• Title/Summary/Keyword: indirect method

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Analysis of Microtoxins in the Nakdong River Watershed

  • Park, Jung-Min;Lee, Jae-Jung;Hwang, Dong-Jin;Yang, Sang-Yong
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.11a
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    • pp.99-102
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    • 2003
  • The different methods such as HPLC, indirect- and direct-ELISA were employed for the analysis of microtoxins and the results of each method were compared in terms of the detection limit and accurary. Three toxins, microcystin-RR, -LR and -YR were clearly separated by HPLC using 0.05 M methanol and phosphate buffer used as a solvent system. The calibration curves for the toxins were linear in the range of 5 ng to 50 ng. The standard curves for the immunoassay of microcystin obtained by direct and indirect ELISA are compared. The linear responses of inhibitions of binding by microcystin in the direct and indirect competitive ELISA were in the range of 10 ng to 1000 ng and 50 pg to 160 pg, respectively. Distribution of microtoxins at 11 sites in the Nakdong river and several lakes in Korea was also studied. The most dominant microcystin variant in the test sites was found to be microcystin-RR.

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Analysis of Anions by Indirect Photometric Detection (I) (간접 분광 검출법에 의한 음이온의 분석(I))

  • Park, Man-Ki;Kim, Bak-Kwang;Park, Jeong-Hill;Kim, Kyoung-Ho;Lee, Mi-Yung;Jung, Jae-Eun
    • YAKHAK HOEJI
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    • v.34 no.3
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    • pp.215-218
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    • 1990
  • An ion chromatographic method based on indirect photometric detection of UV transparent anions was developed. Separation of anion was accomplished on strong anion exchange column (Waters SAX) using UV detector at 254 nm. Among examined UV-active additives (Dns-H, Dns-glu, Dnsser, Dns-val), Dns-glu showed the highest sensitivity. Studies on the effects of the pH and ionic strength of eluent revealed that the increase of pH and ionic strength of the eluent decreased capacity factor. The best eluent for the separation of acetate, fluoride, chloride, nitrate and bromide was $1\;{\times}\;10^{-4}M$ Dns-glu in 5 mM phosphate buffer (pH 6.30). The detection limit of chloride ion was 2.1 ng in this condition.

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Papermill Wastewater Treatment by Indirect aerated Sebmerged Biofilter (간접포기식 침지여상에 의한 제지페수처리)

  • 원찬희
    • Journal of Environmental Science International
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    • v.2 no.2
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    • pp.135-144
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    • 1993
  • The purpose of this experimental research was focused to improve the quality of the effluent and the yielded sludge when the papermill wastewater was treated by the indirect aerated submerged biofilter as a second treatment method of papermill wastewater. Changing the various experimental factors (Nutrient additions or not, HRT, Fh ratio, recirculation ratio, etc) with indirect aerated submerged biofilter, the results are as follows. 1) because of the microbes concentration could be sustained to 9, oho man in submerged biofilter and then the volumetric organic loads could be increased to 2.7 kg-BOD/$m^3$<\TEX>/day, the reactor volume can be reduced. 2) Because of the yield coefficient(Y) and the endogenous decay coefficient(kd) were revealed 0.4 and 0.07/d, the yielded sludge volume was reduced. 3) The concentration of the sloughed sludge in the reactor was 2.62~4.01 %, so the thickener could be omited in the papermill wastewater sludge treatment process. 4) When the operating was conducted at HRT of 4hrs, the treatment efficiencies of BOD and COD were obtained 80% and 70%. 5) The range of the theoretical recirculation ratios of this reactor was 14~26. According to those ratios, at the low loads ( BOD volumetric loads is less than 0.79 kg-BOD/$m^3$<\TEX>/day, FM ratio is less than 2.0/d) the results were fitted to the theoretical recirculation ratios (14 ~26) and at the high loads the efficiency were increased to the rise of recirculation ratios.

