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1.
Ahn Kyu-Hong Hwang Jong-Hyuk Song Kyung-Guen Jung Yong-Ho Cho Eul-Saeng Lim Byung-Ran Kim Kwang-Soo 《Metals and Materials International》2004,10(2):167-170
The performance of an attached growth wastewater treatment process was investigated in an effort to improve nitrogen removal
efficiency. Recycled Yakult (lactic acid fermentation drink) bottles made of polystyrene were used as a biofilm media. The
use of Yakult bottles as a biofilm media has been attempted by numerous researchers in Japan for the removal of solids and
organics. However, these studies focused only on the removal of solids and organics. This study extended their application
to the removal of nitrogen for domestic sewage treatment. Yakult media was placed in a reactor with 70% apparent reactor volume
in a conventional A/O process. The bottom of the Yakult media was removed, and randomly filled Yakult media were effectively
able to reduce the flow in tanks, resulting in an increase in the contact time between pollutants and microorganisms. With
higher HRT, the nitrogen removal efficiency was increased by up to 83% with 12 hr of HRT. Nitrification appeared to be the
limiting factor of nitrogen removal at an HRT that is less than 12 hr, indicating that the Yakult process requires more retention
time to achieve nitrification compared to other biofilm processes. The removal efficiencies of organics and solids were high
regardless of the change of operational parameters.
This article is based on a presentation in “The 7th Korea-China Workshop On Advanced Materials” organized by the Korea-China
Advanced Materials Cooperation Center and the China-Korea Advanced Materials Cooperation Center, held at Ramada Plaza Jeju
Hotel, Jeju Island, Korea on August 24–27, 2003. 相似文献
2.
Sungyoun Kim Hyejung Jung Kwang-Soo Kim In S. Kim 《Canadian Metallurgical Quarterly》2004,130(12):1475-1480
The treatment performance of sequential heterotrophic and autotrophic denitrification process was evaluated using synthetic wastewaters containing high nitrate concentrations. The effluents from two sequentially connected reactors, for heterotrophic denitrification and sulfur-based autotrophic denitrification, were analyzed for more than 200 days. Experimental results indicated that higher than 95% of the nitrate removal could be achieved with volumetric nitrate loading rates of 2.16, 3.24, and 4.32 kg/m3?d. The maximum denitrification rates, with 1,000 mgN/l influent nitrate concentrations, for the heterotrophic and sulfur-packed autotrophic reactors, were found to be 2.47 and 3.61 kg/m3?d, respectively. A sequential heterotrophic and autotrophic denitrification process is considered a good alternative for the sole autotrophic denitrification process, providing excellent nitrate removal, especially for nitrate-rich wastewaters with very low organic contents. 相似文献
3.
Park KS Baik KH Kim DP Woo JC No KS Lee K Do LM 《Journal of nanoscience and nanotechnology》2011,11(2):1625-1628
In this study, we present a spacer patterning technology for sub-30 nm gate template which is used for nano-scale MOSFETs fabrication. A spacer patterning technology using a poly-silicon micro-feature and a chemical vapor deposition (CVD) SiO2 spacer has been developed, and the sub-30 nm structures by conventional dry etching and chemical mechanical polishing are demonstrated. The minimum-sized features are defined not by the photolithography but by the CVD film thickness. Therefore, this technology yields a large-area template with critical dimension of minimum-sized features much smaller than that achieved by optical lithography. 相似文献
4.
[Correction Notice: An erratum for this article was reported in Vol 120(6) of Behavioral Neuroscience (see record 2006-22387-011). In the article "Anxiogenic-Like Effect of Chronic Corticosterone in the Light-Dark Emergence Task in Mice," by Paul Ardayfio and Kwang-Soo Kim (Behaviorial Neuroscience, 2006, Vol. 120, No. 2, pp. 249-256), the measurement unit of the corticosterone concentration on p. 250 (under the Drugs heading) was incorrect. The correct unit is μg/ml. The corrected sentence follows: "Corticosterone (Sigma, St. Louis, MO) was dissolved in ethanol, diluted, and administered via the drinking water at a final concentration of 0 or 35 μg/ml in 0.3% ethanol."] Chronic hypercortisolemia is a hallmark of neuroendocrine and psychiatric disorders, such as Cushing's disease and depression. Whether cortisol directly contributes to the altered mood and anxiety symptoms seen in these diseases remains unclear. To address this, the authors have modeled hypercortisolemia by administering corticosterone in the drinking water of female Swiss Webster mice for 17 or 18 days (13 mg/kg). Light-dark emergence, startle habituation, and startle reactivity were measured. Chronic but not acute treatment with corticosterone increased the latency to emerge into the light compartment, an anxiogenic-like effect. Chronic corticosterone treatment did not affect startle habituation, but did reduce startle reactivity. This study suggests that chronic hypercortisolemia may contribute to anxiety-related behavior in patients with Cushing's disease and depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Fiber-reinforced polymer (FRP) systems that have a strong resistance against long-term deformation must provide improved serviceability to reinforced concrete (RC) members under sustained loads. Consequently, there is a need to develop a method for accurately predicting the time-dependent behavior of RC beams that are externally bonded with FRPs. However, there are very few previous studies that have been carried out or experimental results available, on the time-dependent behavior of RC beams externally bonded with FRP. In order to enable a reasonable prediction, correlations should first be clarified between the stress–strain relationship of the concrete, the reinforcement and the FRP that changes over time. By using these correlations, deflections under sustained loads should then be forecast. In this study, RC beams were fabricated for this purpose. Carbon reinforced polymer (CFRP) and glass reinforced polymer (GFRP) materials were bonded to the tension face of the two respective RC beams. The beams were then placed under sustained loads for 300 days. For the specimens that were externally bonded with FRPs and for the conventional specimen, the strain of the compression and tension reinforcement and the strain of FRP and deflection were measured respectively for comparison. In order to theoretically predict the time-dependent behavior of the RC Beam externally bonded with FRPs, creep coefficients for concrete and shrinkage strains were calculated by using the CEB-FIP and the ACI-209 Codes. For the method used to forecast the stress–strain relationships of the concrete, reinforcement and FRPs that change over time were theoretically clarified and were then compared with the experimental results. The deflection of the RC Beams externally bonded with FRP was predicted by using the ACI 318 Standard, EMM, AEMM, Branson’s method, and Mayer’s method. They were also compared to the experimental results. Subsequently, in the case of RC Beams externally bonded with FRPs under sustained loads, the proposed method proved that it is possible to accurately predict long-term deformations. 相似文献
6.
