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Fiber-reinforced polymer matrix composites during engineering applications can be influenced by critical environmental conditions (e.g., water and temperature), probably causing a negative impact on the mechanical performance. In this work, the hygrothermal aging behavior and flexural property of carbon fiber (CF)-reinforced polyethylene terephthalate glycol (PETG) composites were investigated at different aging temperatures and days. The CF/PETG composites were fabricated using the hot-press molding method. The mathematical fitting model and finite element analysis method were employed to reveal the hygrothermal aging behavior and the moisture absorption evolution. After 90 days of aging, the water uptakes of the specimens at 25°C, 45°C, and 60°C are 0.55%, 0.62%, and 1.67% for PETG and 0.47%, 0.54%, and 1.52% for CF/PETG, respectively. The flexural strengths of the CF/PETG composites at 25°C, 45°C, and 60°C after 90 days of aging decrease by 28.6%, 30.2%, and 32.2% as compared with the non-aging composites, respectively. The water uptakes of the CF/PETG composites tend to increase with the increase in cyclic aging time interval. The flexural strengths of the composites with the cyclic aging intervals of 2, 5, 10, and 15 days first decrease and then increase slightly. The knowledge gained in this study will benefit future design optimization of the CF/PETG composite material and lay the foundation for its engineering application.

Purpose This study aims to explore how attribute performance and hosts’ service quality attributes affect room sales on peer-to-peer (P2P) platforms from the cue congruence perspective. Design/methodology/approach More than 9.53 million reviews concerning 258,473 listings located in 35 major cities worldwide were collected from Airbnb. Data was collected from December 2019 to December 2020 and was analysed using a generalised linear model. Findings Results show that when attribute performance and hosts’ service quality attributes give positive signals, Airbnb room sales are significantly higher than when the two kinds of cues give inconsistent or negative signals; when attribute performance gives positive signals and hosts’ service quality attributes give negative signals, room sales are higher than when the former gives negative signals and the latter give positive signals; surprisingly, when both kinds of cues give negative signals, room sales are higher than when attribute performance gives positive signals and hosts’ service quality attributes give negative signals. Research limitations/implications This paper adds useful insights on understanding of cue congruence (incongruence) effect on room sales of P2P accommodation platforms. This study has practical implications for hosts, online platform managers and guests regarding how to use online strategies and promotions on the Airbnb platform. Originality/value This study is an early attempt to explore how the combination of attribute performance and hosts’ service quality attributes affects Airbnb room sales under the conditions of consistency and inconsistency.

Simultaneous biodegradation of malodorous 1-propanethiol (PT) and dimethyl sulfide (DMS) inoculated with Pseudomonas putida S-1 and Alcaligenes sp. SY1 were investigated and interactions implicated were explored. Results showed that PT was completely degraded in 33 h, while a lag of 10 h was observed for DMS degradation alone, and the lag even extended to 81 h in the binary mixture. Mechanism analysis found that the lag was mainly attributed to the exposure of DMS degrader (Alcaligenes sp. SY1), rather than PT metabolites and PT degrader. The exposure time and PT concentration influenced the lag duration much. Citric acid could effectively reduce the lag. Pseudo first-order model was proved suitable for the description of PT degradation, revealing that PT degradation could be enhanced in presence of DMS regardless of its concentration. A modified Gompertz model, incorporated the lag phase, was developed for the description of DMS degradation in the mixture, revealing that DMS degradation depended on the initial PT concentration. When the lag was not considered, PT with low-concentration could promote DMS biodegradation, while a higher concentration (＞20 mg·L−1) cast negative effect.

The spatially isolated Ni2P and NiO dual-cocatalysts synergistically promoted CO2 photocatalytic conversion of CN, and the in situ formed Ni0 during photocatalytic reactions endowed the catalyst with sustainably efficient CO2 reduction activity.

Interfacial heating is the most obvious feature that distinguishes the novel solar driven interfacial heating from the traditional solar heating technology, and it is also a key factor in promoting solar energy utilization and vapor generation performance. However, the inherent trade-off between water supply and the interfacial heating performance of photothermal materials has rarely been investigated. Herein, an all-in-one designed bilayer evaporator consisting of a top solar absorber (Fe

Purpose This study aims to explore the dimensions and sub-factors of Airbnb hosts’ affinity-seeking strategies. It also aims to build a conceptual framework of hosts’ affinity-seeking strategies and their impact on Airbnb guests’ feelings of affection toward their host and/or the homestay and their behavioral intentions. Design/methodology/approach Based on 150,161 Inside Airbnb online reviews in three major US cities, this study uses semantic analysis to explore processes through which hosts’ affinity-seeking strategies are constructed. Findings A conceptual framework is proposed to identify two dimensions (warmth and competency) and their sub-factors (“presenting friendly attitudes,” “showing personality traits,” “providing service and help” and “promoting social interaction and sharing”) of Airbnb homestay hosts’ affinity-seeking strategies. The framework shows a positive relationship between these strategies and guests’ affection and behavior in response. Practical implications The research findings provide valuable insights to hosts for improving their affinity and strengthening their competitive advantages. They also offer guidance to destination management organizations on how to build a positive destination image. Originality/value To the best of the authors’ knowledge, this study is the first to conceptualize Airbnb homestay hosts’ affinity-seeking strategies. It contributes to the literature by incorporating social cognition theory and service theory in the analysis of these strategies.

