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Topic Review
2-Oxocarboxylic Acids
Atmospheric organic aerosols play a major role in climate, demanding a better understanding of their formation mechanisms by contributing multiphase chemical reactions with the participation of water. The sunlight driven aqueous photochemistry of small 2-oxocarboxylic acids is a potential major source of organic aerosol, which prompted the investigations into the mechanisms of glyoxylic acid and pyruvic acid photochemistry reviewed here. While 2-oxocarboxylic acids can be contained or directly created in the particles, the majorities of these abundant and available molecules are in the gas phase and must first undergo the surface uptake process to react in, and on the surface, of aqueous particles.
  • 1.1K
  • 02 Jul 2023
Topic Review
A Labile Metallo-Porphyrin as Tool to Control J-Aggregates Chiroptical Properties
The zinc(II) metal derivative of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS4) is quite labile and readily demetallates under acidic conditions, affording the parent diacid porphyrin in a monomeric form. The rate of this process is first order on [ZnTPPS4] and second order on [H+], allowing a precise control of the monomer release in solution. Under high ionic strength, this latter species is able to self-assemble into J-aggregates, whose kinetics of growth are largely modulated by pH. The aggregation kinetics have been treated according to a well-established model, in which the formation of an initial nucleus is the rate determining step preceding the autocatalytic growth of the whole assembly. The extinction spectra of the aggregates suggest the occurrence of a dipolar coupling mechanism very similar to that operating in metal nanoparticles. Spontaneous symmetry breaking takes place in these aggregates as evidenced by unusual circular dichroism spectra. The intensity and sign of the effect is controlled by the aggregation rate and therefore can be tuned through a proper choice of initial conditions.
  • 1.0K
  • 15 Jul 2020
Topic Review
Ab Initio Molecular Dynamics NMR
Molecular dynamics (MD) simulation is a well-established technique used for the study of various chemical substances and mixtures in any state of matter and almost at any temperature and pressure conditions. Its combination with QM NMR calculations can significantly increase the accuracy of the results.
  • 616
  • 27 Apr 2021
Biography
Aimé Argand
François Pierre Ami Argand (5 July 1750 – 24 October 1803[1]) was a Genevan physicist and chemist. He invented the Argand lamp, a great improvement on the traditional oil lamp.[2] Francois Pierre Ami Argand was born in Geneva, Switzerland, the ninth of ten children. His father was a watchmaker, who intended for him to enter the clergy. However, he had an aptitude more for science, and beca
  • 569
  • 14 Nov 2022
Topic Review
Appications of Natural Clinoptilolites Based on Ion Exchange
There are many natural zeolites, of which a small number, including clinoptilolite, chabazite, mordenite, erionite, ferrierite, and phillipsite offer the greatest promise for industrial applications. Natural clinoptilolites have been the subject for different modifications in order to improve their use potentialities, where the ion exchange property has been a key role for their different applications. Application of ion exchange to modify clinoptilolites, cation selection, mono- and polycationic exchange to create new functional materials for specific applications are key issues.
  • 543
  • 03 Jan 2023
Topic Review
Application of High-Entropy Alloys in SOFC Technology
The mechanisms of the stabilization of a high-entropy state in such materials, as well as the effect of structural and charge factors on the stability of the resulting homogeneous solid solution are performed. An introduction to the synthesis methods for HEAs (high-entropy alloys) is given. 
  • 548
  • 11 Jan 2023
Topic Review
Application of Quantum Mechanics/Molecular Mechanics Methodologies to Metalloproteins
The multiscaling quantum mechanics/molecular mechanics (QM/MM) approach was introduced in 1976, while the extensive acceptance of this methodology started in the 1990s. The combination of QM/MM approach with molecular dynamics (MD) simulation, otherwise known as the QM/MM/MD approach, is a powerful and promising tool for the investigation of chemical reactions’ mechanism of complex molecular systems, drug delivery, properties of molecular devices, organic electronics, etc. Applications of the QM/MM methodologies on metalloproteins are presented.  
  • 957
  • 05 May 2022
Topic Review
Application of Supercritical Fluids in COVID-19
Even though years have passed since the emergence of COVID-19, the research for novel or repositioned medicines from a natural source or chemically synthesized is still an unmet clinical need. There are three main applications of the supercritical fluids in this field: (i) drug micronization, (ii) supercritical fluid extraction of bioactives and (iii) sterilization. The supercritical fluids micronization techniques can help to improve the aqueous solubility and oral bioavailability of drugs, and consequently, the need for lower doses to elicit the same pharmacological effects can result in the reduction in the dose administered and adverse effects. In addition, micronization between 1 and 5 µm can aid in the manufacturing of pulmonary formulations to target the drug directly to the lung. Supercritical fluids also have enormous potential in the extraction of natural bioactive compounds, which have shown remarkable efficacy against COVID-19. Finally, the successful application of supercritical fluids in the inactivation of viruses opens up an opportunity for their application in drug sterilization and in the healthcare field.
  • 432
  • 29 Nov 2022
Topic Review
Applications of Coacervates
Coacervates are one of the most intriguing systems in colloid chemistry. The term comes from the Latin words “co” (jointly) and “acerv” (a mound). Coacervation is a phenomenon in which a colloidal solution gets separated into colloid-rich and colloid-poor phases.
  • 2.1K
  • 15 Sep 2022
Topic Review
Applications of Cyclodextrins
Due to their unique structural, physical and chemical properties, cyclodextrins and their derivatives have been of great interest to scientists and researchers in both academia and industry for over a century. Many of the industrial applications of cyclodextrins have arisen from their ability to encapsulate, either partially or fully, other molecules, especially organic compounds. Cyclodextrins are non-toxic oligopolymers of glucose that help to increase the solubility of organic compounds with poor aqueous solubility, can mask odors from foul-smelling compounds, and have been widely studied in the area of drug delivery. 
  • 5.6K
  • 29 Mar 2022
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