검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 13

        1.
        2017.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We studied the basic properties and fabrication of reduced graphene oxide (rGO) prepared using eco-friendly reduction agents in the graphene solution process. Hydrazine is generally used to reduce graphene oxide (GO), which results in polluting emissions as well as fixed nitrogen functional groups on different defects in the graphene sheets. To replace hydrazine, we developed eco-friendly reduction agents with similar or better reducing properties, and selected of them for further analysis. In this study, GO layers were produced from graphite flakes using a modified Hummer’s method, and rGO layers were reduced using hydrazine hydrate, L-ascorbic acid, and gluconic acid. We measured the particle sizes and the dispersion stabilities in the rGO dispersed solvents for the three agents and analyzed the structural, electrical, and optical properties of the rGO films. The results showed that the degree of reduction was in the order L-ascorbic acid ≥ hydrazine > glucose. GO reduced using L-ascorbic acid had a sheet resistance of 121 kΩ/sq, while that reduced using gluconic acid showed worse electrical properties than the other two reduction agents. Therefore, L-ascorbic acid is the most suitable eco-friendly reduction agent that can be substituted for hydrazine.
        4,000원
        2.
        2013.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Flexible transparent conducting films (TCFs) were fabricated by dip-coating single-wall carbon nanotubes (SWCNTs) onto a flexible polyethylene terephthalate (PET) film. The amount of coated SWCNTs was controlled simply by dipping number. Because the performance of SWCNT-based TCFs is influenced by both electrical conductance and optical transmittance, we evaluated the film performance by introducing a film property factor using both the number of interconnected SWCNT bundles at intersection points, and the coverage of SWCNTs on the PET substrate, in field emission scanning electron microscopic images. The microscopic film property factor was in an excellent agreement with the macroscopic one determined from electrical conductance and optical transmittance measurements, especially for a small number of dippings. Therefore, the most crucial factor governing the performance of the SWCNT-based TCFs is a SWCNT-network structure with a large number of intersection points for a minimum amount of deposited SWCNTs.
        3,000원
        3.
        2013.03 구독 인증기관 무료, 개인회원 유료
        Artificial insemination (AI) has been performed widely in swine industry using fresh liquid sperm instead of frozen type of sperm. However fresh sperm are not able to preserve more than three days with optimal motility and other sperm parameters for the successful fertilization, since in vitro stored sperm has an oxidative stress that resulted increase of abnormality and acrosome reation. To overcome these major problems, novel preservative formulation is needed to neutralize the oxidative stress and to provide suitable physiological environment for sperm in in vitro. In this study, naturally derived substances such as Poncirus trifoliate (Trifoliate orange), Garcinia mangostana (Mangosteen), pig placenta and testis extracts were tested as sperm preservative agents. Placenta extracts (PE), trifoliate orange extracts (TOE), testes extracts (TE) and mangosteen extracts (ME) were applied to analyze specific parameters for sperm motion characteristics individually and combinatorial. Each individual extract treatment can accelerate the sperm motility but noticeably TOE, TE and ME treatments exhibited the considerable and significant preservation of sperm motility. PE, TE and ME showed a significant (p<0.05) increase in ALH after one week. Further we evaluated the five different combinations of these extracts on sperm motility and its motion characteristics. Surprisingly even after one week ME, TOE and TE combination significantly preserved the sperm motility about 75%. It is noteworthy that unlike individual extract treatment, combination of ME, TOE and TE simultaneously protect the sperm motility and its motion characteristics. Taken together these data conclude that addition of ME, TOE and TE can be effective for preservation of pig sperm.
        4,000원
        4.
        2017.05 서비스 종료(열람 제한)
        Background : This study aimed to determine the use of proper organic fertilizer through side dressing application in the environmental cultivation of Adenophora triphylla var. japonica Hara. to improve farming income. Methods and Results : In the cultivation of eco-friendly and environmental medicinal plant like Adenophora triphylla var. japonica Hara., it is necessary to use organic instead of chemical fertilizer. Organic fertilizers such as HL, CK, OK were applied three (3) times during the last ten days of July, August, and September. There was no significant difference between CF and NT, in terms of the number of rooting per 1㎡ which was 12.1 -12.9. There were also no significant differences in plant length, leaf length, leaf width and dry weight. The root length was 19.9 ㎝, which was the longest in CK, and 16.8 ㎝, the shortest in ST, but described as no significant difference. The root width was 14.8 – 5.5 ㎜, and the number of rootlet was 5.7 - 7.1, but was considered not a significant difference. The dry weight was 16.6 g in HL, 16.3 g in CK and ST, and 15.6 g in OK, but still there were no significant differences observed. However, it was 14.6 g in NT, which was considered the lowest, thus there was a significant difference. The number of dry root per 10 a was 149 ㎏ which is considered the most in HL, 141 ㎏ in CK, 140 ㎏ in ST, and 138kg in OK yet there were no significant differences observed. While NT only had 123 ㎏ hence, there was a significant difference on the number of dry root per 10a as compared with the group applied with the three organic fertilizers. Conclusion : In conclusion, it is proper to use Organic Fertilizer HL and CK through side dressing application in growing Adenophora triphylla var. japonica Hara.
        5.
