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Two models for the prediction of corrosion inhibition efficiency of various pure surfactant and mixed surfactants in salt-containing solution are developed, compared, and validated. The two prediction models are based on a modified Langmuir adsorption (MLA) sub-model and a modified Quantitative Structure Activity Relation (MQSAR) sub-model. Each of the sub-models is combined with the critical micelle concentration (cmc) prediction sub-model to create an overall corrosion inhibition prediction model separately. Each of the created overall models is very robust in predicting corrosion inhibition of various surfactants in a variety of testing systems. The model derivation is mainly based on the mixed homologous benzalkonium chlorides in NaCl-containing aqueous solution and further validated using various testing systems of surfactants. The developed corrosion inhibition prediction models provide potential methods to evaluate the effectiveness of various surfactants in corrosion inhibition under various testing solution conditions. In addition, the adsorption and inhibition mechanisms of surfactants in the corresponding testing system were investigated. Carbon steel is widely used for production and transportation pipelines in the oil and gas industries.1-4 However, carbon steel is easily corroded in environments that contain water and carbon dioxide (CO 2 ).3-7 As one of the main corrosion types in the oil and gas industry, CO 2 related corrosion can cause tremendous damage to pipelines and structural components in water and crude oil transportation and thus threaten production and safety. [3][4][5][7][8][9] The annual direct cost of corrosion in United States has been estimated to be around 3.1% of the gross domestic product (GDP). About 3.7% out of the total cost comes from the oil and gas industry, 7,10 which is mainly due to the corrosion of carbon steel. Therefore, the cost of corrosion and safety has led to great interest in controlling CO 2 -related corrosion in various oilfields around the world.The most popular control method is to use organic inhibitors that contain heterocyclic molecules to reduce CO 2 based corrosion on carbon steel. 1,2,[11][12][13][14] Many of the organic inhibitors are surfactants with hydrophilic and hydrophobic molecular sections.The hydrophilic group of surfactant strongly prefers interaction with polar entities such as water, metals, and ions. These organic surfactants adsorb on the metal surface, block the active surface sites, and thereby reduce corrosion attack.11,12 The presence and structure of specific atoms, such as N and O, in surfactants determine the adsorption mechanism and corrosion inhibition efficiency.13,14 Surfactant mixtures have received wide attention in practical applications because of their superior physicochemical properties and capabilities in efficient solubilization, dispersion, suspension, and transportation.15,16 Solutions containing mixed surfactants can often be conveniently tuned to achieve desired properties by adjusting the composition of the mixt...

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SnTe has recently emerged as a 3D crystalline topological insulator exhibiting band inversion at the L point where certain crystalline symmetries allow the protection of robust topological surface states. Synthesis and development of new Dirac materials by disturbing the SnTe symmetry was accomplished by substitution of a Sn vacancy by P that maintains the intrinsic band inversion at the L point but also the direct bandgap reduction upon the incorporation of spin orbit coupling. The exotic morphology of the synthesized P-doped SnTe microneedles produces signal amplification arising from the topological surface states due to the alteration of surface area to volume ratio. Moreover, the modified effective mass, lattice imperfection, and conductivity results in a large memory window ∼3.1 V for field effect transistors accompanied by a large change in current within a certain potential range.