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Fricke gel dosimeters have great potential for three‐dimensional (3D) dose verification in radiation therapy; however, they suffer from time‐dependent ion diffusion after irradiation, severely affecting their stability and reliability. In this work, a pullulan‐based amphiphilic molecule was synthesized, characterized, and self‐assembled into nanogels. Nanogel structures were embedded into gel dosimeters to reduce the diffusion rates, and radiation‐sensitive nanogel‐incorporated Fricke hydrogel nanocomposites were prepared successfully. The results demonstrated that the diffusion coefficient of improved dosimeters was reduced to 0.125 ± 0.001 mm2 h−1, while maintaining the high optical dose sensitivity (0.0410 ± 0.0004 Gy−1 cm−1). It provides a powerful tool toward the practical application of 3D dosimeters. [ABSTRACT FROM AUTHOR]

We performed a meta‐analysis to evaluate the effect of negative pressure wound therapy compared with conventional wound dressings on closed incisions in orthopaedic trauma surgery. A systematic literature search up to October 2021 was done and 12 studies included 3555 subjects with closed incisions in orthopaedic trauma surgery at the start of the study: 1833 of them were provided with negative pressure wound therapy and 1722 were conventional wound dressings. They were reporting relationships about the effect of negative pressure wound therapy compared with conventional wound dressings on closed incisions in orthopaedic trauma surgery. We calculated the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) to assess the effect of negative pressure wound therapy compared with conventional wound dressings on closed incisions in orthopaedic trauma surgery using the dichotomous and continuous methods with a random or fixed‐effect model. Negative pressure wound therapy had significantly lower deep surgical site infection (OR, 0.65; 95% CI, 0.48–0.88, P =.005), superficial surgical site infection (OR, 0.23; 95% CI, 0.11–0.49, P =.31), and wound dehiscence (OR, 0.41; 95% CI, 0.21–0.80, P =.009) compared with conventional wound dressings in subjects with closed incisions in orthopaedic trauma surgery. However, negative pressure wound therapy had no significant effect on the length of hospital stay (MD, 0.29; 95% CI, −2.00‐ 2.58, P =.80) compared with conventional wound dressings in subjects with closed incisions in orthopaedic trauma surgery. Negative pressure wound therapy had significantly lower deep surgical site infection, superficial surgical site infection, and wound dehiscence; however, negative pressure wound therapy had no beneficial effect on the length of hospital stay compared with conventional wound dressings in subjects with closed incisions in orthopaedic trauma surgery. Further studies are required to validate these findings. [ABSTRACT FROM AUTHOR]

Abstract: Effect of H2S partial pressure on the tensile properties of A350LF2 steel with and without pre-immersion was investigated by slow strain rate testing and electrochemical impedance spectroscopy. The results show that relative tensile strength and plasticity loss increased with increasing in the absence and presence of pre-immersion. Greater tensile property damage occurred in steel without pre-immersion compared to that with pre-immersion. The relative plasticity loss increment of steel without pre-immersion was larger than that with pre-immersion as was increased from 0.1MPa to 1.6MPa. Fractography exhibited flat brittle fracture on the samples without pre-immersion and mixed ductile-brittle fracture on the pre-immersed samples. Furthermore, the embrittled regions on the fracture surface of pre-immersed specimens increased with . In addition, no cracks existed in the steel after pre-immersion. The cracks on the fracture surface of steel could be attributed to the combination of tensile stress and high hydrogen concentration induced by the hydrogen diffusion and accumulation during the tensile test. [Copyright &y& Elsevier]

Highlights: [•] Tensile and impact behavior of the steel had different change law with H2S pressure. [•] Charpy absorbed energy exhibited no obvious change with increasing H2S pressure. [•] Fractography showed mixed ductile–brittle rupture for the corroded mechanical samples. [•] Hydrogen has a profound effect on the tensile and impact behavior of steel. [•] A probable mechanism is proposed to interpret the tensile and impact results. [Copyright &y& Elsevier]

Abstract: The tensile properties and fracture behaviour of A350LF2 steels after exposure to wet H2S environments were investigated by corrosion and tensile testing. The results suggest that relative tensile strength and plasticity loss increased as hydrogen concentration increased. Greater tensile property damage occurred in steel that contained more large-size inclusions. When hydrogen was released, the degree of relative strength and plasticity loss decreased. Fractography of the corroded samples exhibited mixed ductile–brittle rupture. Fractured areas with quasi-cleavage features increased with increasing hydrogen concentration. Flakes appeared in the steel with a low sulphur content and low hydrogen concentration. [Copyright &y& Elsevier]

The effect of H 2 /CO 2 partial pressure ratio on the tensile properties of X80 pipeline steel in the absence and presence of water were investigated by slow strain rate test (SSRT) and scanning electron microscope (SEM) measurements in this paper. The results show that the tensile strength and elongation to failure of X80 pipeline steel in H 2 /CO 2 atmosphere were deteriorated significantly. The relative tensile strength and plasticity loss of X80 pipeline steel increased with increasing H 2 /CO 2 partial pressure ratio in the absence of water. The increasing volume fraction of hydrogen gas is the key influencing factor in this condition. For the H 2 /CO 2 environments in the presence of water, the relative tensile property loss decreased first and then increased with H 2 /CO 2 partial pressure ratio. The probable reason is that the corrosion process changed gradually from CO 2 -dominant to H 2 -dominant. Water played a significant role in the tensile property damage of X80 pipeline steel in the H 2 /CO 2 environments. [ABSTRACT FROM AUTHOR]

Tensile properties and fracture behavior of X80 pipeline steel exposed to corrosion environments with different H 2 S/CO 2 partial pressure ratios were investigated through slow strain rate tests (SSRT). The results show that the tensile properties of X80 steel were damaged in H 2 S/CO 2 environments. The tensile strength and elongation to failure of X80 steel decreased significantly with increasing H 2 S/CO 2 partial pressure ratio. The fracture appearance of the corroded samples exhibited mixed ductile–brittle rupture. Fractured areas with quasi-cleavage features increased as H 2 S/CO 2 partial pressure ratio increased. Different types of secondary cracks can be identified on the SSRT specimens in the corrosion environments with different H 2 S/CO 2 partial pressure ratios. [ABSTRACT FROM AUTHOR]

The tensile and impact properties of X70 pipeline steels exposed to wet H 2 S environments were investigated by corrosion and mechanical testing. The results suggest that the Charpy absorbed energy, tensile strength and reduction in area of X70 steel decreased after H 2 S corrosion. When hydrogen was released, Charpy absorbed energy and reduction in area exhibited a certain recovery. Fractography of the tensile and impact specimens exhibited mixed ductile–brittle rupture after corrosion and hydrogen release. Fractured areas with brittle features diminished after hydrogen release. Hydrogen was closely associated with mechanical property degradation and fracture features. [ABSTRACT FROM AUTHOR]