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Topic Review
Supercritical Fluid Extraction as a Green Extraction
Extraction is a technique of isolating components from natural materials using chemical or physical methods. The world has turned to using green extraction as part of its efforts to preserve the environment. Green extraction is based on procedures that require less energy, allow for the use of alternative solvents and sustainable natural resources, and offer a safe and high-quality extract. Supercritical fluid extraction (SFE) procedures are compatible with the principles of green extraction.
  • 1.1K
  • 26 Oct 2022
Topic Review
Nuclear Resonance Vibrational Spectroscopy
Nuclear resonant vibrational spectroscopy (NRVS) is a synchrotron radiation (SR)-based nuclear inelastic scattering spectroscopy that measures the phonons (i.e., vibrational modes) associated with the nuclear transition. It has distinct advantages over traditional vibration spectroscopy and has wide applications in physics, chemistry, bioinorganic chemistry, materials sciences, and geology, as well as many other research areas.
  • 1.1K
  • 17 Aug 2021
Topic Review
Applications of Biodegradable Poly Blends/Composites
Biodegradable poly(ɛ-caprolactone) (PCL) and its composites or blends have received a lot of attention in the past because of their potential applications in human life and environmental remediation. Greater efforts have been made to develop biodegradable chemical materials as adsorbents that do not pollute the environment in order to replace traditional materials. 
  • 1.1K
  • 09 Nov 2023
Topic Review
Sol-Gel and Layer-by-Layer Coatings
The use of urface-engineered coatings for the fire protection of cotton fabrics is continously growing. In this context, two main approaches have been extensively investigated, namely sol-gel derived coatings and layer-by-layer assemblies. These approaches are both capable of providing treated fabrics with outstanding flame-retardant features, when exposed to a flame or an irradiative heat flux.  This review work aims at discussing the recent progresse with respect to both strategies, highlighting current limitations, open challenges, and possible further developments.
  • 1.1K
  • 01 Nov 2020
Topic Review
Historical Perspective on Membrane Science and Technology
Over the last few decades, considerable effort has been devoted to developing better membranes and extending their range of applications to different areas. Membrane processes already have an established role in gas separation and water treatment, and their applications in the food, pharmaceutical, and health areas have been continuously increasing. In the last few years, membrane processes proved to have a key role in biorefinery and bioenergy production processes, namely for process intensification and the recovery and purification of valuable products. Membranes are also a crucial component of electrochemical energy conversion devices, including fuel cells and electrolysers. Moreover, the growing environmental concerns have drawn attention to the use of fossil-based polymers and toxic solvents for membrane fabrication. Therefore, the development of new membranes, using polymers from renewable sources and more sustainable fabrication methods, is being pursued.
  • 1.1K
  • 23 Feb 2022
Topic Review
Cellulose Alcoholysis to Alkyl-levulinate Biofuels
Alkyl levulinates (ALs) represent outstanding bio-fuels and strategic bio-products within the context of the marketing of levulinic acid derivatives. In order to promote the market for these bio-products and, concurrently, the immediate development of new applications, it is necessary to speed up the intensification of their production processes. In this regard, today, it is possible to achieve this important issue only by using low-cost or, even better, waste biomasses, as starting feedstocks. Thus, the transition to the real biomass now represents a necessary choice for allowing the next ALs production on a larger scale. The improvement of the available synthetic strategies, the use of raw materials and the development of new applications for ALs can contribute to develop more intensified, greener and sustainable processes. 
  • 1.1K
  • 16 Dec 2020
Topic Review
Fischer–Tropsch Synthesis for Light Olefins
Light olefins as one the most important building blocks in chemical industry can be produced via Fischer–Tropsch synthesis (FTS) from syngas. FT synthesis conducted at high temperature would lead to light paraffins, carbon dioxide, methane, and C5+ longer chain hydrocarbons. The present work focuses on providing a critical review on the light olefin production using Fischer–Tropsch synthesis.
  • 1.1K
  • 07 Aug 2021
Topic Review
Trends in Cu-Catalyzed Ar-Xs Transformations with Amines
Aromatic compounds (Ar-Xs) are technologically important inert low-cost solvents (chlorobenzene or o-dichlorobenzene) and intermediates for the manufacture of flame-retardant polymers used in electronics and furniture. Furthermore, Ar-Xs are the chemicals necessary for the production of industrially important dyes, pigments, and a broad group of biologically active species such as pesticides and drugs. Utilization of Ar-Xs as arylating agents based on Cu-catalyzed substitution of bound halogen (X) applying different nucleophiles serves as the technique for production of a broad scale of useful chemicals.
