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1.
Seung Han Ryu Seil Kim Young-Tae Kwon Young Ki Park Sung-Oong Kang Hong-Baek Cho Yong-Ho Choa 《应用聚合物科学杂志》2020,137(8):48390
Here, we report a facile approach to electrostatically couple the surface charges of graphite nanoplate (GNP) fillers and poly(methyl methacrylate) (PMMA) polymer particles using ethylene maleic anhydride (EMA) copolymer as an electrostatic coupling agent. Our strategy involved switching the intrinsic repulsive electrostatic interactions between the directly exfoliated GNPs fillers and the PMMA particles to attractive electrostatic surface interactions for preparing core(PMMA)-shell (GNP) precursor in order to optimizing 3-dimensionally dispersed polymer nanocomposite. As a result, the electrical conductivity of the composites dramatically increased by a factor of 16.7 in the EMA-coupled GNP/PMMA composites compared with that of the EMA-free GNP/PMMA composites. In addition, the percolation threshold was also notably reduced from 0.32 to 0.159 vol% after electrostatic coupling of the GNPs fillers and PMMA particles. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48390. 相似文献
2.
Jongmin Lee Hongji Yoon Kyoung Soon Choi Seungkyu Kim Sehun Seo Jaesun Song Byeong‐Uk Choi Jiseung Ryu Sangwoo Ryu Jihun Oh Cheolho Jeon Sanghan Lee 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(39)
To develop strategies for efficient photo‐electrochemical water‐splitting, it is important to understand the fundamental properties of oxide photoelectrodes by synthesizing and investigating their single‐crystal thin films. However, it is challenging to synthesize high‐quality single‐crystal thin films from copper‐based oxide photoelectrodes due to the occurrence of significant defects such as copper or oxygen vacancies and grains. Here, the CuBi2O4 (CBO) single‐crystal thin film photocathode is achieved using a NiO template layer grown on single‐crystal SrTiO3 (STO) (001) substrate via pulsed laser deposition. The NiO template layer plays a role as a buffer layer of large lattice mismatch between CBO and STO (001) substrate through domain‐matching epitaxy, and forms a type‐II band alignment with CBO, which prohibits the transfer of photogenerated electrons toward bottom electrode. The photocurrent densities of the CBO single‐crystal thin film photocathode demonstrate ?0.4 and ?0.7 mA cm?2 at even 0 VRHE with no severe dark current under illumination in a 0.1 m potassium phosphate buffer solution without and with H2O2 as an electron scavenger, respectively. The successful synthesis of high‐quality CBO single‐crystal thin film would be a cornerstone for the in‐depth understanding of the fundamental properties of CBO toward efficient photo‐electrochemical water‐splitting. 相似文献
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Wireless Networks - With the increase in the number of mobile devices such as tablets and smart watches, mobile social networks (MSNs) provide great opportunities for people to exchange... 相似文献
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Ning An Yunhao Cai Hongbo Wu Ailing Tang Kangning Zhang Xiaotao Hao Zaifei Ma Qiang Guo Hwa Sook Ryu Han Young Woo Yanming Sun Erjun Zhou 《Advanced materials (Deerfield Beach, Fla.)》2020,32(39):2002122
Compared with inorganic or perovskite solar cells, the relatively large non-radiative recombination voltage losses (ΔVnon-rad) in organic solar cells (OSCs) limit the improvement of the open-circuit voltage (Voc). Herein, OSCs are fabricated by adopting two pairs of D–π–A polymers (PBT1-C/PBT1-C-2Cl and PBDB-T/PBDB-T-2Cl) as electron donors and a wide-bandgap molecule BTA3 as the electron acceptor. In these blends, a charge-transfer state energy (ECT) as high as 1.70–1.76 eV is achieved, leading to small energetic differences between the singlet excited states and charge-transfer states (ΔECT ≈ 0.1 eV). In addition, after introducing chlorine atoms into the π-bridge or the side chain of benzodithiophene (BDT) unit, electroluminescence external quantum efficiencies as high as 1.9 × 10−3 and 1.0 × 10−3 are realized in OSCs based on PBTI-C-2Cl and PBDB-T-2Cl, respectively. Their corresponding ΔVnon-rad are 0.16 and 0.17 V, which are lower than those of OSCs based on the analog polymers without a chlorine atom (0.21 and 0.24 V for PBT1-C and PBDB-T, respectively), resulting in high Voc of 1.3 V. The ΔVnon-rad of 0.16 V and Voc of 1.3 V achieved in PBT1-C-2Cl:BTA3 OSCs are thought to represent the best values for solution-processed OSCs reported in the literature so far. 相似文献
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Preparation and characterisation of an easily absorbabl Mg‐casein hydrolysate complex produced through enzymatic hydrolysis and ultrafiltration 下载免费PDF全文
