• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.29.2-29.2
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• 2009

21세기 제 3의 산업혁명을 가져올 것으로 기대되는 나노기술(NT), 정보기술(IT), 바이오기술(BT)은 전 세계 과학자들의 마음을 사로잡고 있다. 이 가운데 나노기술은 전자산업에 응용 시 그 기대효과는 우리가 상상하는 이상의 것이라 예상하고 있다. 나노기술에 특히 관심을 가지는 이유는 물질이 마이크로미터 크기로 작아져도 벌크물질의 물리적 특성이 그대로 유지되지만, 나노미터 크기가 되면서 우리가 경험하지 못했던 새로운 물리적 특성들이 발현되기 때문이다. 그 특성에는 양자구속효과, Hall-Petch 효과, 자기효과 등이 있다. 나노기술의 구현은 양자점과 같은 영차원 나노입자, 나노와이어, 나노막대, 나노리본 등과 같은 직경이 100nm 이하의 일차원 구조의 나노물질 및 나노박막과 기타 100nm 이하의 나노구조물들이 사용된다. 현재 일차원 구조를 이용한 전자디바이스화 연구는 결정성장을 정확하게 조절하는 합성기술, 합성된 일차원 나노물질의 물리적 특성을 지배하는 각종 파라미터들과 물리적 특성들과의 상관관계 정립, 나노와이어를 이용한 Bottom-up 방식에 의한 조립기술 확보를 위해 활발히 진행 중이다. 하지만 나노구조의 특성을 확인하는 형태의 연구일 뿐, 실제 디바이스 구현에는 여전히 많은 과제를 안고 있다. 본 연구에서는 선택적 삼원계 단결정 씨앗층을 이용한 길이/직경 비가 매우 향상된 MgZnO 나노와이어를 interfacial layer 없이 수직으로 성장하여 산화물 전계방출 에미터로서의 가능성을 확인하였다.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.313-319
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• 2007

The nutritional medium requirement for biosurfactant production by Bacillus licheniformis K51 was optimized. The important medium components, identified by the initial screening method of Plackett-Burman, were $H_3PO_4,\;CaCl_2,H_3BO_3$, and Na-EDTA. Box-Behnken response surface methodology was applied to further optimize biosurfactant production. The optimal concentrations for higher production of biosurfactants were (g/l): glucose, $1.1;NaNO_3,\;4.4;MgSO_4{\cdot}7H_2O,\;0.8;KCl,\;0.4;CaCl_2,\;0.27;H_3PO_4,\;1.0ml/l;\;and\;trace elements\;(mg/l):H_3BO_3,\;0.25;CuSO_4,\;0.6;MnSO_4,\;2.2;Na_{2}MoO_4,\;0.5;ZnSO_4,\;6.0;FeSO_4,\;8.0;CoCL_2,\;1.0;$ and Na-EDTA, 30.0. Using this statistical optimization method, the relative biosurfactant yield as critical micelle dilution (CMD) was increased from $10{\times}\;to\;105{\times}$, which is ten times higher than the non-optimized rich medium.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.561-568
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• 2009

