• Journal of Plant Biology
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• 제15권3호
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• pp.9-13
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• 1972

This report deals with lead and zinc contamination of roadside soil and plants caused by motor vehicles as a function of distance from the road edge. The concentrations of Pb and Zn in roadside soil and plant samples from several locations decrease regularly with increasing distance from traffic. Soil samples up to 24m distance from the road edge are contaminated with more than 12.99ppm lead, and 13.40ppm zinc. The decrease in Pb and Zn contamination with increasing distance from the road is characteristically curvilinear; the relative coefficiency of Pb and Zn with distance is -0.69, -0.48, respectively. The average contents of Pb and Zn in plants are 21.5ppm and 30.00ppm. It is suggested that the contamination is related to the composition of gasoline, motor oil and to roadside of the residues of this metals.

• 약학회지
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• 제43권1호
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• pp.98-103
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• 1999

Effects of Astragali Radix extract (AG) on the cell mediated-and nonlpecific immunotoxic responses of zinc chloride (Zn) were studied usign ICR mice. Mice were divided into 4 groups (10 mice/group), and Zn was given to the mice 1 hr after i.p. injection with 0.5g/kg of AG by i.p. injection daily for 10 days at a dose of 25 mg/kg. Immune responses on the responses on the relative weight of thymus, delayed-type hypersensitivity to SRBC (DTH), phagocytic activity and circulating leukocytes were evaluated. Zn treatment decreased body weight gain, the relative weight of thymus, DTH and circulating leukocytes compared with those in controls. AG treatment increased DTH, phagocytic activity and circulating leukocytes compared with those in controls. Combination of AG and Zn increased DTH and circulating leukocytes compared with those in controls, but decreased body weight gain and the relative weight of thymus. These findings indicated that AG decreased immunotoxicity of Zn on the DTH and circulating leukocytes.

• 상하수도학회지
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• 제13권1호
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• pp.134-139
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• 1999

This study was conducted to determine the effects of water aggressivity on the corrosion in a recirculating pipe loop systems. As the pH was increased in the range of pH 6.0~8.5, water aggressivity was decreased. Zine and iron concentration of water adjusted by pH were lower than those of tap water and water adjusted by alkalinity and calcium hardness. The major elements of corrosion deposit analyzed by EDS(Energy Dispersion Spectrophotometer) were zinc and calcium. In conclusion, we suggest that in corrosion control practice in the water works industry, increasing the pH of the water can serve as a way of controlling the solubility of metal ions release from water distribution systems.

• 한국표면공학회지
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• 제30권2호
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• pp.128-135
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• 1997

The effect of the polyethyledglycol(PEG) on the surface morphology and crystal orientation of electrodeposited zinc from a chloride (1.5M Zinc+7.0M chloriode) have been studied by means of electrochemical methodes, scanning electron microscopy, surface appearance measurement and X-ray diffraction patterns. The resistance of electrodeposit increased, whereas the evolution of hydrogen decreased with incrasing of molecular weight of the PEG. Large grains of electrodeposit were obtained from bath in the absence of organid additive. When the PEG was added, fine grained crystals were observed and the surface roughness was relatively small, but surface appearance deteriorated. The preferred orientation with a(101) plane parallel to the surface was obtained from the PEG addited bath.

• Bulletin of the Korean Chemical Society
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• 제21권10호
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• pp.1052-1054
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• 2000

Binding geometries of $[Ru(II)(110-phenanthroline)_2L]^2+$, complexes (where L = dipyrido [3,2-a:2',3'-c]phena-zine (DPPZ) or benzodipyrido[3,2-a:2',3'-c] phenazine (BDPPZ)) to poly(dG)${\cdot}$poly(dC)${\cdot}$poly(dC) + triplex DNA (CGC + triplex) has been investigated by linear dichroism and normal absorption spectroscopy. Analysis of the linear dichroism for the CGC+ triplex and $[Ru(II)(phen)_2BDPPZ]^2+$ complex indicates that the extended ligand of the metal complex lie perpendicular to the polynucleotide helix axis. Together with strong hypochromism and red shift in the interligand absorption region, we concluded that the extended BDPPZ or DPPZ ligand in-tercalated between the bases of polynucleotide. The spectral properties of the metal complexes bound to CGC+ triplex are similar to those bound to $poly(dA)[poly(dT)]^2$ triplex (Choi et al., Biochemistry 1997, 36, 214), sug-gesting that the metal complex is located in the minor groove of the CGC+ triplex.

• Advances in concrete construction
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• 제8권3호
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• pp.199-206
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• 2019

High performance sandcretes (HPS) are new concretes characterized by particles having a diameter less than 5 mm, as well as very high mechanical strength and durability. This work consists in finding solutions to make sandcretes with good physico-mechanical and durability properties for this new generation of micro-concrete. However, upgrading ordinary sandcrete into high performance sandcrete (HPS) requires a thorough study of formulation parameters (equivalent water/binder ratio, type of cement and its dosage, kind and amount of super plasticizer, and gravel/sand ratio). This research study concerns the formulation, characterization and durability, in a sulphate environment, of a high performance sandcrete (HPS), made from local materials. The obtained results show that the rheological properties of fresh concrete and mechanical strength differ with the mineralogy, density and grain size distribution of sands and silica fume used.

