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Topic Review
Diatom-Based Biosensors
Porous materials showing some useful transducing features, i.e., any changes in their physical or chemical properties as a consequence of molecular interaction, are very attractive in the realization of sensors and biosensors. Diatom frustules have been gaining support for biosensors since they are made of nanostructured amorphous silica, but do not require any nano-fabrication step; their surface can be easily functionalized and customized for specific application; diatom frustules are photoluminescent, and they can be found in almost every pond of water on the Earth, thus assuring large and low-cost availability.
  • 1.7K
  • 31 Mar 2021
Topic Review
Formic Acid Dehydrogenation Using Noble-Metal Nanoheterogeneous Catalysts
Several obstacles remain in the way of widespread hydrogen use, most of which are related to transport and storage. Dilute formic acid (FA) is recognized asa a safe fuel for low-temperature fuel cells. FA is examined as a potential hydrogen storage molecule that can be dehydrogenated to yield highly pure hydrogen (H2) and carbon dioxide (CO2) with very little carbon monoxide (CO) gas produced via nanoheterogeneous catalysts.
  • 1.7K
  • 16 Mar 2022
Topic Review
Biochar Materials
Biochar (BC) based materials are solid carbon enriched materials produced via different thermochemical techniques such as pyrolysis.
  • 1.7K
  • 23 Feb 2023
Topic Review
Plate Heat Exchangers and Their Types of Construction
A plate heat exchanger (PHE) is a modern, effective type of heat transfer equipment capable of increasing heat recuperation and energy efficiency. For PHEs, enhanced methods of heat transfer intensification can be further applied using the analysis and knowledge already available in the literature.
  • 1.7K
  • 19 Jul 2023
Topic Review
Liquefied Dimethyl Ether Extraction Technology for Microalgae
Microalgae are a sustainable source for the production of biofuels and bioactive compounds. Dimethyl ether (DME), which is characterized by its low boiling point and safety as an organic solvent, exhibits remarkable properties that enable high extraction rates of various active compounds, including lipids and bioactive compounds, from high-water-content microalgae without the need for drying.
  • 1.7K
  • 30 Jan 2024
Topic Review
Cellulases
Cellulose is a macromolecular polysaccharide linked by glucose via a β-1,4-glycosidic bond, is insoluble in water and organic solvents, and forms the plant cell wall together with hemicellulose, pectin, and lignin. Cellulases are a group of enzymes that can hydrolyze the glycosidic bonds of cellulose to produce glucose, and the members of this group include exoglucanase, endoglucanase, and β-glucosidase. The synergistic action of these enzymes can break down cellulose into glucose.
  • 1.6K
  • 28 Jul 2021
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.
  • 1.6K
  • 23 Feb 2022
Topic Review
Baobab (Adansonia digitata L.)
Baobab (Adansonia digitata L.), which belongs to the Malvaceae family, is an indigenous African tree widespread in arid savannah regions of Madagascar, mainland Africa, the Arabian peninsula, and Australia, and it was once classified as the “lost crop” of Africa. 
  • 1.6K
  • 18 Oct 2021
Topic Review
Diffusion-Controlled Electrocrystallization Process
Electrocrystallization is a complicated multistep chain reaction involving the diffusion and mass transfer of ions in solution, the removal of solvation shells, electron transfer, the formation of surface adsorbed atoms, the clustering of adsorbed atoms, the generation of crystal nucleus, or embedding into existing lattice. A short historical background to study the nucleation and growth by diffusion-controlled electrocrystallization is provided.
  • 1.6K
  • 29 Aug 2022
Topic Review
Chemical Analysis of Synthetic Antioxidants in Foodstuffs
The information obtained by the systematic search in ScienceDirect® databases, indicated the predominance of the use of separation chromatography, followed by detection techniques in the development of analytical methods for the detection of phenolic antioxidants in foodstuffs. This is because these techniques allow the simultaneous determination of different types of antioxidants, through the separation of these compounds at different stages of a column, thus obtaining different retention times, which are related to the physicochemical characteristics of the antioxidants and their interaction between the stationary and mobile phase. After the separation, the antioxidants are identified and quantified using specific chromatographic detectors, such as ultraviolet–visible, diode array, thermal conductivity, and mass spectroscopy, resulting in a suitable sensitivity and selectivity. However, separation and detection chromatographic, despite being very accurate in the detection of antioxidants, have as their main disadvantage the use of large amounts of organic solvents or inert gases, with elevated purity and, consequently, high cost. Additionally, the use of these techniques requires rigorous steps of extraction and cleanup to prepare the foodstuff samples for analysis, remove interference compounds, and/or preconcentrate the antioxidants to obtain reliable information. Extraction steps can increase the time and costs in the analysis, promote a reduction in the analytical frequency, and generate a great quantity of residues, which goes against a very important principle, taken very seriously today, green chemistry, which orients the reduction or elimination of toxic residues in chemical products and processes, including all cycles of a chemical, in its design, manufacture, use, and final disposal.
  • 1.6K
  • 04 Nov 2022
Topic Review
Dehydrogenation and Oxidative Dehydrogenation of Propane to Propylene
Propylene is one of the most important building blocks in the petrochemical industry. It is industrially employed to produce polypropylene, which is used extensively to make packaging and labeling, textile products, laboratory equipment, loudspeakers, and automotive components. Propylene is also used for the manufacturing of acrylonitrile, propylene oxide derivatives, and other substances. Catalytic propane oxidative dehydrogenation (PODH) in the absence of gas phase oxygen is a promising approach for propylene manufacturing. PODH can overcome the issues of over-oxidation, which lower propylene selectivity. PODH has a reduced environmental footprint when compared with conventional oxidative dehydrogenation, which uses molecular oxygen and/or carbon dioxide.
