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Topic Review
Humic Substances
Humic substances are a very important part of our soil.  The topic is description of the structure of humic substances using NMR.  The NMR part is divided into two parts, liquid and solid state NMR.  The assignment of NMR spectra are discussed and the structural elements that can be deduced from the spectral information.  Principal Component Analysis is used as a tool to categorize the information.  Structural models are discussed.
  • 2.8K
  • 16 Jul 2024
Topic Review
DFT Calculations of XH Stretching Frequencies
X in the title can be either O or N.  Hydrogen bond potentials can be either symmetric or unsymmetric.  The former is the case for CH bonds, whereas for hydrogen bonded systems the potential can be more or less asymmetric depending on the strength of the hydrogen bond. DFT is an abbrviation for Density Functional Theory; CPMD = Car-Parinello Molecular Dynamics and VPT2  = Vibrational Second Order Pertubation Theory.  RAHB = Resonace Assisted Hydrogen Bonding.
  • 799
  • 13 Jul 2024
Topic Review
NTC-Properties of a Geomorphic Clinoptilolite Sample
Negative temperature coefficient (NTC) materials are usually based on ceramic semiconductors, and electrons are involved in their transport mechanism. A new type of NTC material, adequate for alternating current (AC) applications, is represented by zeolites. Indeed, zeolites are single charge carrier ionic conductors with a temperature-dependent electrical conductivity. In particular, electrical transport in zeolites is due to the monovalent charge-balancing cations, like K+, capable of hopping between negatively charged sites in the aluminosilicate framework. Owing to the highly non-linear electrical behavior of the traditional electronic NTC materials, the possibility to have alternative types of materials, showing linearity in their electrical behavior, is very desirable. Among different zeolites, natural clinoptilolite has been selected for investigating NTC behavior since it is characterized by high zeolite content, a convenient Si/Al atomic ratio, good mechanical strength due to its compact microstructure, and low toxicity. Clinoptilolite has shown a rapid and quite reversible impedance change under heating, characterized by a linear dependence on temperature.
  • 1.1K
  • 11 Jul 2024
Topic Review
Synergistic Effect of Nanoparticles
The synergistic impact of nanomaterials is critical for novel intracellular and/or subcellular drug delivery systems of minimal toxicity. This synergism results in a fundamental bio/nano interface interaction, which is discussed in terms of nanoparticle translocation, outer wrapping, embedding, and interior cellular attachment. The morphology, size, surface area, ligand chemistry and charge of nanoparticles all play a role in translocation.
  • 89
  • 14 Jun 2024
Topic Review
CO2 Hydroboration
The use of CO2 as C1 building block for chemical synthesis is receiving growing attention, due to the potential of this simple molecule as abundant and cheap renewable feedstock. Among the possible reductants used in the literature to bring about CO2 reduction to C1 derivatives, hydroboranes have found various applications, in the presence of suitable homogenous catalysts. The main results obtained since 2016 in the synthetic design of main group, first and second row transition metals for use as catalysts for CO2 hydroboration are summarized.
  • 1.6K
  • 04 Jun 2024
Topic Review
Magnetic Material Nanoparticles
Magnetic material nanoparticles (MNPs) have been widely used in the detection and treatment of bacterial infections as detection agents and therapeutics. Infections caused by pathogenic bacteria, especially multidrug-resistant bacteria, have become a serious worldwide public health problem. Early diagnosis and treatment can effectively prevent the adverse effects of such infections. Therefore, there is an urgent need to develop effective methods for the early detection, prevention, and treatment of diseases that are caused by bacterial infections.
  • 857
  • 23 May 2024
Topic Review
Nanoparticle Constructions to Target Staphylococcus aureus Pathogenesis
The clinical infections by Staphylococcus aureus caused an increase in morbidity and mortality rates and treatment costs, aggravated by the emergence of drug-resistant strains. Different nanotechnology-enabled approaches are being investigated that can improve the paradigm of therapeutics against S. aureus pathogenesis and infections. Nanomaterials provide a suitable platform to address this challenge, with the potential to control biofilm formation, intracellular parasitism and multidrug resistance where conventional therapies show limited efficacy. Herein, the large diversity of nanoparticles and their applications to combat S. aureus pathogenesis, including in combination with antibiotics and phytochemicals, is presented and their specific biological actions are highlighted.
  • 429
  • 22 May 2024
Topic Review
Materials Science, Glasses
Glasses are solid amorphous materials which transform into liquids upon heating through the glass transition. The International Commission on Glass defines glass as a state of matter, usually produced when a viscous molten material is cooled rapidly to below its glass transition temperature, with insufficient time for a regular crystal lattice to form. The solid-like behaviour of glasses is separated from the liquid-like behaviour at higher temperatures by the glass transition temperature, Tg. The IUPAC Compendium on Chemical Terminology defines glass transition as a second order transition in which a supercooled melt yields, on cooling, a glassy structure. It states that below the glass-transition temperature the physical properties of glasses vary in a manner similar to those of the crystalline phase. Moreover, it is deemed that the bonding structure of glasses has the same symmetry signature in terms of Hausdorff-Besikovitch dimensionality of chemical bonds as for the crystalline materials. 
  • 3.3K
  • 09 May 2024
Topic Review
Hydrometallurgy and Germanium Recovery from Secondary Resources
Though nowadays germanium do not reach the range of popularity than other metals, i.e. rare earth elements, its utility in target industries makes of it also a strategic metal. Though germanium can be found in a series of raw materials, the principal source for its recovery is from secondary wastes of the zinc industry, also, the recycle of germanium-bearing waste materials is becoming of interest. In this recovery the size of the target materials because the diffusion and reaction are to be considered, Hydrometallurgy is performing a key role to the successful achievement of this goal. The present work reviews the most recent applications (2023 and 2024 years) of hydrometallurgical operations on the recovery of germanium from different solid and liquid sources.  
  • 286
  • 30 Apr 2024
Topic Review
Physical Hydrogen Storage Materials
Hydrogen is a future energy carrier in the global energy system and has the potential to produce zero carbon emissions. For the non-fossil energy sources, hydrogen and electricity are considered the dominant energy carriers for providing end-user services, because they can satisfy most of the consumer requirements. Hence, the development of both hydrogen production and storage is necessary to meet the standards of a “hydrogen economy”. The physical and chemical absorption of hydrogen in solid storage materials is a promising hydrogen storage method because of the high storage and transportation performance.
  • 253
  • 18 Apr 2024
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