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Highly efficient CO and syngas production in a cyclic system was proposed using coke-promoted Ni/CaO (C-Ni/CaO) catal-sorbent. The C-Ni/CaO exhibited high CO production in CO2 conversion and syngas production in CH4 conversion step, respectively.

A series arc produces both light and heat, which results in a risk of fire. Hence, its prompt detection is very important. The series arc has different frequency characteristics depending on the operating conditions of the inverter and the line impedance. As a result, it is difficult to detect with conventional methods that use specific frequency bands. In this study, series arcs generated by three-phase pulse-width-modulated and three-phase model-predictive-control inverter loads, operating under various conditions, were detected using a deep-learning algorithm. To detect a series arc fault, the frequency characteristics were analyzed using all the frequency bands of a fast Fourier transform (FFT) result. To use all the frequency bands, a deep neural network (DNN), which is a deep-learning algorithm, was used. DNNs can learn quickly from large amounts of data and model complex nonlinear relationships. The DNN model proposed in this paper was designed to use all the frequency bands, and three cases were tested by changing the current magnitude and switching frequency. The arc current detection accuracy was calculated for three test cases and the obtained results were analyzed in detail based on the percentages of true/false and mean absolute error metrics. The analysis confirmed that the arc current was accurately detected, which validates the suitability of the DNN for series arc detection.

The Rare Isotope Science Project was launched in 2011 in Korea toward constructing the Rare isotope Accelerator complex for ON line experiments (RAON). RAON will house several experimental systems, including the Muon Spin Rotation/Relaxation/Resonance (μSR) facility in High Energy Experimental Building B. This facility will use 600-MeV protons with a maximum current of 660 pμA and beam power of 400 kW. The key μSR features will facilitate projects related to condensed-matter and nuclear physics. Typical experiments require a few million surface muons fully spin-polarized opposite to their momentum for application to small samples. Here, we describe the design of a muon transport beam line for delivering the requisite muon numbers and the electromagnetic-component specifications in the μSR facility. We determine the beam-line configuration via beam-optics calculations and the transmission efficiency via single-particle tracking simulations. The electromagnet properties, including fringe field effects, are applied for each component in the calculations. The designed surface-muon beamline is 17.3 m long, consisting of 2 solenoids, 2 dipoles affording 70° deflection, 9 quadrupoles, and a Wien filter to eliminate contaminant positrons. The average incident-muon flux and spin rotation angle are estimated as 5.2 × 106 μ+/s and 45°, respectively.

Following the launch of Rare Isotope Science Project in December 2011, a heavy ion accelerator complex in South Korea, named RAON, has since been designed. It includes a muon facility for muon spin rotation, relaxation, and resonance. The facility will be provided with 600 MeV and 100 kW (one-fourth of the maximum power) proton beam. In this study, the graphite target in RAON was designed to have a rotating disk shape and was cooled by radiative heat transfer. This cool-down process has the following advantages: a low-temperature gradient in the target and the absence of a liquid coolant cooling system. Monte Carlo simulations and ANSYS calculations were performed to optimize the target system in a thermally stable condition when the 100 kW proton beam collided with the target. A comparison between the simulation and experimental data was also included in the design process to obtain reliable results. The final design of the target system will be completed within 2020, and its manufacturing is in progress. The manufactured target system will be installed at the RAON in the Sindong area near Daejeon-city in 2021 to carry out verification experiments.

June Yong Park,1,* Yuseon Shin,1,* Woong Roeck Won,1 Chaemin Lim,1,2 Jae Chang Kim,1 Kioh Kang,1 Patihul Husni,1 Eun Seong Lee,3 Yu Seok Youn,4 Kyung Taek Oh1,5 1Department of Global Innovative Drugs, The Graduate School of Chung-Ang University, Dongjak-gu, Seoul, 06974, Republic of Korea; 2Center for Nanotechnology in Drug Delivery and Division of Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA; 3Division of Biotechnology, The Catholic University of Korea, Bucheon, Gyeonggi-do, 14662, Republic of Korea; 4School of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do, 16419, Republic of Korea; 5College of Pharmacy, Chung-Ang University, Dongjak-gu, Seoul, 06974, Republic of Korea*These authors contributed equally to this workCorrespondence: Kyung Taek OhCollege of Pharmacy, Chung-Ang University, 221 Heukseok-dong, Dongjak-gu, Seoul, 06974, Republic of KoreaTel +82-2-824-5617Email kyungoh@cau.ac.krPurpose: An AE147 peptide-conjugated nanocarrier based on PEGylated liposomes was developed in order to target the metastatic tumors overexpressing urokinase-type plasminogen activator receptor (uPAR), which cancer progression via uPA signaling. Therefore, the AE147 peptide-conjugated nanocarrier system may hold the potential for active targeting of metastatic tumors.Methods: The AE147 peptide, an antagonist of uPAR, was conjugated to the PEGylated liposomes for targeting metastatic tumors overexpressing uPAR. Docetaxel (DTX), an anticancer drug, was incorporated into the nanocarriers. The structure of the AE147-conjugated nanocarrier, its physicochemical properties, and in vivo biodistribution were evaluated.Results: The DTX-loaded nanocarrier showed a spherical structure, a high drug-loading capacity, and a high colloidal stability. Drug carrying AE147 conjugates were actively taken up by the uPAR-overexpressing MDA-MB-231 cancer cells. In vivo animal imaging confirmed that the AE147-conjugated nanoparticles effectively accumulated at the sites of tumor metastasis.Conclusion: The AE147-nanocarrier showed potential for targeting metastatic tumor cells overexpressing uPAR and as a nanomedicine platform for theragnosis applications. These results suggest that this novel nano-platform will facilitate further advancements in cancer therapy.Keywords: tumor-targeting ligand, urokinase-type plasminogen activator, liposome, circulating tumor cell, metastatic tumor

