• Korean Journal of Crystallography
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• v.16 no.1
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• pp.38-42
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• 2005

The crystal structure of Bis(ethylenediamine) cuprate(II)$\cdot$dichromate, $Cu(C_2H_8N_2)_2{\cdot}Cr_2O_7$, has been determined by X-ray crystallography. Crystal data: a=5.682(2), b=8.567(3), c=14.839(3) ${\AA},\;{\alpha}=97.50(2),\;{\beta}=101.06(1),\;{\gamma}=109.38(2)^{\circ}$ Triclinic, P-1 (SG No=2), Z=2, V=653.9(2) ${\AA}^3,\;D_c=2.030gcm^{-3},\;{\mu}=3.273mm^{-1}$. The structure was solved by Patterson method and refined by full matrix least-square methods uslng unit weights. The final R and S values were $R_1=0.0256,\;R_w=0.0708,\;R_{all}=0.0316,\;S=1.151$ for the observed 2291 reflections. The two cupper complex ion has the usual distorted octahedral structure with mean four Cu-N distances of 2.010(3) $\AA$ and the longer mean Cu-O distance of 2.525(2) $\AA$. The Cu-complex and dichromate ions are linked to form infinite chain arranged alternatively along the [111]-direction. The neighboring chains in the (0-11) plane are connected with N1-O5 and N3-O1 hydrogen bonds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.9
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• pp.1214-1221
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• 2008

The aim of this study is to propose suggestions for establishing Korean regulatory standards of infant formula. Accordingly, the regulatory standards for food contaminants and additives in Korean infant formulas were compared and analyzed with those in CODEX, EU, Australia and New Zealand. Several suggestions for regulations were found from different countries. Firstly, it is advisable that additives for nutrient supplement of infant formula be classified as types of nutrients. Secondly, it is proposed that guidelines should be set on the maximum amount of additives in infant formula. Thirdly, pathogens such as Staphylococci and Salmonella of infant formula should be regulated. Finally, present regulations need to establish the maximum permissible levels of some pesticides, Pb and Al, that other countries are already regulating. These proposed recommendations would broaden the scope of infant formula regulatory standards needed for infants' health.

• Korean Journal of Ichthyology
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• v.29 no.1
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• pp.41-51
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• 2017

To understand the application in farm for the fish aquaculture, we investigated biological and pathological traits on red sea bream Pagrus major which were reared in each copper-alloy net cage and the synthetic fiber net cage for 9 months. Two groups of cage were made and set in Yokji-eup, Tongyoung, Gyeongsangnam-do in size of 25 m in diameter and 10 m of depth. Survival rate of the red sea bream in the rearing copper-alloy net cage and synthetic fiber cage showed 99.75% and 99.70% respectively, there was no significant difference. Daily weight growth rate in each net was shown to 2.13 g/day and 1.65 g/day. Health analysis by blood composition analysis showed a favorable result in the copper-alloy net cage rather than in the synthetic fiber net. Bioaccumulation of heavy metal such as Cu and Zn especially in gonad was higher than other organ. Bioaccumulation of Cu and Zn in the muscle was lower compared to the permitted standard for food safety. Pathogenic infection test discovered Microcotyle tai for parasite, V. alginolyticus and other five species for bacteria. But there was a little bit difference of bacteria infection in copper-alloy net cage and copper-alloy net cage is expected to be has antibacterial effect. Thus, copper-alloy net cage can be applied to farm considering its system stability, recycling, antibiosis and food safety.

• Clean Technology
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• v.23 no.4
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• pp.364-377
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• 2017

In this study, to improve the low surface area of domestic anthracite as raw materials of activated carbon, characteristics on chemical activation and VOCs adsorption of activated carbon according to mixing ratio of anthracite and lignite. For these, properties of raw materials, parameter characteristics of preparation processes for activated carbon, and VOCs adsorption characteristic of the prepared activated carbon are analyzed. The experimental results showed that, the domestic anthracite had disadvantages of high contents for ash and lead, arsenic, which were exceeded for the heavy metal limits, in the properties of raw materials. To improve these diadvantages, using the mixing ratio of anthracite and lignite, and the optimum conditions for pretreatment, activation, washing, and pellitization process, the activated carbon had a range of BET (Brunauer-Emmett-Teller) surface area of $1,154{\sim}1,420m^2g^{-1}$ with mesopore development and hydrophobic surface property. The carbons were satisfied with the quality standard for granular activated carbon, and had similar physicochemical properties with the commercial activated carbon. The minimum mixing condition for commercial VOCs activated carbon performance must have the caloric value of above $5,640kcal\;kg^{-1}$, and the carbon had higher adsorption capacity with order of xylene > toluene > benzene according to more higher molcular weight and hydrophobic property.

