• Bulletin of the Korean Chemical Society
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• 제21권10호
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• pp.969-972
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• 2000

[Fe II Fe III $BPLNP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)ami-no)methyl]-4-nitrophenol (HBPLNP) . Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electrochemical methods. Complex 1 exhibits two strong bands at 498 nm $(\varepsilon=$ 2.6 ${\times}10^3M-^1cm-^1)$ and 1363 nm $(\varepsilon=$ 5.7 ${\times}10^2M-^1cm-^1)$ in $CH_3CN.$ These are assigned to phenolate-to-FeIII and intervalence charge-transfer transitions, respectively. NMR spectrum of complex 1 exhibits sharp isotropically shifted resonances, which number is half of those expected for a valence-trapped species, indicating that electron transfer between FeⅡ and FeⅢ centers is faster than NMR time scale at room temperature. Complex 1 undergoes quasireversible one-electron redox processes. The $FeIII_2/FeIIFeIII$ and $FeIIFeIII/FeII_2$ redox couples are at 0.807 and 0.167 V ver-sus SCE, respectively. It has Kcomp = 5.9 ${\times}$10 1s(acetato) ligand combination sta-bilizes a mixed-valence FeIIFeIII complex in the air. Interestingly, complex 1 exhibits intense EPR signals at g = 8.56, 5.45, 4.30 corresponding to mononuclear high-spin FeⅢ species, which suggest a very weak magnetic coupling between the iron centers. Magnetic susceptibility study shows that there is a very weak antiferromag-netic coupling (J = $-0.78cm-^1$, H = $-2JS_1${\times}$S_2)$ between FeII and FeIII centers. Thus, we can suggest that complex 1 has a very weak antiferromagnetic coupling between the iron centers due to the electronic effect of the nitro group in the bridging phenolate ligand.

• 생태와환경
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• 제47권3호
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• pp.135-145
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• 2014

오대산 국립공원 계방산(해발고도 1,577 m) 일대의 산지삼림식생은 산지낙엽활엽수림, 산지습성림, 산지침엽수림, 아고산침엽수림, 아고산활엽수림, 식재림으로 세분되었으며, 기타식생으로 다래군락, 농경지 등이 조사되었다. 상관대분류에 의하여 구분된 각각의 산지삼림식생을 구성하고 있는 분포군락수는 산지낙엽활엽수림은 33개 군락, 산지습성림 41개 군락, 산지침엽수림 8개 군락, 아고산침엽수림 4개 군락, 아고산활엽수림 2개 군락, 식재림 6개 군락, 기타식생 4개 군락이 조사되었다. 조사된 주요 군락의 분포 비율을 보면 산지낙엽활엽수림은 신갈나무군락이 $30,909,942.967m^2$의 80.220%로 가장 높은 분포 비율로 조사되었고, 굴참나무군락이 $1,067,479.335m^2$의 2.770%를 차지하고 있으며, 계방산 일대 산지낙엽활엽수림의 65.755%는 신갈나무가 우점 또는 차우점종으로 분포하고 있다. 산지습성림은 물푸레나무-가래나무군락이 전체의 10.955%를 차지하고 있으며, 물푸레나무와 상층부의 식피율이 비슷하여 혼생군락을 이루고 있는 군락은 10개 군락으로 전체의 32.776%를 차지하고 있다. 산지침엽수림은 소나무와 이와 혼생하는 군락이 전체의 100%로서 산지침염수림은 소나무가 상층부에서 우점종으로 나타나는 군락의 양상을 나타내고 있다. 기타식생에서 아고산침엽수림은 전나무-신갈나무군락 등 총 4개 군락이 조사되었으며 오대산 국립공원 전체 식생면적의 4.980%를 차지하고 있다. 아고산 활엽수립은 사스래나무-층층나무군락 등 총 2개 군락이 조사되었으며 오대산 국립공원 전체 식생면적의 0.006%를 차지하고 있다. 식재림은 일본잎갈나무가 식재림 전체의 51.652%로 가장 많이 식재되었으며, 자작나무가 38.975%, 잣나무가 7.969%로 3개 수종이 전체의 98.565%로 대부분이 이들 3종에 의하여 식재되어졌다. 결론적으로 오대산 국립공원 계방산 일대의 산림식생은 신갈나무가 최상층부의 우점종으로 구성되어 있으며, 이들 종들과 관련된 수많은 군락들은 식생천이 및 기후적 요인들에 의하여 군락 대체가 매우 빠르게 일어날 것으로 보인다. 따라서 이 지역 일대 잠재 자연 식생의 주요종은 산지낙엽활엽수림은 신갈나무, 산지습성림은 가래나무, 들메나무, 산지낙엽활엽수림은 신갈나무, 산지습성림은 물푸레나무, 가래나무, 들메나무, 산지낙엽활엽수림과 산지습성림의 경계부 중 습도가 높은 계곡부는 층층나무, 들메나무, 사면부는 신갈나무로 대체가 빠르게 일어날 것으로 보인다. 그러나 아고산의 침염수림은 기후온난화, 인위적 교란 등에 의하여 점차적으로 낙엽 활엽수의 분포비율이 증가할 것으로 보인다.

