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Due to the impact of the COVID-19 pandemic, new attraction ways are tended to be adapted by compelling sites to provide tours product and services, such as virtual reality (VR) to visitors. Based on human-computer interaction (HCI) user engagement and domain segmentation innovativeness theory, we develop and test a theoretical framework using a hybrid partial least squares structural equation model (PLSSEM) with Importance Performance Matrix (IMP) and neural network machine learning approach (PLSSEM-IMP-NN) that examines key user engagement drivers of visitors’ attitude toward VR (ATT) and in-person tour intentions (ITI) during COVID-19. According to a sample of visitors' response, the results demonstrate that a) user engagement including aesthetic appeal, focused attention, perceived usability, and reward experience, raise attitude toward VR; b) product-possessing innovativeness positively moderates the relationships between ATT and ITI; c) information-possessing innovativeness negatively moderates the relationships between ATT and ITI; d) ATT exert the mediating effect between user engagement and ITI. The proposed new PLSSEM-IMP-NN approach has been examined and denotes its efficient and effective in HCI and behavioral response assessment. Other contributions to theories and practical implications are discussed accordingly.

Pressure swing adsorption (PSA) is an attractive technology for low-concentration CO2 removal from confined spaces. In this study, the dynamic process simulation of PSA with four adsorbents (e.g., ...

Sludge-based activated carbon with doped Phragmites australis was prepared using an environment-friendly method to treat waterworks sludge (WS) and obtain an economical adsorbing material for tetracycline (TC) elimination. For the WS, P. australis was used as an additive to optimize the preparation of activated carbon. Optimum preparation conditions were as follows: activation temperature, 600 °C; ZnCl2 concentration, 3 mol/L; activation time, 50 min; impregnation ratio (weight of mix sample: weight of ZnCl2) of 1:2.5; and the mixed ratio of P. australis with WS, 40%. The obtained activated carbon owned well-developed Brunauer–Emmett–Teller surface area (949.90 m2/g). The acidic and basic functional groups were improved to 0.762 and 0.016 mmol/g, respectively. The pseudo-second-order kinetic and Freundlich isotherm equations were more suitable models to simulate adsorption with the maximum adsorption capacity of 153.4 mg/g. According to the thermodynamic parameters, the adsorption process was spontaneous and endothermic. Electrostatic interaction, hydrogen bonding formation, and ion complexation adsorption mechanisms were the mechanisms underlying the adsorption of TC.

Absorption and adsorption technology as widely used methods have been reported for carbon dioxide (CO2) separation. In order to combine the advantages of absorption and adsorption methods, ionic liquids (ILs) as absorption function and zeolitic imidazolate framework-8 (ZIF-8) as adsorption function were integrated into a slurry to efficiently capture CO2 by the absorption-adsorption method. In this study, two pyridinium-based ILs, [C4Py][NTf2] and [C4Py][N(CN)2] were synthesized, and mixed with different concentration of ZIF-8 to form hybrid slurries. CO2 solubility in the different hybrid slurries at temperatures from 303.15 to 333.15 K was measured. The results indicated that CO2 solubility increases significantly with increasing pressure and decreases with increasing temperature. Moreover, CO2 solubility increases with the increase of ZIF-8 content, indicating that the addition of ZIF-8 into ILs can obviously enhance CO2 solubility. CO2 solubility in the ZIF-8/[C4Py][NTf2] slurry increases by 24% compared with the corresponding pure IL at 303.15 K and 1.80 MPa. The absorption-adsorption mechanism was studied using FT-IR and NMR spectroscopy. It was demonstrated that CO2 absorption and adsorption in the ZIF-8/ILs hybrid slurries is a physical process. Furthermore, the ZIF-8/[C4Py][NTf2] slurry can also keep the stable absorption performance after five consecutive absorption and desorption cycles. Considering the excellent capacity, thermal stability and recyclability, the porous materials/ILs slurry will provide new insight to CO2 capture compared with the conventional absorbents.

