• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1603-1605
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• 1997

$LiNiO_2$ is prepared by heating LiOH $H_2O$ and $Ni(OH)_2$ (mole ratio 1:1). In this study, we investigated X-ray diffraction, and charge/discharge property heat treatment condition and conductive agent sort and volume of $LiNiO_2$ prepared at various temperature and time. All $LiNiO_2$ prepared at this study showed hexagonal structure. In charge/discharge capacities, heated at $O_2$ than air and $750^{\circ}C$ than $700^{\circ}C$, specific capacity is higher. Therefore, when preliminary heat at $650^{\circ}C$ $O_2$ and heat at $750^{\circ}C$ carried out, charge/discharge property is best.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.275-278
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• 1997

We investigated effectness of sort and volume of conductive agent to charge/discharge capacity of LiMn$_2$O$_4$. LiMn$_2$O$_4$is prepared by reacting stoichiometric mixture of LiOH . $H_2O$ and MnO$_2$(mole ratio 1 : 2) and heating at 80$0^{\circ}C$ for 24h, 36h, 48h, 60h and 72h. All LiMn$_2$O$_4$cathode active materials show spinel structure. Cathode active materials calcined at 80$0^{\circ}C$ for 36h, charge/discharge characteristics and cycle stability have remarkable advantages. Used that super-s-black and 20wt% as conductive agent in LiMn$_2$O$_4$, it is excellent than property of cathode used Acetylene black or mixture of Super-s-black and acetylene black at charge/discharge capacity and cycle stability. Also, specific efficiency of cathode is excellent as over 98% and that of first cycle is excellent as 92%.

• 화약ㆍ발파
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• 제8권1호
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• pp.3-16
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• 1990

The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill $\varphi{70mm}$ on the calcalious sand stone(sort-moderate-semi hard Rock). The total numbers of feet blast were 88. Scale distance were induces 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagtion Law in Blasting Vibration $V=K(\frac{D}{W^b})^n$ where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites (m) W : Maximum Charge per delay-period of eighit milliseconds or more(Kg) K : Ground transmission constant, empirically determind on th Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity $D/W^b$ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three graups. Cabic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge per delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over loom distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m----under l00m----- $V=41(D/3\sqrt{W})^{-1.41}$ -----A Over l00m-----$V= 121(D/3\sqrt{W})^{-1.66}$-----B K value on the above equation has to be more specified for furthur understang about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• 기술사
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• 제24권6호
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• pp.97-105
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• 1991

The cautious blasting works had been used with emulsion explosion electric M/S delay caps. Drill depth was from 3m to 6m with Crawler Drill ø70mm on the calcalious sand stone (soft-moderate-semi hard Rock). The total numbers of fire blast were 88 round. Scale distance were induces 15.52-60.32. It was applied to propagation Law in blasting vibration as follows. Propagation Law in Blasting Vibration (Equation omitted) where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W : Maximum Charge per delay-period of eighit milliseconds o. more(kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity D / W$^n$ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three graups. Cubic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge per delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over 100m distance because the frequency is verified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30 ‥‥‥under 100m ‥‥‥V=41(D/$^3$√W)$\^$-1.41/ ‥‥‥A Over 100 ‥‥‥‥under 100m ‥‥‥V=121(D/$^3$√W)$\^$-1.56/ ‥‥‥B K value on the above equation has to be more specified for furthur understang about the effect of explosives, Rock strength. And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• 화약ㆍ발파
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• 제9권4호
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• pp.3-12
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• 1991

The cautious blasting works had been used with emulsion explosion electric M /S delay caps. Drill depth was from 3m to 6m with Crawler Drill 70mm on the calcalious sand stone (soft-moderate-semi hard Rock) . The total numbers of feet blast were 88. Scale distance were induces 15.52-60.32. It was applied to Propagation Law in blasting vibration as follows .Propagtion Law in Blasting Vibration V=k(D/W/sup b/)/sup n/ where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W ; Maximum Charge per delay -period of eight milliseconds or more(Kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity D/W/sup b/ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three groups. Cabic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over loom distance because the frequency is varified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m--under 100m----V=41(D/ W)/sup -1.41/-----A Over l00m---------V=121(D/ W)/sup -1.56/-----B K value on the above equation has to be more specified for furthur understand about the effect of explosives. Rock strength, And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• 대한환경공학회지
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• 제22권12호
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• pp.2227-2238
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• 2000

수중 부유입자의 효과적인 제거 방안을 모색하고자 $CaCO_3$로 구성된 부유물의 계면화학적 특성을 고찰하였다. pH에 따른 전기영동도 측정에서는 수중 $OH^-$의 작용으로 pH가 상승함에 따라 electrokinetic potential은 음의 방향으로 변환하는 것으로 나타났다. 계면활성제는 부유물의 안정성에 영향을 끼치는 바, 계면활성제의 농도 및 전하에 따라 영향을 미치는 양상이 다르게 나타났다. 무기응집제의 경우에 있어서도 그 전하가 및 농도에 따라 부유물의 계면화학적 거동이 달라졌으며 이는 DLVO 이론에 의거하여 작성된 potential energy의 변화추이와 관련하여 이론적으로 해석될 수 있었다. Non-specific adsorption은 전기이중층의 압축을 초래하여 electrokinetic potential의 절대값 감소를 야기시켰으며 specific adsorption은 부유입자의 IEP 및 PZC가 상호 반대방향으로 이동하는 결과를 나타내었다.

