Synergy As One Of The Constructive Principles Of The System Formation

Author(s):  
Nurvadi Al'bekov
Keyword(s):  
2019 ◽  
Vol 1 (4) ◽  
pp. 348-359
Author(s):  
О. Taran ◽  
S. Kudryashova

Author(s):  
Irina Bubnova ◽  
◽  
Oksana Kazachenko ◽  
Elena Tokareva ◽  
◽  
...  

2020 ◽  
Vol 500 (2) ◽  
pp. 1697-1707
Author(s):  
Paul C Clark ◽  
Anthony P Whitworth

ABSTRACT We propose a new model for the evolution of a star cluster’s system mass function (SMF). The model involves both turbulent fragmentation and competitive accretion. Turbulent fragmentation creates low-mass seed proto-systems (i.e. single and multiple protostars). Some of these low-mass seed proto-systems then grow by competitive accretion to produce the high-mass power-law tail of the SMF. Turbulent fragmentation is relatively inefficient, in the sense that the creation of low-mass seed proto-systems only consumes a fraction, ${\sim }23{{\ \rm per\ cent}}$ (at most ${\sim }50{{\ \rm per\ cent}}$), of the mass available for star formation. The remaining mass is consumed by competitive accretion. Provided the accretion rate on to a proto-system is approximately proportional to its mass (dm/dt ∝ m), the SMF develops a power-law tail at high masses with the Salpeter slope (∼−2.3). If the rate of supply of mass accelerates, the rate of proto-system formation also accelerates, as appears to be observed in many clusters. However, even if the rate of supply of mass decreases, or ceases and then resumes, the SMF evolves homologously, retaining the same overall shape, and the high-mass power-law tail simply extends to ever higher masses until the supply of gas runs out completely. The Chabrier SMF can be reproduced very accurately if the seed proto-systems have an approximately lognormal mass distribution with median mass ${\sim } 0.11 \, {\rm M}_{\odot }$ and logarithmic standard deviation $\sigma _{\log _{10}({M/M}_\odot)}\sim 0.47$).


Photochem ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 167-189
Author(s):  
Alexandre Mau ◽  
Guillaume Noirbent ◽  
Céline Dietlin ◽  
Bernadette Graff ◽  
Didier Gigmes ◽  
...  

In this work, eleven heteroleptic copper complexes were designed and studied as photoinitiators of polymerization in three-component photoinitiating systems in combination with an iodonium salt and an amine. Notably, ten of them exhibited panchromatic behavior and could be used for long wavelengths. Ferrocene-free copper complexes were capable of efficiently initiating both the radical and cationic polymerizations and exhibited similar performances to that of the benchmark G1 system. Formation of acrylate/epoxy IPNs was also successfully performed even upon irradiation at 455 nm or at 530 nm. Interestingly, all copper complexes containing the 1,1′-bis(diphenylphosphino)ferrocene ligand were not photoluminescent, evidencing that ferrocene could efficiently quench the photoluminescence properties of copper complexes. Besides, these ferrocene-based complexes were capable of efficiently initiating free radical polymerization processes. The ferrocene moiety introduced in the different copper complexes affected neither their panchromatic behaviors nor their abilities to initiate free radical polymerizations.


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