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Lysophosphatidylcholine (LPC) possesses excellent oil‐in‐water emulsifying properties and health benefits. The objective of this study was to produce an LPC‐enriched fraction from lysolecithin generated during enzymatic degumming of crude canola oil. Three alcohols (methanol, ethanol and isopropanol) were evaluated for their effectiveness at enriching LPC. A 3 × 3 full factorial design was employed to study the effects of two processing parameters (temperature and alcohol/lysolecithin ratio) on three responses (yield and LPC concentration of alcohol soluble fraction, and LPC recovery) with the most effective alcohol. Ethanol was found to be the best solvent to enrich LPC in lysolecithin. An ethanol soluble fraction with more than 50 % LPC was produced. Quadratic models with R2 > 0.9 were developed to describe the relationship between the processing parameters and the responses in the 3 × 3 full factorial experiment. Both ethanol soluble fraction yield and LPC recovery increased with increasing temperature and ethanol/lysolecithin ratio. LPC concentration in the ethanol soluble fraction was enhanced with decreasing temperature and ethanol/lysolecithin ratio. According to the analysis, ethanol soluble fractions with LPC concentration higher than 66 % could be obtained at temperatures of 0–40 °C and an ethanol/lysolecithin ratio of 2:1 (v/w).  相似文献   
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This study introduces a comprehensive framework designed for detecting and mitigating fake and potentially threatening user communities within 5G social networks. Leveraging geo-location data, community trust dynamics, and AI-driven community detection algorithms, this framework aims to pinpoint users posing potential harm. Including an artificial control model facilitates the selection of suitable community detection algorithms, coupled with a trust-based strategy to effectively identify and filter potential attackers. A distinctive feature of this framework lies in its ability to consider attributes that prove challenging for malicious users to emulate, such as the established trust within the community, geographical location, and adaptability to diverse attack scenarios. To validate its efficacy, we illustrate the framework using synthetic social network data, demonstrating its ability to distinguish potential malicious users from trustworthy ones.  相似文献   
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In this study, polyvinyl alcohol (PVA) and boric acid (BA) were mixed in an aqueous medium by heating in order to prepare a PVA/BA hybrid material. The viscosity and pH values of the PVA/BA hybrid material mixed in various proportions were determined. Then the hybrid polymer was electrospun to give dimensions to fibers. The FT-IR spectra of these fibers revealed that BA chemically reacted with PVA and formed B–O–C bonds. The fibers were first calcified at 500 °C and then the calcified products were pelleted and exposed to the sintering process at 1300 °C. The XRD peaks of the sintered product were seen at 2θ = 34.7 and 37.7° verified the formation of boron carbide. The study proved that it was possible to use sub-micron fibers for the production of sub-micron boron carbide material.  相似文献   
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In this study, boron doped and undoped poly (vinyl) alcohol/bismuth–gadolina acetate (PVA/Bi–Gd) nanofibers were prepared using electrospinning technique then calcinated at 800 °C for 2 h. The originality of this study is the addition of boron to metal acetates. The effects of boron doping were investigated in terms of solution properties, morphological changes and thermal characteristics. The characteristics of the fibers were investigated with FT-IR, XRD, SEM and BET. The addition of boron did not only increase the thermal stability of the fibers, but also their diameters, which yielded stronger fibers. XRD analyses showed that boron doping increased the peak intensities and indicated that the boron doping enhanced the crystallite size. Moreover, no shifts were noticed in diffraction angles for boron doped and undoped samples. Therefore, boron doping did not significantly alter the lattice spacing. The SEM micrograph of the fibers showed that the addition of boron resulted in the formation of cross-linked bright-surfaced fibers. The average fiber diameter for boron doped and undoped fiber mats were 204 and 123 nm, respectively. Also, grain diameters of boron doped and undoped nanocrystalline sintered powders were measured as 140 and 118 nm, respectively. The BET results showed that boron undoped and doped Bi2O3–La2O3 nanocrystalline powder ceramic structures sintered at 800 °C have surface areas of 59.72 and 39.80 m2/g, respectively.  相似文献   
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