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In this study , short -circuit processes were analyzed via simulations and experiments by applying a principle that can interpret the short-circuit marks, which are the most basic inspection criteria in fire-scene investigation. According to Fleming's left-hand rule, a Lorentz force is generated when current and magnetic fields are applied. Railgun, one of the typical applications, utilizes the same basic principle for generating trajectories. Using the same concept, it was interpreted that the molten copper balls generated during a short-circuit process scatter in the load direction similar to a ballistic launch. The simulation and experimental results also confirmed that the copper balls were scattered in the load direction owing to the Lorentz force. Although it is impossible to examine the source and load during a fire-scene investigation process, the study findings will aid in predicting the load by observing the portion where the copper bulbs are relatively frequent. Thus, based on an estimation of the cause of fire, it will be possible to infer reliable results through fire-scene investigation.

Ammonia can be applied as a hydrogen carrier and used directly as a hydrogen production supply. In this paper, a technique for mass-producing hydrogen from ammonia water is proposed by applying a liquid phase plasma (LPP) discharge technique and a photocatalyst. In this reaction, N- and Fe ion codoped TiO2 (N/Fe/TiO2) photocatalysts were prepared and applied as a visible light-sensitive photocatalyst. N/Fe/TiO2 (NFT) had a similar crystal shape and size to anatase TiO2, but the surface was doped with metal ions. The bandgap of the NFT photocatalyst obtained from the spectrum measured by photoluminescence spectroscopy was approximately 2.4 eV. Nitrogen and Fe ions played a role in narrowing the gap between the conduction band (CB) and valence band (VB) of TiO2, effectively reducing the bandgap. In the decomposition reaction of ammonia water by LPP irradiation, the NFT photocatalyst showed the highest hydrogen evolution rate. The amount of hydrogen produced from ammonia water by LPP irradiation on the NFT photocatalyst was approximately 133 L/h. The hydrogen production rate obtained from ammonia water by the photocatalyst and LPP irradiation was significantly higher than that obtained by the ammonia electrolysis process.

Improving solar energy conversion efficiency and reducing energy loss have become critical issues in recent decades. Photoelectrochemical (PEC) water splitting provides an ideal method for solar energy harvesting and is a key factor in decreasing the use of fossil fuels. Thus, it is extremely important to identify cost-effective, highly active, and robust semiconducting photoelectrodes that can reduce the overpotential reaction and increase electrocatalytic efficiency. However, for overall water splitting, it is challenging to identify suitable photocatalysts with efficient band structures and suitable charge separation for electron-hole pairs. Water splitting is conventionally performed using independent layer-by-layer (LBL) or hydrothermal (HT) techniques. However, this research aims to produce a photoanode by applying both HT and LBL methods in sequence to reduce energy loss during the electron transfer process between the two photosystems. In this study, a TiO2 layer was deposited onto fluorine tin oxide (FTO) glass using the LBL method (TiO2/FTO). Subsequently, hematite (alpha-Fe2O3) thin films that were synthesized using the HT method were deposited onto TiO2/FTO glasses (Fe2O3/TiO2/FTO). The as-prepared and newly-designed photoanode Fe2O3/TiO2/FTO demonstrates a significantly high photocatalytic activity of 7.68 mA/cm(2). Thus, by combining the HT and LBL methods, excellent hydrogen production performance in regard to photocatalytic water splitting was achieved. Furthermore, this hierarchical structure provides good chemical stability and is an excellent candidate for large-scale applications. Refereed/Peer-reviewed

In this paper, fire caused by low-temperature ignition of wood was analyzed. The hourly change in wood characteristics caused by the radiant heat of a sheath heater was also studied. A sheath heater with a maximum heat output of 6 kW was installed in a cedar sauna room with dimensions of 120(W) × 100(D) × 185(H) cm3. Changes in the wood surface were monitored while decreasing the distance between the wood wall and the sheath heater from 10 to 5 cm. At a distance of 10 cm, the wood surface started to become discolored from amber to dark brown after approximately 32 h. At a distance of 5 cm, after approximately 56 h, the surface began to crack while being carbonized. At this time, the average temperature of the wood surface was ~120 °C. After 88 h, the temperature reached 644 °C and a fire started, generating white smoke. This study is important to the field of fire investigation owing to a lack of prior studies concerning the changes in the surface characteristics of wood upon sustained exposure to radiant heat.

