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Topic Review
Ceramic-Polymer Composite Membranes
Ceramics and polymers are two main candidate materials for membranes, where the majority has been made of polymeric materials, due to the low cost, easy processing, and tunability in pore configurations. In contrast, ceramic membranes have much better performance, extra-long service life, mechanical robustness, and high thermal and chemical stabilities, and they have also been applied in gas, petrochemical, food-beverage, and pharmaceutical industries, where most of polymeric membranes cannot perform properly. 
  • 1.5K
  • 22 Jun 2021
Topic Review
XPS Analysis of Carbon Materials
The surface chemistry of carbon materials is predominantly explored using x-ray photoelectron spectroscopy (XPS). However, many journal articles have critical failures in the published analysis which typically stems from an ill-informed approach to analyzing the spectroscopic data. The presented work presents a discussion on lineshapes and associated changes in the spectral envelope of predominantly graphitic materials, which together with the use of the D-parameter to verify levels of the graphitic content, using this information to highlight a simple and logical approach to strengthen confidence in the functionalization derived from the carbon core-level spectra.
  • 1.5K
  • 16 Jul 2021
Topic Review
Applications of Zinc Oxide Nanoparticles in Food/Agriculture
Zinc oxide nanoparticles (ZnO-NPs) have gained significant interest in the agricultural and food industry as a means of killing or reducing the activity of microorganisms. The antibacterial properties of ZnO-NPs may improve food quality, which has a direct impact on human health. ZnO-NPs are one of the most investigated inorganic nanoparticles and have been used in various related sectors, with the potential to rapidly gain attention and increase interest in the agriculture and food industries. 
  • 1.5K
  • 20 Apr 2023
Topic Review
Small Molecules for Corneal Neovascularization
Multiple natural-source and synthetic small molecules have been tested preclinical for treating corneal neovascularization. Such small molecules include synthetic inhibitors of the vascular endothelial growth factor (VEGF) receptor and other tyrosine kinases, plus repurposed antimicrobials, as well as natural source-derived flavonoid and non-flavonoid phytochemicals, immunosuppressants, vitamins, and histone deacetylase inhibitors.
  • 1.5K
  • 17 Aug 2020
Topic Review
Cellulose and Cellulose Derivatives
Among the biomaterials, cellulose is the most abundant, cheap, sustainable, chemical reactive and modifiable natural macromolecular compound on the Earth. It is a carbohydrate homopolymer, which is composed of repeating long linear chains of β-anhydro-D-glucopyranose units, linked together by an ether bond between -OH group of C4, and the C1 carbon atom, via a β-1,4-glycosidic bond.
  • 1.5K
  • 10 Feb 2023
Topic Review
Heterocyclic Anticancer Compounds
Heterocyclic organic compounds are designated as integral components on a wide array of structures with both pharmacological and biological importance. They constitute a large cohort of structures with immense importance in the life sciences. 
  • 1.5K
  • 29 Mar 2022
Topic Review
N-Type Organic Semiconductors
This work was intended to enlarge the gates toward green organic technologies at room temperature, searching for new types of semiconductors with low toxicity and simple molecular organization. In our previous studies, para-aminobenzoic acid was used to construct a p-type green semiconductor. A non-toxic organic compound, acting as an electron donor, is sulpho-salicylic acid. SSA can be efficiently attached to the external shell of a ferrite (Fe3O4) nanocore, providing Fe3O4–SSA nanoparticles. This is a N-Type Organic Semiconductor - made by green technologies and used to construct a simple thin film transistor. 
  • 1.5K
  • 22 Oct 2020
Topic Review
Compounds of Zinc
Compounds of zinc are chemical compounds containing the element zinc which is a member of the group 12 of the periodic table. The oxidation state of most compounds is the group oxidation state of +2. Zinc may be classified as a post-transition main group element with zinc(II). Zinc compounds are noteworthy for their nondescript behavior, they are generally colorless (unlike other elements with the oxidation number +2, which are usually white), do not readily engage in redox reactions, and generally adopt symmetrical structures.
  • 1.5K
  • 25 Nov 2022
Topic Review
Base
In chemistry, there are three definitions in common use of the word base, known as Arrhenius bases, Brønsted bases, and Lewis bases. All definitions agree that bases are substances which react with acids as originally proposed by G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form Hydroxide ions OH−. These ions can react with hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction. A base was therefore a metal hydroxide such as NaOH or Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. They are slippery to the touch, can taste bitter and change the color of pH indicators (e.g., turn red litmus paper blue). In water, by altering the autoionization equilibrium, bases yield solutions in which the hydrogen ion activity is lower than it is in pure water, i.e., the water has a pH higher than 7.0 at standard conditions. A soluble base is called an alkali if it contains and releases OH− ions quantitatively. Metal oxides, hydroxides, and especially alkoxides are basic, and conjugate bases of weak acids are weak bases. Bases and acids are seen as chemical opposites because the effect of an acid is to increase the hydronium (H3O+) concentration in water, whereas bases reduce this concentration. A reaction between aqueous solutions of an acid and a base is called neutralization, producing a solution of water and a salt in which the salt separates into its component ions. If the aqueous solution is saturated with a given salt solute, any additional such salt precipitates out of the solution. In the more general Brønsted–Lowry acid–base theory (1923), a base is a substance that can accept hydrogen cations (H+)—otherwise known as protons. This does include aqueous hydroxides since OH− does react with H+ to form water, so that Arrhenius bases are a subset of Brønsted bases. However, there are also other Brønsted bases which accept protons, such as aqueous solutions of ammonia (NH3) or its organic derivatives (amines). These bases do not contain a hydroxide ion but nevertheless react with water, resulting in an increase in the concentration of hydroxide ion. Also, some non-aqueous solvents contain Brønsted bases which react with solvated protons. For example in liquid ammonia, NH2− is the basic ion species which accepts protons from NH4+, the acidic species in this solvent. G. N. Lewis realized that water, ammonia, and other bases can form a bond with a proton due to the unshared pair of electrons that the bases possess. In the Lewis theory, a base is an electron pair donor which can share a pair of electrons with an electron acceptor which is described as a Lewis acid. The Lewis theory is more general than the Brønsted model because the Lewis acid is not necessarily a proton, but can be another molecule (or ion) with a vacant low-lying orbital which can accept a pair of electrons. One notable example is boron trifluoride (BF3). Some other definitions of both bases and acids have been proposed in the past, but are not commonly used today.
  • 1.5K
  • 29 Sep 2022
Topic Review
Medical Applications of Hybrid Hydrogels Containing Natural Polymers
Hybrid hydrogels definition is still debatable. They are defined either as a complex composed  chemically or physically cross-linking structures, or it refers to systems combining different polymers and/or with nanoparticles, such as plasmonic, magnetic, and carbonaceous nanoparticles, among others, or they are constituted by chemically, functionally, and morphologically distinct features from at least two different classes of molecules, which can include biologically active polymers as polysaccharides and/or proteins, peptides, or nano/microstructures, interconnected via physical or chemical means.
  • 1.5K
  • 29 Mar 2022
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