Ionic liquids (ILs) and deep eutectic solvents (DESs) have been suggested as eco-friendly alternatives to organic solvents. A trace amount of water is often unavoidable as impurity, and water is also ...added on purpose to reduce their problematically high viscosity and lower their high price. Understanding the distinct effects of water on the properties of ILs/DESs is highly important. In this review, we collect published experimental and theoretical results for IL/DES-H
2
O systems at varied water concentrations and analyze them. Results from mechanistic studies, thermodynamic modelling and advanced experiments are collected and critically discussed. Six commonly studied IL/DES-H
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O systems were selected to map experimental observations onto microscopic results obtained in mechanistic studies. A great variety of distinct contours of the excess properties can be observed over the entire compositional range, indicating that the properties of IL/DES-H
2
O systems are highly unpredictable. Mechanistic studies clearly demonstrate that the added H
2
O rapidly changes the heterogeneous 3D structures of pure ILs/DESs, leading to very different properties and behaviour. There are similarities between aqueous electrolytes and IL/DES solutions but the bulky and asymmetric organic cations in ILs/DESs do not conform to the standard salt dissolution and hydration concepts. Thermodynamic modelling previously assumes ILs/DESs to be either a neutral ion-pair or completely dissociated ions, neglecting specific ion hydration effects. A new conceptual framework is suggested for thermodynamic modelling of IL/DES-H
2
O binary systems to enable new technologies for their practical applications.
Comprehensive review of unique effects of water on ionic liquids and deep eutectic solvents observed in experimental and theoretical studies.
Lignocellulosic biomass is a potential sustainable feedstock to replace fossil fuels. However, the complex structure of biomass makes it difficult to convert into high-value products. Utilization of ...lignocellulosic biomass in a green and effective way is of great significance for sustainable development. Based on the analysis of different options, we proposed that cascade utilization according to its composition, characteristics, and nature is the best way to utilize the lignocellulosic biomass. To promote the cascade utilization of lignocellulosic biomass, this article provides a review of the latest research results from the aspect of cascade utilization of lignocellulosic biomass covering the whole chain from pretreatment to high-value products, and the research on the non-conventional pretreatments including microwave irradiation, supercritical fluids, ultrasonic irradiation, electric field, hydrodynamic cavitation, and ionic liquids are presented in detail and evaluated by 4 proposed levels, and the newly developed high-value applications were further overviewed for lignin (carbon/graphene/carbon nano-tubes, dye dispersants, bioplastics, and aerogels), cellulose (cellulose-based ionic liquids, functional composites, adsorbent materials, carbon, and aerogels), and hemicellulose (films and pharmaceutical carriers), respectively. Finally, perspectives on the future research on the cascade utilization of lignocellulosic biomass are highlighted.
► Modeling IL densities and gas solubilities in imidazolium-based ILs with ePC-SAFT. ► Different modeling strategies for ILs were compared within PC-SAFT. ► Pure-IL densities could be predicted from ...283 to 473K and up to 3000bar. ► The CO2 solubility in ILs could be predicted based on density-fitted parameters. ► The much lower solubility of CH4 compared to CO2 could be predicted.
