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Finding a suitable material for hydrogen storage at ambient atmospheric conditions is challenging for material scientists and chemists. In this work, using a first principles based cluster expansion approach, the hydrogen storage capacity of Ti2AC (A = Al,Ti, Cr, Mn, Fe, Co, Ni, Cu, and Zn) MAX phase and its alloys were studied. We found that hydrogen is energetically stable in Ti-A layers in which the tetrahedral site consisting of one A atom and three Ti atoms is energetically more favorable for hydrogen adsorption than other sites in the Ti-A layer. Ti2CuC has the highest hydrogen adsorption energy than other Ti2AC phases. We find that 83.33% Cu doped Ti2AlxCu1-xC alloy structure is both energetically and dynamically stable and can store 3.66 wt% hydrogen at ambient atmospheric conditions, which is higher than both Ti2AlC and Ti2CuC phase. These findings indicate that the hydrogen capacity of the MAX phase can be significantly improved by doping an appropriate atom species.

Objectives: The aim of this study was to report a clinical case of decompensated liver cirrhosis in a patient with jaundice who showed improvement with Korean medicine treatment.Methods: A patient with decompensated liver cirrhosis with jaundice was treated with herbal medicine (Injinoryung-tang, Galgeunjowi-tang), acupuncture, cupping, and moxibustion. Changes in jaundice, fatigue, and dysuria were measured with subjective parameters. Liver function was checked by performing a blood test 8 times. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT), total bilirubin (TB), albumin, and platelets (Plt), prothrombin time (PT), and international normalized ratio (INR) were recorded.Results: The Korean medicine treatment improved jaundice, fatigue, and dysuria and lowered the AST, ALT, ALP, GGT, and TB levels.Conclusions: Korean medicine treatment containing Galgeunjowi-tang positively improves clinical symptoms and liver function.

Objectives: This study examined a clinical case of a recurrent polyarticular gout patient treated with Korean medicine.Methods: The patient was treated with Korean medicine (Gyejigagye-tang, Soshiho-tang-gami, Gyejigajakyak-tang, acupuncture, and moxibustion), Western medicine, and rehabilitative therapy. Their effects were evaluated using the Visual Analog Scale.Results: After receiving Korean medical treatment for two admission periods, the Visual Analog Scale score for joint pain improved or disappeared. Moreover, Korean medicine was able to manage the symptoms of the gout patient.Conclusions: Proper Korean medicine treatment could be effective in improving the symptoms of recurrent polyarticular gout pain.

The emission sources and their health risks of fine particulate matter (PM2.5) in Siheung, Republic of Korea, were investigated as a middle-sized industrial city. To identify the PM2.5 sources with error estimation, a positive matrix factorization model was conducted using daily mean speciated data from November 16, 2019, to October 2, 2020 (95 samples, 22 chemical species). As a result, 10 sources were identified: secondary nitrate (24.3%), secondary sulfate (18.8%), traffic (18.8%), combustion for heating (12.6%), biomass burning (11.8%), coal combustion (3.6%), heavy oil industry (1.8%), smelting industry (4.0%), sea salts (2.7%), and soil (1.7%). Based on the source apportionment results, health risks by inhalation of PM2.5 were assessed for each source using the concentration of toxic elements portioned. The estimated cumulative carcinogenic health risks from the coal combustion, heavy oil industry, and traffic sources exceeded the benchmark, 1E-06. Similarly, carcinogenic health risks from exposure to As and Cr exceeded 1E-05 and 1E-06, respectively, needing a risk reduction plan. The non-carcinogenic risk was smaller than the hazard index of one, implying low potential for adverse health effects. The probable locations of sources with relatively higher carcinogenic risks were tracked. In this study, health risk assessment was performed on the elements for which mass concentration and toxicity information were available; however, future research needs to reflect the toxicity of organic compounds, elemental carbon, and PM2.5 itself.