In this study, europium (Eu) was precipitated in TiO2 powder using liquid phase plasma (LPP) process to prepare a photocatalyst with higher activity, even in the visible light range. Eu was uniformly deposited on the surface of TiO2 by the LPP method. It was observed that the amount of Eu precipitated on the TiO2 surface increased with increasing precursor concentration. XPS and EDS analysis showed that Eu was precipitated as europium oxide. The precipitation of Eu shifted the position of the Raman peak to a higher wavelength; with higher Eu content, the band gap energy decreased. Particularly, the photocatalytic efficiency of the Eu doped TiO2 photocatalyst (EDTP) in the visible light source was much higher than that of bare TiO2, and with higher Eu content, the photocatalytic activity was improved. Acetylsalicylic acid was attacked by HO∙ produced on the EDTP’s surface and assumed to be finally mineralized to H2O and CO2 via two decomposition pathways, namely, decarboxylation and deacetylation.

Few studies have considered using artificial neural networks to predict the temperature distribution inside a room with a heat source, even though such an approach is potentially much faster than numerical analysis. In this study, a multilayer perceptron (MLP) model was developed and applied to predicting the temperature distribution in a room with a heat source, where the input variables were the x- and y-coordinates and the distances from the bottom of the wall to the airflow inlet and outlet. The MLP model was trained and evaluated to optimize the hyperparameters (i.e., batch size, node, learning rate, and number of layers) for the prediction accuracy. When compared with a computational fluid dynamics (CFD) simulation, the MLP model showed comparable prediction accuracy, but the computational time was about 11 s compared with 27 min for the CFD simulation. Thus, the MLP model can predict the temperature distribution in a room with an internal heat source with high accuracy and very low computational cost.

Herein, we report a simple and scalable synthesis route to prepare Ag-functionalized porous ZnO sheets and their enhanced NO2 gas sensing properties. Porous ZnO sheets functionalized with well-dispersed submicron Ag particles were prepared by using a hydrothermal method-based one-pot synthesis route from Zn and Ag precursors. NO2 gas sensing performance (response, selectivity, response time, and recovery time) was optimized at 200°C in the gas sensor fabricated with 3 at% Ag-functionalized porous ZnO sheets. We demonstrated a response ( R g / R a ) of 17.18 to 10 ppm NO2 gas and also obtained a high response of 14.05 even at 60% relative humidity due to the synergetic effect of improved NO2 gas adsorption in the presence of Ag particles and increased resistance by the formation of Schottky barrier at Ag-ZnO heterojunctions.

Radiation causes damage to the human body, the environment, and electronic equipment. Shielding against neutron and gamma rays is particularly difficult because of their strong ability to penetrate materials. Conventional gamma ray shields are typically made of materials containing Pb. However, they pose problems in that Pb is a heavy metal, and human poisoning and/or pollution can result from the manufacturing, use, and disposal of these materials. In addition, neutron rays are shielded by materials rich in H2 or concrete. In the case of the latter, the manufacturing cost is high. Thus, it is necessary to develop a new multilayer structure that can shield against both neutron and gamma rays. We set up a simulation model of a multilayered structure consisting of metal hydrides and heavy metals, and then evaluated the simulations using Monte Carlo N-Particle Transport Code. Monte Carlo simulation is an accurate method for simulating the interaction between radiation and materials, and can be applied to the transport of radiation particles to predict values such as flux, energy spectrum, and energy deposition. The results of the study indicated the multilayer structure of ZrH2, U, and W could shield both neutron and gamma rays, thus showing potential as a new shielding material to replace Pb and concrete.