Yuna Kim Hyanggi Ji Eunae Cho Nok-Hyun Park Kyeonghwan Hwang Wonseok Park Kwang-Soo Lee Deokhoon Park Eunsun Jung 《International journal of molecular sciences》2021,22(24)
Functional studies of organisms and human models have revealed that epigenetic changes can significantly impact the process of aging. Non-coding RNA (ncRNA), one of epigenetic regulators, plays an important role in modifying the expression of mRNAs and their proteins. It can mediate the phenotype of cells. It has been reported that nc886 (=vtRNA2-1 or pre-miR-886), a long ncRNA, can suppress tumor formation and photo-damages of keratinocytes caused by UVB. The aim of this study was to determine the role of nc886 in replicative senescence of fibroblasts and determine whether substances capable of controlling nc886 expression could regulate cellular senescence. In replicative senescence fibroblasts, nc886 expression was decreased while methylated nc886 was increased. There were changes of senescence biomarkers including SA-β-gal activity and expression of p16INK4A and p21Waf1/Cip1 in senescent cells. These findings indicate that the decrease of nc886 associated with aging is related to cellular senescence of fibroblasts and that increasing nc886 expression has potential to suppress cellular senescence. AbsoluTea Concentrate 2.0 (ATC) increased nc886 expression and ameliorated cellular senescence of fibroblasts by inhibiting age-related biomarkers. These results indicate that nc886 has potential as a new target for anti-aging and that ATC can be a potent epigenetic anti-aging ingredient. 相似文献
7.
8.
Seung-Won Lee Kwang-Soo Kim Hee-Soo Moon Jae-Pil Lee Hyun-Joong Kim Byung-Won Cho Won-Il Cho Jong-Wan Park 《Journal of power sources》2004,130(1-2):227-232
The electrochemical and structural characteristics of the metal oxide-coated spinel were investigated in the range of 2.5–4.2 V. Metal oxide coating on commercial spinel powder (LiMn2−xMxO4, M=Zr, Nikki, Japan) was carried out using the sol–gel method. Al2O3/(PtOx or CuOx)-coated spinel exhibited improved cyclability compared to bare spinel. Impedance analysis results indicated that electrochemical resistance value was not consistent with cycle performance. The improved cycle performance of metal oxide-coated spinel may be due to formation of a new Li2Mn4O9, Li2MnO3 phase, which is expected to have stability to phase transition (Jahn–Teller distortion). 相似文献
9.
Won-Bo Shim Kwang-Soo Ha Min-Gon Kim Jeong-Sook Kim Duck-Hwa Chung 《Food science and biotechnology》2014,23(6):2103-2108
Ochratoxin A (OTA), a mycotoxin classified as a potentially carcinogenic to humans, is slightly soluble in water. In this study, the transfer rate of OTA in herbal medicines to decoctions was investigated. Herbal medicine decoctions were prepared by boiling and autoclaving herbal medicines contaminated with OTA after soaking and not soaking in water. OTA amounts in decoctions and residues were analyzed using HPLC. Transfer of OTA (12.72–61.33%) from herbal medicines to decoctions was observed. Soaking and autoclaving steps enhanced the transfer rate of OTA to decoctions. The results meant that there is a potential risk for consumption of herbal medicine decoctions. Therefore, regular monitoring for mycotoxins, including OTA, in herbal medicines and proper management to ensure the safety of herbal medicines is necessary to protect consumers. 相似文献
10.
Dong-Pyo Kim Jong-Chang Woo Kyu-Ha Baek Kun-Sik Park Kijun Lee Kwang-Soo Kim Lee-Mi Do 《Vacuum》2011,86(4):380
We investigated the N2 additive effect on the etch rates of TiN and SiO2 and etch profile of TiN in N2/Cl2/Ar adaptively coupled plasma (ACP). The mixing ratio of Cl2 and Ar was fixed at 75 and 25 sccm, respectively. The N2 flow rate was increased from 0 to 9 sccm under the constant pressure of 10 mTorr. As N2 flow rate was increased in N2/Cl2/Ar plasma, the etch rate of TiN was linearly increased, but that of SiO2 was increased non-monotonically. The etch profile and the compositional changes of TiN was investigated with field emission-scanning electron microscope (FE-SEM), FE-Auger electron spectroscopy (FE-AES) and x-ray photoelectron spectroscopy (XPS). When 9 sccm N2 was added into Cl2/Ar, a steep etch profile and clean surface of TiN was obtained. In addition, the signals of TiN and Ti were disappeared in FE-AES and XPS when N2 additive flow into Cl2/Ar was above 6 sccm. From the experimental data, the increase in TiN etch rate was mainly caused by the increase of desorption and evacuation rate of etch by products because of the increased effective pumping speed. The etch mechanism of TiN in N2/Cl2/Ar ACP plasma can be concluded as the ion enhanced chemical etch. 相似文献