Fifteen airborne particulate matter-bound metals were analyzed at 14 sites in four large cities (Seoul, Incheon, Busan, Daegu) in South Korea, between August 2013 and June 2017. Among the seven sources resolved by positive matrix factorization, soil dust and marine aerosol accounted for the largest and second largest portions in the three cities; however, in Seoul, soil dust and traffic occupied the largest and the second largest, respectively. Non-carcinogenic risk assessed by inhalation of eight metals (Cd, Co, Ni, Pb, As, Al, Mn, and V) was greater than the hazard index (HI) of 1 at four sites located at or near the industrial complexes. Cumulative incremental lifetime cancer risk (ILCR) due to exposure to five metals (Cd, Co, Ni, Pb, and As) exceeded the 10−6 cancer benchmark at 14 sites and 10−5 at six sites, which includes four sites with HI greater than 1. The largest contributor to ILCR was coal combustion in Seoul, Incheon, and Daegu, and industry sources in Busan. Moreover, industry sources were the largest contributors to non-carcinogenic risk in Seoul, Busan, and Daegu, and soil dust was in Incheon. Incheon had the highest HI in spring because of the higher contribution of soil dust sources than in other seasons. The higher ILCR in Incheon in spring and winter and higher ILCR and HI in Daegu in autumn were mainly due to the influence of industry or coal combustion sources. Statistically significant differences in the ILCR and HI values among the sampling sites in Busan and Daegu resulted from the higher contribution of industry sources at a certain site in the respective city.

Phenacoccus solani Ferris, 1918 and Vryburgia distincta (De Lotto, 1964) are herein reported occurring on succulent plants (Echeveria spp.) in South Korea. Both species have not been documented from South Korea except for quarantine inspection reports. In this study, diagnoses, descriptions, and photographs of the two species are provided with general information about their host plants and distributions.

Objective: The purpose of this study was to investigate the effects of Korean medical treatment on a fibromyalgia patient with gastrointestinal symptoms, using herbal medicines selected according to new rather than existing standards.Method: A 52-year-old female patient with fibromyalgia was treated with Odu-tang and acupuncture, cupping, and moxibustion for 22 days. To evaluate the treatment, we used the Numerical Rating Scale (NRS), American College of Rheumatology’s Preliminary Diagnostic Criteria (ACR), and Korean Gastrointestinal Symptom Rating Scale (KGSRS).Result: Following treatment, pantalgia diminished, NRS, and ACR scores improved, and the GSRS score decreased from 29 to 11.Conclusion: This study suggests that Korean medical treatment could effectively reduce pain and improve digestive symptoms in patients with fibromyalgia. It also presents a new method that considers individual characteristics when choosing herbal medicine.

Compared with conventional liquid electrolytes, solid electrolytes can better improve the safety properties and achieve high-energy-density Li-ion batteries. Sulfide-based solid electrolytes have attracted significant attention owing to their high ionic conductivities, which are comparable to those of their liquid counterparts. Among them, Li thiophosphates, including Li-argyrodites, are widely studied. In this study, Li thiophosphate solid electrolytes containing BH

Solid-state inorganic magnesium batteries are considered as potential high energy storage devices of the future. Here we present a series of magnesium borohydride tetrahydrofuran (THF) composites, Mg(BH 4) 2 ⋅ xTHF(−MgO), 0≤x≤3, as solid-state electrolytes for magnesium batteries. Three new monoclinic compounds were identified, Mg(BH 4) 2 ⋅ 2/3THF (Cc), α-Mg(BH 4) 2 ⋅ 2THF (P2 1/c) and β-Mg(BH 4) 2 ⋅ 2THF (C2), and the detailed structures of α- and β-Mg(BH 4) 2 ⋅ 2THF are presented. The magnesium ionic conductivity of composites formed by these compounds were several orders of magnitude higher than that of the distinct compounds, x=0, 2/3, 2, and 3. The nanocomposite stabilized by MgO nanoparticles (∼50 nm), Mg(BH 4) 2 ⋅ 1.5THF−MgO(75 wt%), displayed the highest Mg 2+ conductivity, σ(Mg 2+)∼10 −4 S cm −1 at 70 °C, a high ionic transport number of t ion=0.99, and cyclic voltammetry revealed an oxidative stability of ∼1.2 V vs. Mg/Mg 2+. The electrolyte was stable towards magnesium electrodes, which allowed for stable Mg plating/stripping for at least 100 cycles at 55 °C with a current density of 0.1 mA cm −2. Finally, a proof-of-concept rechargeable solid-state magnesium battery was assembled with a magnesium metal anode and a TiS 2 cathode. A maximum discharge capacity of 94.2 mAh g −1 was displayed, which corresponds to y=0.2 in Mg yTiS 2.

This paper discusses the effect of AB2 (Ti(Cr, Fe)2) phase on the hydrogenation properties of a Ti–Fe–Cr alloy system. Five Ti–Fe–Cr based alloys were fabricated by varying the Cr content. The microstructural analysis results revealed that the fraction of the Ti(Cr, Fe)2 phase increased with the increasing Cr content. The first hydrogenation test results indicated that all the alloys could absorb a significant amount of hydrogen at room temperature (30 °C) without a separate activation process. This behavior improved when the Ti(Cr, Fe)2 phase existed in the AB phase; the kinetics of the first hydrogenation tended to increase with the fraction of Ti(Cr, Fe)2 phase. The enhancement in the first hydrogenation kinetics of the Ti–Fe–Cr based alloys was attributed to the synergetic effect of the interface between the AB and Ti(Cr, Fe)2 phases and the inherent fast hydrogenation of the Ti(Cr, Fe)2 phase. However, the total hydrogen storage capacity decreased when the fraction of Ti(Cr, Fe)2 phase increased.

