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Tribological profile of hydraulic oils by using SRV. The determination of a set of critical, tribological by using different SRV-based test methods. The SRV-based concept of tribological profile generates the wear volumes on two triboelements (specimen), the extreme pressure properties and friction under different contact pressures.
Thus, the benchmark and validation of hydraulic oils bear on a wider range of tribological properties.
The RR2016 extends with six hydraulic oils to other base oil types including biodegradable fluids, which were all tested according to ASTM D7043 in order to consolidate the correlation between SRV and V104C.
Actions from the meeting in April 2016: 1. Four SAC test methods are in place and were revised: SH/T 0721 (Grease, coefficient of friction and wear), SH/T 0784 (Grease, pass load/O.K. load), SH/T 0847 (Oil, coefficient of friction and wear) and SH/T 0882 released by 11-2014 (Oil, pass load/O.K. load). 2. New test method to evaluate anti-fretting properties of greases based was approved by SAC TC280 and will be released. 3. SAC TC280 accepted the project “Simulation of synchronizer by using SRV”. Draft text to be submitted by 03-2017. Discussions on a parallel ASTM test method. 4. A procedure for “Wear Volume” is under development for SAC TC280.
South Africa and recently Nigeria are the only net exporter of cement in Africa, yet cements are imported into the country mainly on the basis of price competitiveness. This poses potential for scatter in the properties of the cements in the South African market as pricing seems to be the only determining factor that affects Portland cements imported. A survey of cements of grade 42.5N in the South African cement market was carried out to identify major players in the industry. The identified cements, which included four locally produced and one imported cement were then analysed for both chemical composition and physical properties in line with the Eurocode EN 196. Tests carried out include loss on ignition, chloride content, sulphate content, specific surface (Blaine), standard consistence, initial setting time, final setting time, soundness and flexural and compressive strength at 2, 7 and 28 days. The testing program was initiated as part of on-going Africa-wide cement testing competency program in partnership with BAM and PTB in Germany. The performance of the identified cements from the different local manufacturers and the imported cement were analysed and are presented in this paper. These results reveal some similarities and differences in the properties. Particularly of interest is the marked difference in the 28 days compressive strength of the cements. This paper shows that there is need for further tests across the cement industry as some of the cements failed to meet certain requirement as set by EN 196. The paper also recommends the use of proficiency testing schemes in the cement industry of the country to ensure the cement laboratories are providing results of high quality and at the same time act as a check to make sure these laboratories are not failing to meet standard requirements.
Dye-stained micrometer-sized polymer beads are important tools in the life sciences with applications in biomedical, biochemical, and clinical research. Here, bead-based assays are increasingly used, for example, in DNA sequencing and the detection of autoimmune diseases or pathogenic microorganisms. Moreover, stained beads are employed as calibration tools for fluorescence microscopy and flow cytometry methods with increasing complexity. To address the requirements concerning the relevant fluorescence features, the spectroscopic properties of representative polymer beads with diameters ranging from about 1 to 10 μm stained with varying concentrations of rhodamine 6G were systematically assessed. The observed dependence of the spectral properties, fluorescence decay kinetics, and fluorescence quantum yields on bead size and dye loading concentration is attributed to different fluorescence characteristics of fluorophores located in the particle core and near-surface dye molecules. Supported by the fluorescence anisotropy measurements, the origin of the observed alteration of fluorescence features is ascribed to a combination of excitation energy transfer and polarity-related effects that are especially pronounced at the interface of the bead and the surrounding medium. The results of our studies underline the need to carefully control and optimize all Parameters that can affect the fluorescence properties of the dye-stained beads.
The presentation will discuss the difference between EU and US standards for the determination of explosion (flammability) limits and limiting oxygen concentration. Small differences observed in measured values can be traced back to the different test apparatuses and criteria. The discrepancies can be much greater in the case of limiting oxygen concentration because of the high amount of inert gases and the corresponding low laminar burning velocities. The paper describes some examples and the influence of the chosen criteria on the results. The European and US standards use the criteria of flame propagation in open test vessels and of pressure rise in closed ones. The examples discussed show that flame propagation is still possible at very small pressure rise values, as observed much below the pressure rise criterion of usual standards. However, flame propagation in a process plant can cause an accident or explosion and must be avoided. Therefore, the flame propagation criterion is recommended to be used in chemical safety engineering. The European safety database CHEMSAFE contains expertevaluated safety data for cases where the determination method and criteria are known. Flammability characteristics based on the pressure rise criterion may suffice in certain cases, e.g. for explosion protection in closed vessels without any connecting pipes.
