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Topic Review
Recent Advances of Deep Eutectic Solvents
Deep Eutectic Solvents (DESs) have gained a lot of attention in the last few years because of their vast applicability in a large number of technological processes, the simplicity of their preparation and their high biocompatibility and harmlessness.
  • 1.3K
  • 07 Apr 2022
Topic Review
Natural Clinoptilolite
Zeolites are ionic conductors and the cation electrical mobility in zeolites depends on their hydration state; consequently, the water adsorption/desorption process can be simply investigated by measuring the temporal evolution of current intensity in samples exposed to an environment with constant humidity or dry air, respectively. According to this kinetic analysis, a mechanism has been formulated for the water adsorption process able to justify the Lagergren pseudo-first-order kinetics observed for adsorption and the first-order kinetics observed for desorption. In this mechanism water molecules are first attract by the electric field of the cations and then they move at cation-framework interface to maximize the hydrogen bond interactions.
  • 1.3K
  • 28 Oct 2020
Topic Review
Synthesis Procedures of Porphyrin-Based Metal–Organic Frameworks
Metal–organic frameworks (MOFs)—typically formed from metal ions/clusters bridged by multidentate ligands in an extended framework—have provided solutions to tackle challenges in areas such as catalysis. By either integrating porphyrins/metalloporphyrins inside pores freely in situ or by grafting on the surface using post-synthetic methods and/or as part of the network component, porphyrin-based MOFs could be easily constructed.
  • 1.2K
  • 24 Aug 2022
Topic Review
Chemical and Physical Properties of Solid Salt Fluxes
Solid salt fluxes are inorganic compounds that are added during the treatment of molten aluminum to improve the final quality. An understanding of the chemical composition of the flux is essential for the assessment of the physical and chemical behavior of the flux. The chemical composition of the flux can be tailored to adjust properties such as density, viscosity, reactivity, and wettability. Such properties, in turn, will impart different functions to the flux. 
  • 1.2K
  • 05 May 2023
Topic Review
Glyphosate
Glyphosate [N-(phosphonomethyl) glycine CAS#1071-83-6] is one of the most extensively used broad-spectrum organophosphorus herbicides [1]. It is a widely used herbicide in agriculture against perennial and annual weeds and in silviculture, domestic gardens, and urban areas [2]. 
  • 1.2K
  • 26 Oct 2020
Topic Review
Methods to Synthesize Ultrasmall AuNPs
Gold nanoparticles (AuNPs) are continuing to gain popularity in the field of nanotechnology. New methods are continuously being developed to tune the particles’ physicochemical properties, resulting in control over their biological fate and applicability to in vivo diagnostics and therapy. The common methods of synthesizing ultrasmall AuNPs are presented.
  • 1.2K
  • 09 Aug 2022
Topic Review
Ti-Based Catalysts on Magnesium Hydride
Magnesium-based hydrides are considered as promising candidates for solid-state hydrogen storage and thermal energy storage, due to their high hydrogen capacity, reversibility, and elemental abundance of Mg. To improve the sluggish kinetics of MgH2, catalytic doping using Ti-based catalysts is regarded as an effective approach to enhance Mg-based materials.
  • 1.2K
  • 31 May 2021
Topic Review
Cement-Based Repair Materials with Concrete Substrates
Cement concrete is currently the most widely used civil engineering construction material worldwide and has been applied in various civil infrastructures, such as roads, bridges, ports and tunnels. Under the external loads and environmental impacts, concrete structures are prone to be damaged, such as cracking and even spalling. In addition, inappropriate selection of raw materials, incorrect mixture design and irregular construction process may also cause damages to concrete, particularly regarding the cover protecting the reinforcement bars.
  • 1.1K
  • 13 Apr 2022
Topic Review
Boron Chemicals
Boron-based bioactive compounds have provided amphiphilic properties to facilitate interaction with protein targets. Indeed, the spectrum of boron-based entities as drug candidates against many diseases has grown tremendously since the first clinically tested boron-based drug, Velcade. 
  • 1.0K
  • 27 Apr 2022
Topic Review
Van der Waals Heterostructures
van der Waals heterostructures are stacks of 2D sheets. The basal planes of each sheet are held strongly together by covalent bonding, while van der Waals forces keep them fixed in a sort of sandwich structure. It is not an underestimation that vdW structures can be projected as atomic-scale Lego blocks.
  • 964
  • 26 Jul 2021
Topic Review Peer Reviewed
Nuclear Waste Disposal
Nuclear waste (like radioactive waste) is waste that contains, or is contaminated with, radionuclides, at activity concentrations greater than clearance levels set by the regulators, beyond which no further use is foreseen. Disposal is the emplacement of waste in an appropriate facility without the intention to retrieve it.
  • 940
  • 03 Apr 2023
Topic Review
Zn(II) AIEgens: “Clip Approach”
 Aggregation-induced emission (AIE) compounds display a photophysical phenomenon inwhich the aggregate state exhibits stronger emission than the isolated units. The common term of“AIEgens” was coined to describe compounds undergoing the AIE effect. Due to the recent interestin AIEgens, the search for novel hybrid organic–inorganic compounds with unique luminescenceproperties in the aggregate phase is a relevant goal. In this perspective, the abundant, inexpensive,and nontoxic d10 zinc cation offers unique opportunities for building AIE active fluorophores, sensingprobes, and bioimaging tools. Considering the novelty of the topic, relevant examples collected inthe last 5 years (2016–2021) through scientific production can be considered fully representative ofthe state-of-the-art. Starting from the simple phenomenological approach and considering differenttypological and chemical units and structures, we focused on zinc-based AIEgens offering syntheticnovelty, research completeness, and relevant applications. A special section was devoted to Zn(II)-based AIEgens for living cell imaging as the novel technological frontier in biology and medicine.