A large number of NH3 emissions from industries, such as ammonia plant purge gas, tail gases of urea plants and ammonium molybdate plants, inevitably cause serious air pollution problems, such as fog and haze, which has raised extensive attentions worldwide. However, the commercial methods, like water scrubbing and acid scrubbing, substantially transfer the NH3 pollute from gas phase to liquid or solid phase, which does not mean total elimination. How to realize efficiently separate and recover NH3 form NH3-containing gas mixtures is still a great challenge. In order to develop efficient absorbents for NH3 removal, a series of metal (copper (Cu), stannum (Sn), nickel (Ni), manganese (Mn), cadmium (Cd), zinc (Zn), ferrum (Fe)) ionic liquids (MILs) were synthesized, and their physicochemical properties and NH3 absorption performance were systematically investigated. The results implied that the incorporation of metal center into ILs has a great effect on NH3 absorption. Among the investigated MILs, bis(1-butyl-3-methyl imidazolium) copper tetrachloride salt ([Bmim]2[CuCl4]) and bis(1-butyl-3-methyl imidazolium) stannum tetrachloride salt ([Bmim]2[SnCl4]) show excellent NH3 absorption capacities up to 0.172 gNH3·gIL−1 and 0.106 gNH3·gIL−1, respectively, which are far more than most of the conventional ILs. Moreover, the high selectivity for NH3/N2, NH3/CO2 and NH3/O2 of [Bmim]2[CuCl4] and [Bmim]2[SnCl4] indicated that these MILs can selectively separate NH3 from NH3-containing gases. The absorption mechanism was further studied using Fourier transform infrared (FT-IR) spectroscopy and quantitative chemical calculations. It was demonstrated that the chemical complexation between [Bmim]2[CuCl4] and NH3 plays a dominant role in NH3 absorption, but the stronger hydrogen bonding between [Bmim]2[SnCl4] and NH3 enhances the absorption performance. In addition, [Bmim]2[SnCl4] can keep good stability after five absorption and desorption cycles, implying this MIL shows great potentials as an efficient and reversible absorbent for NH3 capture applications.

Ubiquitous learning (u-learning) has been recognized as an exciting approach to knowledge acquisition and skill development. However, a few studies have examined the factors influencing employees' acceptance of u-learning in a ubiquitous computing environment, and the impact of interaction-oriented learning systems' design factors on usage intention (UI) is rare as well. This paper proposes an integrated model derived from the technology acceptance model (TAM) by focusing on users' perceptions of interactivity (INT), software, and hardware design factors. A questionnaire survey was used, and responses of 368 Chinese knowledge workers as learners in Beijing were analyzed using the partial least square structural equation model. This paper successfully integrated three sub-dimensions-interaction, software, and hardware design-into a learning systems design model from a user perspective. The results reveal that perceived INT, perceived content, and perceived infrastructure significantly influence how employees adopt u-learning. This paper is among the first ones to explore INT as a critical factor influencing employee u-learning. Furthermore, it also explored two attitude dimensions toward “formal” and “informal” u-learning formats and found that these attitudes influence UI, and based on that the TAM is extended. This paper contributes to the literature by investigating the factors affecting employee acceptance of u-learning technology. This paper has several implications for both researchers and practitioners of u-learning and in the educational technology context.

The complex interaction between cations and anions as well as the molecular structure makes the ionic liquids (ILs) different from organic solutions. Thus, the conventional hydrodynamic models, which are suitable for water and organic solutions, are not able to predict bubble behaviors in ILs accurately. In this work, a new FCCS (Fragment Contribution Corresponding State)-CFD(CFD) coupled method is proposed, so that the influence of molecular structure of ILs can be revealed. A source term which represents the electrostatic interaction between cations and anions of ILs is introduced into the momentum equation, which makes the model reflect strictly the inner feature of ionic liquids. The simulation results show that the relative error of aspect ratio is only 0.06%, much lower than 3.73% which is calculated by the conventional method, indicating the new method is more accurate. Furthermore, the bubble behaviors, i.e. the bubble shape and velocity, in 30 ILs are simulated. As a result, the relationship between molecular structures of ILs and bubble behaviors, as well as the bubble flow regime is obtained.