• Applied Chemistry for Engineering
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• v.31 no.4
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• pp.423-428
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• 2020

In this work, we investigated the effect of the concentration of medium components on microbial growth and ethanol production in order to improve ethanol productivity in the Clostridium autoethanogenum culture process using syngas as a sole carbon source. Molybenum, nickel and cobalt (as heavy metal ions) were selected as examined components, and the effects of components concentration on the cell growth and ethanol production was examined. Among molybdenum concentrations of 0, 0.001, 0.01 and 0.1 g/L. a slight increase in ethanol production was observed at 0.001 g/L, but significant differences in the microbial growth and ethanol production were not observed in the examined concentration range. In the case of nickel concentration of 0, 0.001, 0.01 and 0.1 g/L, the change in the microbial growth and ethanol production was investigated, and it was found that the ethanol production using 0.001 g/L increased by 26% compared to that of using the basal medium concentration (0.01g/L). The effect of cobalt concentrations (0, 0.018, 0.18 and 1.8 g/L) on the microbial growth and ethanol production was also investigated, and the inhibition of microbial growth was observed when the cobalt usage was over 0.18 g/L. In conclusion, cobalt did not show any further improvement of ethanol production by changing concentration, however, molybdenum and nickel showed increases in the produced ethanol concentration compared to that of using 1/10 times of the basal medium concentration.

• 한국해양학회지
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• v.29 no.4
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• pp.338-356
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• 1994

Sediment samples from the continental shelf of the South Sea of Korea are analysed to determine the concentration of Al, Fe, Mn, cu, Ni, Zn, Co, Cr and Pb. among these samples, fine-grained sediments were also analysed by a sequential extraction technique to know geochemical forms of the metals in this environments. The total concentration of Al, Fe, Cr, Ni, Cu and Zn in bulk sediments decreased gradually with the increase of distance from the coastal zone. This distribution patterns are well coincide with grain size distribution. However, the patterns of Mn, co and Pb do not follow such and overall distribution. The concentration of Pb, particularly, did not show any features in areal distribution, which may be result from different pathways to the sediments, compared to the other metals. the speculation data show that a considerable amount of Cd, Mn and Co are bounded in the carbonate fraction, accounting for 42.8%, 40.3% and 30.6%, respectively. Cu, Zn, Mn and Fe are largely associated to oxide fraction with proportions of 34.4%, 23.1%, 15.5% and 13.7%, respectively. However, the metals in residual fraction account for more than 50% of the total metal concentration, except for Mn. These observations emphasize that residual fraction in the dominant component controlling the elemental concentration.quartz and glauconite grains.Accordingly,these sediments are interpreted as an extension part of transgressive sand deposit that are widely distributed on the continental shalf floor of southern Yellow Sea.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.360-364
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• 1998

The sun-dried, refined, and processed salt (roasted and bamboo salt) manufactured in Chonbuk province were analyzed their chemical compositions and minerals including heavy metals for safety evaluation. Average content of each eomponent as the lowest and the highest were as follows-pH; 6.80 (refined) to 10.35 (bamboo), water content; 0.13% (bamboo) to 10.7% (sun-dried), sodium chloride; 96.6% (roasted) to 84.3% (sun-dried), 804; 0.59% (bamboo) to 3.0% (sun-dried), water insoluble matters; 0.001% (refined) to 1.98% (bamboo), acid inoluble matters; <0.001% (refined) to 0.21% (bamboo), calcium; 0.038% (refined) to 0.213% (sun-dried), magnesium; 0.111% (refmed) to 1.078% (sun-dried), lead; 0.45 ppm (refmed) to 1.15 ppm (bamboo). Cadminium, arsenic and mercury were not detected in all salt. As the analytical results, all salts were differtent in their chemical compositions and safe in view of heavy metals.

