• Title/Summary/Keyword: In Situ Degradation

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Interpretation of Protein Feed Degradation Pattern in Ruminant Using an Omasal Digesta Sampling Technique (제 3위 소화액 채취기법을 이용한 반추위 단백질 사료 분해 패턴 측정법의 고찰)

  • 최창원;백경훈;강수원;이병석;오영균;김경훈
    • Journal of Animal Science and Technology
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    • v.48 no.4
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    • pp.541-554
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    • 2006
  • Present review is to introduce an omasal sampling technique in rumen proteolysis and to consider some information on the omasal sampling technique with particular emphasis on methodological aspects. Use of the omasal sampling technique provides a new opportunity for accurate estimation of rumen metabolism with overcoming limitations of previous in vivo, in vitro and/or in situ methods. The potential advantages of the present technique compared with post-ruminal sampling techniques include following points; 1) only rumen cannulated animals are required, 2) less endogenous nitrogen (N) is contaminated in omasal digesta and 3) omasal digesta are devoid of exposure to acid peptide hydrolysis occurring in the abomasum. Estimates of soluble non-ammonia N (SNAN) in omasal digesta indicate that the assumptions underlying the in situ method that rapidly degradable N fraction can be degraded at an infinite rate and only insoluble dietary N escapes the rumen may be not valid. Quatitatively higher peptide concentration rather than free amino acid and soluble protein in escapable SNAN suggests that hydrolysis of peptide to amino acid may be the rate-limiting step in rumen proteolysis.

Modeling Techniques for Geoenvironmental Engineering Problems

  • Singh, D.N.;Rao, B. Hanumantha
    • Proceedings of the Korean Geotechical Society Conference
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    • 2007.09a
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    • pp.542-557
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    • 2007
  • Contamination of subsurface results in degradation of geomaterials (i.e., soils and rock mass), in the long run. This is mainly due to the presence of chemical and/or radiological materials in undesirable concentrations and at elevated temperatures. However, as contaminant-geomaterial interaction is an extremely slow and complex process, which primarily depends on their physical, chemical and mineralogical properties, it is quite difficult to study this interaction under laboratory or in situ conditions. In such a situation, accelerated physical modeling, using a geotechnical centrifuge, and finite element/difference based numerical modeling techniques are found to be quite useful. This paper presents details of various modeling techniques developed by the researchers at the Indian Institute of Technology Bombay, Mumbai, India, for studying heat migration, flow and interaction (fate) of reactive and non-reactive contaminants in the geoenvironment, under saturated and unsaturated conditions. In addition, paper presents details of the technique that can be employed for determining susceptibility of a material to undergo physico-chemico-mineralogical alterations due to its interaction with contaminants.

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Use of Modern Non­destructive Techniques in High Temperature Degradation of Material and Coatings

  • Lee, C.K.;Sohn, Y.H.
    • International Journal of Korean Welding Society
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    • v.3 no.2
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    • pp.29-39
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    • 2003
  • The durability and reliability of thermal barrier coatings (TBCs) play an important role in the service reliability, availability and maintainability (RAM) of hot­section components in advanced turbine engines for aero and utility applications. Photostimulated luminescence spectroscopy (PSLS) and electrochemical impedance spectroscopy (EIS) are being concurrently developed as complimentary non­destructive evaluation (NDE) techniques for quality control and life­remain assessment of TBCs. This paper overviews the governing principles and applications of the luminescence and the impedance examined in the light of residual stress, phase constituents and resistance (or capacitance) in TBC constituents including the thermally grown oxide (TGO) scale. Results from NDE by PSLS and EIS are discussed and related to the microstructural development during high temperature thermal cycling, examined by using a variety of microscopic techniques including focused ion beam (FIB) in­situ lift­out (INLO), transmission and scanning transmission electron microscopy (TEM and STEM).

