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Comparison of Liver, Kidney, Bone Metal Concentration in OhJeokSan-Treated Rats (오적산(五積散)을 투여한 흰쥐의 간장, 신장, 골중 금속농도 비교에 관한 연구)

  • Park Chul-Soo;Lee Sun-Dong;Park Hae-Mo;Park Yeong-Chul
    • Journal of Society of Preventive Korean Medicine
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    • v.6 no.2
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    • pp.66-85
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    • 2002
  • Traditional herbal medicine is used extensively among the Korean populations, and other Asian countries employ similar therapies as well In recent years, extensive focus was laid on adulteration of the herbal medicine with heavy metals. This may be mainly due to a soil contamination by an environmental pollution. The objective of this study is to identify the contents of various heavy metals in the blood from OhJeokSan-Decoction (OD) treated-rats. For this study, 13 kinds of metals including essential and heavy metals, i.e. Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se and Zn were analyzed by a slight modification of EPA methods and the following results are obtained. ; 1. There is no significant difference between the OD-treated groups and control group in liver, kidney, bone, brain, weight, food intake. 2. The amount of each metal analyzed in the liver are as follows; Al ; $0.235{\sim}4.215mg/kg$, As ; $0.103{\sim}0.461mg/kg$, Cd ; $0.005{\sim}0.010mg/kg$, Co ; $0.017{\sim}0.046mg/kg$, Cr ; $0.137{\sim}0.403mg/kg$, Cu ; $1.736{\sim}4.827mg/kg$, Fe ; $54.472{\sim}381.447mg/kg$, Hg ; not detected, Mn ; $1.159{\sim}2.803mg/kg$, Ni ; $0.007{\sim}0.095mg/kg$, Pb ; not detected, Se ; $0.682{\sim}1.887mg/kg$, Zn ; $10.213{\sim}26.119mg/kg$, by groups, respectively. In control and other experimental group, several metal (Co, Cu, Mn, Zn, As, Cr) has a significant difference, but in experimental I and other experimental II, III, IV, V groups, there are no significant difference. 3. The amount of each metal analyzed in the kidney are as follows; Al ; $1.712{\sim}31.230mg/kg$, As ; $0.062{\sim}0.439mg/kg$, Cd ; $0.010{\sim}0.062mg/kg$, Co ; $0.000{\sim}0.101mg/kg$, Cr ; $0.125{\sim}0.636mg/kg$, Cu ; $3.385{\sim}12.502mg/kg$, Fe ; $41.148{\sim}99.709mg/kg$, Hg ; $0.000{\sim}0.270mg/kg$, Mn ; $0.433{\sim}2.301mg/kg$, Ni ; $0.000{\sim}0.221mg/kg$, Pb ; $0.000{\sim}0.584mg/kg$, Se ; $0.540{\sim}1.600mg/kg$, Zn ; $8.775{\sim}17.060mg/kg$, by groups, respectively. The concentration of Cu, Se, Cr, and Hg are variated significantly in control and other experimental group, and Cu, Se, Cd, Cr are variated significantly in experimental I and other experimental II, III, IV, V groups. 4. The amount of each metal analyzed in the bone(tibia and fibula) are as follows; Al ; $9.557{\sim}119.464mg/kg$, As ; $0.139{\sim}12.250mg/kg$, Cd ; $0.000{\sim}0.295mg/kg$, Co ; $0.022{\sim}0.243mg/kg$, Cr ; $0.239{\sim}1.999mg/kg$, Cu ; $0.000{\sim}2.291mg/kg$, Fe ; $240.249{\sim}841.956mg/kg$, Hg ; $0.000{\sim}0.983mg/kg$, Mn ; $0.214{\sim}7.353mg/kg$, Ni ; $5.473{\sim}11.453mg/kg$, Pb ; $0.000{\sim}8.502mg/kg$, Se ; $0.000{\sim}3.005mg/kg$, Zn ; $61.158{\sim}195.038mg/kg$, by groups, respectively. The concentration of Se, Cd are variated significantly in control and other experimental groups, and Se is variated significantly in experimental I and other experimental II, III, IV, V groups. 5. Exceptionally several metal concentration is increased or decreased. but there is no significant harmful difference of metal concentration in the liver, kidney and bone, from the OD-treated-rats compared to those of the control group even if higher dosage($1{\sim}8$ times dosage of person) of OD was administered. Thus, it is expected that the herbal decoction in the traditional herbal medicine would not lay any burden on the body and the heavy metal toxins would not affect our physiological system. However, other kinds of herbal treatment, such as i.v. and i.p. should be considered in terms of metal toxicity in the body since the level of certain metal.