Zirconium has been used as an alloying element to mitigate the difficulty in the initial hydrogenation of pristine TiFe, a room-temperature hydrogen storage material. The addition of zirconium induces the formation of AB2-type ternary phases such as τ1 and τ3. In this study, these ternary phases were produced individually and their activation kinetics and hydrogen storage properties were assessed. Ultimately, both τ1 and τ3 can be activated at room temperature under hydrogen at a pressure of 3 MPa. The result validates the presumption that Zr-added TiFe is easily activated with the help of the Ti–Fe–Zr ternary phases. In addition, they can store 1.8–1.9 wt% of hydrogen, which proves their own use as a hydrogen storage material. The easy activation may be caused by the compositional inhomogeneity of mixed metal oxide at the alloy surface, as revealed by depth-profiling X-ray photoelectron spectroscopy; this provides new reaction pathways for hydrogenation.

The black cut worm, Agrotis ipsilon (Hufnagel), is a destructive crop pest worldwide in tropical and subtropical regions, and a typical pest damaging plant parts below the soil surface, which requires thorough prediction of target stage for proper managing. This study was conducted to evaluate thermal effect on the development of A. ipsilon using Kimchi cabbage (Brassica campestris) as larval diet in a wide range of temperatures (10 to 40 ℃) in the laboratory. Temperature significantly affected the development time of eggs, larvae, and pupae of A. ipsilon. Using a linear model between temperature and development rate (1/days), lower threshold temperatures (LT) for eggs, larvae, and pupae were estimated to be 12.1 ℃, 9.6 ℃, and 11.2℃, respectively. Thermal constants (degree days, DD) for eggs, larvae, and pupae stages were 31.3 DD, 342.2 DD, and 181.3 DD, respectively. Thermal constant for each larval instar was also determined suing a common LT of 10.4 ℃: 40.3 DD for eggs, 315.6 DD for total larvae, and 199.6 DD for pupae. Stage transition models for all stages were constructed using two basic components of nonlinear development rate and distribution models to simulate the proportion of individuals shifted from one stage to the next stage. These models will be useful for constructing a population model for A. ipsilon in the future. Furthermore, the variation of development time of A. ipsilon reported in previous studies was discussed using 95% confidence limits of the estimated line of our nonlinear models.

Solid-state hydrogen storage covers a broad range of materials praised for their gravimetric, volumetric and kinetic properties, as well as for the safety they confer compared to gaseous or liquid hydrogen storage methods. Among them, AxBy intermetallics show outstanding performances, notably for stationary storage applications. Elemental substitution, whether on the A or B site of these alloys, allows the effective tailoring of key properties such as gravimetric density, equilibrium pressure, hysteresis and cyclic stability for instance. In this review, we present a brief overview of partial substitution in several AxBy alloys, from the long-established AB5 and AB2-types, to the recently attractive and extensively studied AB and AB3 alloys, including the largely documented solid-solution alloy systems. We not only present classical and pioneering investigations, but also report recent developments for each AxBy category. Special care is brought to the influence of composition engineering on desorption equilibrium pressure and hydrogen storage capacity. A simple overview of the AxBy operating conditions is provided, hence giving a sense of the range of possible applications, whether for low- or high-pressure systems.

This article reports the hydrogenation properties of several Mg–Mg2Ni composite specimens with increasing Ni content: 4.4, 11.3 (eutectic), and 16.3 (in at%). Mg–Mg2Ni composites were prepared by means of induction melting, followed by simple mechanical chipping of the casts. The hydrogenation and dehydrogenation reaction kinetics were studied, and reaction mechanisms were described by means of solid-gas reaction modeling. Absorption and desorption properties were evidenced to be diffusion controlled, with hydrogen diffusion through hydrided/dehydrided phases being the rate limiting step in most cases (the migration of metal/hydride interface at a constant velocity being rate-limiting in only few of them). The kinetics study was supported by a thorough thermal analysis to provide in-depth insights of the decomposition reaction. Hence, thermogravimetry (TG) and pressurized differential scanning calorimeter (PDSC) were combined to investigate the dehydrogenation properties such as hydrogen gravimetric density, reaction onset temperature, enthalpy and activation energy as a function of Ni content. Structural analysis included X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM, TEM) to discuss the structural stability and microstructural evolution as a function of cycles, notably during the activation procedure. Finally, cyclic performance was evaluated for 100 cycles, using a custom-made large-scale reactor to demonstrate scale-up feasibility.

