• 화약ㆍ발파
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• 제18권3호
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• pp.29-40
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• 2000

Emulan은 ANFO와 bulk Emulsion(Emulite)의 흔합물로서 ANFO입자 사이의 공간은 내수성을 가진 Emulite로 채워지기 때문에 에너지와 밀도가 확실하게 증가하며 뛰어난 내수성을 가진다. 따라서 높은 장전밀도와 고 함유 에너지로 인하여 ANFO 대비 천공 미터당 암석 파쇄량을 40 %이상 증가시킬 수 있으며 저항선과 공간격을 각각 20%이상 증가시킬 수 있다. 특히, 습윤상태가 심한 장소에서 ANFO를 대신하여 가장 경제적인 폭약임이 확인되었다. 본 연구에서는 최신 Bulk-type의 폭약(Emulan)과 AFPO 및 Emulsion계 폭약을 각각 사용하여 현장의 적용성, 상호 발파효과 및 효율성과 경제성 비교를 통하여 앞으로의 대규모 노천현장이나 석산에서 보다 적절하게 사용할 수 있는 화약류에 대하여 알아보고자 하였다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.83-86
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• 2003

Soil Aquifer Treatment (SAT) is a technique in which secondary- or tertiary-treated wastewater is infiltrated through unsaturated soil and stored in the saturated zone. In SAT, contaminants are removed by physical and biochemical reactions taking place in soils. In this study, a numerical model was developed to predict changes in water quality during SAT operations. The contaminant species considered in the model were ammonium, nitrate, dissolved organic carbon, and dissolved oxygen. The model was calibrated against experimental data obtained from one dimensional soil column tests conducted for 84 days. The calibrated model will be used to find out optimum conditions for the pilot- and regional-scale SAT operations to be scheduled for the next phase of this project.

• 기술사
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• 제15권2호
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• pp.3-15
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• 1982

The study on prevention measures for vibration and excavation of tunnel for the #3, #4, Seoul Subway. In the Seoul subway tunnel blasting, the drilling pattern and prevention method to seismic vibration are as follows as well as for adaptions of NATM, the supportings of roof and wall holes are arranged with control blasting. 1. The blasting is executed basically using the low velocity explosive such as slurry, Nitrate ammonium explosive, and F-I and F-II explosive for control blasting substituting of existing dynamite. 2. The cut holes are arranged with burn cut pattern and also must be arranged with M/S electrical delay caps substituting of ordinary do]ay caps. 3. Jack leg drills are used in Five Job sites and a jumbo drill in one job site. 4. In performance of safety work and in maintenance of building safety. The drilling length for blasting will not exceed 1.20 meter for round so that the vibration value shall carry below 0.3cm/sec. The harmonizing of better powder, better drilling machine and better technique is only the way of improving tunnelling efficiency and less vibration will help the dereasing of accidence.

• Asian Journal of Atmospheric Environment
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• 제8권2호
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• pp.69-80
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• 2014

It is often assumed that atmospheric observations at remote sites represent long-range transport of airborne material, and local influences are overlooked. We evaluated the impact of local input on the rainwater composition at Gosan Station, a strategic site for monitoring the continental outflow from Asia. We analyzed a 14-year record of rainwater chemical composition archived by the Korea Meteorological Administration and detected local terrestrial contribution for nitrate, sulfate and ammonium. We also measured the chemical composition of rainwater sampled simultaneously at multiple locations within the premises of the Gosan Station, from which local influence with meter-scale spatial heterogeneity could be discerned. We estimate that the local input accounted for at least ~10% of the wet deposition of nitrogen and ~12% of the wet deposition of sulfur during the 14 years. This highlights the significance of the local influence, which should be carefully assessed when interpreting atmospheric observations at this site.

• Journal of Biosystems Engineering
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• 제28권4호
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• pp.335-342
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• 2003

A simple disposable thick-film potentiometric strip has been developed and evaluated for hydroponics application. The strip consisted of low ion-selective electrodes (ISE) fabricated by screen-printing technology. The electrochemical responses of ion sensors for nitrate, ammonium, potassium, and magnesium were measured with specially designed 16-channel low voltage signal transducers. The analytical characteristics of the sensors were comparable with those of conventional ISE sensors. The thick-film sensors exhibit linear relationships over five concentration decades. The concentration of N $O_3$ - ion in standard solution can be determined by direct potentiometric measurements without any conditioning before measurements. However, measurement of $K^{+}$, N $H_4$$^{+}$, and $Mg^{2+}$ ionic concentrations in nutrient solutions seems not feasible.

