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Abstract: In this study, KMgF3:Eu2+ luminescent nanocrystals (NCs) were prepared in water/cetyltrimethylammonium bromide (CTAB)/2-octanol microemulsions. The KMgF3:Eu2+ NCs were characterized by transmission electron microscopy (TEM), X-ray diffractometer (XRD), fluorescence spectrum, infrared spectroscopy (IR) and elementary analysis. The results showed that the size of the KMgF3:Eu2+ NCs was hardly affected by water content and surfactant (CTAB) concentration. The emission spectrum showed that the position of the 362nm peak is due to the K+ sites substituted Eu2+. Two emission peaks located at 589 and 612nm can be attributed to Eu3+, which exist at two different types of Eu3+ centers: one is Eu3+ at a K+ site, the other is clustering of Eu3+ ions in the interstices of KMgF3 host lattice. [Copyright &y& Elsevier]

The different ions doped KMgF3 single crystals are prepared by the vertical Bridgman method. The near-infrared absorption spectra for different parts of all as-growth crystals indicate that there is the best transparency in middle part. The correlation between the vibronic frequencies of Eu2+ and the site displacement of Cu+ co-doped ions is firstly studied, which indicates that Cu+ ions replace the site of the Mg2+ ions. The co-doped Eu2+ counteracts the charge misfit causing by the replacement of Mg2+ with Cu+. The overlapping of the emission spectra of the Eu2+ and the excitation spectra of the Cu+ results in the energy transfer from Eu2+ to Cu+. [Copyright &y& Elsevier]

The complex fluorides KMgF3 and KZnF3 with Perovskite structures were solvothermally synthesised at 150–180°C and characterised by means of X-ray powder diffraction, scanning electron microscopy, thermogravimetric analysis and infrared spectroscopy. [Copyright &y& Elsevier]

The precipitation behavior of a typical Si-rich low Cu Al-Mg-Si-Cu alloy (AA6022 alloy) was thoroughly investigated by atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), atom probe tomography (APT) and first-principles calculations. It was revealed that the slight Cu addition significantly alters the precipitate sequence of the Al-Mg-Si alloy, resulting in a distinct sequence compared with the Cu-free and high Cu alloys. Low amounts of Cu are incorporated in the clusters and the β″ phase in the under- and peak-aged stages. During over-aging, fragmentation and hybridization of different unit cells or substructures linked to the intermediate stage of the β″ → B′/Q′ transformation is observed. The B′/Q′ composite precipitate is shown to be the dominant precipitate in the over-aged condition, while other precipitates, i.e., β', U1 and U2, commonly displayed in the Si-rich Cu-free alloys, are suppressed. During subsequent aging, a B′/Q composite precipitate with a core-shell structure is formed due to the segregation of Cu atoms at the precipitate/matrix interface. The Cu segregation is shown to be beneficial for stabilizing the precipitate interface structure. The proposed altered precipitation reaction of the Si-rich low Cu Al-Mg-Si-Cu alloy is: SSSS → atomic clusters → GP zones → β″ → B′/Q′ → B′/Q + Si. [Display omitted] • The β', U1 and U2 phases are suppressed after slight addition of Cu. • The B′/Q′ composite precipitate is the dominant precipitate formed in over-aged stage. • An altered precipitation reaction of the Si-rich low Cu Al-Mg-Si-Cu alloy is proposed. [ABSTRACT FROM AUTHOR]

