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Li-CO2 batteries (LCBs) have emerged as promising solutions for energy storage, with the added benefit of contributing to carbon neutrality by capturing and utilizing CO2 during operation. In this study, a high-performance LCB was developed using a Ge-doped LiAlGeTi (PO4)3 (LAGTP) solid electrolyte, which was synthesized via a solution-based method by doping Ge into NASICON-type LATP. The ionic conductivity of the LAGTP pellets was measured as 1.04 × 10−3 S/cm at 25 °C. The LCB utilizing LAGTP and an MWCNT/Ru cathode maintained a stable cycling performance over 200 cycles at a current density of 100 mA/g, with a cut-off capacity of 500 mAh/g. Post-cycle analysis confirmed the reversible electrochemical reactions at the cathode. The integration of LAGTP as a solid electrolyte effectively enhanced the ionic conductivity and improved the cycle life and performance of the LCB. This study highlights the potential of Ge-doped NASICON-type solid electrolytes for advanced energy-storage technologies and offers a pathway for developing sustainable and high-performance LCBs.

Li–S batteries are promising large-scale energy storage systems but currently suffer from performance issues; a major reason is the dissolution of polysulfides in electrolytes. To this end, we report a high-energy-density Lithium–Sulfur (Li–S) battery that combines a catholyte and a sulfur-free carbon nanofiber (CNF) cathode. The cathode was synthesized by carbonizing binder-free polyacrylonitrile (PAN) nanofibers, affording a high surface area. In the catholyte, added polysulfides acted as both conductive Li salts and active materials. Investigating the electrochemical performance of this concept in both Swagelok- and pouch-type cells afforded energy densities exceeding 3 mAh cm−2 at a discharge rate of 0.1 C. This combination could also be utilized in high-capacity pouch cells with capacities of up to 250 mAh g−1. Both cell types exhibited good cycle performance. Adding LiNO3 to the electrolyte suppressed the redox shuttle reactions. Moreover, the cathode being binder-free increased the energy density and simplified cathode fabrication. Characterizing the cathode before and after cycling revealed that deposition was reversible, and that cell reactions at least partially formed sulfur as the end product, resulting in high sulfur amounts in the cell. We expect our concept to greatly aid in the development of practically applicable Li–S cells.

We developed an automated microregistration method that enables repeated in vivo skin microscopy imaging of the same tissue microlocation and specific cells over a long period of days and weeks with unprecedented precision. Applying this method in conjunction with an in vivo multimodality multiphoton microscope, the behavior of human skin cells such as cell proliferation, melanin upward migration, blood flow dynamics, and epidermal thickness adaptation can be recorded over time, facilitating quantitative cellular dynamics analysis. We demonstrated the usefulness of this method in a skin biology study by successfully monitoring skin cellular responses for a period of two weeks following an acute exposure to ultraviolet light.

Objectives A water treatment system, combining aeration and reverse osmosis (RO) processes, was introduced to improve water supply facilities in a small village where additional water treatment was required due to high concentrations of natural radioactive substances, nitrate nitrogen, and fluoride. In this study, CCRO(Closed-circuit reverse osmosis) was first introduced for commercial use in Korea. With this system, we evaluated its water treatment efficiency and effectiveness of blending the aerated water and RO permeate for improved waterworks in rural areas. Methods The removal rate of major pollutants and other ionic substances was evaluated by analyzing the water quality of raw water and unit processes. In addition, the operational efficiency of a small-scale water supply facility was verified and optimized by evaluating a change in operational characteristics depending on the blending ratio of the treated waters by aeration and CCRO processes. Results and Discussion Up to 86% of the radon contained in raw water was removed by the aeration process within 2 hours, and 98.9% of uranium, 85.5% of nitrate nitrogen, and 82.8% of fluoride were removed by the RO process. In the case of other ionic substances, more than 80% was removed on average by the RO process. The higher blending ratio of RO permeate up to 75% resulted in the better quality of the final treated water. However, since requiring the high flux and pressure (at 1.8 m3/hr and 7.6 bar, respectively), CCRO operation resulted in a relatively high specific power consumption at 0.27 kWh/m3. Conclusion In this study, we found that the major contaminants (natural radioactive substances, nitrate nitrogen, and fluoride) were effectively removed by the water treatment system wherein the aeration and CCRO processes were combined. In particular, it was confirmed for the first time in Korea that the stable operation and water treatment efficiency of the CCRO process was satisfactory for commercial purposes. It could produce high-quality tap water through the blending of waters treated by aeration and CCRO, expecting that meeting drinking-water quality standards would be attainable even when raw water contains high-concentration pollutants.

