• 제목/요약/키워드: pH (mV)-time profile

검색결과 9건 처리시간 0.023초

생물학적 축산폐수 처리공정의 자동제어 방법 및 제어 인자의 안정성 (Real-time Control of Biological Animal Wastewater Treatment Process and Stability of Control Parameters)

  • 김원용;정재현;라창식
    • Journal of Animal Science and Technology
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    • 제46권2호
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    • pp.251-260
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    • 2004
  • SBR 처리공정의 자동제어 인자로서의 ORP, pH, DO의 안정성과 유용성을 비교 평가하였다. 시스템 운전동안 ORP와 pH(mV)-time profile 상에서 요염물질의 특이적인 변화시점을 나타내는 NBP와 NKP가 잘 나타났으며 이 시점은 MSC(moving slope change)를 이용하여 쉽게 인식될 수 있는 것으로 밝혀졌다. 그러나 부하량과 포기량 혹은 시스템 OUR이 불균형일 때는 DO나 ORP-time profile 상에서 NBP로 잘못 인식될 수 있는 가짜 제어시점이 여러 번 발생하거나 혹은 제어시점으로 인식할만한 변화가 전혀 발생하지 않음을 알 수 있었다. 그러나 pH(mV)-time profile에서는 어떤 운전조건과 상태에서도 항상 뚜렷한 NBP가 발생하고 MSC를 이용한 제어시점 인식이 가능함을 알 수 있었다. 따라서 호기적 처리과정 중의 시스템 진단과 자동제어 인자로 ORP나 DO 보다 pH(mV)가 안정적임을 알 수 있었다. 반면 무산소 상태의 모니터나 제어에 있어서는 pH(mV)-time profile에서 NKP를 안정적으로 인식하는 데에는 한계가 있었으나 ORP에서는 매우 안정적인 것으로 나타나 무산소 처리과정의 진단/제어인자로는 ORP가 다른 인자들 보다 유용함을 알 수 있었다. 이러한 결과로 미뤄 SBR 공정의 안정적인 자동제어를 위해서는 ORP 혹은 pH(mV)를 단독으로 이용하는 것 보다는 병용하는 것이 바람직하며, 이러한 자동제어기술은 유입수내 오염물질의 농도 변이와 운전여건에 상관없이 항상 오염물질의 완전제거를 가능케 함은 물론 처리시간 및 처리용량의 최적화를 위한 실용적 기술이 될 것으로 판단된다.

가축분뇨처리공정의 자동제어 인자 신뢰성 평가 및 적정 외부탄소원 공급량 지표 확립 (Estimation of Reliability of Real-time Control Parameters for Animal Wastewater Treatment Process and Establishment of an Index for Supplemental Carbon Source Addition)

  • 박재인;라창식
    • Journal of Animal Science and Technology
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    • 제50권4호
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    • pp.561-572
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    • 2008
  • 다양한 조건하에서 가축분뇨처리공정을 운전하면서 각 자동제어 인자의 반응을 분석하고 ORP, DO, pH(mV)-time profile를 이용한 자동제어 신뢰성을 평가하였다. 또한 무산소 조건에서의 잔존 유기물 및 미생물 자기산화에 의한 탈질율을 고려한 적정 외부탄소원 공급량 지표를 파악하였다. 실험은 45L의 유효용적을 지닌 실험실 규모의 SBR 공정을 이용하여 수행되었다. ORP-와 pH(mV)-, DO-time profile 상에서 완전질산화를 의미하는 NBP가 뚜렷하게 발현하던 중 NH4-N의 낮은 부하와 고농도 NOx-N 함유 폐수의 유입 및 불충분한 무산소 조건 제공이 이루어졌을 때 ORP-와 DO-time profile 상에서 NBP가 사라지기 시작하였으며 NOx-N의 지속적인 증가에 의해 ORP 값의 민감성이 둔화되기 시작하였다. 그러나 pH(mV)-time profile은 항상 일정한 변화패턴을 유지하면서 암모니아성 질소의 완전 질산화가 이루어졌을 때 뚜렷한 NBP를 발현하였다. NOx-N/NH4-N의 비가 80:1 수준까지 높아지는 조건하에서도 pH(mV)- time profile상에서의 이러한 안정적 NBP의 발현은 지속되었으며 발현되는 NBP는 MSC(Moving Slope Change)의 변화 패턴을 추적함에 의해 인식되도록 프로그램 할 수 있었다. pH(mV)-time profile에서의 NBP의 발현과 MSC를 이용한 자동제어시점 인식은 반응조내 NOx-N 농도가 무려 300mg/L 이상의 수준에서도 안정적이었다. 유기물 농도에 따른 자동제어 인자의 반응을 분석한 시험에서도 반응조내 유기물의 농도가 STOC 기준 약 10,000mg/L 수준으로 증가함에도 불구하고 pH(mV)-time profile 상에서의 이러한 NBP 발현은 지속되었으며 고농도 유기물 축적 하에서도 동일한 자동제어 알고리즘이 이용될 수 있음을 알 수 있었다. 잔존 유기물과 미생물 자기산화에 의한 탈질율은 약 0.4mg/L.hr로 분석되었으며 안전지수 0.1을 도입하여 산출된 NOx-N 기준 적정 외부탄소원 공급량은 0.83 STOC/NOx-N으로 파악되었다.

