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The VSSA approach has the important advantage over classifying, imaging and counting techniques that it does not involve dispersion protocols. Further, the BET technique as the basis for VSSA determination it is in widespread use, generates low costs and is specified for many commercial materials. Finally, the same equipment allows for a deeper analysis by full isotherm evaluation.
The present deliverable assesses all NanoDefine powders, supplemented by further real-world materials (in total 26 powders), and quantitatively compares the relationship between the median size (by Electron Microscopy – considered as benchmark for the EC nanomaterial definition) vs. the size derived from VSSA. The VSSA method mitigates the challenges of EM to assess the thickness of platelets, but worked as well on fibbers and particles of irregular shapes. A screening strategy is proposed. If applied to the further data from real-world materials as validation set, this screening does achieve a correct classification, leaving only borderline materials for tier 2 assessment.
Nuclear Power Plants have been in operation for ca. 50 years. Based on this experience, non-destructive testing tasks specific to thick and highly reinforced nuclear containment structures have materialized. The performance based Service life extension of existing NPPs also needs a measurement based decision to support continuing the service of the concrete part of the installations.
By nature, concrete is a very durable material and any natural Deterioration processes may take a long time to become critical to the structure. The experience of more than 50 years of service limits the testing tasks to a few ones which are not yet solved.
Research in NDT of concrete structures is performed by many research institutions all over the world with different technical and systematic approaches. Results are mainly obtained on laboratory specimens, sometimes additional field studies are reported. This research takes place independently without coordination and as a result, the outcomes mostly lack full comparability.
Software for data analysis has become indispensable and very powerful. This part of testing needs more attention when it comes to evaluate test results. Validation of NDE solutions is becoming a critical part in concrete structure testing.
Validation is by definition the proof that a customer´s requirements in the test are being met by the testing solution. This includes equipment, personnel qualification and data analysis. In the following tables, the research recommendation Validation is used in the sense, that proof of the performance of existing solutions needs to be adressed. In general, a validation methodology for NDE solutions for concrete testing in itself needs to be researched and established.
Comparability of research also needs an accepted and easily accessible reference. From experience, it is almost impossible to manufacture exact copies of test specimens at different locations. Round Robin tests are therefore needed to evaluate the performance of a test.
Data evaluation is generally done using dedicated software, sometimes Hardware dependant and not interchangeable between systems. Software is ever more increasingly becoming more powerful and sophisticated. An in-depth evaluation needs to address the comparability and validation of Software used for data analysis and evaluation. The vision of a unified software pool for NDE investigations would undoubtedly support research tremendously.
Quantitative NDE is mostly recommended to assess the condition of a structure. However, qualitative data can be very useful, especially for processes which change the material properties or deteriorate the structure (e.g. corrosion of reinforcement). The need for reliable baseline data is a key factor for such monitoring tasks.
Thermodynamics of LNG
(2020)
Densities of eight gravimetrically prepared ternary and quaternary gas mixtures consisting of methane, ethane, propane, and partially nitrogen were investigated along the four isotherms of –250, –230, –210, and –190 °F at pressures of 350, 500, 650, and 1000 psig using a cryogenic single-sinker densimeter. The experimental densities were compared to densities calculated by various models, namely the EOS-LNG fundamental Helmholtz equation of state, the COSTALD correlation, the Lee-Kessler-Plöcker equation of state, and the Peng-Robinson equation of state. The best performance was shown by the EOS-LNG equation of state which is capable of predicting the liquid densities within the specified uncertainty of the model of 0.05 %. The other models, however, showed significant differences that disqualify for calculation within the p,T-region investigated of the gas mixtures.
This is the first part (Deliverable 6-1) of workpackage 6 (WP6) in the framework of a research project funded by the European Community on the "Quantification and control of the hazards associated with the transport and bulk storage of fireworks" which was given the acronym CHAF. The work in this package aims to characterize selected packaged fireworks in standard UN classification tests by measuring the physical conditions (temperature, pressure, radiation, etc.), acting during testing and to use the results to provide benchmark data for the rest of the CHAF project. The objective of Deliverable 6-1 was to identify the types of fireworks that should be used for the benchmarking tests. This was achieved by developing the information generated in the literature review for the project (WP4). A critical element of the work was to attempt to identify fireworks close to the boundaries between different UN Hazard Divisions so that the accuracy of the UN classification assignments, as applied to fireworks, could be tested. This document outlines the types of fireworks selected for benchmark testing and the rationale behind the selection. Having identified the fireworks required a way forward to identify suitable suppliers is given.
This report is a literature review of the current state of knowledge of fireworks
and fireworks hazards. It presents work to meet Deliverables D4-1 (types and compositions
of fireworks Articles), D4-2 (Functioning mechanism of and between fireworks
articles), D4-3 (Storage and transport regulations in EU countries) and D4-4 (The effect
of fireworks on health and the environment) of the CHAF work program.
Firework compositions are discussed in the first section. This leads to an understanding
of the variability in performance of various types of fireworks. Compositions
used in report effects are highlighted as being the most energetic while other compositions
are seen as providing a much lesser hazard in mass storage of fireworks. Individual
types of firework are examined. Large devices such as report shells are identified as
posing the largest hazard in bulk storage. Lesser, but still significant, hazards are predicted
for similar compositions in Roman candles and rockets. Gradations in hazard are
identified corresponding to UN hazard divisions 1.1, 1.3 and 1.4.
The second section reports the literature relating to the functioning mechanism of
and between fireworks articles. In this the major propagation mechanisms for fireworks
compositions are examined. The main stimuli identified are: fragment impact, heat and
shock wave, each of which can lead to the functioning of pyrotechnic composition in
the article or in an adjacent article leading to large-scale initiation. Consideration of the
pyrotechnic compositions leads to a different ranking for the three mechanisms with different
fireworks types. Thus with a report composition containing a metal/perchlorate
mixture shock initiation is seen to be the main propagation mechanism. Such a mechanism
is likely to afford a mass explosion. At a lesser hazard, blackpowder-based compositions
are reported to be more likely to propagate via a flame mechanism. This is less
likely to produce a mass explosion.
National legislation concerning the storage of fireworks for many European countries
is considered in the third section. Many of the national regulations are based on a
cube root of explosives content to determine "safety distances", often written as Q1/3.
Different multiplying factors are then applied depending on the type of adjacent site
(production buildings, residential housing, roads etc.). Commonly 22Q1/3 is used for residential
dwellings. Special provisions are enacted in many countries either to allow
lesser distances or in some cases to increase the safety distances depending on the
perceived hazard or extenuating circumstances.
The final section deals with the environmental hazards posed by the use of
fireworks. Toxic effects of the materials used in the manufacture and the likely reaction
products from functioning fireworks are highlighted. These range from heavy metal
poisoning from metals present for their colour effect to respiratory problems due to
pyrotechnic fume (both particulate and gaseous). Finally, noise pollution is considered.
While there is a short term problem from pyrotechnic fume at times of high usage
(national celebrations) there is no literature evidence, as yet, of long term detriment to
the environment.