Laser flash photolysis of polyfluorinated aryl azides in acetonitrile at ambient temperature produces singlet nitrenes which have lifetimes of tens to hundreds of nanoseconds. The lifetimes are controlled by ring expansion and intersystem crossing to the lower energy triplet state. In the presence of sulfuric acid the singlet nitrene can be protonated to form a new species whose transient absorption is attributed to a nitrenium ion. This assignment is based in part on analogy to other nitrenium ion spectra and studies reported recently by Falvey (J. Am. Chem. Soc. 1993, 115, 7254) and McClelland and Novak (J. Am. Chem. Soc. 1994, 116, 4513) and to the protonation of p-biphenylnitrene reported by Davidse et al. (J. Am. Chem. Soc. 1994, 116, 4513). The polyfluorinated nitrenium ions likely have singlet ground states, consistent with recent calculations of the parent structure.

In this study, the results obtained by 19 laboratories participating in 2 editions of the interlaboratory comparison (ILC) determining 2 properties of ceramic tiles adhesives (CTAs), i.e., initial tensile adhesion strength and tensile adhesion strength after water immersion following EN 12004, were analyzed. The results show that participating laboratories maintain a constant quality of their work. The use of z-score analysis, under ISO 13528, allows for classifying 89.5% to 100% of laboratories as satisfactory, depending on the measurement’s kind and edition. The remaining laboratories are classified as questionable. The investigation of the predominant mode of failure of the CTA’s samples tested in the two editions shows significant differences. From the perspective of laboratories, the goal of the ILC has been achieved. From the standpoint of a manufacturer who evaluates a product’s properties when placing it on the market, the results indicate the necessity of a particular treatment of the product evaluation process because the variability of the obtained results is significant. It increases the possibility of the product failing to meet the assessment criteria verified by the construction market supervision authorities. The manufacturer must consider all possible variations in the risk analysis, including the ILC results, to improve the assessment process of CTAs.

This article presents the results of the interlaboratory comparison (ILC) study of the following four characteristics of ceramic tile adhesives (CTAs): initial tensile adhesion strength, tensile adhesion strength after heat ageing, tensile adhesion strength after immersion in water, and tensile adhesion strength after freeze–thaw cycles. The results showed that the objective of the ILC was achieved—the z-score analysis carried out following ISO 13528 allowed for classifying all results obtained by 23 laboratories out of 27 as satisfactory. The results of the remaining four laboratories were rated worse. Despite the achieved goal, the ILC notes high heterogeneity of the results in terms of failure patterns, as well as significant differences between the lowest and the highest values of tensile adhesion strength for various measurement conditions. The results of the ILC were discussed in terms of the possibility of including them in the risk analysis conducted by the manufacturer. The results of the ILC are also valuable information for market surveillance authorities, who, in the authors’ opinion, should be more cautious about results on samples taken from the market. The ILC results for CTAs are also a valuable recommendation for a possible revision of EN 12004.

The external thermal insulation composite system (ETICS) improves the energy efficiency of buildings, and nowadays, this method is the most popular to insulate buildings in many European Union (EU) countries. The article presents the impact of producing ETICS with expanded polystyrene (EPS) or mineral wool (MW) on the natural environment using the life cycle assessment (LCA) method. The data used in the calculations, related to 2017 real production, were obtained from the externally verified inventory from five manufacturing plants located in different regions of Poland. The LCA of the examined products covered modules from A1 to A3 (cradle-to-gate), according to EN 15804 standard. The study determines and analyses the values of basic indicators related to environmental impacts and environmental aspects of resource use. It comprises indicators calculated for 1 m2 ETICS for five thicknesses of the mentioned thermal insulation materials. Results show that for all environmental indicators, MW systems are characterized by a more negative environmental impact than the equivalent systems with EPS. The study aims to highlight knowledge about ETICS sustainability. The data presented in work are essential for assessment in terms of the sustainable development of ETICS. Such an evaluation is not just a need for the future but a necessity for the present.

This work attempts to draw attention to the importance of a multidimensional approach when creating standard requirements in the assessment of construction products with the example of ceramic tile adhesives (CTAs). CTAs are an essential group of building materials today, the continuous development of which has been noted since the 1960s. However, until 2001, i.e., the year when EN 12004 was published, there were no precise requirements for CTAs at the European level, which often made it difficult or, in extreme cases, even impossible to assess the product objectively. Under the provisions of EN 12004, for twenty years, the basis for the assessment and verification of constancy of performance (AVCP) of CTAs has been adhesion determined by tensile strength. The paper discusses the test methods, paying attention to their imperfections, including the impact of the materials used in measurements, i.e., concrete slab, ceramic tile, and water quality. The results of the multi-annual interlaboratory tests indicate that an essential factor that must be considered in the process of AVCP is test measurement uncertainty. Additionally, it should be remembered that uncertainty also occurs at other assessment levels. It also seems that the simple acceptance rule that does not consider the variability resulting from the measurement uncertainty is inadequate when assessing CTAs.