On the use of ASTM closed vessel tests in accelerated ageing research     

Tomasz Sawoszczuk  Andrzej Bara&#x;ski  Janusz Marek &#x;agan  Tomasz &#x;ojewski  Katarzyna Zi&#x;ba 《Journal of Cultural Heritage》2008,9(4):401-411

The ASTM D6819-02e3 standard for testing the accelerated ageing of paper, published in 2002, recommends using closed glass vials in order to keep the degradation products in contact with the paper and thus permitting a better simulation of the natural ageing conditions inside closed books. In the present study, the actual conditions and their stability inside closed vessels have been evaluated. The necessity of assuring a very high sealing performance (tightness) of the systems in order to avoid leakage of water vapour is the main drawback of this ageing method. Systematic studies presented in this publication tried to monitor this tightness and have provided data that helped to answer the question of what circumstances could lead to achieving its improvement. Both gravimetric monitoring of water content in vials and “in situ” IR measurements of the aged paper humidity have been applied for this purpose. As a result, better sealing materials (gaskets and caps) than those recommended by the ASTM standard, have been found. Additionally, application of a dynamometric spanner for closing the vials is recommended, as this is a guarantee of reasonably high and recurring tightness of the systems used in tests. Nevertheless, the systematic, linear with time, loss of moisture for all used vials was observed. A 9% loss of the initial moisture content in samples of the aged paper was observed for the tested conditions (14 days at 90 °C). Therefore, it seems that including some kind of gravimetric control for ageing tests performed in closed vessels is of essential importance.Kinetic studies of accelerated ageing in both closed and open systems, as monitored by DP and breaking length measurements, unexpectedly show that no statistically meaningful difference of degradation rates can be observed. On the other hand, the pH and whiteness index values reveal a meaningful difference between the rates of ageing in these systems, thus confirming the basic assumption of the ASTM test concerning the interaction of paper degradation products with the paper itself.  相似文献   

Reconsidering laboratory-based anatomy within the backdrop of digital transformation: Bringing an old practice into a new world     

Nirusha Lachman Ph.D.  Wojciech Pawlina M.D. 《Anatomical sciences education》2022,15(3):439-446

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All that glitters is not gold—Mixed early labour market outcomes of STEM graduates in Poland     

Tomasz Z. Zając  Tomasz Żółtak  Marek Bożykowski  Mikołaj Jasiński 《European Journal of Education》2023,58(3):477-497

The expansion of higher education resulted in a growing interest in post-graduation labour market outcomes. Two conflicting narratives are present in the debate. The first focuses on the shortage of skills and the need for further expansion of the sector and seems to pertain mostly to science, technology, engineering, and mathematics (STEM). The second revolves around over-education and mismatch leading to graduate unemployment or underemployment. Such concerns pertain especially to humanities and social sciences. However, in this article, we argue that the STEM versus non-STEM opposition on which this debate is premised is not adequate for analysing post-graduation labour market outcomes. We leverage a unique administrative dataset comprising monthly records on the labour market status of the entire population of recent Polish university graduates (N = 161,323) to demonstrate the heterogeneity of the STEM category in terms of labour market outcomes and the limited predictive value of the field of study for those outcomes. We argue that the category is too broad and internally diverse to be used as an overarching category, especially in research meant to inform policymaking.  相似文献   

‘Cracks’ in the scholarly communications system: Insights from a longitudinal international study of early career researchers     

David Nicholas  Cherifa Boukacem-Zeghmouri  Blanca Rodríguez-Bravo  Eti Herman  Abdullah Abrizah  David Clark  Galina Serbina  David Sims  Marzena Świgoń  Jie Xu  Anthony Watkinson  Hamid R. Jamali  Carol Tenopir  Suzie Allard 《Learned Publishing》2023,36(2):319-322

• 170 early career researchers interviewed three times over 2 years, have uniquely contributed towards a stress test of scholarly communications and cracks have been identified.
• The perfect storm created by the convergence of millennial values and the pandemic appears to have fast-forwarded the cracking process, perhaps, for the good.
• The cracks in question are: (1) peer review; (2) reputational assessment; (3) unethical/questionable practices; (4) collaboration; (5) networking.

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