In this work, pyridinium-based ionic liquids (ILs) were prepared and showed excellent performance in selective separation of H2S owing to existing active proton in H2S molecule. A series of pyridin...

Ammonia (NH3) emissions have caused a wide range of environmental problems and serious harm to human health. However, efficiently separating NH3 and simultaneously recovering high purity NH3 easily remains a great challenge. A new strategy to design transition metal ionic liquids (MILs) by combining specific metal centers and ligands with ILs was proposed for efficient and reversible absorption of NH3. Not only exceptional NH3 absorption capacity and high NH3/CO2 selectivity, but also excellent recyclability were achieved by cobalt ILs [Cnmim]2[Co(NCS)4]. The maximal capacity of NH3 is up to 6.09 mol NH3 mol IL−1 at 30 °C and 0.10 MPa, which is much higher than all reported ILs to date, and is over 30 times higher than the conventional ILs [Cnmim][SCN]. The superior NH3 capacity and desorption performance originate from the moderate Lewis acid–base and cooperative hydrogen bond interactions between the metal center-ligands and NH3.

BACKGROUND Ionic liquids have become potential absorbents to treat exhausted gases containing NH3, which threatens the living environment of human beings. RESULTS In this study, 10 kinds of protic and conventional ILs were synthesized and characterized and their densities, viscosities and thermal decomposition temperatures were measured. The NH3 solubility in ILs from the VLE experiments revealed that the chain length of cations had little influence on the NH3 solubility of the protic ILs because of the high NH3 capacities in protic ILs resulting from protic hydrogen atom compared to the conventional ILs. Besides, the 2-H atom on the cation influenced the NH3 solubility in both protic and conventional ILs with different trends as the pressure increased. Considering the effect of anions with the same cation [Bim]+, the order of NH3 solubility in protic ILs was [Bim][NTf2] > [Bim][SCN] > [Bim][NO3]. Dynamic absorption of NH3 in [Eim][NTf2] preliminarily revealed that the absorption was fast under ambient pressure and through 5 cycles of absorption and desorption, the NH3 absorption ability kept stable. CONCLUSIONS The relationship between the NH3 solubility and the structures of both protic and conventional ILs were revealed, indicating the protic ILs as an alternative material for the treatment of NH3 - containing exhausted gases.

CO 2 capture with ionic liquids (ILs) has attracted many attentions, and most works focused on absorption ability at ambient temperatures, while seldom research was concerned at elevated temperatures. This not only limits the CO 2 absorption application at elevated temperature, but also the determination of the operation condition of the CO 2 desorption generally occurring at higher temperature. This work mainly reported CO 2 solubilities in ILs at elevated temperatures and related properties were also provided. 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C n MIm][Tf 2 N]) ILs were selected as physical absorbents for CO 2 capture in this work due to their relative higher CO 2 absorption capacities and good thermal stabilities. The long-term stability tests showed that [C n MIm][Tf 2 N] is thermally stable at 393.15 K for long time. CO 2 solubilities in [C n MIm][Tf 2 N] were systematically determined at temperatures from 353.15 K to 393.15 K. It demonstrated that CO 2 solubility obviously increases with the increase of pressure while slightly decreases with increase of temperature. As the length of alkyl chain on the cation increases, CO 2 solubility in ILs increases. Additionally, the thermodynamic properties including the Gibbs free energy, enthalpy, and entropy of CO 2 were also calculated.

