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Inorganic sand cores involving sodium silicate binder and microsilica have environmental advantages during the casting process of aluminum alloy. Nevertheless, the bending strength of sodium silicate-bonded sand (SSBS) needs to be further improved. In this research, the effect of hydrophobic fumed silica on the bending strength of sand cores was studied. The experimental results revealed that hydrophobic fumed silica with the addition of 0.050 wt.% can be adopted as an optimal modifier to enhance the bending strength of SSBS. According to scanning electron microscope and spectroscopy techniques, dense bonding bridges and a complex Si–O–Si network containing specific silicon molecules with a silicon atom bonded to three other silicon atoms contribute to the excellent bending strength, with a 53.1% increase in cold strength (24 h) compared to a commercial sample of a modified sand core. Meanwhile, the newly formed Si–O–Al chemical bond plays a crucial role in increasing the bending strength of sand cores. [ABSTRACT FROM AUTHOR]

Climate warming has induced the thawing of permafrost, which increases the probability of thaw slump occurrences in permafrost regions of the Qinghai–Tibet Engineering Corridor (QTEC). As a key and important corridor, thaw slump distribution is widespread, but research into effectively using neural networks to predict thaw slumping remains insufficient. This study automated the identification of thaw slumps within the QTEC and investigated their environmental factors and susceptibility assessment. We applied a deep learning-based semantic segmentation method, combining U-Net with ResNet101, to high spatial and temporal resolution images captured by the Gaofen-1 images. This methodology enabled the automatic delineation of 455 thaw slumps within the corridor area, covering 40,800 km², with corresponding precision, recall, and F1 scores of 0.864, 0.847, and 0.856, respectively. Subsequently, employing a radial basis function neural network model on this inventory of thaw slumps, we investigated environmental factors that could precipitate the occurrence of thaw slumps and generated sensitivity maps of thaw slumps along the QTEC. The model demonstrated high accuracy, and the area under the curve (AUC) value of the receiver operating characteristic (ROC) curve reached 0.95. The findings of the study indicate that these thaw slumps are predominantly located on slopes with gradients of 1–18°, distributed across mid-elevation regions ranging from 4500 to 5500 m above sea level. Temperature and precipitation were identified as the predominant factors that influenced the distribution of thaw slumps. Approximately 30.75% of the QTEC area was found to fall within high to extremely high susceptibility zones. Moreover, validation processes confirmed that 82.75% of the thaw slump distribution was located within areas of high or higher sensitivity within the QTEC. [ABSTRACT FROM AUTHOR]

In drug discovery, selecting targeted molecules is crucial as the target could directly affect drug efficacy and the treatment outcomes. As a member of the CCN family, CTGF (also known as CCN2) is an essential regulator in the progression of various diseases, including fibrosis, cancer, neurological disorders, and eye diseases. Understanding the regulatory mechanisms of CTGF in different diseases may contribute to the discovery of novel drug candidates. Summarizing the CTGF-targeting and -inhibitory drugs is also beneficial for the analysis of the efficacy, applications, and limitations of these drugs in different disease models. Therefore, we reviewed the CTGF structure, the regulatory mechanisms in various diseases, and drug development in order to provide more references for future drug discovery. [ABSTRACT FROM AUTHOR]

In this study, the effect of adding different contents of yttrium (Y) during vacuum induction melting in Al2O3 and Y2O3 crucibles on the purification of DD5 alloys was investigated. The results show that the Y2O3 crucible exhibited great crucible stability and an excellent desulfurization effect when melting a Y-containing DD5 alloy. The S content of the alloy was reduced from 5.03 ppm to 1.36 ppm with the addition of 0.50 wt.% Y. Element Y combined with free S in the melt to form the YS phase, which was removed from the condensate shell and slag during the vacuum induction melting (VIM) process. Meanwhile, when the alloy was melted in the Y2O3 crucible with 0.50 wt.% Y addition, there was a reduction in S content from 2.77 ppm to 1.36 ppm compared to the Al2O3 crucible. Additionally, the loss of Y decreased from 0.12 wt.% to 0.05 wt.%. [ABSTRACT FROM AUTHOR]

