Centrally essential rings Markov, Viktor T.; Tuganbaev, Askar A.
Discrete mathematics and applications,
06/2019, Volume:
29, Issue:
3
Journal Article
Peer reviewed
A centrally essential ring is a ring which is an essential extension of its center (we consider the ring as a module over its center). We give several examples of noncommutative centrally essential ...rings and describe some properties of centrally essential rings.
Centrally essential rings were defined earlier for associative unital rings; in this paper, we define them for rings which are not necessarily associative or unital. In this case, it is proved that ...centrally essential semiprime rings are commutative. It is proved that all idempotents of a centrally essential alternative ring are central. Several examples of non-commutative centrally essential rings are provided, some properties of centrally essential rings are described.
We investigate the possibility to use non-associative groupoids in the realization of an open key distribution procedure based on a generalization of the well known Diffie-Hellman algorithm.We prove ...the existence of non-associative groupoidswhich are simultaneously power commuting and not power-associative.
It has been suggested that highly social mammals, such as naked mole rats and humans, are long-lived due to neoteny (the prolongation of youth). In both species, aging cannot operate as a mechanism ...facilitating natural selection because the pressure of this selection is strongly reduced due to
) a specific social structure where only the "queen" and her "husband(s)" are involved in reproduction (naked mole rats) or
) substituting fast technological progress for slow biological evolution (humans). Lists of numerous traits of youth that do not disappear with age in naked mole rats and humans are presented and discussed. A high resistance of naked mole rats to cancer, diabetes, cardiovascular and brain diseases, and many infections explains why their mortality rate is very low and almost age-independent and why their lifespan is more than 30 years, versus 3 years in mice. In young humans, curves of mortality versus age start at extremely low values. However, in the elderly, human mortality strongly increases. High mortality rates in other primates are observed at much younger ages than in humans. The inhibition of the aging process in humans by specific drugs seems to be a promising approach to prolong our healthspan. This might be a way to retard aging, which is already partially accomplished via the natural physiological phenomenon neoteny.
A reaction of acyl chlorides derived from 1,10-phenanthroline-2,9-dicarboxylic acids with piperazine allows the preparation of the corresponding 24-membered macrocycles in good yield. The structural ...and spectral properties of these new macrocyclic ligands were thoroughly investigated, revealing promising coordination properties towards f-elements (Am, Eu). It was shown that the prepared ligands can be used for selective extraction of Am(III) from alkaline-carbonate media in presence of Eu(III) with an SF
up to 40. Their extraction efficiency is higher than calixarene-type extraction of the Am(III) and Eu(III) pair. Composition of macrocycle-metal complex with Eu(III) was investigated by luminescence and UV-vis spectroscopy. The possibility of such ligands to form complexes of L:Eu = 1:2 stoichiometry is revealed.
The paper presents a comparison that makes it possible to estimate the coefficients of electrical mobility of silver ions introduced from an external source from the electrical conductivity of alkali ...ions when they are equivalently replaced during the electrolysis process, which can be useful in calculating gradient structures in gradient optics and photonics.
Ionic Seebeck effect has been investigated in Li (Na,K)2O‐Nb2O5‐P2O5 glasses. Ionic Seebeck coefficients and heats of ion transfer have been measured. Soret coefficients have been calculated for ...glasses being studied. Temperature dependence and content of Nb2O5 dependence of Soret coefficients have been analyzed. Hypotheses of coefficients of self-diffusion and thermodiffusion ratio when temperature and content of Nb2O5 change have been proposed.
The electronic structure of lithium pyrophosphates (Li4P2O7) and sodium (Na4P2O7) was calculated by the density functional theory method. The calculations were performed for ordered (crystalline) and ...disordered (corresponding to glassy) structural states of lithium and sodium pyrophosphates. The disordering of the structure is simulated by ab initio molecular dynamics from crystal state with the same atomic basis as used for ideal crystal electronic calculations.
High yogurt consumption worldwide has opened the opportunity for designing a new concept of this fermented dairy product as an extremely valuable functional food item, fortified with bioactive ...components such as carotenoids. In this way, daily diets can become more effective in reducing diseases associated with nutritional deficiencies as well as alleviate the problem of accumulation of food by-products that are rich in bioactive components. In this study, after the extraction of carotenoids from carrot waste (CW) and complete characterization, the encapsulation process was carried out by electrostatic extrusion. Two concentrations of completely characterized CW beads (2.5 and 5 g/100g) were added to yogurt during the final step of yogurt preparation. Comparative studies of control and fortified yogurts were executed during a storage period of 28 d at 4 °C. Yogurt fortification with both concentrations provides a part of β-carotene recommended daily intake. Overall, microbiological and physico-chemical properties of the fortified yogurts were well-maintained during the storage period. The encapsulated carotenoids considerably improved the antioxidant activity of the yogurt; therefore, it can be used for the development of fortified yogurt with high nutritional properties.
•β-carotene extracted with sunflower oil from juice carrot waste were encapsulated.•Electrostatic extrusion technique and alginate as wall material were applied.•Obtained carrot waste-alginate beads gave promising physico-chemical and bioactive properties.•Yogurt fortification with 2.5% and 5% carrot waste beads provided sufficient concentration of β-carotene.•Microbiological and physico-chemical properties of the fortified yogurts were well-maintained during the storage period.
This paper presents data on the mixed alkali effect in two fundamentally different systems: chalcogenide and oxide (phosphate). In the first system (Ag – Cu)0.44AsSe1.5, the predominantly ionic ...conductivity of silver-containing glasses is replaced by purely electronic in copper-containing, in the second - 0.5(Li2O-Na2O) – 0.4P2O5 – 0.1Nb2O5 carriers of electric current are alkaline ions and the extreme dependences of the electrical parameters associated with their joint migration.
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