ORP profile을 이용한 연속 회분식 반응기(Sequencing Batch Reactor)에서 무산소공정 추론 (Inference of Sequencing Batch Reactor Process using Oxidation Reduction Potential)

  • 심문용;부경민;임정훈;우혜진;김창원
    • 한국환경과학회지
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    • 제13권3호
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    • pp.245-250
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    • 2004
  • The SBR(Sequencing Batch Reactor) process is ideally suited to treat high loading wastewater due to its high dilution rate. SBR operates by a cycle of periods consisting of filling, reacting, settling, decanting and idling. The react phases such as aeration or non-aeration, organic oxidation, nitrification, denitrification and other bio-logical reactions can be achieved in a reactor. Although the whole reactions can be achieved in a SBR with time distributing, it is hard to manage the SBR as a normal condition without recognizing a present state. The present state can be observed with nutrient sensors such as ${NH_{4}}^{+}-N$, ${NO_{2}}^{-}-N$, ${NO_{3}}^{-}-N} and ${PO_{4}}^{ 3-}-P.$ However, there is still a disadvantage to use the nutrient sensors because of their high expense and inconvenience to manage. Therefore, it is very useful to use common on-line sensors such as DO, ORP and pH, which are less expensive and more convient. Moreover, the present states and unexpected changes of SBR might be predicted by using of them. This study was conducted to get basic materials for making an inference of SBR process from ORP(oxidation reduction potential) of synthetic wastewater. The profiles of ORP, DO, and pH were under normal nitrification and denitrification were obtained to compare abnormal condition. And also, nitrite and nitrate accumulation were investigated during reaction of SBR. The bending point on ORP profile was not entirely in the low COD/NOx ratio condition. In this case, NOx was not entirely removed, and minimum ORP value was presented over -300mV. Under suitable COD/NOx ratio which complete denitrification was achieved, ORP bending point was observed and minimum ORP value was under -300m V. Under high COD/NOx ratio, ORP bending point was not detected at the first subcycle because of the fast denitrification and minimum ORP value was under -300mV at the time.

NEAR-IR PHOTOMETRIC AND OPTICAL SPECTROSCOPIC STUDY OF THE FU ORIONIS OBJECT V582 AURIGAE

  • OH, HYUNG-IL;YOONY, TAE SEOG;SUNG, HYUN-IL
    • 천문학논총
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    • 제30권2호
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    • pp.269-270
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    • 2015
  • We carried out near-IR photometric and optical spectroscopic observations of V582 Aur, which is a FU Orionis type object, to investigate any periodic and/or aperiodic variations. We obtained light curves on the scale of a night and a year, in J, H and Ks bands with KASINICS (KASI Near Infrared Camera System) attached to the BOAO (Bohyun-san Optical Astronomy Observatory) 1.8-m reflector in Youngcheon, South Korea and examined photometric variations on the two time scales. So far we have not found any periodic brightness variations on the scale of a night. On the other hand, we have found that there seems to be a periodic brightness variation with a period of approximately 45 days. In addition, high-resolution optical spectroscopic observations of V582 Aur were performed from February 2013 to May 2014 with the high-resolution echelle spectrograph BOES attached to the BOAO 1.8-m reflector. We analyzed several spectral lines to understand the physical state of V582 Aur. The P Cyg profiles are clearly shown in the $H{\alpha}$ line and Na I D line.