The construction of carbon-coated heterostructures of bimetallic sulfide is an effective technique to improve the electrochemical activity of anode materials in lithium-ion batteries. In this work, the carbon-coated heterostructured ZnS-FeS2 is prepared by a two-step hydrothermal method. The crystallinity and nature of carbon-coating are confirmed by the investigation of XRD and Raman spectroscopy techniques. The nanoparticle morphology of ZnS and plate-like morphology of FeS2 is established by TEM images. The chemical composition of heterostructure ZnS-FeS2@C is discovered by an XPS study. The CV results have disclosed the charge storage mechanism, which depends on the capacitive and diffusion process. The BET surface area (37.95 m2g−1) and lower Rct value (137 Ω) of ZnS-FeS2@C are beneficial to attain higher lithium-ion storage performance. It delivered a discharge capacity of 821 mAh g−1 in the 500th continuous cycle @ A g−1, with a coulombic efficiency of around 100%, which is higher than the ZnS-FeS2 heterostructure (512 mAh g−1). The proposed strategy can improve the electrochemical performance and stability of lithium-ion batteries, and can be helpful in finding highly effective anode materials for energy storage devices.

Prenatal exposure to valproic acid (VPA) has been implicated in the manifestation of autism spectrum disorder (ASD)-like behavioral and functional changes both in human and rodents including mice and rats. The objective of this study was to determine metabolomics profiling and biomarkers related to VPA-induced symptoms resembling ASD using proton nuclear magnetic resonance (1H-NMR) spectral data. VPA was administered to pregnant rats at gestation day 12.5 and effects measured subsequently in male 4-week-old offspring pups. The sociability of VPA-treated animals was significantly diminished and exhibited ASD-like behavior as evidenced by reduction of social adaptation disorder and lack of social interactions. To find biomarkers related to ASD, the following were collected prefrontal brain cortices, urine bladder and blood samples directly from heart puncture. In all samples, principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) displayed significant clustering pattern differences between control and treated groups. Valine, taurine, myo-inositol, 3-hydroxybutyrate and 1,3-dihydroxyacetone were significantly decreased in brain cortices in treated rats. Serum metabolites of glucose, creatine phosphate, lactate, glutamine and threonine were significantly increased in VPA-administered animals. Urinary metabolites of pimelate, 3-hydroxyisovalerate and valerate were significantly reduced in VPA-treated rat, whereas galactose and galactonate levels were elevated. Various metabolites were associated with mitochondrial dysfunction metabolism and central nervous system disorders. Data demonstrated that VPA-induced alterations in endogenous metabolites of serum, urine, and brain cortex which might prove useful as biomarkers for symptoms resembling ASD as a model of this disorder.

The present study demonstrates the thermal stability and photocatalytic activity of TiO2-based nanotubes with respect to post-hydrothermal treatment. Titanate nanotubes were synthesized by adapting an alkali hydrothermal method from TiO2 sol using NaOH as a catalyst. The effect of post-hydrothermal heating on the properties—such as structure, morphology, textural properties, and activity—of as-synthesized one-dimensional titania nanostructure is investigated in detail. The characterizations are carried out using SEM, EDX, TEM, XRD, and a BET surface area analyzer. When heated in the presence of water in an autoclave, the protonated titanate phase of the nanotubes converts to anatase phase. Meanwhile, the tubular morphology is gradually lost as the post-hydrothermal heating duration increases. The photocatalytic activity was assessed utilizing the photo-oxidation of an amaranth dye. It is discerned that the as-prepared nanotubes are photocatalytically inactive but become active after post-hydrothermal processing. The activity trend follows the formation of the active phase—the titanate phase crystallizes into a photocatalytically-active anatase phase during post-hydrothermal heating. The effect of experimental parameters, such as reaction pH, dye concentration, and amount of catalyst, on the dye removal is studied. The findings also highlight that the role of holes/OH• is more prominent as compared to conduction band electron/O2−• for the removal of the dye. In addition, the photocatalyst exhibited excellent stability and reusability.

Energy is a key factor in determining the growth of human society [...]