Commercial Li-ion batteries are vital to our daily lives, powering everything from portable devices to high-powered electric vehicles. The current usage of flammable liquid electrolytes in conventional Li-ion batteries creates risks, necessitating the development of solid electrolytes that are secure and reliable. However, the ionic conductivity of solid electrolytes cannot compete with liquid electrolytes. Herein, we report the synthesis of Li1·5Al0·3Si0·2Ti1·7P2·8O12 (LASTP) powder with improved ionic conductivity and evaluate its performance as a solid electrolyte in an all-solid-state battery (ASSB). A facile solution-based method is used for the LASTP synthesis with optimized sintering and calcination temperatures. As a result, the LASTP sintered at 1050 °C has the highest relative density (96.84%) and ionic conductivity (9.455 × 10−4 S/cm) with the lowest activation energy (Ea, 0.226 eV). A coin cell is assembled with Li/LASTP/Li(Ni0·65Co0·15Mn0.20)O2 all-solid-state configuration to evaluate the electrochemical performance. In addition, an electrospun polymer conductor film (PVDF-HFP) is added between the electrodes and the solid electrolyte to reduce the interfacial resistance. The ASSB has shown a stable and high performance with remarkable discharge capacity (205.3 mAh/g) at 0.1C and could be operated even after 100 cycles with 85.3% of retention at 0.2C. Therefore, the present work suggests that the LASTP solid electrolyte is a promising material for next-generation safe ASSBs.

Commercial lithium-ion batteries using liquid electrolytes are still a safety hazard due to their poor chemical stability and other severe problems, such as electrolyte leakage and low thermal stability. To mitigate these critical issues, solid electrolytes are introduced. However, solid electrolytes have low ionic conductivity and inferior power density. This study reports the optimization of the synthesis of sodium superionic conductor-type Li1.5Al0.3Si0.2Ti1.7P2.8O12 (LASTP) solid electrolyte. The as-prepared powder was calcined at 650 °C, 700 °C, 750 °C, and 800 °C to optimize the synthesis conditions and yield high-quality LASTP powders. Later, LASTP was sintered at 950 °C, 1000 °C, 1050 °C, and 1100 °C to study the dependence of the relative density and ionic conductivity on the sintering temperature. Morphological changes were analyzed using field-emission scanning electron microscopy (FE-SEM), and structural changes were characterized using X-ray diffraction (XRD). Further, the ionic conductivity was measured using electrochemical impedance spectroscopy (EIS). Sintering at 1050 °C resulted in a high relative density and the highest ionic conductivity (9.455 × 10−4 S cm−1). These findings corroborate with the activation energies that are calculated using the Arrhenius plot. Therefore, the as-synthesized superionic LASTP solid electrolytes can be used to design high-performance and safe all-solid-state batteries.

This study reports an integrated device of a lithium-ion battery (LIB) connected with Si solar cells. A Li(Ni0.65Co0.15Mn0.20)O2 (NCM) cathode and a graphite (G) anode were used to fabricate the lithium-ion battery (LIB). The surface and shape morphologies of NCM and graphite powder were characterized by field emission scanning electron microscopy (FE-SEM). The structural properties of NCM and graphite powder were determined by X-ray diffraction (XRD) analysis. XRD patterns of powders were well matched with those of JCPDS data. To investigate the electrochemical characteristics of NCM and graphite, cycling tests were performed after assembling the NCM-Li, the G-Li half-cell, and the NCM-G full-cell. The discharge capacity of the NCM cathode at 0.1C was 189.82 mAh/g−1. The NCM-graphite full-cell showed 98.25% cycle retention at 1C after 50 cycles. To obtain enough charging voltage for the LIB connected with solar cells in an integrated device, eight single Si solar cells were connected in a series. The short-circuit photocurrent density for Si solar cells was 4.124 mA/cm2. The fill factor and the open circuit voltage were 0.78 and 4.5 V, respectively. These Si solar cells showed a power conversion efficiency of 14.45%. The power conversion andstorage efficiency of the integrated device of the NCM battery and Si solar cells was 7.74%. Charging of the integrated device could be as effective as charging with a battery cycler.