Ionic liquids (ILs) are recognized as novel solvents for both acid and base gases separations in industrial processes to solve the possible problems caused by the traditional organic solvent methods, such as high energy consumption and second pollutions. In this paper, the absorption performance and absorption mechanism of several typical gases, including CO2, SO2, H2S and NH3, in conventional and functionalized ILs are briefly summarized and discussed. Besides, the method of screening ILs with COSMOS-RS, and the process simulation, assessment and design for new IL-based gas separation processes are also reviewed.

Polycyclic aromatic hydrocarbons (PAHs) pose adverse risks to ecosystems and public health because of their carcinogenicity and mutagenicity. As such, the extensive occurrence of PAHs represents a worldwide concern that requires urgent solutions. Wastewater treatment plants are not, however, designed for PAH removal and often become sources of the PAHs entering surface waters. Among the technologies applied in PAH remediation, constructed wetlands (CWs) exhibit several cost-effective and eco-friendly advantages, yet a systematic examination of the application and success of CWs for PAH remediation is missing. This review discusses PAH occurrence, distribution, and seasonal patterns in surface waters during the last decade to provide baseline information for risk control and further treatment. Furthermore, based on the application of CWs in PAH remediation, progress in understanding and optimising PAH-removal mechanisms is discussed focussing on sediments, plants, and microorganisms. Wetland plant traits are key factors affecting the mechanisms of PAH removal in CWs, including adsorption, uptake, phytovolatilization, and biodegradation. The physico-chemical characteristics of PAHs, environmental conditions, wetland configuration, and operation parameters are also reviewed as important factors affecting PAH removal efficiency. Whilst significant progress has been made, several key problems need to be addressed to ensure the success of large-scale CW projects. These include improving performance in cold climates and addressing the toxic threshold effects of PAHs on wetland plants. Overall, this review provides future direction for research on PAH removal using CWs and their large-scale operation for the treatment of PAH-contaminated surface waters.

Pressure and Temperature Swing Adsorption (PTSA) is an appealing purification technology for removing low CO2 concentration from confined space potentially. In this work, a systematic method integrating dynamic process simulation, sensitivity analysis, process optimization, and energy consumption assessment was established to investigate a PTSA process of low CO2 concentration separation in the confined space using two adsorbents (Zeolite 13X and NaUSY). The dual site Langmuir adsorption isothermal models of N2 and CO2 were established, and calculated results showed good agreement with the experimental data. After parametric sensitivity analysis, key operational parameters (i.e. adsorption pressure, desorption pressure, regeneration temperature and P/F ratio) were optimized to achieve minimum process energy consumption. Those results indicated that Zeolite 13X was a good candidate for separating low concentration CO2 from confined space with lower energy consumption (55.03 kJ·Nm−3 N2). The simulation result can provide a novel strategy for removing low CO2 concentration from confined space.

Purpose The purpose of this paper is to investigate and examine the factors contributing to consumers’ mobile shopping continuance intention (CI) of food and non-food items via smartphones and other mobile terminals. Design/methodology/approach An integrated model was proposed on the basis of the technology acceptance model (TAM) and expectation confirmation model (ECM), focussing on perceived value (PV). The survey responses of 203 Chinese mobile shoppers (m-shoppers) were analysed using structural equation modelling with the partial least squares approach. Findings The results indicated that perceived usefulness does not motivate all user groups. Furthermore, satisfaction and perceived ease of use significantly impacted different user groups. For online food m-shoppers, value for money (VM) was the most important factor influencing satisfaction and CI. However, perceived usefulness only affected CI for non-food m-shoppers. Practical implications Marketers can improve users’ CI by enhancing VM and maximising effectiveness and enjoyment while minimising prices. Moreover, in determining strategies for different users, marketers should identify the behavioural differences among all groups and those between the two classified groups. Originality/value This is one of the studies attempting to explain Chinese mobile shopping consumers’ CI, but especially through an integrated model based on TAM and ECM with PV on food and non-food m-commerce perspective. It offers several implications for researchers and practitioners and contributes to the literature of technology acceptance and post-adoption behaviour in m-commerce.

