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Topic Review
Metal Phosphates and Pyrophosphates as Proton Conductors
It is about the progress in metal phosphate structural chemistry focused on proton conductivity properties. Attention is paid to structure–property relationships, which ultimately determine the potential use of metal phosphates and derivatives in devices relying on proton conduction. The origin of their conducting properties, including both intrinsic and extrinsic conductivity, is rationalized in terms of distinctive structural features and the presence of specific proton carriers or the factors involved in the formation of extended hydrogen-bond networks.
  • 750
  • 19 Apr 2022
Topic Review
Application of Ionic Liquids for Metals
The recovery and separation of individual elements, critical materials and valuable metals from complex systems requires complex energy-consuming solutions with many hazardous chemicals used. Ionic liquids (ILs), also known as molten salts and future solvents, are endowed with unique features that have already had a promising impact on cutting-edge science and technologies. Functionalized ILs, solid extraction, Supported Ionic Liquid Phase (SILP), and agricultural waste-based IL show great promise for sustainable high-value metal recovery. 
  • 750
  • 10 Feb 2022
Topic Review
Liquid Chromatography Separation Mechanism
Separation is a critical process to isolate a particular compound, whether it is a natural product or a synthetic product. Studies of a compound’s characteristics and elucidation structure provides reliable results for pure compounds because there is no interference from other compounds. The primary source of difficulty in a separation process is the high similarity between two or more compounds, such as racemic and homologous mixtures. Liquid chromatography has proven to be an effective solution to those problems. The key to liquid chromatography separation is a sustainable retention and elution process. Stationary phases are essential for separating compounds in liquid chromatography. Various liquid chromatography columns of both preparative and quantitative types have been used and continue to develop. This research will discuss the separation mechanism in liquid chromatography.
  • 742
  • 02 Mar 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. 
  • 741
  • 09 Sep 2022
Topic Review
Chitosan Nanostructures
Chitosan (CS) is a natural polymer with a positive charge, a deacetylated derivative of chitin. Chitosan nanostructures (nano-CS) have received increasing interest due to their potential applications and remarkable properties. 
  • 739
  • 04 Nov 2021
Topic Review
List of Adrenergic Drugs
This is a list of adrenergic drugs. These are pharmaceutical drugs, naturally occurring compounds and other chemicals that influence the function of the neurotransmitter epinephrine (adrenaline).
  • 733
  • 21 Oct 2022
Topic Review
Ru(II)-Dppz Derivatives and DNA
Transition metal complexes with dppz-type ligands (dppz = dipyrido[3,2-a:2′,3′-c]phenazine) are extensively studied and attract a considerable amount of attention, becoming, from the very beginning and increasingly over time, a powerful tool for investigating the structure of the DNA helix. In particular, [Ru(bpy)2(dppz)]2+ and [Ru(phen)2(dppz)]2+ and their derivatives were extensively investigated as DNA light-switches. 
  • 730
  • 13 Apr 2021
Topic Review
Catalysts for Glycerol Reforming
The valuable products produced from glycerol transformation have become a research route that attracted considerable benefits owing to their huge volumes as well as a myriad of chemical and biological techniques for transforming glycerol into high-value compounds, such as fuel additives, biofuels, precursors, and other useful chemicals, etc. Steam, aqueous, and autothermal reforming processes have been primarily investigated in glycerol reforming. An update on glycerol reforming is given, with an exclusive focus on the various catalyst's performance in designing reaction operation conditions.
  • 725
  • 25 Jul 2022
Topic Review Peer Reviewed
The Production of Isophorone
Isophorone is a technically important compound used as a high-boiling-point solvent for coatings, adhesives, etc., and it is used as a starting material for various valuable compounds, including isophorone diisocyanate, a precursor for polyurethanes. For over 80 years, isophorone has been synthesized via base-catalyzed self-condensation of acetone. This reaction has a complex reaction mechanism with numerous possible reaction steps including the formation of isophorone, triacetone dialcohol, and ketonic resins. This review provides an overview of the different production processes of isophorone in liquid- and vapor-phase and reviews the literature-reported selectivity toward isophorone achieved using different reaction parameters and catalysts.
