Interplay between two radical species in the formation of periodic patterns during a polymerization reaction

2020 ◽  
Vol 22 (38) ◽  
pp. 21672-21677
Author(s):  
Daisuke Sato ◽  
Masaki Itatani ◽  
Jun Matsui ◽  
Kei Unoura ◽  
Hideki Nabika
Keyword(s):  
Polymerization Reaction ◽  
Periodic Patterns ◽  
Radical Species ◽  
Periodic Precipitation

Interplay between initiator and monomer radicals forms periodic precipitation of polymers.

Forced Periodic and Quasi-Periodic Patterns in Anisotropic Systems

1996 ◽  
Vol 6 (2) ◽  
pp. 305-328 ◽  
Author(s):  
Atsushi Ogawa ◽  
Walter Zimmermann ◽  
Kyozi Kawasaki ◽  
Toshihiro Kawakatsu
Keyword(s):  
Periodic Patterns ◽  
Anisotropic Systems

Kinetics of the Thermal Disappearance of Radicals Formed During the Radiolysis of Aspartic Acid

2009 ◽  
Vol 59 (12) ◽  
Author(s):  
Mihai Contineanu ◽  
iulia Contineanu ◽  
Ana Neacsu ◽  
Stefan Perisanu
Keyword(s):  
Thermal Resistance ◽  
Aspartic Acid ◽  
Room Temperature ◽  
Esr Spectra ◽  
Complex Mechanism ◽  
Radical Species ◽  
Mechanisms Of Formation ◽  
Kinetics Of

The radiolysis of the isomers L-, D- and DL- of the aspartic acid, in solid polycrystalline state, was investigated at room temperature. The analysis of their ESR spectra indicated the formation of at least two radicalic entities. The radical, identified as R3, resulting from the deamination of the acid, exhibits the highest concentration and thermal resistance. Possible mechanisms of formation of three radical species are suggested, based also on literature data. The kinetics of the disappearance of radical R3 indicated a complex mechanism. Three possible variants were suggested for this mechanism.

High-Frequency Periodic Patterns Driven by Non-Radiative Fields Coupled with Marangoni Convection Instabilities on Laser-Excited Surfaces

2019 ◽  
Author(s):  
Anton Rudenko ◽  
Anthony Abou-Saleh ◽  
Florent Pigeon ◽  
Cyril Mauclair ◽  
Florence Garrelie, Prof. ◽  
...  
Keyword(s):  
High Frequency ◽  
Marangoni Convection ◽  
Periodic Patterns

Gravity Effect on the Formation of Periodic Precipitation Patterns

2000 ◽  
Vol 65 (9) ◽  
pp. 1438-1442 ◽  
Author(s):  
Vladislav Holba ◽  
Frederik Fusek
Keyword(s):  
Gravitational Field ◽  
Spatial Arrangement ◽  
Experimental Results ◽  
Single Sample ◽  
Gravity Effect ◽  
Periodic Precipitation ◽  
Precipitation Patterns ◽  
Liesegang Bands

The effect of gravity on the formation of Liesegang patterns of Ag2Cr2O7in gelatin and that of PbI2in agar was investigated. Spatial arrangement of Liesegang bands was measured in the parallel and antiparallel orientation to the gravitational field in a single sample with all other parameters kept fixed. The experimental results are discussed in terms of the prenucleation theory of periodic precipitation.

scholarly journals Adsorption Capacity and Selectivity of Molecularly Imprinted Polymers towards β-Sitosterol

2019 ◽  
Vol 31 (11) ◽  
pp. 2527-2531
Author(s):  
St. Fauziah ◽  
N.H. Soekamto ◽  
P. Budi ◽  
P. Taba
Keyword(s):  
Adsorption Capacity ◽  
Molecularly Imprinted Polymers ◽  
Solid Phase ◽  
Polymerization Reaction ◽  
Molecularly Imprinted ◽  
Imprinted Polymers ◽  
Sample Extract ◽  
Uv Visible ◽  
Adsorption Desorption ◽  
Isothermal Equation

Molecularly imprinted polymers (MIP) as an adsorbent has been synthesized using β-sitosterol as molecule template on free radical polymerization reaction. The capacity and selectivity of the adsorption from MIP to β-sitosterol was studied in this study. The β-sitosterol concentration in the adsorption-desorption test and the MIP selectivity test were analyzed by UV-visible and HPLC. The MIP obtained from the synthesis results in a high adsorption capacity. Based on the Freundlich adsorption isothermal equation, the adsorption capacity (k) was found to be 1.24 mg/g. The MIP can adsorb 100 % β-sitosterol while cholesterol was only 3 %. The MIP is most selective to β-sitosterol, therefore, has high potential to apply as adsorbent at solid phase extraction method to isolate β-sitosterol from sample extract.

scholarly journals Influence of the Active Layer Structure on the Photovoltaic Performance of Water-Soluble Polythiophene-Based Solar Cells

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1640
Author(s):  
Massimiliano Lanzi ◽  
Debora Quadretti ◽  
Martina Marinelli ◽  
Yasamin Ziai ◽  
Elisabetta Salatelli ◽  
...  
Keyword(s):  
Solar Cells ◽  
Layer Structure ◽  
Photovoltaic Performance ◽  
Phase Segregation ◽  
Water Soluble ◽  
Polymerization Reaction ◽  
Fullerene Derivative ◽  
C60 Fullerene ◽  
Photovoltaic Efficiency ◽  
Single Material