  • 1.1K
  • 16 Sep 2022
Topic Review
Biodiesel as Renewable Biofuel in Current Diesel Engines
Many countries are immersed in several strategies to reduce the carbon dioxide (CO2) emissions of internal combustion engines. One option is the substitution of these engines by electric and/or hydrogen engines. However, apart from the strategic and logistical difficulties associated with this change, the application of electric or hydrogen engines in heavy transport, e.g., trucks, shipping, and aircrafts, also presents technological difficulties in the short-medium term. In addition, the replacement of the current car fleet will take decades. This is why the use of biofuels is presented as the only viable alternative to diminishing CO2 emissions in the very near future. Nowadays, it is assumed that vegetable oils will be the main raw material for replacing fossil fuels in diesel engines.
  • 1.1K
  • 13 May 2022
Topic Review
BODIPY-Based Molecules for Organic PhotoVoltaics
The 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)-based molecules have emerged as interesting material for optoelectronic applications. This type of structure is commonly described as an example of a “rigidified” monomethine cyanine dye or as a boradiazaindacene by analogy with the all-carbon tricyclic ring and the numbering of any substituents follows rule setup for the carbon polycycles (see COVER). This dye has also been  called “porphyrin’s little sister” and this happy definition has been so successful that in analogy with porphyrinic systems, the 8-position is often referred to as the meso site. The facile structural modification of BODIPY core provides an opportunity to fine-tune its photophysical and optoelectronic properties thanks to the presence of eight reactive sites which allows for the developing of a large number of functionalized derivatives for various applications. In particular, BODIPY dyes find increasing application in laser dyes, organic electronic (OLED and OPV), bioimmagining,  thanks to their properties  like high fluorescent quantum yield, sharp absorption and emission peak,  photostability and stability under physiological conditions. Because of this they can be used also  as probes for pH changes, detection of cations, anions and so on.
  • 1.1K
  • 01 Feb 2021
Topic Review
Bis-Chalcone-Based Photoinitiators of Polymerization
Over the past several decades, photopolymerization has become an active research field, and the ongoing efforts to develop new photoinitiating systems are supported by the different applications in which this polymerization technique is involved—including dentistry, 3D and 4D printing, adhesives, and laser writing.
  • 1.1K
  • 23 Jun 2021
Topic Review
Reaction Mechanisms of Glycerol Hydrogenolysis to 1,2-Propylene Glycol
The development and growth of the biodiesel industry has led to a parallel market for the supply of glycerol, its main by-product. Its wide availability and relatively low cost as a raw material make glycerol a basic component for obtaining various chemical products and allows for the development of a biorefinery around biodiesel plants, through the technological integration of different production processes. Catalytic hydrogenolysis is an interesting alternative because it leads to the formation of 1,2-propylene glycol (1,2-PG) and other glycols such as 1,3-propylene glycol (1,3-PG) and ethylene glycol (EG), widely used in the chemical industry. In the following text, the main reaction mechanisms of glycerol hydrogenolysis are presented, focusing on the production of 1,2-PG, in order of chronological appearance.
  • 1.1K
  • 10 May 2023
Topic Review
Activation Persulfate by Various Iron-Based Catalysts
Advanced oxidation technology of persulfate is a new method to degrade wastewater. As the economy progresses and technology develops, increasingly more pollutants produced by the paper industry, printing and dyeing, and the chemical industry are discharged into water, causing irreversible damage to water. Methods and research directions of activation persulfate for wastewater degradation by a variety of iron-based catalysts are reviewed. This entry describes the merits and demerits of advanced oxidation techniques for activated persulfate by iron-based catalysts. In order to promote the development of related research work, the problems existing in the current application are analyzed.
  • 1.0K
  • 24 Jan 2022
Topic Review
Megamolecular Polysaccharide Sacran
Natural polymer is a frequently used polymer in various food applications and pharmaceutical formulations due to its benefits and its biocompatibility compared to synthetic polymers. One of the natural polymer groups (i.e., polysaccharide) does not only function as an additive in pharmaceutical preparations, but also as an active ingredient with pharmacological effects.