Homestay hosts expend considerable social efforts to ensure that guests like their host and homestay. Despite the process of generating affinity for the hosts is central to social exchanges in homestays, there still lacks a valid scale to measure the affinity-seeking strategies of hosts. To address this gap, this study uses multi-step mixed methods to develop a measurement scale for the affinity-seeking strategies of homestay hosts. A formative hierarchical component model of the affinity-seeking strategies of hosts is proposed in this study. Four first-order formative indicators are validated, namely, presenting personal attractiveness, showing friendly attitudes, facilitating enjoyment and social contact, and providing service and help. Furthermore, the stimulus–organism–response (S–O–R) model is used to validate the second-order formative constructs. The results show that the affinity-seeking strategies of homestay hosts positively affect guests' emotional value and intention to cooperate with hosts. The findings contribute to a measurable definition of hosts’ affinity in the context of homestays.

Recently, water-borne fluorescent inks have attracted extensive attention in anti-counterfeiting applications due to their convenient implementation and eco-friendliness. However, due to poor service durability, the latent authorization information from the inks is easily damaged, and even disappears when encountering water. Moreover, most of the existing fluorescent inks are monochromic, toxic, and allergic to skin, thus are unsuitable for their sustainability during real-life applications. Herein, this work presents environment-friendly, durable, and multicolor fluorescent anti-counterfeiting silicon nanoparticles (SiNPs)/sodium alginate (SA) inks. The multicolor SiNPs are synthesized by a one-pot method with defined morphologies and optical properties. Subsequently, SA is employed as the binder to prepare the fluorescent inks with optimized rheological properties. Practicability results show that the SiNPs/SA inks not only exhibit excellent printability, but also impart authentic information with superior covert performance. More notably, spraying solution of calcium dichloride can further improve fluorescent fastnesses of the SiNPs/SA inks by ionic crosslinking.

Volatile organic compounds (VOCs) emitted from various industrial processes are extremely harmful pollutants. They are involved in the formation of ozone, photochemical smog, and fine particles (PM2.5) in the atmosphere, which pose considerable threat to human healthy and ecosystem safety. The hybrid plasma-catalytic technology that uses non-thermal plasma (NTP) and catalysts is an efficient method for VOC abatement. This review provides a comprehensive insight into the removal of VOCs with this technology. First, the synergistic effects and mechanisms of NTP and catalysts are discussed. Then, the properties of the catalysts, including types, positions, and other parameters, are explored. Specific examples of VOCs abated using the NTP-catalyst technology are reviewed, along with the main types and the causes of by-products. Several methods, such as the optimization of process parameters and the utilization of end control, are considered efficient for the regulation of product formations. Finally, future perspectives on the applications of this hybrid technology are briefly discussed.

Purpose This study aims to explore the impact of the belt and road initiative (BRI) on tourism development in China and to identify the factors contributing to the BRI’s effect on tourism development. Design/methodology/approach This study evaluates the impact of the BRI on tourism development using 2007–2017 panel data from 31 provinces and municipalities in China. The data are analyzed using the difference-in-differences method and the factors contributing to the BRI’s effect on tourism development are identified through an analysis of online reviews by users of a massive open online course offered on the FutureLearn platform. Findings The result suggests that the BRI has boosted total tourism revenue and total tourist arrivals in the BRI region comparing with other regions. Four factors contributing to the BRI’s impact on tourism development in China are identified: macro-environmental factors, transit factors, destination factors and tourism policy and promotional factors. Originality/value The BRI has had a significant impact on regional tourism development, yet very few empirical studies have systematically examined the impact of BRI on tourism development. Thus, this paper also addresses this research gap by evaluating the extent to which BRI impacts tourism development and contributes to the factors affecting tourism development.

