scholarly journals Efficacy Analysis of Panchromatic New Copper Complex for Visible Light (455, 530 nm) Radical/Cationic Photopolymerization: The Synergic Effects and Catalytic Cycle

Author(s):  
Jui-Teng Lin ◽  
Jacques Lalevee ◽  
Da-Chun Cheng

. This article presents, for the first time, the kinetics and the general conversion features of a 3-component system (A/B/N), based on proposed mechanism of Mau et al, for both free radical polymerization (FRP) of acrylates and the free radical promoted cationic polymerization (CP) of epoxides using various new copper complex (G2) as the initiator. Higher FRP and CP conversion can be achieved by co-additive of [B] and N, via the dual function of (i) regeneration [A], and (ii) generation of extra radicals. The FRP and CP conversion efficacy (CE) are proportional to the nonlinear power of bI[A][B], where b and I are the effective absorption coefficient and the light intensity, respectively. In the interpenetrated polymer network (IPN) capable of initiating both FRP and CP in a blend of TMPTA and EPOX, (as the monomer for FRP and CP, respectively), the synergic effects due to CP include:: (i) CP can increase viscosity limiting the diffusional oxygen replenishment, such that oxygen inhibition effects are reduced; (ii) the cationic monomer also acts as a diluting agent for the IPN network , and (iii) the exothermic property of the CP. Many new findings are explored via our analytical formuals include: (i) the CE of FRP is about twice of the CE of CP, due to the extra radicals involved in FRP; (ii) the catalytic cycle enhancing the efficacy is mainly due to the regenaration of the initiator, and (iii) the nonlinear dependence of light intensity of the CE (in both FRP and CP). For the first time, the catalytic cycle, synergic effects, and the oxygen inhibition are theoretically confirmed to support the experimental hypothesis. The measured results of Mau et al are well analyzed and matching the predicted features of our modeling. .

Author(s):  
Jui-Teng Lin ◽  
Jacques Lalevee

This article presents, for the first time, the kinetics and the general conversion features of a 3-component system, BT(BC)/iodonium/Amine, based on proposed mechanism of Liu et al, for both free radical polymerization (FRP) of acrylates and the free radical promoted cationic polymerization (CP) of epoxides using the new multi-functional initiator of benzophenone–triphenylamine (BT). The additives, iodonium and EDB, have the dual function of (i) regeneration BT and (ii) produce of extra radicals for improved FRP and CP. Analytic formulas are developed to explore the new features including: (i) the conversion efficacy (CE) of FRP is an increasing function of the light intensity, the effective absorption coefficient, and the concentration sum of each of the components, BT, Iod, amine, for transient state. However, CE at steady-state is independent to the light intensity; (ii) the trifunctional hybrid structures of BT3 leads to larger light absorption than other types of BT; it also provides more active sites for the H-abstraction in the presence of EDB, leading to high CE; (iii) the efficacy of FRP is an increasing function of the amine (EDB) concentration, in contrast to that of CP having an opposite dependence; (iv) the consumption rate of BT3 in the BT3/ Iod/EDB system is slower than that of the BT3/Iod system due to photoredox catalytic cycle, and the larger initiator regeneration (RGE)
in the three-component system. A comprehensive model is also proposed that the CE (for both FRP and CP) is governed by (NjKjbI), whereas more complex formulas are developed; where Kj is an effective rate constant proportional to the electron transfer quantum yield, and the combined effects of other coupling rate constants; b is an effective absorption coefficient given by the light absorption and excited state quantum yield.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 4013
Author(s):  
Jui-Teng Lin ◽  
Jacques Lalevee ◽  
Hsia-Wei Liu

This article presents, for the first time, the kinetics and the general features of a photopolymerization system (under visible light), copper-complex/Iodonium/triethylamine/gold-chloride (orA/B/N/G), with initial concentrations of A0, B0, N0 and G0, based on the proposed mechanism of Tar et al. Analytic formulas were developed to explore the new features, including: (i) both free radical photopolymerization (FRP) efficacy and the production of nanogold (NG), which are proportional to the relative concentration ratios of (A0 + B0 + N0)/G0 and may be optimized for maximum efficacy; (ii) the two competing procedures of NG production and the efficacy of FRP, which can be tailored for an optimal system with nanogold in the polymer matrix; (iii) the FRP efficacy, which is contributed by three components given by the excited state of copper complex (T), and the radicals (R and S) produced by iodonium and amine, respectively; (iv) NG production, which is contributed by the coupling of T and radical (S) with gold ion; and (v) NG production, which has a transient state proportional to the light intensity and the concentration ratio A0/G0) + (N0/(K’M0), but also a steady-state independent of the light intensity.


2018 ◽  
Vol 52 (2) ◽  
pp. 397-406
Author(s):  
A. B. Ismailov ◽  
G. P. Urbanavichus

The lichens and lichenicolous fungi of high mountainous landscapes of Samurskiy Ridge were studied in altitudinal range 2400–3770 m a. s. l. for the first time and 112 species are recorded. Among them 33 species, 10 genera (Arthrorhaphis, Baeomyces, Calvitimela, Epilichen, Lambiella, Psorinia, Rufoplaca, Sagedia, Sporastatia, Tremolecia) and 4 families (Anamylopsoraceae, Arthrorhaphidaceae, Baeomycetaceae, Hymeneliaceae) are new for Dagestan, six species (Buellia uberior, Carbonea atronivea, Lecanora atrosulphurea, Lecidea fuliginosa, L. swartzioidea, Rhizoplaca subdiscrepans) are reported for the first time for the Greater Caucasus and two species (Acarospora subpruinata and Rhizocarpon postumum) — for the North Caucasus. Most of the new findings were collected from 3500–3770 m a. s. l.


