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The massive amount of text related to education provides rich information to support education in many aspects. In the meantime, the vast yet increasing volume of text makes it impossible to analyze manually. Text mining is a powerful tool to automatically analyze large-scaled texts and generate insights from the texts. However, many educational scholars are not fully aware of whether text mining is useful and how to use it in their studies. To address this problem, we reviewed the literature to examine the educational research that used text mining techniques. Specifically, we proposed an educational text mining workflow and focused on identifying the articles' bibliographic information, research methodologies, and applications in alignment with the workflow. We selected 161 articles published in educational journals from 2015 to 2020. We find that text mining is becoming more popular and essential in educational research. The conclusion is that we can employ three steps (text source selection, text mining techniques application, and educational information discovery) to use text mining in educational studies. We also summarize different options in each step in this paper. Our work should help educational scholars better understand educational text mining and provide support information for future research in text mining for educational contexts.

This mixed-methods study explored K-12 teachers' feelings, experiences, and perspectives regarding online teaching during the COVID-19 pandemic. The study also examined teachers' perspectives of the "new normal" after COVID-19 and of what should be done to better prepare teachers for future emergencies. Both quantitative and qualitative data were collected from an online survey and follow-up interviews. A total of 107 teachers from 25 different states in the United States completed the online survey, and 13 teachers from 10 different states participated in the follow-up interviews. The results revealed teachers' feelings about online teaching and various strategies and tools they used during the early stage of the COVID-19 pandemic. The major challenges faced by teachers during the pandemic included lack of student participation and engagement (or lack of parental support), students without access to technology, concerns about students' well-being, no face-to-face interactions with students, no work-life balance, and learning new technology. Four major themes emerged regarding how to better prepare teachers for future emergencies: (1) professional development for online learning, (2) technology access, (3) technology training for both teachers and students, and (4) action plans and communication. Regarding teachers' perspectives of the "new normal," five major themes emerged: (1) more online or blended learning, (2) rethinking normal, (3) hygiene and social distancing, (4) smaller classes and different school schedules, and (5) uncertainty and concerns about the "new normal."

Preparing for back-to-school is essential, and it is also complicated because it involves different groups of people, and they have different needs. Pandemics, like COVID-19, make the situation even more difficult. Better preparation during a pandemic needs a comprehensive understanding of the situation. However, few studies have provided such information, especially during a pandemic. Furthermore, traditional research methods can hardly address the problems. This paper used text mining approaches to interpret open Twitter discussions on back-to-school preparation during COVID-19 and generated an inclusive insight into the preparation. Specifically, we collected 26,219 related tweets and analyzed the user profile descriptions to determine who was involved in the preparation. We also examined the most frequently retweeted tweets and conducted a topic modeling analysis to find people's concerns. Our research provides a holistic view of preparation for back-to-school during the pandemic, and it could help better prepare for back-to-school in the future pandemic.

Although hexagonal boron nitride (h‐BN) was initially considered a less promising photocatalyst due to its large band gap and apparent chemical inertness, its unique two‐dimensional lamellar structure coupled with high stability and environmental friendliness, as the second largest van der Waals material after graphene, provides a unique platform for photocatalytic innovation. This review not only highlights the intrinsic qualities of h‐BN with photocatalytic potentials, such as high stability, environmental compatibility, and tunable bandgap through various modification strategies but also provides a comprehensive overview of the recent advances in h‐BN‐based nanomaterials for environmental and energy applications, as well as an in‐depth description of the modification methods and fundamental properties for these applications. In addition, we discuss the challenges and prospects of h‐BN‐based nanomaterials for future photocatalysis. [ABSTRACT FROM AUTHOR]

The cycling stability of O3‐type NaNi1/3Fe1/3Mn1/3O2 (NFM) as a commercial cathode material for sodium ion batteries (SIBs) is still a challenge. In this study, the Ni/Fe/Mn elements are replaced successfully with tantalum (Ta) in the NFM lattice, which generated additional delocalized electrons and enhanced the binding ability between the transition metal and oxygen, resulting in suppressed lattice distortion during charging and discharging. This caused significant mitigation of voltage decay and improved cycle stability within the potential range of 2.0–4.2 V. The optimized Na(Ni1/3Fe1/3Mn1/3)0.97Ta0.03O2 sample achieved a reversible capacity of 162.6 mAh g−1 at a current rate of 0.1 C and 73.2 mAh g−1 at a high rate of 10 C. Additionally, the average charge/discharge potential retention reached 98% after 100 cycles, significantly mitigating the voltage decay. This work demonstrates a significant contribution towards the practical utilization of NFM cathodes in the SIBs energy storage field. [ABSTRACT FROM AUTHOR]

The practical application of sodium (Na) metal anode has been seriously hindered by the uncontrolled Na dendrite growth and severe volume expansion inducing short battery lifespan and safety concerns. Here, highly sodiophilic and ultrafine ZnS‐modified carbon fibers have been rationally constructed as a scaffold to obviate these drawbacks. The in situ generated Na2S‐reinforced fast ion transport interphase and the effective space confinement synergistically facilitate the fast sodium ion interfacial transfer and the homogeneous and dendrite‐free Na deposition, thus enabling high‐rate and dendrite‐free Na metal anode. The modified Na metal demonstrates ultrahigh rate capability (15 mA cm−2) and ultralong cycling life (5300 cycles). Moreover, the Na|Na3V2(PO4)3 (NVP) cell delivers ultrahigh rate capability (80 C) and extraordinarily ultralong lifespan cycling durability (2980 cycles). The Na|NVP pouch cell also exhibits an extraordinarily ultralong‐term cycle life of over 1070 cycles with an extremely low capacity decay rate of 0.0088% per cycle at 10 C. This work provides a facile and efficient strategy to propel the Na metal anode towards practicability. [ABSTRACT FROM AUTHOR]

The practical utilization of Li metal anodes has been significantly plagued by the challenges of uncontrollable dendritic Li growth and poor interphase instability. Here, the study reports a novel strategy to strengthen interphase and give highly efficient active seeds concurrently to stabilize Li metal via a highly lithiophilic In2O3 decorated porous scaffold. In situ configurated fast‐ion‐transport Li2O‐strengthened interphase layer cooperatively with highly efficient Li13In3 nucleation induction can endow the uniform Li nucleation/growth and high Li utilization efficiency. As a result, the achieved modified Li metal manifests high Coulombic efficiency, ultrahigh rate performance (5 mA cm−2), and ultra‐long lifespan cycling durability (7975 cycles). Importantly, the established Li|LiFePO4 cells exhibit long‐term cycling durability over 600 cycles at 1 C with an ultralow decay rate of ca. 0.017% per cycle. Moreover, the Li|LiCoO2 pouch cells with ultrahigh areal capacity of ca. 3.89 mAh cm−2 also exhibit extraordinarily prolonged cycling performance with excellent capacity retention despite extremely harsh cycling conditions of low negative‐to‐positive‐capacity (N/P) ratio of ca. 1.7 and lean electrolyte of ca. 4.9 g Ah−1. This work enlightens a facile and effective avenue toward highly stable Li metal anode toward reliable practicability. [ABSTRACT FROM AUTHOR]