Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Black Soldier Fly
The black soldier fly (BSF), Hermetia illucens Linnaeus, is a large Stratiomyidae fly (13-20 mm in size) found worldwide, but it is believed to have originated in the Americas. It is frequently found in the tropics and temperate regions throughout the world. Although adapted primarily to these regions, it can tolerate wide extremes of temperature except when ovipositing. They are considered beneficial insects and non-pests. The adult fly does not have mouthparts, stingers, or digestive organs; thus, they do not bite or sting and do not feed during its short lifespan. They feed only as larvae and are, therefore, not associated with disease transmission. BSF larvae (BSFL) are voracious eaters of a wide range of organic wastes, decomposing and returning nutrients to the soil. Additionally, BSFL is an alternative protein source for aquaculture, pet food, livestock feed, and human nutrition.
  • 42.1K
  • 25 Apr 2023
Topic Review
Lignosulfonates
Lignosulfonates are biobased surfactants and specialty chemicals, which are usually produced as a byproduct during sulfite pulping of wood. They are the technical lignin that is, by far, the most commercially traded and are hence vital for replacing non‑renewable and fossil‑based chemicals. Due to their prominent use as plasticizers, dispersants, and stabilizers, the physicochemical properties of lignosulfonates play a key role in determining their end‑use and performance. Their chemical composition and structure are inherently linked to the characteristic behavior of lignosulfonates. This entry hence outlines the fundamental chemistry of lignosulfonates, while discussing the following physicochemical properties: · Solubility in different solvents · Conformation and shape in aqueous solution · Self-association and agglomeration in aqueous solution · Precipitation · Adsorption at surfaces and interfaces
  • 8.5K
  • 05 Jan 2021
Topic Review
Carbon Anode
Carbon anode refers to a broad family of essentially pure carbon, whose members can be tailored to vary widely in their strength, density, conductivity, pore structure, and crystalline development. These attributes contribute to their widespread applicability. Specific characteristics are imparted to the finished product by controlling the selection of precursor materials (including cokes, polymers and fibers) and the method of processing. In general, carbon anode electrodes are characterized by low cost production, high surface area, a wide working potential window in many media, high electrocatalytic activities for different redox-active chemical and biochemical systems, and chemical inertness.Moreover, their surface chemistry enables the functionalization of these carbon platforms via strong covalent or noncovalent methods with surface modifiers, which improves their electrochemical performance. Recent achievements of carbon anode materials and their structural design for better performances of aluminium production, lithium-ion secondary batteries, lithium cobalt oxide batteries, nano-tube production, substitution of amorphous electrode materials, photoanodes production, solar cells, fuel cells, supercapacitors, sensors and pumps, neurochemical monitors, etc., are finding enormous applications in industrial, commercial and social sectors. 
  • 5.7K
  • 31 Aug 2021
Topic Review
Photocatalysts
Photocatalysts indicates the acceleration of a chemical reaction occurring on the surface of a semiconductor material (the catalyst) caused by the presence of light. Illumination of the catalyst causes the generation of free changes (electrons and holes) that can partecipate to chemical reactions, thus causing (or acceleratin) them. Photocatalysis con be used in hydrogen (H2) production (e.g., via water splitting or photo-reforming of organic substrates), CO2 reduction, pollution mitigation and water or air remediation via oxidation (photodegradation) of pollutants. Titanium dioxide (TiO2) is a “benchmark” photocatalyst, thanks to many favorable characteristics.
  • 5.4K
  • 26 May 2021
Topic Review
Copper(II) Complex
A dinuclear copper(II) complex of (1) (where bipy = 2,2′‑bipyridine, bzt = benzoate and ox = oxalate) was synthesised and characterised by diffractometric (powder and single-crystal XRD) and thermogravimetric (TG/DTG) analyses, spectroscopic techniques (IR, Raman, electron paramagnetic resonance spectroscopy (EPR) and electronic spectroscopy), magnetic measurements and density functional theory (DFT) calculations. The analysis of the crystal structure revealed that the oxalate ligand is in bis(bidentate) coordination mode between two copper(II) centres. The other four positions of the coordination environment of the copper(II) ion are occupied by one water molecule, a bidentate bipy and a monodentate bzt ligand. An inversion centre located on the ox ligand generates the other half of the dinuclear complex. Intermolecular hydrogen bonds and pi-pi for the organisation of the molecules in the solid state. Molar magnetic susceptibility and field dependence magnetisation studies evidenced a weak intramolecular–ferromagnetic interaction (J = +2.9 cm‑1) between the metal ions. The sign and magnitude of the calculated J value by density functional theory (DFT) are in agreement with the experimental data.
