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Is safety education in the E-learning environment effective? Factors affecting the learning outcomes of online laboratory safety education
No full textSafety education is essential to prevent accidents and casualties in modern society. The coronavirus disease (COVID-19) pandemic has increased the importance of e-learning in safety education. However, there is limited research on the effectiveness of this type of education. This study aims to develop a model that predicts the factors affecting the learning outcomes of safety education in an e-learning environment. An online survey of research workers who participated in laboratory safety education at a university was conducted to empirically test the developed model. Partial least squares-based structural equation modeling (PLS-SEM) was used for analysis and hypothesis testing. Face-to-face interviews were conducted to supplement the findings. The results revealed the following. (1) Intention to use online laboratory safety education (OLSE) was significantly and positively predicted by attitude toward online education and satisfaction, but not by attitude toward safety education. (2) Respondents preferred safety education through e-learning not because of its effectiveness, but to avoid the stress and inconvenience of traditional training. (3) Negative perceptions of education and lack of motivation to learn are the root causes of low effectiveness. The findings revealed the current status of OLSE with deficient learning effects and learners' negative perceptions. This study identifies the adverse effects of mandatory safety education in e-learning environments. This study provides insights into the low effectiveness of mandated online safety education and argues for the need to increase learner motivation and improve legislation. We suggest several practical implications to improve the effectiveness of such education
Wide-temperature-range operation of lithium-metal batteries using partially and weakly solvating liquid electrolytes
No full textThe optimal design of liquid electrolytes is vital for the build-up of long-lifespan lithium-metal batteries (LMBs) that function over a wide-temperature-range. Tuning the electrolyte solvation-structure using partially-fluorinated ether solvents and constructing stable electrode-electrolyte interfaces using electrolyte additives enhance the electrochemical reversibility of lithium-metal anodes and facilitate the realization of high-capacity cathodes for LMBs. This study reports a partially and weakly solvating electrolyte (PWSE) which enables the stable cycling of LMBs at high-voltages within a wide-temperature range through modulation of an electrolyte local-environment using a low-salt concentration of 1.3 M. 1,2-Bis(1,1,2,2-tetrafluoroethoxy)ethane contains two oxygen atoms that coordinate weakly with Li+-ions; it transforms the 1,2-dimethoxyethane-dominated electrolyte solvation-structure to a more anion-incorporated structure. Moreover, a combination of lithium fluoromalonato(difluoro)borate and silver nitrate strengthens the electrode-electrolyte interfaces and improves the oxidation durability of ether-based electrolytes. The PWSE enables the construction of 4.4 V Li|LiCoO2 full cells with a long-lifespan and high-areal-capacity of 3.12 mA h cm-2. With the aid of electrolyte additives, a partially and weakly solvating electrolyte which is acquired by controlling the local environment of the electrolyte qualifies the stable cycling of LMBs at high voltages over a wide temperature range
Highly Sensitive Plasmonic Terahertz Detector with Integrated Sub-Wavelength Aperture Based on Asymmetric FET in 65-nm CMOS Technology
No full textWe have analyzed the effect of structural asymmetry and aperture position for field-effect transistor (FET)-based plasmonic terahertz (THz) detector with integrated aperture by using 65-nm CMOS process. By applying structural asymmetry between the source and drain in FET, we obtained 9.3 mV (7-fold) photoresponse (?? u) in comparison to symmetric FET for aperture positioned at gate. In addition, by asymmetry in feeding the incoming THz wave with aperture positioned at drain, we have experimentally demonstrated highly enhanced detection performance followed by 18.5 mV (2-fold) ?? u in comparison to aperture positioned at gate
Unveiling the electrochemical characteristics of acetonitrile-catholyte-based Na-CO2 battery
No full textThe development of metal-CO2 batteries has attracted intense attention because of their unique electrochemical reaction for utilization of CO2 gas. However, unlike the alkali metal-based O2 batteries, a limited number of combinations of aprotic electrolytes have been employed for Li(Na)???CO2 batteries due to the sluggish reaction for the formation of the Li(Na)2CO3 discharge product. Here, we demonstrate an acetonitrile (MeCN)-based catholyte for use in a hybrid cell type Na-CO2 battery. The presence of a solid ceramic separator in our hybrid cell allows the stable operation of the MeCN catholyte-based Na-CO2 battery, resulting in improved electrochemical characteristics such as low overpotential, high energy density, and long cycle stability compared to the conventional TEGDME-based electrolyte. In particular, results of molecular dynamics simulations suggest that the improved performance is mainly due to the enhanced Na+ diffusion in the electrolyte. The calculated barrier for Na+ diffusion in MeCN is approximately four times lower than that in TEGDME. Thus, this work provides a promising electrolyte combination and reveals the mechanism for the improved performance of the MeCN-based electrolyte used in the hybrid cell structure, promoting the development of Na-CO2 batteries as practical secondary energy storage devic
