Intriguing photophysical aspects of nitro substituted 2-(2′-hydroxyphenyl)benzothiazole (HBT) derivative: AIE in non-polar media?

2021 ◽  
Vol 541 ◽  
pp. 111032
Author(s):  
Arghyadeep Bhattacharyya ◽  
Nikhil Guchhait
Keyword(s):  
Polar Media

Influence of solvent polarity on the dual fluorescence of p-N,N-dimethylaminobenzonitrile: An AM1 theoretical study

1990 ◽  
Vol 55 (8) ◽  
pp. 1891-1895 ◽  
Author(s):  
Peter Ertl
Keyword(s):  
Excited State ◽  
Theoretical Study ◽  
Solvent Polarity ◽  
Semiempirical Method ◽  
Dual Fluorescence ◽  
Long Wavelength ◽  
Polar Media ◽  
Wavelength Emission ◽  
Ground State Geometry ◽  
Influence Of Solvent

Twisting of the NMe2 group in p-N,N-dimethylaminobenzonitrile (DMABN) was investigated using AM1 semiempirical method with configuration interaction. Effect of polar media was considered by placing + and - charge centers ("sparkles") at appropriate places opposite the molecule. Optimized ground state geometry of DMABN is slightly twisted with the lowest vertical excited state of 1B character. As the polarity of media increases and/or the - NMe2 group twists, the symmetric 1A excited state having considerable charge separation becomes energetically favorable. Anomalous long-wavelength emission of DMABN comes from this state.

(Thio)Urea-Functionalized Cavitands as Excellent Receptors for Organic Anions in Polar Media

2004 ◽  
Vol 69 (5) ◽  
pp. 1137-1148 ◽  
Author(s):  
Gennady V. Oshovsky ◽  
Willem Verboom ◽  
David N. Reinhoudt
Keyword(s):  
Binding Sites ◽  
Binding Constants ◽  
Organic Anions ◽  
Isothermal Microcalorimetry ◽  
Polar Media

Ureidocavitand 1 and thioureidocavitand 2 bind in CH3CN organic anions such as acetate, propionate, butyrate, etc. with K values of 2-8 × 105 l mol-1 and 2-9 × 106 l mol-1, respectively, as was determined with isothermal microcalorimetry (ITC). Bringing together four (thio)urea binding sites on a molecular platform gives rise to about 2000 times higher binding constants, compared with those of the corresponding single binding sites. Glucose- and galactose-containing thioureidocavitands 5 and 6 bind acetate in 1:1 CH3CN/water with a K-value of 2.15 × 103 l mol-1.

scholarly journals METHODS FOR THE STUDY OF SMALL PHAGOSOMES AND THEIR RELATIONSHIP TO LYSOSOMES WITH HORSERADISH PEROXIDASE AS A "MARKER PROTEIN"

1967 ◽  
Vol 15 (7) ◽  
pp. 375-380 ◽  
Author(s):  
WERNER STRAUS
Keyword(s):  
Acid Phosphatase ◽  
Low Temperature ◽  
Horseradish Peroxidase ◽  
Acid Medium ◽  
Tissue Section ◽  
Double Staining ◽  
Marker Protein ◽  
Polar Media ◽  
The Stability ◽  
Blue Reaction

Small phagosomes (micropinocytic vesicles and vacuoles) which had taken up injected horseradish peroxidase were identified by staining for peroxidase with benzidine and H2O2. Because of the small size of the granules and the possibility of artifacts, previously described procedures had to be modified in several respects. Prefixation of the tissue by perfusion at 37°C prevented artifacts of diffusion and adsorption of peroxidase. The blue product of the reaction of peroxidase with benzidine in the small phagosomes was preserved and fading to brown was prevented by cooling the tissue section to –10° to –15°C during its processing through polar media. The blue reaction product was stable as soon as the section was transferred to an apolar medium. Small phagosomes were visualized together with lysosomes and phago-lysosomes in the same cells by double staining for acid phosphatase and peroxidase in contrasting colors. The incubation for acid phosphatase was performed at 4°C since low temperature increased the stability of peroxidase in the acid medium. Factors which form the basis for other improvements of the procedure are discussed.

ChemInform Abstract: Improved Addition of Phenyllithium to Hindered Ketones by the Use of Non-Polar Media.