ePC-SAFT was used to investigate the density and gas solubilities in imidazolium-based ionic liquids (ILs) applying different modeling strategies. The ion-based strategy including a Debye–Hückel Helmholtz-energy term to represent the ionic interactions describes the experimental data best. For this strategy, the IL was considered to be completely dissociated into a cation and an anion. Each ion was modeled as non-spherical species exerting repulsive, dispersive, and Coulomb forces. A set of ePC-SAFT parameters for seven ions was obtained by fitting to reliable density data of pure ILs up to 1000bar with a fitting error of 0.14% on average. The model can be used to quantitatively extrapolate the density of pure ILs at temperatures from 283 to 473K and pressures up to 3000bar. Moreover, this strategy allows predicting CO2 solubilities in ILs between 293 and 450K and up to 950bar. Applying the same set of IL parameters, the much lower solubility of CH4 compared to CO2 can also be predicted with ePC-SAFT.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The dynamics of bimolecular nucleophilic substitution (SN2) reactions in the gas phase are of great interest and several new mechanisms have been observed recently by theoretical studies. Here we ...investigate a recent-discovered SN2 reaction mechanism, called front-side complex (FSC) or halogen-bonded complex (XC) mechanism that couples the traditional front-side attack (FSA) and back-side attack (BSA) Walden-inversion mechanism. This XC-pathway begins with a front-side attack on the leaving group, then goes through a bending transition state (XTS) that is followed by Walden-inversion, and results in a configuration inverted product. We characterized the potential energy surface of the microsolvated Y−(H2O)n=0,1,2 + CH3I SN2 reaction using the B97-1/ECP/d method, where Y = HO, F, Cl, Br, and I, and n is the number of water molecules. It is found that the XCs have a deeper well depth than the back-side attack (BSA) pre-reaction complexes for HO−/F− nucleophiles, indicating that the system can easily become trapped in the halogen-bonded complex well. The barriers of both FSA- and BSA-paths increase with incremental solvation, whereas the change of XTS depends on the type of nucleophile. When Y = HO/F, the order of the barriers is BSA < XC < FSA for n = 0–2, and the order inverts to XC < BSA < FSA for n = 1 (Y = Br/I) and n = 2 (Y = Cl/Br/I), where the latter suggests an increasing participation of the halogen-bonded complex in the SN2 reactions. Comprehensive analyses on the structure, charge distribution, and energetics of XC and XTS are provided. This work indicates that the halogen-bonded complex mechanism may be common for alkyl iodides and the information on the potential energy surface is useful in understanding the dynamics behavior of the title and analogous reactions.
Research in the field of Chinese as a foreign language (CFL) education has been increasing in the past decades. However, the number of studies on CFL teacher identity is limited. To bridge the gap, ...this study employed a qualitative method to explore Chinese CFL teachers' identity formation and reformation in Australian contexts. A Chinese-Australian language program was studied to examine the challenges, struggles and developments of Chinese CFL teachers who came to Australia to pursue professional growth. Five Master's theses and three interview participants were included to paint a picture of how Chinese CFL teachers interact internally and externally with a new environment. Guided by Mead's theory of self and other, we found that Chinese CFL teachers' identity formation and reformation in Australian classrooms are deeply influenced by their self-identification and their integration with others in the community. Cultural connectedness is a key for organizational attitudes in the relationship of self and other. Chinese CFL teachers were found lacking the wholeness of self in Australian contexts, which led to obstacles in teacher identity construction. Insufficient communication between self and other resulted in their positioning crisis.
Introduction
This mixed-methods study investigates the impact of augmented reality (AR) on the development of intercultural competence and L2 (second language) learning motivation among Chinese ...English as a Foreign Language (EFL) learners. The research comprised forty-eight intermediate-level learners who were randomly assigned to either an experimental group, receiving AR-based language instruction, or a control group, receiving traditional instruction.
Methods
Both groups underwent pre- and post-tests to assess their intercultural competence and L2 learning motivation. The experimental group engaged with an AR application, which exposed learners to a variety of cultural scenarios, customs, and norms.
Results
The results indicate that the experimental group, exposed to AR-based instruction, demonstrated significantly higher levels of intercultural competence and L2 learning motivation in comparison to the control group.
Discussion
Qualitative data analysis further elucidated that AR-based instruction enhanced learners’ engagement, motivation, and deepened their cultural understanding. This study highlights the potential of augmented reality as a powerful tool for fostering the development of intercultural competence and L2 learning motivation within the EFL context, suggesting promising opportunities for innovative pedagogical approaches in language education.
Objective
This study aims to systematically review the application of artificial intelligence (AI) techniques in gastric cancer and to discuss the potential limitations and future directions of AI in ...gastric cancer.
Methods
A systematic review was performed that follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Pubmed, EMBASE, the Web of Science, and the Cochrane Library were used to search for gastric cancer publications with an emphasis on AI that were published up to June 2020. The terms “artificial intelligence” and “gastric cancer” were used to search for the publications.
Results
A total of 64 articles were included in this review. In gastric cancer, AI is mainly used for molecular bio-information analysis, endoscopic detection for Helicobacter pylori infection, chronic atrophic gastritis, early gastric cancer, invasion depth, and pathology recognition. AI may also be used to establish predictive models for evaluating lymph node metastasis, response to drug treatments, and prognosis. In addition, AI can be used for surgical training, skill assessment, and surgery guidance.