2020 ◽  
Vol 147 (2) ◽  
pp. 153-163
Author(s):  
Kirsten Dzwiza

SummaryThere are only a few sequences of ancient magic signs known to us today that have been preserved on multiple artefacts. A previously unnoticed sequence of 17 signs on a gem in the Museum of Fine Arts in Vienna occurs with minor but significant variations on two other gems in the State Museum of Egyptian Art in Munich. The Viennese gem is dated to the 16th century and is documented as a drawing in a 17th century publication. The first Munich gem has been assigned to the Graeco-Roman period. The second gem, which, according to the inventory card of the museum, also belongs to the Graeco-Roman period, is published here for the first time. A comparative study of the three gems and the drawing has lead to a number of new findings, including the re-dating of the Munich gems.


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 410
Author(s):  
Irene Sánchez-Gavilán ◽  
Esteban Ramírez ◽  
Vicenta de la Fuente

Many halophytes have great nutritional and functional potential, providing chemical compounds with biological properties. Salicornia patula Duval-Jouve is a common euhalophyte from saline Mediterranean territories (Spain, Portugal, France, and Italy). In the present work we quantified for the first time the bioactive compounds in S. patula (total phenolic compounds and fatty acids), from Iberian Peninsula localities: littoral-coastal Tinto River basin areas (southwest Spain, the Huelva province), and mainland continental territories (northwest and central Spain, the Valladolid and Madrid provinces). Five phenolic acids including caffeic, coumaric, veratric, salicylic, and transcinnamic have been found with differences between mainland and coastal saltmarshes. S. patula contain four flavonoids: quercetin-3-O-rutinoside, kaempferol/luteolin, apigenin 7-glucoside, and pelargonidin-3-O-rutinoside. These last two glycosylated compounds are described for the first time in this genus of Chenopodiaceae. The fatty acid profile described in S. patula stems contains palmitic, oleic, and linoleic acids in high concentrations, while stearic and long-chain fatty acids were detected in low amounts. These new findings confirm that S. patula is a valuable source of bioactive compounds from Mediterranean area.


2021 ◽  
Author(s):  
Jacques Lalevée ◽  
Fatima Hammoud ◽  
Mahmoud Rahal ◽  
Julien Egly ◽  
Fabrice Morlet-Savary ◽  
...  

The investigation of copper-iodide cubane derivatives as new co-initiators for the free radical polymerization (FRP) of acrylate monomers under mild irradiation conditions is described for the first time here. These...


2020 ◽  
Vol 41 (2) ◽  
pp. 213-220
Author(s):  
Fermín Del Egido ◽  
Patricio Bariego ◽  
Alberto Rodríguez ◽  
María Santos Vicente

We provide new records and notes on 25 protected and/or threatened vascular plant species in Castilla y León. Some of them illustrate not only new findings but also an interesting expansion of their geographic range. Eight taxa are reported for the first time in some provinces, while eleven of them were two or three times previously reported.


Zootaxa ◽  
2021 ◽  
Vol 4949 (2) ◽  
pp. 381-397
Author(s):  
S. PRASANTH NARAYANAN ◽  
S. SATHRUMITHRA ◽  
R. ANUJA ◽  
G. CHRISTOPHER ◽  
A.P. THOMAS ◽  
...  

Three new species of Moniligaster Perrier, 1872, namely M. bahli Narayanan & Julka, sp. nov., M. blakemorei Narayanan & Julka, sp. nov. and M. keralensis Narayanan & Julka, sp. nov. are described from materials collected from the Indian state of Kerala. Moniligaster cernosvitovi Gates, 1962, Moniligaster horsti Gates, 1940, Moniligaster michaelseni Gates, 1940 and Moniligaster stephensoni Gates, 1940 are recorded for the first time from the state. With the new findings, a total of 10 Moniligaster species are known from Kerala. Moniligaster species are restricted to southern peninsular India, except Moniligaster ivaniosi Manazhy, 2011, decribed from the Andaman Islands, outside the currently known distributional range of the genus. Hence we critically reviewed the original description and reinvestigated the holotype. As a result, Moniligaster ivaniosi is considered a junior synonym of Drawida nepalensis Michaelsen, 1907. 


Biomedicines ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 319
Author(s):  
Marie-Paule Lefranc ◽  
Gérard Lefranc

IMGT®, the international ImMunoGeneTics® information system founded in 1989 by Marie-Paule Lefranc (Université de Montpellier and CNRS), marked the advent of immunoinformatics, a new science at the interface between immunogenetics and bioinformatics. For the first time, the immunoglobulin (IG) or antibody and T cell receptor (TR) genes were officially recognized as ‘genes’ as well as were conventional genes. This major breakthrough has allowed the entry, in genomic databases, of the IG and TR variable (V), diversity (D) and joining (J) genes and alleles of Homo sapiens and of other jawed vertebrate species, based on the CLASSIFICATION axiom. The second major breakthrough has been the IMGT unique numbering and the IMGT Collier de Perles for the V and constant (C) domains of the IG and TR and other proteins of the IG superfamily (IgSF), based on the NUMEROTATION axiom. IMGT-ONTOLOGY axioms and concepts bridge genes, sequences, structures and functions, between biological and computational spheres in the IMGT® system (Web resources, databases and tools). They provide the IMGT Scientific chart rules to identify, to describe and to analyse the IG complex molecular data, the huge diversity of repertoires, the genetic (alleles, allotypes, CNV) polymorphisms, the IG dual function (paratope/epitope, effector properties), the antibody humanization and engineering.


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