• The Korean Journal of Ecology
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• v.23 no.1
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• pp.9-15
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• 2000

The effects of clearcutting on soil chemical ingredients and stream water quality have been investigated at a natural deciduous forest catchment within the Seoul National University Research Forest in Mt. Paekun, Chunnam province during the periods of 1993 to 1998. Soil chemical ingredients and stream water qualities were monitored at a 13 ha clearcutting site and a non-treatment site nearby. During the first and second years after harvesting, the levels of total-N, and exchangeable ions (K/sup ＋/, Na/sup ＋/, Ca/sup 2＋/, Mg/sup 2＋/) decreased compared to the values of before harvesting. During the fifth years after harvesting, these levels were significantly higher than those during the first and second years after harvesting. But the chemical characteristics of soil were not changed at all. pH of water in the harvesting area was 6.5 in stream water. Among the nutrients, Cd, Pb, Cu, and phosphate were not found, and the level of BOD reached at the level of the domestic use suitable for drinking. Turbidity, odor, taste, NH/sub 4//sup ＋/ -N, NO/sub 3//sup -/-N, standard plate count, and coliform were also low enough to be used as the domestic use for drinking by the near villagers. During the first and second years after harvesting, BOD increased to about 1 ppm. For that reason, the harvesting planning should be built in the harvesting area in consideration of the control of water quality in the stream.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.829-836
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• 1995

This study was performed to evaluate the relationship between dietary, blood and urinary levels of lead and blood pressure and serum lipids in 30 healthy adult living in rural area of Korea. Analysis for the nutritional status of subjects were performed by 3-day dietary intake record, duplicated diet collection, 24-hour urine collection, and venous blood sampling before anthropometry. The mean daily intakes of lead estimated for 3 days was $120.1{\pm}22.0\mu\textrm{g}$. The blood levels and 24-hour urinary excretion of lead were $10.8{\pm}3.6\mu\textrm{g}/dl\;and\;36.5{\pm}9.5\mu\textrm{g}$, respectively. The systolic and diastolic blood pressure were $113.0{\pm}16.9mmHg\;and\;76.7{\pm}12.1\;mmHg$. The serum levels of total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol and ${\beta}-lipoprotein$ were $158.8{\pm}32.9mg/dl,\;104.6{\pm}48.8mg/dl,\;45.7{\pm}9.9mg/dl,\;92.2{\pm}28.5mg/dl\;and\;426.4{\pm}141.5mg/dl$, respectively. There was no significance in the relation between lead and blood pressure. In the relation between lead and serum lipids, it showed negative correlation with lead intake and HDL-choleterol at the level of significance of p<0.01. But there was no significance in the relation between lead and serum levels of otehr lipids.

• Korean Journal of Microbiology
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• v.50 no.1
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• pp.33-39
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• 2014

One hundred forty four bacterial colonies which were able to degrade crude oil were isolated from soil samples that were contaminated with oil in Daejeon area. Among them, one bacterial strain was selected for this study based on its emulsification activity, growth rate and surface tension activity, and this selected bacterial strain was identified as Pseudomonas sp. HN37 through physiological- biochemical tests and analysis of its 16S rRNA sequence. Pseudomonas sp. HN37 utilize the several aliphatic hydrocarbons, 3,5-dinitrosalicylic acid and 2,4-dichlorophooxyacetic acid as a sole carbon source. And this bacterial strain showed a high resistance to antibiotics such as ampicillin and chloramphenicol, as well as heavy metals such as Ba, Cr, Li and Mn. Also, it was found that the optimal pH and temperature for the cell growth, surface tension, and emulsification activity of Pseudomonas sp. HN37 were pH 6.0-9.0 and $30^{\circ}C$, respectively. The emulsification and surface tension activity was reached the maximum to 1% (V/V) crude oil and 1% (W/V) NaCl concentration. The surface tension of the culture broth was decreased from 62 to 27 dyne/cm after fifteen hours of inoculation in LB media.