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The Concentration and Input/Output of Nitrogen and Phosphorus in Paddy Fields (논에서의 질소 및 인의 농도와 유출입)

  • Shin, Dong-Seok;Kwun, Soon-Kuk
    • Korean Journal of Environmental Agriculture
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    • v.9 no.2
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    • pp.133-141
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    • 1990
  • For the purpose of evaluating nutrient loadings into rivers and lakes from agricultural land, especially from paddy fields and also nutrient degradation in drainage channels, the Total Kjeldahl Nitrogen(TKN) and the Total Phosphorus(TP) were investigated in 29.5 ha. paddy fields in Hwa-Sung, Kyong-Ki, Korea, during the period from May 8, 1989 to Sep. 27, 1989. The results of the study can be su㎜arized as follows : 1. Annual inputs into paddy fields were 180 N-kg/ha 46 P-kg/ha. by fertilization, and 15.0 TKN-kg/ha. 10.0 TP-kg/ha. by irrigation, 8.0 TKN-kg/ha. 0.34 TP-kg/ha. by rainfall respectively. The amount of nutrient involved in surface runoff from paddies was 39.0 TKN-kg/ha. 9.2 TP-kg/ha. and in seepage 7.5 TKN-kg/ha. 2.1 TP-kg/ha. respectively 2. In WS1 stream(reach length equals 950m), nutrients decreased 0.31 TKN-mg/L/km, 0.01 TP-mg/L/km and in WS2 stream (reach length equals 750m) which are more meandering and undulating than WS1, the nutrients decreased 0.84 TKN-mg/L/km, 0.11 TP-mg/L/km. From these results, it was concluded that low stream velocity due to meandering and undulation promotes more degradation of nutrient concentrations. 3. For the purpose of decreasing nutrient loads from paddy fields, the amount of fertilizer used needs to be controlled, irrigation weirs need to be constructed in the drainage channels to delay the transportation of nutrients by decelerating the stream velocity and plants such as plantain-lily need to be cultivated in the channel to consume nutrients and therefore enlarge chances of self-purification.

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Antioxidant and Inhibitory Effects of Korean Panax ginseng Extract on Pro-inflammatory Mediators in LPS-stimulated RAW264.7 Macrophages (산양삼(Korean Panax ginseng) 추출물의 항산화 효과 및 LPS로 염증이 활성화된 RAW 264.7 대식세포에서의 염증매개물질 억제효과)

  • Kim, Ye-Jin;Son, Dae-Yeul
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.10
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    • pp.1371-1377
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    • 2012
  • Biological activities of Korean Panax ginseng 55% ethanol extract (KPGE) were investigated. The measured total polyphenol content of KPGE was 357.45 mg/100 g. KPGE showed the highest ${\alpha},{\alpha}$-diphenyl-${\beta}$-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) radical scavenging activities of 80% and 86% at 1,000 ${\mu}g/mL$, respectively. DPPH and ABTS radical scavenging activities significantly increased in a KPGE concentration-dependent manner. SOD-like activity of KPGE (1, 10, and 100 ${\mu}g/mL$) increased from 22% up to 33% at KPGE concentrations of 500 and 1,000 ${\mu}g/mL$. KPGE treatment significantly suppressed the generation of pro-inflammatory mediators, including nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), and cytokines (tumor necrosis factor-alpha: TNF-${\alpha}$, interleukin-6: IL-6, interleukin-$1{\beta}$: IL-$1{\beta}$), in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. KPGE demonstrated strong anti-inflammatory activity that reduced NO and $PGE_2$ production in LPS-stimulated RAW 264.7 cells. Even low concentrations of KPGE (1 and 10 ${\mu}g/mL$) reduced $PGE_2$ and NO production in RAW 264.7 macrophages without LPS-stimulation, respectively. At concentrations of 100, 500, and 1,000 ${\mu}g/mL$, TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 production were significantly suppressed. The results of our study suggest the potential of Korean Panax ginseng as an excellent antioxidant substance for inhibiting inflammatory mediators. Therefore, Korean Panax ginseng (KPGE) may be used as a therapeutic approach to various inflammatory diseases.