The effect of La addition on primary α-Al and the eutectic Si phase of Al-7Si alloy is investigated systematically in this work. The results indicate that La addition causes a multi-refining efficiency on the microstructure of Al-7Si alloy, including refinement of α-Al grains and secondary dendrite arm spacing as well as eutectic Si particles. The grain size, secondary dendrite arm spacing and area of eutectic Si particles are decreased by 26.8%, 7.7% and 26.7%, respectively, with the addition of 0.1 wt.% La. It is also found that La-rich phases of Al2Si2La form and distribute in the vicinity of the eutectic Si phase. The crystal structure and lattice parameter of Al2Si2La phase are determined to be hexagonal (a = b = 0.405 nm, c = 6.944 nm) based on the TEM analysis results. The multi-refinement effects are mainly attributed to the increased constitutional undercooling caused by the low solubility of La in Al alloy and the growth-restricting factor caused by the Al2Si2La phase. [ABSTRACT FROM AUTHOR]

In this paper, an artificial neural network (ANN) model with high accuracy and good generalization ability was developed to predict and optimize the mechanical properties of Al–7Si alloys. The quantitative correlation formulas of the mechanical properties with Mg content and heat treatment parameters were established based on the transfer function and weight values. The relative importance of the input variables, Mg content and heat treatment parameters, on the mechanical properties of Al–7Si alloys were identified through sensitivity analysis. The results indicated that the mechanical properties of Al–7Si alloys were sensitive to Mg content and aging temperature. Then the individual and the combined influences of these input variables on the properties of Al–7Si alloys were simulated and the process parameters were optimized using the artificial neural network model. Finally, the proposed model was validated to be a robust tool in predicting the mechanical properties of the Al–7Si alloy by conducting experiments. [ABSTRACT FROM AUTHOR]

In this work, Y2O3 based composite crucibles with different Al2O3 contents were designed and characterized. The stability behaviors and interaction mechanisms between molten Ti-47Al-2Cr-2Nb alloy and Y2O3-Al2O3 composite crucibles were investigated at high temperature. Results showed that the surface morphology of crucibles and the degree of interfacial reactions between the composite crucibles and the metal melts varied with the change of Al2O3 content in the crucible matrix. The pure Y2O3 crucible was the densest and its chemical stability was the highest. With the increase in Al2O3 content, the number of pores on the crucibles surface gradually increased and the interfacial reactions between the composite crucibles and the molten alloys became weaker. When the content of Al2O3 in composite crucibles increased from 3.5 wt % to 10.5 wt %, the thickness of the interface layer of melt-crucible decreased from 150 µm to 50 µm, and the equilibrium contact angles between metal and crucibles gradually decreased from 69.3° to 64.2° at 1873 K. [ABSTRACT FROM AUTHOR]

To obtain appropriate crucible materials for vacuum induction melting of MCrAlY alloys, four different oxide ceramics, including MgO, Y2O3, Al2O3, and ZrO2, with various microstructures were designed and characterized. The high-temperature wettability and interactions between Ni-20Co-20Cr-10Al-1.5Y alloys and oxide ceramics were studied by sessile drop experiments under vacuum. The results showed that all the systems exhibited non-wetting behavior. The contact angles were stable during the melting process of alloys and the equilibrium contact angles were 140° (MgO), 148° (Y2O3), 154° (Al2O3), and 157° (ZrO2), respectively. The interfacial reaction between the ceramic substrates and alloys occurred at high temperature. Though the ceramics had different microstructures, similar continuous Y2O3 reaction layer with thicknesses of about 25 μm at the alloy-ceramic interface in MgO, Al2O3, and ZrO2 systems formed. The average area percentage of oxides in the alloy matrices were 0.59% (MgO), 0.11% (Al2O3), 0.09% (ZrO2), and 0.02% (Y2O3), respectively. The alloys, after reacting with MgO ceramic, had the highest inclusion content, while those with the lowest content were in the Y2O3 system. Y2O3 ceramic was the most beneficial for vacuum induction melting of high-purity Y-containing Ni-based alloys. [ABSTRACT FROM AUTHOR]