Hye‐Jin Hong En‐jin Kim In‐Su Park Jung‐Ho Ryu Taegong Ryu Byoung‐Gyu Kim Kang‐Sup Chung 《International Journal of Food Science & Technology》2015,50(2):365-371
In this study, we synthesised a Mg‐casein hydrolysate complex that allowed the effective absorption of Mg. The type of enzyme (papain, alcalase 2.4 L, pepsin, trypsin) and the enzyme/substrate ratio for casein hydrolysis was optimised. When the enzyme/substrate ratio was 30%, the alcalase 2.4 L‐hydrolysate showed the highest Mg‐chelation efficiency, of 96.1%. To characterise and enhance the function of casein hydrolysate, we fractionated the casein hydrolysate according to molecular weight using ultrafiltration. The Mg‐chelation efficiency was increased with the decrease in the molecular‐weight range of the hydrolysate fractions. The smallest casein hydrolysate (fraction 5, 1 kDa<) is used for preparation of Mg‐casein hydrolysate complex. Synthesised Mg‐casein hydrolysate complex (fraction 5) exhibited 100% Mg solubility and 39.5% Mg bioavailability. These results indicated that the Mg‐casein hydrolysate remained a stable chelate during simulated gastro‐intestinal digestion in vitro. The Mg‐casein hydrolysate complex exhibited excellent antioxidant activity as well as Mg binding. 相似文献
8.
Seung‐Hun Ryu Dong‐Uk Park Eun Lee Soyoung Park So‐Yeon Lee Sungsu Jung Sang‐Bum Hong Jihoon Park Soo‐Jong Hong 《Indoor air》2019,29(5):735-747
Since around the year 2000, hundreds of people in Korea have developed humidifier disinfectant‐associated lung injury (HDLI). We collected all HD exposure‐related information from the field investigations into the locations in which the 1199 registered patients had used HD. Among the people who registered, 38% (1st round = 214, 2nd = 73, 3rd = 166) were confirmed as HDLI patients. Children aged under eight years old made up the highest proportion of HDLI cases (N = 279, 62%), followed by pregnant women (N = 31, 7%). One hundred thirty‐three (29%) of the confirmed HDLI patients died. Fifty‐seven percent of HDLI patients (N = 259) developed HDLI after <1 year of HD use. The number of HDLI patients who used only the Oxy Saksak HD brand was found to be 176 (39%), followed by the brands Cefu (N = 27, 6%) and Aekyung (N = 22, 5%). HD products containing only polyhexamethylene guanidine phosphate (PHMG‐P) were the most frequently used among HDLI patients (N = 234, 52%), followed by oligo (2‐(2‐ethoxy)ethoxyethyl) guanidinium (PGH) (N = 27, 6%) and a mixture of chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT) (N = 26, 6%). The average PHMG‐P inhalation level estimated from the patient group classified as suffering lung injury definitely associated with HD use was 145.1 μg/m3 (N = 91, SD = 395.1 μg/m3), higher than levels estimated from both the probable and possible HDLI patient groups. In conclusion, HD exposure‐related variables, including type of HD brand and estimated inhalation HD level, were associated with the risk of HDLI. 相似文献
9.
Jeong Chang Hee Ryu Haram Zhang Ting Lee Chi Ho Seo Han Geuk Han Sung Gu 《Food science and biotechnology》2018,27(5):1419-1427
Food Science and Biotechnology - Yogurt is a fermented dairy food produced by growth of lactic acid bacteria (LAB). Green tea is associated with beneficial health effects. Thus, the aim of this... 相似文献
10.
Seismic Fragility of Steel Piping System Based on Pipe Size,Coupling Type,and Wall Thickness 总被引:1,自引:0,他引:1
In this study, a probabilistic framework of the damage assessment of pipelines subjected to extreme hazard scenario was developed to mitigate the risk and enhance design reliability. Nonlinear 3D finite element models of T-joint systems were developed based on experimental tests with respect to leakage detection of black iron piping systems, and a damage assessment analysis of the vulnerability of their components according to nominal pipe size, coupling type, and wall thickness under seismic wave propagations was performed. The analysis results showed the 2-inch schedule 40 threaded T-joint system to be more fragile than the others with respect to the nominal pipe sizes. As for the coupling types, the data indicated that the probability of failure of the threaded T-joint coupling was significantly higher than that of the grooved type. Finally, the seismic capacity of the schedule 40 wall thickness was weaker than that of schedule 10 in the 4-inch grooved coupling, due to the difference in the prohibition of energy dissipation. Therefore, this assessment can contribute to the damage detection and financial losses due to failure of the joint piping system in a liquid pipeline, prior to the decision-making. 相似文献