Changes in Circulatory and Respiratory Activities Observed on Men in an Engine Room of a Navy Ship (함정 기관실내 활동의 순환 및 호흡 기능에 대한 영향)

  • Hyun, Kwang-Chul;Nam, Kee-Yong
    • The Korean Journal of Physiology
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    • v.1 no.2
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    • pp.199-213
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    • 1967
  • Circulatory and respiratory activities were observed in men exposed to the environment of engine room of a cruising Republic of Korea Navy ship and compared to the control values obtained in an ordinary laboratory room on land. The environment of an engine room of cruising navy ship was presumed to be a multiple stress acting on men. The environment of the engine room included high temperature $(35-42^{\circ}C)$, low relative humidity (20-38% saturation), vibration (about 7 cycles per second), rolling and pitching of ship and noises. Sixteen men were divided into two groups consisted of each 8 subjects. Subjects of sea duty group had experience of continuous on board duty averaging 3.5 years. Men of land duty group had no experience of on board activity. On land observations were made on one day prior to the boarding and leaving the port and four days after landing. In between observations in the engine room were made on the first, 5 th, 9 th, 12 th, and 14 th day of on board activity. The whole experimental period lasted for 20 days. Measurements on circulatory and respiratory parameters were at standing resting state (after 30 minutes standing in the case of on land study and 15 minutes in engine room study) and within one minute after cessation of on the spot running of which rhythm was 30/min. and lasted for 5 minutes. Oxygen consumption and pulmonary function test were done in the period of two minutes from the 3rd to 5th minutes of running. The following results were obtained. 1. Body temperature showed no change regardless of group difference or on land or on board measurements. 2. Pulse rate increased markedly after boarding the ship id both groups. Pulse rate increased from the first day on board at rest and after exercise as compared to the on land control value. This increase in pulse rate was more marked after exercise. Sea duty group showed less increase in pulse rate at rest than the land duty group. Standing and resting pulse rate of sea duty group on lam was 81 and increased to 87 at the 5th day on board and remained smaller than the land duty group throughout the period on board. Control standing and resting pulse rate of land duty group on land was 76 and reached 89 at the 9th day on board and thereafter decreased a little. Pulse rate of land duty group at rest on board remained greater than that of sea duty group throughout the period on board. 3. Systolic blood pressure of sea duty group increased after boarding the ship and remained higher than the control value on land. In the land duty group, however, systolic blood pressure decreased during the period on board the ship. Diastolic blood pressure decreased in both groups. 4. Resting breathing rate of land duty group increased and remained higher than the control value on land. In sea duty group, however, resting breathing rate showed a transient increase on the 1st day on board and decreased thereafter to the control value on land and kept the same level throughout the period of cruise. Absolute value of breathing rate in the sea duty group was greater than the land duty group both at rest and after exercise. 5. There was a lowering of breathing efficiency in both groups. Thus, increases in tidal volume and minute ventilation volume and decreases in maximum breathing capacity, vital capacity, capacity ratio and air velocity Index were observed after boarding the ship. An increase in ventilation equivalent was also observed in both groups. The lowering of breathing efficiency was more marked in the land duty group than the sea duty group. 6. Energy expediture increased in both groups during their stay on the ship and was more marked in the sea duty group. 7, Lactate concentration in venous blood at rest and after exercise increased after boarding the ship and no group difference was observed.

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Effect of DEHP Administration on Reproduction in Pregnant Mice Ⅱ. Effect of DEHP Administration on Reproductive Characteristic and Blood Components in Pups Born after DEHP Administration in Pregnant Mice (임신중인 생쥐에 DEHP 투여가 번식현상에 미치는 영향 Ⅱ. 임신중인 생쥐에 DEHP 투여가 자손의 번식특성과 혈액성분에 미치는 영향)

  • Park, Dong-Heon;Jang, Hyun-Yong;Park, Choon-Keun;Cheong, Hee-Tae;Kim, Choung-Ik;Yang, Boo-Keun
    • Development and Reproduction
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    • v.8 no.2
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    • pp.91-97
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    • 2004
  • The objective of this study was to assess that the effects of DEHP administration on reproductive characteristics and blood hematological and chemical values in pups born after DEHP administration in pregnant mice. DEHP was administrated to pregnant mice by intraperitoneally injection with 0, 0.5, 1.0 and 10.0mg/kg B.W, 5 times at 3 days interval from Day 1 to Day 16 in the gestation period. The body weight and reproductive organ weight(testis, epididymis and coagulating gland) in male pups on 45 day after birth was not affected in all experimental groups, but vesicular gland in DEHP groups was significantly lower than that of control group(P<0.05). The semen characteristics of male pups were not affected in DEHP treatment groups. The WBC, HB, HT, MCH and albumin values in male pups were not affected in all experimental groups, but RBC MCV, MCHC, PLT and total protein values were significantly different among the experimental groups(P<0.05). In female pups, the effects of DEHP administration were not affected the body and uterus weight, but the left ovary in 10.0mg DEHP group was significantly heavier than in control and 0.5mg DEHP group(P<0.05). The WBC, MCV, MCH, MCHC, PLT, albumin, BUN and total protein values in female were not different in all experimental groups. The RBC, HB and HT values were significantly different among the experimental gruop(P<0.05). The historical evaluation of testis in male pups that were grown to 45 days after birth was not different in all experimental groups. The ovary in female pups had many corpus luteum in 10.0mg DEHP group. The endometriosisi of uterus was significantly decreased in DEHP group. There results suggest that low concentration of DEHP administration in pup born after DEHP administration in pregnant mice was not affered on reproductive characteristic, but was affected on blood hematological and chemical values.