We determined the contents of heavy metals in the muscle of wild and cultured fishes, collected from fish markets located in the eastern (Pohang), western (Gunsan), and southern (Tongyeong) coasts of Korea, from 2004 to 2005. As the results of monitoring the heavy metal contents in spring season, the wild fishes contained the range of Cd (0.01-0.08 mg/kg), Cr (ND-0.28 mg/kg), Cu (0.06-1.53 mg/kg), Hg (0.02-0.16 mg/kg), Mn (0.04-1.15 mg/kg), Ni (ND-0.09 mg/kg), Pb (0.03-0.41 mg/kg), and Zn (1.84-6.61 mg/kg). While for the cultured fishes, Cd (0.01-0.05 mg/kg), Cr (ND-0.17 mg/kg), Cu (0.05-0.61 mg/kg), Hg (0.02-0.13 mg/kg), Mn (0.03-0.17 mg/kg), Ni (ND-0.08 mg/kg), Pb (0.03-0.33 mg/kg), and Zn (2.06-6.20 mg/kg) were contained. In summer season, the contents of heavy metal in the muscle of the wild fishes were as follows: Cd (ND-0.11 mg/kg), Cr (0.01-0.37 mg/kg), Cu (0.21-1.31 mg/kg), Hg (0.01-0.11 mg/kg), Mn (ND-1.47 mg/kg), Ni (ND-0.26 mg/kg), Pb (0.06-0.48 mg/kg), and Zn (2.94-14.38 mg/kg). In comparison, the contents of heavy metal in the muscle of cultured fishes were Cd (ND-0.05 mg/kg), Cr (0.13-0.33 mg/kg), Cu (0.19-0.56 mg/kg), Hg (0.05-0.26 mg/kg), Mn (ND-0.14 mg/kg), Ni (ND-0.58 mg/kg), Pb (0.07-0.45 mg/kg), and Zn (2.43-7.53 mg/kg). Also the fall and the winter season, the heavy metal contents in the fishes showed almost similar with other season, however, Pb was lower and Zn was higher than both spring and summer season. The wild fishes contained the heavy metals a little more than the cultured fishes. We could not observe clear seasonal variation in the heavy metal contents of the fishes. The levels of Hg and Pb in all samples tested did not exceed the maximum permissible levels in the fishes set by the Korean Food & Drug Agency for safe human consumption.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.1
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• pp.51-69
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• 2000

This dissertation was to research how some metal level within SipJeonDaeBo - Decoction, one of oriental prescriptions, influence Sprague-Dawley animals. 1. Under the experiment with drinking waters there was no metal ${\sim}0.65\;mg/L$ detected. A metal with feed found 0.001-376.983mg/kg. 2. In the mice's kidney, brain, bones used experiment, As searched 0.474 mg/kg, 0.486 mg/kg, 0.314 mg/kg 0.834 mg/kg respectively ; Cd 0.060 mg/kg, 0.045 mg/kg, 0.030 mg/kg, 0.353 mg/kg, ; Co 0.105 mg/kg, 0.063 mg/kg, 0.030 mg/kg, 0.399 mg/kg, ; Cr 0.292 mg/kg, 0.304 mg/kg, 0.234 mg/kg, 0.962 mg/kg, ; Cu 4.201 mg/kg, 3.759 mg/kg, 1.923 mg/kg, 0.484 mg/kg, ; Fe 57.535 mg/kg, 150.571 mg/kg, 17.178 mg/kg, 281.506 mg/kg, ; no Hg, Mn 0.612 mg/kg, 2.968 mg/kg, 0.528 mg/kg, 4.205 mg/kg, ; Ni 0.094 mg/kg, 0.072 mg/kg, 0.078 mg/kg, 27.714 mg/kg, ; Pb 0.269 mg/kg, 0.293 mg/kg, 0.283 mg/kg, 43.142 mg/kg ; Zn 4.149 mg/kg, 21.861 mg/kg, 8.088 mg/kg, 226.283 mg/kg respectively. 3. In level of hazardous metal within idney control group searched 0.194 {\pm}\; 0.052 mg/kg, experimental I g개up $0.189{\pm}0.036\;mg/kg$, experimental I group $0.264 {\pm}{\pm}\;0.179\;mg/kg$. In level of non hazardous metal control group searched $15.917{\pm}5.575\;mg/kg$, experiment I group $17.064{\pm}2.246\;mg/kg$, experiment II group $16.892{\pm}3.586\;mg/kg$. Besides in total level of metal control g.cup detected $6.484{\pm}2.258\;mg/kg$, experiment I group $6.940{\pm}0.914\;mg/kg$, experiment II group $6.915{\pm} 1.508\;mg/kg$ There all was no statistical significance. 4. In level of hazardous metal within the liver control group searched $0.187{\pm}0.048\;mg/kg$, experiment I g개up $0.168[\pm}0.079\;mg/kg$, experiment II group $0.277{\pm}0.159\;mg/kg$. In level of non hazardous heavy metal control group detected $44.925{\pm}18.468\;mg/kg$, experiment I group $39.917{\pm}12.772\;mg/kg$, experiment II group $49.525{\pm}33.484\;mg/kg$. Besides in total concentration control group searched $18.082{\pm}7.395\;mg/kg$, experiment I group $16.068{\pm}5.128\;mg/kg$, experiment II group $19.977{\pm}13.443\;mg/kg$. There was no statistical significance but hazardous metal gets more level in the experilnent group than in the control group. 5. In level of hazardous metal within brain control group searched $0.145{\pm}0.056\;mg/kg$, experiment I group $$0.167{\pm}0.030\;mg/kg, erperiment II group $0.172{\pm}0.123\;mg/kg$. In level of non hazardous heavy metal control group detected $6.488{\pm}0.965\;mg/kg$, experiment I group $7.290{\pm}0.588\;mg/kg$, experiment II group $7.010{\pm}1.627\;mg/kg$. Besides in total concentration control group searched $2.683{\pm}7.395\;mg/kg$, experiment I group $3.017{\pm}0.238\;mg/kg$, experiment II group $2.908 {\pm} 0.711\;mg/kg$. Therefore there was no statistical significance. 6. In level of hazardous metal within bone control group searched $8.172{\pm}5.195 \;mg/kg$, experiment I group $9.128{\pm}4.143\;mg/kg$, experiment II group $9.401{\pm}6.924\;mg/kg$. There is statistical significance(p<0.05). In level of non hazardous metal control group detected $94.065{\pm}36.035\;mg/kg$, experiment I group $147.563 {\pm}79.939\;mg/kg$, experiment II group $142.730{\pm}77.374\;mg/kg$. Besides in total level control group searched $48.530{\pm}16.523\;mg/kg$, experiment I group $64.502{\pm}31.078\;mg/kg$, experiment II group $62.733 {\pm}34.641\;mg/kg$. Therefore there was no statistical significance. 7 In the correlative research as to how each metal influences to ingestion Cd and Co searched 0.954 and Pb and Ni -0.0884 from kidney. Co and Cd was 0.995 and Zn and As -0.190 from liver. Co and Cd were 0.995 and Zn and Cu -0.393 from brain. Co and Cd were 0.998 and Zn and Mn -0.206 from bones

