• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.169-175
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• 2003

For safe and easy disposal of prochloraz wastewaters after used as rice seed disinfectant in Korean farms, this experiment was carried out. By addition of several agricultural materials commonly utilizing in farmers, removal effect of prochloraz from waste solution was also investigated. When rice seeds after soaking in diluted prochloraz solution were rinsed with water several times, prochloraz was removed $9.2\sim10.6%$ at the first rinse and less than 3 % at the fourth rinse. A half life of prochloraz was $4\sim5$ days in aqueous system. Hydrolysis of prochloraz was more rapidly in alkali solution than neutral and acidic one at $25^{\circ}C$ and $35^{\circ}C$. By the irradiation under $5530J/cm^2$ using xenone lamp, prochloraz was photo-degraded to 87.7% in aqueous system. The removal efficiency of prochloraz by addition of several agricultural materials were as follows: 93.6% by lime, 90.7% by composed pig manure, 89.4% by activated charcoal, 78.0% by straw ash, 70.3% by sandy loam soil, 47.0% by zeolite and 24.1 % by rice straw. When prochloraz solution was sprayed on the field soil, it was dissipated upto 90% within 35 days.

• Resources Recycling
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• v.14 no.6 s.68
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• pp.3-9
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• 2005

In this study, the separation and recovery of cerium hydroxide was investigated from the wasted cerium polishing powders. Waste cerium polishing powder contains $64.5\;wt\%$ of rare earth oxide and the content of cerium oxide is $36.5\;wt\%$. Since cerium oxide, $56.3\%$ of rare earths, is the most stable state in rare earth, the dissolution of cerium oxide in acid solution is not easy. Therefore the process of rare earth oxide by sulfation and water leaching was examined in order to increase the recovery of rare earth. Rare earth elements were recovered in the form of $\Re{\cdot}Na(SO_{4})_{2}$ by the addition of sodium sulfate to leached solution. The slurry of rare earth hydroxide was prepared by the addition of $\Re{\cdot}Na(SO_{4})_{2}$ to sodium hydroxide solution. After the oxidation of cerous hydroxide($CE(OH)_{3}$) to ceric hydroxide($CE(OH)_{3}$) by aeration, ceric hydroxide was separated from other rare earth hydroxides by controlling the acidity of solution.

• Resources Recycling
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• v.22 no.3
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• pp.91-99
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• 2013

Steel industry which has been accomplishes the base of our country economy, automobile and electronic industry are taking charge of the role, whose electroplating is important. Large amount of wastewater and various metal salts, including hazardous materials was generated from the electroplating pre-treatment, plating, washing and post-plating. Currently, the general wastewater follows in the environmental law and neutralization after controlling, sludge where the various metal is mixed reclaims below multiple regulative and trust it is controlling. The sludge which includes the gas price metal reclaims in the field and trust it controls. a reclamation price of land it is insufficient but and the control expense holds plentifully and it loses the gas price metal which is valuable. Consequently, The research regarding to recover a gas price metal actively from this waste water, it is advanced. A new method to recover valuable metals from electroplating wastewater synthesis of metal sulfides using topical methods utilizing iron oxidizing bacteria, reagent of sulfides and solvent extraction using an organic solvent, such as the development of the law to recover these metals and metal sulfides of wastewater using selective recovery have been studied. By using these wastewater treatment method under frequency above 95%, it has been obtained the valuable metal from the wastewater, where the metal ion of Fe, Cu, Zn and Ni complexes was mixed. As we discuss the wastewater, which has been discharged from electroplating process, it is important and will be applied to the resources of metal in the urban mine.

• International Journal of Highway Engineering
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• v.12 no.3
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• pp.87-92
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• 2010

As the Concept "how environmental friendly" becomes more and more important in road construction. However, so far there is no estimation method. Environmental friendly concept can be incorporated at the plan level in order to influence decision making, and support policies that affect environment. The overall goal of this study was to develop environmental friendly concept measures for the national highway and to develop a methodology to implement a more environmental friendly concept. The research identified 8 performance measures through a project analysis that could address environmental impact assessment system's ten strategic goals - Topography, Wildlife, hydrology, landuse, air quality, water quality, soil, waste, noise, landscape. The qualitatively and quantitatively evaluation approach was selected as the decision support framework and performance measure were investigated using the AHP(Analytic Hierarchy Process) and pilot corridor for a 10 section and calculate the index values. The methodology was applied to a pilot corridor comprised of a 120km section of national highway in korea. The methodology made it possible to identify the specific performance measures that need improvement to enhance the overall environmental friendly concept. It is fairly intuitive, based on readily available data, and is easy to apply. It provides a powerful tool for government to assess the relative environmental friendly conceptof their transportation corridors now and in the future. It allows for comparisons within a corridor and with other corridors and identifies the improvements needed to enhance the environmental friendly concept.

