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The paper describes the problem of identifying the properties of a glue-wood beam in operation (with prolonged loading and variable temperature). Tests were carried out on model structures with prolonged transverse bending and constant temperature variations. During the tests, the values of stresses and deflections were recorded in a wide range of loads and temperatures. Stress diagrams are plotted for all investigated models. The results obtained showed that the presence of an adhesive layer significantly affects the bearing capacity and deformability of wood, which must be taken into account when designing wooden structures.

In areas rich in large-sized wood in low-rise buildings, are composite wooden structures. Compliance in calculations of such structures is taken into account by factors. Compliance factors are determined experimentally with a large spread of values, which leads to a significant overstatement of the material intensity of the structures. Issues of error of calculation of bearing capacity of composite wooden elements at variation of their layering are considered in the work.

A three-component reaction involving in situ generation of propargylureas and subsequent Zn(OTf)2-mediated cyclocondensation with a primary amine yielded trisubstituted 2-aminoimidazoles. These findings are in contrast to the previously reported base-promoted unimolecular cyclization of propargylureas (leading to 2-imidazolones) and extend the range of Lewis acid-catalyzed azole syntheses based on N-carbonyl propargylamines.

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