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Applied Chemistry and Physics
Published in Robert A. Burke, Applied Chemistry and Physics, 2020
The structural formula illustrates the way the bonding takes place between the atoms of elements in a compound. The molecular formula shows the numbers of each atom in the compound. Responders may encounter the molecular formula along with the name; however, it is unlikely that they will see a structural formula in the field. As can be seen with the structural formula of carbon disulfide, there are two bonds between the sulfur and the carbon. This configuration of bonding is referred to as double bonding. Double bonds are very unstable; which is why carbon disulfide is so very flammable. Most compounds that have this carbon to carbon double bond are unstable. Triple bonds are even more unstable so these compounds are not usually shipped in transportation except for welding bottles of acetylene. Acetylene is the only commercially valuable triple-bonded material you are likely to encounter.
Subsurface Processes
Published in Stephen M. Testa, Geological Aspects of Hazardous Waste Management, 2020
A mole of any substance is the formula weight of the substance in grams. For example, the atomic weight of sodium (Na) is 22.99, so 1 mol of Na weighs 22.99 g. The atomic weight of chlorine (Cl) is 35.45, so 1 mol of Cl weighs 35.45 g. The molecular weight of common salt (NaCl) is 22.99 + 35.45 = 58.44, so 1 mol of NaCl weighs 58.44 g and contains 1 mol of Na and 1 mol of Cl. The atomic weight of oxygen (O) is 16.0, so 1 mol of O weighs 16.0 g; however, 1 mol of molecular oxygen (O2), which has a molecular weight of 32.0, weighs 32.0 grams and contains 2 mol of atomic oxygen. Nitrate ion (NO3−) has 1 mol of nitrogen (14.0 g), thus, 1 mol of NO3_ weighs 62 g. Note that electrons are essentially weightless, so the charge does not matter as far as weight is concerned.
Determination and correlation of solubility and Thermodynamic properties of allantoin in four binary solvents from 288.15 K to 333.15 K
Published in Chemical Engineering Communications, 2023
Junlan Liu, Yanyang Wu, Kui Chen, Bin Wu, Lijun Ji
Allantoin (C4H6N4O3, CAS Registry No: 97-59-6) exists in plants, bacteria, and most mammals (Zhang et al. 2021). The structural formula was shown in Figure 1. As allantoin can have an exfoliating effect, speed up skin cell regeneration, and help the skin smooth and soft (Xie et al. 2022; Zhang et al. 2021), it has been widely used in facial creams, sunscreen products, lipsticks, etc. Meanwhile, it has been used as a drug for skin defective diseases due to its antioxidant and anti-inflammatory activities (Ahn et al. 2014; Sakthiguru and Sithique 2020; Valle et al. 2020). In addition, it can be been applied as a nitrogenous fertilizer in agriculture field as well (Fahad et al. 2019; Liu et al. 2020; Moriyama et al. 2020). However, its application has been restricted by the low solubility. It could be increased when the average particle size decreased down to 10 μm (Sarkas 2021), or adding urea derivatives and amino acid analogs into drug formulations (Zhan et al. 2021; Zhang 2008). The detailed solubility data of allantoin, which is crucial for the design and optimization of crystallization and its application, have not been reported in literature.
Laboratory development and evaluation of an oleylamine curing Epoxy Asphalt
Published in International Journal of Pavement Engineering, 2022
Fenglei Zhang, Lei Zhang, Xiaoxuan Guo, Dongliang Hu, Zhenyu Cai, Kai Huang
According to the investigation of the commercial epoxy resin in 2.1, the main agent of OCEA used in this paper is bisphenol A epoxy resin produced by Baling Petrochemical Company. The chemical structural formula is shown in Figure 2a. The relevant properties are shown in Table 1.According to the infrared analysis of the commercial epoxy asphalt curing agent in 2.1, it can be found that the type of curing agent used is the fatty amine curing agent. Since the epoxy asphalt needs to be cured at room temperature after paving, the amine curing agent can continue to have a ring-opening reaction with epoxy resin at room temperature. This paper's aliphatic amine curing agent is easy to fuse with non-polar asphalt because of its non-polar long chain. The amino group at the end can react with epoxy resin to form a 3D network structure. The long aliphatic chain can improve the toughness of cured epoxy resin. Amine cured epoxy resin has high strength, excellent adhesion, alkali, inorganic acid resistance, and good resistance to moisture damage and solvent resistance. Therefore, the oleylamine curing agent (Boca chemical) is selected in this paper, and the structural formula is shown in Figure 2b. Comparing it with the commercial curing agent, the relevant basic properties are shown in Table 2.
Studies on interfacial interactions between petroleum sulfonate and sulfobetaine molecules by rheological measurements
Published in Journal of Dispersion Science and Technology, 2021
Zhao-yang Guo, Xu-long Cao, Lan-lei Guo, Zhi-yi Zhao, Bao-dong Ma, Lei Zhang, Lu Zhang, Sui Zhao
In this paper, the zwitterionic surfactant alkyl sulfobetaine (ASB) was synthesized by our laboratory with purity more than 95% and checked by 1 H NMR spectroscopy. Scheme 1 shows the structural formula of ASB. The anionic surfactant of petroleum sulfonate (KPS) used in this paper was obtained from Kelamayi oilfield of China. Kerosene was further purified by glass chromatography column filled with the silica gel layer until the stable interfacial tension between kerosene and water reaches about 40 mN/m. Ultrapure water with 18.2 MΩ•cm resistivity was used in the preparation of the simulate water, which was employed to prepare surfactants solution for the experiments. The compositions of the formation brine with a TDS of 10260 mg/L were reported early.[7]