Effects of wilting and additives on the ensiling quality and in vitro rumen fermentation characteristics of sudangrass silage

  • Wan, Jiang Chun;Xie, Kai Yun;Wang, Yu Xiang;Liu, Li;Yu, Zhu;Wang, Bing
    • Animal Bioscience
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    • 제34권1호
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    • pp.56-65
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    • 2021
  • Objective: This study was conducted to investigate the effects of molasses and Lactobacillus plantarum on the ensiling quality and in vitro rumen fermentation of sudangrass silage prepared with or without wilting. Methods: The ensiling experiment, measured with 3 replicates, was carried out according to a 2×4 (wilted stages×additives) factorial treatment structure. Dry matter of the fresh (210 g/kg fresh matter) or wilted (305 g/kg fresh matter) sudangrass were ensiled (packed into 5.0-L plastic jars) without additive (control) or with molasses (M), Lactobacillus plantarum (LP), or molasses + Lactobacillus plantarum (M+LP). After 60 days of ensiling, the silages were analyzed for the chemical, fermentation, and in vitro characteristics. Results: After 60 days of ensiling, the fermentation parameters were affected by wilted, the additives and the interactions of wilted with the additives (p<0.05). The M+LP treatment at wilted had higher lactic acid levels and V-score (p<0.05) but lower pH values and butyric acid concentrations than the other treatments. In comparison with sudangrass before ensiling, after ensiling had lower dry matter and higher non-fibrous carbohydrate. The in vitro gas production, in vitro dry matter digestibility, in vitro crude protein digestibility, and in vitro acid fiber detergent digestibility changed under the effects of the additives. Significant interactions were observed between wilted and the additives in terms of in vitro gas production at 48 h, asymptotic gas production, gas production rate, half time, and the average gas production rate. The total volatile fatty acid levels in the additive treatments were higher than those in the control. Conclusion: Wilting and supplementation with molasses and Lactobacillus plantarum had the ability to improve the ensiling quality and in vitro nutrient digestibility of sudangrass silage. The M+LP treatment at wilted exhibited the strongest positive effects on silage quality and in vitro ruminal fermentation characteristics.

Antidiabetic activity of Argyreia speciosa (sweet) (Burm.f.)Boj. in normoglycemic and Streptozotocin-induced diabetic rats

  • Habbu, P.V.;Mahadevan, K.M.;Kulkarni, V.H.;Marietta, P.;Pratap, V.;Thippeswamy, B.S.;Veerapur, V.P.
    • Advances in Traditional Medicine
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    • 제10권2호
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    • pp.90-102
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    • 2010
  • Effect of ethanol (ASE) and water (ASW) extracts of Argyreia speciosa on blood glucose and lipid profile was investigated in normoglycemic and Streptozotocin (STZ)-induced diabetic animals. In oral glucose and sucrose tolerance test, treatment with ASE and ASW (100 and 200 mg/kg) and Glidenclamide (10 mg/kg) significantly improved the glucose and sucrose tolerance in normal animals. In addition, respective treatment for fifteen-day resulted in significant percentage reduction in serum glucose (SG) ie., 30.39% (lower dose of ASE) and 33.21% (higher dose of ASW). In standardized STZ (50 mg/kg, iv)-induced diabetic rats, a single dose of ASE and ASW treatment exhibited reduction in SG levels at different time intervals compared to basal levels. Administration of both the doses of ASE and ASW for fifteen-day days exhibited greater percentage reduction in glycemia (24.6%, 24.7%, 23.9% and 21.9% respectively) and also ameliorated restored to near normal value of all tested lipid parameters. Further, treatment also exhibited significantly improved glucose tolerance over the period of 120 min compared to diabetic control group. Eventhough treatment failed to increase serum insulin levels significantly but peripheral utilization of insulin was increased as evident by insulin tolerance test. Taken together, present study supports the traditional usage of title plant in the treatment of diabetes mellitus.