  • 1.6K
  • 21 Jun 2022
Topic Review
Metal (Mo, W, Ti) Carbides for Dry Reforming
Dry reforming of hydrocarbons (DRH) is a pro-environmental method for syngas production. It owes its pro-environmental character to the use of carbon dioxide, which is one of the main greenhouse gases. Transition metal carbides (TMCs) can potentially replace traditional nickel catalysts due to their stability and activity in DR processes. 
  • 1.6K
  • 18 Jan 2022
Topic Review
Zeolites as Catalyst Supports for Hydrocarbon Oxidation Reactions
Catalytic oxidation is a key technology for the conversion of petroleum-based feedstocks into useful chemicals (e.g., adipic acid, caprolactam, glycols, acrylates, and vinyl acetate) since this chemical transformation is always involved in synthesis processes. Zeolites are microporous, crystalline aluminosilicate materials known since 1756 when the stilbite structure was identified by the Swedish mineralogist Crönstedt. Zeolites and other related porous materials can be supports for organometallic or metallic active species. These materials are the most studied supports due to their combined properties of mechanical and thermal stability that allows it an easy regeneration and recycling. 
  • 1.6K
  • 25 Mar 2022
Topic Review
Nanostructures Based on Cobalt Oxide
Cobalt oxide (Co3O4) is known to follow the spinel structure as (Co2+)[Co23+O4. The high spin Co2+occupies the interstitial sites of tetrahedral (8a) whereas low spin Co3+are known to occupy the interstitial sites of octahedral (16d) of the close-packed face-centered cubic lattice of CoO.Co2O3. The p-type conductivity of the material (CoO.Co2O3) is known to originate from the vacancies of Co in the crystal lattices or/and excess oxygen at interstitial sites.  Furthermore, 1D nanostructures of Co3O4  have been investigated over the past decades as an active material for chemical analytes detection owing to its superior catalytic effect together with its excellent stability.
  • 1.5K
  • 06 Aug 2021
Topic Review
Ion-Exchange Resins Application to Hydrogenation Reactions
The role of ion-exchange resins (IERs) as catalysts or catalysts supports, in hydrogenation reactions is revised and their potential application is presented. Both gel-type and macroreticular, basic or acid, IERs have been used for manifold metal-catalyzed hydrogenation processes in gas and liquid phase, including hydrogenation of alkenes, alkynes, carbonyls, arenes, nitroaromatics, and more.  Hydrogenation can be defined as the incorporation of hydrogen atoms, either from gaseous H2 or from other sources, to unsaturated compounds, that is compounds with double (C═C) or triple (C≡C) bonds, including those with carbonyl (C═O) or nitrile (C≡N) groups. The application of metal-doped IERs in hydrogenation reactions has been the focus of continuous attention for the research community with many relevant works published in the field.
  • 1.5K
  • 30 Mar 2023
Topic Review
Chemical Rings
The epoxidized group, also known as the oxirane group, can be considered as one of the most crucial rings in chemistry. Due to the high ring strain and the polarization of the C–O bond in this three-membered ring, several reactions can be carried out. One can see such a functional group as a crucial intermediate in fuels, polymers, materials, fine chemistry, etc. 
  • 1.5K
  • 30 Aug 2021
Topic Review
Membrane Technologies in Dairy Industry
Membrane technologies can be used in the dairy industry for many applications, such as milk clarification or fractioning and a concentration increase in specific components or the separation of them, since they cover a huge range of pore sizes (from 0 to 2 μm) and MWCOs (from 1 to 100,000 Da). For instance, MF can be used for fat globule (10 μm) fractionation as well as bacteria and spore (1 μm) removal. UF can be used for casein micelles (100 nm) or serum protein (10 nm) separation, whereas NF and RO can be used for lactose (1 nm), salt (0.1 nm) and water recovery.
  • 1.5K
  • 18 Nov 2021
Topic Review
Co-Torrefaction Progress of Biomass
The co-torrefaction of several biomasses may be a viable solution in the study area, as it produces biofuels and addresses waste-treatment concerns. Furthermore, the parameters of co-torrefaction, including temperature, reaction time, mass yield, energy yield, and the composition of the H/C and O/C ratio of the co-torrefied materials, are similar to those for coal composition. Different reactor types, such as fixed-bed, fluidized-bed, microwave, and batch reactors, are used for co-torrefaction, in which biomass blends with optimized blend ratios.
  • 1.5K
  • 29 Nov 2022
Topic Review
Concentrated Solar Power Technology in Photocatalytic Water Purification
Photocatalysis, a promising semiconductor-based technology activated by free and eternal solar energy, has great potential for addressing environmental remediation and energy conversion challenges. Concentrated solar power (CSP) technologies, namely parabolic trough reflectors, solar power towers, parabolic dish reflectors and linear Fresnel reflectors, exhibited excellent feasibility for boosting solar-driven photocatalytic processes. Based on the structural characteristics of CSP technologies, the CSP-based photocatalytic reactors could be divided into concentrated types and non/low-concentrated types. 
  • 1.5K
  • 23 Feb 2024
Topic Review
Biochar-Based Materials for Wastewater Treatment
Biochar is an important, interesting, low-cost material with various agricultural, industrial, and scientific applications. Biochar is a name given to vegetable-derived charcoal, which can be used as an agent to improve soil and water quality. This carbon-rich substance can be produced by the carbonization of biomass residues (e.g., wood, dung, manure, or leaves) in thermal conversion processes, such as pyrolysis, torrefaction, and hydrothermal carbonization (HTC). Among them, pyrolysis is the most common process to obtain biochar under anaerobic conditions and high temperatures. In addition, heat, syngas, liquid fuels, and pyroligneous acid (wood vinegar) are also generated during this process.
  • 1.5K
  • 18 Jan 2024
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