Metal closo-borates have recently received significant attention due to their potential applications as solid-state ionic conductors. Here, the synthesis, crystal structures, and properties of (NH4)2B10H10·xNH3 (x = 1/2, 1 (α and β)) and (NH4)2B12H12·xNH3 (x = 1 and 2) are reported. In situ synchrotron radiation powder X-ray diffraction allows for the investigation of structural changes as a function of temperature. The structures contain the complex cation N2H7+, which is rarely observed in solid materials, but can be important for proton conductivity. The structures are optimized by density functional theory (DFT) calculations to validate the structural models and provide detailed information about the hydrogen positions. Furthermore, the hydrogen dynamics of the complex cation N2H7+ are studied by molecular dynamics simulations, which reveals several events of a proton transfer within the N2H7+ units. The thermal properties are investigated by thermogravimetry and differential scanning calorimetry coupled with mass spectrometry, revealing that NH3 is released stepwise, which results in the formation of (NH4)2BnHn (n = 10 and 12) during heating. The proton conductivity of (NH4)2B12H12·xNH3 (x = 1 and 2) determined by electrochemical impedance spectroscopy is low but orders of magnitude higher than that of pristine (NH4)2B12H12. The thermal stability of the complex cation N2H7+ is high, up to 170 °C, which may provide new possible applications of these proton-rich materials.

The spotted lanternfly (SLF), Lycorma delicatula (Hemiptera: Fulgoridae), has the potential to become a global pest and is currently expanding its range in the United States. In this study, we investigated the dispersal patterns of SLF in Ailanthus altissima during its oviposition period in South Korea using fluorescent marking system. Oviposition patterns of SLF were then analyzed by surveying egg masses in A. altissima patches. The recapture rate of fluorescent-marked SLF rapidly decreased < 30% within the first two weeks. During the oviposition period, seven cases of among-patch dispersal of SLF adults were observed with a minimum estimated dispersal distance mainly ranging between 10 - 60 m and a maximum of 1,740 m. Also, the number of A. altissima trees detected with fluorescent-marked SLF increased until late September. Based on the egg mass survey, a total of 159 egg masses were detected from 38 out of 247 A. altissima trees. Furthermore, ca. 80% of egg masses were located < 2.5 m above the ground. Finally, the number of egg masses showed significant positive correlations with the height and diameter at root collar of A. altissima trees; both tree height and DRC were significantly larger from the trees with egg masses.

Efficient storage of hydrogen is one of the biggest challenges towards a potential hydrogen economy. Hydrogen storage in liquid carriers is an attractive alternative to compression or liquefaction at low temperatures. Liquid carriers can be stored cost-effectively and transportation and distribution can be integrated into existing infrastructures. The development of efficient liquid carriers is part of the work of the International Energy Agency Task 40: Hydrogen-Based Energy Storage. Here, we report the state-of-the-art for ammonia and closed CO2-cycle methanol-based storage options as well for liquid organic hydrogen carriers.

The spotted lanternfly (SLF), Lycorma delicatula (Hemiptera: Fulgoridae), has the potential to become a global pest and is currently expanding its range in the United States. In this study, we investigated the dispersal patterns of SLF in Ailanthus altissima during its oviposition period in South Korea using a fluorescent marking system. Oviposition patterns of SLF were then analyzed by surveying egg masses in A. altissima patches. The recapture rate of fluorescent-marked SLF rapidly decreased to 30% within the first two weeks. During the oviposition period, seven cases of among-patch dispersal of SLF adults were observed. The minimum distance that SLF could have traveled to achieve these among-patch dispersal events ranged from 10 to 1740 m, with most events spanning under 60 m. Also, the number of A. altissima trees on which fluorescent marked SLF were detected increased until September. Based on the egg mass survey, a total of 159 egg masses were detected from 38 out of 247 A. altissima trees. Furthermore, 79.2% of egg masses were located A. altissima trees had significant effects on the number of egg masses.