ChemInform ◽  
2010 ◽  
Vol 33 (34) ◽  
pp. no-no
Author(s):  
Vincent Lecomte ◽  
Elie Stephan ◽  
Gerard Jaouen
Keyword(s):  
Polar Media

Hydrogen-bonded molecular capsules are stable in polar media

2001 ◽  
pp. 2376-2377 ◽  
Author(s):  
Jerry L. Atwood ◽  
Leonard J. Barbour ◽  
Agoston Jerga
Keyword(s):  
Molecular Capsules ◽  
Polar Media ◽  
Hydrogen Bonded

Ionic effects on Supramolecular Hosts: Solvation and Counter-ion Binding in Polar Media

2021 ◽  
Author(s):  
Nicolas Moreno-Gómez ◽  
Edgar Vargas ◽  
Richard Buchner
Keyword(s):  
Aqueous Solution ◽  
Supramolecular Chemistry ◽  
Ion Binding ◽  
Host Molecules ◽  
Counter Ion ◽  
Polar Media ◽  
Counter Ion Binding ◽  
Ionic Effects

For the progress of synthetic supramolecular chemistry in aqueous solution the design of host molecules soluble in this medium is essential. A possible route is the introduction of ionic residues,...

scholarly journals Fabrication of carbon nanotube-reinforced mortar specimens: evaluation of mechanical and pressure-sensitive properties

2018 ◽  
Vol 188 ◽  
pp. 01019 ◽  
Author(s):  
Evangelia K. Karaxi ◽  
Irene A. Kanellopoulou ◽  
Anna Karatza ◽  
Ioannis A. Kartsonakis ◽  
Costas A. Charitidis
Keyword(s):  
Cementitious Composites ◽  
Mixing Process ◽  
Mechanical And Electrical Properties ◽  
Pressure Sensitive ◽  
Polar Media ◽  
Significant Research ◽  
Multi Walled Carbon Nanotubes ◽  
Carbon Based Nanomaterials ◽  
Walled Carbon Nanotubes ◽  
Carbon Based

Carbon-based nanomaterials are promising reinforcing elements for the development of “smart” self-sensing cementitious composites due to their exceptional mechanical and electrical properties. Significant research efforts have been committed on the synthesis of cement-based composite materials reinforced with carbonaceous nanostructures, covering every aspect of the production process (type of nanomaterial, mixing process, electrode type, measurement methods etc.). In this study, the aim is to develop a well-defined repeatable procedure for the fabrication as well as the evaluation of pressure-sensitive properties of intrinsically self-sensing cementitious composites incorporating carbon- based nanomaterials. Highly functionalized multi-walled carbon nanotubes with increased dispersibility in polar media were used in the development of advanced reinforced mortar specimens which increased their mechanical properties and provided repeatable pressure-sensitive properties.

scholarly journals Thermodynamics of primary antioxidant action of flavonols in polar solvents

2019 ◽  
Vol 12 (1) ◽  
pp. 108-118 ◽  
Author(s):  
Martin Michalík ◽  
Ján Rimarčík ◽  
Vladimír Lukeš ◽  
Erik Klein
Keyword(s):  
Reaction Pathway ◽  
Hydrogen Atom Transfer ◽  
Antioxidant Effect ◽  
Antioxidant Action ◽  
Polar Solvents ◽  
Polar Media ◽  
Primary Antioxidant ◽  
Intramolecular Hydrogen

Abstract Very recently, a report on the antioxidant activity of flavonoids has appeared, where authors concluded that Hydrogen Atom Transfer mechanism represents the thermodynamically preferred mechanism in polar media (https://doi.org/10.1016/j.foodres.2018.11.018). Unfortunately, serious errors in the theoretical part of the paper led to incorrect conclusions. For six flavonols (galangin, kaempferol, quercetin, morin, myricetin, and fisetin), reaction enthalpies related to three mechanisms of the primary antioxidant action were computed. Based on the obtained results, the role of intramolecular hydrogen bonds (IHB) in the thermodynamics of the antioxidant effect is presented. Calculations and the role of solvation enthalpies of proton and electron in the determination of thermodynamically preferred mechanism is also briefly explained and discussed. The obtained results are in accordance with published works considering the Sequential Proton-Loss Electron-Transfer thermodynamically preferred reaction pathway.

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