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Changes in Moisture Contents of Rice-hull Based Root Media and Growth Responses of 'Seolhyang' Strawberry during Vegetative Propagation (육묘 과정 중 포트에 충진된 팽연왕겨 혼합상토의 함수량 변화와 '설향' 딸기의 생장 반응)

  • Park, Gab Soon;Kim, Yeoung Chil;Ann, Seoung Won;Kang, Hee Kyoung;Choi, Jong Myung
    • Horticultural Science & Technology
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    • v.33 no.1
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    • pp.47-54
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    • 2015
  • This research was conducted to investigate the changes in moisture retention capacities of expanded rice-hull (ERH)-based root media and their influences on the growth of mother and daughter plants in vegetative propagation of 'Seolhyang' strawberry. The proportion of water at the container capacity of ERH medium was in the range of 20 to 23%. This range was lower than the 60 to 66% of strawberry-specialized medium, the 30 to 34% of soil mother material (SMM) and the 30 to 35% of loamy sand. The moisture content of ERH was reduced to 10 to 12% at 8 hours after irrigation, and there were large variations among replications of ERH medium. Among four kinds of root media formulated to contain ERH, the medium of ERH + coir dust (CD) (55 + 45%, v/v) had 26.5 and 32.5% water contents at 20 and 40 days after irrigation to daughter plants, respectively. The m edia o f ERH + sandy loam (S L) and E RH + S MM showed similar trends i n moisture r etention. The pH and EC i n the all root media tested were in the range of 6.7 to 7.1 and 0.03 to $0.08dS{\cdot}m^{-1}$, respectively. The pHs and ECs measured at 20 and 40 days after irrigation were not significantly different in each root medium. Among the root media formulated to contain ERH, the growth of daughter plants was the highest in the treatment of ERH + SL (55 + 45%, v/v). As the blending rate of coir dust was elevated in the ERH + CD media, moisture retention capacity increased gradually, but the growth of daughter plants became worse even though the medium showed higher moisture retention capacity than other root media tested. The growth of roots and aboveground tissues of daughter plants deteriorated in the root media formulated by blending ERH + perlite (PE) at various ratios. The results of this research suggest the optimum formulations of root media and management of moisture content in raising of strawberry daughter plants when ERH is a component of root media.

Manufacturing Fermented Rapeseed Meal Compost using Two Microbial Agents and the Effect of Their Application (유용 미생물 제제 이용 발효 유채박 비료 제조 및 시용 효과)

  • Lee, Ji-Eun;Park, Won;Kim, Kwang-Soo;Lee, Yong-Hwa;Kwon, Da-Eun;Moon, Youn-Ho;Cha, Young-Lok;Kang, Yong-Ku
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.1
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    • pp.55-62
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    • 2019
  • Rapeseed meal, which is a byproduct of rapeseed oil extraction, improves crop productivity by supplying nutrients to the soil. The present study aimed to manufacture fermented rapeseed meal compost using two effective microbial agents and evaluate their efficiency as fertilizer. To types of fermented rapeseed meal, manufactured using either a bio-carrier or microbial agent, showed no differences in pH, electrical conductivity (EC), and total nitrogen content. However, the contents of $NH_4-N$ and $NO_3-N$ as inorganic nitrogen were increased by 5.6 times and 1.5 times, respectively, after 5 d of fermentation. Rapeseed meal fermented for 5 d was applied to tomato a basal fertilizer and after eight weeks, the plant height increased in all fermented rapeseed treatments compared to that in the chemical fertilizer treatment, and also the quantum yield of photosystem II (PS II) showed the same trend. The total nitrogen content of tomato leaves treated with a microbial fermented rapeseed meal was twice as high as that of that treated with a chemical fertilizer. It was confirmed that the increase in the tomato height was an effect of the rapeseed meal containing inorganic nitrogen, which can easily be absorbed by plants. From these results, it is considered that fermented rapeseed meal manufactured with an effective microbial agent for 5 d showed the highest inorganic nutrient content and greatest growth enhancement in tomato.

Evaluations of Growth and Forage Quality of Sesbania Accessions Adaptable to Korean Environments (국내적응 세스바니아의 생육특성 및 사료가치 평가)