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Flexural strength of indirect composite resin with different polymerization conditions (중합 조건에 따른 간접복합레진의 굴곡강도)

  • Geum, Young-Hee;Kim, Busob
    • Journal of Technologic Dentistry
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    • v.35 no.4
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    • pp.333-341
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    • 2013
  • Purpose: The purpose of this study was to evaluate the flexural strength of indirect composite resins with different polymerization conditions. Methods: Ten specimens ($2mm{\times}2mm{\times}25mm$) of each composite resins (Tescera (T), Gradia (S) and Sinfony (S)) were fabricated by two polymerization methods : manufacturers's and light heat pressure. Composite resins polymerized by manufacturers's method and light heat pressure served as control (TS, GS and SS) and experimental groups (TE, GE and SE), respectively. The composite resins were tested for flexural strength and the surface of composite resins were observed with scanning electron microscope (SEM) under X1,000 magnification. Results: The flexural strength values of cured composite resin decreased in the following order: TE (195.4MPa), TS (179.8MPa), GE (169.9MPa), SE (137.7MPa), SS (111.1MPa) and GS (100.9MPa) groups. Conclusion: The flexural strength values between the control and the experimental groups were not significantly different although experimental groups showed higher flexural strength values than control groups.

A Study on the Quantity Analysis to the Heat Variation for the Stenosis of the Lumber by the Acupuncture-Moxa Cautery Stimulations (척추관협착증에 있어서 침과 뜸 자극에 의한 체열 변화의 정량적 해석에 관한 연구)

  • Jo, Bongkwan
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.17 no.3
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    • pp.253-262
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    • 2013
  • Objectives This study is on the quantifying method for the acupuncture-moxa cautery heat response index, which are based on the some definitions. Methods The magnitude of the acupuncture-moxa cautery is defined by the pain-feeling of the acupuncture-moxa cautery stimulation: the stimulation magnitude of the acupuncture is 1, that of the direct moxa-cautery is 2, and that of the indirect moxa-cautery is 0.5. The heat variation of the acupuncture-moxa cautery stimulation is defined by the heat variations of the characteristic points pre/post-stimulations in the stenosis of the lumber. The acupuncture-moxa cautery heat response index is defined by the ratio of between the magnitude of the heat variation and the natural logarithmic magnitude of the stimulation. Results With the respect of the acupuncture-moxa cautery heat response index, I experimented and estimated 4 types of stimulations in the stenosis of the lumber: the single acupuncture stimulation with 40%, the single direct moxa-cautery stimulation with 52%, the combinational acupuncture-moxa cautery stimulations with 27%, and the combinational acupuncture-indirect electronic moxa-cautery stimulations with 53%. Conclusions According to the acupuncture-moxa cautery heat response index. the combinational acupuncture-moxa cautery stimulations especially need to be changed to the combinational acupuncture-indirect electronic moxa-cautery stimulations.

A Study on Indirect-Direct Bandgap Structures of 2D-layered Transition Metal Dichalcogenides by Laser Etching (2차원 층상 구조 전이금속 칼코겐화합물의 레이저 식각에 의한 직접-간접 띠간격 구조 연구)

  • Moon, Eun-A;Ko, Pil-Ju
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.9
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    • pp.576-580
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    • 2016
  • Single-layered transition metal dichalcogenides (TMDs) exhibit more interesting physical properties than those of bulk TMDs owing to the indirect to direct bandgap transition occurring due to quantum confinement. In this research, we demonstrate that layer-by-layer laser etching of molybdenum diselenide ($MoSe_2$) flakes could be controlled by varying the parameters employed in laser irradiation (time, intensity, interval, etc.). We observed a dramatic increase in the photoluminescence (PL) intensity (1.54 eV peak) after etching the samples, indicating that the removal of several layers of $MoSe_2$ led to a change from indirect to direct bandgap. The laser-etched $MoSe_2$ exhibited the single $MoSe_2$ Raman vibration modes at ${\sim}239.4cm^{-1}$ and ${\sim}295cm^{-1}$, associated to out-of-plane $A_{1g}$ and in-plane ${E^1}_{2g}$ Raman modes, respectively. These results indicate that controlling the number of $MoSe_2$ layers by laser etching method could be employed for optimizing the performance of nano-electronic devices.

