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Topic Review
Ni-Based Bimetallic Catalysts
Metallic Ni shows high activity for a variety of hydrogenation reactions due to its intrinsically high capability for H2 activation, but it suffers from low chemoselectivity for target products when two or more reactive functional groups are present on one molecule. Modification by other metals changes the geometric and electronic structures of the monometallic Ni catalyst, providing an opportunity to design Ni-based bimetallic catalysts with improved activity, chemoselectivity, and durability.
  • 709
  • 07 Feb 2022
Topic Review
Ni Single-Atom Catalysts
Nickel is a well-known catalyst in hydrogenation and dehydrogenation reactions. It is currently used in industrial processes as a homogenous and heterogeneous catalyst. However, to reduce the cost and increase the efficiency of catalytic processes, the development of single-atom catalysts (SACs) seems promising. Some SACs have already shown increased activity and stability as compared to nanoparticle catalysts.
  • 407
  • 15 May 2023
Topic Review
NGF Peptides Bind Copper(II)
Nerve growth factor (NGF) is a protein essential to neurons survival, which interacts with its receptor as a non-covalent dimer. Copper affects biological activity of NGF and conversely NGF may regulates copper trafficking in synaptic cleft.
  • 556
  • 10 Jun 2021
Topic Review
NFPCs under Different Strain Rates
With the lightning speed of technological evolution, the demand for high performance yet sustainable natural fibres reinforced polymer composites (NFPCs) are rising. Especially a mechanically competent NFPCs under various loading conditions are growing day by day. NFPCs mechanical properties highly depend on strain rate due to their viscoelastic and viscoplastic behaviour. Pure viscoelastic behaviour usually occurs within a small amount of strain. While the viscoplastic inelastic strain only accumulates when it reaches a certain amount depending on the material. NFPCs under a different type of strain rates could also exhibit diverse mechanical properties and failure mechanism.
  • 597
  • 01 Jun 2021
Topic Review
NF Mercerization/Alkali Surface Treatment
The benefits of using natural fibres (NFs) such as Coir, flax, hemp, and bast fibres as a reinforcement in polymer composites than synthetic fibres, are low cost, lower density, more recyclable and have greater “biodegradability”. Alkali treatment is used to breaking down the bundles of fibres into individual fibres. This process results in an increased aspect ratio of the smaller fibre particles and makes the fibre surface rough, which helps in increasing the interfacial bonding between fibre and the matrix material. Alkali treatment is an effective surface treatment method, helpful in removing some amount of lignin, impurities, which covers the fibre surface, depolymerize the cellulose structures. The main problem in the development of the NF composite is their less adhesion ability with the matrix. Mercerization is one of the best ways to improve fibre-matrix adhesion. Because of the hydrophilic nature of the fibre, Chemical treatment is found to be one of the great solutions that make the fibre surface rough and removes fatty deposits from the fibre called “xyloses”. Alkali treatment results in the rough fibre surface and enhances the fibre surface area, leading to the excellent interlocking with the matrix.
  • 532
  • 15 Jul 2021
Topic Review
Next-Generation Gingival Graft Substitutes
There is a shortage of suitable tissue-engineered solutions for gingival recession, a soft tissue defect of the oral cavity. Autologous tissue grafts lead to an increase in morbidity due to complications at the donor site. Although material substitutes are available on the market, their development is early, and work to produce more functional material substitutes is underway. The latter materials along with newly conceived tissue-engineered substitutes must maintain volumetric form over time and have advantageous mechanical and biological characteristics facilitating the regeneration of functional gingival tissue.
  • 833
  • 17 May 2022
Topic Review
New Modification of PbF(IO3)
New crystals of PbF(IO3) polytype modification are synthesized hydrothermally and demonstrate strong SHG optical response. They are phase-matchable at the fundamental wavelength of 1064 nm. The crystal structure was solved in two space groups, orthorhombic C2ma and monoclinic Pn, of which monoclinic is true and is described with a twinning by mirror plane introduced in structural refinements taken into account. Orthorhombic symmetry was used in comparison with the related structures and deviation close similarity in the selected suggested family MX(IO3), M = Bi, Ba­, Pb, X= O, F, (OH) with series of members. These compounds were also characterizing as similar to Aurivillius phases with fluorite-like layer and perovskite-like layer substituted by (IO3) groups. The optical nonlinearity of the iodates of the Aurivillius family and structurally related iodates is determined by the polar orientation of the iodate groups, which make an overwhelming contribution to the optical nonlinearity. From crystal chemistry point of view, the heavy atoms in these structures are located in the second cation environments in relation to the iodate groups and indirectly affect the nonlinearity. In particular, large Ba-cations without single electron pairs provoke a symmetric variant of the Aurivillius type structure, in contrast to the acentric Bi3+ and Pb2+ cations known in polar iodates with strong second-order optical nonlinearity. There is wide diversity in the extended series of related compounds which includes variation of fluorite-like layers (single or double), perovskite-like layers presented by octahedral or more complicate polyhedral, or by IO3 (BrO3) groups, or by Cl-atoms, or by NH4-groups. This allows the development of future search for new promising phases.
  • 444
  • 01 Feb 2023
Topic Review
New Marine Xanthones Isolated since 2010
Xanthones are considered polyketide derivatives due to their biosynthetic precursor. They are aromatic oxygenated heterocyclic compounds with a dibenzo-γ-pyrone scaffold, known as 9H-xanthen-9-one.
  • 473
  • 27 Jun 2022
Topic Review
New Liquid Chemical Hydrogen Storage Technology
The liquid chemical hydrogen storage technology has great potentials for high-density hydrogen storage and transportation at ambient temperature and pressure. However, its commercial applications highly rely on the high-performance heterogeneous dehydrogenation catalysts, owing to the dehydrogenation difficulty of chemical hydrogen storage materials. The chemists and materials scientists found that the supported metal nanoparticles (MNPs) can exhibit high catalytic activity, selectivity, and stability for the dehydrogenation of chemical hydrogen storage materials, which will clear the way for the commercial application of liquid chemical hydrogen storage technology. 
  • 677
  • 09 Sep 2022
Topic Review
New Horizons in Structural Biology of Membrane Proteins
A third of both pro- and eukaryotic proteomes consist of membrane proteins. Housed in a milieu of hydrophobic molecules, they serve as crucial contacts of communication between the cytoplasm and non-cytosolic environments, making them essential pharmaceutical targets. While membrane proteins are notoriously difficult to investigate at any level, high-resolution structures of these targets only became feasible at the very end of the twentieth century. It was not until robust technological developments in the fields of X-ray crystallography, NMR spectroscopy and cryo-EM, that the scientific community at large, finally gained access to an ever-increasing number of atomic resolution structures, and began to rationalize how membrane proteins accommodate their function. As if the lack of structural information wasn’t enough to hamper progress, a higher level of complexity arose from the modern understanding of “one structure—one function” paradigm, a primitive simplification useful at the dawn of the scientific era, that has promptly lost credence to the complex maneuvers of membrane proteins.
  • 533
  • 26 Apr 2022
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