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Topic Review
Epoxides Cycloaddition for CO2 Utilization
In the present review (10.3390/pr8050548), CO2 cycloaddition can be seen as a reasonably competent alternative to CO2 transformation, offsetting the high value-added nature by extending material use defer CO2 back to the atmosphere when compared to commodities and fuels such as urea, methanol, and methane.
  • 2.9K
  • 27 Aug 2020
Topic Review
Lipids in Food Flavor Generation
Lipids in food are a source of essential fatty acids and also play a crucial role in flavor and off-flavor development. Lipids contribute to food flavor generation due to their degradation to volatile compounds during food processing, heating/cooking, and storage and/or interactions with other constituents developed from the Maillard reaction and Strecker degradation, among others. The degradation of lipids mainly occurs via autoxidation, photooxidation, and enzymatic oxidation, which produce a myriad of volatile compounds. The oxidation of unsaturated fatty acids generates hydroperoxides that then further break down to odor-active volatile secondary lipid oxidation products including aldehydes, alcohols, and ketones.
  • 2.8K
  • 15 Aug 2022
Topic Review
Compositional Engineering of Perovskites
We give a systematic overview of compositional engineering by distinguishing the different defect-reducing mechanisms. Doping effects are divided into influences on: (1) crystallization; (2) lattice properties. Incorporation of dopant influences the lattice properties by: (a) lattice strain relaxation; (b) chemical bonding enhancement; (c) band gap tuning. The intrinsic lattice strain in undoped perovskite was shown to induce vacancy formation. The incorporation of smaller ions, such as Cl, F and Cd, increases the energy for vacancy formation. Zn doping is reported to induce strain relaxation but also to enhance the chemical bonding. The combination of computational studies using (DFT) calculations quantifying and qualifying the defect-reducing propensities of different dopants with experimental studies is essential for a deeper understanding and unraveling insights, such as the dynamics of iodine vacancies and the photochemistry of the iodine interstitials, and can eventually lead to a more rational approach in the search for optimal photovoltaic materials.
  • 2.8K
  • 28 Oct 2020
Topic Review
Removal of Purines from Beer
Beer corresponds to a fermented alcoholic beverage composed of several components, including purine compounds. These molecules, when ingested by humans, can be catabolized into uric acid, contributing to uric acid’s level increase in serum, which may lead to hyperuricemia and gout. To assure a proper management of this disease, physicians recommend restrictive dietary measures, particularly by avoiding the consumption of beer. Therefore, it is of relevance to develop efficient methods to remove purine compounds from alcoholic beverages such as beer. There are several enzymatic, biological, and adsorption methods reported envisaging purine compounds’ removal. Some enzymatic and biological methods present drawbacks, which can be overcome by adsorption methods. Within adsorption methods, adsorbent materials, such as activated carbon or charcoal, have been reported and applied to beer or wort samples, showing an excellent capacity for adsorbing and removing purine compounds. By ensuring the selective removal of purine compounds from this beverage, beer can be taken by hyperuricemic and gouty patients, avoiding restrictive dietary measures, while decreasing the related healthcare economic burden. 
  • 2.8K
  • 23 Nov 2021
Topic Review
Biofilm and Pathogen Inhibition in Cooling Towers Using Natural Chemistry
Industrial comfort cooling and process cooling typically employ water evaporative cooling towers (CTs) to dissipate reject heat.  This warm water, enriched with nutrient materials scrubbed from the air or in source water, provides a nurturing environment for a wide variety of neutrophilic microorganisms, some of which are human pathogens.  For example, cases of Legionella pneumophila infection have been traced to CT Systems that have become pubic hazards in recent years.  Typically, one or more toxic microbicides are applied to control the problem.  This article highlights two case studies that utilize ultra-softened (<0.3 mg/L total hardness), highly-concentrated chemical components, naturally present in almost all makeup water sources used by CT Systems, that can generate high-pH, high-TDS cooling water.  At sufficient concentrations, these two natural parameters are hostile to microorganisms, including protozoa and slime-forming (biofilm) bacteria that harbor pathogens.  Field testing for Adenosine Tri-Phosphate (ATP), reported in Relative Light Units (RLU), provides a quick, sensitive method to detect all water-borne microbiological activity present in CT Systems and verifies the effectiveness of the anti-microbial program by quantifiable data, reported as ATP-RLU.
  • 2.8K
  • 28 Oct 2020
Topic Review
Propylene Synthesis
Propylene is one of the most important feedstocks in the chemical industry, as it is used in the production of widely diffused materials such as polypropylene. Conventionally, propylene is obtained by cracking petroleum-derived naphtha and is a by-product of ethylene production. To ensure adequate propylene production, an alternative is needed, and propane dehydrogenation is considered the most interesting process.
  • 2.6K
  • 25 Oct 2021
Topic Review
Citrus Waste
The scientific name of citrus is Citrus L. and it belongs to the Rutaceae family. It is one of the most important fruit crops that is grown throughout the world. During processing, a large amount of waste is produced from citrus fruits in the form of peel, seeds, and pomace. Every year, the citrus processing industry creates a large amount of waste. The citrus waste is composed of highly bioactive substances and phytochemicals, including essential oils (EOs), ascorbic acid, sugars, carotenoids, flavonoids, dietary fiber, polyphenols, and a range of trace elements.