Cost-efficient and environmentally benign treatment of NH3-containing exhaust gas has been a challenge. Ionic liquids (ILs) due to their unique structures and properties are recognized as potential solvents to absorb NH3. In this study, three types of ILs, including [Bmim][NTf2], [Bim][NTf2], [HOOC(CH2)3mim][NTf2], were designed and synthesized with various hydrogen bond donating abilities and characterized based on their thermodynamic dissociation constants (pKa). The results showed that protic ionic liquid (PIL) [Bim][NTf2] with a moderate pKa value had the highest NH3 absorption capacity (up to 2.69 mol NH3 per mol IL, 313 K, 100 kPa). Experimental characterization and theoretical calculations verified that such extremely high NH3 absorption capacity for [Bim][NTf2] resulted from the interactions between H-3 on the imidazole ring and the NH3 molecule and NH3 molecules sintering themselves. Furthermore, stable absorption performance was recorded for [Bim][NTf2] over four cycles, implying potential applications in the industry for NH3 recycling.

A typical biogas system with three utilization pathways, i. e., biogas upgrading, biogas combined heat and power (CHP), biogas solid oxide fuel cells (SOFCs) were designed. It was assessed from the viewpoint of energy, environment and economy by using energy efficiency, green degree and net present value index respectively. The assessment considered the trade-off relationships among these indexes, which is more comprehensive than previous systematic evaluation work only included single or two of the pathway(s) by using one or two of the index(es). Assessment results indicated that biogas upgrading pathway has the highest systematic energy efficiency (46.5%) and shortest payback period (8.9 year) with the green degree production is the lowest (9.29 gd/day). While for biogas SOFC pathway, although the green degree production is the highest (21.77 gd/day), the payback period is longer (14.5 year) and the energy efficiency is 13.6% lower than the biogas upgrading pathway. (C) 2016 Elsevier Ltd. All rights reserved.

Ammonia (NH3) is one of the main reasons for the formation of aerosols. NH3 pollution mainly comes from a large amount of emissions in industrial production. Ionic liquids (ILs), as a green solvent, can efficiently separate and recover NH3 from industrial NH3-containing tail gas. In this work, novel protic ionic liquids (PILs) with hydrogen bond donating ability were designed and synthesized by incorporating six-membered N-heterocyclic compounds including pyridinium and piperidinium as cations. Three pyridinium-based PILs with single protic H showed higher NH3 capacity with the maximum of 3.078 mol NH3/mol IL at 313.1 K and 0.10 MPa than the piperidinium-based PILs with double interaction sites. However, there was obvious reduction in NH3 capacity for pyridinium-based PILs during absorption and absorption-desorption cycles. The reason is that the acidic protic H of cations of pyridinium-based PILs is easily stripped in supersaturated alkaline environment due to the smaller pKa of pyridine derivatives than that of NH3, forming the NH4+ and volatile neutral pyridine derivatives. This work will provide useful guidance to the design of novel ILs used for efficient and reversible absorption of NH3.

Ammonia (NH3) pollution poses a serious environmental threat. Ionic liquids (ILs) are regarded as potential solvents to treat NH3-containing gases because of their unique properties, including tunable structures and high affinity for NH3 molecules. In order to achieve an efficient and reversible absorption of NH3, a series of protic ionic liquids (PILs) with multiple active sites were designed by introducing acidic protons, as well as the Li+ ion into ILs, resulting in PILs with two acidic protons on cations ([2-Mim][NTf2] and [Im][NTf2]), as well as dual functionalised PILs with a Lewis acidic Li+-based anion and acidic protons on cations, namely, [2-Mim][Li(NTf2)2] and [Eim][Li(NTf2)2]. The NH3 absorption capacity of [Im][NTf2] was found to be 3.46 mol NH3/mol IL, which is the highest among the NH3 absorption capacities of all known nonmetallic ILs, and is ascribed to the hydrogen bonding interactions between the NH3 and PIL molecules. Furthermore, [2-Mim][Li(NTf2)2] exhibited the highest NH3 absorption capacity, with a value of 7.01 mol NH3/mol IL, which is about 30 times higher than that of conventional ILs. The superior NH3 absorption performance of the dual functionalised PILs is attributed to the combination of hydrogen bonding interactions between the protons and the NH3 molecules, and the formation of coordination complexes between the Li+-based anion and the NH3 molecules. Moreover, the ILs studied here exhibited excellent recyclability, indicating a great potential for their use in applications involving efficient and reversible NH3 absorption from NH3-containing industrial gases.

