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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.
  • 2.9K
  • 24 Mar 2023
Topic Review
Starch-Based Biodegradable Films for Food Packaging
The use of biodegradable packaging material as an alternative to conventional petrochemical-based polymers is based on the environmental issues associated with conventional materials. Starch-based biodegradable films can be applied in food packaging. It was evident that starch stands out among biopolymers due to its abundance and cost effectiveness.
  • 2.9K
  • 07 Apr 2022
Topic Review
Chloramine
Chloramines are derivatives of ammonia by substitution of one, two or three hydrogen atoms with chlorine atoms: monochloramine (chloroamine, NH2Cl), dichloramine (NHCl2), and nitrogen trichloride (NCl3). The term chloramine also refers to a family of organic compounds with the formulas R2NCl and RNCl2 (where R is an organic group). Monochloramine (chloramine) is an inorganic compound with the formula NH2Cl. It is an unstable colorless liquid at its melting point of −66 °C (−87 °F), but it is usually handled as a dilute aqueous solution, in which form it is sometimes used as a disinfectant. Chloramine is too unstable to have its boiling point measured. It is listed as a tumorigen and mutagen. The wholesale cost in the developing world is about 13.80 to 18.41 U.S. dollars per 500 grams.
  • 2.9K
  • 16 Nov 2022
Topic Review
Copper-Based Conductive Inks
Silver (Ag), gold (Au), and copper (Cu) have been utilized as metals for fabricating metal-based inks/pastes for printed/flexible electronics. Among them, Cu is the most promising candidate for metal-based inks/pastes. Cu has high intrinsic electrical/thermal conductivity, which is more cost-effective and abundant, as compared to Ag. Moreover, the migration tendency of Cu is less than that of Ag. Thus, recently, Cu-based inks/pastes have gained increasing attention as conductive inks/pastes for printed/flexible electronics. We can divide Cu-based inks/pastes into four categories from the viewpoints of Cu sources: (i) traditional micron-sized flake/powder type, (ii) nanoparticle type, (iii) nanowire type, and (iv) precursor ion type. However, the disadvantages of Cu-based inks/pastes are their instability against oxidation under an ambient condition and tendency to form insulating layers of Cu oxide, such as cuprous oxide (Cu2O) and cupric oxide (CuO). The formation of the Cu oxidation causes a low conductivity in sintered Cu films and interferes with the sintering of Cu particles. The surface and interface designs for Cu-based conductive inks/pastes are important strategies for the oxidation resistance of Cu and low-temperature sintering to produce highly conductive Cu patterns/electrodes on flexible substrates. The surface control approaches include surface designs by polymers, small ligands, core-shell structures, and surface activation. The Cu-based mixed inks/pastes offer improved performances compared with the single use of each component.
  • 2.9K
  • 07 Sep 2020
Topic Review
Advantages and Disadvantages of Covalent Inhibitors
The formation of covalent bonds that target proteins can offer drugs diverse advantages in terms of target selectivity, drug resistance, and administration concentration. The most important factor for covalent inhibitors is the electrophile (warhead), which dictates selectivity, reactivity, and the type of protein binding (i.e., reversible or irreversible) and can be modified/optimized through rational designs. Furthermore, covalent inhibitors are becoming more and more common in proteolysis, targeting chimeras (PROTACs) for degrading proteins, including those that are currently considered to be ‘undruggable’.
  • 2.9K
  • 10 May 2023
Topic Review
Natural Polymers Used in Edible Food Packaging
Natural polymers like polysaccharides and proteins, i.e., alginate; carrageenan; chitosan; starch; pea protein, are important materials obtained from renewable plant, algae and animal sources, as well as from agroindustrial residues. Historically, some of them have been widely used by ancient populations for food packaging until these were replaced by petroleum-based plastic materials after World War II. Nowadays, biobased materials for food packaging have attracted attention. Their use was boosted especially because of the environmental pollution caused by inappropriate disposal of plastic packaging. Biobased materials are welcome to the design of food packaging because they possess many advantages, such as biodegradability, biocompatibility and low toxicity. Depending on the formulation, certain biopolymer-based packaging may present good barrier properties, antimicrobial and antioxidant activities Thus, polysaccharides and proteins can be combined to form diverse composite films with improved mechanical and biological behaviors, making them suitable for packaging of different food products. 
  • 2.9K
  • 10 Jan 2022
Topic Review
Polyphenols against Skin Aging
Polyphenols représente a superfamily of diverse naturally occurring phytochemicals, which exert a particularly potent antioxidant activity, thereby contributing to delay skin aging.
  • 2.9K
  • 19 Nov 2020
Topic Review
Unbibium
Unbibium /uːnˈbɪbiəm/, also known as eka-thorium or simply element 122, is the currently hypothetical chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol respectively, until a permanent name is decided upon. In the periodic table of the elements, it is expected to follow unbiunium as the second element of the superactinides, or the g-block and the fourth element of the 8th period. It has attracted recent attention, for similarly to unbiunium, it is expected to fall within the range of the island of stability. Despite many attempts, unbibium has not yet been synthesized, and therefore no natural isotopes have been found to exist. It is currently predicted that it has a g-orbital, the second element of which to have such besides unbiunium, which also has yet to be synthesized. It will most likely require nuclear fission to be produced artificially. In 2008, it was claimed to have been discovered in natural thorium samples but that claim has now been dismissed by recent repetitions of the experiment using more accurate techniques.
  • 2.9K
  • 29 Nov 2022
Topic Review
Seaweeds in Producing Safe and Sustainable Bio-Packaging
Diverse studies demonstrate that seaweed polysaccharides (e.g., alginates and carrageenans) not only provide health benefits, but also contribute to the production of biopolymeric film and biodegradable packaging. The dispersion of plastics and microplastics in the oceans provoke serious environmental issues that influence ecosystems and aquatic organisms. Thus, the sustainable use of seaweed-derived biopolymers is now crucial to replace plasticizers with biodegradable materials, and thus preserve the environment. 
  • 2.9K
  • 24 Mar 2022
Topic Review
Solketal
Solketal (CAS 100–79–8) has low viscosity at room temperature (~11 cP) and freezing, boiling, and flash points of about −26 °C, 190 °C, and 80 °C, respectively. The density is 1.06 g/cm3 and the vapor pressure is 107.32 mmHg. It has low toxicity, slight odor, and it is non-irritant for humans; due to these characteristics and to the renewable origin, it is considered an environmentally friendly substance. It is completely miscible in water and in most organic compounds, which endows its solvent capacity.
  • 2.9K
  • 07 May 2021
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