  • 725
  • 29 Mar 2023
Topic Review
Metal Halide Perovskites as Photocatalysts
The possible use of MHPs as effective photocatalysts has become clear to the scientific community in the last few years. Bulk and nanocrystalline metal halide perovskites have been shown to be excellent semiconductors with suitable energy levels to run most of the key solar-driven reactions of current interest for solar fuels production. This review summarized the current status of the application of MHPs in photocatalyzed organic syntheses/transformation which to date have shown, in most of the cases, significant advantages with respect to traditional photocatalysts.
  • 724
  • 02 Aug 2021
Topic Review
Impact of Wort Amino Acids on Beer Flavour
The process by which beer is brewed has not changed significantly since its discovery thousands of years ago. Grain is malted, dried, crushed and mixed with hot water to produce wort. Yeast is added to the sweet, viscous wort, after which fermentation occurs. The biochemical events that occur during fermentation reflect the genotype of the yeast strain used, and its phenotypic expression is influenced by the composition of the wort and the conditions established in the fermenting vessel. Although wort is complex and not completely characterized, its content in amino acids indubitably affects the production of some minor metabolic products of fermentation which contribute to the flavour of beer. 
  • 722
  • 29 May 2023
Topic Review
Bioethanol production by enzymatic hydrolysis
Lignocellulosic sources are the world’s largest renewable sources for bioethanol production and can be divided into three main types: (1) marine algae, (2) agricultural residues and municipal solid wastes, (3) and forest woody feedstocks.
  • 719
  • 19 Jul 2021
Topic Review
Catalyst-Support Interactions Promoted Acidic Electrochemical Oxygen Evolution Catalysis
In the context of the growing human demand for green secondary energy sources, proton-exchange membrane water electrolysis (PEMWE) is necessary to meet the high-efficiency production of high-purity hydrogen required for proton-exchange membrane fuel cells (PEMFCs). The development of stable, efficient, and low-cost oxygen evolution reaction (OER) catalysts is key to promoting the large-scale application of hydrogen production by PEMWE. 
  • 715
  • 03 Apr 2023
Topic Review
Photonic Crystals-based Plasmonic Photocatalysts
Plasmonic photocatalysts, noble-metal (NM)-modified wide-bandgap semiconductors with activity under visible-light (vis) irradiation, due to localized surface plasmon resonance (LSPR), have been intensively investigated over the last few years as efficient materials for environmental purification and energy conversion. However, the low quantum yields of photocatalytic reactions under vis irradiation, resulting from fast charge carriers' recombination, must be overcome for possible commercialization. Accordingly, the morphology design of plasmonic photocatalysts for efficient light harvesting has been proposed by using wide-bandgap semiconductors in the form of photonic crystals (PCs). 
  • 712
  • 02 Nov 2020
Topic Review
Bulk Preparation Technologies in Food Packaging Applications
Active packaging has played a significant role in consumers’ health and green environment. Synthetic polymers, such as poly(ethylene terephthalate) (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), poly(vinyl chloride) (PVC), polycarbonate (PC), poly(lactic acid) (PLA), etc., and naturally derived ones, such as cellulose, starch, chitosan, etc., are extensively used as packaging materials due to their broad range of desired properties (transparence, processability, gas barrier properties, mechanical strength, etc.). The food packaging field has been challenged to deliver food products free from microbes that cause health hazards. However, most of the used polymers lack such properties. Owing to this, active agents such as antimicrobial agents and antioxidants have been broadly used as potential additives in food packaging substrates, to increase the shelf life, the quality and the safety of food products. Both synthetic active agents, such as Ag, Cu, ZnO, TiO2, nanoclays, and natural active agents, such as essential oils, catechin, curcumin, tannin, gallic acid, etc., exhibit a broad spectrum of antimicrobial and antioxidant effects, while restricting the growth of harmful microbes. Various bulk processing techniques have been developed to produce appropriate food packaging products and to add active agents on polymer matrices or on their surface. Among these techniques, extrusion molding is the most used method for mass production of food packaging with incorporated active agents into polymer substrates, while injection molding, thermoforming, blow molding, electrospinning, etc., are used to a lower extent.