  • Lee, Chang Min;Kim, Young Jin;Ahn, Sol;Hailegioris, Daniel;Lee, Cheong Ae;Yun, Song-Joong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.64 no.3
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    • pp.278-286
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    • 2019
  • Sesbania, an annual herb, is known for its high forage value and salt tolerance. It has merits as a forage crop that is adaptable to reclaimed land in the Republic of Korea. Therefore, we collected Sesbania genetic resources from the Republic of Korea and other countries, and conducted experiments to evaluate their potential as a forage crop in Korean climate and soil conditions. In the preliminary experiments, 15 genetic resources which were able to set seeds in Korean environment were selected out of a total of 46 collected genetic resources. Among 15 genetic resources, SL13 was the tallest and it was followed by that of SC04, SR01 and SE07. The accessions with the earliest flowering started flowering 101 days after sowing and set seed in early August. Fifteen accessions were evaluated for their salt tolerance at germination stage based on germination rate and growth of germinated seedlings at 0 mM, 150 mM and 300 mM NaCl concentrations. Five genetic resources like SC04, SL13, SS20, SS24 and SR01 were selected to be tolerant to NaCl treatment. Forage value was evaluated based on crude protein, acid detergent fiber, neutral detergent fiber and in vitro dry matter digestibility. The forage value of leaves was significantly higher than that of stems, and the forage value of the stem was slightly better than that of rice straw. The forage value of leaves of all the genetic resources was higher than grade 1 by the American Forage and Grassland Council grade. Among five selected genetic resources, the relative feed value of SC04 was the highest and it was followed by that of SS20, SL13, SS24 and SR01.

Basic Studies of Korean Native Clerodendron trichotomum Thunberg for Landscape Uses (전통식물 누리장나무의 조경용 소재개발을 위한 기초연구)

  • Han, In-Song;Ha, Yoo-Mi;Kim, Dong-Yeob;Lee, Bong-Ha
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.2
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    • pp.130-138
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    • 2011
  • This study was carried out to investigate growth characteristics and propagation methods of Clerodendron trichotomum for landscape uses. The results are obtained as follows: In the first place, Korean native C. trichotomum was printed in the "Enumeration of plants in Chosun" in 1937 by Tae Hyun Chung. C. trichotomum is a shrub with round shape. This is noted for its late summer flowers, showy fruit and malodorous foliage. White flowers in long-peduncled cymes bloom in the upper leaf axils from late summer into fall. Flowers are followed by small bright blue fruits, each subtended by a fleshy red calyx. C. trichotomum showed high seed germination rate and greater shoot length in plug box than in normal seeding bed. The rooting rate of C. trichotomum according to cutting date was highest on July 7. The optimum date for cutting was on July 7~10 when the shoots were more hardened. Soil acidity ranged from pH 4.58 to 5.52. The most effective method for rooting of C. trichotomum was treatment with 1,000 ppm IBA on July 7 cuttings, which showed rooting rate of over 90%. Korean native C. trichotomum was successfully propagated through soft cutting and seed.

Conservation and Scientific Analysis of Human Bone Excavated in Sabi Period of Baekje from Eungpyeong-ri, Buyeo (부여 응평리 출토 백제 사비기 인골 보존처리 및 과학적 분석)

  • KIM, Mijeong;LEE, Yunseop;CHO, Eunmin;PARK, Sujin;MOON, Minseong
    • Korean Journal of Heritage: History & Science
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    • v.55 no.1
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    • pp.305-321
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    • 2022
  • The stone chamber tomb in Eungpyeong-ri, Buyeo, is a joint tomb that contains the bodies of two individuals. This paper investigates the relationship between the buried persons and the characteristics of the stone chamber tomb. Based on the geographical location, relics, and the excavated human bones, it was determined that the tomb was built during the Sabi Period of the Baekje Dynasty and that the buried individuals were most probably residents of high stature or government officials. To study the excavated bones, the remains were carefully collected and conservation was carried out. Before collecting samples from the human bones for the analytical research, the results of near-infrared analysis were used to collect the samples for the isotope analysis and DNA analysis. The most important issue when handling the excavation site was the reinforcing agent and the concentration of the agent used. In situations like this, Paraloid B-72 is the most suitable agent. When the shape of human bones was difficult to distinguish from the soil, conservation was performed using X-ray and CT imaging data. The same chemical used for the reinforcement of the site was used to complete a minimum level of conservation to the surface areas where the conservation treatment of removing foreign substances, the reinforcement areas, and bonded areas were carried out. The collagen yield from the sample obtained at selected position was 3.8% to 6.1%. The results of analyzing the stable isotopes of carbon and nitrogen found in the extracted collagen showed that the stable isotope ratios came out to δ13C -18.3‰±0.1‰, -19.0‰±0.1‰ for EBW and δ15N 10.7‰±0.5‰, 10.6‰±0.1‰ for EBE. It is believed the two individuals consumed small amounts of minor cereals, mainly from C3 plants, and protein was obtained from eating terrestrial animals. What's more, the deviations in data obtained from the two individuals were so small that it could be inferred that the individuals ate similar foods. Considering the preservation state of the sample, amplifying DNA for the DNA analysis would have been very difficult since the amount of surviving DNA was so deficient. For DNA analysis, it is anticipated that the results could be derived by applying improved extraction methods that will be developed in the future. In this research, any association between scientific analysis(DNA and stable isotope ratio) and near-infrared spectroscopy was difficult to establish. Further research is needed on the utilization of near-infrared analysis for gathering samples from human bones.

