• Explosives and Blasting
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• v.19 no.3
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• pp.39-47
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• 2001

Bulk-Emulsion system은 미주나 서구 유럽 등지의 발파분야에 있어 선구적인 역할을 수행하여 왔던 나라에서는 이미 보편화된 시스템으로 ANFO 다음으로 노천이나 터널 굴진에 널리 적용되고 있다. Bulk-Emulsion system은 제조, 저장, 운반 및 사용에 있어서 극히 안전하고 장전밀도를 증가시켜 효과적인 파쇄와 굴진률 향상을 기대할 수 있으며 발파 후가스가 매우 양호한것을 비롯하여 기계화 장전에 따른 시공 능률 향상과 작업 안전성 강화 등 많은 장점을 가지고 있다. 본 연구에서는 고속도로 터널 현장에 국내 최초로 터널용 Bulk-Emulsion system을 이용하여 총 15회에 걸쳐 시험발파를 실시하였으며 이 결과를 토대로 하여 Bulk-Emulsion system 적용에 따른 효과와 문제점을 알아보고자 하였다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.2
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• pp.107-115
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• 2009

Lately, the length of tunnel, the number of large-long tunnel over three lanes are steeply increased because of the request for high speed and straight road. Therefore, the maximization of excavation efficiency is needed in tunnel construction. Bulk Emulsion explosives charging system is the spearhead equipment using the radio remote control $&$ mechanization system compare with a traditional method Cartridge type. This study introduced the bulk emulsion explosives which is new method in tunnel blasting and verified the efficiency of bulk emulsion explosives for long-large tunnel. And we tried to compare Cartridge type efficiency with bulk emulsion explosives efficiency by the field test.

• Explosives and Blasting
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• v.26 no.2
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• pp.64-76
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• 2008

Bulk Emulsion blasts using mechanized charging system, which is generally used in foreign countries, have recently introduced and gradually increased in Korea. The Bulk Emulsion are safe and able to increase the charging density for improvement of fragmentation and advancement especially in tunneling, and minimizing environmental problem. Because of less toxic gas generation, the explosives are called, namely ech-friendly products. There are two kinds of Bulk Emulsion; one is for open cut and the other is for tunneling. According to features of blast sites and its purpose, the compositions are different, but the principle is the same. In this study, trial blasts using Bulk Emulsion for tunneling had executed at 10 sites in Korea. The major result of the major job-sites is the following. First of all, compared with cartridge explosive, Bulk Emulsion was able to increase its charging density up to $35{\sim}60%$, to decrease the blast holes to approximately $10{\sim}30%$ down, and the advancement was improved up to $8{\sim}20%$ and also 30% up in its fragmentation. Toxic gas production after cartridge blasting showed 34.44ppm of its CO. Bulk Emulsion, however, showed 20.13ppm, which was 58.45% production of the cartridge explosive, and NOx was below 2ppm. The mechanized charging system of Bulk Emulsion should be applied to large sized tunnel blasting, long advanced tunnel which can secure the advancement of over $4{\sim}5m$, and the sites required finishing rapidly.

• Proceedings of the KSEE Conference
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• 2004.08a
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• pp.77-95
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• 2004

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1077-1083
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• 1999

This study was aimed to evaluate the effectiveness of hydrophilic, lipophilic antioxidants and emulsifiers by HLB (hydrophilic lipophilic balance) in different oil systems. Lipophilic antioxidant (${\delta}-tocopherol$), hydrophilic antioxidant (gallic acid) and emulsifier(lecithin, tween 20, span 60) were evaluated in relation to oil stability in bulk oil system (soybean oil) and emulsified with Tween 80 at $60^{\circ}C$. In the storage test ($60^{\circ}C$), gallic acid was more effective on the stability of oil oxidation than ${\delta}-tocopherol$ in bulk and emulsion system. Lecithin as a hydrophilic emulsifier was more effective than tween 20 on the stability of oil oxidation in bulk and emulsion system. Also span 60, a lipophilic emulsifier, was more effective than tween 20, a hydrophilic emulsifier, in bulk and emulsion systems.

• Explosives and Blasting
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• v.24 no.1
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• pp.29-37
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• 2006

The demand of the bulk emulsion explosives is being increased more and more by using the mechanization loading system in a domestic tunnel sites. Thus, a rational design criteria that is suitable for rock and circumstance condition has been required. In this study, authors investigated a optimum specific charging weight and resonable charging weight based on domestic blasting construction cases, which were performed by using a mechanization bulk emulsion explosives loading system up to now. Authors also analyzed the blasting results and got the following formula $({\Upsilon}= 0.669 + (0.0154{\times}RMR),\;r=0.81)$ from the relationship between a optimum specific charging weight of bulk exp. and rock mass rating. A range of resonable charging weight with a drilling depth is calculated considering a rock conditions.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.560-565
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• 1998

