Topic Review
High-Temperature PEM Fuel Cells
This review summarizes the current status, operating principles, and recent advances in high-temperature polymer electrolyte membranes (HT-PEMs), with a particular focus on the recent developments, technical challenges and commercial prospects of the HT-PEM fuel cells. A detailed review of the most recent research activities has been covered by this work, with a major focus on the state-of-the-art concepts describing the proton conductivity and degradation mechanisms of HT-PEMs. Also, the fuel cell performance and the lifetime of HT-PEM fuel cells as a function of operating conditions have been discussed. In addition, the review will highlight the important outcomes found in recent literature about the HT-PEM fuel cell. The main objectives of this review paper will be as follows: (1) the latest development of the HT-PEMs, primarily based on polybenzimidazole membranes, (2) the latest development of the fuel cell performance and the lifetime of the HT-PEMs.
  • 1.0K
  • 28 Aug 2021
Topic Review
Cross-Coupling-Reaction of Copper Carbene Intermediate with Terminal Alkyne
Copper-catalyzed cross-coupling reaction of a copper carbene intermediate with terminal alkynes was one of the most powerful protocols for the construction of C–C bonds. However, in early works, a mixture of alkynoates and allenoates was generated in combined moderate yields under harsh reaction conditions. Until 2004, Fu reported the first example of the copper-catalyzed coupling reaction of terminal alkynes with diazo esters or diazo amides to yield 3-alkynoate or 3-butynamide products selectively with minimal amount of allene byproducts under no-basic conditions. Consequently, a variety of copper-catalyzed coupling reactions of terminal alkynes with various carbene precursors have been developed independently.
  • 1.0K
  • 30 May 2022
Topic Review
CuInS-Based Ternary Quantum Dots
The clinical translation of quantum dots (QDs) has gained much importance for the biomedical application. But the most used conventional QDs contains toxic heavy metals such as Pb, Cd and Hg. Hence, there is a need for an alternative material with similar optical properties and low cytotoxicity.  Among these materials, CuInS2 (CIS) QDs has attracted a lot of interest due to its direct bandgap in the infrared region, large optical absorption coefficient and low toxic composition. All these make it a good material for biomedical application. For further research on the material, there is a need for a critical review which summarise the various synthetic strategies, surface modification and Biological evaluation involved with CIS QDs. 
  • 1.0K
  • 02 Nov 2020
Topic Review
Micro-Computed Tomography
Micro-computed tomography (micro-CT) is a consolidated imaging technology allowing non-destructive three-dimensional (3D) qualitative and quantitative analysis by the observation of microstructures with high resolution. This paper Ten Years of Micro-CT in Dentistry and Maxillofacial Surgery: A Literature Overview aims at delivering a structured overview of literature about studies performed using micro-CT in dentistry and maxillofacial surgery (MFS) by analyzing the entire set of articles to portray the state of the art of the last ten years of scientific publications on the topic. 
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  • 23 Feb 2021
Topic Review
High Performance Polymer Composites
Summarize data on the structure, mechanical and tribological properties, and wear patterns of composites based on high-performance polymers (HPPs) intended for use in friction units. The three key sections, divided according to the tribological contact schemes regardless of the polymer matrix. In the second part, the analysis of composites is carried out in point contacts. The third section is devoted to the results of studies of HPP-based composites in linear ones. The fourth section summarizes information on flat contacts. Particular attention is paid to the formation of transfer films (TFs) in the contacts and their influence on the tribological patterns of the studied rubbing materials.
  • 1.0K
  • 16 Mar 2022
Topic Review
TiO2 Microscale Structures
TiO2 microscale structures can be prepared from both TiO2 precursors and TiO2 nanoparticles (NPs). TiO2 microscale structures have many advantages compared to TiO2 NPs powders, such as tunable structure, higher photocatalytic activity, and ease of recovery. For TiO2 microscale structures, solid spheres and hollow spheres share some similar synthesis methods. However, microscale TiO2 microscale structures are not easily mass-produced due to the complexity of the synthesis process.
  • 1.0K
  • 26 Oct 2020
Topic Review
Switchable Solvents
Switchable solvents are a special class of solvents that have the ability to switch between different forms and properties, depending on external stimuli. The most common type of switchable solvents are called "ionic liquids" which are liquids made up of ions that are in a liquid state at room temperature. These solvents have unique properties that make them attractive for a wide range of applications, such as green chemistry, separation and purification processes, and energy storage. Switchable solvents are a class of solvents that can undergo reversible changes in their physical and chemical properties in response to external stimuli, such as temperature, pressure, or pH. They have gained significant attention in recent years due to their potential as more sustainable and efficient alternatives to traditional solvents in a range of applications, including industrial processes and chemical synthesis. Switchable solvents can be classified into two main categories: reversible ionic liquids (RILs) and switchable polarity solvents (SPSs). RILs are a type of switchable solvent that can change from a liquid to a solid or a gas, depending on the applied stimulus. This reversible phase transition is due to the formation or disruption of ionic interactions between the solvent molecules. RILs have been used in a range of applications, including the separation of chemicals, catalysis, and energy storage. SPSs, on the other hand, are solvents that can switch between polar and non-polar states in response to a stimulus, such as a change in pH or temperature. This switch in polarity can be used to selectively extract or dissolve different types of molecules, making them useful in a range of industrial processes, including extraction, separation, and purification. One of the main advantages of switchable solvents is their potential to reduce the environmental impact of chemical processes by replacing traditional solvents that are toxic or have a high carbon footprint. They can also improve process efficiency by reducing the need for multiple solvents and simplifying the solvent recovery process
  • 1.0K
  • 24 Mar 2023
Topic Review
Curing
Curing is a chemical process employed in polymer chemistry and process engineering that produces the toughening or hardening of a polymer material by cross-linking of polymer chains. Even if it is strongly associated with the production of thermosetting polymers, the term "curing" can be used for all the processes where a solid product is obtained from a liquid solution, such as will PVC plastisols.
  • 1.0K
  • 26 Oct 2022
Topic Review
Surface-Functionalized Separator
The surface-modified separator plays a role in improving the electrolyte wettability, homogenizing Li+flux, and strengthening the mechanical/thermal property. Due to these favorable benefits, the formation of sharp Li dendrite is efficiently suppressed and the thermal stability of battery is greatly enhanced. In this article, separator-coating materials are classified into six categories in terms of material characteristics to show how each material has different electrochemical properties. We believe that the suggested approach would become a powerful strategy to improve the performance and stability of next-generation batteries such as lithium-metal batteries.
  • 1.0K
  • 23 Sep 2021
Topic Review
Coumarin Derivatives from Marine World
Coumarin and its derivatives have significantly attracted the attention of medicinal chemists and chemical biologists due to their huge range of biological, and in particular, pharmacological properties. Interesting families of coumarins have been found from marine sources, which has accelerated the drug discovery process by inspiring innovation or even by the identification of analogues with remarkable biological properties.
  • 1.0K
  • 13 Jan 2023
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