• Corrosion Science and Technology
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• 제4권3호
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• pp.114-119
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• 2005

Since the degradation caused by corrosion is restricted to the surface of materials, conventional ultrasonic nondestructive evaluation methods based on ultrasonic bulk waves are not applicable to characterization of the corrosion degradation. To take care of this difficulty, a new nondestructive evaluation method that uses ultrasonic backward radiation has been proposed recently. This paper explores the potential of this newly developed method for nondestructive characterization and in-situ monitoring of corrosion degradation. Specifically, backward radiated ultrasounds from aged thermo-mechanically controlled process (TMCP) steel specimens by corrosion fatigue were measured and their characteristics were correlated to those of the aged specimens. The excellent correlation observed in the present study demonstrates the high potential of the backward radiated ultrasound as an effective tool for nondestructive characterization of corrosion degradation. In addition, the potential of the backward radiated ultrasound to in-situ monitoring of corrosion degradation is under current investigation.

• Geomechanics and Engineering
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• 제21권6호
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• pp.527-536
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• 2020

An elastic-plastic solution for cavity expansion problem considering strength degradation, undrained condition and initial anisotropic in-situ stress is established based on the Tresca yield criterion and cavity expansion theory. Assumptions of large-strain for plastic region and small-strain for elastic region are adopted, respectively. The initial in-situ stress state of natural soil mass may be anisotropic caused by consolidation history, and the strength degradation of soil mass is caused by structural damage of soil mass in the process of loading analysis (cavity expansion process). Finally, the published solutions are conducted to verify the suitability of this elastic-plastic solution, and the parametric studies are investigated in order to the significance of this study for in-situ soil test.

• Asian-Australasian Journal of Animal Sciences
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• 제13권8호
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• pp.1076-1083
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• 2000

The aim of this study was to evaluate the effect of Aspergillus oryzae fermentation extract (AFE) on in situ degradation of the various concentrates, forages and by-products in Taiwan. The in situ trial was conducted to determine the effect of AFE on the rate of ruminal degradation of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) of the various local available feedstuff commonly used for dairy cattle. Two ruminal fistulated cows were arranged into a two by two switchback trial. Two dietary treatments were control without AFE inclusion diet and diet with 3 g of AFE (Amaferm) added daily into the total mixed ration (TMR). Results showed that effect of AFE inclusion on the ruminal degradability of concentrates vary; soybean meal is the most responsive feedstuff, corn is the next, whereas full-fat soybean did not response the AFE inclusion at all. The inclusion of AFE significantly depressed most of the nutrient degradation of the concentrates of soybean meal in the first 12-hour in situ incubation. The effect declined in the next 12 hours. Rapeseed meal showed a different trend of response: addition of AFE improved its NDF degradation. The inclusions of AFE significantly improved ADF degradation of roughage after 24 or 48 hours of incubation. However, corn silage and peanut-vines showed a different trend. Effects of AFE inclusion on the by-products degradability were inconsistent. Most of nutrients in rice distillers grain and some in beancurd pomace did show increased degradation by the AFE inclusion.

• Journal of Animal Science and Technology
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• 제49권3호
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• pp.351-358
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• 2007

본 연구는 국내에서 사용되고 있는 몇 가지 단백질 원료사료를 사용하여 단백질 fraction과 in situ 단백질 분해율을 구한 다음 이들 사이에서의 상관관계를 살펴보고자 실시하였다. 원료사료는 대두박, 콘글루텐, 면실박, 카폭박 및 임자박이었다. 단백질 fraction은 CNCPS에서 제시하는 방법으로 구하였으며, in situ 단백질 분해율은 캐뉼라가 장착된 홀스타인 거세우 3두를 이용하여 반추위에서 원료사료를 4, 8, 12 및 24시간 배양하여 구하였다. 단백질 fraction 중 A fraction은 카폭박이 14.6%로 가장 높았고, 콘글루텐이 0.6%로 가장 낮았다(P<0.05). B1 fraction은 대두박이 8.27%로 가장 높았으며, B2 fraction은 대두박과 면실박이 74%로 가장 높았다. B3 fraction은 임자박이 40%로 다른 원료사료에 비교해 뚜렷하게 높았다. C fraction은 콘글루텐이 약 42.5%로 가장 높았다. In situ 조단백질 분해율은 대두박이 98%로 가장 높았고, 콘글루텐은 28%로 가장 낮았다. 단백질 fraction과 in situ 분해율 사이의 상관관계를 보면, 쉽게 용해되는 부분(A, B1 fraction vs a값) 사이에, in situ 조단백질 분해율과 소화가능한 단백질 fraction 사이에, 그리고 in situ 조단백질 분해율에서 a값을 제외한 값과 B2+B3 fraction 사이에는 상관관계가 높았다(P<0.01). 본 연구결과에 의하면, 단백질 fraction은 원료사료의 반추위내 분해율을 추정하는 데 이용될 수 있을 것으로 사료되며, 앞으로 더 정확한 평가를 위해서는 더 많은 원료사료에 대한 분석이 필요하다고 본다.