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Effects of feeding starch sugar by-products on in situ rumen disappearance rate, growth performance, and carcass characteristics of late finishing Hanwoo steers

  • Choi, Yongjun;Park, Geetae;Kang, Hyokon;Ahn, Jiyeon;Lee, Eunchae;Na, Youngjun;Lee, Sangrak
    • Animal Bioscience
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    • v.35 no.2
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    • pp.217-223
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    • 2022
  • Objective: The aim of this study was to determine the effects of feeding starch sugar byproducts (SSBs) on in situ disappearance rate, performance, and carcass characteristics of Hanwoo steers in the late finishing stage. Methods: To determine the in situ disappearance rate, nylon bags filled with 5 g of SSB were inserted into the ventral sac of two cannulated Holsteins cows and incubated for 0, 2, 4, 8, 16, 24, and 48 h. A total of 30 Hanwoo steers were fed the experimental diets, which were basal diet (control) and 7% SSB on an as-fed basis (4.35% dry matter [DM]), formulated according to requirements of the Korean Feeding Standard for Hanwoo. The experiment was conducted over 80 days using a completely randomized block design. Results: Soluble fraction a of DM and organic matter (OM) was 44.20% and 64.60% DM, fraction b was 23.00% and 19.40% DM, and c values (the rate of degradation of fraction b) were 0.04 and 0.04/h, respectively. The effective degradability of DM at rumen solid outflow rates of 0.02, 0.05, and 0.08/h was 59.83, 54.75, and 52.16, respectively, and for OM was 77.78, 73.52, and 71.34, respectively. Initial and final body weight, average daily gain, DM intake, and gain:feed did not differ significantly between control and SSB groups during the entire experimental period. Carcass traits of Hanwoo steers with SSB supplementation were not significantly different between treatments except for dressing percentage, which was greater with SSB treatment. The content of saturated fatty acid (SFA) was greater and that of unsaturated fatty acids (UFA) was lower in the SSB group than in the control group. The ratio of UFA to SFA was significantly lower in the SSB group than in the control group. Conclusion: A total mixed ration containing less than 4.0% DM of SSBs can be used in Hanwoo steers without a decrease in productivity and carcass traits.

Ultrasonic degradation of polypropylene and its application for the development of PP based copolymer and nanocomposite

  • Ryu, Joung-Gul;Lee, Pil-Soo;Kim, Hyungsu;Lee, Jae-Wook
    • Korea-Australia Rheology Journal
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    • v.13 no.2
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    • pp.61-65
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    • 2001
  • Thermoplastic nanocomposites based on the copolymers of polypropylene (PP)-polystyrene (PS) and organically modified montmorillonite (org-MMT) were produced by using power ultrasonic wave in an intensive mixer. Owing to the unique action of the ultrasonic wave, free radicals of styrene monomers and macroradicals of PP were generated, by which copolymers of PP and PS were formed. Another important aspect of using ultrasonic wave during the mixing process was to enhance nano-scale dispersion of org-MMT by destructing the agglomerates of org-MMT in the polymer matrix. Optimum conditions for the in-situ copolymerization and melt intercalation were studied with various concentrations of styrene monomer, sonication time and different kinds of clay. It was found that a novel attempt carried out in this study yielded further improvement in the mechanical performance of the nanocomposites compared to those produced by the conventional melt mixing process.

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Ellipso-Microscopic Observation of Titanium Surface under UV-Light Irradiation

  • Fushimi, K.;Kurauchi, K.;Nakanishi, T.;Hasegawa, Y.;Ueda, M.;Ohtsuka, T.
    • Corrosion Science and Technology
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    • v.15 no.6
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    • pp.265-270
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    • 2016
  • The ellipso-microscopic observation of a titanium surface undergoing anodization in $0.05mol\;dm^{-3}$ of $H_2SO_4$ was conducted. During irradiation by ultra-violet (UV) light with a wavelength of 325 nm, the titanium surface allowed for the flow of a photo-induced current and showed up as a bright, patch-like image on an ellipso-microscopic view. The brightness and patch-pattern in the image changed with flowing photo-induced current. The changes in the brightness and the image corresponded to the formation and/or degradation of titanium oxide due to the photo-electrochemical reaction of the oxide. An in situ monitoring using the ellipso-microscope revealed that the film change was dependent on the irradiation light power, by UV-light increases the anodic current and results in the initiation of pitting at lower potentials as compared with the non-irradiated condition.

