• Title/Summary/Keyword: Retention time

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Assessment of Hydraulic Behavior and Water Quality Variation Characteristics in Underground Reservoir (지하저수조의 수리적 거동과 수질변화 특성 평가)

  • Lee, H.D.;Bae, C.H.;Kim, J.H.;Hwang, J.W.;Hong, S.H.
    • Journal of Korean Society on Water Environment
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    • v.21 no.1
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    • pp.52-58
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    • 2005
  • The assessment on characteristics of hydraulic behavior and water quality variations of underground reservoirs of buildings were studied. Firstly, it was thought that underground reservoir capacities($m^3$) of buildings should be not determinated by the uniform and same methods but be estimated on the basis of the dwelling areas on dominated households and their residential characteristics, because these characteristics influence significantly on actual water usages and patterns of buildings. Secondly, it was likely that the average reduction rate of residual chlorine in underground reservoirs were affected from the their capacities, because the average reduction rate of residual chlorine in underground reservoirs under $1,000m^3$ was 43 percent, on the other hand, that rate of underground reservoirs over $1,000m^3$ was 60 percent. Thirdly, through the field investigation, the retention time of drinking water in underground reservoirs were in the range from 0.3 day to 3.9 day. In addition to, the average reduction rate of residual chlorine were depended largely on the retention time of drinking water. When the retention time was under 24 hours, the average reduction rate of residual chlorine was 45 percent, and in case of over 24 hours, was 49 percent. Fourth, water level in underground reservoirs was averagely varied in the range from 0.1 m to 2.65 m at the height of underground reservoirs. If considered actual height of underground reservoirs, 37.6 percent of the height of underground reservoirs was only used. Consequently, the frequency of the inflow and outflow of drinking water in underground reservoir were very increased, and had an effect on the reduction of residual chlorine. Lastly, the investigations on hydraulic structure characteristics of underground reservoirs inside showed the locations of inflow and outflow of drinking water almost were in the opposite direction. And some buildings had several baffles in the middle. Nevertheless, their installations had no beneficial for the improvement of water quality.

Ameliorating Effects of Cheongnoemyeongsin-hwan on Learning and Memory Impairment Induced by Cerebral Hypoperfusion in Rats (청뇌명신환(淸腦明神丸)이 뇌혈류저하 흰쥐의 학습 및 기억 장애 개선에 미치는 영향)

  • Chang, Suk Hee;Hwang, Won Deuk
    • Herbal Formula Science
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    • v.25 no.1
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    • pp.69-87
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    • 2017
  • Objectives : Cheongnoemyeongsin-hwan (CNMSH) is a herb medicine to treat cognitive impairment. This study was investigated the effects of CNMSH on learning and memory impairment induced by cerebral hypoperfusion. Cerebral hypoperfusion was produced chronically by permanent bilateral common carotid artery occlusion (BCCAO) in rats. Methods : CNMSH was administered orally once a day (250 mg/kg) for 28 days starting at 4th week after the BCCAO. The acquisition of learning and the retention of memory were tested on 9th week after the BCCAO using the Morris water maze. In addition, effect of CNMSH on neuronal apoptosis and ${\beta}-amyloid$ accumulation in the hippocmapus was evaluated with immunohistochemistry and Western blotting. Results : 1. CNMSH and ChAL significantly shortened the escape latencies on the 2nd day of acquisition training trials. 2. ChAL significantly prolonged the swimming time spent in the target and peri-target zones and CNMSH also significantly prolonged the swimming time spent in the peri-target zone. 3. CNMSH and ChAL significantly increased the number of target heading in the retention test. 4. ChAL significantly shortened the time of the 1st target heading in the retention test, but CNMSH insignificantly shortened the time of that. 5. CNMSH and ChAL significantly increased the memory score in the retention test. 6. CNMSH and ChAL significantly attenuated the reduction of CA1 neurons, but insignificantly attenuated the reduction of CA1 thickness. 7. CNMSH and ChAL significantly attenuated the up-regulation of Bax expression in the CA1 of hippocampus. 8. CNMSH and ChAL significantly attenuated the up-regulation of cascapse-3 expression in the CA1 of hippocampus. 9. CNMSH and ChAL significantly attenuated the ${\beta}-amyloid$ accumulation in the CA1 of hippocampus. 10. CNMSH and ChAL significantly attenuated the up-regulation of APP expression in the CA1 of hippocampus. 11. CNMSH and ChAL significantly attenuated the up-regulation of BACE-1 expression in the CA1 of hippocampus. Conclusions : The results show that CNMSH attenuates neuronal apoptosis and ${\beta}-amyloid$ accumulation in the hippocampus and alleviates the impairment of learning and memory produced by chronic cerebral hypoperfusion. These results suggest that CNMSH may be a beneficial medicinal herb to treat cognitive impairment associated with neurodegenerative diseases.

