Evaluation of metallurgical creep risk factors for 9 wt.% Cr steels

9 wt.% Cr steels are essential for components in powerplant applications, such as combined cycle or coal-fired systems, typically operating at 600~650°C. These steels have a martensitic microstructure strengthened by stabilizing precipitates. However, inclusions, and the evolution of second-phase particles can introduce metallurgical risks related to creep. This research is aimed at developing a deep and quantitative understanding of these metallurgical risk factors in a range of 9 wt.% Cr steels and establishing their correlation with creep behaviour. The study involved extensive microstructural characterisation of both as-received and creep tested samples. This data can facilitate the correlation of microstructural changes with creep performance, offering valuable insights to alloy designers and steel manufacturers for optimizing the composition and fabrication process.As-received and creep tested 9 wt.% Cr steel samples were prepared and characterized using a range of complementary microscopy techniques, including focused ion beam (FIB) microscopy, field emission gun scanning electron microscopy (FEG-SEM), transmission electron microscopy (TEM), and electron backscattered diffraction (EBSD). The experimental aspect of this study focused on examining microstructural changes in 9 wt.% Cr steels in their as-received conditions compared to after creep exposure. To investigate the phase stability and the effects of various alloying elements on 9 wt.% Cr steels, thermodynamic calculations were performed using their chemical compositions as input data. This analysis predicted the influence of several key alloying elements, such as B, C, N, Mo, W, Ta, and Nb, on the formation of secondary phases, such as M23C6, Laves phase, Z phase, and MX. Additionally, the iii calculations explored the conditions under which inclusions would form, providing a deeper understanding of the material's behaviour.Second phase particles are rigorously identified and quantified using various techniques in this study, and the results are systematically compared using different data collection methods. No association was observed between creep cavities and M23C6 or Laves phase particles. Additionally, this study establishes a link between creep cavities and inclusions. It uses a comprehensive approach to identify and quantify both cast pores and creep cavities, revealing their growth and coalescence during creep exposure. In-depth 3D investigations provide overwhelming evidence confirming a strong association between Ta-enriched particles and creep cavities, demonstrating the value of 3D microstructure reconstructions as a powerful tool for better understanding creep risk factors.A coherent linkage between distinct second-phase particles and the damage that occurs during creep tests in these 9 wt.% Cr steels during creep tests was established through a meticulously crafted research methodology. Furthermore, this approach has the potential to be applied more broadly to various steel alloys.</p

In-situ formation of polyvinylidene fluoride microspheres within polycaprolactone electrospun mats

© 2019 This study discusses the manufacture of hierarchical composite membranes via the combination of electrospinning and vapour-induced phase separation (VIPS). The fabrication approach here proposed makes possible the in-situ generation of polyvinylidene fluoride (PVDF) spherical microparticles within electrospun nonwoven mats of polycaprolactone (PCL) fibres. Morphological investigations of the PCL-PVDF membranes show that the PVDF microspheres are distributed within the whole volume of the electrospun mats and, depending on the PVDF concentration used for the VIPS process, they can form permanent joints between fibres. Consequently, the fibre-particle systems exhibit increased Young's modulus and tensile strength (up to 1.7-fold increase) if compared to PCL electrospun mats, while maintaining a porous structure. The results of this study provide a new platform for the development of fibres-based systems that find application as scaffolds for tissue engineering, drug delivery devices, filtration elements for water, wastewater and air treatment

Micelle-Induced Self-Assembling Protein Nanowires: Versatile Supramolecular Scaffolds for Designing the Light-Harvesting System

Organic nanoparticle induced self-assembly of proteins with periodic nanostructures is a promising and burgeoning strategy to develop functional biomimetic nanomaterials. Cricoid proteins afford monodispersed and well-defined hollow centers, and can be used to multivalently interact with geometrically symmetric nanoparticles to form one-dimensional protein nanoarrays. Herein, we report that core-cross-linked micelles can direct cricoid stable protein one (SP1) to self-assembling nanowires through multiple electrostatic interactions. One micelle can act as an organic nanoparticle to interact with two central concaves of SP1 in an opposite orientation to form a sandwich structure, further controlling the assembly direction to supramolecular protein nanowires. The reported versatile supramolecular scaffolds can be optionally manipulated to develop multifunctional integrated or synergistic biomimetic nanomaterials. Artificial light-harvesting nanowires are further developed to mimic the energy transfer process of photosynthetic bacteria for their structural similarity, by means of labeling donor and acceptor chromophores to SP1 rings and spherical micelles, respectively. The absorbing energy can be transferred within the adjacent donors around the ring and shuttling the collected energy to the nearby acceptor chromophore. The artificial light-harvesting nanowires are designed by mimicking the structural characteristic of natural LH-2 complex, which are meaningful in exploring the photosynthesis process <i>in vitro</i>