  • 700
  • 27 Dec 2022
Topic Review
Molecular Iodine Capture by Covalent Organic Frameworks
Covalent organic frameworks (COFs) are a class of extended crystalline porous polymers that possess unique architectures with high surface areas, long-range order, and permanent porosity. It is known that the possible radioactive iodine species in the environment are iodate (IO3−), molecular iodine (I2), and organic iodine species (e.g., methyl iodide (CH3I) and ethyl iodide (CH3CH2I)). Different iodine species need to be handled in different ways.
  • 699
  • 14 Feb 2023
Topic Review
Nanofilms
Nanofilms are thin films that are composed of nanoscale materials and have thicknesses typically ranging from a few nanometers to a few hundred nanometers. Nanofilms have unique properties that make them useful in a wide range of applications, including electronics, biomedicine, manufacturing, food, surface protection, and environmental protection. Nanofilms can be made from a variety of materials, including metals, ceramics, polymers, and composites. They can be designed with specific properties, such as high surface area, improved mechanical and chemical stability, and tailored optical and electrical properties. These unique properties of nanofilms make them useful in a wide range of applications.
  • 699
  • 06 Feb 2023
Topic Review
Treatment Methods for Dye-Contaminated Effluents
Advancements in textile dyeing technologies have introduced novel categories of dyes that have deleterious effects on ecosystems. Primarily, azo dyes represent the majority of synthetic dyes employed in textiles and in the realms of culinary and miscellaneous applications. Traditionally, these dyes infiltrate the environment via discharged contaminated effluents such as wastewater from industrial facilities. The contaminated discharged effluent exerts a pervasive impact on ecosystems, engendering pernicious afflictions in both human and faunal populations. Several treatment methodologies are employed for the eradication of contaminants from natural water resources and wastewater, encompassing all phases within water and wastewater treatment infrastructures. The evolution of each treatment stage is intricately linked to the escalating demand for potable water of impeccable quality. Water treatment methods such as Coagulation and Flocculation, Photocatalytic Degradation, Ion Exchange, Electrochemical Technique, Membrane Filtration, Electrodialysis Process, Biodegradation Techniques, and Adsorption are covered in detail, alongside the impacts of bio-based activated carbon as an adsorbent for azo dye. 
  • 691
  • 26 Sep 2023
Topic Review
Fabrication of SiC Membranes
The scale of research for developing and applying silicon carbide (SiC) membranes for gas separation has rapidly expanded over the last few decades. The precursor-derived ceramic approaches for preparing SiC membranes include chemical vapor deposition (CVD)/chemical vapor infiltration (CVI) deposition and pyrolysis of polymeric precursor. Generally, SiC membranes formed using the CVD/CVI deposition route have dense structures, making such membranes suitable for small-molecule gas separation. On the contrary, pyrolysis of a polymeric precursor is the most common and promising route for preparing SiC membranes, which includes the steps of precursor selection, coating/shaping, curing for cross-linking, and pyrolysis. Among these steps, the precursor, curing method, and pyrolysis temperature significantly impact the final microstructures and separation performance of membranes.
  • 690
  • 19 Feb 2023
Topic Review
Nanocomposites: Brief Overview
Nanocomposites are composite materials consisting of nanoscale building blocks and a matrix. Nanocomposites are materials composed of a polymer matrix reinforced with nanoparticles, typically with dimensions ranging from 1 to 100 nanometers. These nanoparticles can be made of various materials, such as metals, ceramics, and carbon-based materials, and they can be dispersed uniformly throughout the polymer matrix They have unique properties that make them useful in a wide range of applications, including water remediation, energy storage and conversion, packaging, sensors, biomedicine, environmental monitoring, and coatings. The properties of nanocomposites can be tailored by controlling the size, shape, and composition of the nanoscale building blocks and the matrix material. Some of the key properties of nanocomposites include high surface area-to-volume ratio, improved mechanical properties, enhanced electrical and thermal conductivity, improved barrier properties, and biocompatibility. The study of nanocomposites is a rapidly growing field with many exciting opportunities for new and improved applications.These articles provide a comprehensive overview of the synthesis, structure, properties, and applications of nanocomposites, including their use in water remediation.
  • 689
  • 23 Mar 2023
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