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Symbols, Terminology, and Nomenclature
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Osmotic coefficient () - Defined by = ln aA/(MAmB), where MA is the molar mass of substance A (normally the solvent), aA is its activity, and the mB are molalities of the solutes. [1] Osmotic pressure () - The excess pressure necessary to maintain osmotic equilibrium between a solution and the pure solvent separated by a membrane permeable only to the solvent. In an ideal dilute solution = cBRT , where cB is the amountof-substance concentration of the solute, R is the molar gas constant, and T the temperature. [1,2] Ostwald dilution law - A relation for the concentration dependence of the molar conductivity of an electrolyte solution, viz., 1 1 c = + ° K ( ° )2 where c is the solute concentration, K is the equilibrium constant for dissociation of the solute, and ° is the conductivity at c = 0. Ounce (oz) - A non-SI unit of mass. The avoirdupois ounce equals 28.34952 g, while the troy ounce equals 31.10348 g. Overpotential () - In an electrochemical cell, the difference between the potential of an electrode and its zero-current value. Oximes - Compounds of structure R2C=NOH derived from condensation of aldehydes or ketones with hydroxylamine. Oximes from aldehydes may be called aldoximes; those from ketones may be called ketoximes. [5] Oxo compounds - Compounds containing an oxygen atom, =O, doubly bonded to carbon or another element. The term thus embraces aldehydes, carboxylic acids, ketones, sulfonic acids, amides and esters. [5] Ozonides - The 1,2,4-trioxolanes formed by the reaction of ozone at a carbon-carbon double bond, or the analogous compounds derived from acetylenic compounds. [5] Pair production - A process in which a photon is converted into a particle and its antiparticle (e.g., an electron and positron) in the electromagnetic field of a nucleus. Paraffins - Obsolescent term for saturated hydrocarbons, commonly but not necessarily acyclic. Still widely used in the petrochemical industry, where the term designates acyclic saturated hydrocarbons, and stands in contradistinction to naphthenes. [5] Paramagnetism* - A type of magnetism characterized by a positive magnetic susceptibility, so that the material becomes weakly magnetized in the direction of an external field. The magnetization disappears when the field in removed. In the simplest approximation (Curie's law) the susceptibility is inversely proportional to temperature. Parity - The property of a quantum-mechanical wave function that describes its behavior under the symmetry operation of coordinate inversion. A parity of +1 (or even) is assigned if the wave function does not change sign when the signs of all the coordinates are changed; the parity is -1 (or odd) if the wave function changes sign under this operation. Parsec (pc) - A unit of distance defined as the distance at which 1 astronomical unit (AU) subtends an angle of 1 second of arc. It is equal to 206264.806 AU or 3.085678 × 1016 m. Particle induced x-ray emission (PIXE) - See Techniques for Materials Characterization, page 12-1.
Toxicity, monitoring and biodegradation of organophosphate pesticides: A review
Published in Critical Reviews in Environmental Science and Technology, 2019
Gurpreet Kaur Sidhu, Simranjeet Singh, Vijay Kumar, Daljeet Singh Dhanjal, Shivika Datta, Joginder Singh
Organophosphate pesticides are utilized broadly around the world, and harming by these chemical agents, especially in developing countries, is a genuine general health issue. The toxico-kinetics and toxico-dynamics of organophosphate pesticide poisoning vary not just with the route and extent of exposure, yet additionally with the chemical structure of the pesticide. The component of lethality is the restraint of acetylcholinesterase, bringing about an aggregation of the neurotransmitter acetylcholine and the stimulation of acetylcholine receptors. The standard treatment consists of reactivation of the inhibited acetylcholinesterase with an oxime antidote and reversal of the biochemical effects of acetylcholine with atropine. Patients who receive treatment promptly usually recover from acute toxicity but may suffer from neurologic sequelae. Lemna bioassay is the most standardized and widely accepted plant bioassay for aquatic ecotoxicology (Mkandawire, Teixeira da Silva, & Dudel, 2014).
Dioxido-vanadium(V) complex catalyzed oxidation of alcohols and tandem synthesis of oximes: a simple catalytic protocol for C–N bond formation
Published in Journal of Coordination Chemistry, 2021
Oximes are an important class of nitrogenous compounds with wide application in the synthesis of fine chemicals, medicines, and biologically active compounds [27]. Oximes are a precursor for synthesis of many important functional groups like amines, nitriles, nitrile oxides and amides [28]. Many efforts have been made to develop efficient procedures to construct these important compounds. The classic method to prepare this functionality is based on reaction of hydroxylamine hydrochloride with a carbonyl compound in the presence of a stoichiometric amount of base [29]. Herein, we describe a protocol for synthesis of oximes from alcohols using tandem synthesis without going through ketones or aldehydes.
Exogenous acetone O-(2-naphthylsulfonyl)oxime improves the adverse effects of excess copper by copper detoxification systems in maize
Published in International Journal of Phytoremediation, 2023
In organic chemistry, oxime is an imine, with the general formula RR’C = N−OH, where R is an organic side-chain and R’ may be hydrogen, forming an aldoxime, or another organic group, forming a ketoxime. For plant growth and development, oximes facilitate a number of processes that are important. The best example of this is the plant hormone auxin, from the oxime class, which was unearthed in the 1930s (Mano and Nemoto 2012). It has been determined that oxaloacetate oxime released from root nodules of legumes is associated with nitrogen fixation, while nitrite release is also associated with further metabolic pathways of the oxime (Virtanen and Laine 1939). Natural and chemically synthesized oximes play so many important roles in plant metabolism, defense, and communication as mentioned by authors (Clausen et al. 2015; Knoch et al. 2016). As a result of the literature review, it has been shown that various synthetic sulfonate-derived oximes have antimicrobial, antifungal, antiviral, anticancer, antihypertension, neuroprotective effect, enzyme inhibition, antioxidant, heavy metal chelator, and antitubercular properties (Gabr et al. 2015; Mishra et al. 2019; Venugopala et al. 2019; Lasri et al. 2020; Savall et al. 2020; Surwase et al. 2020; Zhmurenko et al. 2020; Asif and Imran 2021; Popli et al. 2021; Taslimi et al. 2021; Korkmaz and Bursal 2022; Yetişsin and Kardeş 2022). While these studies provide important information about the effects of sulfonate derivatives, they emphasize the importance of sulfonate derivatives in many areas related to the problems that human beings may face today and in the future. Acetone O-(2-naphthylsulfonyl)oxime (NS), a sulfonate-derived oxime, has a molecular weight of 263 g mol−1. The C = C double bond present in the molecule is more prone to the incorporation of radicals than C = N or C = S bonds, and the C = C bond has less energy compared to the conversion of C = N or C = S bonds to C–N or C–S. The possibility of conversion to C–C indicates that NS may have antioxidant potential. Thanks to the C = N, S = O, and C = C structures in the structure of NS, it can be said that radicals can be attached to these structures. In addition, conjugation in the structure can increase the stability of radicals and add antioxidant properties to the structure (Korkmaz and Duran 2021; Korkmaz 2021a, 2021b) (Figure 2).