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        검색결과 512

        121.
        2013.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This study investigated the continuous cooling transformation, microstructure, and mechanical properties of highstrength low-alloy steels containing B and Cu. Continuous cooling transformation diagrams under non-deformed and deformed conditions were constructed by means of dilatometry, metallographic methods, and hardness data. Based on the continuous cooling transformation behaviors, six kinds of steel specimens with different B and Cu contents were fabricated by a thermomechanical control process comprising controlled rolling and accelerated cooling. Then, tensile and Charpy impact tests were conducted to examine the correlation of the microstructure with mechanical properties. Deformation in the austenite region promoted the formation of quasi-polygonal ferrite and granular bainite with a significant increase in transformation start temperatures. The mechanical test results indicate that the B-added steel specimens had higher strength and lower upper-shelf energy than the B-free steel specimens without deterioration in low-temperature toughness because their microstructures were mostly composed of lower bainite and lath martensite with a small amount of degenerate upper bainite. On the other hand, the increase of Cu content from 0.5 wt.% to 1.5 wt.% noticeably increased yield and tensile strengths by 100 MPa without loss of ductility, which may be attributed to the enhanced solid solution hardening and precipitation hardening resulting from veryfine Cu precipitates formed during accelerated cooling.
        4,000원
        122.
        2013.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The structural phase transformations of 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-0.3PT) were studied using high resolution x-ray diffraction (HRXRD) as a function of temperature and electric field. A phase transformational sequence of cubic (C)→tetragonal (T)→rhombohedral (R) phase was observed in zero-field-cooled conditions; and a C→T→monoclinic (Mc)→ monoclinic (MA) phase was observed in the field-cooled conditions. The transformation of T to MA phase was realized through an intermediate Mc phase. The results also represent conclusive and direct evidence of a Mc to MA phase transformation in field-cooled conditions. Beginning from the zero-field-cooled condition, a R→MA→Mc→T phase transformational sequence was found with an increasing electric field at a fixed temperature. Upon removal of the field, the MA phase was stable at room temperature. With increasing the field, the transformation temperature from T to Mc and from Mc to MA phase decreased, and the phase stability ranges of both T and Mc phases increased. Upon removal of the field, the phase transformation from R to MA phase was irreversible, but from MA to Mc was reversible, which means that MA is the dominant phase under the electric field. In the M phase region, the results confirmed that lattice parameters and tilt angles were weakly temperature dependent over the range of investigated temperatures.
        4,000원
        123.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Abstract This manuscript reports on compared color evolution about phase transformation of α-FeOOH@SiO2 and β-FeOOH@SiO2 pigments. Prepared α-FeOOH and β-FeOOH were coated with silica for enhancing thermal properties and coloration of both samples. To study phase and color of α-FeOOH and β-FeOOH, we prepared nano sized iron oxide hydroxide pigments which were coated with SiO2 using tetraethylorthosilicate and cetyltrimethyl-ammonium bro- mide as a surface modifier. The silica-coated both samples were calcined at high temperatures (300, 700 and 1000°C) and characterized by scanning electron microscopy, CIE L*a*b* color parameter measurements, transmission electron microscopy and UV-vis spectroscopy. The yellow α-FeOOH and β-FeOOH was transformed to α-Fe2O3 with red, brown at 300, 700°C, respectively.
        4,000원
        124.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This manuscript reports on compared color evolution about phase transformation of α-FeOOH@SiO2 and β-FeOOH@SiO2 pigments. Prepared α-FeOOH and β-FeOOH were coated with silica for enhancing thermal properties and coloration of both samples. To study phase and color of α-FeOOH and β-FeOOH, we prepared nano sized iron oxide hydroxide pigments which were coated with SiO2 using tetraethylorthosilicate and cetyltrimethyl-ammonium bro- mide as a surface modifier. The silica-coated both samples were calcined at high temperatures (300, 700 and 1000°C) and characterized by scanning electron microscopy, CIE L*a*b* color parameter measurements, transmission electron microscopy and UV-vis spectroscopy. The yellow α-FeOOH and β-FeOOH was transformed to α-Fe2O3 with red, brown at 300, 700°C, respectively.