Conclusions
In the foreseeable future, AI applications can play an important role in gastric cancer management in the era of precision medicine.
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EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The CO2 solubilities (including CO2 Henry's constant) in physical- and chemical-based ILs/DESs and the COSMO-RS models describing these properties were comprehensively collected and summarized. The ...summarized results indicate that chemical-based ILs/DESs are superior to physical-based ILs/DESs for CO2 capture, especially those ILs have functionalized cation and anion, and superbase DESs; some of the superbase DESs have higher CO2 solubilities than those of ILs; the best physical- and chemical-based ILs, as well as physical- and chemical-based DESs are BMIMBF4 (4.20 mol kg−1), DETAHIm (11.91 mol kg−1), L-Arg-Gly 1:6 (4.92 mol kg−1) and TBD-EG 1:4 (12.90 mol kg−1), respectively. Besides the original COSMO-RS mainly providing qualitative predictions, six corrected COSMO-RS models have been proposed to improve the prediction performance based on the experimental data, but only one model is with universal parameters. The newly determined experimental results were further used to verify the perditions of original and corrected COSMO-RS models. The comparison indicates that the original COSMO-RS qualitatively predicts CO2 solubility for some but not all ILs/DESs, while the quantitative prediction is incapable at all. The original COSMO-RS is capable to predict CO2 Henry's constant qualitatively for both physical-based ILs and DESs, and quantitative prediction is only available for DESs. For the corrected COSMO-RS models, only the model with universal parameters provides quantitative predictions for CO2 solubility in physical-based DESs, while other corrected models always show large deviations (> 83%) compared with the experimental CO2 Henry's constants.
The CO2 solubility (including Henry's constant) in ILs/DESs and the COSMO-RS models describing these properties were collected, and compared with the original and corrected COSMO-RS prediction results. Then the best CO2 solubility and the performance of COSMO-RS models were achieved. Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•CO2 solubility in imidazolium-based ionic liquids was surveyed and evaluated.•CO2 absorption enthalpy was calculated based on thermodynamic model.•The effects of cation and anion on CO2 absorption ...enthalpy were discussed.•Energy consumption for a CO2 separation process was investigated.
CO2 solubility in ionic liquids has been measured extensively in order to develop ionic liquid-based technology for CO2 separation. However, the energy consumption analysis has not been investigated well for such technology. In order to carry out the energy consumption analysis for CO2 separation using ionic liquids based on available experimental data, in this work, the experimental data of the CO2 solubility in imidazolium-based ionic liquids at pressures below 10MPa was surveyed and evaluated by a semi-empirical thermodynamic model firstly. Based on the reliable experimental solubility data, the enthalpy of CO2 absorption was further calculated by the thermodynamic model. The results show that the CO2 absorption enthalpy in the studied ionic liquids is dominated by the enthalpy of CO2 dissolution and the contribution of excess enthalpy increases with increasing CO2 solubility in ionic liquids. The magnitude of the CO2 absorption enthalpy decreases with increasing chain length in cation and strongly depends on the anion of ionic liquids. Furthermore, the energy consumption for a CO2 separation process by pressure swing and/or temperature swing was investigated. For the pressure swing process, the Henry’s constant of CO2 in ionic liquids is an important factor for energy consumption analysis; If CO2 is absorbed at 298K and 1MPa and ionic liquid is regenerated by decreasing the pressure to 0.1MPa at the same temperature, among the studied ionic liquids, emimEtSO4 is the solvent with the lowest energy consumption of 9.840kJ/mol CO2. For the temperature swing process, the heat capacity of ionic liquids plays a more important role; If CO2 is absorbed at 298K and desorbed at 323K and 0.1MPa, emimPF6 is the solvent with the lowest energy demand of 888.9kJ/mol CO2. If the solvent is regenerated by releasing pressure and increasing temperature, both the Henry’s constant of CO2 in ionic liquids and the heat capacity of ionic liquids are important for analyzing the energy consumption; If CO2 is absorbed at 298K and 1MPa and ionic liquid is regenerated at 323K and 0.1MPa, bmimTf2N is the solvent with the lowest energy consumption of 57.71kJ/mol CO2.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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