Construction of prophage-free and highly-transformable <i>Limosilactobacillus reuteri</i> strains and their use for production of 1,3-propanediol
No full textThe lactic acid bacterium Limosilactobacillus reuteri (formerly Lactobacillus reuteri) is a desirable host for the production of 1,3-propanediol (1,3-PDO) from glycerol when 1,3-PDO is used in the food or cosmetic industry. However, the production is hindered by strain instability, causing cell lysis, and difficult gene manipulation. This study reveals that the stability of L. reuteri DSM 20016 and its 1,3-PDO production, especially in the alcohol dehydrogenases (ADHs)-deletion mutants, are greatly enhanced after the deletion of two prophages (Phi 3 and Phi 4) present in the L. reuteri's chromosome. The resulting phage-free and ADHs-deletion mutant could produce >825 mM 1,3-PDO in 48 h without cell lysis at the theoretical maximum yield on glucose of similar to 2 mol/mol. Compared to the wild-type strain, the mutant exhibited a 45.2% increase in 1,3-PDO production titer and a 2.1-fold increase in yield. In addition, this study reports that the transformation efficiency of L. reuteri Delta adh2 Delta adh6 bmutant strains were greatly enhanced by >300-fold after the deletion of prophage 03, probably due to the removal of a restriction-modification (RM) system which resides in the phage genome. With improved stability and higher transformation efficiency, recombinant L. reuteri DSM 20016 Delta adh2 Delta adh6 Delta Phi 3 Delta Phi 4 can be a more reliable and amenable host for industrial applications
An Enhanced Sampling Approach for Computing the Free Energy of Solid Surface and Solid-Liquid Interface
No full textFree energies of a solid surface and a solid-liquid interface play significant roles in thermodynamics. Due to the limited availability of experimental data, computational methods offer effective alternatives for calculating these properties. This study adopts advanced frameworks of the logarithmic mean force dynamics method to present an enhanced sampling approach for the calculation of the free energy at different temperatures. To achieve this, the free energy profile is constructed along with a pre-established collective variable within the melting transition and cleavage processes. The values of the solid surface and solid-liquid interface free energies are then extrapolated from the excess free energy related to the formation and persistence of the solid surface or the solid-liquid interface. Furthermore, this methodology is employed to calculate the temperature dependence of the free energy measurements for the (100) and (110) surfaces and interfaces of Cu. It is shown that this methodology is robust and readily applicable in contemporary models of atomic interactions and various systems. A generalized but as simple as possible approach that can be applied to compute both the free energy of the solid-liquid interface and the solid surface is presented. The approach is based on enhanced sampling methods that can compute the interfacial free energy at various temperatures, orientations, and across a wide range of systems.imag
Reconstruction of interactions in the ProtoDUNE-SP detector with Pandora
No full textThe Pandora Software Development Kit and algorithm libraries provide pattern-recognition logic essential to the reconstruction of particle interactions in liquid argon time projection chamber detectors. Pandora is the primary event reconstruction software used at ProtoDUNE-SP, a prototype for the Deep Underground Neutrino Experiment far detector. ProtoDUNE-SP, located at CERN, is exposed to a charged-particle test beam. This paper gives an overview of the Pandora reconstruction algorithms and how they have been tailored for use at ProtoDUNE-SP. In complex events with numerous cosmic-ray and beam background particles, the simulated reconstruction and identification efficiency for triggered test-beam particles is above 80% for the majority of particle type and beam momentum combinations. Specifically, simulated 1 GeV/c charged pions and protons are correctly reconstructed and identified with efficiencies of 86.1 ?? 0.6 % and 84.1 ?? 0.6 %, respectively. The efficiencies measured for test-beam data are shown to be within 5% of those predicted by the simulation
Solid Additive Delicately Controls Morphology Formation and Enables High-Performance in Organic Solar Cells
No full textVolatile solid additives are an effective strategy for optimizing morphology and improving the power conversion efficiencies (PCEs) of organic solar cells (OSCs). Much research has been conducted to understand the role of solid additives in active layer morphology. However, it is crucial to delve deeper and understand how solid additives affect the entire morphology evolution process, from the solution state to the film state and the thermal annealing stage, which remains unclear. Herein, the use of a highly crystalline solid additive, phenoxathiin (Ph), in D18-Cl:N3-based OSCs and study its impact on morphology formation and photovoltaic performance is presented. Owing to its good miscibility with the acceptor N3, Ph additive can not only extend the time for the active layer to form from the solution state to the film state, but also provide sufficient time for acceptor aggregation. After thermal annealing, Ph solid additive volatilizes better aligned the N3 molecules and formed a favorable hybrid morphology. Consequently, the D18-Cl:N3-based OSC exhibited an outstanding PCE of 18.47%, with an enhanced short-circuit current of 27.50 mA cm(-2) and a fill factor of 77.82%. This research is spurring the development of high-performance OSCs using solid additives that allow fine control during morphology development