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Topic Review
Core–Shell Pigments Nanostructure
Uses of novel technologies for improving the durability and lifespan of the construction materials have emerged as viable solutions toward the sustainable future wherein the coating industry plays a significant role in economy growth and better livelihoods. Thus, the continual innovation of various technologies to introduce diverse market products has become indispensable. Properties of materials like color stability under UV, elevated temperatures and aggressive environments, and skid and abrasion resistance are the main challenges faced by commercial coating materials, leading to more demand of natural materials as sustainable agents. Lately, nanostructured core–shell pigments with unique compositions have widely been utilized in composite materials to enhance their properties. Core–shell particles exhibit smart properties and have immense benefits when combined with building materials. 
  • 948
  • 13 Jul 2021
Topic Review
Entropy-Enthalpy Compensations Fold Proteins
 we reveal a protein-folding mechanism based on the entropy-enthalpy compensations that initially driven by laterally hydrophobic collapse among the side-chains of adjacent residues in the sequences of unfolded protein chains. This hydrophobic collapse promotes the formation of the H-bonds within the polypeptide backbone structures through the entropy-enthalpy compensation mechanism, enabling secondary structures and tertiary structures to fold reproducibly following explicit physical folding codes and forces. The temperature dependence of protein folding is thus attributed to the environment dependence of the conformational Gibbs free energy equation. The folding codes and forces in the amino acid sequence that dictate the formation of β-strands and α-helices can be deciphered with great accuracy through evaluation of the hydrophobic interactions among neighboring side-chains of an unfolded polypeptide from a β-strand-like thermodynamic metastable state. The folding of protein quaternary structures is found to be guided by the entropy-enthalpy compensations in between the docking sites of protein subunits according to the Gibbs free energy equation that is verified by bioinformatics analyses of a dozen structures of dimers. Protein folding is therefore guided by multistage entropy-enthalpy compensations of the system of polypeptide chains and water molecules under the solution conditions. 
  • 948
  • 08 Oct 2021
Topic Review
Graphitic Carbon Nitride as a Photocatalyst
Carbon nitride, albeit known for a long time, has been tested as a photocatalyst only since 2009. Extensive searches for reliable visible-light-activated semiconductor photocatalysts revealed the next generation photocatalyst based on a polymeric semiconductor—graphitic carbon nitride.
  • 947
  • 29 Dec 2022
Topic Review
Crosslinking of Electrospun Gelatin Nanofibers
Electrospinning can be used to prepare nanofiber mats from diverse polymers, polymer blends, or polymers doped with other materials. Amongst this broad range of usable materials, biopolymers play an important role in biotechnological, biomedical, and other applications. Biopolymers like gelatin, however, need to be crosslinked for most applications.
  • 946
  • 24 Jun 2021
Topic Review
Nitroaldol Reaction
The Henry Reaction (also referred to as the nitro-aldol reaction) is a classic carbon–carbon bond formation reaction in organic chemistry. Discovered in 1895 by the Belgian chemist Louis Henry (1834-1913), it is the combination of a nitroalkane and an aldehyde or ketone in the presence of a base to form β-Nitro alcohols. This type of reaction is commonly referred to as a "nitro-aldol" reaction (nitroalkane, aldehyde, and alcohol) It is nearly analogous to the aldol reaction that had been discovered 23 years prior that couples two carbonyl compounds to form β-hydroxy carbonyl compounds known as "aldols" (aldehyde and alcohol). The Henry reaction is a useful technique in the area of organic chemistry due to the synthetic utility of its corresponding products, as they can be easily converted to other useful synthetic intermediates. These conversions include subsequent dehydration to yield nitroalkenes, oxidation of the secondary alcohol to yield α-nitro ketones, or reduction of the nitro group to yield β-amino alcohols. Many of these uses have been exemplified in the syntheses of various pharmaceuticals including the β-blocker (S)-propranolol, the HIV protease inhibitor Amprenavir (Vertex 478), and construction of the carbohydrate subunit of the anthracycline class of antibiotics, L-Acosamine. The synthetic scheme of the L-Acosamine synthesis can be found in the Examples section of this article.
  • 946
  • 14 Oct 2022
Topic Review
Salts Hydrates and Composites
Salt hydrates are alloys of salts and water. Salt hydrates display high theoretical energy densities, which are promising materials in thermal energy storage (TES).
  • 946
  • 25 Jan 2022
Topic Review
Cellulosic Ethanol Commercialization
Cellulosic ethanol commercialization is the process of building an industry out of methods of turning cellulose-containing organic matter into cellulosic ethanol for use as a biofuel. Companies, such as Iogen, POET, DuPont, and Abengoa, are building refineries that can process biomass and turn it into bioethanol. Companies, such as Diversa, Novozymes, and Dyadic, are producing enzymes that could enable a cellulosic ethanol future. The shift from food crop feedstocks to waste residues and native grasses offers significant opportunities for a range of players, from farmers to biotechnology firms, and from project developers to investors. As of 2013, the first commercial-scale plants to produce cellulosic biofuels have begun operating. Multiple pathways for the conversion of different biofuel feedstocks are being used. In the next few years, the cost data of these technologies operating at commercial scale, and their relative performance, will become available. Lessons learnt will lower the costs of the industrial processes involved.
  • 945
  • 26 Oct 2022
Topic Review
Amperometric Biosensors and Biofuel Cells
Amperometric biosensors and biofuel cells are mostly based on immobilized enzymes or living cells. Among the many oxidoreductases, glucose oxidase (GOx) is used mostly in biosensor design. The same GOx can be well applied for the development of biofuel cells and self-charging capacitors based on the operation of biofuel cells. 
  • 945
  • 24 Aug 2021
Topic Review
Two-Dimensional MoTe2 Hetero-Phase Homojunctions
Two-dimensional (2D) hetero-phase homojunctions comprise a semiconducting phase of a material as the channel and a metallic phase of the material as electrodes. In particular, MoTe2 exhibits intriguing properties and its phase is easily altered from semiconducting 2H to metallic 1T′ and vice versa, owing to the extremely small energy barrier between these two phases. MoTe2 thus finds potential applications in electronics as a representative 2D material with multiple phases. 
  • 944
  • 19 Jan 2022
Topic Review
Biological Properties of Anthocyanin Pigments in Blood Oranges
Anthocyanins are natural pigments that give a red, purple, and blue color to many plant, flower, fruit, and vegetable species. Their presence within the genus Citrus was first reported in 1916, and it is well-known that the red color of the flesh and rind of blood (red or pigmented) oranges (Citrus sinensis L. Osbeck) is due to the presence of anthocyanins. They are also present in the young shoots, flowers, and peel of lemon (Citrus limon (L.) Burm. f.), citron (Citrus medica L.), and other citrus species. 
  • 944
  • 22 Dec 2022
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