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Topic Review
Uranium Sulfate
Uranium sulfate (U(SO4)2) is a water-soluble salt of uranium. It is a very toxic compound. Uranium sulfate minerals commonly are widespread around uranium bearing mine sites, where they usually form during the evaporation of acid sulfate-rich mine tailings which have been leached by oxygen-bearing waters. Uranium sulfate is a transitional compound in the production of Uranium hexafluoride. It was also used to fuel aqueous Homogeneous Reactors.
  • 492
  • 28 Oct 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.
  • 847
  • 31 May 2021
Topic Review
Tetrahedral Imidazolate Frameworks with Auxiliary Ligands
Zeolitic imidazolate frameworks (ZIFs) are an important subclass of metal–organic frameworks (MOFs).  A new kind of MOF, namely tetrahedral imidazolate frameworks with auxiliary ligands (TIF-Ax) was reported, by adding linear ligands (Hint) into the zinc–imidazolate system. Introducing linear ligands into the M2+-imidazolate system overcomes the limitation of imidazole derivatives. Thanks to the synergistic effect of two different types of ligands, a series of new TIF-Ax with interesting topologies and a special pore environment has been reported, and they have attracted extensive attention in gas adsorption, separation, catalysis, heavy metal ion capture, and so on.
  • 130
  • 07 Sep 2023
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.
  • 891
  • 24 Aug 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.
  • 651
  • 06 Jun 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. 
  • 115
  • 17 Jan 2024
Topic Review
Structure and Functions of Aβ and Tau Proteins
The amyloid hypothesis, i.e., the abnormal accumulation of toxic Aβ assemblies in the brain, has been considered the mainstream concept sustaining research in Alzheimer’s Disease (AD). However, the course of cognitive decline and AD development better correlates with tau accumulation rather than amyloid peptide deposition. Moreover, all clinical trials of amyloid-targeting drug candidates have been unsuccessful, implicitly suggesting that the amyloid hypothesis needs significant amendments. Accumulating evidence supports the existence of a series of potentially dangerous relationships between Aβ oligomeric species and tau protein in AD.
  • 512
  • 29 Aug 2022
Topic Review
Solketal
Solketal (CAS 100–79–8) has low viscosity at room temperature (~11 cP) and freezing, boiling, and flash points of about −26 °C, 190 °C, and 80 °C, respectively. The density is 1.06 g/cm3 and the vapor pressure is 107.32 mmHg. It has low toxicity, slight odor, and it is non-irritant for humans; due to these characteristics and to the renewable origin, it is considered an environmentally friendly substance. It is completely miscible in water and in most organic compounds, which endows its solvent capacity.
  • 2.6K
  • 07 May 2021
Topic Review
Sodium-Vanadium Bronze Na9V14O35
Na9V14O35 (η-NaxV2O5) has been synthesized by a solid-state route in an evacuated sealed silica tube and tested as electroactive material for Na half-cells. Being charged to 4.6 V vs. Na+/Na, almost 3 Na can be extracted per Na9V14O35 formula unit, resulting in a charge capacity of about 60 mAh g−1. Upon discharge below 1 V, Na9V14O35 uptakes Na up to the Na:V = 1:1 atomic ratio that is accompanied by a drastic increase of the separation between the layers of the VO4 tetrahedra and VO5 tetragonal pyramids, and a volume increase of about 31%. The induced structure instability triggers a transformation of the ordered layered Na9V14O35 structure into a rock-salt type disordered structure. Ultimately, the amorphous products of a conversion reaction are formed at 0.1 V, delivering the discharge capacity up to 490 mAh g−1, which, however, quickly fades with the number of charge-discharge cycles.
  • 447
  • 11 Jan 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.
  • 666
  • 06 Jul 2021
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