A Study on Discriminative Criteria of 6 Kinds of Achyranthis Radix Using HPLC/DAD;Isolation and Identification of 20-hydroxyecdysone from Aclryranthes japonica $N-{AKAI}$ and Comparison of Patterns of Achyranthis Radix from Different Locations by HPLC (HPLC/DAD를 이용한 6종(種) 우슬(牛膝)의 분류기준 연구;우슬(牛膝)(쇠무릎, Achyranthes japonica $N_{AKAI}$)로부터 20-hydroxyecdysone 분리.동정 및 산지별 우슬의 HPLC 패턴 비교)

  • Kim, Jeong-Hi;Kim, Jong-Mun;Kang, Dae-Hoon
    • The Korea Journal of Herbology
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    • v.23 no.1
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    • pp.109-116
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    • 2008
  • Objectives : This study was performed to investigate the discriminative criteria of 6 kinds of Achyranthis Radix by HPLC/DAD. Methods : 20-hydroxyecdysone is isolated by silica gel column chromatography ($CHCl_3$:MeOH, 7:1-1:1 v/v) and identified by nuclear magnetic resonance, A high-performance liquid chromatographic method with diode array detection was used to identify 20-hydroxyecdysone in A. japonica. The analysis was performed using $C_{18}$ column with isocratic elution consisted of 18% acetonitrile and 82% water and the detection was carried out by DAD at 254 nm. 6 kinds of Achyranthis Radix from different locations were extracted in MeOH. Each extracts was analyzed by HPLC in same condition as used in analysis of 20-hydroxyecdysone. The identities of each extracts were determined by comparing the retention time and UV spectrum with that of reference compound. Results : 1. A. japonica and A. bidentata showed the similar patterns of HPLC chromatogram and 20-hydroxycedysone was present in both of them because the peaks having the same retention time and UV spectrum as 20-hydroxyecdysone were shown in the HPLC chromatograms of A. japonica and A. bidentata 2. Cyathula officinalis and C. capitata showed the similar patterns of HPLC chromatogram. The peak having the same retention time and UV spectrum as 20-hydroxyecdysone was shown in the HPLC chromatogram of C. capitata but not shown in the HPLC chromatogram of C. officinalis. 3. Two species of medicinal drugs from Sacheon province showed similar patterns of HPLC chromatogram. Achyranthis Radix from Sacheon(wild) did not have 20-hydroxycedysone but Achyranthis Radix from Sacheon(cultivated) showed the peak having the same retention time as 20-hydroxyecdysone but UV spectrum of the peak was different from that of 20-hydroxyecdysone. Conclusions : These results suggested that 20-hydroxyecdysone could be the discriminative criteria for Achyranthis Radix contain 20-hydroxyecdysone though they belong to different genus and species. And the patterns of HPLC chromatogram also could be the discriminative criteria as the different species of Achyranthis Radix belonging to the same genus showed similar patterns of HPLC chromatogram.

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Effect of Heat Treatment on Properties of Tungsten Embolization Coils (텅스텐 색전코일의 특성에 미치는 열처리 효과)

  • Son, Ung-Hui;Hong, Sun-Hyeong;Sin, Gyeong-Min;Lee, Yun-Sin;Park, Jae-Hyeong
    • Journal of Biomedical Engineering Research
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    • v.19 no.4
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    • pp.333-339
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    • 1998
  • The effect of heat treatment conditions on the properties of tungsten(W) embolization coils has been evaluated. The W embolization coils were fabricated by coiling the primary W coil with a diameter of 30.mm on a alumina rod mandrel with a diameter of 2.92mm. The secondary coils were then heat treated at 475$^{\circ}C$and 600$^{\circ}C$ for various heat treatment time ranging from 5 minutes to 36hours. The pitch distance, diameter and shape retention capability of the W embolization coils were characterized after the heat treatment. The pitch distance of the W embolization coils increased with the heat treatment time. The diameter of W emboliazation coils decreased continuously with heat treatment time. The shape retention capability of the W embolization coils increased with the heat treatment time due to an increase in elasticity by formation of tungsten oxide film on W coil surface during the heat treatment. The heat treatment condition of W embolization Col at 600$^{\circ}C$ for 20 minute was considered desirable based on the optimization of the shape retention capability, pitch distance and secondary coil diameter after heat treatment.

