• 한국환경보건학회지
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• 제19권1호
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• pp.44-50
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• 1993

In order to investigate the hygienic conditions of potable water in farm area, we examined the hygienic bacteriological and chemical tests of the 159 waters in the farm areas of Kwangjugun, Namyangju-gun, Yangpyung-gun Paju-gun and Hwasung-gun.The results were as follows: 1. Of the 159 waters, the average numbers of standard plate count and coliform were 920 $\pm$ 250ml and 450 $\pm$ 380/100 ml, respectively. The average pH was 6.74 $\pm$ 0.08, KMnO$_4$ consumption 4.18 $\pm$ 0.23 mg/l, turbidity 0.74 $\pm$ 0.08 degree, NH$_3$-N 0.07 $\pm$ 0.02 mg/l, NO$_3$-N 7.76 $\pm$ 0.48 mg/l, total hardness 101.3 $\pm$ 4.7mg/l, chlorine 18.6 $\pm$ 1.3mg/l, sulfate 12.9 $\pm$ 1.0 mg/l, lead 0.036 $\pm$ 0.003 mg/l, manganese 0.017 $\pm$ 0.003 mg/l, zinc 0.064 $\pm$ 0.005 mg/l, and copper 0.010 $\pm$ 0.001 mg/l, respectively. 2. Of the 159 waters, 84 samples (52.8%) were over 100 per ml of SPC or detected coliform per 100 ml water and 63 samples (39.6%) exceed over physicochemical limited criteria for potable water. NO$_3$-N was the primary item among excess contents of potable water in farm areas. 3. The contents of total hardness, chlorine and NO$_3$-N in Hwasung-gun were higher than those in the other regions, but the numbers of SPC and coliform in Yangpyung-gun and Namyangjugun were higher than those in the other regions. 4. The correlationships among many items were highly significant (SPC, Coliform, KMnO$_4$ consumption NH$_4$-N, NO$_3$-N, KMnO$_4$, Total hardness, Chlorine, Sulfate).

• Asian-Australasian Journal of Animal Sciences
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• 제22권12호
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• pp.1648-1653
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• 2009

This experiment was designed to evaluate the effects of source of supplemental zinc (Zn) on performance, nutrient digestibility and plasma mineral profile in Cashmere goats during the cashmere fiber growing period. Twenty-seven Liao Ning Cashmere wether goats (9-10 month of age; initial BW = 19.31${\pm}$0.32 kg) were fed a basal diet (containing 22.3 mg Zn/kg DM) with no supplemental Zn (control) or 20 mg of supplemental Zn/kg of DM from Zn sulfate ($ZnSO_{4}$) or Zn methionine (ZnMet) for 60 days including a 10-day metabolism trial. Average daily gain (ADG) (p<0.05) and gain:feed (G/F) (p<0.05) were increased by Zn supplementation, but no differences were noted between Zn sources (p>0.05). The length and diameter of cashmere fiber did not differ among treatments (p>0.05). Zn supplementation had no influence on digestibility of DM, CP, EE and NDF (p>0.05). However, ADF digestibility in the group supplemented with ZnMet was significantly higher than in other treatments (p<0.05). Plasma Zn was increased (p<0.05) and Cu tended to be decreased (p = 0.057) by Zn supplementation, but no differences were found between Zn sources (p>0.05). Plasma alkaline phosphatase activity (AKP) was improved by Zn supplementation (p<0.05) and was higher in the $ZnSO_{4}$ than the ZnMet group (p<0.05). Zn retention was increased (p<0.05) and apparent absorption rate was decreased (p<0.05) by Zn supplementation. The results indicate that supplementation of 20 mg Zn/kg DM either as $ZnSO_{4}$ or ZnMet in the basal diet containing 22.3 mg Zn/kg DM can improve growth performance in Cashmere goats, and effectiveness of the two sources is similar on performance measurements.

• 한국환경보건학회지
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• 제20권1호
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• pp.62-67
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• 1994

ZnO-$Fe_2O_3$ 복합금속 산화물 흡착제가 황화수소 제거능이나 황화된 흡착제의 산화적 재생반응에 미치는 영향을 고찰하였다. Zinc ferrite 흡착제가 가장 높은 황화수소 제거능을 나타내었고 혼합한 $Fe_2O_3$ 흡착제는 황화반응 도중 H$_2$S의 생성을 촉진시킴을 알 수 있었다. 또한 황화반응의 결과로 생성되는 금속황화물들이 H$_2$S 열분해의 촉매로 작용하였으며 H$_2$는 $Fe_2O_3$의 함량이 증가할수록 더 많이 발생하였다. 산화적 재생반응의 결과로부터 ZnS를 제외하고 $Fe_2O_3$를 혼합한 흡착제는 모두 잘 재생됨을 알 수 있었다. 또한 산화적 재생반응 도중 생성될 수 있다고 보고된 zinc sulfate는 생성되지 않았다. 그리고 SO$_2$ 발생 곡선의 형태나 완전재생에 소요되는 시간을 기준으로 판단해 볼 때 $Fe_2O_3$의 혼합량의 변화는 산화적 재생반응에 별다른 영향을 미치지 않음을 알 수 있었다.

