• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.989-994
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• 2005

The treatment efficiency and the degradation characteristics of humic acid were investigated in three processes-GAC adsorption, Ozone alone and Ozone/GAC hybrid process, in which $UV_{254}$, DOC, molecular size distribution and surface change of GAC were evaluated. DOC removal rate in Ozone/GAC hybrid profess(ca. 80%) was higher than the arithmetic sum of Ozone alone(38%) and GAC adsorption(19%). This result approves that the combined Ozone/GAC hybrid process brings synergistic effects on DOC removal from the HA containing water. $UV_{254}$ decrease rate was also at the highest in Ozone/GAC hybrid process from the three processes. It may be interpreted that the granular activated carbon in Ozone/GAC hybrid process acts as not only an adsorbent but also a catalyst for ozonation, and futhermore offers an additional reaction site between adsorbed organic matter and ozone. In the study of molecular sire distribution, there was no significant change of molecular size distribution in the GAC adsorption process during the reaction time of 120 min. In Ozone alone process, the fraction of molecular size over 30 kDa was decreased a little at the beginning and left constant after 10 min. But in Ozone/GAC hybrid process, the molecules size over 30 kDa of HA was significantly decreased from 36.3% to 3.9%. And also the fraction of smaller molecular size below 0.5 kDa was increased from 4.8%(untreated HA) to 12.3%(in Ozone alone) and 40.1%(in Ozone/GAC) respectively at the reaction time of 120 min.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.2
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• pp.205-213
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• 2007

We have studied NOM(natural organic matters) adsorption and biodegradation on 3 kinds of activated carbon and a anthracite. Coal based activated carbon showed the highest DOC(dissolved organic carbon) adsorption capability and roconut(samchully), wood (pica) in the order among the 3 kinds of activated carbon(F400). The biomass amount and activity also showed on coal, wood and coconut based activated carbon in the order. Over 15 minutes EBCT(empty bed contact time) needed to achieve 10 to 17% average removal efficiency and $18\sim24%$ maximum removal efficiency of NOM biodegradation in biofilter using anthracite. Hydrophobic and below 10,000 dalton NOM was much easier to adsorb into the activated carbon than hydrophilic NOM, THMFP(trihalomethane formation potential) and BDOC (biodegradable dissolved organic carbon)$_{slow}$ were much easier than HAA5FP(haloacetic acid 5 formation potential) and $BDOC_{rapid}$ to adsorb into the activated carbon. Hydrophilic and below 1,000 dalton NOM was much easily biodegraded and HAA5FP and $BDOC_{rapid}$ was easier than THMFT and $BDOC_{slow}$ to biodegrade in the biofilter.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.419-424
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• 2007

According to increase of consumer's desire for clean tap water, advanced treatment processes include with membrane, ozone, and granular activated carbon(GAC) were introduced. In order to evaluate the effect of advanced treatment processes for residual chlorine decay and trihalomethane(THM) formation in water distribution system, dissolved organic matter(DOC) removal of each advanced treatment process was investigated. The residual chlorine decay and THM formation using bottle tests were also evaluated. $UV_{254}$ removal in all advanced treatment was better than DOC removal. Especially, DOC by ozone treated was removed as 4% in contrast with sand filtered water, but $UV_{254}$ was removed about 17%. This result might be due to convert from hydrophobic DOC to hydrophilic DOC by ozonation. Ozone/GAC process was most effective process for DOC removal. The residual chlorine decay constants in treated water by sand filtration, ozonation, GAC adsorption, and ozone/GAC processes were 0.0230, 0.0307, 0.0117 and 0.0098 $hr^{-1}$, respectively. The sand filtered water was produced 81.8 ${\mu}g/L$ of THM after 190 hours of reaction time, as the treated water by ozone, GAC, and Ozone/GAC was less produced 6.0, 26.2, 30.3% in contrast with sand filtered water, respectively. Consequently, the durability of residual chlorine and reduction of THM formation were improved by advanced treatment processes.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.2
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• pp.63-70
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• 2013

Experiments in a pilot-scale hybrid multi-stage unit system (HMUS) combination of ATAD and EGSB followed by SBR process for pig slurry treatment were conducted to demonstrate the feasibility of using autothermal thermophilic aerobic digestion (ATAD) and expended granular sludge bed (EGSB) followed by sequencing batch reactor (SBR) system. Contaminants in pig slurry with high organic matter, nitrogen (N) and phosphorus (P) content were completely removed in the combined process. The highest removal rate for CODcr among contaminants in the feed pig slurry was attained by about 43.3% in ATAD unit process. Also TS removal rate of 96.5% was attained and the highest in the next coagulation unit process. The highest removal rate of CODcr under operating parameter conditions of OLR(organic loading rate), 3-6Kg $COD/m^3{\cdot}day$ and line velocity, 1.5-4m/h was earned at 3days of HRT. The disinfection of pathogens was effective at 50,000mg/L of TS in ATAD unit process. Biogas production per organic removal was $2.3{\sim}8.5m^3/kgTS{\cdot}d$ (average $5.2m^3/kgTS{\cdot}d$) in EGSB unit process. The average removal rates of CODcr 71.7%, TS 64.1%, TN 45.9%, and TP 50.4% were earned in the intermittent aeration SBR unit process.

