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61.
Junjun Liu Wenbin Zhang Pengfei Li Zhumao Jiang Ruijin Yang 《International Journal of Food Science & Technology》2020,55(9):3203-3214
A two-stage microfiltration and ultrafiltration (MF/UF) for peanut protein recovery and water recycling from aqueous extraction processing (AEP) were investigated. Peanut protein aggregates and alkaline water were obtained using flat and wound MF/UF and alkaline water recycled in AEP. With this approach, most of the wastewater could be recycled to produce reusable water to solve wastewater problems in aqueous oil extraction processing from oilseeds. The result showed that a little oil and protein were lost (1.21% and 4.35%, respectively) during the recycling of permeate in AEP, which was still acceptable. Peanut protein aggregations (PPAs) were characterised by analysis with Fourier-transform infrared spectroscopy (FTIR), sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE), high-performance gel filtration chromatography (HPGFC) and binding force analysis. Solubility analysis suggested that PPA had molecular structures with more hydrophobic groups on the surface than in the peanut protein isolate (PPI). In vitro, PPA was digested by both pepsin and trypsin more than PPI. FTIR profiles demonstrated there were more β-sheet and less α-helix in PPA, which means much more aggregation. In addition, binding force analysis showed hydrophobic interaction was the major force that restricted dissolution of PPA and disulfide bonds were of second importance, which provided a possible physical treatment opportunity for improving the solubility of PPA. 相似文献
62.
采用连续离子交换技术用于盐湖卤水的吸附法提锂。针对青海一里坪盐湖老卤体系,开发了连续离子交换吸附提锂工艺,研究了操作参数对连续离子交换系统提锂性能的影响,并在优化的工艺条件下进行了长周期的稳定性评价。结果表明,在转动步进周期为20 min、卤水进料量为3.2 BV/h、淋洗水量为2.9 BV/h、解吸水量为9.3 BV/h、解吸温度为15~25 ℃时,连续离子交换系统可以稳定获得镁锂质量浓度比(简称镁锂比)在3左右、锂质量浓度接近1.1 g/L的合格液,锂回收率为98.5%以上。 相似文献
63.
湿法磷酸制备磷酸脲过程中会副产大量磷酸脲母液,母液含有金属杂质及五氧化二磷含量较高。采用溶剂萃取法回收磷酸脲母液中五氧化二磷制备工业级磷酸二氢铵(MAP),分别考察了包括萃取、洗涤、中和、精制、结晶等工艺流程对产品收率及纯度的影响,确定了最佳工艺条件:萃取相比(有机相与水相体积比)=3:1,萃取时间为5 min,萃取温度为50 ℃,洗涤相比(有机相与洗涤剂体积比)=10:1,中和pH为4.5,复合酸性萃取剂PO8皂化率为20%,精制相比(萃取剂与水相体积比)=1:1,浓缩比为1.36,结晶温度为30 ℃。在该条件下制备的工业级MAP纯度可达99.45%,母液中五氧化二磷回收率为85.34%。该工艺对环境友好,原料中五氧化二磷回收率高,具有较高的经济效益。 相似文献
64.
采用1-乙烯基-3-正丁基溴代咪唑离子液体([VBIM]Br)为脱除剂,在β-环糊精协同作用下萃取溶剂油中的萘。本实验考察了不同单因素条件在[VBIM]Br离子液体与β-环糊精共同作用下对溶剂油中脱萘率的影响,同时通过响应面法优化脱除工艺条件。实验结果表明:[VBIM]Br离子液体与β-环糊精共同作用下对萘的萃取率比单独利用[VBIM]Br离子液体提高了15%以上,萃取率达到90%以上。离子液体简单回收后,重复使用5次过后,脱除率仍在80%以上。实验通过红外分析和紫外光谱分析了[VBIM]Br离子液体协同β-环糊精脱萘的机理,与[VBIM]Br离子液体协同作用下,β-环糊精对萘存在包合作用,实现了对溶剂油中萘的脱除。 相似文献
65.