        4,000원
        125.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        포장에서 생육된 잔디 포복경을 이용한 Agrobacterium 형질전환에 있어서 큰 제한인자였던 곰팡이 오염을 제거할목적으로 포복경 조직에 대한 새로운 살균법을 개발하고자하였다. 여러 가지 살균방법 중에서 30% NaOCl로 15분간처리한 다음 0.1% HgCl2로 25분간 처리 했을 때 포복경절편체의 생존율이 높았으며, 0.1% HgCl2로 처리시 800mbar의 진공처리를 5분간 실시했을 때 가장 효과적이었다.또한 Agrobacterium과 공동배양 시 2.5 mg/l의 amphotericinB를 첨가해 준 배지에서 배양했을 때 가장 높은 생존율을나타내었다. AmB의 처리는 Agrobacterium의 생장에 영향을 미치지 않았다. 또한 살균된 포복경으로 부터 신초의재분화에도 영향을 미치지 않았으며 곰팡이 오염만을 효율적으로 억제하는 것으로 나타났다. 이러한 결과는 포장에서 대량으로 생육시킨 잔디 포복경을 이용한 Agrobacterium형질전환 시 그 효율을 증가시키는데 큰 기여를 할 것으로추측된다.
        4,000원
        126.
        2013.06 구독 인증기관 무료, 개인회원 유료
        Aluminum oxide 지지체를 사용하여 루테늄 촉매가 개발되었고, 이 루테늄 촉매는 수중에서 일차 아민또는 니트릴을 기질로 하여 일차 아미드 합성에 적용되었다. 방향족, 비활성화 된 지방족, 환 모양의 헤테로 원자 등의 다양한 기질들의 아민 또는 니트릴이 최종 생산물인 일차 아미드로 높은 수율을 보이며전환되었다. 그리고 이 반응들에서 산 또는 염기와 같은 첨가물이나 일반적인 산화제 등의 도움없이 반응이 수중에서 진행되었다. 사용된 촉매는불균일 촉매임이 분명하였고, 그 촉매는 단순여과에 의해metal-leaching 없이 회수되었으며, 회수된 촉매는 촉매 성능의 변화없이 여러 번 재사용되었다.
        4,000원
        127.
        2013.05 구독 인증기관 무료, 개인회원 유료
        The object of this thesis is to study the Urban Hanoks around Cheongryangri district. Cheongryangri district became one of Seoul’s administrative districts due to the expansion of the urban area. It is located on the east side of Dongdaemun, the development was to deal with the lack of residential houses in the city. This research was to specify the stylistic characteristics of Urban Hanok in Cheongryangri area by analyzing the changes in residential Urban Hanok for to the influence the market. First, Cheongnyangni Urban Hanok shows the changes in the configuration of plan in accordance with change of the purpose and the way household are divided. Second, as the function of Urban Hanok changed there has been changes in cross-section area. Third, Urban Hanoks with different function have different location. Fourth, the functional change in shops does not cause the change in the plan.
        4,000원
        128.
        2013.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        동하중을 고려하는 구조해석은 전산자원과 시간측면에서 상당한 어려움이 따르기 때문에 외력을 이상적인 정하중으로 가정하는 것이 일반적이다. 그러나 정하중 조건으로 해석된 결과는 구조물의 안전설계 측면에서 충분한 신뢰를 주기 어렵다. 최근에는, 동하중의 영향을 받는 구조물의 효과적인 구조해석을 위해 동하중을 등가정하중으로 변환하는 기법이 제안되어 왔다. 이 기법은 최적화를 통해 구속조건을 만족하는 최소의 등가정하중을 구하는데, 구속조건은 임계시간의 변위를 사용하고, 등가정하중 분포 자유도는 경험적으로 선정하여 왔다. 그러나 안전설계 관점에서는 응력 구속조건을 적용하는 것이 타당하며, 경험적 자유도 선정은 몇 개의 자유도에 과도한 하중이 부과되거나 구조물의 거동에 영향력이 없는 자유도들이 선정될 가능성이 있다. 본 연구에서는 등가응력 구속조건을 고려하는 등가정하중 최적화 방법을 제안하고, 축소시스템 개념을 도입한 주자유도, 구속조건 요소 자유도, 외부하중 자유도로 구성되는 등가정하중 분포 자유도의 구성방법을 제안한다. 수치예제에서는 제안된 방법으로 구해진 등가정하중을 사용하여 등가응력을 구하고 동하중 해석 결과와 비교함으로써 제안된 방법을 통한 구조해석 방법이 구조안전성 측면에서 타당함을 보인다.