• KSBB Journal
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• 제5권4호
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• pp.347-353
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• 1990

The effects of nutrients and cell aggregate size on the cell growth of D. carota and the biosynthesi of carotenoid were investigated. Highest carotenoid content was obtained with sucrose as a carbon source and the equal ratio of ammonium to nitrate. High phosphate concentration stimulated the carotenoid biosynthesis in D. corota. 2,4-D inhibited the cell growth but stimulated the specific carotenoid content at high concentration. By modifying the medium composition based on these findings, three times higher specific carotenoid content and 2.5 times higher total carotenoid content were obtained as compared with the results obtained with basic MS media. Biosynthesis of carotenoid was found to be affected by cell aggregate size; high carotenoid production was obtained from the large aggregated cells resulted from high sucrose concentration.

• 한국세라믹학회지
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• 제25권1호
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• pp.66-72
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• 1988

The effect of salts on the formation of ${\alpha}$-hemihydrated gypsum at boiling temperature under atmospheric pressure was studied by the solubility measurement method, and the formation of ${\alpha}$-hemihydrated gypsum from by-product gypsum of phosphoric acid process in the salts solution were investigated. The order of catalytic effect of salt on the formation of ${\alpha}$-hemihydrated gypsum are as follows: NH4Cl>NaCl>NaNO3. In the salts solution of sodium nitrate, sodium chloride, and ammonium chloride, prismatic ${\alpha}$-hemihydrated gypsum was obtained and the crystal form was converted to needle form in complex solution with sulfuric acid. The P2O5 content in gypsum was largely decreased in this atmosphoric solution process.

• Mycobiology
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• 제36권1호
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• pp.1-9
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• 2008

Sixty three species and 5 varieties belonging to 30 fungal genera were collected from 75 soil samples. Cultivated (29 genera and 58 species + 5 var.), desert (22 and 35 + 2 var.) and saline soil (21 and 41 + 1 var.) fungi were recovered on glucose-, cellulose- and 50% sucrose-Czapek's agar at $28^{\circ}C$. The most common genera were Alternaria, Aspergillus, Emerieella, Fusarium, Mycosphaerella, Nectria and Penicillium. The most prevalent species from the three types of soils on the three types of media were Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emerieella nidulans, Fusarium oxysporum, Myeosphaerella tassiana, Nectria haematococca and Penicillium ehrysogenum. Chaetomium globosum was in the top of fungi in producing endo-$\beta$-1,4-glucanases among the 42 tested isolates obtained from soils on cellulose-Czapek's agar. Maximum production of this enzyme by C. globosum obtained after 6 days of incubation at $30^{\circ}C$ with culture medium containing maltose as a carbon source and ammonium nitrate as a nitrogen source and pH initially adjusted to 6.

• Archives of Pharmacal Research
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• 제19권3호
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• pp.240-242
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• 1996

We have reported the convenient biomimetic methodology for the synthesis of all kinds of substituent pattern benzo[c]phenanthridine alkaloids (Hanaoka et al., 1990; Hanaoka et al., 1991). Regioselective demethylation of C-8 position on oxyfagaridine (5), an intermediate for the synthesis of Fagaridine (4), would afford the precursor for the synthesis of Isofagaridine because the strong hydrogen bonding between amide and hydroxyl group of C-7 position probably resists to be reacted with week base and electrophiles. Thus, a selective alkylation of dihydroxy compound supposed to be possible and be lead to the target compound, Isofagaridine.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.253.1-253.1
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• 2013

RF 마그네트론 스퍼터링법으로 증착된 Al-doped ZnO 박막을 씨드층으로 하고, zinc nitrate hexahydrate, hexamethylenetetramine (HMTA), ammonium chloride (AC) 및 polyethyleneimine (PEI)를 반응용액으로 한 수열합성법으로 ZnO 나노와이어를 성장시켰다. ZnO 나노와이어의 성장 공정 중 반응 용액내에 DC 바이어스를 인가하고, DC 바이어스의 인가 유무 및 인가 DC 바이어스 전압의 크기 변화에 따라 성장시킨 ZnO 나노와이어의 특성을 비교분석하였다. 다양한 공정변수 변화에 따라 수열합성법으로 성장시킨 ZnO 나노와이어 시편들을 SEM 분석을 통해 특성분석을 수행하였다.