• 한국동물위생학회지
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• 제31권4호
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• pp.505-519
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• 2008

For screening the appropriate field diagnostic techniques to failure of passive immunoglobulin transfer(FPT) in Korean-indigenous calves, 258 sera was examined by spectinophotometry for total protein(TP) and globulin(Glo), sodium sulfate precipitation test(SSPT), zinc sulfate turbidity test(ZSTT), and single radial immunodiffusion test(sRID). All calves aged within 6-week old. Morbidity and mortality to various diseases, mainly including enteric and respiratory disorders, were 18.9%(49) and 4.2%(11), respectively. FPT was 27,9%(72/258) when the cutoff point of TP was $4.5g/d{\ell}$ and among them the morbidity and mortality were 27.9% and 6.9%, respectively. FPT was 29.1%(75/258) when the cutoff point of Glo was $2.0g/d{\ell}$ and among them the morbidity and mortality were 29.0% and 6.9%, respectively. FPT was 13.1%(34/258) when the cutoff point of SSPT was 1+ and among them the morbidity and mortality were 67.6% and 23.5%, respectively. FPT was 19.7%(51/258) when the cutoff point of IgG with sRID was $1,000mg/d{\ell}$ and among them the morbidity and mortality were 41.1% and 11.7%, respectively. In addition, mean concentration of IgG with sRID tested was $2,150mg/d{\ell}$ at 3-day old but $1,100mg/d{\ell}$ at 9-days with $1,100mg/d{\ell}$. The results of the study were suggested that SSPT for FPT was the relatively reliable and convinient method for evaluating the immune status of calves(P<0.05).

• 한국식품조리과학회지
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• 제20권2호
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• pp.119-125
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• 2004

Mixograph를 이용하여 반죽의 물성에 미치는 화학첨가제의 영향을 조사한 결과 ammonium ferric citrate와 ferric sulfate는 0.1% 수준에서는 밀가루 반죽의 탄성에 뚜렷한 영향을 미치지 않았으나, MgSO$_4$, CaCl$_2$ 및 ZnO는 반죽의 탄성을 증가시키며 최적반죽시간을 연장시켜 반죽 시간이 길어졌다. 그러나 Ca과 Mg을 각각 갖는 calcium citrate와 MgCl$_2$는 반죽 시간이나 탄성에 뚜렷한 영향을 나타내지 않았다. 빵의 부피에 미치는 영향은 0.1% MgSO$_4$와 CaCl$_2$가 브롬산 칼륨을 전혀 첨가하지 않은 대조구보다 부피 팽창이 더 커져서 브롬산 칼륨과 같은 팽창제로서의 기능을 확인하였으며, 이들을 첨가한 빵의 속과 겉껍질의 색은 모두 대조구보다 더 밝아서 첨가한 화학첨가제들이 빵의 색을 밝게 하는 것을 확인할 수 있었다. 밀가루의 내재된 효소를 불활성화 시키기 위하여 볶음처리와 UV 및 microwave 조사된 밀가루는 최적 반죽시간을 초과하여 계속 반죽하여도 최적반죽시간 후 반죽의 탄성저하현상이 처리하지 않은 대조구에 비하여 감소되어 반죽의 안정성이 향상되었으나, 열처리한 밀가루로 제조한 빵은 부피가 대조구에 비하여 적었으므로 열처리는 반죽의 안정성은 향상시킬 수는 있으나 빵의 부피 증가에는 효과적이지 못하였다.

• 대한약침학회지
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• 제14권2호
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• pp.5-14
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• 2011

Objectives: Fibrinolytic enzyme preparations were isolated from the snake venom of Macrovipera lebetica turanica in this study. Methods: The purity of the preparations was determined using SDS-PAGE and the enzymic characteristics of the purified fibrinolytic enzyme were determined. Results: 1. All of the two preparations with fibrinolytic activity obtained from the snake venom of M. l. turanicat contained the major polypeptide with the molecular weight of 27,500. One of the preparation showed purified fibrinolytic enzyme. 2. The purified fibrinolytic enzyme hydrolyzed ${\alpha}$-chain of fibrinogen faster than ${\beta}$-chain but not ${\gamma}$-chain. 3. The fibrinolytic activity was inhibited completely by EDTA, EGTA, 1,10-phenanthroline, and dithiothreitol. 4. The fibrinolytic activity was inhibited completely by calcium chloride, iron(III) chloride, mercuric chloride, and cobalt (II) chloride. 5. The fibrinolysis zone formed after addition of zinc sulfate was smaller but clearer than the control. Conclusions: These results suggested that the fibrinolytic enzyme purifed from the snake venom of M. l turanica was a metalloprotease containing dithiol group.