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Evaluation of Operational Options of Wastewater Treatment Using EQPS Models (EQPS 모델을 이용한 하수처리장 운전 평가)

  • Yoo, Hosik;Ahn, Seyoung
    • Journal of the Korean Society of Urban Environment
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    • v.18 no.4
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    • pp.401-408
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    • 2018
  • EQPS (Effluent Quality Prediction System, Dynamita, France) was applied to analyze the appropriateness of the design of a bioreactor in A sewage treatment plant. A sewage treatment plant was designed by setting the design concentration of the secondary clarifier effluent to total nitrogen and total phosphorus, 10 mg/L and 1.8 mg/L, respectively, in order to comply with the target water quality at the level of the hydrophilic water. The retention time of the 4-stage BNR reactor was 9.6 hours, which was 0.5 for the pre-anoxic tank, 1.0 for the anaerobic tank, 2.9 for the anoxic tank, and 5.2 hours for the aerobic tank. As a result of the modeling of the winter season, the retention time of the anaerobic tank was increased by 0.2 hours in order to satisfy the target water quality of the hydrophilic water level. The default coefficients of the one step nitrification denitrification model proposed by the software manufacturer were used to exclude distortion of the modeling results. Since the process modeling generally presents optimal conditions, the retention time of the 4-stage BNR should be increased to 9.8 hours considering the bioreactor margin. The accurate use of process modeling in the design stage of the sewage treatment plant is a way to ensure the stability of the treatment performance and efficiency after construction of the sewage treatment plant.

Analysis on effect of heavy metal and Retention time to nitrification using industrial wastewater (중금속과 체류시간이 산업단지하수 질산화에 미치는 영향)

  • Im, Jiyeol;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.20 no.4
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    • pp.390-397
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    • 2018
  • The Municipal Wastewater Treatment Plant(MWTP), located industrial estate, has a problem of decreasing nitrification efficiency. In this research, it was analyzed that effect of heavy metals and retention time to nitrification based on operational result of laboratory scale reactors. And suggest improving MWTP operation method for increasing nitrification efficiency based on findings. According to operational result, laboratory scale reactor shows over 60% nitrification efficiency over hydraulic retention time(HRT) 0.5 day. However, the nitrification efficiency of S MWTP(high heavy metal concentration) sample was lower than that of A MWTP(low heavy metal concentration) sample in same operational condition. The main reason was heavy metals in industrial wastewater. This heavy metals was acted as inhibitor to nitrifier in reactors. So, activity of nitrifier was analyzed based on specific nitrification rate(SNR). The SNR of S MWTP sample shows 0.13 ~ 0.21 mg NH4/gMLSS/hr and that of A MWTP sample shows 0.74 mg NH4/gMLSS/hr. As a result, the activity of nitrifier of S MWTP was lower than that of A MWPT. In other words, retrofit methods for improving nitrification efficiency in MWTPs located industrial estate were that to increase retention time in biological treatment process or to pretreat heavy metal before being injected biological treatment process.

Mucociliary Clearance in the Children with Bronchial Asthma (기관지 천식 환아에서의 점액섬모 청소율(Mucociliary Clearance))

  • Lee, Myung-Hyun;Sun, Yong-Han;Nam, Seung-Gon;Koh, Young-Yull;Chung, June-Key
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.2
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    • pp.173-181
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    • 1996
  • Background : Several studies have suggested that impaired mucociliary clearance plays a role in the pathophysiology of bronchial asthma. Cough productive of mucoid sputum is common, and mucous plugs in the airways are frequently observed. These clinical features are in keeping with the histologic lesions of asthma, which involve primarily the epithelial and mucous-producing structures of the conducting airways. Some studies have shown that the mucociliary clearance is impaired in adult asthma, but it has not been studied in childhood asthma. The objectives of this study were to examine whether the mucociliary clearance is impaired in childhood asthma and to estimate the degree of impairment in comparison with that of immotile cilia syndrome. Method : Thirteen children with mild stable asthma and eight patients with immotile cilia syndrome completed this study. Ten healthy children were recruited as a normal control group. The whole-lung mucociliary clearance was measured by the radioaerosol technique. Aerosols, tin colloid particles tagged with the radionuclide technetium-99m($^{99m}Tc$), were generated by means of nebulizer, and inhaled via a mouthpiece. The retention of radioactivity was measured at 30, 60, 90 and 120 minutes by gamma camera, and mucociliary clearance was calculated as percent retention at each time. Results: 1) In each subject, the percent retention decreased variably with the lapse of time. 2) The percent retention of radionuclide decreased at each time in order of normal control, bronchial asthma and immotile cilia syndrome and the percent retention of immotile cilia syndrome was significantly higher than that of normal control at each time(p<0.05). 3) At two hours, the percent retention of bronchial asthma($65.0{\pm}1.8$(SE)%) was significantly higher than that of the normal control($54.4{\pm}3.5%$, p<0.05), and significantly lower than that of immotile cilia syndrome($73.3{\pm}1.4%$, p<0.01). 4) When the percent retention was analyzed according to $PC_{20}$ in the children with bronchial asthma, they had no relationship with each other. Conclusion: Mucociliary clearance in the children with bronchial asthma was significantly lower than normal control. This finding indicates that impaired mucociliary clearance operates in childhood asthma as well, and suggests that it may be one contributing factor in the pathogenesis of asthma. The degree of impairment, however, was not so severe as immotile cilia syndrome.