UV-Degradation Chemistry of Oriental Lacquer Coating Containing Hindered Amine Light Stabilizer

  • Hong, Jin Hu;Park, Mi Yeong;Kim, Hyeon Gyeong;Choe, Jeong O
    • Bulletin of the Korean Chemical Society
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    • v.21 no.1
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    • pp.61-64
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    • 2000
  • FT-IR/ATR analysis shows that the oriental lacquer coating network degrades mostly in the unsaturated side chain. The rate of increase in carbonyl intensity (a measure of photodegradation) during the accelerated weathering test was substantially different for the unstabilized and stabilized samples; adding 2 wt% HALS into the oriental lacquer formulation enhanced photostabilization up to three times. Weight loss measurements, another indication of photodegradation, and SEM analysis support this conclusion. Despite the presence of the photo-stabilizer, the other properties of the lacquer were not significantly affected. In particular, the curing behavior of purified lacquer (PL) and HALS-stabilized samples is similar, although the in-situ DETA analysis showed that addition of HALS can slightly retard the cure reaction rate in oriental lacquer coating. It is hypothesized that this cure retardation may be related to the salt formation between HALS and acid of oriental lacquer.

Degradation of TPHs, TCE, PCE, and BTEX Compounds for NAPLs Contaminated Marine Sediments Using In-Situ Air Sparging Combined with Vapor Extraction (증기추출법과 결합된 공기주입법을 이용한 비수용성액체 해양퇴적물의 TPHs, TCE, PCE 및 BTEX 정화)

  • Lee, Jun-Ho;Han, Sun-Hyang;Park, Kap-Song
    • Economic and Environmental Geology
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    • v.46 no.5
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    • pp.425-444
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    • 2013
  • This study was carried out in order to determine the remediation of total petroleum hydrocarbons (TPHs), trichloroethylene (TCE), perchloroethylene (PCE), benzene, toluene, ethylbenzene and xylenes (BTEX) compounds for non-aqueous phase liquids (NAPLs) using in-situ air sparging (IAS) / vapor extraction (VE) with the marine sediments of Mandol, Hajeon, Sangam and Busan, South Korea. Surface sediment of Mandol area had sand characteristics (average particle size, 1.789 ${\Phi}$), and sandy silt characteristics (average particle size, 5.503 ${\Phi}$), respectively. Sangam surface sediment had silt characteristics (average particle size, 5.835 ${\Phi}$). Sediment characteristics before experiment in the Busan area showed clay characteristics (average particle size, 8.528 ${\Phi}$). TPHs level in the B1 column of Mandol, Hajeon, Sangam, and Busan sediments were 2,459, 6,712, 4,348, and 14,279 ppm. B2 (3 L/min) to B5 (5 L/min) columns reduced 99.5% to 100.0% of TCE and 93.2% to 100.0% of PCE. Removal rates of TCE, PCE, and BTEX are closely correlated (0.90-0.99) with particle sizes and organic carbon concentrations. However, TPHs (0.76) and benzene (0.71) showed the poorer but moderate correlations with the same parameters.

Visualization of Candidate Division OP3 Cocci in Limonene-Degrading Methanogenic Cultures

  • Rotaru, Amelia-Elena;Schauer, Regina;Probian, Christina;Mussmann, Marc;Harder, Jens
    • Journal of Microbiology and Biotechnology
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    • v.22 no.4
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    • pp.457-461
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    • 2012
  • Members of candidate division OP3 were detected in 16S rRNA gene clone libraries from methanogenic enrichment cultures that utilized limonene as a carbon and energy source. We developed probes for the visualization of OP3 cells. In situ hybridization experiments with newly designed OP3-specific probes [OP3-565 and Eub-338(VI)] revealed abundant small OP3 cocci attached to larger cells. Syntrophic Deltaproteobacteria, OP3 cells, and methanogens affiliating with Methanoculleus and Methanosaeta formed the limonene-degrading community.

Cyclic Measurement System for Evaluating Organic Light Emitting Diode Devices (유기 발광 다이오드 소자의 성능·수명 평가를 위한 순환 계측 시스템)

  • Park, Il-Hoo;Na, In-Yeob;Joo, Hyeonpil;Kim, Gyu-Tae
    • Journal of the Semiconductor & Display Technology
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    • v.17 no.1
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    • pp.50-53
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    • 2018
  • Cyclic measurement system using relay circuit for organic light emitting diode (OLED) was demonstrated. The OLED characterization such as current-voltage, impedance, and capacitance-voltage is performed in sequence, repetitively and automatically under full control of the personnel computer (PC) without changing the connection of cables. Owing to in situ degradation by cyclic measurement, the time dependence of the data can give good information on the reliability factor of the OLED devices. Therefore, both performance and reliability of the OLEDs can be evaluated, with no manual operation during the entire process.