• BMB Reports
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• 제30권1호
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• pp.60-65
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• 1997

Expression of human Cu.Zn-superoxide dismutase (SOD) with activity comparable to human erythrocyte enzyme was achieved in E. coli B21(DE3) by using the pET-17b expression vector containing a T7 promoter. Recombinant human SOD was found in the cytosol of disrupted bacterial cells and represented > 25% of the total bacterial proteins. The protein produced by the E. coli cells was purified using a combination of ammonium sulfate precipitation, Sephacryl S-100 gel filtration and DEAE-Sephacel ion exchange chromatography. The recombinant Cu,Zn-SOD and human erythrocyte enzyme were compared using dismutation activity, SDS-PAGE and immunoblotting analysis. The mass of the subunits was determined to be 15,809 by using a electrospray mass spectrometer. The copper specific chelator. diethyldithiocarbamate (DOC) reacted with the recombinant Cu,Zn-SOD. At $50{\mu}M$ and $100{\mu}M$ concentrations of DOC, the dismutation activity was not inhibited for one hour but gradually reduced after one hour. This result suggests that the reaction of DOC with the enzyme occurred in two distinct phases (phase I and phase II). During phase I of this reaction, one DOC reacted with the copper center, with retention of the dismutation activity while the second DOC displaced the copper, with a loss of activity in phase II.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.193-197
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• 2001

This study was carried out to recover gold, silver and other valuable metals from the printed circuit boards (PCB) of waste computers. PCB samples were crushed to under 1mm by a shredder and initially separated into 30% conducting and 70% non-conducting materials by an electrostatic separator. The conducting materials, which contained the valuable metals, were then used as the feed material for magnetic separation where it was found that 42% was magnetic and 58% non- magnetic. The non-magnetic materials contained 0.227mg/g Au and 0.697mg/g Ag. Further leaching of the non-magnetic component using 2.0M sulfuric acid and 0.2M hydrogen peroxide at 85$^{\circ}C$ extracted more than 95% copper, iron, zinc, nickel and aluminium. Au and Ag were not extracted in this solution, however, more than 95% of Au and 100% of Ag were selectively leached with a mixed solvent (0.2M ammonium thiosulfate, 0.02M copper sulfate, 0.4M ammonium hydroxide). Finally, the residues were reacted with a NaCl solution to leach out Pb while sulfuric acid was used to leach out Sn. Recoveries reached 95% and 98% in solution, respectively.

• 에너지공학
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• 제25권4호
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• pp.245-250
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• 2016

이산화망간은 전지의 활성물질로서 우수한 특성을 가지고 있고 가격도 저렴한 재료로서 각종 1차전지에 사용되어왔다. 그러나 이산화망간을 이용한 2차 전지에 대한 연구는 그렇게 많지 않다. 최근 이산화망간의 충전가역성에 관하여 황산아연을 전해질로 하는 이산화망간 아연전지가 재충전이 가능하다는 보고가 있다. 여기서는 이산화망간이 황산아연수용액 중에서 가역적으로 충전방전이 가능한 것을 토대로 2차전지로서의 가능성에 대해 서술한다.

• Tribology and Lubricants
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• 제10권4호
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• pp.43-50
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• 1994

In order to elucidate the effects of co-existing additives (S$_{8}$, TBP: Tri butyl phosphate, ZnDTP: Zinc-dialkyl dithiophosphate) and the role of reacted surface film on the friction behavior of MoDTP (molybdenum dialkyl dithiophosphate), a friction experiment using a dual circular pipe edge surface type friction tester and XPS (X-ray photoelectronic spectrum) surface analysis were conducted. Friction reduction with MoDTP lubricant was proved to be greatly influenced by co-existing additive species. It was dependent on the properties of the film formed through the reaction between the additive and the surface. Phosphate film reduced the friction coefficient of MoDTP through suppression of diffusion of Mo compounds towards the metal substrate. On the other hand, sulfate film, which is inherently rich in lattice defects, did not lead to any appreciable friction reduction with MoDTP since the diffusion of the Mo compound towards the metal substrate was not effectively suppressed. With ZnDTP additive, the sulfide film formed through decomposition greatly influenced the lubricating performance of MoDTP. As such, properties of surface films formed from additives were proved to yield significant influence on the lubrication performance of MoDTP.