  • 2.6K
  • 22 Feb 2023
Topic Review
Palm Oil Mill Effluent Treatment
POME is considered as one of the major problems that has generated voluminously from the palm oil industries. Pre-treatment is utmost required prior discharge to the environment. This review deals with current POME treatment techniques.
  • 2.6K
  • 26 May 2021
Topic Review
Lignin Biopolymer in Biomaterials Synthesis
Lignin is one of the wood and plant cell wall components that is available in large quantities in nature. Its polyphenolic chemical structure has been of interest for valorization and industrial application studies. Lignin can be obtained from wood by various delignification chemical processes, which give it a structure and specific properties that will depend on the plant species. Due to the versatility and chemical diversity of lignin, the chemical industry has focused on its use as a viable alternative of renewable raw material for the synthesis of new and sustainable biomaterials. 
  • 2.5K
  • 08 Apr 2021
Topic Review
Advantages and Disadvantages of Fenton Process
The Fenton reaction is primarily based on the idea of the formation of oxidizing radicals, which are created by the catalytic action of Fe2+ on the decomposition of H2O2, added in a certain amount and ratio to water, which also contains various organic substances. Oxidative radicals oxidize the present organic substances to varying degrees during the momentary period of their existence. This Fenton reaction is homogeneous because the catalyst (Fe2+ ion) is dissolved in water. However, the catalyst can also be heterogeneous. 
  • 2.5K
  • 22 Feb 2023
Topic Review
Polymers Modifications through Ultraviolet Absorbers Addition
The photooxidative degradation process of plastics caused by ultraviolet irradiation leads to bond breaking, crosslinking, the elimination of volatiles, formation of free radicals, and decreases in weight and molecular weight. Photodegradation deteriorates both the mechanical and physical properties of plastics and affects their predicted life use, in particular for applications in harsh environments. Plastics have many benefits, while on the other hand, they have numerous disadvantages, such as photodegradation and photooxidation in harsh environments and the release of toxic substances due to the leaching of some components, which have a negative effect on living organisms. Therefore, attention is paid to the design and use of safe, plastic, ultraviolet stabilizers that do not pose a danger to the environment if released. Plastic ultraviolet photostabilizers act as efficient light screeners (absorbers or pigments), excited-state deactivators (quenchers), hydroperoxide decomposers, and radical scavengers. Ultraviolet absorbers are cheap to produce, can be used in low concentrations, mix well with polymers to produce a homogenous matrix, and do not alter the color of polymers.
  • 2.4K
  • 10 Jan 2022
Topic Review
Imidazoline Surfactants
Imidazoline surfactants are a class of surfactants with a hydrophobic tail and an imidazoline hydrophilic head. They are commonly used as emulsifiers, wetting agents, and cleaning agents in a variety of applications, including personal care, industrial cleaning, and agriculture. Imidazoline surfactants are known for their stability in acidic and alkaline conditions, making them a popular choice for many industrial processes. Imidazoline surfactants are mainly the cationic surfactants that contain an imidazoline ring in their chemical structure. They are commonly used as emulsifiers, corrosion inhibitors, and wetting agents in a variety of industrial and household applications. Imidazoline surfactants are typically synthesized by reacting a fatty acid or fatty amine with an imidazole or imidazoline compound. The resulting surfactants have a unique combination of properties, including excellent emulsification, wetting, and corrosion inhibition abilities.
  • 2.3K
  • 24 Mar 2023
Topic Review
Catalysts for Synthesis of Ethylene-Propylene-Diene Rubbers
Ethylene-propylene-diene rubbers (EPDM) are one of the most important polyolefin materials widely commercialized and used in various industries in recent years. The production of EPDM is based solely on catalytic coordination polymerization processes. The development of new catalysts and processes for the synthesis of EPDM has expanded the range of products and their manufacturing in terms of energy efficiency, processability, and environmental safety.
  • 2.2K
  • 13 Sep 2022
Topic Review
Processing Properties of Starch
Starch is the second most abundantly available natural polymer in the world, after cellulose. If we add its biodegradability and non-toxicity to the natural environment, it becomes a raw material very attractive for the food and non-food industries. However, in the latter case, mainly due to the high hydrophilicity of starch, it is necessary to carry out many more or less complex operations and processes. One of the fastest growing industries in the last decade is the processing of biodegradable materials for packaging purposes. This is mainly due to awareness of producers and consumers about the dangers of unlimited production and the use of non-degradable petroleum polymers.
  • 2.2K
  • 05 Apr 2021
Topic Review
β-Ionone
β-Ionone is a natural plant volatile compound, and it is the 9,10 and 9′,10′ cleavage product of β-carotene by the carotenoid cleavage dioxygenase. β-Ionone is widely distributed in flowers, fruits, and vegetables. β-Ionone and other apocarotenoids comprise flavors, aromas, pigments, growth regulators, and defense compounds; serve as ecological cues; have roles as insect attractants or repellants, and have antibacterial and fungicidal properties. In recent years, β-ionone has also received increased attention from the biomedical community for its potential as an anticancer treatment and for other human health benefits. However, β-ionone is typically produced at relatively low levels in plants. Thus, expressing plant biosynthetic pathway genes in microbial hosts and engineering the metabolic pathway/host to increase metabolite production is an appealing alternative.
