• 한국유기농업학회지
• /
• 제23권2호
• /
• pp.373-390
• /
• 2015

This study investigated the effect of coated feed using mixed oil on rumen fermentation characteristics. Two experiments were conducted based on materials that were mixed. First, cashew nut and soybean oils were mixed with white mineral oil. And second, different plant extracts were mixed with white mineral oil. At first experiment, inclusion levels of mixed oil on diet (0.03%, 0.1%, 0.5%) were applied as variables. A coated diet was fermented with rumen inoculum according to in vitro rumen fermentation and its parameters were investigated. In the result of first experiment, no negative effects on rumen pH were found. Significantly decreased dry matter digestibility was detected at 0.5% treatment (P<0.05). Total gas productions in control and 0.03% were significantly greater than those of others (P<0.05). Significantly reduced methane productions were found in all treatments compared to the control (P<0.05). Inclusion of mixed oil did not affect on ammonia production. Total volatile fatty acid production was also not influenced by coating with mixed oils. Rumen fermentation parameters were greatly changed according to introduced plant extracts at second experiment. The significantly lowest and greatest ammonia productions were found at treatments with Ixeris dentata and Plantago asiatica, respectively (P<0.05). The significantly greatest acetate and propionate productions were detected at treatments with Crucuma longa and Zizyphus vulgaris 1, respectively (P<0.05). All treatments, except Chrysanthemum idicum, Euyale ferox seed, Moringa leaf and fruit and Zizyphus vulgaris 1, showed significantly increased total volatile fatty acid production compared to the control (P<0.05). Only Paeonia lactiflora showed significantly lesser gas production than the control (P<0.05). In methane production, Ceramium, Zizyphus, Paeonia, Agrimonia, Torilis, Mugwort, Foeniculum, Euphorbia, Taraxacum, Artemisia, Momordica, Curcuma and Moringa reduced methane significantly compared to the control (P<0.05).

• 펄프종이기술
• /
• 제44권4호
• /
• pp.16-24
• /
• 2012

To characterize the coating structure, diverse methods such as mercury intrusion, nitrogen adsorption and oil absorption methods have been developed and widely employed. These indirect techniques, however, have some limitation to explain the actual coating structure. Recently microscopic observation methods have been tried for analyzing structural characteristics of coating layers. Preparation of the undamaged cross section of a coating layer is essential for obtaining high quality image for analysis. In this study, distortion-free cross-section of the coating layer was prepared using a grinding and polishing technique. The coated paper was embedded in epoxy resin and cured. After curing the resin block it was ground with abrasive papers and then polished with diamond particle suspension and nylon cloth. Polished coating layer was sufficient enough to obtain undamaged cross sectional images with scanning electron microscope under backscattered electron image mode. In addition, the SEM images allowed distinction of the coating layer components. Also S/B latex film formed between pigment particles was visualized by osmium tetroxide staining. Pore size distribution and pore orientation were evaluated by image analysis from SEM cross-sectional images.

• Tribology and Lubricants
• /
• 제35권2호
• /
• pp.87-93
• /
• 2019

This work aims to develop a dry lubricant for oilless bush, especially a solid lubricant, thereby creating a coating method with improved properties of anti-friction and load-carrying capacity without oil lubrication. In this work, spherical-shaped powders of thermosetting resin such as polyimide (PI) are mixed with a binder matrix obtained by mixing a fluorocarbon compound resin such as Polytetrafluoroethylene (PTFE) or Ethylene tetra fluoro ethylene (ETFE) with itself or with a non-fluorocarbon thermoplastic resin such as Polyether ether ketone (PEEK). And these dry lubricant mixtures are thickly coated (200-300 mm in the thickness) on the inner surface of the bush by using a wet-typed air-spray deposition method. It was found that the load-carrying capacity of the solid lubricant for excavator bush (60 mm in diameter) that operates under a high load condition (at 40 MPa) is greatly improved owing to the spherical-shaped powders of thermosetting resin. In addition, the coefficient of friction at the sliding surface is also reduced less than 0.1. Thick coating also lowers the contact stress at the edge of a bush that results in better tribological performances. The result suggests that the lubrication performance and durability life of the bush can be remarkably improved even without lubrication (oil or grease).