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Fenton-like Reaction for Treatment of Petroleum-Contaminated Silty Clay after Soil Washing Process (토양세척 후의 유류 오염 Silty Clay 처리를 위한 유사펜톤 산화반응)

  • So, Myung-Ho;Ha, Ji-Yeon;Yu, Jae-Bong;Kim, Chang-Gyun
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.1
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    • pp.1-8
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    • 2009
  • This research was performed to assess a Fenton-like oxidation using naturally present iron in the field to treat remained oils throughout silty clay residues which finally resided even after a series of soil washing process. Biodegradability was thus tested for reaction products to investigate a possible treatment of the Fenton-like oxidation coupled with a biological treatment process. For those purposes, two types of field soil samples (e.g., dewatered cake after conditioning with a polymer and not-dewatered residue) were tested to remove TPH by adding the various concentration of hydrogen peroxide ($H_2O_2$). Moreover the biodegradability of treated samples was observed based on the ratio of $BOD_5/COD_{Cr}$ after Fenton-like oxidation. The Highest removal of TPH was at 1% of hydrogen peroxide ($H_2O_2$) when hydrogen peroxide ($H_2O_2$) was continuously injected for a period of time rather than that of spot introduction with the same amount of it. For the dewatered cake, TPH was effectively treated when the ratio of solid and water was mixed at 1 : 2. Employing cooking oil could increase solubility of TPH due to enhanced surface-active escalating TPH desorption from silty clay. Nonetheless, the biodegradability was decreased as long as the oxidation duration being extended regardless of operational conditions. It was therefore proved that Fenton-like oxidation using $H_2O_2$ and natural iron minerals was able to remove adsorbed oils in silty clay but the removal efficiency of TPH was low. And if a biological treatment process followed after Fenton-like oxidation, microorganisms would need enough time for acclimation.

Evaluation of Thermal Catalytic Decomposition of Chlorinated Hydrocarbons and Catalyst-Poison Effect by Sulfur Compound (염소계 탄화수소의 열촉매 분해와 황화합물에 의한 촉매독 영향 평가)

  • Jo, Wan-Kuen;Shin, Seung-Ho;Yang, Chang-Hee;Kim, Mo-Geun
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.5
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    • pp.577-583
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    • 2007
  • To overcome certain disadvantages of past typical control techniques for toxic contaminants emitted from various industrial processes, the current study was conducted to establish a thermal catalytic system using mesh-type transition-metal platinum(Pt)/stainless steel(SS) catalyst and to evaluate catalytic thermal destruction of five chlorinated hydrocarbons[chlorobenzene(CHB), chloroform(CHF), perchloroethylene (PCE), 1,1,1-trichloroethane(TCEthane), trichloroethylene(TCE)]. In addition, this study evaluated the catalyst poison effect on the catalytic thermal destruction. Three operating parameters tested for the thermal catalyst system included the inlet concentrations, the incineration temperature, and the residence time in the catalyst system. The thermal decomposition efficiency decreased from the highest value of 100% to the lowest value of almost 0%(CHB) as the input concentration increased, depending upon the type of chlorinated compounds. The destruction efficiencies of the four target compounds, except for TCEthane, increased upto almost 100% as the reaction temperature increased, whereas the destruction efficiency for TCEthane did not significantly vary. For the target compounds except for TCEthane, the catalytic destruction efficiencies increased up to 30% to 97% as the residence time increased from 10 sec to 60 sec, but the increase of destruction efficiency for TCEthane stopped at the residence time of 30 sec, suggesting that long residence times are not always proper for thermal destruction of VOCs, when considering the destruction efficiency and operation costs of thermal catalytic system together. Conclusively, the current findings suggest that when applying the transition-metal catalyst for the better destruction of chlorinated hydrocarbons, VOC type should be considered, along with their inlet concentrations, and reaction temperature and residence time in catalytic system. Meanwhile, the addition of high methyl sulfide(1.8 ppm) caused a drop of 0 to 50% in the removal efficiencies of the target compounds, whereas the addition of low methyl sulfide (0.1 ppm), which is lower than the concentrations of sulfur compounds measured in typical industrial emissions, did not cause.