This study developed a new water treatment method using liquid-phase plasma (LPP) process that can decompose oxytetracycline (OTC) remaining in the aquatic environment. Relatedly, the OTC causes damage to the human body and cannot be removed by traditional water treatment methods. The study also prepared Fe/TiO

The most pressing concerns in environmental remediation are the design and development of catalysts with benign, low-cost, and efficient photocatalytic activity. The present study effectively generated a flower-like indium oxide (In

The degradation of chloroform in a liquid phase plasma (LPP) reactor was examined according to the operating parameters and other influencing factors. The operating parameters included the applied voltage, frequency, and pulse width. The effects of titanium dioxide, hydrogen peroxide, and their combination on the degradation of chloroform were evaluated in terms of the influencing factors. Increasing the operating parameters up to the maximum allowed in the LPP process made chloroform decompose much faster than that of the minimum. On the other hand, increasing either the titanium dioxide or hydrogen peroxide concentrations in the reactant solution did not always destroy the chloroform efficiently compared to degradation without their loading. Although the impact of titanium dioxide was slightly higher than that of hydrogen peroxide, the synergistic effect between them enhanced the breakdown of chloroform further. Overall, both the operating parameters and influencing factors should be determined carefully to maximize the decomposition efficiency in the given treatment system, particularly for processes involving the LPP reaction.

Understanding the performance and mechanism of the degradation of various contaminants is essential for the effective design of wastewater treatment systems. This study examined the degradation of 1,4-dichlorobenzene in a photocatalytic system, which embedded TiO2 particles (as a thin film) on alumina balls (as a solid support). Decomposition of the parent compound was assessed by introducing a TiO2 photocatalyst, microwave irradiation, and ultraviolet irradiation jointly or separately (in terms of the system configuration) with and without an adjustment for the microwave intensity, pH, and hydrogen peroxide levels (in terms of the operating conditions) to the photocatalytic system. The results showed that the photocatalytic system adopting multiple processes concomitantly improved the degradation performance of the parent compound that was resistant to the single-unit processes. On the other hand, the decomposition efficiency was increased further with the sophisticated control of the operating conditions, specifically the pH and hydrogen peroxide levels. A dechlorination process as well as substitution and addition reactions involving the hydroxyl radical appeared to occur in the degradation pathway to produce four degradation products from the parent compound. The significance of this study lies in the introduction of a systematic approach to optimizing the operating conditions that facilitate the decomposition efficiency in a given photocatalytic system at no extra cost.

Photocatalysts responding to visible light were prepared by doping ytterbium (Yb) to TiO2 powder by LPP method. Yb2O3 nanoparticles were uniformly precipitated on the surface of TiO2 powder, and when the precursor concentration was increased, the precipitated Yb2O3 nanoparticles increased. The precipitated Yb element lowered the band gap energy of Yb-doped TiO2 photocatalyst (YTP) by 0.07 to 0.14 eV compared to bare TiO2. YTPs degraded naproxen (NPX) better than bare TiO2, especially under blue LED light (maximum wavelength 470 nm), and YTP containing higher Yb elements showed higher decomposition activity. NPX was decomposed into CO2 and H2O by decarboxylation and demethylation by hydroxyl radicals generated from TiO2 photocatalysts, suggesting a degradation pathway based on the three intermediates detected by LC/MS analysis.

SiOx is investigated as a promising anode material for lithium-ion batteries (LIBs) for replacing Si, which undergoes huge volume changes during lithiation/delithiation, even though its energy dens...

In Korea, sudden cold weather in spring occurs repeatedly every year and causes severe damage to field crops and fruit trees. Detailed forecasting of the daily minimum or suddenly decreasing temperature, closely related to the local topography, has been required in the farmer community. High-resolution temperature models based on empirical formulas or statistical downscaling have fundamental limitations, making it difficult to perform biophysical application and mechanism explanation on small-scale complex terrains. Weather Research and Forecasting–Large Eddy Simulation (WRF–LES) can provide a dynamically and physically scientific tool to be easily applied for farm-scale numerical weather predictions. However, it has been applied mainly for urban areas and in convective boundary layer studies until now. In this study, 20 m resolution WRF–LES simulation of nighttime near-surface temperature and wind was performed for two cold spring weather events that induced significant crop damages in the apple production area and the results were verified with automatic weather station observation data. The study showed that the maximum mean bias of temperature was −1.75 °C and the minimum was −0.68 °C in the spring, while the root mean square error varied between 2.13 and 3.00 °C. The minimum temperature and its duration significantly affected the crop damage, and the WRF–LES could accurately simulate both features. This implies that the application of WRF–LES, with proper nest-domain configuration and harmonized physical options, to the prediction of nighttime frost in rural areas has promising feasibility for orchard- or farm-scale frost prevention and low-temperature management.