• Journal of Oriental Physiology
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• v.14 no.2 s.20
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• pp.189-198
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• 1999

Aminoglycosides, including gentamicin, have been used as antibiotics for the various infections by gram-negative bacteria. However, there are some restrictions for using these drugs. Gentamicin, a typical aminoglycoside, has the side effect of nephrotoxicity, including polyuria, glycosuria, proteinuria, glomerulonephritis, and uremia. The aims of this study were to examine the prevention or reduction effects of Jinmootang on the gentamicin-induced nephrotoxicity and to investigate the possible mechanisms on the effect of Jinmootang. The subcutaneous injections of 60mg of gentamicin per kg of boby weight to Sprague-Dawley rats for 8 days induced typical symptoms of nephrotoxicity by aminoglycosides. 0.6ml of water extract Jinmootang (100ml/chup) was orally treated in the experimental animal. 24-hour urine was collected with the metabolic cage and plasma was sampled from the abdominal aorta. The plasma concentration of sodium was significantly decreased by the treatment of gentamicin but it was not-significantly changed by the treatment of Jinmootang to the animal. The concentration of potassium was greatly decreased in the gentamicin-treated animals. However. it was returned to the normal level in the Jinmootang-treated animals. The concentrations of creatinine and urea were increased by gentamicin treatment. But, Jinmootang reduced these concentrations. Nevertheless, the osmolalities of plasma in both group were not different from each other. Even though the plasma concentration of aldosterone was not significantly changed, the mean value was increased by the gentamicin intoxication. The concentration of aldosterone was decreased by the treatment of Jinmootang. The reduction of aldosterone level in plasma could be a factor to improve the hypokalemia. The fractional excretion of potassium was much higher than normal by the treatment of gentamicin and it was decreased by 50% in the Jinmootang-treated rats. Therefore, the reabsorption of potassium was significantly increased by the treatment of Jinmootang, even though the filtered load of potassium in the experimental group was much highter than control. Even though the concentration of plasma aldosterone was decreased by the treatment of Jinmootang, the fractional excretion of sodium was not increased, slightly lower. These data suggested that Na reabsorption was increased in the proximal tubule by Jinmootang. The filtered load of glucose in the Jinmootang-treated group was greater than in control. Nevertheless, the fractional excretion of glucose in the experimental group was not different from that in control. These results indicate that glucose reabsorption was increase in the proximal tubule by Jinmootang treatment. The results of this study suggest that Jinmootang could improve the some nephrotoxic symptoms induced by gentramicin treatment. Hypokalemia, the reduced glomerular filtration rate, and dysfunctions of renal proximal tubule and distal nephron were significantly recovered to normal level. The increase of glomerular filtration rate by Jinmootang might contribute to eliminate the waste product, including creatinine and urea, and/or gentamicin through the kidney.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.558-566
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• 2017

In this study, we developed an electron-emission OH radical generator for waste water treatment. The stability of the circuitry was ensured by implementing stable pulse waves with a MOSFET and reducing the momentary current rise. The OH radical generator uses a high-voltage and low-current discharger. The performance of the device was evaluated experimentally, which showed that it is possible to produce a stable and uniform pulse waveform for the drain current of the power MOSFET, which is connected to the input side of an AC multiplying converter through negative feedback circuitry with CR-snubber architecture. It was also possible to reduce the excitation current of the converter and improve the stability of the oscillation circuit. In addition, the generator can generate hydroxyl radicals stably. The bactericidal activities were also evaluated, and the germicidal power for E. coli, S. aureus, and S. flexneriwas improved by 99.9% or more after 60 minutes.

• Resources Recycling
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• v.29 no.4
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• pp.15-30
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• 2020

Recently, it is increasing a amount of installed solar-cell rapidly, and end-of-life photovoltaic(ELP) modules are generated in according to the reduction of cell efficiency largely. Recycling of ELP modules are begun at an advanced nation already, but there are bring about environmental contamination and resource recovery problems owing to not treated ELP modules because of economic cost completely. First of all, there were researched basic study for treatment conditions of used solar cell inspection, dismantling of aluminum frame, crushing / grinding & separation of tempered glass, removal of back sheet & EVA film, leaching & precipitation recovery of valuable metals and treatment of waste water. Therefore, we establish optimum conditions through carried out of designed apparatus, installation of equipment, test operation & trouble shooting in scale of 1ton/day pilot plant test. Following to economic review, it does have the economic efficiency until to the case of tempered glass recovery, but does not have the economic value in case of total processes until to recover the valuable metals. However, there are guaranteed economic value if we are gained a large amount of the expenses through EPR supported system. It was confirmed the commercialized possibility of ELP modules recycling if there were established on the collecting ELP modules, reusing criteria, economical technology, enactment of directives and enforcement of EPR supported system efficiently.

