• Title/Summary/Keyword: In Situ Degradation

Search Result 231, Processing Time 0.025 seconds

The Effect of Single and Mixed Microbial Inoculation on the in situ Fiber Digestibility and Silage of Rice Straw Contaminated Mycotoxins (단일 및 복합 미생물 접종이 곰팡이독소 오염 볏짚의 사일리지 및 In situ 섬유소 소화율에 미치는 영향)

  • Ha Guyn Sung
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.42 no.4
    • /
    • pp.229-236
    • /
    • 2022
  • This study was conducted to evaluate the efficacy of adding the microbial inoculants to silage for reducing mycotoxins in rice straw silage. When a single agent of L. plantarum and a mixed agent of L. plantarum and S. cerevisiae were added in rice straw silage contaminated mycotoxins, it had an effect on silage fermentation and fiber degradation as well as mycotoxin reduction. Among the mycotoxins, only ochratoxin A and zearalenone were found in the test sample. Ochratoxin A and zearalenone showed a decreasing trend with the addition of silage inoculants compared to the control groups (38.11±2.22 and 633.67±50.30 ㎍/kg), and there was a significant difference at the mixed agents; 27.78±2.28 and 392.72±25.04 ㎍/kg, respectively (p<0.05). The pH was lower in the single agent and the mixed agent compared to the control (p<0.05). The concentration of lactic acid was higher in the single agent (11.73±0.31 mM) than in the control group (8.18±0.93 mM), and the highest concentration was 16.01±0.88 mM in the mixed agent (p<0.05). Acetic acid and propionic acid were found to be significantly lowered with the addition of silage inoculants (p<0.05). Total VFA was also lower at the addition of silage inoculants than the control group (p<0.05). The rumen in situ dry matter degradation of NDF and ADF was maintained at the highest levels of the mixed agent during the culture period, followed by the single agent and the control group at the lowest level. NDF and ADF degradation showed a significant difference at all time points after 12 and 24 hours of culture, respectively (p<0.05). The study results showed that the silage inoculants had the positive effects on quality increasing of rice straw silage; fermentative charateristics, fiber degradation and mycotoxins reduction. Ochratoxin A and zearalenone were greater reduction by adding bacterial inoculants of silage. Therefore it is considered that L. plantarum and S. cerevisiae will improve the quality and stability with remediation of mycotoxin in silage.

Variation and Correlation of Shearing Force with Feed Nutritional Characteristics of Wheat Straw

  • Cui, X.M.;Yang, Z.B.;Yang, W.R.;Jiang, S.Z.;Zhang, G.G.;Liu, L.;Wu, B.R.;Wang, Z.F.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.26 no.10
    • /
    • pp.1466-1473
    • /
    • 2013
  • This experiment was conducted to study the variation laws and correlations of shearing force and feed characteristics including morphological characteristic, chemical composition and in situ degradability of wheat straw. Feasibility of evaluating the nutritional value of wheat straws with shearing force values was analyzed in this study. Six hundred wheat straw plants (Jimai 22) were randomly selected and placed in a cool and ventilated place. Samples were collected in the 1st, 15th, 30th, 45th, 60th d after harvest to measure shearing force, morphological characteristic, nutritional composition. Rumen degradation of dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of wheat straws were determined by the nylon bags method. The results demonstrated that linear and quadratic effects of storage time on all the tested morphological characteristics were significantly correlative (p<0.01). As storage time goes on, all the tested nutrients and their rumen degradations of wheat straw was linearly (p<0.01) and quadratic (p<0.01) correlative except ADF content and rumen degradation of ADF. Significant correlations were determined in linear effect of shearing force on morphological characteristics (p<0.01), and linear density and diameter were a more sensitive predictor than stem thickness for shearing force. There were strong correlations between storage time and all the measured physical characteristics (shearing force, morphological characteristics and shearing force standardized by morphological characteristics) (p<0.01). Nutrition compositions were linearly correlative with shearing force and standardized shearing force (p<0.01). The linear correlation between rumen degradation of DM and NDF and shearing force and standardized shearing force were evident (p<0.01). In conclusion, shearing force, nutrition compositions and their rumen degradation of wheat straw were still dynamic with storage time after harvest. Correlation could be found between shearing force and nutritional characteristics of wheat straw. Nutrient content, morphological index and rumen degradation of DM and NDF could be predicted by changes in shearing force. Shearing force should be applied according to a standardized storage time when it is used to forecast the feed value of wheat straws.