Effects of Different Media and Oxygen Concentrations on In Vitro Maturation and Development of Porcine Follicular Oocytes (배양액과 산소농도가 돼지난포란의 체외성숙과 배발달에 미치는 영향)

  • 천행수;한만희;김종화;박병권;이규승;서길웅
    • Reproductive and Developmental Biology
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    • v.28 no.2
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    • pp.119-126
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    • 2004
  • The present study was carried out to examine the effect of four different media (NCSU (North Carolina State University)-23, PZM (Porcine Zygotes Medium)-3, PZM-4 and TCM (Tissue Culture Medium)-l99) and two oxygen concentrations (39 , 5% $O_2$, 5% $CO_2$ and 90% $N_2$, 5% $CO_2$ in air) on in vitro production of porcine IVM/IVF embryos. The results were summarized as follows: The rates of GVBD and nuclear maturations were not significantly different (p>0.05) for 44 hours of culture with four media in two oxygen concentrations. The rates of polyspermy, penetrated sperm(s) and male and female prouclei formation were not significantly different (p>0.05). among four media in two oxygen concentrations. The cleavage rates were not significantly different (p>0.05) among four media in two oxygen concentrations. At day 7 under gas atmosphere of 5% $O_2$, 5% $CO_2$ and 90% $N_2$, the blastocyst formation was significantly higher (p<0.05) in PZM-3 (19.9$\pm$2.4) than other media. Also, NCSU-23 medium gave high rate of blastocyst formation at day 7 under gas atmosphere of 5% $CO_2$ in air (p<0.05). Based on the result of differential staining of porcine blastocyst at dat 7, inner cell mass cell and total cell numbers were not significantly different (p>0.05) among four media in two oxygen concentrations. However, the observed total cell number was higher in PZM-3 medium (36.8$\pm$6.5) than other madia. In conclusion, these results suggested that in vitro production of porcine embryos in PZM-3 medium under a gas atmosphere of 5% $O_2$, 5% $CO_2$ and 90% $N_2$ was effective on the blastocyst formation rate and total blastocyst cell number.

Effect of Sucrose and Polybrene on the Gene Transfer into Porcine Oocytes using Retroviral Vector (레트로 바이러스 벡터를 이용한 돼지난자에의 유전자 전이에 있어 Sucrose와 Polybrene의 효과)

  • Kim, . K.S.;M.S. Kwon;J.Y. Ju;Kim, K.S.;Kim, T.;Lee, H.T.;K.S. Chung
    • Korean Journal of Animal Reproduction
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    • v.26 no.2
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    • pp.153-163
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    • 2002
  • In vitro matured porcine oocytes have very small volume of perivitellinspace (PVS). In these respect, the effect of sucrose and polybrene on the efficiency of gene transfer was investigated. As a gene (hGH) transfer vehicle, vesicular stomatitis virus glycoprotein pseudotyped retroviral vector (VSV-G) was used. Sucrose treatment has no detrimental effect on the rates of cleavage and resulted in the enlargement of PVS for the efficient introduction of retroviral vector stocks. Introduction rates of retrovirus in 0.5, 1, 2, 3 % sucrose treatment group were higher than that of the non-treatment group (39.3, 43.3, 35.7, 40.7 % vs. 8.3 %), respectively. In addition, we observed that sucrose pretreatment during injection procedure significantly reduce the frequency of polyspermy. In general, polybrene is a polycation essential for retrovirus transduction. The groups with the addition of 0.5, 5, 50$\mu\textrm{g}$/$m\ell$ polybrene exhibited a significant effect on gene transfer compared to that of the non-addition group (56.5, 50.0, 57.1 % vs. 34.6 %), respectively But, when the oocytes were co-injected with retrovirus and 50$\mu\textrm{g}$/$m\ell$ polybrene, the rates of cleavage and blastocyst development were 43.3 and 4.6%, respectively. This rates were lower than those of the non-addition group (70.0 and 17.3 %). In conclusion, sucrose pretreatment have increased efficiency of retroviral mediated gene transfer in porcine oocytes with no damage on in vitro fertilization and embryo development. In addition, sucrose pretreatment was beneficial in polyspermy inhibition. Presence of polybrene during microinjection showed a beneficial effect on the gene transfer in porcine oocytes, in low concentration. And these results will provide an useful tool for production of transgenic pigs by retroviral mediated gene transfer.

