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With the exponential growth of online review platforms, understanding user preferences and interests in the tourism domain has become increasingly critical for businesses and service providers. However, extracting meaningful insights from the vast amount of available data poses a significant challenge. Traditional methods often struggle to capture the nuanced and hierarchical nature of user interests within the tourism domain. This paper pioneers the integration of domain information modeling technology into the realm of online review information mining, presenting a novel approach to constructing a user tourism interest model. Unlike existing methods, which primarily rely on flat or simplistic representations of user data, our approach leverages the hierarchical structure inherent in tourism domain information modeling. By harnessing big data within the tourism domain, we construct hierarchical tourism attributes and apply a conditional random field model along with an affective dictionary to facilitate the hierarchical mining of user travel interest information. This culminates in the establishment of a comprehensive user travel interest model using advanced information modeling techniques. Building upon this foundation, we further propose a dynamic user travel interest model, showcasing its adaptability and responsiveness to changing user preferences. Finally, we validate the accuracy and effectiveness of our model through simulation experiments within a user travel recommendation system, demonstrating significant improvements over traditional methods. [ABSTRACT FROM AUTHOR]

Pervaporation will have broad application prospects in the treatment of phenolic wastewater. Polyurethane (PU) membrane is promising but needs to be further modified. In this study, both β-CD and CNT were used to modify the PU membrane. The structure and property of these membranes were characterized by FTIR, DSC and TGA. The pervaporation performances were investigated, and the effects of β-CD and CNT on membrane separation were discussed. TGA shows that three kinds of modified membranes have enough thermal stability to afford pervaporation test and start weight loss at about 200 °C. In pervaporaiton, the total flux, separation factor and PSI value all increase with increased feed temperature. That is anti-trade-off phenomenon. Among these membranes, HTPB+β-CD-PU shows the best comprehensive performance at 80°C and has great potential for further application.

Abstract: The effect of thermal treatment on the formation and transformation of Al13 and Al30 species in highly concentrated hydrolytic polymeric Al solutions (HPA) (0.2–1.0molL−1) were studied quantitatively using high-field 27Al nuclear magnetic resonance (NMR) and time-developed Al-Ferron complex colorimetry. The results indicate that the metastable Al13 species in HPA tends to polymerize and transform into Al30 and other high polymers upon thermal treatment. The polymerization and transformation are speed up by heating at high temperature. Al13 content in HPA decreases upon thermal treatment, and Al30 content increases. Al13 does not convert to Al30 quantitatively due to its aggregation and acidic dissociation reactions. Al13 species is a dominant nanosized Al species in freshly prepared HPA solutions, and its content reaches above 80.0% in HPA with AlT =0.2molL−1 and optimal hydrolysis ratios (B) (ca. 2.3–2.4). But the content of Al30 becomes higher than that of Al13 when the HPA solution is heated at 95°C for more than 12h. Al30 becomes the dominant nanosized Al species in HPA, and its content reaches 76.8% in sample with AlT =0.2molL−1 and B =2.4. Although Al30 is more stable than Al13, it is also a metastable species during the process of Al hydrolysis, polymerization and precipitation. The decomposition and polymerization of Al30 are also speed up by increase the heating temperature. The optimal preparation temperature of Al30 is ca. 95°C. Al species in HPA solutions transform into more stable and inert species through inter-species polymerization and intra-species structure rearrangement upon thermal treatment. So Alb contents decrease, and Alc contents increase. Al30 cannot react with Ferron within 120min, and it is classified as Alc species in Al-Ferron analysis. The effect of thermal treatment on Al speciation in HPA solutions with different total Al concentration and B value were also investigated. [Copyright &y& Elsevier]

Abstract: Polyaluminum coagulant with a content of 76.8% of Al30 (PACAl30) was prepared. Its coagulation behaviors were compared with high Al13 content polyaluminum coagulant (PACAl13) and AlCl3. The species stability was studied using Al-Ferron method and 27Al NMR. The coagulation performances were investigated by studying the rate of flocs development, the turbidity removal efficiency and charge neutralization capacity under fixed pH conditions and uncontrolled pH conditions. The effect of pH on coagulation was also studied. The results show that PACAl30 are stable for using as coagulant. PACAl30 causes less pH depression than PACAl13. The charge neutralization capacity of PACAl30 is slightly lower than that of PACAl13 at pH⩾6.8 and higher at pH⩽6.5. PACAl30 achieves the most effective turbidity removal in these three coagulants. And it acts effectively within a much broader dosage range and a wider pH range when compared with PACAl13. PACAl30 achieves the highest turbidity removal due to its strong flocs formation capacity. The results verify that Al30 is another highly active coagulation/flocculation species for turbidity removal. [Copyright &y& Elsevier]