• Journal of the Mineralogical Society of Korea
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• v.2 no.2
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• pp.73-80
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• 1989

The sedimentary siderite rock or siderostone has been firstly found from the upper part of the Cambrian Myobong Slate in the Sangdong Tungsten Mine area. It occurs as layers between slate and calc-silicate rock (originally siliceous ankerite rock and ferroan dolostone) or within calc-silicate rock. Some parts of the siderostone bed, however, are considerably skarnized to iron-rich skarns, leaving only small-scaled relics. Siderostone consists mainly of siderite and quartz with minor amount of bertioerine and fluorite or apatite and is commonly microcrystalling granular in texture. Stratification is well developed in some siderstone. The siderostone and its skarnized rocks occasionally contain scheelite grains. Siderite also occurs in sandstone and slate. Mineralogy and textures of the siderostone suggest that it might be formed in the shallow marine basin where enough organic matter was present to maintain a low Eh and iron was supplied, and that siderite might be formed largely by diagenesis from iron-rich berthierine mud.

• Applied Biological Chemistry
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• v.35 no.2
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• pp.76-81
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• 1992

The technicals of KC-7079, isoprothiolane, perfluidone and tricyclazole were granulated with a mixture of inorganic carrier and oil-soluble binder, that is, stearly alcohol or ethyl cellulose. The concentration of the released active ingredient from the granules was analyzed at several days intervals after immersion of these granules in water at $25^{\circ}C$. At the content of stearyl alcohol less than $80g\;kg^{-1}$, the granule kneaded with stearyl alcohol mixture and water disintegrated in water. But the granule kneaded with methanol disintegrated in water at the content of stearyl alcohol less than $30g\;kg^{-1}$. The less the KC-7079-stearyl alcohol granule disintegrated, the slower the release rate of KC-7079 was. No matter how was increased the stearyl alcohol content, the release rate of KC-7079 granule which did not disintegrate was not significantly changed. The sustained releasing effect of the granules was little in the other three pesticides of which the water solubility was higher than of KC-7079(21 ppm). The granule made of ethyl cellulose did not disintegrate even at $5g\;kg^{-1}$ of ethyl cellulose. With the increase of ethyl cellulose content and the decrease of active ingredient in the granules, the sustaining effect of the granules on releasing acitive ingredient was increased. The lower the water solubility of pesticide was, the release rate tended to be sustained except perfluidone.

• Journal of Acupuncture Research
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• v.18 no.2
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• pp.51-66
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• 2001

The purpose of this morphological studies was to investigate the central neural pathway projecting to the acupoints $B_{62}$ and $K_6$ using the neuroanatomical method following injection of transsynaptic neurotropic virus, pseudorabies virus(PRV-Ba and PRV-Ga) into the $B_{62}$ and $K_6$. After survival times of 96 hours following injection into the twenty rats with PRV-Ba(Bartha strain) and PRV-Ga(Bartha strain, ${\beta}$-galacidodase insertion). They were perfused, and their spinal cord and brain were frozen sectioned($30{\mu}m$). These sections were stained by X-gal histochemical and PRV immunohistochemical staining method, and observed with light microscope. The results were as follows : 1. In spinal cord, overlaped PRV-Ba and PRV-Ga labeled neurons projecting to the $B_{62}$ and $K_6$ were founded in thoracic, lumbar and sacral spinal segments. In thoracic spinal segments, Densely labeled areas were founded in lamina IV, V, VII(intermediolateral nucleus) and X areas. In lumbar segemnts, labeled areas were founded in lamina II, IV, V and X areas. In sacral spinal segments, labeled areas were founded in lamina IV, V and VI areas. 2. In brain, overlaped PRV-Ba and PRV-Ga labeled neurons projecting to the $B_{62}$ and $K_6$ were founded in the $A_1$ noradrenalin cells/$C_1$ adrenalin cells/caudoventrolateral reticular nucleus, rostroventrolateral reticular nuclens, nucleus tractus solitarius, area postrema, raphe obscurus nucleus, raphe paltidus nucleus, raphe magnus nucleus, lateral paragigantoceltular nucleus, lateral rcticular nucleus, gigantocellular nucleus, locus coeruleus, subcoeruleus nucleus, motor trigeminal nucleus, Kolliker-Fuse nucleus, $A_5$ cell group, central gray matter, oculomotor nerve, paraventricular hypothalamic nucleus, median eminence, amygdaloid nucleus, frontal cortex, forelimb area, hindlimb area, 1, 2 areas of parietal cortex and granular and agranular cortex. This results were suggest that overlaped PRV-Ba and PRV-Ga labeled areas projecting to the $B_{62}$ and $K_6$ may be related to the emotional relay pathway in the central autonomic center.