Two constructed wetland microbial fuel cell (CW-MFC) devices, experimental group (EG, with 5 mg/L Pb(II) addition) and control group (CG) were built to explore the changes in power generation, wastewater purification and microbial community structure under Pb(II) stress. The voltage of EG (343.16 ± 12.14 mV) was significantly higher (p0.01) than that of CG (295.49 ± 13.91 mV), and the highest power density of the EG and CG were 7.432 mW·m

In this work, three kinds of ether-functionalized pyridinium-based ILs [EnPy][NTf2] with low viscosity were designed and synthesized and used for highly selective separation of CO2 from CH4. It was found that the ether groups play an important role on physicochemical properties and CO2/CH4 selectivity in these three ILs. Compared with the nonfunctionalized analogues [CmPy][NTf2], the viscosities of [EnPy][NTf2] are lower and obviously decrease with the increasing number of ether oxygen atoms. The presence of ether groups on the cation has weak impacts on CO2 solubility of the ILs, but it contributes to a much lower CH4 solubility, which leads to the great increase of CO2/CH4 selectivity using [EnPy][NTf2]. Moreover, CO2/CH4 selectivity in all investigated ILs greatly decreases with the increasing temperature due to the weaker temperature dependence of CH4 solubility. In addition, the thermodynamic properties including the Gibbs free energy, enthalpy, and entropy of CO2 and CH4 in these ILs were also obtai...

Using protic ionic liquids (PILs) to treat ammonia (NH3)-containing exhausted gases is a potential method to mitigate the air pollution and realize the ammonia recovery in industries. In order to design a new process to absorb and recover NH3, the understanding of variations in physical properties of PILs during NH3 absorption is important for process design. In this work, the density and viscosity variations of PIL of 1-butylimidazolium bis(trifluoromethylsulfonyl)imide ([Bim][NTf2]) with different NH3 concentrations were measured. The results showed that the density of [Bim][NTf2]-NH3 system decreased linearly as NH3 concentrations increased, while the viscosity exhibited a turning trend, i.e., the viscosity first increased about 15% and then decreased sharply to a lower value. It is confirmed by the NMR spectra of d-[Bim][NTf2] (the proton was replaced with deuterium) that the hydrogen bond interaction exists in NH3 and the imidazole ring. Quantum chemistry calculations further indicated that properties variations of the PIL during NH3 absorption come from the changes of ionic interaction between the cation and anion and hydrogen bonding between PIL and NH3.

In order to study the architectural style of Mongolian lamaist temple combining the han and Tibetan styles, this paper analyzes three main halls of the temple built in different periods in the same village.Secondly, the process of deformation and combination of spatial prototype is decomposed through illustration. The following conclusions are drawn: 1. The temple architecture of lamaism in Inner Mongolia flexibly utilizes the architectural vocabulary of the two language families on the premise of satisfying the architectural function and accurately expressing the religious connotation; 2.2. The two architectural languages use different spatial dominant principles to express similar spatial connotations and reflect the basic cognition of buddhist cosmology;3. With the improvement of the craftsman’s ability to master the two languages, the ways of integration of the two languages are always changing, and the manifestations of the palace are diversified.