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Topic Review
The Recent Progress on Silver Nanoparticles
Nanomaterials are highly effective,  environmentally friendly, and applicable for various applications. Recently, silver nanoparticles (Ag NPs) are increasingly being synthesized due to their physical, chemical, and biomedical properties. Silver nanoparticles can be synthesized using physical, chemical, and biological methods. Ag NPs are widely applied in electronic and sensing applications.
  • 937
  • 20 Nov 2021
Topic Review
Pt-Based Catalysts in Proton Exchange Membrane Fuel Cells
Proton exchange membrane fuel cells (PEMFCs) have attracted extensive attention because of their high efficiency, environmental friendliness, and lack of noise pollution. However, PEMFCs still face many difficulties in practical application, such as insufficient power density, high cost, and poor durability. The main reason for these difficulties is the slow oxygen reduction reaction (ORR) on the cathode due to the insufficient stability and catalytic activity of the catalyst. It is very important to develop advanced platinum (Pt)-based catalysts to realize low Pt loads and long-term operation of membrane electrode assembly (MEA) modules to improve the performance of PEMFC. By designing the structure of a Pt-based catalyst, it can be generated on a special surface structure, so as to boost the stability and activity of Pt-based catalysts, such as low-dimensional nanostructures (e.g., two-dimensional nanoplates and one-dimensional nanowires). These structures not only have high conductivity, but can also make sure the nanocrystals are fully in contact with the support and effectively inhibit Ostwald ripening, with excellent stability.
  • 937
  • 17 Feb 2023
Topic Review Video
Physicochemical Processes Leading to Plasma-Driven Solution Electrolysis
A new type of electrolysis, initially known as the contact glow-discharge electrolysis (CGDE) and, more recently, as the plasma-driven solution electrolysis (PDSE), has attracted attention as an alternative method of hydrogen production. PDSE is a nontypical electrochemical process in which electric plasma is formed in the glow discharges excited by the direct or pulsed current in a gas–vapor envelope in the vicinity of the discharge electrode immersed in the electrolytic solution. The yield of chemicals in PDSE (i.e., the ratio of the moles of the product formed to the moles of electrons consumed in a chemical reaction) is several times higher than the Faradaic production of chemicals (predicted by Faraday’s law). In PDSE, new chemical compounds can also be synthesized, which does not happen using Faradaic electrolysis.
  • 936
  • 31 Oct 2022
Topic Review
Deep Eutectic Solvents for Biomass-Based Waste Valorization
Biomass waste streams are potential feedstocks for a variety of products such as fuels, polymers, and building blocks. The deep eutectic solvents (DESs), eutectic mixtures of Lewis (or Brønsted) acids and bases with incomplete proton transfer, were intentionally designed by choosing two or more distinct components that could interact via hydrogen bonding. The DESs, often with non-stoichiometric ratios between components, present melting points significantly lower than the starting materials and produce mixtures of charged and neutral species. 
  • 936
  • 14 Oct 2022
Topic Review
Electrospinning Process of Electrospun Fibers
Electrospinning is a simple and versatile method to generate nanofibers. Remarkable progress has been made in the development of the electrospinning process. The production of nanofibers is affected by many parameters, which influence the final material properties. Electrospun fibers have a wide range of applications, such as energy storage devices and biomedical scaffolds.
  • 935
  • 24 Aug 2023
Topic Review
Ignition of Fires from Electrical Causes
In a number of countries, somewhere around 20% of reported building fires are due to electrical faults or failures. There can be a number of mechanisms responsible, but arcing in air and hot-surface ignitions of combustible materials are important causes. Details of these two mechanisms are reviewed. It is shown that even though arcing in air produces temperatures greatly higher than the ignition temperature of any ignitable solid, this does not always result in ignition. With regards to ignitions from hot surfaces or objects, it is shown that the area of the hot object presented to the ignitable material is a crucial variable.
  • 935
  • 10 Aug 2023
Topic Review
Sensors Used in Water Monitoring
Water monitoring sensors in industrial, municipal and environmental monitoring are advancing our understanding of science, aid developments in process automatization and control and support real-time decisions in emergency situations. Sensors are becoming smaller, smarter, increasingly specialized and diversified and cheaper. Advanced deployment platforms now exist to support various monitoring needs together with state-of-the-art power and communication capabilities. For a large percentage of submerged instrumentation, biofouling is the single biggest factor affecting the operation, maintenance and data quality. This increases the cost of ownership to the extent that it is prohibitive to maintain operational sensor networks and infrastructures. In this context, the paper provides a brief overview of biofouling, including the development and properties of biofilms. The state-of-the-art established and emerging antifouling strategies are reviewed and discussed. 
  • 935
  • 24 Feb 2021
Topic Review
Adsorption of Pesticides onto Clay Minerals
Adsorption of pesticides onto natural clay mineral relies on the use of adsorbents with minimal treatment beyond their preparation to provide a narrow size distribution and homoionic form by exchanging the naturally occurring interlamellar cations (in the case of smectites) by some alkaline (Na+ or K+) or alkaline earth (Ca2+or Mg2+) cation. Additional modifications include organophilization, intercalation with metal polycations and pillaring.  The adsorption capacity and strength of pesticides onto homoionic, organophilic and intercalated/pillared clay minerals depend on the chemical nature of the pesticide, surface area, and pore volume. Electrostatic interactions, hydrogen and coordinative bonds, surface complexations, and hydrophobic associations are the main interactions between pesticides and clay minerals.
  • 934
  • 29 Nov 2021
Topic Review
Coconut Palm
The price of traditional sources of nutrients used in animal feed rations is increasing steeply in developed countries due to their scarcity, high demand from humans for the same food items, and expensive costs of raw materials. Thus, one of the alternative sources is coconut parts or coconut as a whole fruit. Coconut is known as the ‘tree of abundance’, ‘tree of heaven’, and ‘tree of life’ owing to its numerous uses, becoming a very important tree in tropical areas for its provision of food, employment, and business opportunities to millions of people. Coconut contains a rich profile of macro and micronutrients that vary depending on the parts and how they are used. It is frequently chosen as an alternative source of protein and fiber. Its uses as an antibacterial agent, immunomodulant, and antioxidant further increase its importance. Using coconut oil in ruminant feed helps to minimize methane gas emissions by 18–30%, and to reduce dry matter intake up to 4.2 kg/d. The aquaculture sectors also use coconut palm as an alternative source because it significantly improves the digestion, growth, lipid metabolism, health, and antioxidative responses. However, coconut is not widely used in poultry diets although it has adequate amount of protein and carbohydrate due to anti-nutritional factors such cellulose (13%), galactomannan (61%), and mannan (26%). 
  • 933
  • 31 Aug 2022
Topic Review
Β-lactam Antibiotic
β-lactam antibiotics (beta-lactam antibiotics) are antibiotics that contain a beta-lactam ring in their molecular structure. This includes penicillin derivatives (penams), cephalosporins and cephamycins (cephems), monobactams, carbapenems and carbacephems. Most β-lactam antibiotics work by inhibiting cell wall biosynthesis in the bacterial organism and are the most widely used group of antibiotics. Until 2003, when measured by sales, more than half of all commercially available antibiotics in use were β-lactam compounds. The first β-lactam antibiotic discovered, penicillin, was isolated from a rare variant of Penicillium notatum (since renamed Penicillium chrysogenum). Bacteria often develop resistance to β-lactam antibiotics by synthesizing a β-lactamase, an enzyme that attacks the β-lactam ring. To overcome this resistance, β-lactam antibiotics can be given with β-lactamase inhibitors such as clavulanic acid.
  • 933
  • 24 Nov 2022
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