  • 5.3K
  • 30 Oct 2020
Topic Review
One-Dimensional (1D) Nanostructured Materials
At present, the world is at the peak of production of traditional fossil fuels. Much of the resources that humanity has been consuming (oil, coal, and natural gas) are coming to an end. The human being faces a future that must necessarily go through a paradigm shift, which includes a progressive movement towards increasingly less polluting and energetically viable resources. In this sense, nanotechnology has a transcendental role in this change. For decades, new materials capable of being used in energy processes have been synthesized, which undoubtedly will be the cornerstone of the future development of the planet.
  • 4.8K
  • 23 Jun 2021
Topic Review
Polylactic Acid
As a degradable and environmentally friendly polymer, polylactic acid, also known as polylactide, is favored by researchers and has been used as a commercial material in various studies. Lactic acid, as a synthetic raw material of polylactic acid, can only be obtained by sugar fermentation. Good biocompatibility and biodegradability have led it to be approved by the U.S. Food and Drug Administration (FDA) as a biomedical material. Polylactic acid has good physical properties, and its modification can optimize its properties to a certain extent. Polylactic acid blocks and blends play significant roles in drug delivery, implants, and tissue engineering to great effect.  This entry introduces synthesis and biological application of polylactic acid.
  • 4.6K
  • 17 Nov 2020
Topic Review
Fundamentals of Oxygen Reduction Reaction
Oxygen reduction reaction (ORR) has been the subject of huge investigation since it is at the heart of various energy conversion and storage systems such as fuel cells, metal-air batteries, and so on. The mechanistic pathway is governed not only by the oxygen adsorption mode, but it also depends on the dissociation barrier of the catalyst surface. 
  • 4.5K
  • 02 Sep 2022
Topic Review
Tetrabutylammonium Bromide
During the last two decades, tetrabutylammonium bromide (TBAB) has gained significant attention as an efficient metal-free homogeneous phase-transfer catalyst. A catalytic amount of TBAB is sufficient to catalyze various alkylation, oxidation, reduction, and esterification processes. It is also employed as an efficient co-catalyst for numerous coupling reactions. It has also acted as an efficient zwitterionic solvent in many organic transformations under molten conditions.
  • 4.5K
  • 09 Feb 2021
Topic Review
Dyes, Minerals, and Vitamins Used in Cosmetics
Most minerals and vitamins are beneficial when it comes to the improvement of the condition of the skin, hair or nails, and as they are mostly safe for use, they are valued raw materials and cosmetic ingredients. Dyes and pigments, due to the potential negative impact on human health of many of them, are often controversial components of cosmetic preparations. The constantly growing awareness of consumers makes cosmetics manufacturers strive to eliminate potentially harmful substances and use safe raw materials and ingredients of natural origin.
  • 4.5K
  • 23 Nov 2021
Topic Review
Acoustic Extinguishing
In the fire-extinguishing process, in principle, one of the components in the fire tetrahedron must be removed. For example, a natural gas fire occurring on a stovetop burner can be extinguished in various ways: Eliminating the fuel source by shutting off the gas supply may be the first option. Another option is to completely cover the flame to block any oxidizer that is present, such as oxygen in the air, during combustion.
  • 4.1K
  • 25 Mar 2022
Topic Review
Aminoacid Surfactants
Aminoacid surfactants are a type of surfactant that is composed of both an amino acid and a hydrophobic tail. They have both hydrophilic and hydrophobic properties, which allows them to lower the surface tension between two immiscible phases, such as oil and water. Aminoacid surfactants are becoming increasingly popular in personal care and cosmetic products due to their mildness and biocompatibility. They are often used as alternatives to traditional surfactants, which can be harsh and irritating to the skin and eyes. Here are several types of amino acid surfactants, each with its own unique properties and applications. Alkyl-L-glutamate, alkyl-L-amino acids, alkyl-D-amino acids, alkyl-amino acids, and dipeptide surfactants are just a few examples of the different types of amino acid surfactants available. With their biodegradability, low toxicity, and excellent foaming and emulsifying properties, amino acid surfactants are a valuable addition to the surfactant industry.