• 전자공학회논문지A
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• 제31A권6호
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• pp.107-116
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• 1994

In this paper, The electrical properties of MOS capacitors and transistoras with gate of in-situ doped amorphous Si and poly Si doped by POCI$_3$. Under constant current F-N stress, MOS capacitors with in-situ doped amorphous Si gate have shown the best resistance to degradation in reliabilty properties such as increase of leakage current, shift of gate voltage (V$_{g}$). shift of flat band voltage (V$_{fb}$) and charge to breakdown(Q$_{bd}$). Also, MOSFETs with in-situ doped amorphous Si gate have shown to have less degradation in transistor properties such as threshold voltage, transconductance and drain current. These improvements observed in MOS devices with in-situ doped amorphous Si gate is attributed to less local thinning spots at the gate/SiO$_2$ interface, caused by the large grain size and the smoothness of the surface at the gate/SiO$_2$ interface.

• Structural Engineering and Mechanics
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• 제52권4호
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• pp.701-721
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• 2014

In the assessment of existing RC buildings, the reliable appraisal of the compressive strength of in-situ concrete is a fundamental step. Unfortunately, the data that can be obtained by the available testing methods are typically affected by a high level of uncertainty. Moreover, in order to derive indications about the degradation and ageing of the materials by on site tests, it is necessary to have the proper terms of comparison, that is to say, to know the reference data measured during the construction phases, that are often unavailable when the building is old. In the cases when such a comparison can be done, the in situ strength values typically turn out to be lower than the reference strength values (tests performed on taken samples during the construction). At this point, it is crucial to discern and quantify the specific effect induced by different factors: ageing of the materials; poor quality of the placement, consolidation or cure of the concrete during the construction phases; damage due to drilling. This paper presents a procedure for correlating the destructive compressive tests and non-destructive tests (ultrasonic pulse velocity tests) with the data documenting the compressive strength tested during the construction phases. The research work is aimed at identifying the factors that induce the difference between the in-situ strength and cubes taken from the concrete casting, and providing, so, useful information for the assessment procedure of the building.

• Asian-Australasian Journal of Animal Sciences
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• 제13권7호
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• pp.906-912
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• 2000

The effect of ammonia treatment and rice bran supplementation on the in situ rumen degradation of rice straw was determined using three Japanese Corriedale wethers fitted with permanent rumen cannula. About 4 g samples of diets containing 100% untreated rice straw (URS); 100% ammonia treated rice straw (ARS); 65% URS+30% rice bran (RB)+5% soybean meal (SBM) (T1); and 85% ARS+15% RB (T2) were incubated at 0, 4, 8, 16, 24, 48, 72, and 96 hours in the rumen of sheep to measure dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) degradability. The DM disappearance of ARS based diets were about 20% higher than that of URS based diets. Rice bran supplementation improved DM disappearance of URS but not on ammoniated straw. Degradation parameters showed that ammoniation increased rate (c) of straw degradation resulting to higher DM and fiber degradability but RB supplementation did not. ARS gave similar DM and CP solubility and effective rumen degradability (ED) with that of the supplemented groups indicating that ammoniation alone can give the same effect on rumen degradability of sheep receiving low quality roughage. All degradation parameters for NDF were consistently higher in ARS based-diets indicating improved fiber solubility. Rice bran supplementation did not affect degradation characteristics of the diets except on soluble DM and CP fraction (A) of URS but not on ARS.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.389-393
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• 2003