• 농약과학회지
• /
• 제11권4호
• /
• pp.276-280
• /
• 2007

잎들깨 종자의 파종 밀도 조절을 위해 종자코팅 용도로 사용된 엔도설판 분제에 의한 시설재배지 토양중 endosulfan의 잔류량을 경감시키기 위하여 이를 대체할 수 있는 종자코팅재료의 선발 및 이들이 미치는 발아영향을 조사하였다. 코팅재료는 talc, kaoline, 패화석등 석회류가 가능하였다. 코팅재료의 종자부착을 위한 접착제로는 식용유, 전착제, 알코올, 증류수 순이었으나 종자 발아영향은 반대경향을 나타냈다. 코팅재료별 종자부착성은 패화석, 생석회, 석회, talc, kaoline이 양호하였으나 토양과의 색깔 구별성은 패화석등 석회류에 비해 talc, kaoline이 좋았다. 선발 코팅제를 종자에 부착시 잎들깨의 발아율은 talc, kaoline이 양호하였고 토양과의 색깔 구별성도 양호하였다.

• 한국작물학회지
• /
• 제45권3호
• /
• pp.216-219
• /
• 2000

고지로 개발된 멀칭종이, 여기에 폐식용유를 먹인 밀칭종이 및 요소를 피복한 멀칭종이의 봄감자 멀칭재배에서 잡초발생, 토양온도와 감자의 생육 및 수량 변화를 조사한 결과를 요약하면 다음과 같다. 1 감자 파종 직후 약 10일간의 평균지온(5cm)은 일반 멀칭종이에서 18.9$^{\circ}C$로 무멀칭처리보다 0.5$^{\circ}C$ 낮았고, 기름먹인 멀칭종이의 지온은 20.6$^{\circ}C$로 무멀칭처리보다 1.2$^{\circ}C$높았다. 한편, 밝은 날 최고기온은 무멀칭에 비하여 기름먹인 멀칭종이의 경우는 6.6$^{\circ}C$ 높아졌으며 일반 멀칭종이는 무멀칭에 비하여 4.6$^{\circ}C$ 낮아졌다. 2. 멀칭 후 80일까지 일반 멀칭종이는 약 20% 정도만 분해되었고, 비료를 피복한 멀칭종이의 분해는 이보다 빨랐지만 멀칭 후 80일까지 약 50%정도가 분해되었다. 기름백인 멀종이는 일반 멀칭종이에 비하여 분해가 다소 지연되었다. 모든 멀칭종이 처리에서 감자 전 생육기간에 걸쳐서 잡초의 발생이 효과적으로 억제되었다. 3. 감자의 출아율은 처리간 유의한 차이는 없었으나 기름먹인 종이에서 다른 처리에 비해 다소 낮았으며, 감자의 지상부 및 뿌리건물중도 기름먹인 종이에서 다른 처리에 비해 낮았다. 감자의 수량은 기름먹인 멀칭종이가 다른 처리에 비해 유의하게 낮았으며. 일반 멀칭종이, 요소피복 멀칭종이 및 무멀칭 처리간에는 감자 수량에 유의한 차이가 없었다. 4. 기름먹인 멀칭종이는 출아기 및 생육초기 고온으로 씨감자의 부패가 많았으며 초기생육도 억제되어 수량이 낮았다. 그러나 본 실험(4월15일 파종)에서보다 조기에 파종하는 경우는 본 연구결과와 다를 것으로 생각되며 이에 대해서는 추가적인 검토가 필요하다.

• 유공압시스템학회논문집
• /
• 제1권3호
• /
• pp.7-13
• /
• 2004

The hydraulic pump for a Electro-hydrostatic Actuator for aircrafts should be able to quickly feed large volume of oil into hydraulic cylinder in order to reduce the response time. On the other hand, it should be also able to precisely dispense small amount of oil by low-speed operation so that the steady state position control error of the EHA can be accurately compensated. This paper is focused on the investigation how the plasma coating surface treatment of cylinder barrel with CrSiN can contribute to the reduction of low-speed friction torque of a bent-axis type piston pump. The results showed that the reduction of the friction torque was not remarkable, but that the anti-wear characteristics of the CrSiN-coated cylinder barrel were much better that those of the original one.

