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A purification process including flotation separation, acid leaching, calcination, and water quenching was conducted to obtain high-purity quartz sand. The surface morphology of the quartz after flotation separation, acid leaching, calcination, and water quenching reveals that the cracks, pits, and cavities on the quartz surface can be deepened and enlarged, and the more fluid inclusions, the greater the number and openness of cracks, pits, and cavities. The specific surface area is positively correlated with the number of cracks, pits, and cavities, the opacity of quartz glass, and the number of bubbles in quartz glass. The results of Raman spectroscopy analysis reveal that the bubbles in quartz glass are composed of nitrogen, which excludes the possibility of bubble formation in quartz glass caused by the gas composition (i.e., H2O) of unburst fluid inclusions in quartz sand. The formation of bubbles in quartz glass is more likely to be related to a high specific surface area and porosity, which increase the surface adsorption performance of quartz and contribute to the adsorption of more gas. The presented results suggest that using these methods to reduce the content of fluid inclusions in quartz cannot effectively solve the problem of bubbles in quartz glass, and using quartz raw materials with no or minor fluid inclusions is still the key to ensuring the quality of quartz products. [ABSTRACT FROM AUTHOR]

The regulation of fruit development is a complex process and a core issue in the fruit tree industry. To investigate the role of PbGIF1 in pear fruit development, we identified a transcription factor PbbHLH137 that regulates pear (Pyrus bretschneideri) fruit development by screening a yeast library constructed from fruit cDNA. Yeast two‐hybrid (Y2H), bimolecular fluorescence complementation (BiFC), and split luciferase complementation (split‐LUC) assays were performed to confirm the PbbHLH137–PbGIF1 interaction. By tracing the complete fruit development process, we found that PbbHLH137 expression was closely related to fruit size and highly involved at the late pear fruit development stage. Transgenic experiments showed that heterologous expression of PbbHLH137 or PbGIF1 promoted fruit enlargement. PbbHLH137 promoted mainly the expansion of fruit cell volume, whereas PbGIF1 mainly increased the number of cells. Further LUC experiments demonstrated that PbGIF1 promoted the transcriptional activation ability of PbbHLH137. Our work identified PbbHLH137 as a transcription factor that regulates fruit development, and showed that PbGIF1 played an ongoing role during fruit development, making it a candidate gene for genetic improvement of pear fruit development. [ABSTRACT FROM AUTHOR]

Disposable PVC gloves are cost effective, but their mechanical properties can be compromised at extremely high concentrations of plasticizers. The tensile properties of PVC gloves can be improved by incorporating modified fillers into the PVC matrix. In this research, calcium carbonate (CaCO3) was functionalized with γ‐methacryloxy propyl trimethoxyl silane (KH‐570) and then further modified through a click reaction with n‐Octadecyl mercaptan. Fourier‐transform infrared spectroscopy and X‐ray photoelectron spectroscopy have confirmed that n‐Octadecyl mercaptan‐modified KH‐570 was successfully grafted onto the surface of CaCO3. Composite films were manufactured by blending either pristine CaCO3 or modified CaCO3 with PVC resin paste and their tensile properties, light transmission, moisture permeability, and solvent resistance were evaluated. Compared with CaCO3/PVC and KH‐570‐modified CaCO3/PVC composite films, n‐Octadecyl mercaptan‐modified CaCO3/PVC composite films showed higher light transmittance, lower moisture permeability, and higher tensile properties. Dynamic mechanical analysis revealed that these films had low glass transition temperatures, thus broadening their applicability to low‐temperature conditions. [ABSTRACT FROM AUTHOR]

The modified cyanate ester resin(CE) which can be applied stably in the cryogenic environment was prepared by using phenoxy resin(PKHH) and high purity epoxy resin(EP) through the method of melting prepolymerization. The results show that the curing reaction of CE is accelerated by the addition of PKHH, but the reaction pathways are not changed. It is found that PKHH can improve the ductility by the mechanism of the semi-interpenetrating network (SIPN) in the cured CE networks. Especially, the impact strength value of the CE/EP blends with the content of 10% (mass fraction) PKHH reaches to 18.4 kJ/m2 and the modulus is maintained at about 3.5 GPa at –196 ℃, accordingly the cracks are not observed on the surface of specimens after 20 low-high temperature cycles (–196 to 200 ℃).