Selection of fungicides to control leaf spot of jujube (Zizyphus jujuba) trees caused by Phoma sp. (Phoma sp.에 의한 대추나무 점무늬병 방제용 살균제 선발)

  • Lee, Bong-Hun;Lim, Tae-Heon;Cha, Byeong-Jin
    • The Korean Journal of Pesticide Science
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    • v.4 no.3
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    • pp.40-46
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    • 2000
  • To select the effective fungicides for the control of leaf spot disease of jujube tree (Zizyphus jujuba) caused by Phoma sp., inhibitory effects of 26 fungicides for mycelial growth were investigated at $250{\mu}g\;a.i./m{\ell}$. In the test, eight fungicides were selected and minimum inhibitory concentration (MIC) for mycelial growth and an inhibitory effect for spore germination were investigated. Among the fungicides, myclobutanil, hexaconazole, and triflumizole were excluded in control effect tests because of their relatively high MICs. MICs were ranged $10-50{\mu}g\;a.i./m{\ell}$ for benomyl, carbendazim + kasugamycin (CK), and thiophanate-methyl. triflumizole (TT), and $50-250{\mu}g\;a.i./m{\ell}$ for iprodione + propineb (IT) and iminoctadine-triacelate (IT). However, benomyl and IP showed very low inhibitory effect on conidial germination. When the fungicides were sprayed on the seedlings before the leaves were inoculated with conidial suspension of Phoma sp., the protective values of CK and TT were around 70% at 1,000 ppm and around 90% at 2,000 ppm. The protective values were around 70% at 2,000 ppm (benomyl), 4,000 ppm (IP), and 8,000 ppm (IT). When the fungicides were sprayed after inoculation, benomyl showed the highest curative values of over 90% at 1,000 ppm and the values of CK and TT ranged $70{\sim}80%$ at 1,000 ppm. However, IP and IT had little or no effect on therapy of the disease. IT caused necrotic phytotoxicity on the leaves of jujube seedlings. As results, the best fungicides for the protection of jujube trees from leaf spot disease were CK (2,000 ppm) and TT (2,000 ppm) and for the remedy of the tree, benomyl (1,000 ppm) was the best. Therefore, alternate application of benomyl and CK or TT will be effective in the disease control.

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Characterization of Cement Solidification for Enhancement of Cesium Leaching Resistance (세슘 침출 저항성 증진 시멘트 고화체의 제조 및 특성 평가)

  • Kim, Gi Yong;Jang, Won-Hyuk;Jang, Sung-Chan;Im, Junhyuck;Hong, Dae Seok;Seo, Chel Gyo;Shon, Jong Sik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.2
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    • pp.183-193
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    • 2018
  • Currently, the Korea Atomic Energy Research Institute (KAERI) is planning to build the Ki-Jang Research Reactor (KJRR) in Ki-Jang, Busan. It is important to safely dispose of low-level radioactive waste from the operation of the reactor. The most efficient way to treat radioactive waste is cement solidification. For a radioactive waste disposal facility, cement solidification is performed based on specific waste acceptance criteria such as compressive strength, free-standing water, immersion and leaching tests. Above all, the leaching test is important to final disposal. The leakage of radioactive waste such as $^{137}Cs$ causes not only regional problems but also serious global ones. The cement solidification method is simple, and cheaper than other solidification methods, but has a lower leaching resistance. Thus, this study was focused on the development of cement solidification for an enhancement of cesium leaching resistance. We used Zeolite and Loess to improve the cesium leaching resistance of KJRR cement solidification containing simulated KJRR liquid waste. Based on an SEM-EDS spectrum analysis, we confirmed that Zeolite and Loess successfully isolated KJRR cement solidification. A leaching test was carried out according to the ANS 16.1 test method. The ANS 16.1 test is performed to analyze cesium ion concentration in leachate of KJRR cement for 90 days. Thus, a leaching test was carried out using simulated KJRR liquid waste containing $3000mg{\cdot}L^{-1}$ of cesium for 90 days. KJRR cement solidification with Zeolite and Loess led to cesium leaching resistance values that were 27.90% and 21.08% higher than the control values. In addition, in several tests such as free-standing water, compressive strength, immersion, and leaching tests, all KJRR cement solidification met the waste acceptance or satisfied the waste acceptance criteria for final disposal.