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Herein, wheat straw residue and pulping waste liquid were collected from pulping mill and mixed to prepare bio-based granular fuels by using compression molding technology, and to explore the comprehensive utilization of the industrial waste of pulping and papermaking. The effects of pulping waste liquid on granular fuel properties were analyzed systemically. Further study of the function of pulping waste liquid, cellulose and hemicellulose was used to replace wheat straw residue and avoid the interference factors. Therefore, the prediction models of granular fuels were established with influencing factors that included cellulose, hemicellulose and pulping waste liquid. The granular fuels had the best performance with 18.30% solid content of pulping waste liquid. The highest transverse compressive strength of granular fuel was 102.61 MPa, and the activation energy was 81.71 KJ·mol-1. A series of curve fitting prediction models were established to clarify the forming process of granular fuel, and it turned out that the pulping waste liquid could improve the adhesion between solid particles and increase their compression resistance.
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Cave Automatic Virtual Environment (CAVE) is a virtual reality (VR) environment that has not been fully studied due to its high cost and complexity in system integration. Previous CAVE-related studies mainly focused on comparing its effectiveness with other learning media, such as textbooks, desktop VR, or head-mounted display (HMD) VR. In this study, through the utilization of CAVE in a meteorology class, we concentrated on CAVE itself, measured how CAVE impacted learners' learning outcomes before and after using CAVE in an actual ongoing undergraduate-level class, and investigated how learners perceived their learning experiences. Quantitative data were collected to examine the students' knowledge acquisition and learning experience. We also triangulated the quantitative results with qualitative data from the interviews regarding learners' perceptions of the CAVE-enabled class and their knowledge mastery. The results indicated that their learning outcomes increased through learning with CAVE and that their perceptions of immersion, presence, and engagement significantly correlated with each other. The interview results showed a great fondness of and satisfaction with the learning experience, group collaboration, and effectiveness of the CAVE-enabled class from the learners. We also learned that the learners' learning experiences in CAVE could be further improved if we provided them with more learner-environment interaction, offered them a better sense of immersion, and reduced cybersickness. Implications of these findings are discussed.
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While layered metal oxides remain the dominant cathode materials for the state-of-the-art lithium-ion batteries, conversion-type cathodes such as sulfur present unique opportunities in developing cheaper, safer, and more energy-dense next-generation battery technologies. There has been remarkable progress in advancing the laboratory scale lithium-sulfur (Li-S) coin cells to a high level of performance. However, the relevant strategies cannot be readily translated to practical cell formats such as pouch cells and even battery pack. Here these key technical challenges are addressed by molecular engineering of the Li metal for hydrophobicization, fluorination and thus favorable anode chemistry. The introduced tris(2,4-di-tert-butylphenyl) phosphite (TBP) and tetrabutylammonium fluoride (TBA+F-) as well as cellulose membrane by rolling enables the formation of a functional thin layer that eliminates the vulnerability of Li metal towards the already demanding environment required (1.55% relative humidity) for cell production and gives rise to LiF-rich solid electrolyte interphase (SEI) to suppress dendrite growth. As a result, Li-S pouch cells assembled at a pilot production line survive 400 full charge/discharge cycles with an average Coulombic efficiency of 99.55% and impressive rate performance of 1.5 C. A cell-level energy density of 417 Wh kg-1 and power density of 2766 W kg-1 are also delivered via multilayer Li-S pouch cell. The Li-S battery pack can even power an unmanned aerial vehicle of 3 kg for a fairly long flight time. This work represents a big step forward acceleration in Li-S battery marketization for future energy storage featuring improved safety, sustainability, higher energy density as well as reduced cost.
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OBJECTIVE: Oral health-related quality of life (OHRQoL) is a multidimensional concept that is commonly used to examine the impact of oral health status on quality of life. The purpose of this study was to examine the optimal factor model of the Chinese version of the Oral Health Impact Profile (OHIP-14) questionnaire in clinical populations, measurement invariance across clinical status and gender cohorts. This would ensure equal validity of the Chinese version of OHIP-14 in different populations and further support public oral investigations. METHODS: The Chinese version of OHIP-14 was used to investigate 490 dental patients and 919 college students. Confirmatory factor analysis (CFA), item analysis and reliability, measurement invariance, and the t-test were used for data analyses. RESULTS: We found that the 7-factor structure had the best-fit index in the sample (CFI = 0.970, TLI = 0.952; SRMR = 0.029, RMSEA = 0.052(0.040,0.063)). The reliability of the scales was satisfactory (Cronbach's α = 0.942). The error variance invariance fitted the data adequately in measurement invariance, indicating that measurement invariance is acceptable both across the clinical and non-clinical populations (∆CFI=-0.017, ∆RMSEA = 0.010) and across genders in the clinical population (∆CFI = 0.000, ∆RMSEA=-0.003). T-test for scores showed that the clinical populations scored significantly higher than the non-clinical populations, as did the overall score (t = 7.046, p < 0.001, d = 0.396), in terms of functional limitation (t = 2.178, p = 0.030, d = 0.125), physical pain (t = 7.880, p < 0.001,d = 0.436), psychological discomfort (t = 8.993, p < 0.001, d = 0.514), physical disability (t = 6.343, p < 0.001, d = 0.358), psychological disability (t = 5.592, p < 0.001, d = 0.315), social disability (t = 5.301, p < 0.001,d = 0.304), social handicap (t = 4.452, p < 0.001, d = 0.253), and that in the non-clinical populations, females scored significantly higher than males, as did in terms of physical pain (t = 3.055, p = 0.002, d = 0.280), psychological discomfort (t = 2.478, p = 0.014, d = 0.222), and psychological disability (t = 2.067, p = 0.039, d = 0.188). CONCLUSION: This study found that the Chinese version of OHIP-14 has measurement invariance between the clinical and non-clinical populations and across genders in the clinical populations, and can be widely used in OHRQoL assessment for public oral investigations.
