Chemistry Journal of Moldova

https://doi.org/10.19261/cjm.2023.1100  

 

Abstract (PDF)
Graphical Abstract: The extracts from the leaves of Deschampsia antarctica, Camelina sativa, and Camellia japonica plants, as well as from Camelina sativa and Silybum marianum seedcakes were investigated as potential additives for improvement of biodiesel stability against oxidation. In spite of significant distinctions in the content of various phenolic compounds, all the extracts were found to effectively inhibit DPPH radicals and decelerate transformation of fatty acid esters of biodiesel into organic acids by ~9-26%. Various extracts were shown to have different activity towards the biodiesel from rape and camelina seed oils; this result is consistent with the assumption that there is no universal stabilizer for different types of biodiesel.

https://doi.org/10.19261/cjm.2023.1083  

 

Abstract (PDF)
Graphical Abstract: DFT computations identify the effects that enable the synthesis of geometrically-strained epoxide from deprotonated halohydrins. These computations also explain the preference for the formation of larger cyclic ethers with five-atom rings over six-atom-rings. Increased temperature favors elimination over S_N2 only when the reacting moieties are part of separate molecules.

https://doi.org/10.19261/cjm.2023.1081  

 

Abstract (PDF)
Graphical Abstract: The isothermal section of the La₂O₃–Lu₂O₃–Er₂O₃ phase diagram at 1250°C has the characteristic three one-phase fields (A-La₂O₃, R, C-Lu₂O₃(Er₂O₃)) corresponding to solid solutions based on starting components and two two-phase fields (C + R, A + R) between them. 
 

https://doi.org/10.19261/cjm.2023.1098  

 

Abstract (PDF)
Graphical Abstract: This paper discusses the notion of symmetry of polyatomic systems defined as invariance under transformations, and showes that this important property of atomic matter is extremely vulnerable, and may undergo internal breakdown, subject to the presence of electronic degeneracy or pseudodegeneracy. It is shown that electronic degeneracy and its extended form, called pseudodegeneracy, are actually the only source of spontaneous symmetry breaking (SSB) in nature, including all forms of matter, beginning with elementary particles, via nuclei, atoms, molecules, and solids. Theoretically, the vulnerability of the notion of symmetry is due to the fact that, following quantum mechanics, the separation of the motion of electrons and nuclei (and, similarly, the separation of motions of elementary particles) is approximate, and hence the classical notion of polyatomic space configuration is approximate too, with SSB as one of its main violation.


 

Abstract (PDF)
Supplementary Material (PDF) 
Graphical Abstract: The crystal structure of 1,5-bis(2-hydroxy-3-methoxybenzylidene) carbonohydrazide was determined by X-ray single crystal diffraction study. In solid-state the molecule adopts the anti keto conformation, while NMR studies proved evidence on the presence of its syn tautomer in DMSO solution.