Purpose This paper aims to answer the following four research questions: Where do tourists gaze at the destination? What do tourists gaze at the destination? How do tourists gaze differently? Why do tourists gaze differently referring to relevant theory? Design/methodology/approach With a computer vision approach, this study illustrated a series of maps that reflect where and what do tourists gaze at and compared the differences in the visual perceptions among Asian, European and North American tourists in Hong Kong. Findings The findings confirm that the “tourist gaze” is influenced by geographical and cultural conditions. The conclusions provided three types of implementations for destination management strategies and advocated a high engagement with computer vision technology. Originality/value In theory, this study proves that the “tourist gaze” is influenced by geographical and cultural conditions. The study’s methodological contribution lies in applying advanced technology of visual content analysis for big data relevant to the issue of the tourist gaze. Practically, the finding that has not been achieved via previous questionnaire surveys will serve as a reference for tourism recommendations and precision marketing. In addition, its practical contribution is that it offers a means by which to explore tourists’ perceptions of destinations and understand the attractiveness of destinations to tourists.

The treatment of waste-gas containing chlorinated volatile organic compounds (CVOCs) has become a difficult issue in current air pollution control. Biotrickling filters (BTFs) have been recognized to be applicable for the treatment of CVOCs, but research on the biodegradation of binary gaseous CVOCs is rare. Herein, a BTF inoculated with Methylobacterium (M.) rhodesianum H13, Starkeya sp. T-2 and activated sludge was established to investigate the biodegradation of the gaseous dichloromethane (DCM) and 1,2-dichloroethane (1,2-DCE) and their interactions implicated. The bioaugmented BTF showed a faster startup (13 days), better removal efficiencies of DCM (80%) and 1,2-DCE (72%), and superior mineralization (65.9%) than that inoculated with activated sludge alone. The ECs of DCM and 1,2-DCE were positively related with the inlet load when the total inlet load was50 g m

China has experienced severe air pollution in the past decade, especially PM

Volatile organic compounds (VOCs) are considered to be the main cause of air pollution and should be controlled strictly. Vacuum ultraviolet combined with cerium (Ce)-doped ZnO as the catalyst was investigated for the removal of para-xylene (p-xylene). Based on scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction analysis, the particle size decreased after cerium in the form of Ce3+ and Ce4+ was doped into the ZnO crystal structure. An improved photocatalytic activity (higher p-xylene removal efficiency) was obtained at 0.96% Ce doping, 351 °C calcination temperature, and 339 min calcination duration. Based on the investigation of process parameters, the removal efficiency of p-xylene reached 100% with an initial concentration of 150 mg m−3, a relative humidity of 50%, and a residence time of 60 s. The ozone utilization extent was 96%, suggesting that the remaining ozone after the photocatalysis of p-xylene could be well controlled. Four different kinetic rate equations were used, suggesting that p-xylene and water molecules competed for the same active site. Mechanism analysis suggested that four types of oxidation contributed jointly to the removal of p-xylene and they followed this order: oxidation by the reactive species (RS, mainly ˙OH, O3 and O(1D)) > oxidation by the synergistic interactions among photolysis, RS and h+ > transformation by direct photolysis > oxidation by h+.

This study explores the phenomenon of tourist arrivals to China from Mongolia and Russia before and after the “Belt and Road” (B&R) initiative. The objective of this work is to investigate the succ...

The construction of the Guangdong-Hong Kong-Macao Greater Bay Area (the Greater Bay Area) has injected new impetus into the development of the tourism economy and created new emerging tourism indus...

Dechlorination is the key step in biological degradation of dichloromethane (DCM), which is catalyzed by the enzyme DCM dehalogenase. In this study, the detailed structure and function of DCM dehalogenase in Methylobacterium rhodesianum H13 were investigated. Our results indicate that DCM dehalogenase (C1505H2255N403O430S7) is a stable hydrophilic protein localized in the cytoplasm, with an isoelectric point of 6.35. They also indicate that DCM dehalogenase is a frizzled protein with 52.43% of amino acid residues exposed on its surface, and that alpha-helices are a main structural component (53.47%). As one of the theta class glutathione S-transferases (GSTs), DCM dehalogenase presents as a dimeric structure and shows strong substrate selectivity. The catalytic tunnel radius and length of DCM dehalogenase are both 1.4 Å. Glu42 and Val43 are two of the essential amino acids in both the catalytic tunnel and catalytic pockets. The amino acid sequence of DCM dehalogenase was predicted to be homologous among various microorganisms, and its active site was conserved with eight potential sites. The recombinant DCM dehalogenase was expressed in E. coli BL21 strain. The optimum conditions for DCM dehalogenase are pH 8, temperature of 30 °C and presence of Mn2+. All the obtained information of DCM dehalogenase will lay the foundation for further study of its structural transformation and functional improvement.

