Spinel LiMn2O4 (LMO) is a state-of-the-art cathode material for Li-ion batteries. However, the operating voltage and battery life of spinel LMO needs to be improved for application in various modern ...technologies. Modifying the composition of the spinel LMO material alters its electronic structure, thereby increasing its operating voltage. Additionally, modifying the microstructure of the spinel LMO by controlling the size and distribution of the particles can improve its electrochemical properties. In this study, we elucidate the sol-gel synthesis mechanisms of two common types of sol-gels (modified and unmodified metal complexes)—chelate gel and organic polymeric gel—and investigate their structural and morphological properties and electrochemical performances. This study highlights that uniform distribution of cations during sol-gel formation is important for the growth of LMO crystals. Furthermore, a homogeneous multicomponent sol-gel, necessary to ensure that no conflicting morphologies and structures would degrade the electrochemical performances, can be obtained when the sol-gel has a polymer-like structure and uniformly bound ions; this can be achieved by using additional multifunctional reagents, namely cross-linkers.
Metal hydride beds will become essential components in the tritium plant for the safe handling and processing of tritium gases in nuclear fusion machines. Korea has been developing metal hydride beds ...focusing on robustness, reliability, and longevity. In this study, the authors designed an improved uranium hydride bed and fabricated an experimental bed with a storage capacity equivalent to 70 g of tritium based on our previous research efforts. We investigated the hydrogen and deuterium absorption characteristics of the experimental bed. After uranium was successfully activated by hydrogen, absorption performance experiments based on various operational conditions in the tritium plant were conducted. Full capacity absorption was performed with a different initial temperature of uranium and the time and rate for absorption were analyzed. We found that the different absorption rates between hydrogen and deuterium are related to the difference in equilibrium pressure between uranium hydride and uranium deuteride. These experimental results will be the basis of the operation mode development and performance reference for the uranium hydride bed in the fusion fuel cycle.
•Uranium bed of 70 g-T scale was developed for experimentation.•Perfomed hydrogen & deuterium absorption experiments at various initial temperature.•The ratio of H/D absorption rates is approximately 1.5.•Cooling target temperature is important for overall process time management.
Environmental concerns, especially global warming, have prompted efforts to reduce greenhouse gas emissions. Healthcare systems, including anesthesia practices, contribute to these emissions. ...Inhalation anesthetics have a significant environmental impact, with desflurane being the most concerning because of its high global warming potential. This study aimed to educate anesthesiologists on the environmental impact of inhalation anesthetics and assess changes in awareness and practice patterns, specifically reducing desflurane use. This study included data from patients who underwent surgery under general anesthesia 1 month before and after education on the effects of inhalation anesthetics on global warming. The primary endpoint was a change in inhalational anesthetic use. Secondary endpoints included changes in carbon dioxide equivalent (CO2e) emissions, driving equivalent, and medical costs. After the education, desflurane use decreased by 50%, whereas sevoflurane use increased by 50%. This shift resulted in a reduction in the overall amount of inhalational anesthetics used. The total CO2e and driving-equivalent values decreased significantly. The cost per anesthesia case decreased, albeit to a lesser extent than expected. Education on the environmental impact of inhalation anesthetics has successfully altered anesthesiologists' practice patterns, leading to reduced desflurane usage. This change has resulted in decreased CO2e emissions and has had a positive effect on mitigating global warming. However, further research is required to assess the long-term impact of such education and the variability in practice patterns across different institutions.
Abstract
This study describes the Korea Meteorological Administration/National Institute of Meteorological Sciences (KMA/NIMS) Atmospheric Research Aircraft (NARA) and its observational data archive. ...NARA has been performing annual observation flights, which are aimed at reducing the uncertainty of atmospheric observations in the observation data gap area around the Korean peninsula, since January 2018. An online system has also been constructed to provide data management, transmission, quality control and simple visualization. The mission strategy of NARA is subdivided into four individual units, namely observations of severe weather (SW), climate monitoring (CM), environmental monitoring (EM) and cloud physics and weather modification experiments (CP). As of December 2020, NARA has been launched operationally for 325 flights (corresponding to 9.02 flights per month), typically over the West Sea, mid‐inland areas (34.4% and 25.4%, respectively), and below an altitude of 3 km (51.9%). Results of intercomparison tests confirmed that NARA measurements have reasonable offsets (<0.9%) to each other in terms of pressure and temperature. Moreover, the monthly average temperature profile in the East Sea area showed a seasonal variation was detected in monthly variation. From these results, it is evident that NARA data will contribute significantly to enhancing the level of scientific understanding of atmospheric observations and the applications (i.e. long‐term study) thereof as the amount of data accumulated increases.