Amine-functionalized silica sorbents have been widely investigated for post-combustion CO2 capture at low temperature. In previous studies, amine-functionalized silica sorbents were prepared using a synthetic hierarchically porous silica, which is not commercially available in large quantities, because porous silica support structures strongly influence CO2 capture performance. Here, we propose a feasible and facile fabrication method for amine-functionalized silica sorbents using 3-aminopropyltrimethoxy silane (APTS) and fumed silica (FS), where APTS serves as both an active material and a binder. The APTS-functionalized FS sorbents have large amounts of active amino groups and porous structures and demonstrate good multicycle stability with excellent CO2 capture performance. In addition, cetyltrimethylammonium bromide was found to improve the diffusion pathway of CO2, leading to enhanced CO2 capture capacity because of the suppression of excessive condensation during preparation. Therefore, the APTS-functionalized FS sorbents could be cost- and energy-efficiently prepared using a novel one-pot synthesis method; the resulting sorbents exhibit excellent CO2 capture performance.

SnO2 thin-film gas sensors were easily created using the ion sputtering technique. The as-deposited SnO2 thin films consist of a tetragonal SnO2 phase and densely packed nanosized grains with diameters of approximately 20−80 nm, which are separated by microcracks. The as-deposited SnO2 thin film is well crystallized, with a dense columnar nanostructure grown directly onto the alumina material and the Pt electrodes. The grain size and thickness of SnO2 thin films are easily controlled by varying the sputtering time of the ion coater. The responses of the SnO2 thin-film sensors decrease as the SnO2 film thickness is increased, indicating that a negative association exists between the sensor response and the SnO2 film thickness due to gas diffusion from the surface. The SnO2 thin-film sensor, which was created by ion sputtering for 10 min, shows an excellent sensor response (Ra/Rg where Ra is the electric resistance under air and Rg is the electric resistance under the test gas) for detecting 1 ppm H2S at 350°C.

Co-based catalysts were developed for the production of high-calorie synthetic natural gas. The Co reduction in Al2O3- and SiO2-supported catalysts prepared with different Co loading, and their catalytic properties for high-calorie methanation were investigated. The CO conversion of the Co/SiO2 catalysts was superior to that of the Co/ Al2O3 with the same Co loading, due to their better reducibility at 400°C. The activities of both the Al2O3 and SiO2-supported catalysts increased with Co loading, while the growth of hydrocarbon chains decreased as the Co loading increased. As the reduction temperature increased, crystallite size of Co increased in 10Co/SiO2, resulting in decrease of CO conversion and increase of C2+ selectivity. The highest CO conversion (98.7%) was obtained over 10Co/SiO2 reduced at 400 °C. Moreover, the heating value of the product gas (10,405 kcal/Nm3) exceeded the standard heating value without requiring a high reduction temperature (700 °C) or a noble metal (Ru).

A novel integrated CO2 capture and utilization (CCU) process for direct methanation was proposed to reduce the total required thermal energy by effectively combining CO2 capture and conversion using a Ni/CaO catal-sorbent. Compared to the conventional carbonation/decarbonation process, carbonated Ni/CaO catal-sorbents were regenerated by converting captured CO2 to CH4 under a H2 atmosphere at temperatures lower than those required for CO2 desorption. According to the theoretical and experimental results, the optimum reaction temperature for the novel CCU process was determined at 500 °C; while the Ni/CaO catal-sorbent exhibited high CO2 capture and direct methanation capacity without sintering during consecutive cycle tests at 500 °C. Therefore, this new integrated CCU process for direct methanation could be a cost- and energy-effective approach to CH4 production and climate emergency mitigation.