为解决蒋家河煤矿采空区瓦斯涌出量大、上隅角瓦斯超限和回风平巷风排瓦斯量大等问题,提出了本煤层预抽、专用瓦斯抽放巷抽采和上隅角埋管抽采瓦斯相结合的方法对该矿ZF202综放工作面进行瓦斯治理,进行了现场实测和瓦斯抽采效果分析。结果表明,本煤层预抽后,瓦斯含量由7.92 m^3/t下降为4.21 m^3/t,瓦斯压力由0.72 MPa下降为0.38 MPa;上隅角瓦斯浓度由0.78%下降至0.4%左右。通过对比,专用瓦斯抽放巷的抽采纯量是高位钻孔的2.5倍,抽采效果好于高位钻孔,使工作面和上隅角瓦斯浓度保持较低水平,有效地解决了特厚煤层综放工作面瓦斯超限问题,为安全生产提供了重要保障。 相似文献
66.
大多数现有的主流结构光测量装置在被测物体的表面上投射单条激光,通过移动装置实现物体表面的扫描重建。为了实现物体表面的在线快速重建,将多线结构光和双目立体视觉理论相结合,设计了一种新的三维测量方法。提出了一种结合形态滤波和Zhang-Suen细化算法的光条骨架提取方法和基于光条序列关系的光条匹配算法,并通过极线约束实现光条上特征点的精确匹配。通过实验验证了方法的有效性,相对误差在3%以内。 相似文献
67.
Susan Sabra Khalid Mahmood Malik Muhammad Afzal Vian Sabeeh Ahmad Charaf Eddine 《Expert Systems》2020,37(1):e12388
Clinical narratives such as progress summaries, lab reports, surgical reports, and other narrative texts contain key biomarkers about a patient's health. Evidence-based preventive medicine needs accurate semantic and sentiment analysis to extract and classify medical features as the input to appropriate machine learning classifiers. However, the traditional approach of using single classifiers is limited by the need for dimensionality reduction techniques, statistical feature correlation, a faster learning rate, and the lack of consideration of the semantic relations among features. Hence, extracting semantic and sentiment-based features from clinical text and combining multiple classifiers to create an ensemble intelligent system overcomes many limitations and provides a more robust prediction outcome. The selection of an appropriate approach and its interparameter dependency becomes key for the success of the ensemble method. This paper proposes a hybrid knowledge and ensemble learning framework for prediction of venous thromboembolism (VTE) diagnosis consisting of the following components: a VTE ontology, semantic extraction and sentiment assessment of risk factor framework, and an ensemble classifier. Therefore, a component-based analysis approach was adopted for evaluation using a data set of 250 clinical narratives where knowledge and ensemble achieved the following results with and without semantic extraction and sentiment assessment of risk factor, respectively: a precision of 81.8% and 62.9%, a recall of 81.8% and 57.6%, an F measure of 81.8% and 53.8%, and a receiving operating characteristic of 80.1% and 58.5% in identifying cases of VTE. 相似文献
68.
Wang Yi-Ting Shen Jie Li Zhi-Xu Yang Qiang Liu An Zhao Peng-Peng Xu Jia-Jie Zhao Lei Yang Xun-Jie 《计算机科学技术学报》2020,35(4):724-738
Journal of Computer Science and Technology - Entity linking (EL) is the task of determining the identity of textual entity mentions given a predefined knowledge base (KB). Plenty of existing... 相似文献
69.
Yong Xu Yun Li Songlin Li Francis Balestra Gerard Ghibaudo Wenwu Li Yen‐Fu Lin Huabin Sun Jing Wan Xinran Wang Yufeng Guo Yi Shi Yong‐Young Noh 《Advanced functional materials》2020,30(20)
Unreliable mobility values, and particularly greatly overestimated values and severely distorted temperature dependences, have recently hampered the development of the organic transistor field. Given that organic field‐effect transistors (OFETs) have been routinely used to evaluate mobility, precise parameter extraction using the electrical properties of OFETs is thus of primary importance. This review examines the origins of the various mobilities that must be determined for OFET applications, the relevant extraction methods, and the data selection limitations, which help in avoiding conceptual errors during mobility extraction. For increased precision, the review also discusses device fabrication considerations, calibration of both the specific gate‐dielectric capacitance and the threshold voltage, the contact effects, and the bias and temperature dependences, which must actually be handled with great care but have mostly been overlooked to date. This review serves as a systematic overview of the OFET mobility extraction process to ensure high precision and will also aid in improving future research. 相似文献
70.