Valorization of oil sludge has been gaining attention to improve the sustainability of the petroleum industry. This study aimed to assess the possibility of anaerobic co-digestion of oil scum and secondary sludge with food waste (or swine manure). Oil scum and secondary sludge were obtained from a wastewater treatment plant (WWTP) of a petrochemical plant. Physicochemical properties, hazardous materials, and microbial community were characterized and biochemical methane potential was performed by a simplex-lattice mixture design. More than 87% (wet wt.) of the oil scum consisted of total petroleum hydrocarbons (TPHs) (21,762 mg/L) that are difficult to be degraded by anaerobes. The secondary sludge showed low TPHs (5 mg/L) and a bacterial community similar to that of municipal WWTPs. The heavy metal (Cu, As, Cr, Ni, Mn, Zn, and V) concentrations in the oil scum and secondary sludge were similar (20-600 mg/L). The maximum methane potentials of the oil sludge and secondary sludges were 20 ± 2 and 56 ± 3 mL CH

The emission sources and their health risks of fine particulate matter (PM

Mechanochemical synthesis of CeB6 nanopowder was performed using a mixture of CeCl3, CeO2, B2O3 and either Mg or MgH2. The reaction for the CeO2-3B2O3-11MgH2 mixture to form CeB6 and MgO gradually proceeds during ball milling, while the mechanically induced self-propagating reaction (MSR) behavior is observed during ball milling of the CeO2-3B2O3-11 Mg mixture. X-ray diffraction patterns of the CeO2-3B2O3-11MgH2 mixture indicate that CeH2+x exists as an intermediate phase during the reaction. Scanning electron microscopy indicates that the particle size of CeB6 powder from the CeO2-3B2O3-11MgH2 mixture is much smaller than that from the CeO2-3B2O3-11 Mg mixture. Transmission electron microscopy revealed that CeB6 particles 10–30 nm in size from the CeO2-3B2O3-11MgH2 mixture are highly agglomerated with surface oxide layers. The mechanochemical reaction of the 2CeCl3-6B2O3-21MgH2 mixture produces CeB6 instead of Ce(BH4)3.

In the aim of evidencing the relationship between Mg2FeH6 synthesis and the size of Fe particles, several specimens have been prepared by applying various milling energies (milling time) on a 2.1 Mg and 1Fe powder mixture doped with a small fraction of Unsaturated Fatty Amine (UFA). The resulting nano-crystalline composite structures display a broad Fe particle size distribution as a function of milling time. The hydrogenation of those complex powders has been conducted at temperatures lower than 400 °C under 60 bar of hydrogen pressure. As expected, the Fe particle size significantly influenced the hydrogenation kinetics. Also, the inevitable distribution of a minor fraction of oxides occurring during the milling process affected greatly the hydrogen storage capacity. Under the low pressure and temperature conditions selected in the frame of this study, lower than 100 bar and 500 °C conventionally used for synthesis of high purity Mg2FeH6, the hydrogenation reaction was demonstrated to be almost completed within 6 h, confirming the fast hydrogen absorption capability of the prepared materials. Plus, nearly 84 wt% of Mg2FeH6 was achieved under the afore mentioned moderate conditions and a minor fraction of unreacted Fe still remained due to diffusion constraints existing at low temperatures.

Metcalfa pruinosa (Say) has rapidly established and spread through Korea since its first reported occurrence in 2009, causing serious economic damage to various agricultural crops. Several statistical modeling methods and MaxEnt software were used with spatio-temporal occurrence information in Korea, in order to verify fast expansion triggered by human-mediated factor, and predict potential distribution and its determinants of M. pruinosa for efficient management. Results showed that the estimated spread rate and pattern of M. pruinosa in Korea were significantly different from a continuous spreading pattern. In early spread phase in 2013, traffic volume, one of human mediated factors, was the most important environmental factor. Traffic volume of the relative pre-occupied habitat in 2013 was also significantly (P

The time-lag method is a technique to derive the permeability of a membrane from the time-variant outflux of a permeate. The original formulation assumes an invariant outlet pressure; however, for practical reasons, the permeate is often contained in a finite outlet volume, and the outflux is evaluated using the increase in the outlet pressure. The outlet pressure change inevitably introduces an error in the diffusivity and in the solubility, i.e., Sieverts' constant. We demonstrate that when a time lag is obtained from the tangent line at the maximum flux, the error in the diffusivity stays within ca. 2% under usual experimental conditions. On the other hand, Sieverts' constant is underestimated to a larger degree if the outlet pressure change is not considered. To solve this problem, we propose a finite outlet volume correction to the time-lag method for the case of hydrogen permeation. The proposed scheme is an approximate solution that is valid when a linear hydrogen concentration profile is developed across the membrane. When the correction method is applied to characterize V-alloy and Pd membranes, the simulated outlet pressure from the corrected Sieverts’ constant closely approximates the experimental data. The proposed method does not require any additional measurements and greatly improves the accuracy of the permeability measurement.