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991.
Sung Ki Kim Young Jin Choi Won Kyu Kwak Kyu Sik Cho Jin Jang 《Electron Device Letters, IEEE》1999,20(1):33-35
A novel, coplanar, hydrogenated amorphous silicon (a-Si:H) thin-film transistor (TFT) was fabricated by depositing a triple layer consisting of a-Si:H, silicon-nitride, and a-Si:H. After patterning the top two layers in the gate stack, the devices were doped and a 30 nm Ni layer was deposited. The devices were then annealed for 1 h at 230°C to form self-aligned, low resistive Ni-silicide. The fabricated coplanar a-Si:H TFT exhibits a field effect mobility of 0.6 cm2/Vs, a threshold voltage of 2 V, a subthreshold slope of 0.4 V/dec, and an on/off current ratio of ~107 相似文献
992.
Amphiphilic urethane acrylate anionomer (UAA) chains exhibited very different solution properties in various solvents, such as water, dioxane, and dimethyl sulfoxide (DMSO). UAA chains showed a polyelectrolyte effect in a highly polar solvent, DMSO, but gave constant viscosity at various concentrations in aqueous solution, because of the microstructural difference of the UAA chain formed in solvents. In polar solvents (water and DMSO), the swelling of UAA networks prepared with water and dioxane strongly depended on the properties of the hydrophilic domains. In low and nonpolar solvents (dioxane and methylene chloride), the swelling of UAA networks was only dependent on the property of the hydrophobic segments. In the polar solvent medium, UAAG networks prepared with water exhibited greater swelling than UADG networks prepared with dioxane. Concerning swelling in a nonpolar solvent, however, UADG networks showed greater swelling than UAAG networks. This is because of the microstructural difference between these networks, which was confirmed by the mechanical property measurement. UAAG networks, having highly microphase‐separated structures, had higher modulus and transition temperatures than the UADG networks, because of the microstructural difference between UADG and UAAG networks. Both the UAAG and UADG networks take up two immiscible solvents simultaneously within their hydrophobic and hydrophilic domains. Equilibrium swelling ratio of these networks in two immiscible solvents strongly depends on their hydrophilic/hydrophobic balance that is controlled by the type of solvent used in the network synthesis. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 621–630, 2001 相似文献
993.
Free surface vortex control is vital in a pump sump system because the air absorbed by free surface vortex induces noise,vibration,and cavitation corrosion on the pumping system.In this study,the change of free surface vortex and air absorption in a pump intake has been investigated by the Volume of Fraction (VOF) method with steady multiphase flow model in order to represent the behavior of the free surface vortex exactly.The homogeneous free surface model is used to apply interactions of air and water.The results show that air intake by the free surface vortex motion can be visualized using the iso-sufface of air volume fraction.The vortices make an air column from the free surface to the pump intake.Also,it was found that the free surface vortex can be controlled by installing curtain walls. 相似文献
994.
Jin Hwan Lee Nam Suk KangSang-Ouk Shin Seong-Hyu ShinSea-Gyu Lim Duck-Yong SuhIn-Youl Baek Keum-Yong ParkTae Joung Ha 《Food chemistry》2009
The aim of this study was to isolate and identify the anthocyanins in the black seed coated soybean (cv. Cheongja 3, Glycine max (L.) Merr.) using reverse phase C-18 open column chromatography and high-performance liquid chromatography (HPLC) with diode array detection and electro spray ionization/mass spectrometry (DAD-ESI/MS) analysis, respectively. Anthocyanins were extracted from the coat of black soybeans with 1% TFA in methanol, isolated by RP-C-18 column chromatography, and their structures elucidated by 1D and 2D NMR spectroscopy. The isolated anthocyanins were characterised as delphinidin-3-O-glucoside (3), cyanidin-3-O-glucoside (5), petunidin-3-O-glucoside (6), pelargonidin-3-O-glucoside (7) and cyanidin (9). Furthermore, four minor anthocyanins were detected and identified as catechin-cyanidin-3-O-glucoside (1), delphinidin-3-O-galactoside (2), cyanidin-3-O-galactoside (4), and peonidin-3-O-glucoside (8) based on the fragmentation patterns of HPLC-DAD-ESI/MS analysis. 相似文献
995.
Acid Resistance and Molecular Characterization of Escherichia coli O157:H7 and Different Non‐O157 Shiga Toxin‐Producing E. coli Serogroups 下载免费PDF全文
Gwang‐Hee Kim Frederick Breidt Pina Fratamico Deog‐Hwan Oh 《Journal of food science》2015,80(10):M2257-M2264
The objective of this study was to compare the acid resistance (AR) of non‐O157 Shiga toxin‐producing Escherichia coli (STEC) strains belonging to serogroups O26, O45, O103, O104, O111, O121, and O145 with O157:H7 STEC isolated from various sources in 400 mM acetic acid solutions (AAS) at pH 3.2 and 30 °C for 25 min with or without glutamic acid. Furthermore, the molecular subgrouping of the STEC strains was analyzed with the repetitive sequence‐based PCR (rep‐PCR) method using a DiversiLabTM system. Results for a total of 52 strains ranged from 0.31 to 5.45 log reduction CFU/mL in the absence of glutamic acid and 0.02 to 0.33 CFU/mL in the presence of glutamic acid except for B447 (O26:H11), B452 (O45:H2), and B466 (O104:H4) strains. Strains belonging to serogroups O111, O121, and O103 showed higher AR than serotype O157:H7 strains in the absence of glutamic acid. All STEC O157:H7 strains exhibited a comparable DNA pattern with more than 95% similarity in the rep‐PCR results, as did the strains belonging to serogroups O111 and O121. Surprisingly, the DNA pattern of B458 (O103:H2) was similar to that of O157:H7 strains with 82% similarity, and strain B458 strain showed the highest AR to AAS among the O103 strains with 0.44 log reduction CFU/mL without glutamic acid. In conclusion, STEC serotypes isolated from different sources exhibited diverse AR and genetic subtyping patterns. Results indicated that some non‐O157 STEC strains may have higher AR than STEC O157:H7 strains under specific acidic conditions, and the addition of glutamic acid provided enhanced protection against exposure to AAS. 相似文献
996.
