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Topic Review
ZrB2 Nanopowders Solid-State Synthesis
ZrB2 is of particular interest among ultra-high temperature ceramics because it exhibits excellent thermal resistance at high temperature, as well as chemical stability, high hardness, low cost, and good electrical and thermal conductivity, which meet the requirements of high-temperature components of hyper-sonic aircraft in extreme environments. In recent years, the development of ZrB2 powders’ synthesis method has broken through the classification of traditional solid-phase method, liquid-phase method, and gas-phase method, and there is a trend of integration of them. Solid-state synthesis, including the borothermic reduction method, carbothermic reduction method, and metallothermic reduction method, is mostly used because the process is simple and the raw materials are cheap and easily available. 
  • 970
  • 26 Oct 2021
Topic Review
Elongational Flow
Elongational flow is a particular kind of flow involved in many industrially relevant processing operations of thermoplastics (such as fiber spinning, film blowing, foaming and thermoforming) in which the velocity gradient develops in the same direction as the flow itself.
  • 2.7K
  • 26 Oct 2021
Topic Review
Vertical Graphene Growth by PECVD
Vertical graphene, which belongs to nanomaterials, is a very promising tool for improving the useful properties of long-used and proven materials. Since the growth of vertical graphene is different on each base material and has specific deposition setting parameters, it is necessary to examine each base material separately.
  • 554
  • 26 Oct 2021
Topic Review
Silicon Field Effect Transistors (FET)
Highly sensitive and selective gas and volatile organic compound (VOC) sensor platforms with fast response and recovery kinetics are in high demand for environmental health monitoring, industry, and medical diagnostics. Among the various categories of gas sensors studied to date, field effect transistors (FETs) have proved to be an extremely efficient platform due to their miniaturized form factor, high sensitivity, and ultra-low power consumption. Despite the advent of various kinds of new materials, silicon (Si) still enjoys the advantages of excellent and reproducible electronic properties and compatibility with complementary metal–oxide–semiconductor (CMOS) technologies for integrated multiplexing and signal processing.
  • 1.9K
  • 26 Oct 2021
Topic Review
Interactions between Atmospheric Oxygen and MoS2 Crystals
MoS2 belongs to a class of transition metal dichalcogenides (TMDCs). TMDCs share a common formula MeX2, where Me is a transition metal element from group four (Ti, Zr, Hf), five (V, Nb or Ta) or six (Mo, W), and X is a chalcogen (S, Se or Te). Their crystalline structure comprises an inner Me layer sandwiched by two X layers. Herein, thermal oxidation of the microscopic MoS2 flakes is reviewed. An impact of relative humidity is also mentioned.
  • 556
  • 26 Oct 2021
Topic Review
The Jahn-Teller Effects
The fundamental property of a polyatomic system to undergo spontaneous symmetry breaking was first formulated by L. Landau in 1934 as follows: the configuration of any nonlinear polyatomic system in a degenerate electronic state undergoes spontaneous distortions that remove the degeneracy. This groundbreaking idea, appended with proof, was published by H. Jahn and E. Teller, resulting in what is presently known as the Jahn-Teller effect (JTE). Since then, many extensions of this groundbreaking idea were revealed and developed. Presently, four types of electronic structures that lead to spontaneous symmetry breaking are revealed: in addition to electronic degeneracy resulting in the proper Jahn-Teller effect, two or more close in energy (pseudodegenerate) electronic states may lead to similar instability and distortions, called the pseudo-JTE (PJTE), and the same spontaneous distortion effects may take place when there is neither degeneracy, nor pseudodegeneracy in the fground state of the high-symmetry configuration, but a strong JTE or pseudo-JTE take place in a low-lying excited state, that penetrates the ground state, distorting the system; these are the hidden -JTE and hidden-PJTE, respectively.
  • 1.0K
  • 26 Oct 2021
Topic Review
Synthesis of Metabolite of Resveratrol by Beauveria bassiana
Resveratrol is a well-known dietary polyphenol because it has a variety of beneficial biological activities. The fungus Beauveria bassiana is one of the most frequently used microorganisms for the biotransformation of polyphenols. Recently, resvebassianol A (2), a glycosylated metabolite of resveratrol by B. bassiana, was isolated and structurally elucidated. It was demonstrated to exhibit antioxidant, regenerative, and anti-inflammatory activities with no cytotoxicity. Here, we report the first total synthesis of resvebassianol A, 4'-O-β-(4'"-O-methylglucopyranosyl)resveratrol (2), and its regiomer, 3-O-β-(4 -O-methylglucopyranosyl)resveratrol (3). Key reactions include (i) the construction of a stilbene core via a novel Heck reaction of aryl halides and styrenes, and (ii) glycosylation with unnatural methylglucopyranosyl bromide. The glycosylation step was carefully optimized by varying the bases and solvents. Resveratrol metabolites 2 and 3 were obtained at 7.5% and 6.3% of the overall yield, respectively.
  • 677
  • 25 Oct 2021
Topic Review
Red Alga Dixoniella grisea
There is an increasing interest in algae-based raw materials for medical, cosmetic or nutraceutical applications. Additionally, the high diversity of physicochemical properties of the different algal metabolites proposes these substances from microalgae as possible additives in the chemical industry. Among the wide range of natural products from red microalgae, research has mainly focused on extracellular polymers for additive use, while this study also considers the cellular components. 
  • 586
  • 25 Oct 2021
Topic Review
Keratin-Based Nanoparticles as Drug Delivery Carriers
Keratin is a structural protein of mammalian tissues and birds, representing the principal constituent of hair, nails, skin, wool, hooves, horns, beaks, and feathers, and playing an essential role in protecting the body from external harassment. Due to its intrinsic features such as biocompatibility, biodegradability, responsiveness to specific biological environment, and physical-chemical properties, keratin has been extensively explored in the production of nanocarriers of active principles for different biomedical applications.
  • 696
  • 25 Oct 2021
Topic Review
Tube High-Pressure Shearing
Tube high-pressure shearing (t-HPS) is a deformation processing, in which a tubular sample is subjected to azimuthal shearing under a hydrostatic pressure. The shear plane is in parallel to the cylindrical surface of the tube, and the shear direction is in the azimuthal direction. 
  • 539
  • 25 Oct 2021
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