• 한국식품과학회지
• /
• 제31권3호
• /
• pp.771-777
• /
• 1999

CSLM 기술을 이용하여 Salmonella enteritidis에 의한 계란 오염 과정을 관찰하여 난막의 3중막 구조, cuticle 층 그리고 5가지 필름 피복의 침투 방어효과를 조사하였다. 난막을 구성하는 fiber의 지름은 각각 outer membrane $1.5{\sim}7.2\;{\mu}m$, inner membrane $0.8{\sim}2.0\;{\mu}m$이었고, limiting membrane을 구성하는 입자의 지름은 $0.1{\sim}1.4\;{\mu}m$이었으며, 두께는 각각 평균 10.0, 3.5, $3.6\;{\mu}m$이었다. 난각과 접해 있는 outer membrane은 다음 층인 inner membrane과 부분적으로 중첩되어있고, limiting membrane의 입자들은 매우 밀집되어 inner membrane과 중첩된 상태로 존재하였다. Cuticle층은 전체 계란 표면적 중 $40{\sim}80%$ 를 덮고 있었으며, 두께는 평균 $6.0\;{\mu}m$이었고 피복 필름들의 평균 두께는 자각 mineral oil $5.0\;{\mu}m$, dextrin $3.6\;{\mu}m$, gelatin $3.9\;{\mu}m$, starch $2.5\;{\mu}m$, chitosan $2.2\;{\mu}m$이었다. 필름 피복에 의한 Salmonella enteritidis 생육 억제효과를 관찰한 결과, chitosan이 가장 효과적이었다. 그리고 trisodium phosphate (TSP), cetylpyridinium chloride (CPC) 처리, 5종의 필름 피복 처리와 무처리한 계란표면에 Salmonella enteritidis를 접종한 후 내부 전이 과정을 CSLM을 이용하여 다색영상화(multi-color imaging)와 시간당 투과 균수에 대한 plate count로 비교한 결과, 난각이나 3중막 구조의 난막보다는 cuticle 층이 Salmonella균의 오염을 차단하는데 결정적인 역할을 하는 것으로 나타났으며, chitosan 피복이 cuticle 층과 비슷한 효과를 보였다. 따라서 피복 필름중에서 chitosan이 최외부 방어막인 cuticle층이 결손된 난각 부위를 피복하는데 가장 적합할 것으로 사료된다.

• 한국축산식품학회지
• /
• 제36권3호
• /
• pp.377-388
• /
• 2016

Objective of the present study is to investigate the effect of coated edible films with chitosan solutions enriched with essential oil (EO) on the chemical, microbial and sensory properties of Kashar cheese during ripening time. Generally, no differences were found in total aerobic mesophilic bacteria, streptococci and lactoccocci counts among cheeses but these microorganism counts increased during 60 and 90 d storage especially in C1 (uncoated sample) as compared with coated samples. Antimicrobial effectiveness of the films against moulds was measured on 30, 60, and 90 d of storage. In addition of fish EO into chitosan edible films samples were showed to affect significantly decreased the moulds (p<0.05) as 1.15 Log CFU/g in C4 (with fish oil (1% w/v) fortified chitosan film) on the 90^th d, while in C1 as 3.89 Log CFU/g on the 90^th d of ripening. Compared to other cheese samples, C2 (coated with chitosan film) and C4 coated cheese samples revealed higher levels of water-soluble nitrogen and ripening index at the end of storage. C2 coated cheese samples were preferred more by the panellists while C4 coated cheese samples received the lowest scores.

• 한국기계가공학회지
• /
• 제19권8호
• /
• pp.110-116
• /
• 2020

Aircraft hydraulic oil reservoirs made with aluminum 7075 have an anodized coating to enable airtightness and corrosion resistance. To maintain a stable oil pressure, the internal surface roughness of the reservoir should be less than approximately 0.2 ㎛. To this end, precision polishing must be performed. However, ensuring the processing quality is challenging, as most polishing operations are performed manually, owing to which, the inner surface roughness is not uniform, and the product quality is irregular. Therefore, we developed a special superfinishing machine to realize the efficient inner polishing of an aircraft hydraulic oil reservoir, by using an abrasive film to improve the process throughput and uniformity. In the experiment involving the superfinishing of an anodized aluminum 7075 cylinder specimen by using the proposed machine, a higher surface roughness than that achieved in the repetitive manual polishing process could be realized.

• Journal of the Korean Wood Science and Technology
• /
• 제49권5호
• /
• pp.471-481
• /
• 2021

This study investigated the hygroscopicity and UV deterioration characteristics of 3 domestic and 4 imported woods using natural oil, stain, and varnish paints. In terms of hygroscopicity, it was found that the hygroscopicity of the painted wood was lower than that of the unpainted wood, and that as the number of coatings increased, the hygroscopicity decreased. In terms of anti-absorption, oil-based chemical paints showed higher resistance than water-based paints, and natural oils showed results comparable to oil-based paints. As for the UV deterioration, the amount of color change of the painted wood was lower than that of the unpainted wood, and there was no significant difference according to the number of times of painting. The amount of color change was found to be low in oil-based paints and hardwoods. Through this study, we confirmed effective moisture blocking and small color changes during painting using paints, and it is believed that wood can be protected from internal and external defects through selective and efficient painting based on data for excellent painting performance.