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The effects of quenching and tempering temperatures on the microstructure and mechanccal properties of H13 hot work die steel were rnvestigated by using metallograplic microscopy, scanning electron microscopy, microhardness tesiing,and tensle testing. The findings revealed that secondary tempering treatment and appropriate reduction in tempering temperature result in the effective precipitation of iiner and more dispersed carbides and the complete release of quenching stress. As a resutt, the hardness and toughness of H13 hot work de steel were significantly improved. Notably,when the quenching temperature was 1 000 C and the tempering temperature was 520 C, the mechanical properties are superior, characterized by smaler tempering martenstte size and more uniform structural dsstribution. Under these cond!tions, the hardness measureed 487 HV, the tenslle strength reached 1 779 MPa,and the elongation was 11. 5%. The analysis of the tenslle fracture morphology reveals the presence of numerous dimples in the specimen after the tempering process, indccative of typca! ducile fracture charac t eris i ccs. Fur t hermore,a model was developed to describe t he soft ening behavior of H13 s t eel during t empering n t he t empera t ure range of 520 C to 600 C. [ABSTRACT FROM AUTHOR]

The current investigation delves into the influence of varying cooling rates, encompassing water, rapid quenching oil, and air, on the quench crack susceptibility (QCS) of disc springs. The assessment reveals that the average martensite lath width under water, oil, and air cooling conditions measures 0.61 μm, 0.66 μm, and 1.12 μm, respectively. Correspondingly, the residual austenite content amounts to 6.9%, 8.7%, and 12.3%. Notably, cracks are observed at the disc spring's perimeter during water cooling, whereas oil and air cooling effectively preclude such occurrences. Simulations demonstrate that residual stresses of up to 1011 MPa can arise at the disc spring cross-section corners under water cooling, significantly surpassing the stresses encountered under oil and air cooling, at 440 MPa and 73 MPa respectively. As the microstructure evolves, these residual stresses critically impact the grain boundaries of the original austenite, compromising the buffering capabilities of the martensite phase and residual austenite, thereby enhancing susceptibility to quench cracking. [ABSTRACT FROM AUTHOR]

This article explores the potential use of Janus kinase inhibitors (JAKi) in treating SAPHO syndrome, a rare autoinflammatory disease that affects the skin and skeletal system. JAKi can block the action of various cytokines involved in inflammation, making them potentially more effective than biologics that only target one cytokine. The article presents case reports of SAPHO syndrome patients who experienced symptom improvement after treatment with JAKi, specifically tofacitinib, baricitinib, and upadacitinib. However, more research is needed to validate the efficacy of JAKi in treating SAPHO syndrome, including studies on tapering or discontinuation of JAKi and potential relapses or treatment failures. [Extracted from the article]

Polyoxometalate-based metal-organic frameworks (POMOFs) with bifunctional Lewis-Brønsted acid were designed by confining polyoxometalates (POMs: phosphotungstic acid (PW), phosphomolybdic acid (PMo) or silicotungstic acid (SiW)) within the Zr-MOFs. The confined POMs not only have their own Brønsted acid, but can also regulate the Lewis acid strength of the POMOFs via charge regulation, ultimately allowing the POMOFs to display superior catalytic performance in the tandem catalysis of furfural (FAL) to γ-valerolactone (GVL). Among the three catalysts (POMOF-PW, POMOF-PMo and POMOF-SiW), a complete conversion of FAL was achieved, while POMOF-PW exhibited the highest GVL yield (58.1 %) at 160 °C within 23 h. The leaching experiment and structural characterization of the catalyst before and after recycling confirmed the stability of the catalyst structure. The humin originates from the polymerization of furan ring-containing compounds driven by Brønsted acid. The adsorption configuration of the substrate molecules on the catalyst offers a new explanation for the tandem reaction process, i.e. that perpendicular adsorption performs only the first step of the tandem reaction, while the coexistence of perpendicular and horizontal adsorption permits the entire reaction process. This work gives unique insights into the tandem reaction of FAL and can guide the design of efficient tandem reaction catalysts. A synthetic strategy has been developed to construct polyoxometalate-based metal-organic framework (POMOF) with bifunctional Lewis-Brønsted acid sites by chemically confining polyoxometalates (POM) in metal-organic framework (MOF) channels. Confined POM not only endows the catalyst with Brønsted acid sites, but also enhances the acid strength of the catalyst through charge regulation, which finally promotes the catalyst to exhibit excellent catalytic performance in the multi-step cascade catalysis from furfural (FAL) to γ-valerolactone (GVL). This work also provides insight into the origin and driving sites of the by-product humin, as well as the role of the adsorption configuration in the catalytic process. A look into the future of the multi-step tandem reaction of FAL to GVL is presented. [Display omitted] [ABSTRACT FROM AUTHOR]

• A complete Co doping range up to its solid solubility limit in FeSe have been successfully grown. • The typical lateral size of Fe 1-x Co x Se single crystals is 1–5 mm. • All the samples show metalic behaviour in contrast to a metal insulator transition of Cu doped FeSe. A series of tetragonal Fe 1-x Co x Se single crystals with a complete Co doping range (0 ≤ x ≤ 0.52) up to its solid solubility limit in FeSe have been grown by an eutectic AlCl 3 /KCl molten salt method. The typical lateral size of as-grown Fe 1-x Co x Se single crystals is 1–5 mm. The chemical composition and homogeneity of the crystals was examined by both inductively coupled plasma atomic emission spectroscopy and energy dispersive spectrometer. X-ray diffraction analysis demonstrates that the crystal lattice parameters a and c are both linearly decreased with increasing Co doping level x. In the whole doping range, all the samples show metallic behaviour in contrast to a metal insulator transition of Cu-doped FeSe according to the resistivity measurements. [ABSTRACT FROM AUTHOR]