• Applied Biological Chemistry
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• v.30 no.1
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• pp.77-87
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• 1987

The mutant with high productivity, X. malvacearum SNUF 560-6, was acquired from the X. malvacearum SNUF 560 with low productivity by UV-light irradiation. It was preserved is lyophilized stock culture and it was transferred to PDA slant to maintain viability fortnightly. Fermentations were started by retransfering to MY agar slant from PDA stok culture. The experiments for optimal xanthan gum production were studied in a chemically defined medium. Of the carbon and nitrogen sources tested, 0.4% sucrose medium and 10mM glutamic acid medium yielded the highest xanthan gun production respectively. The addition of 10g/l succinic acid stimulated xanthan gum production. Also 65mM $PO_4\;^{-3}\;(12.6g/l\;KH_2PO_4)$ was effective on xanthan gum production. Finally, medium 1 and medium 2 which have high xanthan gum production potencies were achieved in this stud. The components of medium 1 and medium 2 were as follows: Medium 1 : sucrose 40g/l glutamate 10mM $PO_4\;^{-3}\;54mM\;(KH_2PO_4\;12.65g/l)$ Citrate 2g/l $MgSO_4{\cdot}7H_2O\;0.2g/l$ $H_3BO_3\;0.005/l$ ZnO 0.006/l $FeCl_2{\cdot}6H_2O\;0.0024g/l$ $CaCO_3\;0.02g/l$ Medium 2 : $Sucrose\;40g/l\;(NH_4)_2SO_4\;2g/l$ $PO_4\;^{-3}\;65mM\;(KH_2PO_4\;12.65g/l)$ Succinate 10g/l $MgSO_4{\cdot}7H_2O\;0.02g/l$ $H_3BO_3\;0.06g/l$ ZnO 0.006g/l $FeCl_2{\cdot}6H_2O\;0.0024g/l$ $CaCO_3\;0.02g/l$.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2008.04a
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• pp.127-130
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• 2008

• Journal of the Korean Applied Science and Technology
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• v.26 no.4
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• pp.440-450
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• 2009