• Korean Chemical Engineering Research
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• 제49권1호
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• pp.10-14
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• 2011

철 이온 교환방법에 의해 메조기공을 갖는 활성탄소 섬유(ACF)를 제조하고, 이를 사용하여 전기 이중층 커패시터(EDLC)의 전극소재 성능을 조사하였다. 질산처리에 의해 제조된 메조기공 ACF는 비표면적이 1,249, 664 $m^2/g$이고, 메조 기공 분율이 70.6-81.3%이고, 평균 기공크기는 약 2.78~4.14 nm이다. 질산처리시간이 짧을수록 비표면적이 크고 메조 기공이 적게 발달됨을 알 수 있었다. 전기이중층 커패시터의 성능을 조사하기 위해서, 메조기공 ACF, 도전제, 바인더를 사용하여 단위 셀을 제조하였으며, 유기 전해질을 사용하였다. 2시간 질산으로 처리된 ACF의 비 축전양은 0.47 $F/cm^2$이고, 20회 충.방전 테스트에서 안정된 실험결과를 얻을 수 있었다. EDLC의 전기화학적 성능은 ACF 전극의 비표면적에 크게 영향을 받으며 메조기공은 전하의 확산저항을 감소시키는 것을 알 수 있었다.

• 터널과지하공간
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• 제11권3호
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• pp.248-256
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• 2001

실린더 컷은 터널 굴착단면의 크기에 관계없이 널리 이용된다. 본 연구에서는 발파당 굴진장을 중대시키기 위하여 종래의 방법과 다른 새로운 방법을 제안하였다. 이 방법의 새로운 패턴은 그림과 같으며, 각 단계별로 상세한 저항선, 공간간격은 별도 그림과 같다. 새로운 실린더 컷 방법과 종래의 방법과의 결과는 다음과 같다. 종래 방법은 굴진장이 천공장의 90∼95%인데 비하여 새로운 방법은 대체로 99.5%이다. 비장약량이 1.363kg/㎥에서 1.297로 약 5% 감소되며, 비천공장이 2.393 m/㎥에서 2.130으로 약 8%o감소 된다. 그밖에 지반진동, 비산, 파쇄암의 크기 등이 종래 방법에 비하여 우수함을 확인하였다.

• 펄프종이기술
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• 제43권3호
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• pp.88-97
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• 2011

We carried out cationization of Dak pulp (paper mulberry bast fiber pulp) which is raw material of Hanji (Traditional Korean Paper) using a (3-chloro-2-hydroxypropyl) trimethyl ammonium chloride to improve dyeability during a dyeing of Hanji with Gardenia (Gardenia jasminoides) and smoke tree (Cotinus coggygria). Fiber specific charge densities were determined using polyelectrolyte titration method and K/S values of dyed Hanji was calculated by Kubelka-Munk equation. As the result, fiber specific charge density increased with degree of cationization. Colors of Hanji dyed with Gardenia did not vary significantly with degree of cationization, but cationized Hanji dyed with smoke tree showed a large increase of a* value and reddish yellow color. After-mordanting did not decrease K/S value of dyes with cationized Hanji. K/S values of dyed Hanji decreased with increasing dyeing temperature. For smoke tree, the cationization impair lightfastness of dyed Hanji without mordant. After-mordanting with copper acetate or iron chloride improved lightfastness of dyed Hanji.

• 자원리싸이클링
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• 제11권3호
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• pp.37-45
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• 2002

마찰대전 분리는 서로 상이한 두 물체를 마찰시켜 각자 반대극성으로 하전시킨 후 전기장에 통과시켜 분리하는 기술이며, 이때자 물질의 하전극성은 work function에 의해 각기 다른 극성으로 하전된다. 본 연구에서는 마찰대전을 이용한 정전분리에 기본이 되는 각종 플라스틱의 work function을 알아보는 데 중점을 두었으며 마찰대전 후 하전량에 따른 분리 효율을 도출하여 최적의 운전조건을 위한 하전특성을 알아보았다. 플라스틱 시료는 2가지의 샘플을 가지고 실험하였으며. 이를 각기 다른 재질의 드럼형 마찰하전장치를 이용하여 대전을 시켰다. 또한 Faraday Cage를 이용하여 하전량을 측정한 후 work function을 도출하였다. 하전된 입자는 $\pm$20 kV의 전장에 통과시켜 분리실험을 수행하고 이를 통해서 하전량과 분리효율간의 상관관계를 도출하였다.