Kinetics of In-situ Degradation of Nerve Agent Simulants and Sarin on Carbon with and without Impregnants

  • Saxena, Amit;Sharma, Abha;Singh, Beer;Suryanarayana, Malladi Venkata Satya;Mahato, Timir Haran;Sharma, Mamta;Semwal, Rajendra Prasad;Gupta, Arvind Kumar;Sekhar, Krishnamurthy
    • Carbon letters
    • /
    • v.6 no.3
    • /
    • pp.158-165
    • /
    • 2005
  • Room temperature kinetics of degradation of nerve agent simulants and sarin, an actual nerve agent at the surface of different carbon based adsorbent materials such as active carbon grade 80 CTC, modified whetlerite containing 2.0 and 4.0 % NaOH, active carbon with 4.0 % NaOH, active carbon with 10.0 % Cu (II) ethylenediamine and active carbon with 10.0 % Cu (II) 1,1,1,5,5,5-hexafluoroacetylacetonate were studied. The used adsorbent materials were characterized for surface area and micropore volume by $N_2$ BET. For degradation studies solution of simulants of nerve agent such as dimethyl methylphosphonate (DMMP), diethyl chlorophosphate (DEClP), diethyl cyanophosphate (DECnP) and nerve agent, i.e., sarin in chloroform were prepared and used for the uniform adsorption on the adsorbent systems using their incipient volume at room temperature. Degradation kinetics was monitored by GC/FID and was found to be following pseudo first order reaction. Kinetics parameters such as rate constant and half life were calculated. Half life of degradation with modified whetlerite (MWh/NaOH) system having 4.0 % NaOH was found to be 1.5, 7.9, 1206 and 20 minutes for DECnP, DEClP, DMMP and sarin respectively. MWh/NaOH system showed maximum degradation of simulants of nerve agents and sarin to their hydrolysis products. The reaction products were characterized using NMR technique. MWh/NaOH adsorbent was also found to be active against sulphur mustard.

  • PDF

Tubular Type Direct Methanol Fuel Cell for in situ NMR Diagnosis (In Situ NMR 진단용 원통형 직접 메탄올 연료전지)

  • Joh, Han-Ik;Um, Myung-Sup;Han, Kee-Sung;Han, Oc-Hee;Ha, Heung-Yong;Kim, Soo-Kil
    • Journal of the Korean Electrochemical Society
    • /
    • v.12 no.4
    • /
    • pp.329-334
    • /
    • 2009
  • This study is to develop a fuel cell system applicable to an in situ NMR (Nuclear magnetic resonance) diagnosis. The in situ NMR can be used in real time monitoring of various reactions occurring in the fuel cell, such as oxidation of fuel, reduction of oxygen, transport phenomena, and component degradation. The fuel cell for this purpose is, however, to be operated in a specifically designed tubular shape toroid cavity detector (TCD), which constrains the fuel cell to have a tubular shape. This may cause difficulties in effective mass transport of reactants/products and uniform distribution of assembly pressure. Therefore, a new flow field designed in a particular way is necessary to enhance the mass transport in the tubular fuel cell. In this study, a tubular-shaped close-type flow field made of non-magnetic material is developed. With this flow field, oxygen is effectively delivered to the cathode surface and the produced water is readily removed from the membrane-electrode assembly to prevent flooding. The resulting DMFC (direct methanol fuel cell) outperforms the open-type flow field and exhibits $36\;mW/cm^2$ even at room temperature.

STUDIES IN FIBRE DIGESTION AND PASSAGE RATE OF LIQUID AND SOLID IN CATTLE AND BUFFALOES

  • Abdullah, N.;Ho, Y.W.;Mahyuddin, M.;Jalaludin, S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.4 no.2
    • /
    • pp.137-141
    • /
    • 1991
  • Rumen liquor characteristics and disappearance rate of dry matter were studied in Kedah-Kelantan cattle and swamp buffaloes fed grass of rice straw-based diet. Cobalt-EDTA and chromium mordented fibres prepared from the faecal material were used to determine the liquid and solid particles movement in both animal species fed with rice straw. Swamp buffaloes showed a more intense rumen fermentation activity than Kedah-Kelantan cattle when both species were fed straw-based diet. The buffaloes also demonstrated faster rates of grass and straw degradation in situ. The fluid outflow rate from the rumen of buffalo ($1.06{\pm}0.19l/h$) was observed to be slower than that of cattle ($1.55{\pm}0.01l/h$). No significant differences between cattle and buffaloes were observed in rumen fluid volume and passage rate of small particles from the rumen.

Evaluation of Transformation Capacity for Degradation of Ethylene Chlorides by Methylosinus trichosporium OB3b

  • Lee, Eun-Yeol;Kang, Jung-Mee;Park, Sung-Hoon
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.8 no.5
    • /
    • pp.309-312
    • /
    • 2003
  • The transformation capacity (T$\_$c/) of Methylosinus trichosporium OB3b in the degradation of ethylene chlorides was determined by measuring the decrease of soluble methane monooxygenase (sMMO) activity of resting cells in batch experiments. All measurements of sMMO activity were taken in the presence of 20 mM formate to avoid the deficiency of reducing power, and within 2 hrs to avoid the effect of natural inactivation from instability of the resting cells. The constant T$\_$c/ values of 0.58 ${\pm}$ 0.132 and 0.80 ${\pm}$ 0.17 ${\mu}$mol/mg cell were obtained for trichloroethylene (TCE) and 1,2-dichloroethylene (cis and trans-1,2-DCE), respectively, regardless of their concentrations. The transformation capacity measured by this method can be used to predict the amount of cells that should be stimulated in in-situ bioremediation.

