• 한국수소및신에너지학회논문집
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• 제10권2호
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• pp.141-149
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• 1999

현재 수소저장 합금을 이용하여 2차전지의 음극으로 개발되고 있는 $AB_5$ type의 $(LM)Ni_{4.49}Co_{0.1}Mn_{0.205}Al_{0.205}$ 조성의 수소저장합금과 $AB_2$ type의 $Ti_{0.6}Zr_{0.4}V_{0.6}Ni_{1.4}$ 조성의 수소저장합금에 Pd를 0, 0.5, 1, 2 wt% 첨가한 조성을 진공 중에서 arc 용해를 하였다. 용해된 합금의 조직과 결정구조를 SEM, XRD로 조사하였다. Pd 가 첨가되었음에도 조직이나 결정구조의 변화는 보이지 않았다. 미세한 구리분말을 합금분말 대비 3:1로 첨가하여 pellet형태의 전극을 제조하여 전극특성을 조사한 결과 Pd 첨가에 따른 초기 활성화와 급속 충방전 특성은 크게 변하지 않았다. 그러나 싸이클 수명에 있어서는 Pd를 첨가한 전극들이 Pd를 첨가하지 않는 전극에 비해 우수하였다. $AB_5$ type 조성의 합금에서는 Pd를 2wt% 첨가한 전극, 그리고 $AB_2$ type 조성의 합금에서는 Pd를 0.5wt% 첨가한 전극에서 싸이클 특성이 가장 우수하게 나타났다.

• 한국수소및신에너지학회논문집
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• 제18권1호
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• pp.52-59
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• 2007

We investigated the effects of the addition of Mn and $AB_5$ type alloy on the electrochemical characteristics of Ti-Cr-V BCC type alloys as anode materials for Ni-MH battery. The activation behavior and discharge capacity of the BCC type alloys were significantly improved by ball-milling with the $LmNi_{4.1}Al_{0.25}Mn_{0.3}Co_{0.65}$ alloy, because the $AB_5$ type alloy acted as hydrogen path on the surface of the BCC type alloy. Among the Mn substituted alloys($Mn=0.03%{\sim}0.08%$), the $Ti_{0.32}Cr_{0.38}Mn_{0.05}V_{0.25}$ alloy ball-milled with $AB_5$ type alloy exhibited the greatest discharge capacity of $336\;mAh{\cdot}g^{-1}$. In addition, Mn substituted alloys exhibited the lower plateau pressure in P-C- T curve, the better hydrogen storage capacity and faster surface activation compared with the alloy without Mn.

• 한국동물학회지
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• 제18권2호
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• pp.51-60
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• 1975

양서류 발생에 따른 피부점액선의 조직학적 및 조직화학적 변화를 밝히고저 개구리(Rana nigromaculata) 변태 각 단계의 유생 피부조직을 10% formalin 완충액에 고정($4^{\circ}C$), paraffin에 포매, 4$\mu$m 두께로 절편한후 periodic acid-Schiff(PAS) 및 alcian blue(AB) pH 2.5, pH 1.0에 반응시켜 다음과 같은 결과를 얻었다. 1. 피부점액선의 출현은 변태 XV에서 처음으로 표피내 세포군이 형성되면서 비롯되는데 변태 XX, XXIII 및 XXIV에서 현저한 수적 증가가 있었다. 2. 피부점액선은 두 종류로 구분되는데 A형점액선은 선체부 상피세포들이 PAS와 AB pH2.5에 강양성, 경세포는 PAS에 강양성을 보이며, B형점액선의 선체부 상피세포들은 AB pH 2.5에 강양성을 보였다. 3. A형점액선은 변태 XIX에서 처음으로 내강을 형성하며 선상피내 점액질들이 PAS 및 alcian blue에 염색성을 보였고 변태가 진행됨에 따라 PAS 및 AB pH 2.5에 염색성이 점차로 증가되었다. 4. B형점액선은 변태 XX에서 처음으로 관찰되었으며 변태가 진행함에 따라 AB pH 2.5에 강양성을 보였다. 5. A형점액선과 B형점액선의 출현비는 변태 XX, 변태 XXI과 XXII, 변태 XXIII ~ XXV에서 각각 99 : 1, 7 : 3, 5.5 : 4.5였다. 6. 이상의 사실들로 미루어 양서류가 수서에서 양서로 생활양식이 변화함에 따라 피부내 수분 및 전해질의 평형을 유지하기 위해서는 피부점액선의 현저한 발달이 요구된다구 사료된다.

