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121.
Xin Liang Li Li Yan Dong Wei Dong Hongxia Cui Chunhui Xia Tao Xu Chaozhong Wang Jie Zhang Tingting Liu Huimin Sui Chao Gao 《Molecules (Basel, Switzerland)》2022,27(9)
Estrogens added illegally to dietary supplements are hazardous to human health. Traditional detection and analysis methods have many limitations, and we have developed an assay that combines thin-layer chromatography with Raman imaging microscopy (TLC-RIM). The five estrogens (estrone, estradiol, estriol, ethinyl estradiol, and diethylstilbestrol) were initially separated by TLC, then detected by area scanning Raman imaging with a 532 nm laser under a microscope. Raman spectra were obtained for each estrogen, which were used for detecting estrogen illegally added to botanical dietary supplements. The LOD of each estrogen was 0.4, 1.0, 0.8, 0.2, and 0.2 mg/mL, respectively. The matrix in the real sample did not interfere with the detection of estrogens. The method was fast, sensitive, stable, specific, and reliable. 相似文献
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We report on our study of the interactions between coconut protein extracted from coconut meat and three hydrocolloids (gelatin, xanthan gum, and soybean polysaccharide) and their interfacial adsorption and emulsification properties. We used Zeta potential, fluorescence spectroscopy scanning and ITC to investigate the interactions between a fixed concentration (1%) of coconut protein and varying concentrations of hydrocolloid. Through the interfacial tension and interfacial viscoelasticity, the interfacial properties of the hydrocolloid and coconut protein composite solution were explored. The physical stability of the corresponding emulsion is predicted through microstructure and stability analysis. Xanthan gum forms a flocculent complex with coconut protein under acidic conditions. Soy polysaccharides specifically bind to coconut protein. Under acidic conditions, this complex is stabilized through the steric hindrance of soy polysaccharides. Due to gelatin-coconut protein interactions, the isoelectric point of this complex changes. The interfacial tension results show that as time increases, the interfacial tensions of the three composite solutions decrease. The increase in the concentration of xanthan gum makes the interfacial tension decrease first and then increase. The addition of soybean polysaccharides reduces the interfacial tension of coconut protein. The addition of xanthan gum forms a stronger elastic interface film. Emulsion characterization showed that the gelatin-added system showed better stability. However, the addition of xanthan gum caused stratification quickly, and the addition of soybean polysaccharides also led to instability because the addition of polysaccharides led to a decrease in thermodynamic compatibility. This research lays the foundation for future research into coconut milk production technology. 相似文献
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文章分析了传统ERP系统存在的问题,针对系统智能性、可重构性差等缺点,基于"软件人"、多库协同等技术提出了"分布式智能ERP系统"的体系结构模型,为系统的设计和应用提供了基础. 相似文献
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如何有效规制技术巨头已然成为当前《反垄断法》修订的重要任务。技术力量虽然作为传统的市场支配地位认定要素,但长期以来呈现被虚置化的客观状态,致使技术巨头市场支配地位的认定难度增大,技术力量自身的传导效应被显著低估。数字技术对市场竞争的影响异于以往,其通过平台、数据、算法的数字市场三维结构框架影响生产与交易的全过程。技术与三维结构结合所形成的技术力量极为强大,超越了以控制价格为主的传统市场力量,结合社会与资本力量形成了更牢固的市场固化结构。在判断技术巨头的市场支配地位时,亟需发挥技术力量作为非价格型认定要素的重要作用。应当摒弃虚置技术力量作为市场支配地位认定要素的固有症结,提高技术力量在认定市场支配地位时所占权重,回归结构性视角,妥善防范技术巨头无序扩张。 相似文献
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