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Saúde Bucal , Qualidade de Vida , Humanos , Feminino , Masculino , Reprodutibilidade dos Testes , Povo Asiático , DorRESUMO
BACKGROUND: The Oral Health-related Quality of Life (OHRQoL) is a multi-dimensional concept commonly used to examine the impact of health status on quality of life, and the Oral Health Impact Profile-14 (OHIP-14) questionnaire is a good self-assessment tool. This study was designed to investigate the factor structure of the OHIP-14 scale Chinese version, measurement invariance and latent mean differences across genders among college students. METHODS: The online survey was completed by 919 college students. This study used confirmatory factor analysis (CFA) to check the structural models of the OHIP-14 scale, The correlation of each item with the scale total score could test homogeneity, and Cronbach's alpha (Cronbach's α) could evaluate internal consistency. Multi-group CFA was used to explore whether the Chinese version of the OHIP-14 scale was used in male and female populations for measurement consistency. T-test compared scores between men and women. Regression analyses were used to evaluate the relationship between age, gender, education, subject, and the score on the OHIP-14 scale. RESULTS: We found that the 7-factor structure had the best fit index in the sample. According to Cronbach's α, the overall score of OHIP was 0.958, and Cronbach's α for 7 factors was: functional limitation was 0.800, physical pain was 0.854, psychological discomfort was 0.902, physical disability was 0.850, psychological disability was 0.768, social disability was 0.862, social handicap was 0.819 and the test-retest reliability interval was 0.723. Multi-group confirmatory factor analysis supported residual measurement invariance across gender. T-test for scores showed that females scored higher significantly than men as did the overall score, in terms of physical pain (p<0.001), physical disability (p<0.001), and psychological disability (p<0.001). CONCLUSIONS: This study found the OHIP-14 Chinese version to be a good tool for assessing the college students' OHRQoL in China, allowing people to conduct self-assessments.
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Saúde Bucal , Qualidade de Vida , Feminino , Humanos , Masculino , Dor , Reprodutibilidade dos Testes , Estudantes , Inquéritos e QuestionáriosRESUMO
Mapping technique has been the powerful tool for the design of next-generation energy storage devices. Unlike the traditional ion-insertion based lithium batteries, the Li-S battery is based on the complex conversion reactions, which require more cooperation from mapping techniques to elucidate the underlying mechanism. Therefore, in this review, the representative works of mapping techniques for Li-S batteries are summarized, and categorized into the studies of lithium metal anode and sulfur cathode, with sub-sections based on shared characterization mechanisms. Due to specific features of mapping techniques, various aspects such as compositional distribution, in-plain/cross section characterization, coin cell/pouch cell configuration, and structural/mechanical analysis are emphasized in each study, aiming for the guidance for developing strategies to improve the battery performances. Benefited from the achieved progresses, suggestions for future studies based on mapping techniques are proposed to accelerate the development and commercialization of the Li-S battery.
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Lithium-sulfur battery promises great potential to promote the reform of energy storage field. Modified functional interlayer on separator has been recognized as efficient method to promote battery performances, mainly focusing on the entrapment and catalytic effect toward lithium polysulfide, while the mass transfer property across the interlayers has not been carefully considered. Herein, a dense layer composed of ion-inserted metal-organic frameworks is used to facilitate mass transfer across the layer and ensure high polysulfides entrapment efficiency. In situ Raman study reveals that the dense functional layer blocks the transfer of Li ions, while the ion-inserted layer can accelerate the ion-transfer kinetics and avoid the ion depletion caused polarization. As a result, a specific capacity of 742 mAh g-1 is obtained at 2 C, with the decay rate of 0.089% per cycle at 1 C over 600 cycles, demonstrating great potential for the application in advanced Li-S batteries.
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The aprotic lithium-oxygen (Li-O2) battery has triggered tremendous efforts for advanced energy storage due to the high energy density. However, realizing toroid-like Li2O2 deposition in low-donor-number (DN) solvents is still the intractable obstruction. Herein, a heterostructured NiS2/ZnIn2S4 is elaborately developed and investigated as a promising catalyst to regulate the Li2O2 deposition in low-DN solvents. The as-developed NiS2/ZnIn2S4 promotes interfacial electron transfer, regulates the adsorption energy of the reaction intermediates, and accelerates O-O bond cleavage, which are convincingly evidenced experimentally and theoretically. As a result, the toroid-like Li2O2 product is achieved in a Li-O2 battery with low-DN solvents via the solvation-mediated pathway, which demonstrates superb cyclability over 490 cycles and a high output capacity of 3682 mA h g-1. The interface engineering of heterostructure catalysts offers more possibilities for the realization of toroid-like Li2O2 in low-DN solvents, holding great promise in achieving practical applications of Li-O2 batteries as well as enlightening the material design in catalytic systems.