Electrostatics

Ionic Bonding It is a chemical bond that bonds a metal to a non-metal by means of electrostatic attraction between the ions. They have high melting points and are strong. It is also known as electrovalent bond. An ionic compound is formed from a metallic cation and a non-metallic anion. They are held by opposite charges and the bond is formed…

5. Protein purification There are many thousand kinds of proteins with different properties and functions in a cell. Proteins have been purified in active form on the basis of such characteristics as solubility, size, charge and specific binding affinity. Normally, protein mixtures are subjected to a series of separations, each based on a different property to yield a pure protein. 5.1 Separation based on solubility (Scopes, 1994) The protein solubility in various solvents depended on the…

4.1.1 Particulate control. Particulate can be defined or referred to as tiny particles of matter like dust, smoke, soot which are being emitted during agricultural and industrial processes as well as other economic activities. Various methods involved with particulate control operate basic principles. Solid particulate particles are usually isolated from gases where they are controlled by physical procedures like through a settling chamber. Settling chamber is a wide and elongated pipe where…

1762-IF4 is an Allen Bradley MicroLogix 1200 System with 4 Channel Current/Voltage Analog Input Module. It has a dimension of 90 x 87 x 40.4 mm. It has Delta-Sigma converter and 4 differential (bipolar) inputs. It’s analog operating voltage range is -10 – 10 V DC normal and -10.5 – 10.5 V DC full scale. It’s analog operating current range is 4 – 20 mA normal and -21 – 21 mA full scale. It converts the analog input up to the full-scale range. It enhances the functionality of MicroLogix 1200…

Field based QSAR is a tool for modeling the relationship between the known actives and the unknowns. The 3D characteristics of the compounds are matched with the known actives for activity prediction. 3D QSAR models are based on fields, such as electrostatic, hydrophobic or steric fields for a set of aligned ligands. The reference standards were divided into a training set comprising of 38 compounds and a test set having 17 compounds. The scatter diagram showing the predicted activity of the…

Salts and molecules have similar characteristics, and many differences whether we can tell by first looks or not. Testing these two only supports the differences, and many structural functions cause these differences. Since salts are ionically bonded, they have different properties and functions compared to the covalent bonded molecules. Salts have a ionic bond, and we can confirm due to their electronegativity. As you move from left to right on the periodic table you would notice that…

Sodium alginate (SA) is a natural anionic polysaccharide obtained from sea weeds. It contains β-D-mannuronate (M) and α-L-glucuronate (G) residues linked by (1-4)- glycosidic linkages (Fig. 7.1) and arranged in homopolymeric blocks of each type and in heteropolymeric blocks [1]. It is a water soluble polysaccharide and has pKa values of 3.38 for the ‘M’ and 3.65 for ‘G’ units [2]. It can form complexes with positively charged polymers due to its anionic character. It is utilized as emulsifier,…

Chitin is a linear polysaccharide, with β-(1-4)-linked N-acetyl-D-glucosamine. Found in the exoskeletons of crustaceans (crab, shrimp, lobster, insects) & molluscs, as well as the cell walls of algae and fungi, chitin is the second-most naturally abundant polysaccharide after cellulose [1, 2]. Chitin occurs naturally in the polymorphic forms: α, β and γ. The α-polymorphic form of chitin is the most abundant in nature, present in the strong exoskeleton of crustaceans [6]. α-Chitin forms tightly…

covalent bond has electrostatic forces of attraction between shared pairs of electrons, another example is of a giant covalent bond. A giant covalent bond is held in a giant molecular lattice structure. (See diagram B below.) B) s-cool (2016) This giant structure is made of strong covalent bonds, so to break these bonds it takes a lot of energy,(OCR 2008) this results in the melting and boiling points of a giant covalent bond being extremely high to overcome the strong electrostatic force…

Most antimicrobial peptides contain well-defined cationic domains and display a net positive charge ranging from +2 to +9. Cationicity is important as it influences the degree of electrostatic attraction of antimicrobial peptides towards negatively charged phospholipid membranes of bacteria and other microorganisms. Consequently, the polycationic AMPs are selectively attracted to the negatively charged bacterial targets but not to the…