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Topic Review
Compounds of Thorium
Many compounds of thorium are known, this is because thorium and uranium are the most stable and accessible actinides and are the only actinides that can be studied safely and legally in bulk in a normal laboratory. As such, they have the best-known chemistry of the actinides, along with that of plutonium, as the self-heating and radiation from them is not enough to cause radiolysis of chemical bonds as it is for the other actinides. While the later actinides from americium onwards are predominantly trivalent and behave more similarly to the corresponding lanthanides, as one would expect from periodic trends, the early actinides up to plutonium (thus including thorium and uranium) have relativistically destabilised and hence delocalised 5f and 6d electrons that participate in chemistry in a similar way to the early transition metals of group 3 through 8: thus, all their valence electrons can participate in chemical reactions, although this is not common for neptunium and plutonium.
  • 2.4K
  • 25 Oct 2022
Topic Review
Copper-Based Metal–Organic Frameworks for Click Chemistry
In the extensive terrain of catalytic procedures for the synthesis of organic molecules, metal–organic frameworks (MOFs) as heterogenous catalysts have been investigated in a variety of chemical processes, including Friedel–Crafts reactions, condensation reactions, oxidations, and coupling reactions, and utilized owing to their specific properties such as high porosity, tuneability, extraordinary catalytic activity, and recyclability.
  • 2.3K
  • 13 Jan 2023
Topic Review
Water Physisorbed on Natural Clinoptilolite
Infrared spectroscopy (FT-IR) can provide very useful information on the nature of water physisorbed on zeolites. The vibrational characteristics of geomorphic clinoptilolite of natural origin and the water physically adsorbed on it have been investigated. In particular, two types of physisorbed water molecules have been identified by combining the FT-IR analysis with a mild thermal drying treatment (1h at 150°C) of the sample: the loosely-bound water and the tightly-bound water.
  • 2.1K
  • 29 Oct 2020
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.
  • 2.1K
  • 26 Jul 2021
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]. 
  • 2.1K
  • 26 Oct 2020
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.
  • 2.0K
  • 31 May 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.
  • 1.9K
  • 25 Jul 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.
  • 1.9K
  • 28 Oct 2020
Topic Review
Rhenium(I) Tricarbonyl Complexes As Photosensitisers
Photodynamic therapy (PDT) is emerging as a significant complementary or alternative approach for cancer treatment. Re(I) tricarbonyl complexes is a new generation of metal-based photosensitisers for PDT that are of great interest in multidisciplinary research.
  • 1.9K
  • 27 Oct 2020
Topic Review
Zirconolite and Murataite for the Immobilization of Actinides
Zirconolite is highly stable in nature, with isotope systems that have been closed for hundreds of million years, making it possible for age determination. Murataite is a very rare mineral, its synthetic counerpart was first discovered in the Synroc matrix from defense waste obtained by sintering. Synthetic zirconolie and murataite can be applied for nuclear waste immobilization. 
  • 1.9K
  • 14 Sep 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. 
  • 1.8K
  • 27 Apr 2022
Topic Review
Organometallic Chemistry of Guanidines
Guanidines, nitrogen-rich compounds, appear as one such potential alternatives as ligands or proligands. In addition to occurring in a plethora of natural compounds, and thus in compounds of pharmacological use, guanidines allow a wide variety of coordination modes to different metal centers along the periodic table, with their monoanionic chelate derivatives being the most common.
  • 1.8K
  • 18 Oct 2022
Topic Review
Structure and Properties of Graphene Quantum Dots
Graphene quantum dot (GQD) is a new type of carbon nanometer material. In addition to the excellent properties of graphene, it is superior due to the quantum limit effect and edge effect. Because of its advantages such as water solution, strong fluorescent, small size, and low biological toxicity, it has important application potential in various fields, especially in sensors and biomedical areas, which are mainly used as optical electrical sensors as well as in biological imaging and tumor therapy. In addition, GQDs have very important characteristics, such as optical and electrical properties. There are many preparation methods, divided into top-down and bottom-up methods, which have different advantages and disadvantages, respectively. In addition, the modification methods include heterogeneous doping, surface heterogeneity, etc. 
  • 1.8K
  • 17 Jan 2024
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).
  • 1.8K
  • 28 Feb 2022
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.
  • 1.7K
  • 07 Feb 2022
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.
  • 1.7K
  • 06 Jul 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.
  • 1.6K
  • 13 Apr 2022
Topic Review
Heteronuclear Metal Complexes with Anticancer Activity
Transition metal complexes have been deeply studied for different applications, such as catalysis, antimicrobial, and also antitumoral drugs. Platinum complexes are probably the most well-known and studied in the field of anticancer compounds, also thanks to the omnipresence of cisplatin and its derivatives as a starting point. Two promising new strategies to increase the efficacy of transition metal-based complexes have been described. First, the possibility of assembling two biologically active fragments containing different metal centres into the same molecule were considered, thus obtaining a heterobimetallic complex. Secondly, the conjugation of metal-based complexes to a targeting moiety was discussed.
  • 1.6K
  • 09 Jan 2023
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.
  • 1.5K
  • 06 Jun 2022
Topic Review
Graphene/Tourmaline-Composite-Modified Asphalt
In graphene/tourmaline-composite-modified asphalt, graphene can be used to further improve the road performance and emission reduction effect of tourmaline-modified asphalt. The temperature susceptibility, high temperature, anti-aging properties and rheological performance of the graphene/tourmaline-composite-modified asphalt are better than those of the tourmaline-modified asphalt and base asphalt. The asphalt fume reduction rate of graphene/tourmaline-composite-modified asphalt is higher than that of tourmaline-modified asphalt. With the increase of graphene content, the emission reduction performance increases gradually, and the enhancement effect of graphene on tourmaline performance is more obvious.
  • 1.5K
  • 24 Aug 2021
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