This study aimed to determine the changes in the local fiscal structure brought about by the change in the transaction tax, including the acquisition tax, by the central government. The review of the analysis results proved the following. First, the government’s transaction tax exemption policy effectively influenced the expansion of the local fiscal budget. Transaction tax exemptions such as acquisition tax exemptions would not contribute to the expansion of the local fiscal budget in the short run, but may do so in the long run. Second, the review of the effect of the transaction tax exemption policy by the central government on the local fiscal structure confirmed that its impact on the local fiscal structure may vary depending on the timing of such tax exemption. Third, the overall local fiscal structure as a result of the transaction tax exemption by the central government was confirmed to have been influenced more by the fiscal capability of the local government than by the income level of the local residents. In conclusion, the stimulation of real estate transactions using tax tools may positively influence the overall fiscal structure of local governments, but it would also put pressure on the fiscal management of local governments because it is largely influenced by the fiscal capability of the local governments.

This study demonstrates the use of perovskite solar cells for fabrication of self-charging lithium-ion batteries (LIBs). A LiFePO4 (LFP) cathode and Li4Ti5O12 (LTO) anode were used to fabricate a LIB. The surface morphologies of the LiFePO4 and Li4Ti5O12 powders were examined using field emission scanning electron microscopy. The structural properties of the two powders were investigated using X-ray diffraction. The electrochemical properties of the LiFePO4-Li and Li4Ti5O12-Li half cells and of the full cell were investigated. The LiFePO4-Li4Ti5O12 full cell showed an excellent Coulombic efficiency of 99.3% after 100 cycles. CH3NH3PBI3 (MAPbI3) perovskite solar cells (PSCs) were fabricated using a spin coating technique. A single PSC showed a power conversion efficiency of 12.95%. In order to develop a self-charging system for LIBs, four single PSCs connected in series were used as an LFP-LTO battery. The integrated PSC system showed a power conversion efficiency of 12.44%. The PSC-LIB coupled device showed excellent overall self-charging conversion and a storage efficiency of 9.25%.

Visible light (400-700 nm) lies outside of the spectral range of what photobiologists define as deleterious radiation and as a result few studies have studied the effects of visible light range of wavelengths on skin. This oversight is important considering that during outdoors activities skin is exposed to the full solar spectrum, including visible light, and to multiple exposures at different times and doses. Although the contribution of the UV component of sunlight to skin damage has been established, few studies have examined the effects of non-UV solar radiation on skin physiology in terms of inflammation, and limited information is available regarding the role of visible light on pigmentation. The purpose of this study was to determine the effect of visible light on the pro-pigmentation pathways and melanin formation in skin. Exposure to visible light in ex-vivo and clinical studies demonstrated an induction of pigmentation in skin by visible light. Results showed that a single exposure to visible light induced very little pigmentation whereas multiple exposures with visible light resulted in darker and sustained pigmentation. These findings have potential implications on the management of photo-aggravated pigmentary disorders, the proper use of sunscreens, and the treatment of depigmented lesions.

The social links between community entities are frequently regarded as a valuable asset for local economic development. Opinions diverge regarding the particulars of social capital and its constitution within social relations, despite its fundamental nature coming from these connections. Diverse public and private activities, according to Putnam (1995b), could constitute local social capital. While social capital can be conceptualized as private relations, assessing and debating it from the standpoint of local governments presents a formidable challenge. The distinction between the public and private spheres regarding the character of human activities was advanced by Arendt (1958). This study aims to frame the possible indicators for measuring local social capital by adopting Arendt's classical theory. By applying it to the social capital of the social communities, the research fills a gap in the discussion between public and private spheres. The integrated framework theoretically provides a backbone for the distinguished perspectives of social capital in different levels of human activities. As well as categorizing manageable and non-manageable indicators, it also provides practical policy implications for the criteria local governments place an emphasis on for managing the level of social capital in a region. It is anticipated that the framework will advance the expansion of the theoretical literature on social capital by identifying measures at two distinct levels: individual and collective characteristics. [ABSTRACT FROM AUTHOR]