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Topic Review
Bioactive Glasses in Bone Regeneration
Mesoporous bioactive glasses (MBGs) is a category of bioceramics that, as will be explained, can be considered intermediate between traditional bioactive glasses—obtained by quenching of a melt or by the sol-gel method—and silica mesoporous materials. These bioactive glasses can be considered a spin-off of silica mesoporous materials because they are designed with a similar technical approach. Mesoporous glasses in addition to SiO2 contain significant amounts of other oxides, particularly CaO and P2O5 and therefore, they exhibit quite different properties and clinical applications than mesoporous silica compounds. Both materials exhibit ordered mesoporous structures with a very narrow pore size distribution that are achieved by using surfactants during their synthesis. The characteristics of mesoporous glasses made them suitable to be enriched with various osteogenic agents, namely inorganic ions and biopeptides as well as mesenchymal cells. 
  • 792
  • 19 Apr 2022
Topic Review
Separation and Recycling Potential of Rare Earth Elements
Rare earth elements (REEs) are key chemical raw materials in the development of low-carbon industrial processes and especially in green energy technologies. The REEs include 17 elements that can be found in nature (15 lanthanides La-Lu, Sc, and Y). They are ironically quite well represented in the Earth’s crust, except for the radioactive promethium, which is very rare. However, they are rarely found alone and at economically attractive concentrations, which make them expensive and complicated to extract and separate in high purity with conventional separation techniques. 
  • 792
  • 10 Mar 2022
Topic Review
Catalytic Activity of Zeolite
Zeolites are microporous aluminosilicates with high surface area and crystallinity. They have been widely applied in many different fields, such as gas storage, water treatment, biomass upgrading, and oil refining, because of their strong acidity, excellent catalytic activity, shape selectivity, and hydrothermal stability. In the past decades, one of the most important applications of zeolites is in fluidized catalytic cracking (FCC) in the petrochemical industry, which accounts for more than 95% of the global zeolite catalyst consumption. It is reported that 400 million tons of olefins are produced annually, and about 59% of olefins are produced by FCC units. Light olefins are critical building blocks in the petrochemical industry, and the demand for olefins and their derivatives has continuously increased over the last decade. Therefore, it is important to understand how to improve the catalytic performance of zeolites. Studies have shown that the performance of zeolite catalysts for cracking reactions is determined by various factors, including the porous size and composition, e.g., the Si/Al ratio and the presence of other heteroatoms or extra-framework aluminum (EFAL) species. Since the range of possible combinations of zeolite structures and compositions is exceedingly large, it is highly desirable to understand the effects of zeolite topology and composition on hydrocarbon cracking in order to improve their activity and selectivity to desired products.
  • 792
  • 09 Oct 2021
Topic Review
NIR-II Aggregation-Induced Emission Luminogens for Tumor Phototheranostics
Various modalities are involved in phototheranostic systems, including therapeutic methods such as photodynamic therapy (PDT) and photothermal therapy (PTT), and diagnostic technologies such as photothermal imaging (PTI), photoacoustic imaging (PAI), and fluorescence imaging (FLI). As an emerging strategy for cancer treatments via generating reactive oxygen species (ROS) with the assistance of light, tissue oxygen, and photosensitizer (PS), PDT has a remarkable light-controllable ability, specific spatiotemporal selectivity, and minimized invasiveness. Second near-infrared (NIR-II) fluorophores possess the capability of surmounting the inherent deficiencies of conventional FLI, by virtue of its remarkable features including deep penetration, reduced tissue scattering, minimal damage, and high spatial resolution endowed by the extremely long wavelength.
  • 792
  • 16 Feb 2022
Topic Review
Oligothiophene-Naphthalimide Hybrids Synthetic Approaches
Different variables were tuned in a series of organic semiconductors synthesized in the group of José L. Segura, such as the planarity and the length of their π-conjugated backbones, the topology and energy levels of the frontier molecular orbitals (HOMO and LUMO) and their molecular dipole moments. Studies carried out in the group of Rocío Ponce-Ortiz show that the tuning of these properties can be connected with the microstructure properties observed by atomic force microscopy (AFM) and X-ray diffraction (XRD) in thin films as well as with the performances in organic field-effect transistors (OFETs).
  • 791
  • 11 Jun 2021
Topic Review
Electrolyte Solvation Structure for Aqueous Zinc Ion Batteries
Zinc as an anode, with low potential (−0.762 V vs. SHE) and high theoretical capacity (820 mAh g−1 or 5854 mAh L−1), shows great promise for energy storage devices. The aqueous zinc ion battery (ZIB) is known as a prospective candidate for large-scale application in the future due to its high safety, environmental friendliness, abundant zinc resources on earth, and low-cost advantages. However, the existence of zinc dendrites and side reactions limit the practical application of ZIBs. Therefore, a lot of effort has been made to improve the performance from aspects including the structure design and surface modification of zinc anodes, regulation of the electrolyte solvation structure, and design of the functional separator.
  • 791
  • 09 Feb 2023
Topic Review
MoS2 Based Photodetectors
The properties of molybdenum disulfide (MoS2), such as direct band gap transition in low dimensional structures, strong light–matter interaction and good carrier mobility, combined with the possibility of fabricating thin MoS2 films, have attracted interest for this material in the field of optoelectronics. 
  • 791
  • 27 May 2021
Topic Review
Pt Nanocatalyst in Low Temperature Fuel Cells
Fuel cells (FCs) provide electricity via the generation of ion carriers by electrocatalysis at the electrodes as well as a positive or negative ion transport mechanism and direction of motion through electrolyte membranes. Pt nanomaterials are used in the catalytic layer components of low-temperature FCs associated with the clean H2 fuel industry, which are the most successful and typical examples of generating clean electric energy and power.
  • 791
  • 29 Mar 2022
Topic Review
Sustainability in Cosmetic Products
Characterize particulate matter (PM) concentrations released during the application of cosmetic powders, estimate the respiratory dosage for the different cosmetic powder types, and evaluate the sustainability based on the environmental and health effects.
  • 791
  • 26 Oct 2020
Topic Review
Photocatalytic Degradation of Antibiotics
Various methods, including carbon filtration, ozonation, catalytic membranes, Fenton-like catalysis, sorption, and biodegradation have been employed to eliminate such enduring antibiotic substances. As a result, wastewater accumulates effluents from corporations, clinics, and farmland. Sewage treatment is typically regarded as the preferred method for treating these antibiotics. Photocatalysis has gained a lot of interest as an effective method for eliminating antibiotic contaminants since it is inexpensive, effective, and environmentally benign as it eliminates antibiotics in sunlight and under ambient conditions. The reactions endured by a semiconductor and the potential to absorb photons with energies higher than its energy band gap is called “photocatalytic degradation”.
  • 790
  • 02 Mar 2023
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