The effects of pre-straining on the precipitation behavior and mechanical properties of a series of Al–Mg–Si–Cu alloys with different Mg/Si ratios and Cu addition were systematically investigated by hardness measurement, tensile testing, scanning electron microscopy (SEM) imaging and atomic resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging. Regardless of alloy composition, pre-straining can effectively accelerate the precipitation kinetics of the alloys. However, the effect on the age hardening response is highly dependent on alloy composition. Pre-straining can effectively promote the age hardening response of the Si-rich alloys, with Cu addition further enhancing the effect. For the Mg-rich low Cu alloy, the age hardening is detrimentally affected by pre-straining, and only compensated to some extent by Cu addition. The branched effect of pre-straining may be linked to the different precipitation reactions of the alloys. Due to the accelerated precipitation kinetics induced by dislocations, the presence of clusters with different sizes or densities, linked to a changed alloy composition, can evolve into notably different precipitate microstructures. In addition, heterogeneous precipitation at the dislocations can result in the formation of various string-like post-β″ precipitates (such as B′, Q′, β′, QP2 phases), which produce distinct strengthening potentials. This work suggests that the alloy composition, especially the Mg/Si ratio and Cu content, would have to be fully taken account when designing a pre-straining process. [ABSTRACT FROM AUTHOR]

Effect of homogenization and warm-rolling on the mechanical properties of Al-11.38Zn-2.45Mg-1.1Cu-0.13Zr-0.1Fe (wt. %) alloy fabricated by spray forming technology was studied by scanning electron microscopy (SEM), electron back-scatter diffraction (EBSD), X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The results indicate that the combination of homogenization and warm-rolling exhibit significantly potential for increasing the mechanical properties of the spray formed alloy. The introduction of two-step homogenization process can promote the precipitation of substantial amount of Al 3 Zr dispersoids, which provide the Orowan strengthening and inhibit recrystallization of the alloy. The warm-rolling at 200 °C produces a large number of dislocations, which not only provide strain hardening, but also promote the precipitation of η' phase during aging treatment. Besides, the relatively low temperature rolling combined with Al 3 Zr dispersoids can avoid dynamic recrystallization and thus maintain fibrous microstructure of the alloy. An ultrahigh strength (YS = 868.9 ± 1.6 MPa, UTS = 878.6 ± 2.8 MPa, respectively) is achieved for the alloy due to synergistic effect of homogenization and warm-rolling. [ABSTRACT FROM AUTHOR]

The present work aims to reveal the dispersoids evolution and the valuable role of Zr on the elevated-temperature creep resistance of Al–7Si-0.3Mg alloy. At 300°C and 25 MPa, Al–7Si-0.3Mg-0.15Zr alloy exhibits more than double decrement in the minimum creep rate, and 263 h increment in creep time-to-fracture compared to the Zr-free cast alloy. These effects were owe to the formation of novel nanobelt-like Si 2 Zr and rectangle-like (Al, Si) 3 –Zr dispersoids during solutionising at 560°C for 20 h. The Si atoms could substitute for Al sites to form stable L1 2 -Al 2 Si 1 Zr structure. The thermally stable dispersoids were semi-coherent/coherent with the Al matrix, which impeded the movement of dislocations during creep deformation at 300°C. It demonstrated that the superior creep resistance (300°C) achieved in the Al–7Si-0.3Mg-0.16Zr alloy was attributed to the introduction of novel Zr-containing dispersoids. [ABSTRACT FROM AUTHOR]

• In addition can suppress the negative effect of NA and improve precipitation during AA for Al-Mg-Si alloys. • In atoms incorporate into clusters and facilitate their transformation to β′′ phase at the early AA. • In atoms segregate at the β′′/α-Al and β′/α-Al interfaces by replacing the Si atoms or Al atoms. • In-rich particles are formed at the edge of the β′ phase or in the α-Al matrix. [Display omitted] The impact of In addition on the precipitation behavior and properties for Al-Mg-Si alloys under different aging treatments was systematically studied by hardness measurements, atom probe tomography (APT), high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and density functional theory (DFT) calculations. We found that the In addition effectively suppresses the harmful effect of natural aging (NA), and improves the age hardening for the Al-Mg-Si alloy. Mg-Si-In clusters are formed in the early stage of aging caused by the incorporation of In atoms, which can facilitate the nucleation of the β" phase. During peak aging, In atoms distort the well-ordered structure of the β" and occupy the positions in the interface of the β", facilitating the transition of β" to post-β" (i.e., U2 and β′). During the following aging, In atoms are presented in two different configurations: forming In-rich particles and aggregation at the interfaces of β′. Most of the In-rich particles are formed at the edge of the β′ particles. The segregation of In atoms at the precipitate/matrix interface and the formation of In-rich particles can probably be attributed to the reduced strain energy of the β′ phase it brings about. [ABSTRACT FROM AUTHOR]