Metal(Zinc) soap and mixed metal(Zn/Ba) soap were synthesized with good structures and characterized by IR and H-NMR. The H-NMR spectrums of the synthesized soaps were in very good accordance with the structures proposed by earlier workers. The mixed metal soaps with various costabilizers(acid or metal content effect), which added in order to investigate the thermal stabilization effect at low and high temperature, were investigated the thermal stabilization effect. The temperature effect is relation to the metal content effect than acid effect. In case of mixed metal soap, the high thermal stabilization effect improved with increasing Barium content. As the Zinc content increase the low temperature thermal stabilization effect improved, but the high temperature thermal stabilization effect showed an opposite tendency.

• Analytical Science and Technology
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• v.23 no.6
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• pp.615-618
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• 2010

An oxygen bomb combustion procedure were studied for determination of heavy metal in polymer materials such as polyvinyl chloride and polypropylene by ICP-AES. This method is proposed as a rapid and simple sample preparation for decomposition of polymer containing certified contents of the analytes by teflon coated oxygen bomb combustion using different absorbing solution. The recoveries of metal were found to be 30~102% from absorbed solution by ICP-AES method using polypropylene certified reference material(PP CRM-As, Ba, Cd, Hg, Pb, Zn). The recoveries of metal using PVC CRM(Cd, Hg, Pb) was found to be 45 ~101% with same procedures.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.1
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• pp.56-60
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• 2016

Benzyltrimethylammonium dichloroiodate in the presence of $ZnCl_2$ has been used for aromatic iodination of electron rich aromatic compounds. However, Baylis-Hillman type regioselective ${\alpha}$-iodination was carried out electronically rich coumarin compound under mild reaction condition with excellent chemical yield. Finally, $BBr_3$ demethylation gave ${\alpha}$-iododaphnetin.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.2
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• pp.93-103
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• 2009

To measure the mineral contents of marine invertebrates, we collected 239 individuals from 52 species from the east (Pohang), west (Gunsan), and south (Tongyeong) coasts of Korea: 34 species of molluscan shellfish (Gastropoda and Bivalvia), 6 species of Cephalopoda, 8 species of Crustacea, and 4 other species. The mean contents of the macro mineral in the 100g edible portion of molluscan shellfish were high in the oder of Na (355.1 mg), P (128.1 mg), K (110.8 mg), Mg (83.8 mg) and Ca (57.5 mg). And the mean contents of the micro mineral in the molluscan shellfish were high in the oder of Fe ($41.12{\mu}g/g$), Zn ($30.48{\mu}g/g$), Mn ($3.81{\mu}g/g$), Cu ($3.49{\mu}g/g$) and Ni ($0.35{\mu}g/g$). We could not observe clear regional variation in the mineral content of the molluscan shellfish species. The mean contents of the macro mineral in the 100g edible portion of other marine invertebrates (Cephalopoda, Crustacea, etc.) were high in the oder of Na (400.7 mg), P (145.1 mg), K (105.0 mg), Mg (63.2 mg) and Ca (49.0 mg). And the mean contents of the micro mineral in other marine invertebrates were high in the oder of Zn ($24.4{\mu}g/g$), Fe ($13.8{\mu}g/g$), Cu ($4.88{\mu}g/g$), Mn ($2.14{\mu}g/g$) and Ni ($0.12{\mu}g/g$). The daily average intakes of the macro mineral through fisheries products consisted of P (125.9 mg), Na (119.3 mg), K (101.8 mg), Ca (31.0 mg), Mg (27.6 mg). And the daily average intakes of the micro mineral through fisheries products consisted of Zn (0.92 mg), Fe (0.68 mg), Cu (0.12 mg) and Mn (0.07 mg). The respective intakes of the minerals (P, Mg, Na, Ca, K) from fish were about 18.0, 7.9, 8.0, 4.4 and 2.2% of the dietary reference intakes for Koreans (KDRIs) set by the Korean Nutrition Society. And the respective intakes of micro mineral (Cu, Zn, Fe, Mn) from fish were about 14.6, 9.2, 6.7, and 2.1% of the dietary reference intakes for Koreans (KDRIs). Therefore, fisheries products play a very important role as a source of mineral.