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Topic Review
Metal–Organic Framework-Based Membranes for Gas Separation
Metal–organic frameworks (MOFs) represent the largest class of materials among crystalline porous materials ever developed, and have attracted attention as core materials for separation technology. Their extremely uniform pore aperture and nearly unlimited structural and chemical characteristics have attracted great interest and promise for applying MOFs to adsorptive and membrane-based separations. 
  • 1.4K
  • 28 Feb 2024
Topic Review
Gold and Silver Nanoparticle-Based Colorimetric Sensors
Gold and Silver nanoparticles (AuNPs and AgNPs) are perfect platforms for developing sensing colorimetric devices thanks to their high surface to volume ratio and distinctive optical properties, particularly sensitive to changes in the surrounding environment. These characteristics ensure high sensitivity in colorimetric devices. Au and Ag nanoparticles can be capped with suitable molecules that can act as specific analyte receptors, so highly selective sensors can be obtained.
  • 1.4K
  • 23 Nov 2021
Topic Review
Reaction Mechanism of Olefins
Light olefins (C2-C4) are important C-building blocks which are currently used to produce a variety of chemicals, such as elastomers, medicines, cosmetics, detergents, solvents, etc. They can be produced by steam cracking, fluid catalytic cracking of naphtha, direct/indirect conversion of synthesis gas (CO + H2) or by hydrogenation of CO2 using H2 from renovable energy sources. However, the catalytic production of light olefins from CO2 is difficult due to the chemical inactivity of CO2 molecule, the high C-C coupling barrier and the necesity to limit the formation of C-C bond and methane. Therefore, the catalysts required for this reaction must to be multifunctional and have an optimized amount of active sites. 
  • 1.4K
  • 29 Nov 2021
Topic Review
Solar Energy Systems into Seawater Desalination
Solar energy, amongst all renewable energies, has attracted inexhaustible attention all over the world as a supplier of sustainable energy. The energy requirement of major seawater desalination processes such as multistage flash (MSF), multi-effect distillation (MED) and reverse osmosis (RO) are fulfilled by burning fossil fuels, which impact the environment significantly due to the emission of greenhouse gases. The integration of solar energy systems into seawater desalination processes is an attractive and alternative solution to fossil fuels. 
  • 1.4K
  • 29 Sep 2022
Topic Review
Naringin
Polyphenols comprise a number of natural substances, such as flavonoids, that show interesting biological effects. Among these substances is naringin, a naturally occurring flavanone glycoside found in citrus fruits and Chinese medicinal herbs. Several studies have shown that naringin has numerous biological properties, including cardioprotective, cholesterol-lowering, anti-Alzheimer’s, nephroprotective, antiageing, antihyperglycemic, antiosteoporotic and gastroprotective, anti-inflammatory, antioxidant, antiapoptotic, anticancer and antiulcer effects. Despite its multiple benefits, the clinical application of naringin is severely restricted due to its susceptibility to oxidation, poor water solubility, and dissolution rate.
  • 1.4K
  • 24 Mar 2023
Topic Review
Water Remediation
Chemical pollution of water has raised great concerns among citizens, lawmakers, and nearly all manufacturing industries. As the legislation addressing liquid effluents becomes more stringent, water companies are increasingly scrutinized for their environmental performance. In this context, emergent contaminants represent a major challenge, and the remediation of water bodies and wastewater demands alternative sorbent materials. One of the most promising adsorbing materials for micropolluted water environments involves cyclodextrin (CD) polymers and cyclodextrin-containing polysaccharides. 
  • 1.4K
  • 22 Feb 2021
Topic Review
Perezhivanie and Its Application
Perezhivanie is a concept that was originally defined by Vygotsky, but it did not become a part of educational theory until recently. Today the concept has been revived, and it is now used as a way to include emotional aspects into education and educational research. The concept also provides a rationale for describing and forming personalised learning.
  • 1.4K
  • 17 Jan 2022
Topic Review
Alginate Application in Drug Delivery
Alginates are generally used in the food, beverage, cosmetic, paper, textile printing, and pharmaceutical industries. They have been utilized as stabilizers, thickeners, emulsifiers, and hydration and gelling agents. The main use of alginate in the biomedical industry is mainly focused on hydrogels used in wound healing, drug delivery, and tissue regeneration. The broad range of applications is due to its biocompatibility, low toxicity and relatively low-cost consumption, and structural similarity to the extracellular matrices of living tissue.
  • 1.4K
  • 22 Dec 2021
Topic Review
Metal Organic Frameworks
Metal–organic frameworks (MOFs) are a family of porous crystalline materials that serve in some cases as versatile platforms for catalysis. 
  • 1.3K
  • 13 Dec 2021
Topic Review
Recent Advances in A3 Coupling with Metal Salts
Recent advances in the metal salt catalysed multicomponent reaction of aldehydes, amines, and alkynes, known as A3 coupling, which yields propargylamines, a valuable organic scaffold.
  • 1.3K
  • 04 Jul 2022
Topic Review
Hydrogen Adsorption in Metal–Organic Frameworks
The development of hydrogen technologies and a wider use of hydrogen fuel cell systems require new materials that can store large amounts of hydrogen at relatively low pressures with small volume, low weight, and fast kinetics for recharging. Among the most challenging materials for hydrogen storage are porous coordination polymers, also called metal–organic frameworks (MOFs). MOFs are two- or three-dimensional porous crystalline materials with infinite lattices. As a result of their ultra-high surface area values (more than 2500 m2·g–1 measured by the Brunauer–Emmett–Teller (BET) approach), they were found to be promising gas adsorbers for small gaseous molecules, including CH4, CHCl3, CCl4, C6H6, C6H12, CO2, Ar, N2, and H2. The main benefit of MOFs is their reversible and high-rate hydrogen adsorption process. A reasonable number of H2 molecules inside the body of MOFs may only be obtained at very low temperatures. To date, MOFs have shown significant progress in applications of gas separation, catalysis, and coordination chemistry.
