Search

Analyzed here in the paper are the regularities of influences on the tensile test result by various factors, including sampling, specimen flattening and processing of the linepipe and the tensile ratio. And the control requirements for improving the data accuracy of the tensile test are presented. It is concluded via the analysis that in case of taking the sample from the steel pipe with flame cutting method, the length of the sample should be determined as per the OD and WT of the pipe, and the test sample should not be taken at a position under 50 mm; the overall length of the sample can be properly reduced by means of the on-line water-cooling process; compared with the room temperature strain aging, the strain aging with the temperature over 210 V, produces more obvious influence on the tensile property, while compared with the specimen flattening frequency, the unevenness of the plate tensile specimen produces much more influence on the yield strength. [ABSTRACT FROM AUTHOR]

Currently reported adsorbents for wastewater purification generally have only limited adsorption capacity and low adsorption rate towards dye contaminants. In this work, KH570-modified magnetic hydrogel nanocomposites (KH570-mHNCs) with semi-IPNs structure were prepared based on poly (acrylamide-co-acrylic acid), polyvinyl pyrrolidone (PVP), and KH570-modified magnetic nanoparticles, and it exhibited high absorption capacity and absorption rate for methylene blue dye. KH570-mHNCs had a rough surface with many porous and gully structures, and FTIR results preliminarily confirmed the target structure of KH570-mHNCs. KH570-mHNCs could rapidly absorb methylene blue by approaching absorption equilibrium at 90 min. Dye absorption of KH570-mHNCs had maximum dye absorption capacity at pH = 8, and methylene blue adsorption capacity was 255.4 mg/g, 326.3 mg/g, and 418.5 mg/g in the condition of initial dye concentrations of 700 mg/L, 900 mg/L, and 1100 mg/L, respectively. Methylene blue adsorption isotherms and kinetics conformed to the Langmuir model and pseudo-second-order kinetic model, respectively. Methylene blue adsorption for KH570-mHNCs was a spontaneous, exothermal, and entropy reduction process. In addition, KH570-mHNCs had good magnetic response, desorption, and reusability, which made it a potential application in the field of methylene blue removal from the aqueous solution. [ABSTRACT FROM AUTHOR]