  • 1.0K
  • 21 Jun 2021
Topic Review
Kaolinitic Raw Materials for Ceramics
Eight kaolinitic materials from the Lokoundje River at Kribi were sampled and investigated for their physical, chemical, mineralogical and thermal characteristics in order to evaluate their potential suitability as raw materials in ceramics. The Lokoundje kaolinitic materials are clayey to silty clayey and are predominantly composed of kaolinite and quartz. The alkali (Na2O + K2O) content ranges between 1 and 2.5 wt.%; these low values do not favor vitrification of the ceramics but may be improved through flux amendment. The presence of goethite in some samples limits their utilization in white ceramics. The minerals content, color, metallic sound, cohesion, linear shrinkage, flexural strength, bulk density, water absorption and microstructure were determined. The XRD data reveal that kaolinite and goethite were transformed, respectively, into mullite and hematite. The colors of the fired products are characteristic of their mineral assemblage. The metallic sound is indicative of low vitrification which is confirmed by the presence of cracks due to low flux contents. The cohesion is good to very good, due to the abundance of kaolinite. The physicomechanical properties increase with temperature as well as densification. The geochemical data show that the Lokoundje alluvial clays are suitable for the manufacture of white stoneware tiles. 
  • 1.0K
  • 09 Jul 2021
Topic Review
Treatment Methods for Dye-Contaminated Effluents
Advancements in textile dyeing technologies have introduced novel categories of dyes that have deleterious effects on ecosystems. Primarily, azo dyes represent the majority of synthetic dyes employed in textiles and in the realms of culinary and miscellaneous applications. Traditionally, these dyes infiltrate the environment via discharged contaminated effluents such as wastewater from industrial facilities. The contaminated discharged effluent exerts a pervasive impact on ecosystems, engendering pernicious afflictions in both human and faunal populations. Several treatment methodologies are employed for the eradication of contaminants from natural water resources and wastewater, encompassing all phases within water and wastewater treatment infrastructures. The evolution of each treatment stage is intricately linked to the escalating demand for potable water of impeccable quality. Water treatment methods such as Coagulation and Flocculation, Photocatalytic Degradation, Ion Exchange, Electrochemical Technique, Membrane Filtration, Electrodialysis Process, Biodegradation Techniques, and Adsorption are covered in detail, alongside the impacts of bio-based activated carbon as an adsorbent for azo dye. 
  • 1.0K
  • 26 Sep 2023
Topic Review
Aptamer-Sensors for Quantification of AFB1
Aflatoxin B1 (AFB1) is one of the most frequently-found mycotoxins in contaminated food. As the content of mycotoxins is particularly low in food, the development of probes to detect AFB1 in foods with high sensitivity and selectivity is an urgent social need for the evaluation of food quality. Numerous techniques have been developed to monitor AFB1. Nevertheless, most of them require cumbersome, labor-consuming, and sophisticated instruments, which have limited their application. An aptamer is a single, short nucleic acid sequence that is capable of recognizing different targets. Owing to their unique properties, aptamers have been considered as alternatives to antibodies. Aptasensors are considered to be an emerging strategy for the quantification of aflatoxin B1 with high selectivity and sensitivity. 
  • 1.0K
  • 19 Oct 2020
Topic Review
Electrostatic Repulsion Reversed-Phase Liquid Chromatography
Electrostatic Repulsion Reversed-Phase Liquid Chromatography (ERRP) allows the elution of bases in protonated form without peak distorsion (as commonly happen in reversed phase) due to the presence of positive charges in the chromatographic system. 
  • 1.0K
  • 05 Aug 2021
Topic Review
Natural and Semi-Synthetic Compounds for Wound Healing
Skin wounds are injuries that compromise or damage the structural integrity and optimal functioning of the skin and can be grouped into acute and chronic depending on the skin repair and recovery time frame. Specific interest is given to Aloevera, curcumin, cinnamaldehyde, polyhexanide, retinoids, ascorbate, tocochromanols, and chitosan. These compounds (when alone or in formulation with other biologically active molecules) could be a dependable alternative in the management or prevention of chronic wounds.
  • 1.0K
  • 27 Jun 2022
Topic Review
Ni-Based Bimetallic Catalysts
Metallic Ni shows high activity for a variety of hydrogenation reactions due to its intrinsically high capability for H2 activation, but it suffers from low chemoselectivity for target products when two or more reactive functional groups are present on one molecule. Modification by other metals changes the geometric and electronic structures of the monometallic Ni catalyst, providing an opportunity to design Ni-based bimetallic catalysts with improved activity, chemoselectivity, and durability.
  • 1.0K
  • 07 Feb 2022
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