음이온성 리포솜의 방출 거동과 안정성 (Release Profile and Stability of Anionic Liposomes)

  • 남다은;한희동;박윤정;김윤아;신병철
    • Journal of Pharmaceutical Investigation
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    • 제34권4호
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    • pp.305-310
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    • 2004
  • This study was to prepare the anionic liposomes which were to release anticancer drug (doxorubicin) at the hyperthermia temperature $({\sim}42^{\circ}C)$ and to stabilize in bovine serum solution at $37^{\circ}C$. The vesicle size and zeta potential of liposomes in Tris-HCl buffered solution (pH 7.4) were measured by an electrophoretic light scattering spectrophotometer. To estimate the stability of liposomes, liposome size was measured in bovine serum solution at $37^{\circ}C$ for 72 h. The release of doxorubicin from liposome was determined by measuring the fluorescence intensity using fluorescence spectrophotometry with temperature and time. The size of liposomes was from 120 to 160 nm and zeta potential was from $-33.3{\pm}2.4$ to $-75.6{\pm}6.9\;mV$. Anionic liposome was stabilized in bovine serum solution at $37^{\circ}C$ within 72 h. Additionally, the release transition temperature of doxorubicin from liposomes was increased by increasing mole % of anionic phospholipid.

새로운 대기압 플라즈마 소스를 이용한 결정질 실리콘 태양전지 인산 도핑 가능성에 관한 연구 (A Study on Feasibility of the Phosphoric Acid Doping for Solar Cell Using Newly Atmospheric Pressure Plasma Source)

  • 조이현;윤명수;조태훈;권기청
    • 조명전기설비학회논문지
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    • 제27권6호
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    • pp.95-99
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    • 2013
  • Furnace is currently the most important doping process using POCl3 in solar cell. However furnace need an expensive equipment cost and it has to purge a poisonous gas. Moreover, furnace typically difficult appling for selective emitters. In this study, we developed a new atmospheric pressure plasma source, in this procedure, we research the atmospheric pressure plasma doping that dopant is phosphoric acid($H_3PO_4$). Metal tube injected Ar gas was inputted 5 kV of a low frequency(scores of kHz) induced inverter, so plasma discharged at metal tube. We used the P type silicon wafer of solar cell. We regulated phosphoric acid($H_3PO_4$) concentration on 10% and plasma treatment time is 90 s, 150 s, we experiment that plasma current is 70 mA. We check the doping depth that 287 nm at 90 s and 621 nm at 150 s. We analysis and measurement the doping profile by using SIMS(Secondary Ion Mass Spectroscopy). We calculate and grasp the sheet resistance using conventional sheet resistance formula, so there are 240 Ohm/sq at 90 s and 212 Ohm/sq at 150 s. We analysis oxygen and nitrogen profile of concentration compared with furnace to check the doped defect of atmosphere.

Pharmacokinetic Study of Promethazine in Korean Healthy Subjects Using a Validated HPLC Method

  • Jang, Jung-Ok;Go, Eun-Jung;Kim, Na-Hyung;Chung, Soo-Yeon;Park, Hyo-Min;Lee, Hwa-Jeong
    • Biomolecules & Therapeutics
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    • 제13권2호
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    • pp.118-122
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    • 2005
  • The objective of the present investigation was to study pharmacokinetics of promethazine in Korean healthy subjects using a validated HPLC method. The HPLC analysis was performed on a Capcell Pak CN column with a mixture of acetonitrile-0.02M potassium dihydrogen phosphate (42:58, v/v, pH 6.0) and the analyte was quantified with UV detection at 251 nm. The calibration curve of the drug was linear over the range of 1-40ng/mL in human serum and the limit of quantification (LOQ) was 1 ng/mL. This analytical method was validated and shown to be specific, accurate, precise and reproducible. This method was applied to pharmacokinetic study of promethazine in Korean healthy volunteers following an oral administration of two 25 mg Himazin tablets (50 mg promethazine ${\cdot}$HCI) after overnight fasting. Serum samples were collected at given intervals over a 36-hour period (12 points) and pharmacokinetic parameters were determined from serum concentration-time profile using WinNonlin program. The estimated $AUC_{0__\infty}$, $AUC_{0_\infty}$, $C_{max}$, $T_{max}$ and $t_{1/2}$ of promethazine obtained from Korean healthy subjects were 103.84 ${\pm}$84.30 ng${\cdot}$hr/mL, 87.94${\pm}$81.02 ng${\cdot}$hr/mL, 13.43${\pm}$10.92 ng/mL, 2.00${\pm}$1.16 hr and 5.88${\pm}$3.47 hr, respectively.