This chapter provides an overview of what standards are, why they are important, and how they are developed. There is a focus on the work of standards committees relevant to nanotechnology measurement and characterization with tables detailing the standards that are currently available for a large number of different techniques, materials, and applications at the nanoscale.
Introduction
(2020)
The purpose of this book is to provide a comprehensive collection of analytical methods that are commonly used to measure nanoparticles, providing information on one, or more, property of importance. The chapters provide up-to-date information and guidance on the use of these techniques, detailing the manner in which they may be reliably employed. Within this chapter, we detail the rationale and context of the whole book, which is driven by the observation of a low level of reproducibility in nanoparticle research. The aim of the book is to encourage awareness of both the strengths and weaknesses of the various methods used to measure nanoparticles and raise awareness of the range of methods that are available. The editors of the book have, for many years, been engaged in European projects and standardization activities concerned with nanoparticle analysis and have identified authors who are experts in the various methods included within the book. This has produced a book that can be used as a definitive guide to current best practice in nanoparticle measurement.
Over the last couple of years a lot of effort was put into the development of internationally recognized standards for fireworks. The work is globally organized within the ISO/TC 264 “Fireworks”. This technical committee consists of five working groups (WGs), set up for the development of criteria for safety requirements, test methods and labelling of fireworks articles:
WG1: Terminology
WG2: Safety requirements and labelling
WG3: Categories and types
WG4: Test methods
WG5: Fireworks display
The Bundesanstalt für Materialforschung und -prüfung (BAM) was from the beginning part of the entire standardization activities and participated actively with experts in all WGs, project leadership and provided the chairman for the ISO/TC 264-WG2 “Safety requirements and labelling”. This paper aims at giving an overview about the meetings, the philosophy behind the chosen standardization approaches and selected information on safety requirements, test methods and labelling aspects.
Over the last couple of years a lot of effort was put into the development of internationally recognized standards for fireworks. The work is globally organized within the ISO/TC 264 “Fireworks”. This technical committee consists of five working groups (WGs), set up for the development of criteria for safety requirements, test methods and labelling of fireworks articles:
WG1: Terminology
WG2: Safety requirements and labelling
WG3: Categories and types
WG4: Test methods
WG5: Fireworks display
The Bundesanstalt für Materialforschung und -prüfung (BAM) was from the beginning part of the entire standardization activities and participated actively with experts in all WGs, project leadership and provided the chairman for the ISO/TC 264-WG2 “Safety requirements and labelling”. This paper aims at giving an overview about the meetings, the philosophy behind the chosen standardization approaches and selected information on safety requirements, test methods and labelling aspects.
The mechanical characterization of adobe bricks is an important first step in the study of the behaviour of adobe masonry. For this reason, in the last decades, different authors have conducted research on the mechanical behaviour of adobes from various regions of the world. Despite the importance of mechanical characterization, there are still only a few standards and normative documents with clear indications for the mechanical testing of earthen materials and, in general, These indications are not thorough and vary among different countries. Consequently, authors tend to adopt different types of test specimens and procedures in their experimental work, thus obtaining results that are not directly comparable. The fact that the materials and procedures traditionally used are also not standardized,varying greatly from region to region, also contributes to the difficulty of comparing results from different studies. This chapter presents a review of the indications provided by codes, standards and other technical recommendations for the mechanical testing of adobe bricks, as well as a detailed review of procedures adopted, and results obtained by different authors regarding the mechanical characterization of traditional adobe bricks. This chapter focuses, in particular, on the behaviour of adobe bricks when subjected to simple compression. It provides an overview of the existing knowledge and identifies needs for future research and development.