• Asian Journal of Turfgrass Science
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• v.20 no.2
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• pp.175-190
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• 2006

The term mycoherbicide started in 1970, but its interest heightened due to increase costs of chemical herbicides. A classical biocontrol agent is expected to become a permanent part of its new environment and do no harm to it. Contemporary biological control agent(BCA) must be produced by artificial culture and could be applied like chemical herbicides over weeds. BCA is different from the classical approach in that it released through natural spread. To date 26 species of fungi are used as classical BCA against 26 species of weeds in seven countries. There are a number of examples of pathogens attacking non-target plants. But through risk assessments which include understanding the taxonomy, biology and ecology, the target and non-target species, it will be safe to introduce of exotic pathogens to control weeds. But pathogens have not been successfully used in practice. Many mycoherbicides show potential in laboratories, but are ineffective in the field and not consistent from year to year or field to field. There is also a lack of understanding humidity, dew formation and temperature and their effects on suppression of weeds by plant pathogens. Potential pathogen must be selected as a BCA. Previous studies suggest that these pathogens must (1) produce abundant and durable inoculum in artifical culture, (2) be genetically stable and weed specific and (3) kill weeds in control. A granular preparation of mycoherbicide into sodium alginate is lighter than liquids and less bulky than organic matter. Gel forms have also been used.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.103-134
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• 1977

The physiological and biochemical role of potassium for upland crops according to recent research reports and the nutritional status of potassium in Korea were reviewed. Since physical and chemical characteristics of potassium ion are different from those of sodium, potassium can not completely be replaced by sodium and replacement must be limited to minimum possible functional area. Specific roles of potassium seem to keep fine structure of biological membranes such as thylacoid membrane of chloroplast in the most efficient form and to be allosteric effector and conformation controller of various enzymes principally in carbohydrate and protein metabolism. Potassium is essential to improve the efficiency of phoro- and oxidative- phosphorylation and involve deeply in all energy required metabolisms especially synthesis of organic matter and their translocation. Potassium has many important, physiological functions such as maintenance of osmotic pressure and optimum hydration of cell colloids, consequently uptake and translocation of water resulting in higher water use efficiency and of better subcellular environment for various physiological and biochemical activities. Potassium affects uptake and translocation of mineral nutrients and quality of products. potassium itself in products may become a quality criteria due to potassium essentiality for human beings. Potassium uptake is greatly decreased by low temperature and controlled by unknown feed back mechanism of potassium in plants. Thus the luxury absorption should be reconsidered. Total potassium content of upland soil in Korea is about 3% but the exchangeable one is about 0.3 me/100g soil. All upland crops require much potassium probably due to freezing and cold weather and also due to wet damage and drought caused by uneven rainfall pattern. In barley, potassium should be high at just before freezing and just after thawing and move into grain from heading for higher yield. Use efficiency of potassium was 27% for barley and 58% in old uplands, 46% in newly opened hilly lands for soybean. Soybean plant showed potassium deficiency symptom in various fields especially in newly opened hilly lands. Potassium criteria for normal growth appear 2% $K_2O$ and 1.0 K/(Ca+Mg) (content ratio) at flower bud initiation stage for soybean. Potassium requirement in plant was high in carrot, egg plant, chinese cabbage, red pepper, raddish and tomato. Potassium content in leaves was significantly correlated with yield in chinese cabbage. Sweet potato. greatly absorbed potassium subsequently affected potassium nutrition of the following crop. In the case of potassium deficiency, root showed the greatest difference in potassium content from that of normal indicating that deficiency damages root first. Potatoes and corn showed much higher potassium content in comparison with calcium and magnesium. Forage crops from ranges showed relatively high potassium content which was significantly and positively correlated with nitrogen, phosphorus and calcium content. Percentage of orchards (apple, pear, peach, grape, and orange) insufficient in potassium ranged from 16 to 25. The leaves and soils from the good apple and pear orchards showed higher potassium content than those from the poor ones. Critical ratio of $K_2O/(CaO+MgO)$ in mulberry leaves to escape from winter death of branch tip was 0.95. In the multiple croping system, exchangeable potassium in soils after one crop was affected by the previous crops and potassium uptake seemed to be related with soil organic matter providing soil moisture and aeration. Thus, the long term and quantitative investigation of various forms of potassium including total one are needed in relation to soil, weather and croping system. Potassium uptake and efficiency may be increased by topdressing, deep placement, slow-releasing or granular fertilizer application with the consideration of rainfall pattern. In all researches for nutritional explanation including potassium of crop yield reasonable and practicable nutritional indices will most easily be obtained through multifactor analysis.