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Biothermodynamics is a discipline which has developed intensely during the last 50 years. Thermodynamic properties have been reported for humans, animals, plants and microorganisms. However, this paper reports for the first time the empirical formula and thermodynamic properties for insects. Thermodynamic properties can be applied in research on thermodynamic interactions between organisms and their environment, as well as between organisms themselves. This paper reports for the first time the empirical formula and reactions of catabolism, biosynthesis and entire metabolism are formulated for Bombyx mori (domestic silk moth), as well as the thermodynamic properties of B. mori. It is shown that growth of B. mori is tightly related to catabolism of carbohydrates and lipids, which represents the driving force for the entire metabolism.

Today, the World Health Organization has declared a global health emergency, caused by the Monkeypox outbreak. In the monthly analysis for June, 3500 cases have been reported in 50 countries around the world. In the analysis for July, more than 30000 cases have been reported in 75 countries. Thus, in the circumstances of the continuing COVID-19 pandemic, the appearance and dynamics of spreading of Monkeypox is alarming. In this paper, for the first time, elemental composition of Poxvirus, Monkeypox virus, and Vaccinia virus have been reported. Additionally, thermodynamic properties have been reported for nucleic acids, nucleocapsids, and entire virus particles. The similarity in chemical composition and thermodynamic properties of the analyzed viruses has been used to explain the crossed immunity to Poxviruses. Finally, binding thermodynamic properties have been reported for the Vaccinia virus.

The model of T4 phage, Lambda phage, and E. coli is often used in research on virus-host interactions. This paper reports for the first time the thermodynamic driving force of biosynthesis, catabolism and metabolism for the three organisms, on the M9 medium. Moreover, the influence of activities of nutrients and metabolic products is analyzed. All three organisms were found to have very similar Gibbs energies of metabolism. Moreover, since they share the same catabolism, their Gibbs energies of catabolism are identical. However, Gibbs energies of biosynthesis differ. The calculated thermodynamic properties have been used to explain the coexistence of both bacteria and phages in a dynamic equilibrium in natural ecosystems.

The guarded hot plate (GHP) method is a widely used technique to measure thermal conductivity of thermal insulation specimens in steady-state conditions. In this paper, an advance of GHP has been developed in the Laboratory for Thermal Technique and Fire Protection in Institute IMS. The innovative GHP has been applied for measuring thermal conductivity using additional heat flux meters. The design of this GHP is similar to the design of the plate for GHP apparatus, however, it has different design: smaller width of thermal barrier, which is filled with insulation glue. Heaters inside hot and guard plates are built from wire for thermocouples, which is a unique type of heater. Geometry of heater has been optimized inside plates to achieve uniform temperature distribution along the specimen surface. Temperature uniformity of GHP and energy balance were experimentally determined. The verification and validation results of improved GHP have been shown. The test method was validated comparing test results of thermal conductivity with results of the round-robin test. Four national companies participated in the round-robin comparison on thermal conductivity measurement by GHP method. The measurement was performed on the same specimen of thermal insulation material (expanded polystyrene) according to SRPS EN 12667 at temperatures ranging between 10-40 °C. The measured thermal conductivity of all participants in the round-robin test was input data for statistical processing according to SRPS ISO 5725-2 and ISO 13528. To evaluate the performance of the participants, the “z” score has been used. Measurements were conducted successively for all participants. Since 2020, the Accreditation Body of Serbia also approved this test method.

Comment on a paper: Trancossi, M., et al., A Critical Review on Heat and Mass Transfer Modelling of Viral Infection and Virion Evolution: The Case of SARS-CoV2, Thermal Science, 25 (2021), 4A, pp. 2831-2843.

This paper reports empirical formulas, enthalpies of formation, molar entropies, Gibbs energies of formation, and molar heat capacities at 25°C and 37°C for human soft tissues. The results show that Gibbs energy, except for certain tissues (adipose), is relatively low compared with the constituent elements, the average value being –17.57 kJ/C-mol. The average constant pressure heat capacity of hydrated human body soft tissues is 3.24 J/gK in agreement with other data in the literature.

Most people would face a problem if there is a need to calculate the mole fraction of a substance A in a gaseous solution (a thermodynamic system containing two or more ideal gases) knowing its molarity at a given temperature and pressure. For most it would take a lot of time and calculations to find the answer, especially because the quantities of other substances in the system aren’t given. An even greater problem arises when we try to understand how special relativity affects gaseous systems, especially solutions and systems in equilibrium. In this paper formulas are suggested that greatly shorten the process of conversion from molarity to mole fraction and give us a better insight into the relativistic effects on a gaseous system.