Jiyoung Kim Jung Nam Choi Joo Hee Choi Youn Soo Cha Maria John Muthaiya Choong Hwan Lee 《Molecular nutrition & food research》2013,57(10):1886-1891
As a nontargeted metabolomics approach, we investigated changes in the plasma metabolite levels in a mouse model of obesity induced by a high‐fat diet and fermented soybean product diet. We analyzed the plasma samples by using ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight mass spectrometry (UPLC‐Q‐TOF‐MS). In the present study, the animals were divided into four groups according to the diet type; normal fat diet control group (ND), high‐fat diet control group (HD), high‐fat diet plus 30% cooked soybean power (HD + S), and high‐fat diet plus 30% 72‐h fermented Cheonggukjang powder (HD + CGJ). To examine the changes in plasma metabolite levels because of high‐fat diet feeding, total cholesterol and triglyceride levels were measured. Total cholesterol and triglyceride levels were lower in the HD + S and HD + CGJ groups than in the ND group. According to partial least‐squares discriminant analysis (PLS‐DA), major metabolites contributing to the discrimination between each group were assigned as lipid metabolites in plasma, e.g., lyso‐phosphatidylcholines and phosphatidylcholines. Therefore, diets containing soy‐based food products, which are rich sources of isoflavonoids, might be helpful for controlling the lipid metabolism under high‐fat diet conditions. 相似文献
997.
Analysis of 1/f noise in LWIR HgCdTe photodiodes 总被引:2,自引:0,他引:2
Soo Ho Bae Sang Jun Lee Young Ho Kim Hee Chul Lee Choong Ki Kim 《Journal of Electronic Materials》2000,29(6):877-882
We study the 1/f noise currents and dark currents in LWIR HgCdTe photodiodes. The measured dark currents of the diodes processed
by post implantation annealing with different annealing times are analyzed using current model fitting methods. The different
dark current components, such as diffusion current, generation-recombination current, band-to-band tunneling current, and
trap assisted tunneling current, at various bias voltages can be separated from the measured dark currents. By the fitting
analysis, some physical parameters are extracted and different annealing effects can be explained by the parameters. The improvements
in diode characteristics by post implantation annealing can be explained by the changes of trap density, donor concentration,
minority carrier lifetime, and generation lifetime. The 1/f noise currents are measured over a wide range of reverse bias
voltages, and correlated with the extracted dark currents by superposition of the noise generated by the different dark current
mechanisms. It turns out that the band-to-band tunneling has a smaller correlation with the 1/f noise than other current components,
and the trap center seems to be responsible for the 1/f noise characteristics of the LWIR HgCdTe photodiodes. 相似文献
998.
999.
Anurupa A. Ghosh Dinesh Kumar Verma Gabriela Cabrera Kwadwo Ofori Karina Hernandez-Quijada Jae-Kwan Kim Joo Hee Chung Michael Moore Sung Hwan Moon Jong Bok Seo Yong-Hwan Kim 《International journal of molecular sciences》2022,23(8)
Parkinson’s disease (PD) is a progressive neurodegenerative motor disorder without an available therapeutic to halt the formation of Lewy bodies for preventing dopaminergic neuronal loss in the nigrostriatal pathway. Since oxidative-stress-mediated damage has been commonly reported as one of the main pathological mechanisms in PD, we assessed the efficacy of a novel NOX inhibitor from AptaBio Therapeutics (C-6) in dopaminergic cells and PD mouse models. The compound reduced the cytotoxicity and enhanced the cell viability at various concentrations against MPP+ and α-synuclein preformed fibrils (PFFs). Further, the levels of ROS and protein aggregation were significantly reduced at the optimal concentration (1 µM). Using two different mouse models, we gavaged C-6 at two different doses to the PD sign-displaying transgenic mice for 2 weeks and stereotaxically PFF-injected mice for 5 weeks. Our results demonstrated that both C-6-treated mouse models showed alleviated motor deficits in pole test, hindlimb clasping, crossbeam, rotarod, grooming, and nesting analyses. We also confirmed that the compound treatment reduced the levels of protein aggregation, along with phosphorylated-α-synuclein, in the striatum and ventral midbrain and further dopaminergic neuronal loss. Taken together, our results strongly suggest that NOX inhibition can be a potential therapeutic target for PD. 相似文献
1000.