• 한국수소및신에너지학회논문집
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• 제8권4호
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• pp.181-185
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• 1997

The electrochemical properties of the $AB_2$-type (Zr-Ti-V-Ni-Cr-Co-Mn) metal hydride electrodes prepared by ball milling with $AB_5-type\{(LM)Ni_{3.6}Al_{0.4}Co_{0.7}Mn_{0.3}\}$(LM : Lanthanum-rich mischmetal) alloy powder as a surface activator were investigated. By ball milling with $AB_5$ type alloy powder, the activation of $AB_2$ type metal hydride electrode was accelerated resulting in an increase of discharge capacity from 35% to 85% of the maximum capacity at the first cycle. As the amount of surface activator increased the activation rate increased, whereas the discharge capacity increased with 10wt% and decreased with 20wt% addition of the surface activator. When the amount of the surface activator was kept constant as 10wt%, the discharge capacity and the activation rate increased with ball milling time up to 20 hours. However beyond 20 hours of ball milling time, they decreased drastically due to the nano-crystallization or amorphorzation of the alloy powder.

• 한국수소및신에너지학회논문집
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• 제11권4호
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• pp.189-202
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• 2000

$AB_2$ type Zr-based Laves phases alloys have been studied for potential application as a negative electrode in a Ni-MH battery. The $AB_2$-type electrodes have a much higher energy density than $AB_5$-type electrodes per weight, however they have some disadvantages such as poor activation behavior and cycle life etc. Nonetheless, the $AB_2$-type electrodes have been studied very extensively due to their high energy density. In this study, in order to develop the cycle life, the Mn of $AB_2$ alloy composition was substituted partially by Mo. The alloys were melted by arc furnace and remelted 4-5 times for homogeneity. The alloy powder was used below 200-325 mesh for experiments. The structures and phases of the alloys were analyzed by XRD, SEM and EDS, and measured the curve of a pressure-composition isotherms. The electrodes were prepared by cold pressing of the copper-coated(25 wt%) alloy powders, and tested by a half cell. The results are summarized as follows. The cycle life was improved with the increase of Mo amount in $Zr_{1-x}Ti_xV_{0.4}Ni_{1.2}Mn_{0.4}Mo_y$(x=0.3, 0.4) and the activation was faster, whereas the discharge capacity decreased.

• 한국표면공학회지
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• 제30권4호
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• pp.262-271
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• 1997

Nickel-matal hydride(Ni-MH) batteries are receiving attention as non-pollunting. high performance rehargeable energy stoage system. The performance of Ni-Mh is significantly influenced by the hydrogen storage alloy materiels used as an anode material. Recently, having discharge capacities higher than the $AB_5$-type hydrogen storage alloys, the Zr-based $AB_2$-Type hydrogen storage alloys has remaining problems regarding cycle life and self-dischareg. These problems need to be solved by improvements in the alloy design and/or surface treatment. This work investiggates the effects the effects of surface property by fluorination on $Zr_{0.7}Ti_{0.3}V_{0.4}Mn_{0.4}Ni{1.2}$ composittion $AB_2$-Type hydrogen storage alloys. EPMA, SEM and AES techniques were used for surface analysis, and the crystal structure was characterized by constant current cycling test and potential sweep methods. Fluorination was found to be effective when La-was incorporated into the alloy, and has unique morphology, higher reactivity, and at the same time formed a protective film. Through, fluorination, the cycle life of an electrode was found to increase significantly, charge/discharge characteristics of the electrode the potential difference between the charge/discharge plateau, i.e polarization(overpotential)were improved.

• 대한의생명과학회지
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• 제5권1호
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• pp.27-40
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• 1999

본 연구는 MarA와 함께 MarB가 AcrAB efflux pump를 목표로 하는지 여부, 그리고 항생제의 균체외 배출기능에 대하여 어떤 조절 작용이 있는지를 항생제 내성검사를 통하여 살펴보았다. 본 연구 결과는 MarB가 MarA와 함께 AcrAB/TolC efflux pump의 항생제 배출기 능을 억제적으로 조절한다는 것을 간접적으로 보여 주었으며, 한편 이미 알려진 대로 MarA는 acrRAB operon의 발현을 전사 수준에 서 positive regulation하므로, MarB는 AcrAB efflux pump의 기능을 억제적으로 조절한다는 것을 암시하고 있다. 그리고 MarA와 함께 MarB단백질의 작용 목표는 AcrAB efflux pump임을 간접적으로 보여주고 있다. 또한 MarB는 MarA와 함께 대장균의 다른 efflux system(들)의 항생제 배출기능에 대해서도 억제적으로 조절할 가능성이 높은 것으로 나타났다.