Table1_Efficacy and safety of traditional Chinese medicine external washing in the treatment of postoperative wound of diabetes complicated with anal fistula: Study protocol of a randomized, double-blind, placebo-controlled, multi-center clinical trial.DOC

Introduction: Anal fistula is one of the commonest ailments seen by anorectal surgeons as surgery is currently the preferred treatment for it. Diabetes mellitus is a risk factor that can lead to slow wound healing after anal fistula surgery. Because of the large postoperative wound surface of anal fistula, patients with diabetes can have an increased probability of wound infection, which makes it hard to heal. There is an extensive clinical experience for wound healing in traditional Chinese medicine (TCM). The Jiedu Shengji decoction (JSD) is a widely used external washing decoction in clinical practice. However, the current evidence on it is still insufficient. Therefore, we report this carefully designed clinical trial to assess the efficacy and safety of JSD in the treatment of postoperative wounds in diabetic patients with anal fistula.Methods and analysis: This study was designed to be a randomized, double-blind, placebo-controlled, multi-center clinical trial. There were 60 eligible participants who were randomized at a 1:1 ratio to the intervention and placebo groups. Both groups received the same standard treatment. The intervention group was given external washing decoction of TCM (JSD), while the placebo group was given the placebo made of excipients and flavoring agents. The main outcome measures include wound healing, distribution of wound pathogens, levels of inflammatory mediators, and blood glucose. The secondary outcome measures included lipids, the quality of the life evaluation scale (Short-Form Health Survey 36). Assessments were performed before the start of the study, at 1st, 2nd, 3rd, and 4th weeks after the intervention, and at 8th, 12th, and 16th follow-up weeks.Discussion: The clinical study we proposed will be the first randomized, double-blind, placebo-controlled, multi-center clinical trial study to assess the efficacy and safety of TCM external washing (JSD) in the treatment of postoperative wounds in diabetic patients with anal fistula.Ethics and dissemination: The Medical Ethics Committee of Hospital of Chengdu University of Traditional Chinese Medicine has reviewed this study protocol and gave its approval and consent on 17 March, 2022 (Ethical Review Number: 2022KL-018).</p

Table2_Efficacy and safety of traditional Chinese medicine external washing in the treatment of postoperative wound of diabetes complicated with anal fistula: Study protocol of a randomized, double-blind, placebo-controlled, multi-center clinical trial.DOCX

Introduction: Anal fistula is one of the commonest ailments seen by anorectal surgeons as surgery is currently the preferred treatment for it. Diabetes mellitus is a risk factor that can lead to slow wound healing after anal fistula surgery. Because of the large postoperative wound surface of anal fistula, patients with diabetes can have an increased probability of wound infection, which makes it hard to heal. There is an extensive clinical experience for wound healing in traditional Chinese medicine (TCM). The Jiedu Shengji decoction (JSD) is a widely used external washing decoction in clinical practice. However, the current evidence on it is still insufficient. Therefore, we report this carefully designed clinical trial to assess the efficacy and safety of JSD in the treatment of postoperative wounds in diabetic patients with anal fistula.Methods and analysis: This study was designed to be a randomized, double-blind, placebo-controlled, multi-center clinical trial. There were 60 eligible participants who were randomized at a 1:1 ratio to the intervention and placebo groups. Both groups received the same standard treatment. The intervention group was given external washing decoction of TCM (JSD), while the placebo group was given the placebo made of excipients and flavoring agents. The main outcome measures include wound healing, distribution of wound pathogens, levels of inflammatory mediators, and blood glucose. The secondary outcome measures included lipids, the quality of the life evaluation scale (Short-Form Health Survey 36). Assessments were performed before the start of the study, at 1st, 2nd, 3rd, and 4th weeks after the intervention, and at 8th, 12th, and 16th follow-up weeks.Discussion: The clinical study we proposed will be the first randomized, double-blind, placebo-controlled, multi-center clinical trial study to assess the efficacy and safety of TCM external washing (JSD) in the treatment of postoperative wounds in diabetic patients with anal fistula.Ethics and dissemination: The Medical Ethics Committee of Hospital of Chengdu University of Traditional Chinese Medicine has reviewed this study protocol and gave its approval and consent on 17 March, 2022 (Ethical Review Number: 2022KL-018).</p

