate of continuous sediment accumulation within our data set is 65 cm/103 yr. Rates below 10 cm/103 yr are likely to be associated with nonconstant processes of sediment accumulation.

scholarly journals A 485 year record of atmospheric chloride, nitrate and sulfate: results of chemical analysis of ice cores from Dyer Plateau, Antarctic Peninsula

1995 ◽  
Vol 21 ◽  
pp. 182-188 ◽  
Author(s):  
Jihong Cole Dai ◽  
Lonnie G. Thompson ◽  
Ellen Mosley-Thompson
Keyword(s):  
Sea Water ◽  
Accumulation Rate ◽  
Linear Regression Analysis ◽  
Ice Core ◽  
Ice Cores ◽  
Snow Accumulation ◽  
Sea Salt ◽  
Volcanic Emissions ◽  
Data Set ◽  
Snow Chemistry

Detailed ionic analyses of Dyer Plateau snow show that major soluble impurities in snow consist of sodium (Na+), chloride (Cl−), nitrate (NO3−), sulfate (SO42−), and acidity (H+). The ratios of Na+ to Cl− concentrations are close to that of sea water, indicating little or no fractionation of sea-salt aerosols. The analyses of core sections from three sites along a 10 km transect show that local spatial variation of snow chemistry in this area is minimal and that temporal (decadal, inter-annual and sub-annual) variations in snow chemistry are very well preserved.Anion analyses of the upper 181 m section of two 235 m ice cores yield a data set of 485 years (1505-1989) of annual snow accumulation and fluxes of Cl−, NO3−, and non-sea-salt (nss) SO42−. No significant long-term trends are observed in any of the anion fluxes. This is consistent with other Antarctic ice-core records showing no significant anthropogenic atmospheric pollution in the high southern latitudes. Linear regression analysis shows that Cl− flux is independent of snow-accumulation rate. Significant positive correlations are found between accumulation rate and both NO3− flux and background nss-SO42− flux. These results suggest that dry deposition is primarily responsible for air-to-ground Cl− flux while wet deposition dominates the NO3− and nss-SO42− flux (≥90% and ≥75%, respectively). The nss-S042− fluxes provide a chronology of explosive volcanic emissions reaching the Antarctic region for the past 485 years.

scholarly journals New Analyzing Approaches for In Situ Interdiffusion Experiments to Determine Concentration-Dependent Diffusion Coefficients in Liquid Al–Au

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1772
Author(s):  
Toni Schiller ◽  
Elke Sondermann ◽  
Andreas Meyer
Keyword(s):  
Interdiffusion Coefficient ◽  
Liquid Metals ◽  
Solidification Process ◽  
Ex Situ ◽  
Measured Concentration ◽  
Data Set ◽  
X Ray ◽  
In Situ Data ◽  
Interdiffusion Coefficients

Interdiffusion coefficients are key parameters for the solidification process of liquid alloys. However, the determination of interdiffusion coefficients in liquid metals at high temperatures is a challenging and extensive task, due to a variety of potential systematic errors. In recent years we have developed an X-ray in situ shear cell method for the measurement of interdiffusion coefficients in binary metallic melts. This technique enables the monitoring of the experiment in order to exclude fatal errors. Utilizing X-ray contrast, the method also provides a time-resolved concentration distribution. Such an in situ data set contains significantly more information than ex situ evaluated experiments. Available analyzing strategies do not fully exploit this potential yet. We present three new analyzing approaches that are able to retrieve a concentration-dependent interdiffusion coefficient from only one in situ data set. In that way, larger concentration differences become accessible for an experiment, which considerably decreases efforts. Using simulations, the approaches are checked for robustness. Furthermore, the approaches are run on real in situ data from a binary (0 to 9 at% Au-content) Al–Au alloy at 1000 °C which results in a concentration-dependent interdiffusion coefficient within the measured concentration range.

Late Quaternary climate-driven environmental change in the Larsemann Hills, East Antarctica, multi-proxy evidence from a lake sediment core

2005 ◽  
Vol 64 (1) ◽  
pp. 83-99 ◽  
Author(s):  
Dominic A. Hodgson ◽  
Elie Verleyen ◽  
Koen Sabbe ◽  
Angela H. Squier ◽  
Brendan J. Keely ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Accumulation Rate ◽  
Late Quaternary ◽  
East Antarctica ◽  
Algal Community ◽  
Data Set ◽  
Last Glacial ◽  
Larsemann Hills ◽  
Quaternary Climate ◽  
The Last Glacial

AbstractLittle is known about the response of terrestrial East Antarctica to climate changes during the last glacial–interglacial cycle. Here we present a continuous sediment record from a lake in the Larsemann Hills, situated on a peninsula believed to have been ice-free for at least 40,000 yr. A mutli-proxy data set including geochronology, diatoms, pigments and carbonate stable isotopes indicates warmer and wetter conditions than present in the early part of the record. We interpret this as Marine Isotope Stage 5e after application of a chronological age-depth model and similar ice core evidence. Dry and cold conditions are inferred during the last glacial, with lake-level minima, floristic changes towards a shallow water algal community, and a greater biological receipt of ultraviolet radiation. During the Last Glacial Maximum and Termination I the lake was perennially ice-covered, with minimal snowmelt in the catchment. After ca. 10,500 cal yr B.P., the lake became seasonally moated or ice-free during summer. Despite a low accumulation rate, the sediments document some Holocene environmental changes including neoglacial cooling after ca. 2450 cal yr B.P., and a gradual increase in aridity and salinity to the present.

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