Implementation of Stretched-Exponential Time Dependence of Threshold Voltage Shift in SPICE (Stretched-Exponential 형태의 문턱전압 이동 모델의 SPICE구현)

  • Jung, Taeho
    • Journal of the Semiconductor & Display Technology
    • /
    • v.19 no.1
    • /
    • pp.61-66
    • /
    • 2020
  • Threshold voltage shift occurring during operation is implemented in a SPICE simulation tool. Among the shift models the stretched-exponential function model, which is frequently observed from both single-crystal silicon and thin-film transistors regardless of the nature of causes, is selected, adapted to transient simulation, and added to BSIM4 developed by BSIM Research Group at the University of California, Berkeley. The adaptation method used in this research is to select degradation and recovery models based on the comparison between the gate and threshold voltages. The threshold voltage shift is extracted from SPICE transient simulation and shows the stretched-exponential time dependence for both degradation and recovery situations. The implementation method developed in this research is not limited to the stretched-exponential function model and BSIM model. The proposed method enables to perform transient simulation with threshold voltage shift in situ and will help to verify the reliability of a circuit.

Health Monitoring of a Composite Actuator with a PZT Ceramic during Electromechanical Fatigue Loading

  • Woo, Sung-Choong;Goo, Nam-Seo
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.27 no.6
    • /
    • pp.541-549
    • /
    • 2007
  • This work describes an investigation into the feasibility of using an acoustic emission (AE) technique to evaluate the integrity of a composite actuator with a PZT ceramic under electromechanical cyclic loading. AE characteristics have been analyzed in terms of the behavior of the AE count rate and signal waveform in association with the performance degradation of the composite actuator during the cyclic tests. The results showed that the fatigue cracking of the composite actuator with a PZT ceramic occurred only in the PZT ceramic layer, and that the performance degradation caused by the fatigue damage varied immensely depending on the existence of a protecting composite bottom layer. We confirmed the correlations between the fatigue damage mechanisms and AE signal types for the actuators that exhibited multiple modes of fatigue damage; transgranular micro damage, intergranular fatigue cracking, and breakdown by a short circuiting were related to a burst type signal showing a shortly rising and slowly decaying waveform with a comparably low voltage, a continuous type signal showing a gradual rising and slowly decaying waveform with a very high voltage and a burst and continuous type signal with a high voltage, respectively. Results from the present work showed that the evolution of fatigue damage in the composite actuator with a PZT ceramic can be nondestructively identified via in situ AE monitoring and microscopic observations.

Reliability Improvement of Thin Oxide by Double Deposition of Silicon (실리콘의 이중증착에 의한 산화막 신뢰성 향상)

  • 박진성;양권승
    • Journal of the Korean Ceramic Society
    • /
    • v.31 no.1
    • /
    • pp.74-78
    • /
    • 1994
  • Degradation of thin oxide by doped poly-Si and its improvement were studied. The gate oxide can be degraded by phosphorous in poly-Si doped POCl3. The degradation is increased with the decrement of sheet resistance and poly-Si thickness. Oxide failures of amorphous-Si are higher than those of poly-Si. In-situ double deposition of amorphous-Si, 54$0^{\circ}C$/30 nm, and poly-Si, 6$25^{\circ}C$/220 nm, forms the mismatch structure of grain boundary between amorphous-Si and poly-Si, and suppresses the excess phosphorous on oxide surface by the mismatch structure. The control of phosphorous through grain boundary improves the oxide reliability.

  • PDF

고전류 스트레싱하에서 의 ACF플립칩의 신뢰성 해석에 관한 연구

  • 권운성;백경욱
    • Proceedings of the International Microelectronics And Packaging Society Conference
    • /
    • 2002.05a
    • /
    • pp.247-251
    • /
    • 2002
  • In this paper the maximum current carrying capability of ACAs flip chip joint is investigated based on two failure mechanisms: (1) degradation of the interface between gold stud bumps and aluminum pads; and (2) ACA swelling between chips and substrates under high current stress. For the determination of the maximum allowable current, bias stressing was applied to ACAs flip chip joint. The current level at which current carrying capability is saturated is defined as the maximum allowable current. The degradation mechanism under high current stress was studied by in-situ monitoring of gold stud bump-aluminum pad ACA contact resistance and also ACA junction temperature at various current level. The cumulative failure distributions were used to predict the lifetime of ACAs flip chip joint under high current stressing. These experimental results can be used to better understand and to improve the current carrying capability of ACA flip chip joint.

  • PDF