• Economic and Environmental Geology
• /
• v.22 no.1
• /
• pp.35-63
• /
• 1989

Geochemical characteristics of the Guryongsan (Ogcheon) uraniferous black slate show that this is an analogue to the conventional Chattanooga and Alum shales in occurrences. Whereas, its highest enrichment ratio in metals including uranium, among others, is explained by the cyclic sedimentation of the black muds and quartz-rich silts, and the uniform depositional condition with some what higher pH condition compared to the conditions of the known occurrences. The cyclic sedimentation, caused by the periodic open and close of the silled basin, has brought about the flush-out) of the uranium depleted water and the recharge with the new metal-rich sea water, which consequently contributed to the high concentration of metals in mud. The metal-rich marine black muds, which mostly occur in the early to middle Palaeozoic times, is attributed by the geologic conditions which related to the atmospheric oxygen contents, and these are scarcely met in the late Precambrian and/or with the onset of Palaeozoic era in the geologic evolution of the earth.

• Journal of agriculture & life science
• /
• v.46 no.3
• /
• pp.97-108
• /
• 2012

Physical, chemical and biological hazards of strawberry farms at the cultivation stage were analyzed to establish the GAP(Good Agricultural Practice) system. Samples were collected from the plants, cultivation environments(water, soil and air), and personal hygiene (hand, glove, and clothes) of three strawberry farms(A, B, and C) and were tested to analyze physical, chemical (heavy metals and pesticide residues), and biological(sanitary indications and foodborne pathogens) hazards. Physical hazards such as insects and pieces of metal and glass were found in the strawberry farms and can be potential bow for strawberry products. Heavy metal and pesticide residue as chemical hazards were detected at levels lower than the regulation limit. In case of biological hazards, total bacteria and coliform were detected at the levels of 1.6~7.3 and 1.3~5.6 log CFU/g, leaf, mL, hand or $100cm^2$. However, Escherichia coli was not detected in all samples. Bacillus cereus and Staphylococuus aureus were detected at levels of ${\leq}$ 1.1~6.1 log CFU and 4.7~5.4 log CFU/g, mL, hand or $100cm^2$, whereas Listeria monocytogenes, E. coli O157 and Salmonella spp. were not detected in all samples. This study demonstrates that various harzards were in strawberry farms at the growing stage. Therefore proper management such as GAP is needed to prevent the occurrence of food poisoning associated with the hazards revealed in this study.

• Korean Journal of Soil Science and Fertilizer
• /
• v.39 no.6
• /
• pp.339-344
• /
• 2006

A lot of organic wastes have been produced from diverse industries, they must be tested by the regulation of fertilizer control act if reuse the organic wastes for agricultural utilization. The regulation has had only two criteria; the content of organic matter and 8 heavy metals. This study was conducted to evaluation trace element (boron, cobalt, molybdenum, and selenium) and distribution of organic compounds with different classification for complement the regulation in 16 organic waste materials(62 samples) collected from different regions and industries. Contents of boron(leather industry sludge, $154.2mg\;kg^{-1}$; food company sludge, $57.1mg\;kg^{-1}$), cobalt(industrial area sewage sludge, $95.2mg\;kg^{-1}$; metropolitan sewage sludge, $22.9mg\;kg^{-1}$), molybdenum(metropolitan sewage sludge, $40.1mg\;kg^{-1}$; food company sludge, $16.8mg\;kg^{-1}$), selenium (fiber industry sludge, $28.1mg\;kg^{-1}$; leather industry sludge, $16.9mg\;kg^{-1}$; food company sludge, $15.9mg\;kg^{-1}$) were highest compare to the other organic wastes. Total PAHs contents were the highest in paper-mill manufacture($3,462ug\;kg^{-1}$), and among the 16 PAHs, naphthalene, phenanthrene, pyrene, fluoroanthene, Anthracene and acenaphthene were detected more clearly than others in all kinds of organic resources.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.2
• /
• pp.108-117
• /
• 2005

Pharmaceutical byproduct sludge and cosmetic industry wastewater sludge can be used as a raw material of compost. Effects of three types of pharmaceutical byproduct sludge and one type of cosmetic industry wastewater sludge on soil properties and red pepper growth were investigated in a field based concrete pot ($2{\times}2m$). These sludges and pig manure ($5Mg\;ha^{-1}$, dry basis) were incorporated into the upper of loam soil 30 days prior to transplanting red pepper. Changes in soil properties and contents of heavy metals and toxic organic compounds in soil and plant were measured. And also plant growth measurement and bioassay of soil phytotoxicity were included. Contents of heavy metals were increased in the soils treated with the sludges. Plant growth in the sludge treatments were mostly inferior to that of NPK treatment, especially in early stage. Content of N in plant was lower in all sludge treatments at early and middle growth stages, and it was especially caused by characteristics and concentration of nitrogen and organic matter of sludges. Total yield of red pepper was highest in the NPK treatment and followed by pharmaceutical sludge 3, pig manure, pharmaceutical sludge 1, and pharmaceutical sludge 2, and the yield of cosmetic sludge treatment was considerably lower than others. HEM and PAHs contents in soil of cosmetic sludge treatment were $4.80mg\;kg^{-1}$ and $2,263.2{\mu}g\;kg^{-1}$, respectively. Root elongation of lettuce exposed to the water extract of soil treated with cosmetic sludge was about 20% of that found in the test with soil extract of non fertilization treatment. At present, raw materials of compost were authorized according to the contents of organic matter, heavy metals and product processing. Toxic organic compounds analysis and bioassay would be helpful for authorization and assessment of suitability of raw materials of compost.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.6
• /
• pp.923-929
• /
• 2010

