The design of new dual-function inhibitors simultaneously preventing hydrate formation and corrosion is a relevant issue for the oil and gas industry. The structure-property relationship for a promising class of hybrid inhibitors based on waterborne polyurethanes (WPU) was studied in this work. Variation of diethanolamines differing in the size and branching of N-substituents (methyl, n-butyl, and tert-butyl), as well as the amount of these groups, allowed the structure of polymer molecules to be preset during their synthesis. To assess the hydrate and corrosion inhibition efficiency of developed reagents pressurized rocking cells, electrochemistry and weight-loss techniques were used. A distinct effect of these variables altering the hydrophobicity of obtained compounds on their target properties was revealed. Polymers with increased content of diethanolamine fragments with n- or tert-butyl as N-substituent (WPU-6 and WPU-7, respectively) worked as dual-function inhibitors, showing nearly the same efficiency as commercial ones at low concentration (0.25 wt%), with the branched one (tert-butyl; WPU-7) turning out to be more effective as a corrosion inhibitor. Commercial kinetic hydrate inhibitor Luvicap 55 W and corrosion inhibitor Armohib CI-28 were taken as reference samples. Preliminary study reveals that WPU-6 and WPU-7 polyurethanes as well as Luvicap 55 W are all poorly biodegradable compounds; BODt/CODcr (ratio of Biochemical oxygen demand and Chemical oxygen demand) value is 0.234 and 0.294 for WPU-6 and WPU-7, respectively, compared to 0.251 for commercial kinetic hydrate inhibitor Luvicap 55 W. Since the obtained polyurethanes have a bifunctional effect and operate at low enough concentrations, their employment is expected to reduce both operating costs and environmental impact.
The article discusses a new methodology for assessing the negative impact of nuclear energy on agricultural land. The necessity of assessing from a financial point of view the negative impact of nuclear energy on agricultural land and the environment is substantiated. Methods are proposed for assessing the financial damage of the negative impact of nuclear energy based on an analysis of the state of the soil and the living world. Examples of calculations of damage in monetary terms for the Russian Federation from the negative impact on the basis of studies of the state of the environment on agricultural land are presented.
The article is devoted to improving the method of testing the wear resistance of friction pairs in a wide range of hardness by embedding a roller into a flat surface of the material under study (sample), first proposed by M. V. Lomonosov. The formula for estimating the volumetric wear resistance from linear depending on the specific pressure is proved. According to the new method, the relative wear resistance of materials in a wide hardness range was evaluated.
The using laser ablation of massive selenium targets, aqueous colloids of selenium nanoparticles were obtained. The resulting nanoparticles are monodisperse in size and mass. The paper presents the optical properties of nanoparticles, morphology and composition. It has been shown that selenium nanoparticles do not significantly affect the development of plants under reference conditions, but effectively level the effects of hyperthermia. The most effective concentration of selenium nanoparticles in the soil is a concentration of 10 μg / kg.
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