Sn-based lead-free solders such as Sn-Ag-Cu, Sn-Cu, and Sn-Bi have been used extensively for a long time in the electronic packaging field. Recently, low-temperature Sn-Bi solder alloys attract much ...attention from industries for flexible printed circuit board (FPCB) applications. Low melting temperatures of Sn-Bi solders avoid warpage wherein printed circuit board and electronic parts deform or deviate from the initial state due to their thermal mismatch during soldering. However, the addition of alloying elements and nanoparticles Sn-Bi solders improves the melting temperature, wettability, microstructure, and mechanical properties. Improving the brittleness of the eutectic Sn-58wt%Bi solder alloy by grain refinement of the Bi-phase becomes a hot topic. In this paper, literature studies about melting temperature, microstructure, inter-metallic thickness, and mechanical properties of Sn-Bi solder alloys upon alloying and nanoparticle addition are reviewed.
Epilepsy, characterized by recurrent unprovoked seizures, poses significant challenges to affected individuals globally. While several established risk factors for epilepsy exist, the association ...with cigarette smoking remains debated. This study aims to conduct systematic review and meta-analysis to elucidate the potential association between smoking and the likelihood of epilepsy.
The search was performed on March 31st, 2023, using the Medline, Embase, Web of Science, Scopus, and ScienceDirect. We included cohort, cross-sectional, and case-control studies in our meta-analysis, conducting subgroup analyses based on smoking history, sex, and epilepsy type to yield specific insights.
We identified 2550 studies, of which 17 studies were finally included in this study. The pooled odds ratio of epilepsy was 1.14 (0.96-1.36) in smokers compared to non-smokers. In current smokers compared to non-smokers, the odds ratio was 1.46 (1.13-1.89), while, in former smokers compared to non-smokers, the odds ratio was 1.14 (0.83-1.56).
While the overall association between smoking and epilepsy did not reach statistical significance, a notable association was found among current smokers. The study emphasizes the importance of smoking cessation as a potential preventive measure against epilepsy, especially given the proconvulsive effects of nicotine. Future research should address limitations and explore specific clinical scenarios to enhance our understanding of the complex relationship between cigarette use and epilepsy.
CRD42022342510.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In situprobing of surface species and incipient phases is vital to unraveling the mechanisms of chemical and energy transformation processes. Here we report Ag nanoparticles coated with a thin-film ...SiO sub(2) shell that demonstrate excellent thermal robustness and chemical stability for surface enhanced Raman spectroscopy (SERS) study of solid oxide fuel cell materials under in situconditions (at similar to 400 degree C).
Background Epilepsy, characterized by recurrent unprovoked seizures, poses significant challenges to affected individuals globally. While several established risk factors for epilepsy exist, the ...association with cigarette smoking remains debated. This study aims to conduct systematic review and meta-analysis to elucidate the potential association between smoking and the likelihood of epilepsy. Methods The search was performed on March 31st, 2023, using the Medline, Embase, Web of Science, Scopus, and ScienceDirect. We included cohort, cross-sectional, and case-control studies in our meta-analysis, conducting subgroup analyses based on smoking history, sex, and epilepsy type to yield specific insights. Results We identified 2550 studies, of which 17 studies were finally included in this study. The pooled odds ratio of epilepsy was 1.14 (0.96-1.36) in smokers compared to non-smokers. In current smokers compared to non-smokers, the odds ratio was 1.46 (1.13-1.89), while, in former smokers compared to non-smokers, the odds ratio was 1.14 (0.83-1.56). Conclusions While the overall association between smoking and epilepsy did not reach statistical significance, a notable association was found among current smokers. The study emphasizes the importance of smoking cessation as a potential preventive measure against epilepsy, especially given the proconvulsive effects of nicotine. Future research should address limitations and explore specific clinical scenarios to enhance our understanding of the complex relationship between cigarette use and epilepsy. Systematic review registration CRD42022342510. Keywords: Smoking, Nicotine, Epilepsy, Seizure, Systematic review, Meta-analysis
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The most important purpose of the tritium processes in the fusion fuel cycle is to stably supply tritium and deuterium to reduce operational uncertainty in the Tokamak. To achieve this, it is ...desirable for the process operation to be designed as a continuous process with a steady flowrate, pressure and composition. In this study, we aim to propose a modified concept of storage and delivery system, the Fuel Buffer System which is the main interface system between the tritium processing systems and Tokamak for the continuous operation in tritium processes. The buffer vessel is considered as a key interface equipment in the FBS to make steady feed or product stream. We evaluate the tritium inventory and the design impact of the FBS in a tokamak burn-and-dwell operating environment. By applying known ITER operating scenarios, we perform sensitivity analysis on the operating pressure of the buffer vessel and fuel cycle operation time. Based on the results, we suggest the design strategy for fusion fuel cycle in the K-DEMO.
PDF