        4,000원
        129.
        2013.04 구독 인증기관·개인회원 무료
        Entomopathogenic fungus, Beauveria bassiana can be used in integrated crop management and pharmaceutical applications. Recently some efforts have been given to the fungus to improve its biological performances, but low fungal transformation efficiency is one of the limitations. In this work, B. bassiana ERL1170 isolate was used for fungal transformation by restriction enzyme-mediated integration, where pBARKS1-Bbs-cecropinA was linearied using HindIII. The fungal transformation comprised two steps, preparation of competent blastospores and integration of the plasmid into the cells. To prepare competent blastospores, 2-d cultured blastospores were individually treated with 0.1, 0.2, 0.4 and 0.8 M lithium acetate (LiAc). Secondly in the integration step, concentration of LiAc and calcium chloride (CaCl2), and time period of heat shock were investigated as follows: LiAc, 1, 2 and 4 M; CaCl2, 50, 100 and 200 mM; and heat shock at 42℃, 20, 40 and 60 min. Consequently, combination of 0.2 M LiAc in preparing competent blastospores and 2 M LiAc and 200 mM CaCl2 in the second step showed the highest transformation efficiency. This work would be helpful in the fungal transformation of B. bassiana.
        130.
        2013.04 구독 인증기관·개인회원 무료
        we exist in the relations with others. The concepts of interpersonal relationships most base on the person in this relationship, that is the whole point of life who come from people's lives. The value of lives lies in the communicated activity, it reflects substantive sense of human beings. Harmonious interpersonal relationship is the final appeal for interpersonal relationship. The question is how the ethical appeals formed in the context of traditional relationships? What is its effect on our modern life, and how the value of thought in modern society changed. 1.Chinese traditional culture is the one of" Agriculture - patriarchal "social ethical culture who grown in soil. This kind of culture is the Isomorphism of home and farm economy, its has always worked every Chinese and have a far-reaching impact on all aspects of our daily lives. Judging from the Social communication standard of Anthropology, the interpersonal boundaries were divided from the start of the 'family'. We use the concept of caste and blood formed and maintained the community, then the interactions must based on the core of family. That decided our interactions has the character of closing from beginning, on this basis, the Chinese strongly agreed with the concept of clan and family psychology. On the premise of a common ancestor, everyone has grown within the community, and we call 'insiders', the opposite of' outsiders 'requirements of living is a directly reflect for family of interpersonal ethics, this is the major cause of promoting harmonious interpersonal relations. In addition, from the religious faith , the Chinese reverence for nature and'harmony between the heaven and human', the concept of 'Harmony' are another important cause of harmonious relations. The concept of harmonious order was imitated the natural state of harmony and the family should follow this way. It can explain the consistency of the Chinese concept in the universe and human relations leading to inherent unity and harmony. Z. What the community need is a major cause of the traditional interpersonal harmony. In fact it is a social inherent requirements, and the consistency of traditional view of the universe and human relations is the requirements of unification from society and nature, Both of these are based on the phylogenetic relationships and blood relationship. With the development of productive forces and the scale, genealogical community gradually extend the production activities scope to adjust production relations through other ways. In the process, the genealogical community transfered to unrelated community transformation, communication ethics are becoming increasingly complicated. From a geopolitical perspective, the transformation of the ancient family from blood to unrelated blood, is occured in the basic areas of the country. Early in the Qin dynasty, Han Dynasty, the social economic assistance functions appeared more intensively. these kinds of rural family economic assistance organizations enhanced cohesion between the different families of the same country , And then it extended to the different country. But expand the scope of contacts between the two villages still relatively weak. that formed more narrow and less - developed interpersonal style who accompanied by an acquaintance of Village Community Associationin ancient China. So we say the interpersonal harmony is not purely relations and exchanges, because the traditional Confucian thought we should learn and be taught everywhere in interpersonal relationships, so that the ethics would appear everywhere. Ethical relationships of the family should not be arrogated, and also the Confucian Ethics, were implanted in social relations, this made it possible to achieve the ideal of a harmonious society. We need the deep thoughts to modern ways of communication and thinking now. At the same time we should drawn nutrition from the roots of Chinese Traditional Thought of harmonious interpersonal relationship in order to seek the path of our modern society's interpersonal relationships. From " primary internal requirement " to "mutual requirements", we should establish a " Principle of CO-exist in the communication" in this kind of relationship, the premise of Co-exist is an independent individual. because on this premise, every independent individual access to maximal benefits, each individual must rely on the ourselves cooperation. from above reasoning, we can see that the only way of modern harmonious interpersonal relationships is the " CO-exist in principle ".