• 한국환경생태학회지
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• 제26권3호
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• pp.382-393
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• 2012

경상북도 문경 희양산 산림식생 특성을 봉암사 산림유전자원보호구역을 중심으로 파악하였다. 총 92개 조사구($100m^2/plot$)에 대한 조사를 실시하고, Classification 분석과 Ordination 분석을 통해 군락분류를 실시한 결과 이 지역의 식생은 신갈나무군락, 굴참나무군락, 소나무군락, 소나무-졸참나무군락, 소나무-신갈나무군락, 졸참나무군락, 낙엽활엽수군락, 잣나무조림지, 일본잎갈나무조림지의 총 9개 군락으로 분류되었다. 각 군락간의 비교를 위해 지형조건과 식생조사 결과에 대한 통계분석을 실시하였으며, 해발고도, 경사, 출현종수, 교목층 출현 개체수, 아교목층 출현 개체수에서 통계적으로 유의하게 군락간 차이를 보였다. 층위별 상대우점치를 통한 각 군락의 군락구조를 분석한 결과, 참나무류군락은 교목층과 아교목층에 고르게 세력을 형성하고 있어 현재의 군락이 유지되거나 확대될 것으로 예상되는 반면, 소나무 우점 군락은 대부분 참나무류와의 경쟁이 심화되고 있어 향후 이들 참나무류로의 천이가 예상되었다.

• 생명과학회지
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• 제17권7호통권87호
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• pp.882-888
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• 2007

전분 젤 전기영동을 사용하여 한국내 분포하는 동자개 여섯 집단에서 유전적 다양성과 집단구조를 평가하였다. 14개 대립유전자좌위에서 9좌위가 다형현상을 나타내었다(64.3%). 종수준과 집단수준에서 유전적 다양성은 각각 0.286과 0.277이였다. Wright의 고정지수에서 Hardy-Weinberg 평형에 비해 전반적인 이형접합체 결핍이 나타났다. 이 결핍은 집단내 유효한 개체수의 부족을 시사한다. 집단간 유전적 분화 정도는 0.064로 대부분의 유전적 변이(93.6%)가 집단내에 있음을 의미한다. 간접적으로 평가된 집단간 이주하는 개체수는 3.67로 나타났다. 제한된 유전자 유동과 유효집단의 감소는 유전적 부동을 유발하고, 주기적인 포획으로 인한 개체수의 감소는 유전자 상실로 이어지고 있다. 대부분의 집단이 겨울철 가뭄과 여름철 홍수로 심한 병목을 겪고 있었다.

• Applied Microscopy
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• 제47권3호
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• pp.148-156
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• 2017

The wide distribution of redox-sensitive elements (RSE) as arsenic (As), cadmium (Cd), selenium (Se), and strontium (Sr) in the top soil of Siwaqa area are related to the weathering action of alkaline surface and groundwater on the parent rocks. The bioavailability, distribution, sorption, and ecotoxicity of As, Cd, Se, and Sr, of the wild plants and top soils in the study area were investigated. A total number of 23 surface soil samples and 23 plant samples were collected and analyzed for the most toxic elements. The uptake of elements by plants was dependent on the plant species and the concentration of elements in the soil. For example, Sr was the highest concentration in soil samples and plants, while Se was the lowest concentration in soil samples and pants. For the plants, the results showed that Bellevalia sp. had the highest elements uptake, while Allium rothii had the lowest elements uptake. The results of this work provide a valuable knowledge for understanding the bioavailability of some toxic elements in the soil and plants of Central Jordan. The results are expected to be of great help for the Jordanian Uranium Mining Company during their environmental risk assessments.

• 수산해양기술연구
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• 제49권4호
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• pp.341-351
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• 2013

Physical characteristics of PA (Polyamide) gill net and biodegradable gill net made by PBS (Polybutylene succinate) (mesh size 63mm, mesh thickness number 2, 2.5, 3) were analyzed to investigate catching efficiency of the biodegradable gill net for Pacific herring. Total 11 numbers of catching efficiency tests were carried out using commercial fishing vessel at Imwon port in Kangwon province from May to June 2013. The amount of catches were 1,535.7kg (18 species) through the catching efficiency tests and it is expected that the practicalization of biodegradable gillnet is possible because there is no difference for catches between PA gillnet and PBS gillnet. Catches of herring according to the thickness of net twine was the highest at No.2 and the thicker net twine tends to decrease the catches.

