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Topic Review
Solar Cell
The sun is considered a source of clean, renewable energy, and the most abundant. With silicon being the element most used for the direct conversion of solar energy into electrical energy, solar cells are the technology corresponding to the solution of the problem of energy on our planet.
  • 806
  • 16 Aug 2022
Topic Review
Five-Membered Heterocyclic Compounds
Heterocyclic compounds are a class of compounds of natural origin with favorable properties and hence have major pharmaceutical significance. They have an exceptional adroitness favoring their use as diverse smart biomimetics, in addition to possessing an active pharmacophore in a complex structure. This has made them an indispensable motif in the drug discovery field. Heterocyclic compounds are usually classified according to the ring size, type, and the number of heteroatoms present in the ring.
  • 2.7K
  • 16 Aug 2022
Topic Review
Natural Polymeric Carbohydrate-Based Antibiofilm Materials
Natural biopolymers, especially carbohydrates, show excellent material properties, such as mechanical strength, plasticity, and biodegradability. In addition, the anionic charges of hydrophilic polysaccharides (such as sulfate polysaccharides, hyaluronic acid, etc.) allow ionic attraction with metal ions or organic salts, and thereby they achieve antibacterial material properties. These antibacterial materials can be used to make implants for biomedical use. However, in-vivo compatibility remains a major limitation of such polymeric materials. 
  • 480
  • 16 Aug 2022
Topic Review
Mineral-Supported Photocatalysts
Although they are of significant importance for environmental applications, the industrialization of photocatalytic techniques still faces many difficulties, and the most urgent concern is cost control. Natural minerals possess abundant chemical inertia and cost-efficiency, which is suitable for hybridizing with various effective photocatalysts. The use of natural minerals in photocatalytic systems can not only significantly decrease the pure photocatalyst dosage but can also produce a favorable synergistic effect between photocatalyst and mineral substrate. Owing to their unique structures, large surface area, and negatively charged surface, silicate minerals could enhance the adsorption capacity, reduce particle aggregation, and promote photogenerated electron-hole pair separation for hybrid photocatalysts. Moreover, controlling the morphology and structure properties of these materials could have a great influence on their light-harvesting ability and photocatalytic activity. Composed of silica and alumina or magnesia, some silicate minerals possess unique orderly organized porous or layered structures, which are proper templates to modify the photocatalyst framework. The non-silicate minerals (referred to carbonate and carbon-based minerals, sulfate, and sulfide minerals and other special minerals) can function not only as catalyst supports but also as photocatalysts after special modification due to their unique chemical formula and impurities. The dye-sensitized minerals, as another natural mineral application in photocatalysis, are proved to be superior photocatalysts for hydrogen evolution and wastewater treatment. 
  • 350
  • 16 Aug 2022
Topic Review
Nanotube Functionalization
The carbon nanotubes (CNTs) are modified by different routes, such as covalent and non-covalent modification of the outer surface, the substitution of atoms or the filling of CNT channels. Covalent functionalization (adsorption) requires reactive species that can form covalent adducts with the sp2 carbon of CNT. The main advantage of the covalent functionalization of CNTs is that it is stronger than non-covalent interactions, however, it requires damage to the sidewalls. Unlike non-covalent functionalization, it changes the electronic structure, resulting in the irreversible loss of double bonds. These changes can affect conductivity properties and therefore, some applications.
  • 396
  • 16 Aug 2022
Topic Review
Synthesis of 3,4-Dihydropyrimidin(thio)one Containing Scaffold
The interest in 3,4-dihydropyrimidine-2(1H)-(thio)ones is increasing every day, mainly due to their paramount biological relevance. The Biginelli reaction is the classical approach to reaching these scaffolds, although the product diversity suffers from some limitations. In order to overcome these restrictions, two main approaches have been devised. The first one involves the modification of the conventional components of the Biginelli reaction and the second one refers to the postmodification of the Biginelli products. Both strategies have been extensively revised in this manuscript. Regarding the first one, initially, the modification of one of the components was covered. Although examples of modifications of the three of them were described, by far the modification of the keto ester counterpart was the most popular approach, and a wide variety of different enolizable carbonylic compounds were used; moreover, changes in two or the three components were also described, broadening the substitution of the final dihydropyrimidines. Together with these modifications, the use of Biginelli adducts as a starting point for further modification was also a very useful strategy to decorate the final heterocyclic structure.
  • 1.1K
  • 15 Aug 2022
Topic Review
Thiocoumarins
Thiocoumarins are a particular class of coumarins in which one or two of the oxygen atoms are replaced by a sulfur. They are chemically subdivided in three groups: Thiocoumarins, 2-thioxocoumarins, and dithiocoumarins.
  • 492
  • 15 Aug 2022
Topic Review
Lipids in Food Flavor Generation
Lipids in food are a source of essential fatty acids and also play a crucial role in flavor and off-flavor development. Lipids contribute to food flavor generation due to their degradation to volatile compounds during food processing, heating/cooking, and storage and/or interactions with other constituents developed from the Maillard reaction and Strecker degradation, among others. The degradation of lipids mainly occurs via autoxidation, photooxidation, and enzymatic oxidation, which produce a myriad of volatile compounds. The oxidation of unsaturated fatty acids generates hydroperoxides that then further break down to odor-active volatile secondary lipid oxidation products including aldehydes, alcohols, and ketones.
  • 2.6K
  • 15 Aug 2022
Topic Review
Metal Nanoparticles for Environmental Remediation
Environmental pollution deriving from anthropogenic activities is nowadays a serious problem that afflicts our planet and that cannot be neglected. Nanotechnologies and new performing nanomaterials, thanks to their unique features, such as high surface area (surface/volume ratio), catalytic capacity, reactivity and easy functionalization to chemically modulate their properties, represent potential for the development of sustainable, advanced and innovative products/techniques for environmental (bio)remediation. Metal nanoparticles (MNPs; related to metals or noble metals such as M = Pt, Pd, Ni, Ru, Al, Ag, Au, Cu) are nanomaterials with physical and chemical properties that differ from bulk materials due to their small size and high surface-to-volume ratio. 
  • 683
  • 15 Aug 2022
Topic Review
Assessment of Bio-Based Polyurethanes
Among numerous synthetic macromolecules, polyurethane in its different forms has proven its sheer dominance and established a reputation as a reliable and trusted material due to its proficiency in terms of superior properties, which include: high mechanical strength and abrasion resistance, good durability, good adhesion, good thermal stability, excellent chemical and weathering resistance. Synthetic polyurethane materials are non-biodegradable, poisonous, and use petrochemical-based raw materials, which are now depleting, leading to a surge in polyurethane production costs. Enormous kinds of available bio-renewable sources as predecessors for the production of polyols and isocyanates have been explored for the development of “greener” PU materials; these bio-based polyurethanes have significant potential to be used as future PU products, with a partial or total replacement of petroleum-based polyurethanes, due to increasing concern about the environment, their relatively low cost and biodegradability.
  • 1.8K
  • 12 Aug 2022
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