• 한국가축번식학회지
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• 제16권4호
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• pp.325-333
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• 1993

A competitive type immunoassay method for 17$\beta$-estradiol(E2) based on the idiotypic anti-idiotypic antibody and time-resolved fluorescence is described. The anti-idiotypic antibody(Ab2) produced to E2 binding site of the primary idiotype antibody (Ab1) was labelled with europium and was allowed to compete with E2 standards or serum sample for the binding sites of Ab1 which was bound to 2nd antibody captured ontothe surface of microtitre plates. Fluorescence measured by time-resolved fluorometer was inversely proportional to the concentration of E2 over the range 5~500pg/well. The sensitivity of the assay was 5pg per well which was compatible with that ofradioimmunoassay using the same Ab1 and 3H-E2 as a tracer. One great advantage of this method described here was to enable antibodies to be labelled instead of haptens, and thus makes it easier to develop sensitive and robust immunoassay systems specially for haptens.

• 한국임상수의학회지
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• 제27권5호
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• pp.501-507
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• 2010

본 연구는 국내 타일레리아에서 주요항원단백질(major surface protein) 유전자의 다양성을 분석해 보고자 수행되었다. 나아가 Msp 유전자의 다양성과 타일레리아의 병원성과의 관계도 분석하였다. 제주에 있는 목장으로부터 총 177마리의 한우 혈액을 공시재료로 사용하여 혈액검사와 18S rRNA를 표적으로 하는 PCR을 실행하였다. 그 후, 타일레리아 18S rRNA에 양성인 28마리 (16마리 빈혈군과 12마리의 정상군)를 무작위로 선발하여 Msp유전자의 염기 서열을 반복하여 분석하였다. 총 56개의 염기서열 결과는 다변성 부위(517-571 bp)에 따라 크게 type I에서 type V까지 5가지 형태로 나눌 수 있었는데, 이는 유전자은행(GenBank)에 등록되어 있는 다음의 유전자와 98.9% 이상 일치하였다 (Theileria spp. from China-EU584237; T. sergenti from China-DQ078264; Theileria spp. from Thailand-AB081329; Theileria spp. from Japan-AB218442; T. sergenti from Japan-AB016280). 그 분포는 22, 15, 9, 8, 2개가 각각 type I에서 V까지 분포하였고 빈혈과 관계없이 type I이 가장 많이 나타나는 것으로 밝혀졌다(37.5%의 빈혈군과 41.7%의 정상군). 나머지 type중에서는 type II가 빈혈군에서 가장 많이(37.5%) 나타났으며, 반면 type IV는 정상군에서 많이 (25%) 나타났다. 본 연구는 국내 타일레리아 Msp유전자의 다양성을 밝히는데 좋은 자료로 활용될 수 있을 것이다.

• 한국세라믹학회지
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• 제45권5호
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• pp.290-296
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• 2008

$AB'_{0.5}B"_{0.5}O_3$ type complex perovskite structures which have been reported as proton conductors over $600^{\circ}C$ were studied. The $AB'_{0.5}B"_{0.5}O_3$ type complex perovskite structure is known to be more easily synthesized and has better stability than normal $ABO_3$ perovskite structure. And it is stable at about $800^{\circ}C$ in the $CO_2$ atmosphere, whereas the $BaCeO_3$ perovskite is easily decomposed into carbonate. In addition, this $AB'_{0.5}B"_{0.5}O_3$ type complex perovskite structure could simply produce oxygen vacancies within their structure not by introducing additional doping oxides but by just controling the molar ratio of $B'^{+3}$ and $B"^{+5}$ metal ions in the B site. Hence it is easy to design the structure which shows highly sensitive electrical conductivity to humidity. In this study, the single phase boundary of $BaR_{0.5+x}Ta_{0.5-x}O_{3-{\delta}}$(R = rare earth) complex perovskite structures and it's phase stability were investigated with changes in composition, x. And the humidity dependance of electrical conductivity at different $P_{H2O}$ conditions was investigated.