The addition of Sn in Al-Mg-Si alloys has drawn widely attention due to its strong interaction with the vacancies. In the present work, the effect of different amount of Sn addition on natural aging and precipitation hardening in Al-Mg-Si alloys are investigated. During natural aging (NA), the Sn addition can effectively suppress the clustering by capturing vacancies, and the NA hardness is gradually decreased with increasing Sn content. However, during artificial aging (AA) at 170 °C after NA, it is found that the positive effect of Sn addition is highly dependent on the Sn content. A Sn content ≤0.1 wt% can facilitate the precipitation of β″ phase due to the release of vacancies at high aging temperature. While a Sn content >0.1 wt% can result in a decrease of AA hardness. This is mainly due to the coarser and sparser distribution of β″ phases in the α-Al matrix. Besides, the excess Sn atoms preferentially form coarse primary Sn particles and Mg 2 Sn particles instead of being solute atoms in the α-Al matrix, which can deteriorate the mechanical properties of this alloy. Some Sn particles are formed at the interface of Fe-rich intermetallic particle, which probably refine the Fe-intermetallic phases in the high-Sn alloys. These results indicate that the Sn content should be accurately controlled for the Al-Mg-Si-Sn alloys with increased properties. • The positive effect of Sn addition for the Al-Mg-Si alloy highly depends on the Sn content. • A Sn content ≤0.1 wt% can facilitate the precipitation of β″ phase during AA after NA and the 0.1 wt% Sn added alloy exhibits highest peak hardness. • Sn content ≥0.2 wt% can suppress the precipitation due to the formation of coarse primary Sn particles and Mg 2 Sn particles. [ABSTRACT FROM AUTHOR]

Complicated plastic deformation and welding temperature were generated in the nugget zone (NZ) of friction stir welding (FSW) joints leading to different regions being developed, such as shoulder influence zone (SIZ), pin influence zone (PIZ) and swirl zone (SZ). To find the effect of rotation speed on microstructure evolution and mechanical properties of these regions during friction stir welding, serials of AA2195-T8 plates with 7.5 mm thickness were fabricated using different rotation speeds (500, 700 and 900 rpm) and a constant welding speed (50 mm/min). Microstructural characterization was conducted out using electron back scattered diffraction (EBSD), differential scanning calorimetry (DSC), transmission electron microscopy (TEM) and X-ray diffraction (XRD) technologies. Mechanical properties were measured by micro-hardness and tensile test. The results show that grains in the SIZ were mainly shown in wedge-shaped structure and had the high density of low angle boundaries (LABs) showing dominant (100) orientation. However, in the PIZ and SZ, fine and equiaxed grains with dominant (111,101) orientation were observed. With rotation speed increasing, the fraction of LABs increased in the SIZ but showed little changes in the PIZ and SZ. After welding, a large number of T 1 and θ′ precipitates almost be completely dissolved in the NZ with many fine δ′/β′ being re-precipitated. It is notable that a few T 1 precipitates were observed in the SIZ at a higher rotation speed (900 rpm), which were re-precipitated from the Al matrix after dissolution. In the SIZ, the dominant contribution to yield strength was dislocation strengthening which enhanced with rotation speed increasing. However, in the PIZ and SZ, grain refinement strengthening was the primary strength mechanism, which decreased with rotation speed increasing. • Systematic study about the effects of rotation speed on microstructure evolution and mechanical properties of different regions in nugget zone of 2195 aluminum alloy friction stir welding joints was conducted. • The precipitation mechanism of the T 1 phase in the nugget zone was analyzed. • Strengthening mechanism of the NZ was discussed in detail. [ABSTRACT FROM AUTHOR]