Increasing carbon dioxide (CO2) concentrations threaten human production and life. Currently the equipment used for CO2 monitoring is heavy and expensive, without a portable CO2 detector that is inexpensive and resistant to interference. Here we designed a portable CO2 detector based on no-dispersive infrared sensors to measure CO2 concentration. The detector, which has a mass of 1 kg, is powered by a lithium battery with dimensions of 200 mm (length) × 150 mm (width) × 100 mm (height). Considering the fact that field observations are susceptible to humidity, a series of experiments were carried out to reduce the humidity interference on sensor responses at a laboratory. The values of humidity and CO2 variation were used in a regression model analysis to determine a quadratic function with an R2 above 0.94. The detector was compared with a reference analyzer in ambient CO2 measurement during a 7-day field campaign in Hangzhou, China. After humidity correction, the data show better correlation with the reference data, with the R2 0.62–0.97 increasing from 0.62–0.97 compared to before the correction and the value deviation decreasing to less than 3%. Cluster analysis of sensors revealed a reduction in average relative deviation of up to 1.4% as the number of sensors increased.

The rates of invariant natural killer T (iNKT) cells in vivo are very low, and the amounts of cells obtained directly from the body are hard enough to fulfill their potential in clinical application. To overcome this problem, we subcutaneously injected alpha-galactosylceramide (α-GalCer) into DBA/1 mice and thymic single cells were isolated and cultured in vitro. Fluorescence-activated cell sorting was used to detect the iNKT cells and their subsets in the thymus after the injection of α-GalCer by different methods. In addition, in vitro changes of single-cell suspensions and their cytokines in culture supernatants were assessed. Compared with the α-GalCer multiple subcutaneous injection group, the rates of iNKT cells in the α-GalCer single subcutaneous injection group were markedly higher at each time point, while the highest levels of iNKT1 and iNKT2 cells were observed on day 4 and 8, respectively. In α-GalCer single subcutaneous injection for 8 days and thymic mononuclear cell cultured for 14 days group, the expansion rate of iNKT cells was significantly faster than the other groups, while it reached a peak for iNKT1 cells. Interferon-gamma was consistent with the development of iNKT1 cells, however no difference was found between the cultured iNKT cells in vitro and the natural iNKT cells in vivo in terms of cytokine production. Herein, we introduced a method in which antigenic stimulation in vivo and directed induction in vitro yielded high levels of iNKT cells with specific functions.

A new strain, Pseudomonas sp. SJ-1, which was able to remove model odorous organics methanethiol (MT) has been isolated from the wastewater treatment plant and identified via 16S rRNA analysis. Initial MT concentration, temperature and pH played an important role in MT removal, and up to 100% of 260 mg L

A novel array double dielectric barrier discharge (ADDBD) combined with a TiO2/Al2O3-Co3O4/AC (Ti Co) catalyst was applied to remove toluene. The effects of catalyst setting distance, catalyst combination mode, and process factors (including specific input energy, initial toluene concentration, and relative humidity) were investigated in terms of the toluene degradation efficiency (ηtoluene) and the selectivity of CO2 (SCO2). When the specific input energy was 65 J·L−1, the initial toluene concentration was 100 mg·m−3, and the relative humidity was 30%, the highest ηtoluene of 72% and SCO2 of 44% could be achieved with TiO2/Al2O3 10 cm and Co3O4/AC 20 cm downstream of the ADDBD. Based on the determination of active substances (e.g., O3, OH) and the catalyst activation mode, a synergistic effect of active substances and photon between the ADDBD and the Ti Co catalyst was proposed for the removal of toluene. Finally, the biodegradability and toxicity of the outlet gas were evaluated, and the results showed that the outlet gas was more convenient for subsequent biopurification and less toxic to the surroundings after the treatment by the ADDBD combined with the Ti Co catalyst.

A biotrickling filter (BTF) inoculated with concentrated activated sludge possessing highly efficient degrading strains was investigated on a pilot-scale for the treatment of viscose fibre waste gas containing carbon disulfide (CS2) and hydrogen sulfide (H2S). The BTF had a quick start-up period, with 90.6% and 98.2% removal of CS2 and H2S, respectively, from the 18th day of acclimation. When the influent concentration was increased from 145 mg m−3 to 1912 mg m−3, steady removal efficiencies (REs) of above 70% for CS2 and 90% for H2S were achieved for the entire operation, with maximum elimination capacities (ECs) of 122.7 g m−3 h−1and 108.2 g m−3 h−1 for CS2 and H2S, respectively. The results showed that H2S was preferentially degraded by BTF, owing to hydrophilic H2S having a low Henry coefficient, which allowed it to adsorb on the biofilm surface more easily and made its biodegradation more favorable. The pH significantly affected the REs of CS2 and H2S, which decreased from 81% to 52% and from 95% to 73%, respectively, with a pH increase from 2 to 8, while sulfate accumulation did not significantly affect the pollutant REs. A tolerance experiment showed that BTF was resistant to large fluctuations in CS2 and H2S concentrations, with a RE of 80% recovered in only 2 days. Microbial diversity analysis showed that Acidithiobacillus, Acidiphilium, and Metallibacterium had higher relative abundances at the genus level, and remained persistent throughout the operation, implying that these strains played an important role in the simultaneous removal of CS2 and H2S from waste gas.