CoW using TSV technology has been suggested for process flexibility with high bandwidth in wafer level process (WLP). To connect I/O terminals, Thermo-compression process is generally used with using of non-conductive film (NCF). Although TC-NCF can suppress inner void and have a high production efficiency, solder sweep phenomenon, one of device fail reasons between signal bumps, was reported. This paper focus on design for three dimensional packaging technology and discuss optimal bonding process, NCF material and bump array design. TC-bonding simulation is also adapted for increasing experimental accuracy. The simulation is successfully estimated a sweep behavior and well matched with actual experimental results. It is expected that I/O counts per unit area is be expected to increase about 4 times and flexibility of I/O layout was also ensured.

In November 2013, a case of sustained combustion of a female body was encountered in a Korean farming village. The body was almost completely incinerated from the neck to the knees, and other parts of the body, such as the head, arms, lower legs, and feet, were slightly damaged. The most likely external ignition source was the flame from a matchstick. The elderly woman was found incinerated on the floor of the living room, while other objects in the house were largely undamaged except for having a brown oily or greasy coating. Flammable substances were not detected from the woman’s intact pieces of clothing and socks, and her muscular tissues did not contain toxic chemicals. The concentration of carboxyhemoglobin in her peripheral blood was 11% and that of ethyl alcohol in her aqueous humor was below 0.010%. An autopsy failed to determine the exact cause of death because of excessive charring.

Ethanolamine in a wastewater which is released from nuclear power plant was decomposed using a plasma discharged into the solution directly. Ni-TiO2 supported on mesoporous materials were employed as a photocatalyst. The photocatalytic reaction using the liquid phase plasma led to a degradation of ethanolamine with hydrogen evolution, simultaneously. The ethanolamine in the wastewater was degraded over 90% on the photocatalytic decomposition reaction by irradiation of liquid phase plasma. The rate of hydrogen evolution increased significantly with Ni incorporation on TiO2 because the bandgap was reduced with Ni incorporation on TiO2. Incorporating Ni on TiO2 nanocrystallites brought out an improvement of the ethanolamine degradation with hydrogen generation. The rate of hydrogen evolution in the ethanolamine-containing aqueous solution was increased in comparison with that in pure water. Additional hydrogen evolution by the photodecomposition of ethanolamine was attributed to the increasing H2 production.

Effects of tensile strain induced by the dispersion of Au nanoparticles in Pr2NiO4-based oxide on the oxygen reduction reaction were investigated. Au-dispersed Pr1.9Ni0.71Cu0.41Ga0.05O4+δ (PNCG) showed a much decreased cathodic overpotential, and a cell using Au-dispersed PNCG showed a significantly higher power density, approximately 2.5 times higher than that of a cell using PNCG without dispersed Au. The smallest overpotential was achieved at 3–5 mol % dispersion of Au nanoparticles, at which the largest tensile strain was observed. Impedance measurements suggested that the impedance arc in the lower frequency range was mainly decreased; therefore, the increased activity to oxygen reduction was attributed to the increased bulk and surface diffusivity of oxide ions. Electron energy loss spectroscopy (EELS) shows that oxygen in the strained region was in a more reduced state and this oxygen could be assigned to interstitial oxygen which is highly mobile. In addition, density functional theory (DFT) analy...

The diagnosis of encapsulated follicular-patterned thyroid carcinoma (EFPTC) is challenging, and the detection of capsular invasion and/or vascular invasion is essential in distinguishing benign lesions from malignant lesions. In this study, we present a modified transverse-vertical gross examination method with additional vertical cuts at the upper and lower ends of thyroid nodules. In addition, we compared the clinicopathological characteristics of patients with EFPTC between conventional and modified methods. The diagnostic rate of follicular thyroid carcinoma and invasive encapsulated follicular variant of papillary thyroid carcinoma was higher with the modified method (p = 0.003 and p = 0.028, respectively). Furthermore, the paraffin block number and the number of capsular invasion per centimeter were significantly higher with the modified method (p