Present study investigate the effect of enzyme supplementation, methods (applied to rumen or enzyme treated diet) compared with no enzyme diet, on rumen fermentation and apparent nutrient digestibility in a $3{\times}3$ Latin square design with three rumen cannulated Korean Native goats. In situ rumen degradation kinetics was studied in three rumen cannulated Holstein steers. Three diets were, no enzyme, 1% enzyme in rumen and 1% enzyme in diet. The enzyme was sprayed onto forage, and the forage: concentrate ratio was 30:70. Degradation kinetics was studied with three enzyme levels (0, 1 and 2%, w/w) and four pre-treatment times (0, 1, 12 and 24 h). Results suggested that enzyme application method did not affect rumen fermentation, ruminal enzyme activity and total tract apparent digestibility. Nutrient degradation rate and effective degradability of DM, NDF and ADF increased with increasing enzyme level and pre-treatment times. Degradation of nutrients was affected by enzymes levels or pre-treatment times. Therefore, it is probable that the improved degradation may be due to the supplemented exogenous hydrolytic enzymes under a certain condition.

• Membrane and Water Treatment
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• 제13권2호
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• pp.97-104
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• 2022

With a small particle size, specific surface area and chemical nature, Pd/Cu-Fe nanocomposites can efficiently remove the organic compounds. In order to understand the applicability for in situ remediation of contaminated groundwater, the degradation of p-nitrophenol by Pd/Cu-Fe nanoparticles was investigated. The degradation results demonstrated that these nanoparticles could effectively degrade p-nitrophenol and near 90% of degradation efficiency was achieved by Pd/Cu-Fe nanocomposites for 120 min treatment. The efficiency of degradation increased significantly when the Pd content increased from 0.05 wt.% and 0.10 wt.% to 0.20 wt.%. Meanwhile, the removal percentage of p-nitrophenol increased from 75.4% and 81.7% to 89.2% within 120 min. Studies on the kinetics of p-nitrophenol that reacts with Pd/Cu-Fe nanocomposites implied that their behaviors followed the pseudo-first-order kinetics. Furthermore, the batch experiment data suggested that some factors, including Pd/Cu-Fe availability, temperature, pH, different ions (SO42-, PO43-, NO3-) and humic acid content in water, also have significant impacts on p-nitrophenol degradation efficiency. The recyclability of the material was evaluated. The results showed that the Pd/Cu-Fe nanoparticles have good recycle performance, and after three cycles, the removal rate of p-nitrophenol is still more than 83%.

• Asian-Australasian Journal of Animal Sciences
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• 제19권8호
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• pp.1120-1126
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• 2006

Dry matter (DM) degradation of leaves from Quercus cercis, Quercus libari, Quercus branti, and Quercus coccifera was determined using two different techniques: (i) in vitro gas production and (ii) the nylon bag degradability technique. In vitro gas production in the presence or absence of PEG and in situ DM disappearance were measured at 3, 6, 12, 24, 48, 72 and 96 h. In situ and in vitro DM degradation kinetics were described using the equation y = a+b ($1-e^{-ct}$). At all incubation times leaves from Quercus branti incubated with or without PEG gave significantly higher gas production than the other oak leaves except for 3 and 6 h incubation when leaves from Quercus branti without PEG supplementation only gave higher gas production than Quercus cercis and Quercus coccifera. At all incubation times except at 3, 6 and 12 h the DM disappearance from Quercus branti was significantly higher than the other species. Generally, PEG supplementation considerably increased the gas production at all incubation times and estimated parameters such as gas production rate ($c_{gas}$), gas production (ml) from the quickly soluble fraction ($a_{gas}$), gas production (b) from the insoluble fraction, potential gas production (a+b). However, all oak leaves did not give the same response to the PEG supplementation. Although the increase in gas production at 96 h incubation time was 8.9 ml for Quercus libari the increase was 5.5 ml for Quercus coccifera. It was concluded that except at early incubation times the relationships between the two methodologies seem to be sufficiently strong to predict degradability parameters from gas production parameters obtained in the presence or absence of PEG.