• The Journal of Engineering Geology
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• v.29 no.3
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• pp.265-277
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• 2019

Changes in the amount, intensity, frequency, and type of precipitation, in conjunction with global warming and climate change, critically impact groundwater recharge and associated groundwater level fluctuations. Monthly gravity levels by the Gravity Recovery and Climate Experiment (GRACE) are acquired to monitor total water storage changes at regional and global scales. However, there are inherent difficulties in quantitatively relating the GRACE observations to groundwater level data due to the difficulties in spatially representing groundwater levels. Here three local interpolation methods (kriging, inverse distance weighted, and natural neighbor) were implemented to estimate the areal distribution of groundwater recharge changes in South Korea during the 2002-2016 period. The interpolated monthly groundwater recharge changes are compared with the GRACE-derived groundwater storage changes. There is a weak decrease in the groundwater recharge changes over time in both the GRACE observations and groundwater measurements, with the rate of groundwater recharge change exhibiting mean and median values of -0.01 and -0.02 cm/month, respectively.

• Journal of Soil and Groundwater Environment
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• v.21 no.1
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• pp.28-39
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• 2016

Struvite (MgNH₄PO₄ ⋅ 6H₂O) and hydroxyapatite (HAP, Ca₁₀(PO₄)₆(OH)₂) precipitation in urine-separating toilets (NoMix toilets) causes severe maintenance problems and also reduce the phosphate and calcium content. Application of urine separating technique and extraction of by-products from human urine is a cost effective technique in waste water treatment. In this study, we extract urine calcite from human urine by batch scale method, using urease producing microbes to trigger the precipitation and calcite formation process. Extracted urine calcite (calcining at 800℃) is a potential adsorbent for removal of heavy metal(loid)s like (Cd²⁺, Cu²⁺, Ni²⁺, Pb²⁺, Zn²⁺ and As³⁺) along with additional leaching analysis of total nitrogen (T-N), phosphate (T-P) and chemical oxygen demand (COD). The transformations of calcite during synthesis were confirm by characterization using XRD, SEM-EDAX and FT-IR techniques. In additional, the phosphate leaching potential and adsorbate (nitrate) efficiency in aqueous solution was investigated using the calcinedurine calcite. The results indicate that the calcite was effectively remove heavy metal(loid)s lead up to 96.8%. In addition, the adsorption capacity (q_e) of calcite was calculated and it was found to be 203.64 Pb, 110.96 Cd, 96.02 Zn, 104.2 As, 149.54 Cu and 162.68 Ni mg/g, respectively. Hence, we suggest that the calcite obtain from the human urine will be a suitable absorbent for heavy metal(loid)s removal from aqueous solution.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.469-476
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• 2015

Button mushroom compost (BMC) was prepared by fermenting the mixture of waste button mushroom bed collected from Boryeong area in South Korea (4): sawdust (8) : pig and fowl manure (1) for 40 days at $30^{\circ}C$. The BMC compromised diverse microorganisms including aerobic bacteria $8.1{\times}10^6cfu\;g^{-1}$, Gram negative bacteria $1.7{\times}10^7cfu\;g^{-1}$, genus Bacillus $6.4{\times}10^6cfu\;g^{-1}$, genus Pseudomonas $1.5{\times}10^4cfu\;g^{-1}$, actinomycetes $1.0{\times}10^4cfu\;g^{-1}$, and fungi $3.5{\times}10^3cfu\;g^{-1}$. BMC was used as a microbial inoculant for estimating the mobilization of heavy metals in soil or plant. When metal solubilization potential of BMC was assessed in a batch experiment, the inoculation of BMC was shown to increase the concentrations of water soluble Co, Pb, Cd, and Zn by 29, 26, 27, and 43% respectively, than those of non-inoculated soils. BMC-assisted growth promotion and metal uptake in sunflower (Helianthus annuus) was also evaluated in a pot experiment. In comparison with non-inoculated seedlings, the inoculation led to increase the growth of H. annuus by 17, 15, 18, and 21% respectively in Co, Pb, Cd, and Zn contaminated soils. Moreover, enhanced accumulation of Co, Pb, Cd, and Zn in the shoot and root systems was observed in inoculated plants, where metal translocation from root to the above-ground tissues was also found to be enhanced by the BMC. The apparent results suggested that the BMC could effectively be employed in enhancing phytoextraction from the soils contaminated with heavy metals such as Co, Pb, Cd, and Zn.