Minimally Invasive Plate Osteosynthesis of Radius-Ulna Fracture using Circular External Fixator in a Dog

  • Kwon, Yong-hwan;Kang, Jin-su;Kim, Young-ung;Cho, Hyoung-sun;Lee, Ki-chang;Kim, Nam-soo;Kim, Min-su
    • Journal of Veterinary Clinics
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    • v.34 no.1
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    • pp.47-49
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    • 2017
  • Fracture stabilization techniques continue to evolve and provide approaches that minimize the iatrogenic trauma associated with surgical procedures. Minimally invasive plate osteosynthesis (MIPO) is a recently described method of biological internal fixation performed by introducing a bone plate via small insertional incisions that are remote to the fracture site. Indirect reduction techniques can generally be utilized when performing MIPO. In this case report, we describe MIPO of a radius-ulna fracture by indirect reduction using circular external fixation for alignment and distraction in a dog.

Combining different forms of statistical energy analysis to predict vibrations in a steel box girder comprising periodic stiffening ribs

  • Luo, Hao;Cao, Zhiyang;Zhang, Xun;Li, Cong;Kong, Derui
    • Steel and Composite Structures
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    • v.45 no.1
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    • pp.119-131
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    • 2022
  • Due to the complexity of the structure and the limits of classical SEA, a combined SEA approach is employed, with angle-dependent SEA in the low- and mid-frequency ranges and advanced SEA (ASEA) considering indirect coupling in the high-frequency range. As an important component of the steel box girder, the dynamic response of an L-junction periodic ribbed plate is calculated first by the combined SEA and validated by the impact hammer test and finite element method (FEM). Results show that the indirect coupling due to the periodicity of stiffened plate is significant at high frequencies and may cause the error to reach 38.4 dB. Hence, the incident bending wave angle cannot be ignored in comparison to classical SEA. The combined SEA is then extended to investigate the vibration properties of the steel box girder. The bending wave transmission study is likewise carried out to gain further physical insight into indirect coupling. By comparison with FEM and classical SEA, this approach yields good accuracy for calculating the dynamic responses of the steel box girder made of periodic ribbed plates in a wide frequency range. Furthermore, the influences of some important parameters are discussed, and suggestions for vibration and noise control are provided.

A Highly Sensitive Indirect Enzyme-Linked Immunosorbent Assay (ELISA) Based on a Monoclonal Antibody Specific to Thermal Stable-Soluble Protein in Pork Fat for the Rapid Detection of Pork Fat Adulterated in Heat-Processed Beef Meatballs

  • Sol-A Kim;Jeong-Eun Lee;Dong-Hyun Kim;Song-min Lee;Hee-Kyeong Yang;Won-Bo Shim
    • Food Science of Animal Resources
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    • v.43 no.6
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    • pp.989-1001
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    • 2023
  • Processed foods containing pork fat tissue to improve flavor and gain economic benefit may cause severe issues for Muslims, Jews, and vegetarians. This study aimed to develop an indirect enzyme-linked immunosorbent assay (iELISA) based on a monoclonal antibody specific to thermal stable-soluble protein in pork fat tissue and apply it to detect pork fat tissue in heat-processed (autoclave, steam, roast, and fry) beef meatballs. To develop a sensitive iELISA, the optimal sample pre-cooking time, coating conditions, primary and secondary dilution time, and various buffer systems were tested. The change in the iELISA sensitivity with different 96-well microtiter microplates was confirmed. The detection limit of iELISA performed with an appropriate microplate was 0.015% (w/w) pork fat in raw and heat-treated beef. No cross-reactions to other meats or fats were shown. These results mean that the iELISA can be used as an analytical method to detect trace amounts of pork fat mixed in beef.

LASER ISDG법으로 관찰한 용접재에서의 피로크랙개구거동

  • 송삼흥;김현;최진호
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.10a
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    • pp.263-268
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    • 2001
  • The constant .DELTA. K fatigue tests are performed in SS41 and its weldment. The LASER ISDG method is used in determination of crack opening ratio. This method is more precise than indirect measurement method, faster and easier than other direct measurement method. And obtained results are followed 1) Crack opening ratio U is proportional to fatigue crack growth rate da/dN at constant .DELTA. K 2) Fatigue crack growth rate da/dN in weldment increases in weld metal and heat affected zone, decreases in base metal as crack grows.