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1.
Front Psychol ; 14: 1165332, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37771809

RESUMO

Introduction: In recent years, the widespread shift toward online learning in higher education has led to a notable increase in the utilization of collaborative mobile-assisted language learning (MALL). However, the efficacy and implementation of MALL in college settings remain subjects of ongoing scholarly debate. To gain deeper insights into the experiences of Chinese college students with collaborative MALL and investigate factors that may influence their intentions for further adoption, this study proposed a comprehensive model that integrates the updated Unified Theory of Acceptance and Use of Technology (UTAUT) and flow theory. Methods: The model aimed to assess the relationship between flow and various antecedents, including perceived cost, social influences, perceived mobility, collaboration, and knowledge sharing, which shape students' intentions to adopt collaborative MALL. A survey was conducted among a sample of 831 students from 32 provinces and autonomous regions. Results: The data analysis revealed that while 73% of participants reported having experienced collaborative MALL, overall adoption levels among Chinese college students are still in its initiative stage of adoption. Furthermore, variations were observed in the experiences of students from different majors and level of education. Importantly, the assessment of the proposed Mobile Collaborative Language Learning (MCLL) Model demonstrated the significant role of flow in predicting the adoption of collaborative MALL among Chinese college students. Discussion: The study concludes with suggestions for future research opportunities based on the research findings, aiming to enhance our understanding and application of collaborative MALL in higher education contexts.

2.
ACS Omega ; 6(39): 25518-25528, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34632209

RESUMO

To solve the problem of heavy oil demulsification difficulties in Liaohe Oilfield, phenolamine resin initiator was synthesized from p-trifluoromethyl phenol, and then FB series fluorinated polyether demulsifiers were synthesized by block polymerization using ethylene oxide (EO) and propylene oxide (PO) as raw materials. The demulsifiers were characterized by infrared spectroscopy, cloud point, hydrophilic-lipophilic balance (HLB) value, and surface tension. The demulsifying and dehydrating properties were tested by demulsifying and dehydrating experiments, the demulsification mechanism was analyzed by the microscopic demulsification process test, and the influence of demulsifier addition and demulsifying temperature on demulsifying performance was also studied. The results showed that under the condition of the optimum demulsification temperature of 60 °C and the optimum demulsifier dosage of 100 mg/L, the water removal (%) of fluorinated polyether demulsifier of FB 4 was the highest, and the overall water removal (%) of 50 mL crude oil emulsion in Liaohe Oilfield reached 90.33% within 2 h, which was better than the current demulsifier used in Liaohe crude oil.

3.
ACS Omega ; 6(15): 10454-10461, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-34056198

RESUMO

Various flooding technologies were applied in the middle and late stages of the oilfield, which made the heavy oil emulsion receive much concern because of its high stability and separation difficulty. In our paper, alcohol molecules were used as initiators and multibranched block copolymers were synthesized through open-loop polymerization technology. A variety of novel modified block polyether demulsifiers with demulsification activity were finally synthesized through water-soluble modification and oil-soluble modification, which achieved efficient demulsification of heavy oil emulsions. Hydrophile-lipophile balance (HLB) values and surface tension were used to characterize demulsifiers. In addition, their demulsification efficiency was evaluated by measuring the amount of dehydration in the separated heavy oil emulsion experiments. The experimental results showed that within 5 h, the demulsification effect of the water-soluble demulsifier is better than that of the oil-soluble demulsifier. When the HLB value of the demulsifier reaches a certain value, the dehydration rate and the demulsification effect reach the highest point. When the amount of demulsifier is 50 µg/g and the demulsification temperature is 85 °C, the dehydration rate of the water-soluble demulsifier X-6 reached 91%, the water quality was clear, and the demulsification effect reached its peak. This work will provide a novel and efficient demulsifier for demulsification and dehydration of heavy oil emulsions.

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