Realizing improved strength–ductility synergy in eutectic alloys acting as in situ composite materials remains a challenge in conventional eutectic systems, which is why eutectic high-entropy alloys (EHEAs), a newly-emerging multi-principal-element eutectic category, may offer wider in situ composite possibilities. Here, we use an AlCoCrFeNi2.1 EHEA to engineer an ultrafine-grained duplex microstructure that deliberately inherits its composite lamellar nature by tailored thermo-mechanical processing to achieve property combinations which are not accessible to previously-reported reinforcement methodologies. The as-prepared samples exhibit hierarchically-structural heterogeneity due to phase decomposition, and the improved mechanical response during deformation is attributed to both a two-hierarchical constraint effect and a self-generated microcrack-arresting mechanism. This work provides a pathway for strengthening eutectic alloys and widens the design toolbox for high-performance materials based upon EHEAs.

The self-assembly of a zinc salt with the novel ligand 4,4',4″-[(1,3,5-triazine-2,4,6-triyl)tris(sulfanediyl)]tribenzoic acid generated 3D microporous metal-organic frameworks (MOFs), namely, {[Zn(L)(O)(HO)]·4EtOH} . The frameworks with multiple Lewis basic sites exhibit easily sensitized properties. After encapsulation of the Tb cation in this Zn-MOF, the as-obtained fluorescent-functionalized Tb@Zn-MOFs not only maintain distinguished chemical stabilities but also exhibit strong characteristic emissions of trivalent terbium ions. Interestingly, Tb@Zn-MOF has been chosen to be a potential highly selective and sensitive luminescent platform for the reversible detection of PO ions in aqueous and living cell buffer solutions with a fast response time of 10 s and a low detection limit (0.1 ppm). Strikingly, this work presents the first example of a fluorescent sensor that can quantitate PO in simulated biological fluids and monitor these ions in the water system in a wide range of concentrations from 10 to 10 M.

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Intangible cultural heritage (ICH) has recently become an important area of tourism development for many countries that are home to such cultural resources. Within this context, the value of an ICH site has often been used to guide tourism development and policy making. In addition, community residents’ attitude and perception of ICH contribute to tourism development. In this study, we used the traditional firing technology of Longquan celadon in Zhejiang Province, China, as a case study to understand the relationships between value recognition and attitude along with the intention to visit the heritage site. We surveyed 368 residents and conducted path analysis to test such relationships. Findings revealed significant positive correlations between residents’ cognition of ICH value, their attitudes and travel intentions. Among them, attitudes played a mediating role in the formation of value cognition to travel intention. These findings offer insights into ICH-related tourism development, particularly regarding tourism product design, marketing and post-development evaluation, as well as the conservation of ICH sites.

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Given the influence of the financial-economic crisis, hotel room demand in Hong Kong has experienced a significant drop since June 2019. Given that studies on the room rate aspect remains limited, this study considers the demand for hotel rooms from different categories and districts. This study makes forecast attempts for room rates from mid-October of 2019 to mid-June of 2020, which was a difficult period for Hong Kong owing to the onset of the social unrest and novel coronavirus outbreak. This study develops an approach to the short-term forecasting of hotel daily room rates on the basis of the Long Short-Term Memory (LSTM) model by leveraging the key properties of day-of-week to improve accuracy. This study collects a data set containing 235 hotels of the period from various online distribution channels and generates different time series data with the same day-of-week. This study verifies the proposed model through three baseline models, namely, autoregressive integrated moving average (ARIMA), support vector regression (SVR), and Naïve models. Findings shed light on how to lessen the impact of violent fluctuations by combining a rolling procedure with separate day-of-week time series for the hospitality industry. Hence, theoretical and managerial areas for hotel room demand forecasting are enriched on the basis of adjusting room pricing strategies for hoteliers in improving revenue management and making appropriate deals for customers in booking hotel rooms.

A luminescent terbium metal–organic framework [Tb(HPIA–)(PIA2–)(H2O)2] (Tb-MOF), synthesized by a lanthanide metal ion (Tb3+) and nitric heterocyclic carboxylic acid ligands H2PIA (H2PIA = 5-(1H-pyrazol-3-yl)isophthalic-acid), was structurally characterized as a three-dimensional skeleton structure in which layered coordination frameworks are connected by hydrogen bonds. Based on the antenna effect, Tb-MOF can emit bright green fluorescence under 254 nm excitation, and the fluorescence emission presents excellent durability in aqueous solutions among a wide pH range. Moreover, the structure of Tb-MOF also possesses outstanding thermal stabilities. In some ways, PO43– and its derivatives are thought to be a kind of pollutant ion causing series environmental and health problems. The as-synthesized Tb-MOF exhibits prominent selectivity and remarkable sensitivity for detecting PO43– as an easy-to-use fluorescent probe with low detection limit, fast response, and wide detection range. Therefore, Tb-MOF has significant applications in the fields of human health and environmental monitoring.

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