        131.
        2013.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        BCAP 유전자를 지니는 pRB374-BCAP2와 pLip-BCAP2를 B. clausii I-52에 도입 후, 염색체 integration에 의해 구성된 pHPS9-BCAP 형질전환체(B. clausii C5)와 alkaline protease 발현율을 비교하였다. 최적화 배지(대두박 2%, 밀가루 1%, 구연산나트륨 0.5%, K2HPO4 0.4%, Na2HPO4 0.1%, NaCl 0.4%, MgSO4⋅7H2O 0.01%, FeSO4⋅7H2O 0.05%, 물엿 2.5%, 탄산나트륨 0.6%)에서 액침배양(37℃, 48 h, 650 rpm, 1 vvm) 시, pRB374- BCAP2 및 pHPS9-BCAP 형질전환체 각각은 15% 및 61% 정도 alkaline protease 생산이 증가하였다. 그러나 pLip-BCAP2 형질전환체에서는 변화가 없었다. 최고의 활성 균주인, B. clausii C5를 300 L 규모 pilot-scale 액침 배양(37℃, 30 h, 250 rpm, 1 vvm) 시, alkaline protease 생산은 105,685 U/mL로 측정되었다.
        4,000원
        132.
        2013.01 구독 인증기관 무료, 개인회원 유료
        자연적으로 일어나는 형질전환은 세균에서 유전 요소의 수평적 전달 메커니즘의 하나로서 세균 생리학에서 빠질 수 없을 만큼 중요한 현상이다. S. thermophilus는 자연적으로 형질전환이 가능한 상태로 변환하기 위해서 Rgg-타입의 response regulator인 ComR과 소수성 펩타이드 페르몬인 ComS를 포함하는 새로운 quorum sencing 시스템을 이용한다. S. thermophilus를 화학적 제한배지에서 배양하면 대수기 초기에 신호서열이 분리된 ComS는 세포외부로 배출된다. 배출된 ComS는 올리고 펩타이드 전달 시스템인 Ami를 통하여 세포내로 유입되어 ComR과 결합하게 된다. ComS와 결합된 활성화된 ComR은 후기 형질전환 관련 유전자들의 전사를 조절하는 대체형 시그마펙터(σx)를 암호화하는 comX 유전자의 발현을 유도함으로써 형질전환이 일어나도록 만든다. 신호서열이 제거된 ComS를 합성하여 화학적 합성배지에 첨가하게 되면, S. thermophilus의 형질전환을 인공적으로 유도할 수 있다. Leuconostoc 속 유산균들 은 그들이 후기 형질전환 관련 유전자들과 서열이 유사한 단백질 유전자들을 보유하고 있음에도 불구하고 자연적 형질전환 메커니즘은 아직 밝혀지지 않았다. Leuconostoc 속의 자연적 형질전환의 메커니즘을 규명하는 연구는 김치산업에서 사용될 수 있는 개량된 균주 개발을 가능하게 할 것이다.
        4,000원
        133.
        2012.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We investigate the role of galaxy environment in the evolution of individual galaxies through the AKARI observations of the merging galaxy cluster A2255. MIR diagnostics using N3-S11 colors are adopted to select star-forming galaxies and galaxies in transition between star-forming galaxies and quiescent galaxies. We do not find particular enhancement of star formation rates as a function of galaxy environment, reflected in cluster-centric distance and local surface density of galaxies. Instead, the locations of intermediate MIR-excess galaxies (-1.2 < N3 - S11 < 0.2) show that star-forming galaxies are transformed into passive galaxies in the substructures of A2255, where the local surface density of galaxies is relatively high.
        3,000원
        135.
        2012.08 구독 인증기관·개인회원 무료
        In the process of using Chinese characters, there are appearances that semantic of characters used in context are different from the glyphs. The chinese writing system makes use of the ideographic elastic category to adjustoriginalpictophonetic characters and maintains effectively its own ideographic features.
        136.
