• Journal of Plant Biotechnology
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• v.31 no.4
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• pp.295-300
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• 2004

This article was conducted to induce the transgenic hairy roots and determine the effect of culture conditions on optimum growth of hairy roots by Agrobacterium rhizogenes strain, 15834 in Lycium chinense Miller. Hairy roots of L. chinense Miller. were induced from leaf segments by co-cultivation with A. rhizogenes. When the hairy roots were cultured in various MS medium strength and sucrose concentrations, the highest growth of hairy roots was observed in half-strength MS media supplemented with 3% sucrose, respectively. In air lift bioreactor cultures, the liquid medium contained with 1/2 MS and 3% sucrose was also the best for optimum growth of hairy roots.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.433-441
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• 2004

국내 발파 현장에서 사용되고 있는 폭약류에 강력한 폭굉력을 충분하게 발휘하기 위해서는 뇌관(Blasting cap, Detonator)의 역할이 중요하다. 그리고 이 뇌관의 정밀성에 따라 발파 효율의 차이가 있게된다. 초기의 도화선 및 공업뇌관에서 시작하여 현재 정밀성 면에서는 MS(Milli Second)뇌관의 경우 20ms또는 25ms의 정밀한 시차로 순차적으로 기폭함으로써 발파효과의 극대화와 소음 및 진동제어에 큰 효과를 이루었으나, 최근 개발된 진자뇌관의 경우 자체 IC회로를 내징하여 $1{\sim}2ms$의 초정밀시차(오차범위 $0.1{\sim}0.2ms$이내)의 구현이 가능해짐에 따라 이를 적절히 조합하여 설계함으로써 각종 제어발파, 파쇄도 향상, 암손상영역 저감 등의 효과에 대해 국외에서 연구가 진행되고 있는 것으로 알려지고 있다. 그러나 우리나라와 같이 도심지 발파 및 터널이나 노천 현장 근거리에 보안물건이 위치해 있어 진동제어가 절실히 필요한 상황에서 진동제어에 효과가 있는 것으로 알려진 전자뇌관에 대한 연구가 이루어지고 있지 않은 상황에서 본 연구는 앞으로 이루어질 전사뇌관에 대한 수많은 연구에 기초자료를 제공하고자 실시하였다. 본 연구에서는 이를 위해 국내에서 최초로 2003년 9월 23일 강원도 양구 지역읜 00터널에 전자뇌관을 이용한 시험발파를 실시하였고, 발파에 의한 진동 등을 조사하여 그 효율성을 검토하였다. 이를 위해 전자뇌관의 특성과 장점을 최대한 살리기 위하여 각공을 발파하는 방식, 즉 1지발에 1공을 발파하는 방식을 채택하고 비전기 뇌관과 전자뇌관으로 설계를 하여 각각의 발파효율을 비교하여 보았다. 그 결과 발파신동의 경우 비전기뇌관을 이용하여 1공씩을 1지발로 발파를 한 경우에는 18${\sim}$56%의 진동저감 효과가 있었고, 번 설계에 의해 진해오딘 발파에 비하여는 최대 70% 이상의 진동저감 효과가 있는 것으로 나타났다.

• Journal of the Korean Chemical Society
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• v.60 no.6
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• pp.452-456
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• 2016

• Explosives and Blasting
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• v.34 no.4
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• pp.40-45
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• 2016

Sites, where explosives are used, are constantly under constraint of vibration and noise levels. If a sensitive area is located nearby the sites, mechanical excavation has been preferred rather than blasting. Recently, however, blasting using electronic detonators is applicable in the areas, where previously should be excavated by mechanical methods. $HiTRONIC^{TM}$ is a fourth-generation detonator that utilizes Hanwha Corporation's advanced electronic technology. The detonator contains IC-Chip, which allows delay times between 0~15,000ms with 1ms interval. Furthermore, the product can provide high accuracy(0.01%) for accurate-blasting. Electronic detonator is widely used in highway and railway construction sites, large limestone quarries, and other works. In this paper, several sites, in which HiTRONIC was used, are introduced in order to enhance understanding of electronic detonator.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.153-157
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• 2000

Hydrolysate which inhibit the Angiotensin I-converting enzyme (ACE) was prepared from mackerel muscle by pretense. The ACE inhibitory activity of mackerel muscle hvdrolysate (MMH) was $967 {\mu}g of IC_(50)$. ACE inhibitory peptides were isolated by ultrafiltration, gel permeation column chromatography (GPC), reversed phase column chromatography(RPC), reversed phasehigh performance liquid chromatography (RP-HPLC), and gel permeation high performance liquid chromatography (GP-HPLC) from the MMH. The amino acid sequence of the ACE inhibitory peptides was Tyr-Val-Ala. The $IC_(50)$ of this peptide for ACE from rabbit lung was $1.4 {\mu}M$.

• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.100-104
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• 2006

The in vitro antimicrobial and antioxidant activities of the essential oil and methanol extracts of Ledum palustre L. were investigated. Using GC-MS analysis, we identified 37 compounds in the essential oil, constituting 87.58% of the total oil. There are several monoterpenes, of which sabinene is the major compound ($16{\sim}17%$). There are several oxygenated monoterpenes of which terpinen-4-ol(7.6%) and myrtenal (3.5%) are the main constituents. $\beta$-Selinene, a-selinene, $\gamma$-elemene, a-caryophyllene are the main sesquiterpenes ($2{\sim}6%$ range). The oil strongly reduced the diphenylpicrylhydrazyl radical ($IC_{50}=1.56{\mu}g/mL$) formation and exhibited a hydroxyl radical scavenging effect in the $Fe^{3+}-EDTA-H_2O_2$ deoxyribose system ($IC_{50}=2.7{\mu}g/mL$), and also inhibited the nonenzymatic lipid peroxidation of rat liver homogenate ($IC_{50}=13.5{\mu}g/mL$). The polar phase of the extract showed antioxidant activity. The oil showed antimicrobial activity against Streptococcus pneumoniae, Clostridium perfringens, Candida albicans, Mycobacterium smegmatis, Acinetobacter lwoffii and Candida krusei while the water-insoluble parts of the methanolic extracts exhibited slight or no activity. This study confirms that the essential oil of Ledum palustre L. possesses antioxidant and low antimicrobial properties in vitro.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.187-194
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• 2009

Two pyranocoumarin constituents have been isolated from Angelica gigas and were identified as decursinol angelate (1) and decursin (2) by means of NMR analysis, respectively. Human acyl-CoA:cholesterol acyltransferase (hACAT) inhibitory activity of decursinol angelate (1) and decursin (2) was evaluated. Decursin (2) showed significantly inhibitory activity against hACAT1 and hACAT2 with $IC_{50}$ value of 137 and $168\;{\mu}M$, respectively, whereas decursinol angelate (1) exhibited weak ACAT inhibitory activity. These results suggested that decusin from A. gigas might be effective for the prevention and the treatment of hypercholesterolemia or atherosclerosis by inhibitory effect on hACAT. The contents of decursinol angelate (1) and decursin (2) were analyzed in various parts of A. gigas including flower, seed, leaf and root using LC/MS/MS (ESI, positive ion mode, MRM mode). The content of decursinol angelate was increased in order of flower, seed, leaf, and root and decursin content was increased in order of flower, seed, leaf, and root. It was expected that unused parts including leaf and flower of A. gigas might be useful as new functional sources by their high contents of decursin and decursinol angelate.

• Korean Journal of Food Science and Technology
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• v.34 no.1
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• pp.114-117
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• 2002

During the screening of inhibitors of caspase-3 induction in U937 human monocytic leukemia cells from natural sources, Forsythiae fructus, which showed a high level of inhibition, was selected. And then, the compound was purified from the methanol extract using silica gel column chromatography and HPLC. The inhibitor was identified as rengyolone, by spectroscophic methods of ESI-MS, $^1H-NMR$, $^{13}C-NMR$, DEPT, and HMBC. Rengyolone showed inhibitory activity of caspase-3 induction, a major protease of apoptosis cascade, with an $IC_{50}$ value of $6.25\;{\mu}g/mL$ after 7 h of treatment in U937 cells. It also showed inhibitory activity of caspace-1 induction, with an $IC_{50}$ value of $7.50\;{\mu}g/mL$ after 40 h of treatment in D10S cells. In addition, it showed protective effect against cell death with an $IC_{50}$ value of $11\;{\mu}g/mL$ on U937 cells induced by etoposide after 24 h of treatment, but did not show any cytotoxicity at the same condition without etoposide, a caspase 3 inducing agent.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.49 no.3
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• pp.1-7
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• 2012

A 9b MS/s CMOS cyclic folding A/D converter (ADC) for intelligent battery sensor and battery management systems is proposed. The proposed ADC structure is based on a cyclic architecture to reduce chip area and power consumption. To obtain a high speed ADC performance, further, we use a folding-interpolating structure. The prototype ADC implemented with a 0.35um 2P4M n-well CMOS process shows a measured INL and DNL of maximum 1.5LSB and 1.0LSB, respectively. The ADC demonstrates a maximum SNDR and SFDR of 48dB and 60dB, respectively, and the power consumption is about 110mW at 2MS/s and 3.3V. The occupied active die area is $10mm^2$.

• Analytical Science and Technology
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• v.13 no.5
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• pp.601-607
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• 2000

Lanthanum has been used as one of the burnup monitor in spent nuclear fuel. $U_3Si/Al$ spent nuclear fuel contains small amount of La in high concentration of U and Al. Therefore, chemical separation of La is required to remove matrix elements. At first, ion chromatography (IC) and inductively coupled plasma systems were installed in radiation shielded glove box to handle the radioactive samples. Retention behavior of uranium, aluminum, lanthanum and some interesting fission products (Sr, Zr, Y, Mo, Ru, Pd, Rh, Cs, Ba, Ce, Pr, Nd, Sm, Eu and Cd) was investigated using the CG10 column and ${\alpha}$-HiBA eluent. As all elements were eluted earlier than lanthanum in 0.2 M ${\alpha}$-HiBA eluent, a portion of U and Al was directly passed to waste using a three way valve between the column and the nebulizer. Thus it was possible to determine the lanthanum in a high concentration of U and Al matrix. Retention time of La was about 12 minutes in this separation condition. Optimum range for the determination of La in $U_3Si/Al$ spent nuclear fuel was $1-10{\mu}g/L$ (ppb) with this system and detection limit was $0.25{\mu}g/L$ in case of $200{\mu}L$ of sample volume.