This work has presented gas sensors based on indium tin oxide (ITO) for the detection of SO2 and NO2. The ITO gas-sensing material was deposited by radio frequency (RF) magnetron sputtering. The properties of gas sensing could be improved by increasing the ratio of SnO2. The response characteristics of the gas sensor for detecting different concentrations of NO2 and SO2 were investigated. In the detection of NO2, the sensitivity was significantly improved by increasing the SnO2 ratio in ITO by 5%, and the response and recovery time were reduced significantly. However, the sensitivity of the sensor decreased with increasing SO2 concentration. From X-ray photoelectron spectroscopy (XPS) analysis, the gas-sensitive response mechanisms were different in the atmosphere of NO2 and SO2. The NO2 was adsorbed by ITO via physisorption but the SO2 had a chemical reaction with the ITO surface. The gas selectivity, temperature dependence, and environmental humidity of ITO-based gas sensors were systematically analyzed. The high detection sensitivity for acidic gas of the prepared sensor presented great potential for acid rain monitoring. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) remains a malignant tumor with high morbidity and mortality, accounting for approximately 1,080,000 diagnosed cases and 770,000 deaths worldwide annually. Disulfidptosis, characterized by the stress-induced abnormal accumulation of disulfide, is a recently identified form of programmed cell death. Substantial studies have demonstrated the significant influence of immune clearance on tumor progression. Therefore, we aimed to explore the intrinsic correlations between disulfidptosis and immune-related genes (IRGs) in GC, as well as the potential value of disulfidptosis-related immune genes (DRIGs) as biomarkers. Methods: This study incorporated the single-cell RNA sequencing (scRNA-seq) dataset GSE183904 and transcriptome RNA sequencing of GC from the TCGA database. Disulfidptosis-related genes (DRGs) and IRGs were derived from the representative literature on both cell disulfidptosis and immunity. The expression and distribution of DRGs were investigated at the single-cell level in different GC cell types. Pearson correlation analysis was used to identify the IRGs closely related to disulfidptosis. The prognostic signature of DRIGs was established using Cox and LASSO analyses. We then analyzed and evaluated the differences in long-term prognosis, Gene Set Enrichment Analysis (GSEA), immune infiltration, mutation profile, CD274 expression, and response to chemotherapeutic drugs between the two groups. A tissue array containing 63 paired GC specimens was used to verify the expression of 4 DRIGs and disulfidptosis regulator SLC7A11 through immunohistochemistry staining. Results: The scRNA-seq analysis found that SLC7A11, SLC3A2, RPN1 and NCKAP1 were enriched in specific cell types and closely related to immune infiltration. Four DIRGs (GLA, HIF-1α, VPS35 and CDC37) were successfully identified to establish a signature to potently predict the survival time of GC patients. Patients with high risk scores generally experienced worse prognoses and exhibited greater resistant to classical chemotherapy drugs. Furthermore, the expression of GLA, HIF-1α, VPS35, CDC37 and SLC7A11 were elevated in GC tissues. A high expression of GLA, HIF-1α, VPS35 or CDC37 was associated with more advanced clinical stage of GC and increased SLC7A11 expression. Conclusion: Current study first highlights the potential value of DRIGs as biomarkers in GC. We successfully constructed a robust model incorporating four DRIGs to accurately predict the survival time and clinicopathological characteristics of GC patients. [ABSTRACT FROM AUTHOR]

In this study, the co-combustion of coal and biomass, and the tri-combustion of coal, biomass, and oil sludge in a 130 t h−1 circulating fluidized bed (CFB) boiler are investigated via the computational particle fluid dynamics (CPFD) approach. Furthermore, the effect of biomass feeding position is also comprehensively evaluated. The results show that for the co-combustion of coal and biomass, the O2 mole fraction at the furnace outlet rises from 0.0541 to 0.0640 as the biomass blending ratio enhances from 40% to 100%, while the CO2 mole fraction reduces from 0.1357 to 0.1267. The mole fraction of NOx and SO2 at the furnace outlet decreases from 4.5867 × 10−5 to 3.9096 × 10−5 and 2.8253 × 10−4 to 4.6635 × 10−5, respectively. For the tri-combustion of three fuels, the average NOx mole fraction initially grows quickly and then declines gradually, ranging from 4.1173 × 10−5 to 4.2556 × 10−5. The mole fraction of SO2 at the furnace outlet increases from 3.5176 × 10−4 to 4.7043 × 10−4 when the ratio of oil sludge rises from 10% to 20%. The uniformity of temperature and gas components distribution is "new inlet > secondary air inlet > feed inlet". As for the three inlet positions, the mole fractions of NOx at the furnace outlet are between 3.9096 × 10−5 and 5.1537 × 10−5, while those for SO2 are between 2.5978 × 10−4 and 2.5278 × 10−4. [ABSTRACT FROM AUTHOR]