        2017.05 서비스 종료(열람 제한)
        Background : This project was conducted to determine proper seed harvest time and seed storage methods of Adenophora triphylla var. japonica Hara. Methods and Results : When Adenophora triphylla var. japonica Hara. transplanted this year, seeding can only be done the following year. Therefore, the seeds harvested in the interval of ten (10) days were investigated for seed harvest amount, germination rate, seed storage temperature and storing on container, between the period late August and mid-October. It is when the seed fructification started and ended. The seeds harvested from the first ten (10) days of October to mid October were 87.9% in whole seeds. The proper seed harvesting time was mid October which has a germination rate of 75% in whole seed harvest time. The lowest germination rate of 27.3% was at the germination temperature of 15℃. As the temperature rises, the germination rate increases. In 29℃, the germination rate was at 79% which is the highest; and from 30℃, the germination rate decreased to 71%. When the storage temperature was at 0℃ after storage of 5 months, the germination rate was at 83%. However, after storage of 12 months, it decreased by 7% that was 76%. When in 4℃, after storage of 5 months the germination rate was at 85%. However, after storage of 12 months it decreased by 8% which was 77%. In room temperature after storage of 5 months, germination rate was at 77%, but after storage of 12 months it decreased by 22% which was 55%. When seeds were stored in vinyl container, it was observed that the germination rate was at 86% after 5 months of storage, which was 9% higher than seed stored in paper which was 77%. After 12 months storage, seed in vinyl container had a germination rate of 71%, which was 3% higher than seed in paper at 68%. Conclusion : It is concluded that the proper time of seed gathering of Adenophora triphylla var. japonica Hara. is during the first ten (10) days of October to mid-October. When the long time storage is needed, below zero temperature with vinyl container is more appropriate.
        6.
        2016.10 서비스 종료(열람 제한)
        Background : Adenophora triphylla var. japonica Hara. is one of the important oriental medicinal herbs being used to cure lung/respiratory diseases. It belongs to the five Sam (ginseng) including Panax ginseng, Salvia miltiorrhiza, Sophora flavescens, and Scrophularia buergeriana. In 2015, Korea produced 72 tons of medicinal herbs in a 14-hectare area and imported 24 tons valued at US$95,000. This study was carried out to investigate the effect of several biopesticides to control leaf spot of A. triphylla var. japonica Hara. Methods and Results : One year plants at the Department of Herbal Crop Research, NIHHS, RDA were used. The treatments used biopesticides such as plant extracts (BP), microbial agent (DM), microbial agent (PJ), sulfur powder (HS), and controlled chemicals (ST), while non treatment (NT) was used as control. After the early part of disease outbreak, the plants were treated four times with 7 days interval. The incidence of leaf spot, efficacy, phytotoxicity and control value were investigated. Based on the efficacy test, incidence of leaf spot is lowest at 15.6% in plant extracts (BP). Other biopesticides showed higher incidence - 16.7% for microbial agent (DM), 17.8% for microbial agent (PJ), 18.9% for sulfur powder (HS) and 71.1% for non treatment (NT), compared with 11.1% in controlled chemicals (ST). The microbial agent (PJ), sulfur powder (HS), plant extracts (BP) and microbial agent (DM) were not damaged in the phytotoxicity test. In the test of application dose, time and methods, the control value was highest in plant extracts (BP) at 78.1%, followed by microbial agent (DM) at 76.6%, microbial agent (PJ) at 75.0%, and sulfur powder (HS) at 73.4% , compared with controlled chemicals (ST) at 84.4%. Conclusion : It is possible to use biopesticides at the proper time to prevent leaf spot in Adenophora triphylla var. japonica Hara.
        7.
        2016.10 서비스 종료(열람 제한)
        Background : Adenophora triphylla var. japonica Hara. is used to cure respiratory/ lung diseases, which makes it an important oriental medicinal herb. It is one of the five Sam (ginseng), which includes Panax ginseng, Salvia miltiorrhiza, Sophora flavescens, and Scrophularia buergeriana. In 2015, Korea imported 24 tons of medicinal herbs worth US$95,000. This study was carried out to investigate the effect of several mulching materials on the growth and root yield of A. triphylla var. japonica using organic fertilizer. Methods and Result : Seeds of A. triphylla var. japonica were collected at the nursery of the Department of Herbal Crop Research, NIHHS, RDA in 2015. Mulching materials used are black plastic, black woven fabric, and biodegradable plastic. Hand weeding was done to serve as control. The soil was fertilized two months before planting. Seeds of A. triphylla var. japonica were sowed in tray in early March and were allowed to grow for two months. It was planted in early May with planting density of 30 ㎝ x 15 ㎝ and was covered with various mulching materials. Parameters investigated are survival rate, aerial part and root growth characteristics, and yield at harvest time. Results showed that biodegradable plastic is most favorable for plant growth with height of 17.2cm, leaf length of 13.4cm and leaf width of 5.6 ㎝. Dry plant weight was heaviest in biodegradable plastic treatment at 2.8 g, and lightest at 2.5 g when planted without mulch. Biodegradable plastic has the highest dry root weight of 19.3 g, followed by black vinyl (18.4 g), woven fabric (18.3 g) and without mulch (17.9 g). The yield obtained per 10 a was highest in biodegradable plastic treatment at 174 ㎏, while black vinyl and woven fabric treatments produced 169 ㎏ and 160 ㎏, respectively. Plants without mulch had the lowest yield of 157 ㎏. Conclusion : In the above results, biodegradable plastic and woven fabric are considered suitable mulching materials for the cultivation of A. triphylla var. japonica.
        13.
        2003.04 KCI 등재 서비스 종료(열람 제한)
        “Joeun” is a new semi - hard wheat variety with early maturity and good milling quality. It was developed from a cross between “Eunpamil” and “Suwon 242” at the National Crop Experiment Station, RDA. “Eunpamil” as a female parent was medium in plant heigh