scholarly journals Fast and Slow Time Regimes of Fluorescence Quenching in Conjugated Polyfluorene−Fluorenone Random Copolymers:  The Role of Exciton Hopping and Dexter Transfer along the Polymer Backbone

2006 ◽  
Vol 39 (4) ◽  
pp. 1598-1606 ◽  
Author(s):  
Fernando B. Dias ◽  
Matti Knaapila ◽  
Andrew P. Monkman ◽  
Hugh D. Burrows
Keyword(s):  
Fluorescence Quenching ◽  
Random Copolymers ◽  
Slow Time ◽  
Polymer Backbone

scholarly journals Detection of nitroaromatic vapours with diketopyrrolopyrrole thin films: exploring the role of structural order and morphology on thin film properties and fluorescence quenching efficiency

2015 ◽  
Vol 51 (6) ◽  
pp. 1143-1146 ◽  
Author(s):  
Monika Warzecha ◽  
Jesus Calvo-Castro ◽  
Alan R. Kennedy ◽  
Alisdair N. Macpherson ◽  
Kenneth Shankland ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Fluorescence Quenching ◽  
Optical Detection ◽  
Film Properties ◽  
Structural Order ◽  
Quenching Efficiency ◽  
First Time

Sensitive optical detection of nitroaromatic vapours with diketopyrrolopyrrole thin films is reported for the first time.

scholarly journals The role of substance P as a neurotransmitter in the reflexes of slow time courses in the neonatal rat spinal cord

1985 ◽  
Vol 84 (3) ◽  
pp. 663-673 ◽  
Author(s):  
Hiroyuki Akagi ◽  
Shiro Konishi ◽  
Masanori Otsuka ◽  
Mitsuhiko Yanagisawa
Keyword(s):  
Spinal Cord ◽  
Substance P ◽  
Neonatal Rat ◽  
Rat Spinal Cord ◽  
Slow Time ◽  
Time Courses

Role of solvent polarity on fluorescence quenching of 3MOCE in binary solvent mixtures

2020 ◽  
Author(s):  
S. Vaijayanthimala ◽  
Kalpana Sharma ◽  
Raveendra Melavanki ◽  
P. Bhavya ◽  
U. Meghana ◽  
...  
Keyword(s):  
Fluorescence Quenching ◽  
Solvent Polarity ◽  
Binary Solvent ◽  
Solvent Mixtures ◽  
Binary Solvent Mixtures ◽  
Role Of Solvent

scholarly journals Spatiotemporal pH Heterogeneity as a Promoter of Cancer Progression and Therapeutic Resistance

Cancers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1026 ◽  
Author(s):  
David E. Korenchan ◽  
Robert R. Flavell
Keyword(s):  
Cancer Cells ◽  
Cancer Progression ◽  
Co2 Exchange ◽  
Therapeutic Resistance ◽  
Slow Time ◽  
Phenotypic Changes ◽  
Ph Buffering ◽  
Available Technology ◽  
Kinetics Of

Dysregulation of pH in solid tumors is a hallmark of cancer. In recent years, the role of altered pH heterogeneity in space, between benign and aggressive tissues, between individual cancer cells, and between subcellular compartments, has been steadily elucidated. Changes in temporal pH-related processes on both fast and slow time scales, including altered kinetics of bicarbonate-CO2 exchange and its effects on pH buffering and gradual, progressive changes driven by changes in metabolism, are further implicated in phenotypic changes observed in cancers. These discoveries have been driven by advances in imaging technologies. This review provides an overview of intra- and extracellular pH alterations in time and space reflected in cancer cells, as well as the available technology to study pH spatiotemporal heterogeneity.

scholarly journals Comparative Experimental and Theoretical Study of Mg, Al and Zn Aryloxy Complexes in Copolymerization of Cyclic Esters: The Role of the Metal Coordination in Formation of Random Copolymers

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2273
Author(s):  
Ilya Nifant’ev ◽  
Pavel Komarov ◽  
Valeriya Ovchinnikova ◽  
Artem Kiselev ◽  
Mikhail Minyaev ◽  
...  
Keyword(s):  
Density Functional ◽  
Rational Design ◽  
Qualitative Difference ◽  
Random Copolymers ◽  
Coordination Polymerization ◽  
Polymer Backbone ◽  
Catalytic Behavior ◽  
Cyclic Esters ◽  
Dft Modeling ◽  
The Density Functional Theory

Homogeneity of copolymers is a general problem of catalytic coordination polymerization. In ring-opening polymerization of cyclic esters, the rational design of the catalyst is generally applied to solve this problem by the equalization of the reactivities of comonomers—however, it often leads to a reduction of catalytic activity. In the present paper, we studied the catalytic behavior of BnOH-activated complexes (BHT)Mg(THF)2nBu (1), (BHT)2AlMe (2) and [(BHT)ZnEt]2 (3), based on 2,6-di-tert-butyl-4-methylphenol (BHT-H) in homo- and copolymerization of L-lactide (lLA) and ε-caprolactone (εCL). Even at 1:5 lLA/εCL ratio Mg complex 1 catalyzed homopolymerization of lLA without involving εCL to the formation of the polymer backbone. On the contrary, Zn complex 3 efficiently catalyzed random lLA/εCL copolymerization; the presence of mono-lactate subunits in the copolymer chain clearly pointed to the transesterification mechanism of copolymer formation. Both epimerization and transesterification side processes were analyzed using the density functional theory (DFT) modeling that confirmed the qualitative difference in catalytic behavior of 1 and 3: Mg and Zn complexes demonstrated different types of preferable coordination on the PLA chain (k2 and k3, respectively) with the result that complex 3 catalyzed controlled εCL ROP/PLA transesterification, providing the formation of lLA/εCL copolymers that contain mono-lactate fragments separated by short oligo(εCL) chains. The best results in the synthesis of random lLA/εCL copolymers were obtained during experiments on transesterification of commercially available PLLA, the applicability of 3/BnOH catalyst in the synthesis of random copolymers of εCL with methyl glycolide, ethyl ethylene phosphonate and ethyl ethylene phosphate was also demonstrated.

Continuous Cooling Curves Diagrams of Propene/Ethylene Random Copolymers. The Role of Ethylene Counits in Mesophase Development

2010 ◽  
Vol 43 (6) ◽  
pp. 2890-2896 ◽  
Author(s):  
Dario Cavallo ◽  
Fiorenza Azzurri ◽  
Roberto Floris ◽  
Giovanni C. Alfonso ◽  
Luigi Balzano ◽  
...  
Keyword(s):  
Random Copolymers ◽  
Cooling Curves ◽  
Continuous Cooling
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