In this paper, four model Al–Mg–Si automotive sheet alloys with different Mg and Si contents were prepared and heated treated to the same T4P temper (solution treated and pre-aged for 8 h at 75 °C and aged for 1 week at room temperature). The influence of the Mg and Si content on microstructure, crystallographic texture, tensile behavior and bendability was investigated. The evolution of microstructure and texture during thermomechanical processing was characterized. It was found that the bendability of sheets in the T4P temper decreases with raising Mg and Si content. The deterioration of bendability can be related to the decreased true fracture strain measured in tension. The fracture mode in the bend tests was found to be predominately transgranular. Crack initiation was observed at α-Al(FeMn)Si constituent particles and the propagation of cracks proceeded by a combination of shear bands and void growth/coalescence. Finally, the strength of the recrystallization texture increases was observed to increase with increasing Mg and Si contents and it was found that the relationship between crystallographic texture and the plastic anisotropy, e.g. r-value, could be predicted using the visco-plastic self-consistent (VPSC) polycrystal plasticity model. • The bendability of Al–Mg–Si alloys sheets after solution treatment decreases with raising Mg and Si contents. • The transgranular fracture mode is mainly account for the bending of Al–Mg–Si alloys sheets in T4P temper. • Cracks initiate at α-Al(FeMn)Si constituent particles and propagate by a combination of shear bands and void growth. [ABSTRACT FROM AUTHOR]

In this study, the effects of pre-aging and natural aging on the clusters, strength and hemming performance of AA6014 Al–Mg–Si alloys with different Mg/Si ratios were investigated through three-dimensional atom probe (3DAP) in combination with tensile test and three-point bend test. Samples are subjected to natural aging (room temperature, ~25 °C) or pre-aging (elevated temperature, 75 °C) treatments in order to generate different types of clusters. The number density, size and compositions of clusters are analyzed by 3DAP. The increased strength and deteriorated hemming performance are found in natural aged alloys, especially for Si-rich alloy. The hemmability is sensitive to the strength, and an increased strength leads to inferior hemmability. The formation of Mg 1 Si 1 type cluster is encouraged during pre-aging treatment regardless of the alloy composition. Natural aging following directly water quenching promotes the formation of a large number density of small-sized Si-rich clusters in Si-rich alloy, whereas relatively low density of clusters with scattered Mg/Si ratios distribution in Mg-rich alloy. The concentration of the excess vacancies and the binding energy between vacancy and Mg and Si atoms plays an important role in the precipitation kinetics of cluster during different aging processes. Finally, the clusters and solid solution atoms statistics are utilized to predict the yield strength of the alloys in different aging conditions. [ABSTRACT FROM AUTHOR]

Esophageal cancer is a major global health challenge with a poor prognosis. Recent studies underscore the extracellular matrix (ECM) role in cancer progression, but the full impact of ECM-related genes on patient outcomes remains unclear. Our study utilized next-generation sequencing and clinical data from esophageal cancer patients provided by The Cancer Genome Atlas, employing the R package in RStudio for computational analysis. This analysis identified significant associations between patient survival and various ECM-related genes, including IBSP, LINGO4, COL26A1, MMP12, KLK4, RTBDN, TENM1, GDF15, and RUNX1. Consequently, we developed a prognostic model to predict patient outcomes, which demonstrated clear survival differences between high-risk and low-risk patient groups. Our comprehensive review encompassed clinical correlations, biological pathways, and variations in immune response among these risk categories. We also constructed a nomogram integrating clinical information with risk assessment. Focusing on the TENM1 gene, we found it significantly impacts immune response, showing a positive correlation with T helper cells, NK cells, and CD8+ T cells, but a negative correlation with neutrophils and Th17 cells. Gene Set Enrichment Analysis revealed enhanced pathways related to pancreatic beta cells, spermatogenesis, apical junctions, and muscle formation in patients with high TENM1 expression. This research provides new insights into the role of ECM genes in esophageal cancer and informs future research directions., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this article., (Copyright © 2024 Yinghong Wu et al.)

