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51.
Zhanbin Wang Jiahao Liu Houchao Shan Guozhen Li Ze Wang Zhihao Si Di Cai Peiyong Qin 《应用聚合物科学杂志》2020,137(42):49308
In this study, Schiff base network (SNW)-1 nanoparticles with high hydrophilicity and large specific surface area were used to prepare polyvinyl alcohol (PVA)-based mixed matrix membranes (MMMs), which were evaluated for ethanol dehydration. Because of the low difference of density between SNW-1 and PVA, the as-prepared nanoparticles can be uniformly distributed into the PVA active layer. The effects of SNW-1 loading, feed temperature, and water concentration on pervaporation (PV) performance were further studied. The results showed the MMM with 10 wt% of SNW-1 loading exhibited a separation factor of 1,501 and a permeation flux of 187 g m−2 h−1 for feeding 95 wt% ethanol/water binary solution at 75°C. Overall, the SNW-1/PVA MMMs showed great prospect in ethanol dehydration via PV. 相似文献
52.
Di Pu Ya-chun Xiong Ru-sen Feng Yong-jun Guo Ling Lin Cheng-jun Xu Wen-ke Yu 《Journal of surfactants and detergents》2020,23(6):1145-1157
In order to investigate the high interfacial activity and fair oil phase adaptability of alkanolamide, “1:1” type lauric acid diethanolamide impurities (LDEA) were synthesized and purified by the column chromatography method to obtain dodecanoic acid diethanolamide (C12DEA), ester mixture, etc. The exact structures of these compounds were further confirmed by IR, gas chromatogrph with mass spectroscopy (GC–MS), and NMR. The influence of each component on the interfacial tension of oil/water (IFT) was studied by systematic quantitative analysis. The results showed that (i) the strength of each system to reduce oil/water IFT is C12DEA /DEA ≈ LDEA > C12DEA/DEA/ESTER > C12DEA/NaOH > C12DEA > C12DEA/ESTER > DEA. This indicates that LDEA contributes to the reduction of the oil/water IFT and the enhanced adaptability of crude oil in this order: DEA > > ESTER; (ii) when the IFT of the LDEA/DEA system reached an ultralow value, the minimum content of DEA in the system was 1%, and the maximum ester content was less than 5% when the LDEA/DEA/ESTER system reached the ultralow IFT; (iii) the possible mechanism of effect of LDEA components on the IFT and oil phase adaptability was proposed as the synergistic process among the hydrogen bonding, alkali effect, and interface self-assembly of molecules in the interfacial layer. The contribution of these three factors were hydrogen bonding > alkali effect > interface self-assembly. 相似文献
53.
Maral Mahdad Chiara Eleonora De Marco Andrea Piccaluga Alberto Di Minin 《Industry and innovation》2020,27(3):264-284
ABSTRACTThis paper focuses on how companies deploy structural properties of adaptive capacity (multiplexity, redundancy and loose coupling) to cope with the phenomenon of internal challenges of Open Innovation (OI) implementation, i.e. organisational and cultural changes. We developed a single case study, which offered significant findings. First, the multiplexity of relationships in OI settings helps to face the challenges of organisational and cultural changes by triggering trust formation and interaction. Second, redundancy has twofold elements: institutional logics redundancy triggers cultural change challenges which can be overcome through management practices and communications; task redundancy facilitates knowledge sharing and collaboration, thus helping to deal with organisational change challenges. Finally, loose coupling in OI settings facilitates social interconnectedness among members through management practices, helping to face organisational and cultural change challenges. We provide managerial and theoretical implication to deal with the challenges of OI in relation to both organisational and cultural changes. 相似文献
54.
Marco Gobbetti Maria De Angelis Raffaella Di Cagno Andrea Polo 《Critical reviews in food science and nutrition》2020,60(13):2158-2173
AbstractIn the era of fighting wastes and paying close attention to sustainability and new protein sources, legumes, pseudo-cereals and milling by-products deserve all the efforts for increasing their consumption. Even with obvious peculiarities, a common trait characterizes these heterogeneous matrixes: unquestionable nutritional and functional value combined with some technological, sensory and/or anti-nutritional weaknesses, which unfortunately limit the exploitation and consumption. With the perspective of their use to fortify staple baked goods, we reviewed the main technological, nutritional and functional features of various legumes and pseudo-cereals, and milling by-products. Notwithstanding the potential of other technological solutions, we reported numerous evidences that qualified the sourdough fermentation as the most sustainable and powerful process to exploit the technological, nutritional and functional features of these matrixes and to limit or eliminate weak attributes. Sourdough fermentations tailored for specific matrixes allowed the fortification of staple baked goods with abundant levels of legumes, pseudo-cereals or milling by-products while keeping high consumer acceptance. 相似文献
55.