This study was conducted to investigate the relations between soil chemical properties and Korean raspberry (Rubus coreanus Miq.) growth. Soils were collected from 54 sampling sites in 1 to 6 years old Korean raspberry cultivation fields (RCFs) at Gochang-gun, Jeollabuk-Do, Korea. In RCF with two to six years old plants, soil pH and exchangeable $Ca^{2+}$ and $Mg^{2+}$ contents were higher at the leaf-emergence time, but EC, available phosphorus content, CEC, and total nitrogen content were higher at the harvesting time; especially at the harvesting time, the content of available phosphorus in the RCF with 3~6 years old plants were at least three times higher than in the RCF with 2 years old plants. Water-soluble anions ($Cl^-$, ${NO_3}^-$, ${PO_4}^{2-}$, and ${SO_4}^{2-}$) in the RCF were also measured. The contents of ${NO_3}^-$ and ${SO_4}^{2-}$ were always higher in the RCF with older plants than in the RCF with younger plants, which were not affected by sampling time and sampling locations (rhizosphere and non-rhizosphere sites). However, soils collected from non-rhizosphere at the leaf-emergence time contained higher ${PO_4}^{2-}$ content, but $Cl^-$ content was higher in the soils collected from rhizosphere at the harvesting time. In general, soils in the RCFs contained excess amounts of inorganic nutrients such as available phosphorus and exchangeable $K^+$. Thus, optimal levels of soil properties for Korean raspberry cultivation should be reconsidered.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.26 no.4
• /
• pp.21-29
• /
• 2018

The contents of total nitrogen(T-N), phosphate($T-P_2O_5$), and potash($T-K_2O$) are important factors to determine the application rate of the livestock compost to prevent nutrients accumulation and maintain their appropriate levels in arable lands. The concentrations of nutrient, organic matter, salt, water content, heavy metal in livestock compost in circulation were investigated with 659 samples from 2016 to 2017. In order to investigate the fluctuation nutrient contents of livestock composts with the same product name, 19 samples were collected and analyzed T-N, and $T-P_2O_5$, and $T-K_2O$ concentration during two years. The mean levels of T-N, $T-P_2O_5$, and $T-K_2O$ in livestock composts of from 2016 to 2017 were 1.73%, 1.88%, and 1.66%, respectively. The average contents of organic matter, water, and salt were 38.9%, 40.9%, and 1.2%, respectively. There were found that the maximum concentrations of Cr, Ni, Cu, and Zn in some livestock composts were exceeded the criteria of the official standard of commercial fertilizer. The maximum variation coefficient of T-N, $T-P_2O_5$ and $T-K_2O$ content of livestock composts was found to be 24%, 27%, and 50% on average, respectively. In order to manage the nutrients in agricultural soils, it will be reasonable that the error range of T-N and $T-P_2O_5$ content in livestock composts should be recommended to be 27% in mean as variation coefficient in case of displaying the nutrient element in liverstock compost.

• Clean Technology
• /
• v.25 no.3
• /
• pp.256-262
• /
• 2019

Hydroxylammonium nitrate (HAN)-based liquid propellants are attracting attention as environmentally friendly propellants because they are not carcinogens and the combustion gases have little toxicity. The catalyst used to decompose the HAN-based liquid propellant in a thruster must have both low temperature activity and high heat resistance. The objective of this study is to prepare an Ru/alumina/metal foam catalyst by supporting alumina slurry on the surface of NiCrAl metal foam using a washing coating method and then to support a ruthenium precursor thereon. The decomposition activity of a HAN aqueous solution of the Ru/alumina/metal foam catalyst was evaluated. The effect of the number of repetitive coatings of alumina slurry on the physical properties of the alumina/metal foam was analyzed. As the number of alumina wash coatings increased, mesopores with a diameter of about 7 nm were well-developed, thereby increasing the surface area and pore volume. It was optimal to repeat the wash coating alumina on the metal foam 12 times to maximize the surface area and pore volume of the alumina/metal foam. Mesopores were also well developed on the surface of the Ru/alumina/metal foam catalyst. It was found that the metal form itself without the active metal and alumina can promote the decomposition reaction of the HAN aqueous solution. In the case of the Ru/alumina/metal foam-550 catalyst, the decomposition onset temperature was significantly lowered compared with that of the thermal decomposition reaction, and ${\Delta}P$ could be greatly increased in the decomposition of the HAN aqueous solution. However, when the catalyst was calcined at $1,200^{\circ}C$, the catalytic activity was lowered inevitably because the surface area and pore volume of the catalyst were drastically reduced and Ru was sintered. Further research is needed to improve the heat resistance of Ru/alumina/metal foam catalysts.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.3
• /
• pp.779-788
• /
• 2019