A new side-chain C60-fullerene functionalized thiophene copolymer bearing tributylphosphine-substituted hexylic lateral groups was successfully synthesized by means of a fast and effective post-polymerization reaction on a regioregular ω-alkylbrominated polymeric precursor. The growth of the polymeric intermediate was followed by NMR spectrometry in order to determine the most convenient reaction time. The obtained copolymer was soluble in water and polar solvents and was used as a photoactive layer in single-material organic photovoltaic (OPV) solar cells. The copolymer photovoltaic efficiency was compared with that of an OPV cell containing a water-soluble polythiophenic homopolymer, functionalized with the same tributylphosphine-substituted hexylic side chains, in a blend with a water-soluble C60-fullerene derivative. The use of a water-soluble double-cable copolymer made it possible to enhance the control on the nanomorphology of the active blend, thus reducing phase-segregation phenomena, as well as the macroscale separation between the electron acceptor and donor components. Indeed, the power conversion efficiency of OPV cells based on a single material was higher than that obtained with the classical architecture, involving the presence of two distinct ED and EA materials (PCE: 3.11% vs. 2.29%, respectively). Moreover, the synthetic procedure adopted to obtain single material-based cells is more straightforward and easier than that used for the preparation of the homopolymer-based BHJ solar cell, thus making it possible to completely avoid the long synthetic pathway which is required to prepare water-soluble fullerene derivatives.

scholarly journals Short-Pulse Lasers: A Versatile Tool in Creating Novel Nano-/Micro-Structures and Compositional Analysis for Healthcare and Wellbeing Challenges

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 712
Author(s):  
Ahmed Al-Kattan ◽  
David Grojo ◽  
Christophe Drouet ◽  
Alexandros Mouskeftaras ◽  
Philippe Delaporte ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Surface Engineering ◽  
Short Pulse ◽  
Chemical Properties ◽  
Compositional Analysis ◽  
Periodic Patterns ◽  
Laser Ablation In Liquid ◽  
Micro Scale ◽  
Direct Laser ◽  
Contact Free

Driven by flexibility, precision, repeatability and eco-friendliness, laser-based technologies have attracted great interest to engineer or to analyze materials in various fields including energy, environment, biology and medicine. A major advantage of laser processing relies on the ability to directly structure matter at different scales and to prepare novel materials with unique physical and chemical properties. It is also a contact-free approach that makes it possible to work in inert or reactive liquid or gaseous environment. This leads today to a unique opportunity for designing, fabricating and even analyzing novel complex bio-systems. To illustrate this potential, in this paper, we gather our recent research on four types of laser-based methods relevant for nano-/micro-scale applications. First, we present and discuss pulsed laser ablation in liquid, exploited today for synthetizing ultraclean “bare” nanoparticles attractive for medicine and tissue engineering applications. Second, we discuss robust methods for rapid surface and bulk machining (subtractive manufacturing) at different scales by laser ablation. Among them, the microsphere-assisted laser surface engineering is detailed for its appropriateness to design structured substrates with hierarchically periodic patterns at nano-/micro-scale without chemical treatments. Third, we address the laser-induced forward transfer, a technology based on direct laser printing, to transfer and assemble a multitude of materials (additive structuring), including biological moiety without alteration of functionality. Finally, the fourth method is about chemical analysis: we present the potential of laser-induced breakdown spectroscopy, providing a unique tool for contact-free and space-resolved elemental analysis of organic materials. Overall, we present and discuss the prospect and complementarity of emerging reliable laser technologies, to address challenges in materials’ preparation relevant for the development of innovative multi-scale and multi-material platforms for bio-applications.

scholarly journals Study of the Physical Behavior of a New Composite Material Based on Fly Ash from the Combustion of Coal in an Ultra-Supercritical Thermal Power Plant

2021 ◽  
Vol 5 (6) ◽  
pp. 151
Author(s):  
Mustapha El Kanzaoui ◽  
Chouaib Ennawaoui ◽  
Saleh Eladaoui ◽  
Abdelowahed Hajjaji ◽  
Abdellah Guenbour ◽  
...  
Keyword(s):  
Composite Material ◽  
Fly Ash ◽  
Power Plant ◽  
High Performance ◽  
Thermal Power ◽  
Recovery Process ◽  
Industrial Wastes ◽  
Raw Material ◽  
Polymerization Reaction ◽  
High Performance Composite

Given the amount of industrial waste produced and collected in the world today, a recycling and recovery process is needed. The study carried out on this subject focuses on the valorization of one of these industrial wastes, namely the fly ash produced by an ultra-supercritical coal power plant. This paper describes the use and recovery of fly ash as a high percentage reinforcement for the development of a new high-performance composite material for use in various fields. The raw material, fly ash, comes from the staged combustion of coal, which occurs in the furnace of an ultra-supercritical boiler of a coal-fired power plant. Mechanical compression, thermal conductivity, and erosion tests are used to study the mechanical, thermal, and erosion behavior of this new composite material. The mineralogical and textural analyses of samples were characterized using Scanning Electron Microscopy (SEM). SEM confirmed the formation of a new composite by a polymerization reaction. The results obtained are very remarkable, with a high Young’s modulus and a criterion of insulation, which approves the presence of a potential to be exploited in the different fields of materials. In conclusion, the composite material presented in this study has great potential for building material and could represent interesting candidates for the smart city.

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