  • 932
  • 22 Jul 2021
Topic Review
Self-sterilizing Properties of Copper
It is confirmed that copper is a self-sanitising metal, acting on human pathogens in a way that does not let them survive exposure to copper or copper alloy surfaces for any reasonable length of time. Regarding the efficacy of copper surfaces, testing in an independent microbiology laboratory has led to 300 various copper surfaces being registered with the United States Environmental Protection Agency (USEPA) in 2008. The registration includes the following statement: “When cleaned regularly, the antimicrobial copper alloy surface kills greater than 99.9% of bacteria within two hours and continues to kill more than 99% of bacteria even after repeated contamination”. This claim acknowledges that copper and its alloys brass and bronze can kill potentially deadly bacteria, and sometime later, it was further understood that copper nanoparticles (Cu-NPs) and laser textured copper also show enhanced antimicrobial activity.
  • 915
  • 06 Jul 2021
Topic Review
AAZTA-Derived Chelators as Innovative Radiopharmaceuticals
The chelating agent AAZTA features a mesocyclic seven-membered diazepane ring, conferring some of the properties of both acyclic and macrocyclic chelating agents. Described in the early 2000s, AAZTA and its derivatives exhibited interesting properties once complexed with metals and radiometals, combining a fast kinetic of formation with a slow kinetic of dissociation. Importantly, the extremely short coordination reaction times allowed by AAZTA derivatives were particularly suitable for short half-life radioelements (i.e., 68Ga).
  • 908
  • 28 Feb 2022
Topic Review
Synthesis of Ferrocenyl Phosphorhydrazone Dendrimers
The discovery of ferrocene is often associated with the rapid growth of organometallic chemistry. Dendrimers are highly branched macromolecules that can be functionalized at will at all levels of their structure. The functionalization of dendrimers with ferrocene derivatives can be carried out easily as terminal functions on the surface, but also at the core, or at one or several layers inside the structure. Depending on the desired location of the ferrocenes in the structure of phosphorhydrazone dendrimers, the ferrocenes should be functionalized differently. For the grafting to the surface, the ferrocene should bear a phenol group, suitable to react in substitution reactions with the P(S)Cl2 terminal groups of the dendrimers. To be used as core, the ferrocene should have two aldehyde functions, from which the synthesis of the dendrimer will be carried out. To be introduced in the branches, at all layers or within a single layer, the ferrocene should replace hydroxybenzaldehyde; thus, it should bear both a phenol and an aldehyde.
  • 906
  • 06 Jun 2022
Topic Review
Crystalline Peroxosolvates
Peroxosolvates - adducts of hydrogen peroxide and molecules or salts formed by hydrogen bonding.
  • 899
  • 19 Jan 2021
Topic Review
Cluster-Based Coordination Polymers
Cluster-based coordination polymers (CCPs) are constructed from metal coordination clusters that are bridged by polytopic organic ligands forming multidimensional systems such as one-dimensional (1D) chains, two-dimensional (2D) layers, and three-dimensional (3D) metal-organic frameworks. Structurally well-defined polynuclear Mn(II,III)/Fe(III)-oxo pivalate and isobutyrate clusters recommend them-selves as extremely versatille building blocks where their ancillary coordination ligands are sufficiently flexible to allow the formation of a wide variety of 1D, 2D and 3D CCPs.
  • 895
  • 07 May 2021
Topic Review
Luminescent Ln-Ionic Liquids beyond Europium
What is called an ionic liquid (IL) has a very broad definition, comprising multiple substances possessing a wide diversity of structures and properties. An IL consists of both organic and inorganic ions, and may contain more than one cation or anion. Normally, a substance is considered to be an IL if completely composed of ions, with a melting point below 100 °C. Ionic liquids containing lanthanides or lanthanide compounds in ionic liquids are very important in the field of soft luminescent materials. 
  • 889
  • 27 Aug 2021
Topic Review
Cadmium Recovery from Spent Ni-Cd Batteries
The significant increase in the demand for efficient electric energy storage during the last decade has promoted an increase in the production and use of Cd-containing batteries. On the one hand, the amount of toxic Cd-containing used batteries is growing, while on the other hand, Cd is on a list of critical raw materials (for Europe). Both of these factors call for the development of effective technology for Cd recovery from spent batteries. Alkaline nickel-cadmium (Ni-Cd) batteries are widely used as autonomous sources of industrial and household current (power banks) due to a successful combination of feasibility studies and achieved sustainable electrical characteristics. In recent decades, the market of secondary current sources for portable equipment has undergone significant changes, which leads to an intensive replacement of Ni-Cd batteries with lithium-ion (LIB) and nickel-metal-hydride.
  • 847
  • 07 Feb 2022
Topic Review
Asymmetric Recognition by Chiral Porphyrinoids
Over the years, chiral discrimination of chiral molecules such as amino acids, alcohols, amines, hydroxy-carboxylic acids, etc. has aroused the interest of the scientific community. Thus, numerous studies have reported the possibility to discriminate several organic guests by using both symmetric and asymmetric porphyrin derivatives. Nevertheless, this entry exclusively focuses on chiral porphyrinoids as probes for asymmetric recognition and sensing, illustrating the main aspects concerning the chiral recognition phenomena of a multitude of chiral organic guests through several chiral mono- and bis-porphyrins via different spectroscopic techniques.
  • 843
  • 17 Nov 2021
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