  • 2.1K
  • 26 Apr 2021
Topic Review
Metal Current Collector for LMBs
Lithium Metal Anode (LMA) has been considered as the promising candidate, owing to their high theoretical gravimetric capacity, low electrochemical potential, and low density, to replace the conventional carbon based anode materials of lithium-ion batteries (LIBs). Unfortunately, the inherent hyperactive and volume expansion issues of Lithium (Li) leads to the formation of notorious Li dendrite growth and unstable solid-electrolyte-interphase (SEI), eventually hindering the practical application of lithium metal batteries (LMBs). To resolve this issue, one of the effective approach is to engineer three dimensional (3D) porous metal based Li host owing to their chemical and mechanical stability, high electronic conductivity and low cost. In this review, the challenges and strategies to suppress the Li dendrite growth are presented. Then the design principles and effectiveness of different kinds of metal based Li host to accommodate and buffer the volume expansion of Li for guiding the uniform Li deposition  are summarized. Then the special attention is paid to the lithiophilic coating or decoration which can further control the initial Li deposition and lowers the nucleation and voltage overpotential in 3D porous metal framework during Li plating/stripping cycles. Finally, the conclusion and perspective are given on the current status, challenges and future  research pathway toward advancement of LMA for dendrite-free and improved battery performance.
  • 2.1K
  • 28 Oct 2020
Topic Review
Aromatic Water Pollutants
In recent years, the intensification of human activities including rapid urbanization, industrialization, population, and economic growth, led to an increase in waste production and energy demand. Most importantly such activities pose concerns for health, energy security and climate changes. Hazardous volatile organic compounds, VOC, and aromatic organic compounds, AOC, are being generated from the activities of many vital industries like mining and petrochemicals. They are instrumental in the economic growth of many countries and their products are regarded as privileges to modern communities. Nevertheless, they are toxic and carcinogenic thus, these wastes have been classified as “hazardous”. The simultaneous treatment of organic pollutants and energy recovery is an attractive solution to reduce pollution in water, air, and soil as well as provide alternative clean energy sources. Hydrogen could be generated from organic pollutants in water through photocatalysis. Photocatalysis refers to the oxidation and reduction, redox, reactions on semiconductor surfaces, mediated by the valence band holes and conduction band electrons, which are generated by the absorption of ultraviolet or visible light radiation. Compared to traditional oxidation processes, photocatalytic redox reaction operates at ambient conditions without a high temperature or high pressure, and many recalcitrant organic contaminants can be degraded without the addition of chemical oxidants, hence it is fully green process. Among the various photocatalysts, TiO2, as the most widely employed “golden” photocatalyst, has been largely used in photocatalysis, due to its chemical stability, nontoxicity, and low cost. In the last two decades, TiO2 photocatalysis has expanded very quickly, having undergone various development‐related energy issues and environmental issues, such as direct solar H2O splitting into H2 and the decomposition of pollutants in air and H2O at low concentrations. Although great progress has been made in TiO2 photocatalysis, much remains unknown, which raises an interesting challenge not only for engineers but also for basic scientists. a typical photocatalytic reaction in TiO2 photocatalysis contains many fundamental processes, including charge carrier formation, separation, relaxation, trapping, transfer, recombination, and transportation.
  • 2.1K
  • 24 May 2021
Topic Review
High Performance Liquid Chromatography with Fluorescence Detection Methods
Steroids are compounds widely available in nature and synthesized for therapeutic and medical purposes. Although several analytical techniques are available for the quantification of steroids, their analysis is challenging due to their low levels and complex matrices of the samples. The efficiency and quick separation of the high performance liquid chromatography (HPLC) combined with the sensitivity, selectivity, simplicity, and cost-efficiency of fluorescence, make HPLC coupled to fluorescence detection (HPLC-FLD) an ideal tool for routine measurement and detection of steroids.
  • 2.1K
  • 01 Aug 2022
Topic Review
Alkylimidazoles
Alkylimidazoles have good complexing properties, also they are  cheap so can be successfully used in the separation of metal ions from aqueous solutions.
  • 2.1K
  • 16 Dec 2020
Topic Review
Seaweed Polysaccharide Based Products/Materials
Among the various natural polymers, polysaccharides are one of the oldest biopolymers present on the earth. They play a very crucial role in the survival of both animals and plants. Due to the presence of hydroxyl functional groups in most of the polysaccharides, it is easy to prepare their chemical derivatives. Several polysaccharide derivatives are widely used in a number of industrial applications. The polysaccharides such as cellulose, starch, chitosan, etc. have several industrial applications but due to some distinguished characteristic properties, seaweed polysaccharides are preferred in a number of applications.
  • 2.0K
  • 17 Sep 2021
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