        2012.07 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        The dielectric properties and phase transformation of poled <001>-oriented Pb(Mg1/3Nb2/3)O3-x%PbTiO3(PMN-x%PT) single crystals with compositions of x=20, 30, and 35mole% are investigated for orientations both parallel andperpendicular to the [001] poling direction. An electric-field-induced monoclinic phase was observed for the initial poled PMN-30PT and PMN-35PT samples by means of high-resolution synchrotron x-ray diffraction. The monoclinic phase appears from−25oC to 100oC and from −25oC to 80oC for the PMN-30PT and PMN-35PT samples, respectively. The dielectric constant (ε)-temperature (T) characteristics above the Curie temperature were found to be described by the equation(1/ε−1/εm)1/n=(T−Tm)/C, where εm is the maximum dielectric constant and Tm is the temperature giving εm, and n and C are constants that changewith the composition. The value of n was found to be 1.82 and 1.38 for 20PT and 35PT, respectively. The results of meshscans and the temperature-dependence of the dielectric constant demonstrate that the initial monoclinic phase changes to a singledomain tetragonal phase and a to paraelectric cubic phase. In the ferroelectric tetragonal phase with a single domain state, thedielectric constant measured perpendicular to the poling direction was dramatically higher than that measured in the paralleldirection. A large dielectric constant implies easier polarization rotation away from the polar axis. This enhancement is believedto be related to dielectric softening close to the morphotropic phase boundary.
        3,000원
        138.
        2012.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aims to classify the architectural formation of the Stylobate of and Staircase types of Post-Lintel Construction in Backje style and Silla style and also to figure out their specific elements by periods and transformation characteristics. The scope of this study was restricted to architectural remains between the Three Kingdom period and the Goryeo period. To progress the investigation, the study classified remains in a similar type by period and type, and then and analyzed its character based on formation method and specific factors of subsidiary materials. As a result, its type can be classified as Backje type(Ⅰ), Silla type(Ⅱ) and Mixed type(Ⅲ). Regionally, it is found that Woongjin, Sabi and surroundings in the capital of Backje, Gyeongju and main towns in the capital of Silla, and Gaeseong and main towns in the capital of Goryeo. In particular, type III has the characteristics of type I and II simultaneously, which has one or two layers Jangdaeseok stone between the foundation stone of stylobate and plate stone, and tends to be decorative when Taengjuseok stone is installed. For types of staircase, it could be classified as 6~7C Backje type(Ⅰ), 7~9C Silla type(Ⅱ) and 9C Mixed type(Ⅲ) according to the formation method of Somaetdol (banister of stone stair). And from the 9th century on, decorated Somaetdol stone type(IV) of 1/4 circle shape began to appear. The common feature of stylobate of post-lintel and staircase is that it became simplified, abbreviated and decorative. It seems to be intended to secure simplicity of construction or structural stability.
        5,500원
        139.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Trichoderma harzianum 균사체를 Al2O3 입자와 마찰시킴으로써 Agrobacterium을 이용한 형질전환 에 효과적으로 이용할 수 있었다. Hygromycin 저항성 균사체 출현을 비교한 결과 형질전환 효율이 20% 정도로 나타났으며 대조군의 경우 형질전환균사체의 출현은 없었다. 2차례의 연속적인 항생제배지에서 선발을 거친 형질전환균사체들은 PCR에 의하여 안정적 DNA도입이 확인되었으며 RT-PCR에 의하여 target gene의 mRNA발현을 확인할 수 있었다. 현재까지 Agrobacterium을 이용한 T. harzianum 형질 전환은 보고된 바 없다.
        4,000원
        140.
        2011.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Gene manipulation of Siberian wildrye grass through transgenic technology can modify grass feature for further improvement in the forage production. In order to optimize transformation conditions of Siberian wildrye grass, the effects of transformation efficiency was investigated with GUS gene. Seed-derived calli were infected and co-cultured with Agrobacterium tumefaciens carrying the binary vector pCAMBIA3301 encoding the GUS gene in the T-DNA region. The effects of several factors on transformation and the expression of the GUS gene were investigated. The highest transformation efficiency was obtained when embryogenic calli were inoculated with Agrobacterium strain EHA101 in the presence of 200 μM acetosyringone and coculture for 5 days. The present study was framed and materialized to standardize an efficient, high frequency and reproducible genetic transformation protocol for aromatic Siberian wildrye grass using Agrobacterium tumefaciens.
        4,000원