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Improvement of effluent water quality by sludge aeration at the conventional drinking water treatment plant (정수장 슬러지 폭기를 통한 방류수 수질 개선)

  • Choi, Ilgyung;Shin, Changsoo;Beak, Inho;Lim, Jaecheol;Jeong, Chanwoo;Lee, Sungjin;Park, Jungwook
    • Journal of Korean Society of Water and Wastewater
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    • v.28 no.2
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    • pp.249-255
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    • 2014
  • So many drinking water treatment plants are under various difficulties by new reinforced effluent standards. Since the target turbidity, much higher than annual average, for designing sludge thickener have to be set to confront high turbidity season, the sludge at thickener should be put up for a long time during usual days. So the soluble manganese and chloroform may be formed under the anaerobic environment in the sludge thickener when the sludge retention time is longer with low turbidity. This phenomenon results in difficulties to keep regulatory level of the discharged effluent. For an effort to overcome the problems, a sludge aeration was successfully implemented into the thickening process. As a result, the final effluent quality and sludge volume were much improved; 41 % of manganese, 62 % of chloroform and 35 % of sludge volume. Additionally, effluent quality was improved ; 61 % of Manganese on aeration with pH control and we could make sure of stability effluent quality despite a long sludge retention time. We recommended the standard of installation sludge aeration equipment to nationally supply water treatment plant under effluent water quality problem ; Manganese, Chloroform, etc.

Genotypic and Environmental Effects on Flour Properties in Korean Winter Wheat

  • Hong, Byung-Hee;Park, Chul-Soo;Baik, Byung-Kee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.1
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    • pp.1-12
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    • 2002
  • Flour characteristics of Korean winter wheat grown in Suwon in 1997 and 1998, and in Suwon and Deokso in 1998 were evaluated. Korean winter wheat cultivars were significantly influenced by years and locations in flour properties such as ash content, protein content, damaged starch content, starch swelling volume and power. Protein content was highly correlated with starch damage and alkaline water retention capacity. There were highly significant correlations between mixing time of mixograph and SDS sedimentation volume. Swelling properties of flour and starch were highly correlated with pasting properties of flour and starch, respectively. Compared to commercial flours for baking, Alchanmil, Gobunmil, Keumkangmil and Tapdongmil showed similar protein content, SOS sedimentation volume and mixograph mixing time. Eunpamil, Geurumil, Olgeurumil, Suwon 258, Suwon 261, Suwon 265, Suwon 275, Suwon 276, Suwon 277, Suwon 278 and Urimil had similar values to commercial noodle flours in SDS sedimentation volume. Alchanmil, Olgeurumil, Suwon 274, Suwon 275, Suwon 276 and Urimil showed higher swelling and pasting properties than the others. Chokwang, Olgeurumil, Suwon 277 and Urimil were similar to commercial cookie flours. Friabilin-absence lines showed higher protein content and starch damage than those of friabilin-presence lines. Absence lines of 1D$\times$2.2 + 1Dy12 subunit in high molecular weight glutenin subunits showed higher SDS sedimentation volume and mixing time of mixograph than those of presence lines.

Optimum loading capacity and nitrification characteristics of the swine wastewater treatment process using soil microbe (토양미생물을 이용한 축산폐수 처리공정의 적정부하율과 질산화공정의 특성)

  • Ha, Jun-Soo;Shin, Nam-Cheol
    • Korean Journal of Environmental Agriculture
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    • v.19 no.2
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    • pp.183-187
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    • 2000
  • Removal rate of nitrogen compound containing swine wastewater was 97 percent in case of high loading rate treatment of swine wastewater at studies for process development using soil microorganism. Minimum hydraulic retention time(HRT) for nitrification process was 11 days and solid retention time was 25 days. Nitrification was between 5 and 11 days but this time $NO_2-N$ was remained. Reactor condition was injured to nitrosomonas according to pH, $NO_2\;^--N$, and $NH_3\;^--N$ concentration but this condition was recover to pH controlling.

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