• 한국비블리아학회지
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• 제33권3호
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• pp.267-293
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• 2022

웹진은 기관 구성원과 이용자 사이의 커뮤니케이션 역할을 담당할 뿐만 아니라 그 자체가 하나의 의미 있는 기록물이라고 할 수 있다. 또한 기록관의 경영기법 중 하나로 서비스를 홍보하고 잠재적 이용자들이 기록관을 찾게 하는 적극적 마케팅이 필요하다는 인식이 확산되고 있다. 따라서 웹진을 설계함에 있어서 이용자의 수요를 파악한 뒤 이를 반영한 콘텐츠를 구성하고 이용자 중심의 인터페이스를 적절하게 선택함으로써 이용자의 만족도를 높이는 노력이 필요하다. 따라서 본 연구는 스마트 디바이스 환경에서 대통령기록관 소식지인 '온기(On-記)'를 이용자 참여형 스마트 플랫폼으로 설계하는 것을 제안하고자 하였다. 이를 위하여 국내 유관기관의 웹진 발행 현황을 살펴보고 나아가 대통령기록관에서 제공하고 있는 '온기'의 발행사항과 주요 콘텐츠를 비교 분석하여 대통령기록관 마케팅을 위한 웹진의 설계 모형을 제안하였다. 이는 스마트 디바이스의 기술 혁신이라는 새로운 이용자 환경에서 대통령기록관의 핵심 마케팅 전략으로 활용할 수 있다.

• 분석과학
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• 제14권4호
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• pp.324-330
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• 2001

마이크로파 분해법과 유도결합 플라스마 원자방출분광법(ICP-AES)을 이용하여 윤활유내의 S, P와 Zn의 분석을 하였다. 윤활유는 질산 또는 질산-과산화수소의 혼합산을 분해용액으로 하여 밀폐형 마이크로파 분해장치로 분해시켰다. 기존의 분해방법과 비교하여 펄스 방식에 의해 작동되어지는 단계적인 가열 프로그램은 윤활유 매질을 안전하게 분해하는데 3~4배 빠르고 효율적이었다. 제의된 분해방법은 검출된 원소들에 대해 3% 미만의 상대표준편차(RSD)를 보여주었다.

• 한국결정성장학회지
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• 제8권4호
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• pp.592-598
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• 1998

ZnO($Al_2O_3\;2%$ 2% doped) 산화물 타겟과 금속 Zn(Al 2% doped) 타겟을 사용하여 반응성 직류 마그네트론 스퍼터링법으로 산소 가스 및 인가 전력을 조절하면서 AZO(Aluminum doped Zine Oxide) 막을 증착하였다. 비저항과 평균 투과율을 고려할 때 최적의 투명전도성을 보이는 조건은 산화물 타겟의 경우 산소가스의 비가 $0.5{\times}10^{-2}~1.0{\times}10^{-2}$범위이며, 금속 타겟의 경우 인가전력 0.6kW에서는 0.215~0.227, 1.0kW에서는 0.305~0.315이었다. 각 최적조건에서 제막된 AZO 막의 비저항은 $1.2~1.4{\times}10^{-3} {\Omega}{\cdot}cm$cm으로 타겟에 의한 차이는 없었다.

• The Korean Journal of Ecology
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• 제20권1호
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• pp.51-59
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• 1997

To investigate the distribution of heavy metal concentrations in Onsan bay, concentrations of cadmium, copper, zine and lead in surface sediments and the periwinkles (Littorina brevicula) were determined in Feburary and July, 1996. The ranges of cadmium, copper, zinc and lead concentrations in the surface sediments were 0.08-3.72, 3-307, 49-1273 and 15-399 ${\mu}g/g$ dry weight, respectively, The decrease of concentration in heavy metals with distance from Daejeong stream indicated that this stream is the pollutant source of heavy metals in Onsan Bay. The concentrations of cadmium, copper, zinc and led in L. brevicula were 0.11-11.81, 21-212, 30-96 and 0.26-4.12 ${\mu}g/g$ dry weigth in February and 1.01-24.9, 66-325, 54-225 and 0.68-8.41 ${\mu}g/g$ dry weight in July, respectively. These concentrations in L. brevicula were the significantly different (p<0.001) with the season of sampling. However, overall distribution of concentrations of heavy metals in L. brevicula had very similar tendency that concentrations of heavy metal decreased with the distance from the pollutant source irrespective of the two seasons. Therefore, L. brevicula is considered as a useful indicator for heavy metals pollution, According to analysis of the organs, tissues such as the digestive gland, gill and viceral mussel accumulate high concentrations of heavy metals.