  • 1.3K
  • 09 Aug 2021
Topic Review
Zeolite/Pharmaceuticals System
Zeolites belong to aluminosilicate microporous solids, with strong and diverse catalytic activity, which makes them applicable in almost every kind of industrial process, particularly thanks to their eco-friendly profile. Another crucial characteristic of zeolites is their tremendous adsorption capability. Therefore, it is self-evident that the widespread use of zeolites is in environmental protection, based primarily on the adsorption capacity of substances potentially harmful to the environment, such as pharmaceuticals, pesticides, or other industry pollutants. On the other hand, zeolites are also recognized as drug delivery systems (DDS) carriers for numerous pharmacologically active agents. The enhanced bioactive ability of DDS zeolite as a drug carrying nanoplatform is confirmed, making this system more specific and efficient, compared to the drug itself. These two applications of zeolite, in fact, illustrate the importance of (ir)reversibility of the adsorption process. 
  • 1.3K
  • 11 Aug 2022
Topic Review
Bucherer–Bergs Multicomponent Synthesis of Hydantoins
The Bucherer–Bergs reaction is one of the most convenient general methods for the preparation of 5-substituted and 5,5-disubstituted hydantoins (imidazolidine-2,4-diones, 2,4-dioxoimidazolidines). Generally, in this multicomponent reaction, the aldehyde or ketone in aqueous ethanol is heated at 60–70° with potassium (or sodium) cyanide and ammonium carbonate to produce directly hydantoins 1.
  • 1.3K
  • 28 Jul 2021
Topic Review
Processes for Obtaining Syngas and Hydrogen
The growing demand for high-quality chemical products has already stimulated an increased interest in the conversion of hydrocarbon gases (natural gas, methane, biogas) into motor fuels and high value-added chemical products, as well as into hydrogen, which is increasingly in demand on the market. The conversion of natural gas into hydrogen and syngas is still the most complex and costly stage of modern gas chemical processes, the low efficiency of which hinders the development of modern gas chemistry. 
  • 1.3K
  • 14 Apr 2023
Topic Review
Thiol-and Disulfide-Based Stimulus-Responsive Soft Materials
Thiols (RSH) and disulfides (RSSR) are components of many proteins, biopolymers, and biomolecules.  Many can be interconverted by simple oxidation and reduction reactions that change drastically their properties and those of host molecules of which they are a part.
  • 1.3K
  • 11 Jun 2021
Topic Review
Surface Acoustic Wave Sensors Materials
Since their development, surface acoustic wave (SAW) devices have attracted much research attention due to their unique functional characteristics, which make them appropriate for the detection of chemical species. The scientific community has directed its efforts toward the development and integration of new materials as sensing elements in SAW sensor technology with a large area of applications.
  • 1.3K
  • 28 Jun 2021
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
  • 1.3K
  • 24 Mar 2023
Topic Review
Cannabinoid Receptor Antagonist
A cannabinoid receptor antagonist, also known simply as a cannabinoid antagonist or as an anticannabinoid, is a type of cannabinoidergic drug that binds to cannabinoid receptors (CBR) and prevents their activation by endocannabinoids. They include antagonists, inverse agonists, and antibodies of CBRs. The discovery of the endocannabinoid system led to the development of CB1 receptor antagonists. The first CBR inverse agonist, rimonabant, was described in 1994. Rimonabant blocks the CB1 receptor selectively and has been shown to decrease food intake and regulate body-weight gain. The prevalence of obesity worldwide is increasing dramatically and has a great impact on public health. The lack of efficient and well-tolerated drugs to cure obesity has led to an increased interest in research and development of CBR antagonists. Cannabidiol (CBD), a naturally occurring cannabinoid, is a non-competitive CB1/CB2 receptor antagonist. And Δ9-tetrahydrocannabivarin (THCV), a naturally occurring cannabinoid, modulate the effects of THC via direct blockade of cannabinoid CB1 receptors, thus behaving like first-generation CB1 receptor inverse agonists, such as rimonabant. CBD is a very low-affinity CB1 ligand, that can nevertheless affect CB1 receptor activity in vivo in an indirect manner, while THCV is a high-affinity CB1 receptor ligand and potent antagonist in vitro and yet only occasionally produces effects in vivo resulting from CB1 receptor antagonism. THCV has also high affinity for CB2 receptors and signals as a partial agonist, differing from both CBD and rimonabant.
  • 1.3K
  • 08 Nov 2022
Topic Review
Sample Preparation for Cosmetics Analysis
Traditional cosmetics sample preparation techniques involve liquid–liquid extraction (LLE) and solid–liquid extraction (SLE). In last years, modern sample extraction techniques are advancing towards fast sample processing, easy automatization, as well as a reduction in organic solvent volumes, in agreement with the green chemistry principles in two ways (i) the miniaturization of conventional procedures allowing a reduction of the solvents and reagents consumption and (ii) the development and application of sorbent- and liquid-based microextraction technologies to obtain a high analyte enrichment, avoiding or significantly reducing the use of organic solvents.
  • 1.3K
  • 24 Nov 2021
Topic Review
Screen-Printed Electrodes as Transducers
In the last decades, sensors based on screen-printed electrodes (SPEs) have gained increasing importance because of their advantageous characteristics, such as low-cost, disposability, ease of use and portability, which allow fast analysis in point-of-need scenarios. The main characteristics of SPEs as electrochemical transducers for biosensors are described below.
  • 1.3K
  • 13 Apr 2021
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