Over the past few decades, hyperthermia therapy (HTT) has become one of the most promising strategies to treat cancer. HTT has been applied with nanotechnology to overcome drawbacks such as non-selectivity and invasiveness and to maximize therapeutic efficacy. The high temperature of HTT induces protein denaturation that leads to apoptosis or necrosis. It can also enhance the effects of other cancer therapies because heat-damaged tissues reduce radioresistance and help accumulate anticancer drugs. Gold nanoparticles and superparamagnetic iron oxide with different energy sources are commonly used as hyperthermia agents. New types of nanoparticles such as those whose surface is coated with several polymers and those modified with targeting moieties have been studied as novel HTT agents. In this review, we introduce principles and applications of nanotechnology-based HTT using gold nanoparticles and superparamagnetic iron oxide.

CO2 green technologies, such as methanation, reverse water-gas shift (rWGS), and dry reforming of methane (DRM), in CO2 capture and direct utilization processes are proposed to reduce the total thermal energy by effectively combining CO2 capture and conversion using Ni/CaO catal-sorbents. Compared to conventional calcium looping using CaO-based sorbents, carbonated Ni/CaO catal-sorbents are completely regenerated at lower temperatures by simultaneously converting the captured CO2 into chemicals via methanation, rWGS, or DRM. At optimum temperatures and concentrations of the feed gas (H2 or CH4), the Ni/CaO catal-sorbents show excellent CO2 capture capacity and productivity. In addition, the structural variation of the Ni/CaO catal-sorbents is elucidated. Based on these theoretical and experimental studies, the novel integrated CO2 capture and direct utilization processes can be a promising technology to produce chemicals as well as mitigate CO2 levels from large-scale sources.

Recently, lithium-ion batteries have become widespread as a source of power or energy for everything from portable electronics to electric vehicles. As a result, the consumption of lithium is rapidly increasing, accompanied by an increase in its price. This study reports the synthesis of a regenerable sodium-based lithium silicate solid sorbent that uses less lithium than Li4SiO4 solid sorbents. The regenerable sodium-based lithium silicate solid sorbent was prepared by mixing LiOH with a sodium silicate solution in a 2:1 M ratio, which steadily maintained its CO2 capture capacity during multiple cycles. In addition to Li4SiO4 present in the developed solid sorbent, we attribute CO2 sorption and regeneration to a new structure, namely Li3NaSiO4. Notably, the LONS2 solid sorbent exhibits a faster CO2 sorption rate than that of the Li4SiO4 sorbent. Moreover, the LONS2 solid sorbent containing both Li3NaSiO4 and Li4SiO4 phases has potential for CO2 capture at high temperature.

Fe-Ni and Co-Fe-Ni catalysts were prepared by the wet impregnation method for the production of high-calorific synthetic natural gas. The influence of Ni addition to Fe and Co-Fe catalyst structure and catalytic performance was investigated. The results show that the increasing of Ni amount in Fe-Ni and Co-Fe-Ni catalysts increased the formation of Ni-Fe alloy. In addition, the addition of nickel to the Fe and Co-Fe catalysts could promote the dispersion of metal and decrease the reduction temperature. Consequently, the Fe-Ni and Co-Fe-Ni catalysts exhibited higher CO conversion compared to Fe and Co-Fe catalysts. A higher Ni amount in the catalysts could increase C1–C4 hydrocarbon production and reduce the byproducts (C5+ and CO2). Among the catalysts, the 5Co-15Fe-5Ni/γ-Al2O3 catalyst affords a high light hydrocarbon yield (51.7% CH4 and 21.8% C2–C4) with a low byproduct yield (14.1% C5+ and 12.1% CO2).

We chemically functionalized several plastic surfaces using an agarose film for applying a protein chip. The chip performance was affected by the surface energy of each plastic after oxygen-plasma cleaning; as a result, polystyrene and polyethylene terephthalate showed a higher signal-to-noise ratio than did polypropylene. We envision that this study will help to develop a way to build biochips.

It is well known that the variance of tally is biased in a Monte Carlo calculation based on the power iteration method. Several studies have been conducted to estimate the real variance. Among them, the batch method, which was proposed by Gelbard and Prael, has been utilized actively in many Monte Carlo codes because the method is straightforward, and it is easy to implement the method in the codes. However, there is a problem when utilizing the batch method because the estimated variance varies depending on batch size. Often, the appropriate batch size is not realized before the completion of several Monte Carlo calculations. This study recognizes this shortcoming and addresses it by permitting selection of an appropriate batch size. Keywords: Real variance, Monte Carlo, Batch method, Fission probability matrix, Apparent variance

Hybrid catalysts in a double-layered bed reactor were used to produce light C2–C4 paraffin hydrocarbons. Combinations of Fischer–Tropsch (FT) and cracking catalysts in a double-layered bed reactor configuration were studied. SAPO-34 and Ni-based cracking catalysts (hybrid catalyst) were used to convert C5+ into CH4 and C2–C4 paraffin hydrocarbons. Activity tests in the double-layered bed reactor at 10 bar and 300 °C and using a H2/CO feed gas ratio of 3.0 revealed that the hybrid catalyst showed lower C5+ and higher CH4 and C2–C4 selectivities than the FT catalyst alone. The Ni-based catalyst enabled additional CO conversion and CO2 methanation.