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This paper focuses on the stabilization problem for rectangular descriptor fractional order systems (FOSs) with $0

The synthesized imidazoline phosphate quaternary ammonium salt has low stability, which is spontaneously and rapidly hydrolyzed to the long-chain fatty acid amide (LFA). The hydrolysate (LFA) has been found to be an efficient inhibitor for Q235 steel against CO2 corrosion, which yields a maximum value above 90% at a concentration of 1000 mg L−1. The LFA inhibitor acts as an anodic type inhibitor and its inhibition mechanism is a “negative catalysis effect”. The heteroatoms in the acyl, amine and phosphate groups in the LFA molecule are the active centers to bond with Fe atoms to form a chemisorbed film on the steel surface.

The anticorrosion performance of two pyrimidine derivatives 2-mercaptopyrimidine (2-MP) and 4-methyl-2-mercaptopyrimidine (4 M−2MP) on Q235 plain carbon steel in CO2-saturated 3 wt% NaCl aqueous solution has been comparatively examined utilizing weight loss methods, electrochemical techniques as well as surface analysis. The results indicate that the two kinds of pyrimidine derivatives serve as mixed-type inhibitors and show excellent and long-lasting inhibitory effect for Q235 steel against general and localized corrosion even at very low concentrations. The inhibition efficiencies increase with a rise in concentration but decrease with temperature rising. Compared with 4 M−2MP inhibitor, the 2-MP exhibits stronger adsorption ability and higher inhibition efficiency due to the existence of two tautomers of thiol and thione forms. The adsorption of both inhibitors over Q235 steel surface can be well fitted by Langmuir adsorption isotherm. The values of standard Gibbs free energy of adsorption ( Δ G a d s 0 ) indicate that both physisorption and chemisorption processes have taken place. Furthermore, thermodynamic parameters are extracted from Langmuir rule to discuss the adsorption mechanism and the XPS analysis is applied to describe the bonding characteristics between inhibitors and steel substrate.

The synthesized imidazoline phosphate quaternary ammonium salt has low stability, which is spontaneously and rapidly hydrolyzed to the long-chain fatty acid amide (LFA). The hydrolysate (LFA) has been found to be an efficient inhibitor for Q235 steel against CO

To explore the gap between women's needs for pregnancy related apps and to evaluate the quality of the top 10 downloaded pregnancy related apps, we designed a cross-sectional study to survey 153 pregnant women. This study showed pregnant women had high requirement against the quality of knowledge content, functions, interface and basic characteristics of apps. The top 10 popular apps showed a range of drawbacks and were far from satisfying the needs of pregnant women.