• 제어로봇시스템학회논문지
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• 제9권12호
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• pp.1042-1047
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• 2003

The goal of this research is to implement a PC-based remote control system of ion implanter using Visual Basic programming. Presently, skilled process engineers are required to regularly setup and adjust implanter parameters. Any reduction in the number of production hours devoted to ion beam implanter setup or recalibration after a species change would represent substantial improvements in both manpower and equipment utilization. An optical communication system for the remote control and telemetry in the operation of the 50kev potential was designed and constructed. This system enables continuous and safe operation of the ion implanter and can be the basis for the automation. The isolation characteristics of optical fiber were 10kV/cm, and performance tests of the system under the intense noise environment during the implanter operations showed satisfactory results. This system is designed to completely replace the existing human-machine interface with many new functions. This paper describes the important components of the system including system architecture and software development. It is expected that this system can be used for the communication and control purpose in the high noise environments such as the operation of the MeV energy implanter or other high power, high noise systems.

• Fisheries and Aquatic Sciences
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• 제16권4호
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• pp.303-309
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• 2013

Microsatellite markers are important for gene mapping and for marker-assisted selection. Sixty-five polymorphic microsatellite markers were developed with an enriched partial genomic library from olive flounder Paralichthys olivaceus an important commercial fish species in Korea. The variability of these markers was tested in 30 individuals collected from the East Sea (Korea). The number of alleles for each locus ranged from 2 to 33 (mean, 17.1). Observed and expected heterozygosity as well as polymorphism information content varied from 0.313 to 1.000 (mean, 0.788), from 0.323 to 0.977 (mean, 0.820), and from 0.277 to 0.960 (mean, 0.787), respectively. Nine loci showed significant deviation from the Hardy-Weinberg equilibrium after sequential Bonferroni correction. Analysis with MICROCHECKER suggested the presence of null alleles at five of these loci with estimated null allele frequencies of 0.126-0.285. These new microsatellite markers from genomic libraries will be useful for constructing a P. olivaceus linkage map.

• 한국환경복원기술학회지
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• 제16권6호
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• pp.31-48
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• 2013

South Korea had encouraged farmers to breed bear to increase farmer's income since 1981. Currently farmers breed over thousand number of bears, however but the policy measures for breeding bears is expected to conflict the main stream of bear conservation due to South Korea belong to the member of CITES, which categorizes and manages bears under Wild Fauna and Flora Protection Act. Government needs to establish a special law containg the win-win relief strategy not only for farmers of breeding bears, but international corresponding policy. So, we have reviewed the domestic status and international trends on breeding bears, and suggest the alternative strategies of the policy such as a bear park, a bear village, use of species recovery center, use of a preservation organization. This policy should be accompanied with more detailed fact analysis, management agency, well equipped welfare facility and financial preparation for proper management of breeding bears against changing international trends on wildlife conservation.

• Journal of Plant Biology
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• 제38권4호
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• pp.329-336
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• 1995

Raphanus sativus L. var. hortensis f. raphanistroides (wild radish: Brassicaceae), a herbaceous perennial, occurs only on beaches in East Asia. Genetic diversity and population structure of seven Korean populations were investigated using starch gel electrophoresis. Although the Korean populatins are small, isolated with patchy distribution, the population maintain a moderate level of genetic diversity; the mean percentage fo polymorphic loci was 51.4%, mean number of alleles per locus was 1.84, and mean expected heterozygosity was 0.116. A combination of animal-outcrossing breeding system, wide geographical distribution, restricted ecological distribution, and a propensity for high fecundity may in part be explanatory factors contributing the moderate level of genetic diversity within populations. An overall excess of homozygotes relative to Hardy-Weinberg expetations (mean FISa=0.116) indicates that consanguineous mating occur within wild radish populations, leading to a family structure within a circumscribed area. Although population of wild radish experience a limited gene flow, only 5% of the total genetic variation found in Korean wild radish populations examined is due to differences among populations (mean GST=0.052). This value is considerably lower than the mean values of species with similar life history and ecological characteristics. However, significant differences were found in allele frequencies between populations for all polymorphic loci (P<0.01). It is supposed that directional selection toward genetic uniformity (similar gene frequencies) in a relatively homogenous habitat is thought to be operated among Korean wild radish populations.