Quantum-Dot-Induced Self-Assembly of Cricoid Protein for Light Harvesting

Stable protein one (SP1) has been demonstrated as an appealing building block to design highly ordered architectures, despite the hybrid assembly with other nano-objects still being a challenge. Herein, we developed a strategy to construct high-ordered protein nanostructures by electrostatic self-assembly of cricoid protein nanorings and globular quantum dots (QDs). Using multi­electrostatic interactions between 12mer protein nanoring SP1 and oppositely charged CdTe QDs, highly ordered nanowires with sandwich structure were achieved by hybridized self-assembly. QDs with different sizes (QD1, 3–4 nm; QD2, 5–6 nm; QD3, ∼10 nm) would induce the self-assembly protein rings into various nanowires, subsequent bundles, and irregular networks in aqueous solution. Atomic force microscopy, transmission electron microscopy, and dynamic light scattering characterizations confirmed that the size of QDs and the structural topology of the nanoring play critical functions in the formation of the superstructures. Furthermore, an ordered arrangement of QDs provides an ideal scaffold for designing the light-harvesting antenna. Most importantly, when different sized QDs (<i>e.g.</i>, QD1 and QD3) self-assembled with SP1, an extremely efficient Förster resonance energy transfer was observed on these protein nanowires. The self-assembled protein nanostructures were demonstrated as a promising scaffold for the development of an artificial light-harvesting system

Supplementary document for Long-term monitoring chlorophyll-a concentration using HJ-1 A/B imagery and machine learning algorithms in typical lakes, a cold semi-arid region - 6943993.pdf

Supplemental Documen

Construction of GPx Active Centers on Natural Protein Nanodisk/Nanotube: A New Way to Develop Artificial Nanoenzyme

Construction of catalytic centers on natural protein aggregates is a challenging topic in biomaterial and biomedicine research. Here we report a novel construction of artificial nanoenzyme with glutathione peroxidase (GPx)-like function. By engineering the surface of tobacco mosaic virus (TMV) coat protein, the main catalytic components of GPx were fabricated on TMV protein monomers. Through direct self-assembly of the functionalized viral coat proteins, the multi-GPx centers were installed on these well-defined nanodisks or nanotubes. With the help of muti-selenoenzyme centers, the resulting organized nanoenzyme exhibited remarkable GPx activity, even approaching the level of natural GPx. The antioxidation study on subcell mitochondrial level demonstrated that virus-based nanoenzyme exerted excellent capacity for protecting cell from oxidative damage. This strategy represents a new way to develop artificial nanoenzymes

GSH-dependent antioxidant defense contributes to the acclimation of colon cancer cells to acidic microenvironment

<p>Due to increased glycolysis and poor local perfusion, solid tumors are usually immersed in an acidic microenvironment. While extracellular acidosis is cytotoxic, cancer cells eventually become acclimated to it. While previous studies have addressed the acute effect of acidosis on cancer cells, little is known about how cancer cells survive chronic acidosis. In this study we exposed colorectal cancer (CRC) cells (HCT15, HCT116 and LoVo) to acidic pH (pH 6.5) continuously for over three months and obtained CRC cells that become acclimated to acidic pH, designated as CRC-acidosis-acclimated or CRC-AA. We unexpectedly found that while acute exposure to low pH resulted in an increase in the level of intracellular reactive oxygen species (ROS), CRC-AA cells exhibited a significantly reduced level of ROS when compared to ancestor cells. CRC-AA cells were found to maintain a higher level of reduced glutathione, via the upregulation of CD44 and glutathione reductase (GSR), among others, than their ancestor cells. Importantly, CRC-AA cells were more sensitive to agents that deplete GSH. Moreover, downregulation of GSR by RNA interference was more deleterious to CRC-AA cells than to control cells. Together, our results demonstrate a critical role of glutathione-dependent antioxidant defense in acclimation of CRC cells to acidic extracellular pH.</p

Additional file 1 of Spatial effects of air pollution on the economic burden of disease: implications of health and environment crisis in a post-COVID-19 world

Additional file 1: Appendix Fig. 1. The robustness test results of AQI related results