Samia Tássia Andrade Maciel Alexander Andrey Lopes da Silva Yasmin Guimarães Pedro Cristiano Nunes da Silva Leôncio Diógenes Tavares Câmara João Monnerat Araújo Ribeiro de Almeida Emerson Schwingel Ribeiro Gabriel Francisco da Silva Lisiane Santos Freitas Donato Alexandre Gomes Aranda 《化学工程与技术》2020,43(11):2149-2159
The catalytic hydrolysis of soybean oil was used as an alternative for the production of monoglycerides (MG) and diglycerides (DG). The reactions were conducted in a stainless-steel tubular reactor in the temperature range of 240–290 °C, on niobium phosphate (NBP) and niobium oxide (NBO) as catalysts. In the hydrolysis reactions at 270 °C, the maximum selectivities of the products of interest were obtained at 22 % MG and 48 % DG for the reaction with NBP, and 7 % MG and 33 % DG with NBO, for 59 % and 36 % of triglyceride conversion in 10 min, respectively. The proposed kinetic model presented a good fit of the theoretical model with the experimental data, showing that the previous hypotheses considered for the mechanism development are suitable for describing the kinetics of soybean oil hydrolysis. 相似文献
56.
面向踝部康复的广义球面并联机构型综合 总被引:3,自引:3,他引:0
针对现有踝关节康复机器人难以充分拟合踝关节复杂运动,人机相容性较差的问题,提出一系列与踝关节实际骨结构匹配程度更高的串联等效拟合模型。为满足踝关节串联等效拟合模型对康复机器人机构本体的功能需求,给出一种具有串联等效拟合模型的广义球面并联机构型综合方法。首先枚举出广义球面机构的基本构件及运动副,并依此构造出广义球面支链。继而基于螺旋理论分析单支链以及多支链组合对动平台的约束性能,给出支链的组合条件与原则,阐明不同支链在机构中作用的异同,并依此归纳出位置支链和姿态支链两类广义球面基本支链。最后基于基本支链的约束特性,根据支链组合条件,综合出一系列适用于踝关节康复机器人本体研究的广义球面并联机构,并通过螺旋理论证明其与踝关节串联等效拟合模型的自由度数及性质具有一致性,为此类康复机器人本体设计提供理论依据。 相似文献
57.
Francesco Di Girolamo Andrea Masotti Isabella Lante Margherita Scapaticci Cosima Damiana Calvano Carlo Zambonin Maurizio Muraca Lorenza Putignani 《International journal of molecular sciences》2015,16(9):20896-20912
Extra virgin olive oil (EVOO) with its nutraceutical characteristics substantially contributes as a major nutrient to the health benefit of the Mediterranean diet. Unfortunately, the adulteration of EVOO with less expensive oils (e.g., peanut and corn oils), has become one of the biggest source of agricultural fraud in the European Union, with important health implications for consumers, mainly due to the introduction of seed oil-derived allergens causing, especially in children, severe food allergy phenomena. In this regard, revealing adulterations of EVOO is of fundamental importance for health care and prevention reasons, especially in children. To this aim, effective analytical methods to assess EVOO purity are necessary. Here, we propose a simple, rapid, robust and very sensitive method for non-specialized mass spectrometric laboratory, based on the matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) coupled to unsupervised hierarchical clustering (UHC), principal component (PCA) and Pearson’s correlation analyses, to reveal corn oil (CO) adulterations in EVOO at very low levels (down to 0.5%). 相似文献
58.
59.
通过对粉煤灰砖抗折强度测量结果不确定度的评定,分析出影响试验结果的各种因素,为提高检测水平和精确度提供指导。 相似文献
60.