This study aims to evaluate the prognostic significance of thyroid function-related indices in patients with differentiated thyroid cancer (DTC). This retrospective analysis included 90 patients diagnosed with DTC and treated at our hospital from January 2010 to January 2019. Patients were classified into 2 groups based on whole-body imaging results: 67 with a favorable prognosis and 23 with a poor prognosis. The study compared clinical data and thyroid function indices between these groups to assess their efficacy in prognostic prediction. Patients in the poor prognosis group had a higher occurrence of T3-4 stage cancer (P = .006) and ≥2 lymph node metastases (P = .019). Notably, levels of total thyroxine (TT4), thyroid-stimulating hormone (TSH), and thyroglobulin antibody (Tg-Ab) were significantly elevated in this group (P < .001 for each). Receiver operating characteristic analysis revealed substantial predictive accuracy for TT4, TSH, and Tg-Ab (area under curve of 0.747, 0.820, and 0.720, respectively). The columnar graphical model used for prediction demonstrated a high concordance index (C-index = 0.919), superior to single-indicator evaluations. Thyroid function indices, specifically TT4, TSH, and Tg-Ab, play a crucial role in the prognostic assessment of patients with DTC. The column-line diagram model effectively enhances prophetic prediction, aiding in clinical decision-making., Competing Interests: The authors have no funding and conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

The morphology, composition, and structure of precipitates in an Al-Si-Mg-Hf alloy after heat treatment at 560°C for 20 h were studied by means of C s -corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), energy dispersive X-ray spectrometry (EDS), high-resolution transmission electron microscopy (HRTEM), and first-principle calculations. Precipitates with three kinds of morphologies were observed. The rectangular and square precipitates were predominantly (Si2-x Al x )Hf phases, while the nanobelt-like precipitate is the Si2Hf phase. First-principle calculations were used to show that the Si6 and Si8 sites were the most favorable sites for Al incorporation in the orthorhombic Si2Hf phase.

With greenhouse plastic film, rice straw plus greenhouse plastic film, soil-mulching plastic film, rice straw, rice straw plus sun-shading net, and sun-shading net as test mulches, this paper studied their effects on the rhizosphere temperature, growth, and physiological properties of flue-cured tobacco. The results showed that after mulching for 22 days, the accumulative rhizosphere temperature at the depth of 5 cm was the highest (424.75 degrees C) for greenhouse plastic film and the lowest (378.75 degrees C) for rice straw plus sun-shading net, while that at the depth of 15 cm was the highest (396.75 degrees C) for greenhouse plastic film and the lowest (368.31 degrees C) for sun-shading net. With the increase of accumulative rhizosphere temperature, the dry weight of above- and underground parts, photosynthesis, and root vigor of flue-cured tobacco tended to increase, and at the 10th day after mulches removal, root biomass had the largest increment in the treatment of soil-mulching plastic film and the smallest increment in the treatment of rice straw plus sun-shading net.

Aromatic/aliphatic copolyesters containing hydrophilic moieties in the main chain or side chain were synthesized by bulk polycondensation of aromatic monomers without or with solubilizing substituents and aliphatic monomers. Hydrolytic and enzymatic degradation studies were carried out in vitro at 37 degrees C in pH 7.4 phosphate buffer and in Tris-HCl buffer containing proteinase K. The results indicate that liquid-crystalline aromatic/aliphatic copolyesters are degradable hydrolytically as well as enzymatically. The change in composition and morphology of the polyester films were monitored by nuclear magnetic resonance and scanning electron microscopy. The results suggested that aromatic species and aliphatic moieties could be released into aqueous solution during hydrolytic degradation of aromatic/aliphatic copolyesters with ethyleneoxy groups on the side chain. Modifying aromatic species with hydrophilic groups in aromatic/aliphatic copolyesters was an efficient method to improve degradability and biocompatibility due to improved solubility of degradation products in aqueous solution. Mechanical tests indicated that the copolyesters exhibited good mechanical properties prior to degradation, which can be of relevance for bone tissue engineering.