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The OECD validation study of the zebrafish embryo acute toxicity test (ZFET) for acute aquatic toxicity testing evaluated the ZFET reproducibility by testing 20 chemicals at 5 different concentrations in 3 independent runs in at least 3 laboratories. Stock solutions and test concentrations were analytically confirmed for 11 chemicals. Newly fertilised zebrafish eggs (20/concentration and control) were exposed for 96 h to chemicals. Four apical endpoints were recorded daily as indicators of acute lethality: coagulation of the embryo, lack of somite formation, non-detachment of the tail bud from the yolk sac and lack of heartbeat. Results (LC50 values for 48/96 h exposure) show that the ZFET is a robust method with a good intra- and inter-laboratory reproducibility (CV < 30%) for most chemicals and laboratories. The reproducibility was lower (CV > 30%) for some very toxic or volatile chemicals, and chemicals tested close to their limit of solubility. The ZFET is now available as OECD Test Guideline 236.Considering the high predictive capacity of the ZFET demonstrated by Belanger et al. (2013) in their retrospective analysis of acute fish toxicity and fish embryo acute toxicity data, the ZFET is ready to be considered for acute fish toxicity for regulatory purposes.

The NATO Research and Technology Organization (RTO), Advanced Vehicle Technology (AVI), Working Group (WG) 016 (formerly AGARD/PEP Working Group (27) undertook to evaluate methods in use within the NATO propulsion community to measure burning rate in solid propellant rocket systems, with the purpose of identifying similarities and differences between the participating nations. This WG was formed in 1996, consisting of active representatives from 6 of the 15 member nations of NATO, with inputs accepted from 4 other member nations and a couple non-member nations. The NATO RTO/AVT WG 016 sought to contribute to improvements in the burning rate tools to address issues that have plagued the solid propulsion industry for over 40 years. This paper reviews the final results of this study by summarizing the objectives, approach, findings, and recommendations of this working group based on activity from October 1997 to March 2001. Recommendations are reviewed on direct and non-intrusive burning rate measurement methods, data analysis, and performance scaling to support improved prediction of internal ballistics of a full-scale solid propellant motor. AVT WG 016 activities have identified that manufacturer burning rate data may not easily be compared without accounting for industry-wide differences in subscale devices, test methods and scaling analysis methods. The WG recommends the NATO propulsion community review these findings as a means of advancing their own burning rate measurement and analysis methods.

The analysis of cellulose properties as determined by X-ray diffraction is described in this report. Results for several cellulose samples - both pulp and linter - are presented. A preliminary correlation between the measured properties of cellulose with properties of cellulose nitrate prepared therefrom is suggested., SBIE-ADE400468.

Isotactic polyvinyl nitrate (PVN) was prepared to investigate the effect of stereoregularity on the physical properties of PVN. The isotatic PVN had a higher softening point and was more difficult to stabilize than regular PVN.