  • 4.0K
  • 24 Mar 2023
Topic Review
Carbon Dots: Synthesis and Properties
Carbon dots (CDs) are zero-dimensional optically active carbon-based nanomaterials with a size of less than 10 nm. The material property of the CD is largely linked to the various bottom-up & top-down synthesis approaches, including surface passivation and functionalization, and the carbon precursors. The CDs can be engineered to enhance the chemical and physical functional properties by doping with heteroatom such as nitrogen, phosphorus, sulfur, fluorine, and boron. Because of its various advantageous properties, CDs are utilized in the field of chemical/biological sensing, bioimaging, and drug delivery. These nanosized CDs can change their light emission properties in response to various external stimuli such as pH, temperature, pressure, and light. The CD’s remarkable stimuli-responsive smart material properties have recently stimulated massive research interest for their exploitation to develop various sensor platforms. 
  • 4.0K
  • 16 Mar 2021
Topic Review
Molybdenum Disulfide
Molybdenum disulfide (MoS2) is one of the compounds discussed nowadays due to its outstanding properties that allowed its usage in different applications. Its band gap and its distinctive structure make it a promising material to substitute graphene and other semiconductor devices. It has different applications in electronics especially sensors like optical sensors, biosensors, electrochemical biosensors that play an important role in the detection of various diseases’ like cancer and Alzheimer. It has a wide range of energy applications in batteries, solar cells, microwave, and Terahertz applications. It is a promising material on a nanoscale level, with favorable characteristics in spintronics and magnetoresistance. 
  • 3.7K
  • 24 May 2021
Topic Review
Resistive Gas Sensor
With a series of widespread applications, resistive gas sensors are considered to be promising candidates for gas detection, benefiting from their small size, ease-of-fabrication, low power consumption and outstanding maintenance properties. One-dimensional (1-D) nanomaterials, which have large specific surface areas, abundant exposed active sites and high length-to-diameter ratios, enable fast charge transfers and gas-sensitive reactions. They can also significantly enhance the sensitivity and response speed of resistive gas sensors.
  • 3.5K
  • 17 Aug 2021
Topic Review
Binders Used for the Manufacturing of Composite Materials
Binders, or tackifiers, have become widespread in the production of new composite materials by liquid composite molding (LCM) techniques due to their ability to stabilize preforms during laying-up and impregnation, as well as to improve fracture toughness of the obtained composites, which is very important in aviation, automotive, ship manufacturing, etc. Furthermore, they can be used in modern methods of automatic laying of dry fibers into preforms, which significantly reduces the labor cost of the manufacturing process.
  • 3.4K
  • 19 Jan 2022
Topic Review
Applications of Liquid Crystals-Based Sensors
Liquid crystals are a class of chemical substances that exist in intermediate states between crystalline solids and liquids. They thus share the anisotropic properties of crystalline solids as well as fluid properties of isotropic liquids. 
  • 3.3K
  • 23 Mar 2022
Topic Review
Reverse Water Gas Shift Reaction
The catalytic conversion of CO2 to CO by the reverse water gas shift (RWGS) reaction followed by well-established synthesis gas conversion technologies could be a practical technique to convert CO2 to valuable chemicals and fuels in industrial settings. For catalyst developers, prevention of side reactions like methanation, low-temperature activity, and selectivity enhancements for the RWGS reaction are crucial concerns. Cerium oxide (ceria, CeO2) has received considerable attention due to its exceptional physical and chemical properties. 
  • 3.2K
  • 09 Oct 2022
Topic Review
Spirulina for Skin Care
Spirulina stands out as a sustainable bioactive microalga with health-promoting properties, and an important active ingredient of natural cosmetics products. 
  • 3.1K
  • 05 Feb 2021
Topic Review
Sugar Based Surfactants
Sugar-based surfactants are a class of surfactants derived from natural sugars, such as glucose, sucrose, and maltose. These surfactants have gained significant interest in recent years due to their biodegradability, low toxicity, and high compatibility with biological systems. Sugar-based surfactants are classified into two main groups: alkyl polyglucosides (APGs) and saccharide fatty acid esters (SFAEs). APGs are produced by reacting a fatty alcohol with glucose, while SFAEs are produced by esterifying a sugar molecule with a fatty acid. APGs have excellent cleaning and foaming properties and are used in a variety of personal care and household products, including shampoos, body washes, and dishwashing detergents. SFAEs are mainly used in the food industry as emulsifiers and stabilizers. One of the main advantages of sugar-based surfactants is their biodegradability, which means that they break down into harmless substances when exposed to environmental conditions such as sunlight, water, and microorganisms. This makes them an attractive alternative to synthetic surfactants, which can persist in the environment for a long time and have negative impacts on ecosystems.
  • 3.0K
  • 24 Mar 2023
  • Page
  • of
  • 15
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
ScholarVision Creations
Feedback