The purpose of this study was to investigate any differences in the efficiency of various antioxidants for the three types of substrates such as corn oil in water (O/W) emulsion, water in com oil (W/O) emulsion, and bulky corn oil. ${\alpha}$-Tocopherol (${\alpha}$-Toc) at 0.01 or 0.02%, ascorbic acid (AsA), ascorbyl palmitate (AP), and BHT at 0.02% were added separately to the prepared O/W emulsion, W/O emulsion, and bulk oil, and their antioxidative effects were compared. The mixture of ${\alpha}$-Toc ind AsA or AP at the level of 0.02% also was tested to observe any synergistic effect. Oxidation was made by storing at 42${\pm}$1$^{\circ}C$ for 25 days and the oxidative stability was determined by peroxide value and conjugated dienoic acid with time fluctuation of storage. The results were as follows: 1. In case of O/W emulsion, the order of antioxidative effect was AP> ${\alpha}$-Toc+AP>${\alpha}$-Toc+AsA>AsA>BHT. 2. In case of W/O emulsion, the order of antioxidative effect was AsA>AP>${\alpha}$-Toc+AsA>BHT. ${\alpha}$-Toc+AP mixture showed the prooxidant effect rather than synergistic effect. 3. In case of bulk oil, the order of antioxidative effect was AsA>AP>${\alpha}$-Toc+AsA>${\alpha}$-Toc+AP\ulcornerBHT. Therefore, AsA, a hydrophilic antioxidant, was more effective in W/O emulsion system than in O/W emulsion system, while the opposite trend was found in AP, a lipophilic antioxidant. AsA, a hydrophilic antioxidant, was more efficient in bulk oil of anhydrous substrate. ${\alpha}$-Toc showed prooxidant effects in all substrates.

• Tunnel and Underground Space
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• v.15 no.3 s.56
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• pp.177-184
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• 2005

The Sapaesan tunnel, the longest twin tube tunnel (4km) in Korea with 4 lanes each, is under construction with two years of delayed schedule because of the strong opposition from environmental bodies. Therefore, maximizing the construction efficiency was needed in tunnel project to compensate for time delay. This study includes improvements in the construction of the Sapaesan tunnel such as increasing excavation length and changing excavation sequence. In this paper the system for predicting tunnel face ahead is also introduced. Bulk-Emulsion explosive and Cylinder-Cut method were adopted in tunnel blasting to increase the excavation length. Optimum tunnel excavation step was designed to make up delayed time. Tunnel foe mapping, TSP survey and geological prediction system using computerized jumbo-drill were performed fnr safe construction of long and large twin tube tunnel.

• Food Science and Preservation
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• v.30 no.2
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• pp.334-346
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• 2023

The antioxidant ability of 80% ethanolic extract of nutmeg seed (NM80) was evaluated using in vitro assays and bulk oil and oil-in-water (O/W) emulsion matrices. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) cation radical scavenging, and oxygen radical antioxidant capacity (ORAC) in vitro assays were used to evaluate the antioxidant ability of the extract. The DPPH radical scavenging activities of 25, 50, 100, and 200 ㎍/mL NM80 were 12.5, 20.9, 35.1, and 62.8%, respectively, while the ABTS cation radical scavenging activities were 2.7, 6.5, 30.5, and 29.8%, respectively, demonstrating a dose-dependent effect. The ORAC value was significantly higher at an NM80 concentration of 25 ㎍/mL than the positive control (p<0.05). The conjugated dienoic acid (CDA), ρ-anisidine, and tertiary butyl alcohol values in 90-min-heated corn oil containing 200 ppm of NM80 were significantly reduced by 3.26, 16.94, and 17.34%, respectively, compared to those for the sample without NM80 (p<0.05). However, the headspace oxygen content and CDA value in the O/W emulsion containing 200 ppm of NM80 at 60℃ had 6.29 and 82.85% lower values, respectively, than those for the sample without NM80 (p<0.05). The major volatile compounds of NM80 were allyl phenoxyacetate, eugenol acetate, and eugenol. NM80 could be an effective natural antioxidant in lipid-rich foods in bulk oil or O/W emulsion matrix.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.294-299
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• 1998

To prove pseudo-homopolymerization(PHP) method indirectly for general system which includes more than one growing radicals per particle, Mayo-Lewis equation of bulk copolymer system was derived form probability equation about instantaneous copolymer composition of emulsion copolymer system during interval II. From Extended Smith-Ewart equation proposed by Ballard et al. in emulsion copolymerization, exact solution was obtained for 0-1 system (i.e., the system containing no more than one growing radical per particle). From the exact solution, average number of radicals per particle and instantaneous copolymer composition were predicted to reach the steady state which a few minutes. So the reliability of this approximation method could by proved directly for 0-1 system. Styrene-butadiene(St-Bu) and Styrene-methyl methacrylate (St-MMA) system were used for model calculations.