An experiment was conducted with 240 broiler chickens (ROSS 308) to evaluate the influence of supplementation of a probiotic feed mixture (PFM) including Bacillus subtillus, Streptomyces galilaeus, and Sphingobacteriaceae on growth performance and quality of chicken meats. Broiler chickens were randomly allocated to one of four treatment groups: 1) CON (no PFM as control), 2) CP3 (0.3% commercial probiotics), 3) PFM3 (0.3% PFM), and 4) PFM5 (0.5% PFM 0.5). They were then reared for 35 days. Body weight was significantly increased in CP3, PFM3, and PFM5 compared to that in CON (p<0.05). In addition, PFM3 and PFM5 had higher body weights then CP3 (p<0.05). Weights of F-sac, thymus, and spleen and IgG levels were significantly higher in CP3, PFM3, and PFM5 than those in CON (p<0.05). In addition, they were higher in PFM3 and PFM5 than those in CP3 (p<0.05). Broiler chickens fed diet with PFM3, PFM5, and CP3 also had higher numbers of Lactobacillus in cecum than broiler chickens fed CON diet (p<0.05). However, their numbers of E. coli, Salmonella, coliforms, and total aerobic bacteria were significantly reduced (p<0.05). Water holding capacity of breast meat was significantly improved in PFM3 and PFM5 compared to that in CON and CP3 (p<0.05). These results suggest that dietary 0.3% probiotic feed mixture including Bacillus subtillus, Streptomyces galilaeus, and Sphingobacteriaceae may improve growth performance and meat quality of broiler chickens.

• Journal of Life Science
• /
• v.29 no.2
• /
• pp.265-271
• /
• 2019

In general, specific gravity (SG) and urinary creatinine (CR) have been used to adjust urinary cadmium (Cd) concentrations. However, the validity of correction methods has been controversial. We compared the two adjustments to evaluate associations between urinary Cd and various renal damage markers and to evaluate the relationship between urinary Cd concentration and renal disease markers, such as estimated glomerular filtration rate (eGFR), in a relatively large general population sample. Among the 1,086 volunteers who were enrolled in this study, 862 healthy volunteers who did not have kidney disease were included in the final analysis. Urinary Cd, malondialdehyde (MDA), and N-acetyl-${\beta}$-D-glucosaminidase (NAG) concentrations were measured, the creatinine-based eGFR was calculated, and the relationships between these markers were subsequently analyzed. This study showed the use of urinary Cd concentration adjusted with SG rather than with urinary creatinine may be appropriate in studies evaluating renal function based on Cd exposure. Urinary Cd concentration adjusted with SG had a positive correlation with urinary MDA levels and a negative correlation with eGFR. This relationship was relatively stronger in women than in men. This study showed that urinary Cd level was associated with decreased eGFR in the general population, and oxidative stress was likely to act as an intermediator in this process. These results suggest that eGFR can be a very good indicator of kidney damage caused by Cd exposure in the general population.

• Journal of Korean Society of Forest Science
• /
• v.109 no.4
• /
• pp.371-381
• /
• 2020

The Ministry of Environment (ME) is planning to adopt in 2020 the IUCN regional Red List for "Guidelines for listing and delisting rare & endangered species and management of endangered Species System". The ME designated 377 species of vascular plants on the regional Red List. In a previous study it had been suggested that 103 species from this list are candidates for the regional Red List. With respect to a possible Red List, we assessed 59 species (after excluding 34 additional NA species and ten endemic species). These assessments indicated that 16 species are at the "threatened" level. Of those, one species is Critically Endangered, ten are Endangered, and five are Vulnerable. A further four species are classified as Near Threatened, 30 as Of Least Concern, and nine as Data Deficient. We found that most of the assessments proposed by the Ministry of Environment were not supported by scientific data, including quantitative geographic data (over 70%) in Criteria B. In order to determine the endangered species belonging to the orchid family, it is necessary to obtain records of illegal activities or data on overcollection. The current problem with the Ministry of Environment Red List has been the lack of management of scientific data on species showing a trend in decreasing population in the mid- to long-term; thus, there is a lack of critical resources for policy-makers. The ME legally designated categories and assessment, and the lack of expertise in failing to comply with the legal law by itself. The key to presenting an accurate overview of the state of Korean flora is to fill the information gaps with respect to significant geographical and taxonomical biases in the quality and quantity of data. By regularly updating the qualified data, we will be able to track the changes in the conservation status of the flora and inform the necessary conservation policies.