Experimental Study on Modular Community Planting for Natural Forest Restoration (자연림 복원을 위한 모듈군락식재 실험연구)

  • Han, Yong-Hee;Park, Seok-Gon
    • Korean Journal of Environment and Ecology
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    • v.36 no.3
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    • pp.338-349
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    • 2022
  • This study aims to investigate whether modular community planting, which entailed planting a variety of species of seedlings at high density, was more effective in restoring natural forests than the existing mature tree planting. We also investigated whether the planting density of the modular community planting facilitates growth or improves the tree layer coverage. We conducted outdoor experiments in which the samples were divided into a mature tree planting plot (control plot), where mature trees were planted at wide intervals, and a modular community planting (MCP) plot (treatment plot), where multiple seedlings were planted in high density. The MCP plot was further divided into the plot in which 3 seedlings were planted per m2 and the plot of 1 seedling per m2. We measured the specimens' survival rate, growth rate (tree height, crown width, and root collar diameter), and cover rate for 26 months from May 2019 and the predicted future tree height growth using the measured tree height. The survival rate and relative growth rate of the MCP were higher than those of the mature tree planting plot. The vertical coverage rate of the tree crown in the MCP exhibited complete coverage of the ground before 23 months, while the coverage rate of the mature tree planting decreased due to transplantation stress. The seedlings in the MCP, which were planted at high density, grew well and were predicted to grow higher than the mature trees in the large tree planting plot within 5 to 6.5 years after planting. It was due to multiple species, seedlings, high-density planting, and planting foundation improvements, such as soil enhancement and mulching. In other words, the seedlings planted in the MCP had a higher survival rate as their environmental adaptation after planting was better, and their early growth was also larger than the trees in the mature planting plot. The high-density mixed planting of various native species not only mitigated the inter-complementary environmental pressures but also facilitated growth by inducing competition between species. Moreover, the planting foundation improvement effectively increased the seedlings' viability and growth rate. A reduction in follow-up management costs is expected as the tree layer coverage sharply increases due to the higher planting density. In the MCP (3 seedlings per m2 and 1 seedling per m2), the tree height growth was promoted with the higher planting density, and the crown width and root collar diameter tended to be larger with the lower planting density, but these differences were not statistically significant.

Removal Velocities of Pollutants under Different Wastewater Injection Methods in Constructed Wetlands for Treating Livestock Wastewater (인공습지 축산폐수처리장에서 주입방법에 따른 오염물질의 제거속도 평가)

  • Kim, Seong-Heon;Seo, Dong-Cheol;Park, Jong-Hwan;Lee, Choong-Heon;Lee, Seong-Tea;Jeong, Tae-Uk;Kim, Hong-Chul;Ha, Yeong-Rae;Cho, Ju-Sik;Heo, Jong-Soo
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.2
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    • pp.272-279
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    • 2012
  • In order to effectively treat livestock wastewater in constructed wetlands by natural purification method, removal velocities of pollutants under different injection methods in constructed wetlands were investigated. The removal velocities of chemical oxygen demand (COD), suspended solid (SS), T-N and T-P by continuous injection method were slightly rapid than those by intermittent injection method in full-scale livestock wastewater treatment plant. The removal velocity (K; $day^{-1}$) of COD by continuous injection method was $0.38\;d^{-1}$ for $1^{st}$ bed, $0.13\;d^{-1}$ for $2^{nd}$ bed, $0.17\;d^{-1}$ for $3^{rd}$ bed, $0.05\;d^{-1}$ for $4^{th}$ bed and $0.17\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of COD in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.210\;d^{-1}$, $0.086\;d^{-1}$, $0.222\;d^{-1}$, $0.053\;d^{-1}$ and $0.137\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of SS by continuous injection method was $0.750\;d^{-1}$ for $1^{st}$ bed, $0.108\;d^{-1}$ for $2^{nd}$ bed, $0.120\;d^{-1}$ for $3^{rd}$ bed, $0.086\;d^{-1}$ for $4^{th}$ bed and $0.292\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of SS in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.485\;d^{-1}$, $0.056\;d^{-1}$, $0.174\;d^{-1}$, $0.081\;d^{-1}$ and $0.227\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of T-N by continuous injection method was $0.361\;d^{-1}$ for $1^{st}$ bed, $0.121\;d^{-1}$ for $2^{nd}$ bed, $109\;d^{-1}$ for $3^{rd}$ bed, $0.047\;d^{-1}$ for $4^{th}$ bed and $0.155\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of T-N in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.235\;d^{-1}$, $0.071\;d^{-1}$, $0.171\;d^{-1}$, $0.058\;d^{-1}$ and $0.126\;d^{-1}$, respectively. The removal velocity (K; $day^{-1}$) of T-P by continuous injection method was $0.803\;d^{-1}$ for $1^{st}$ bed, $0.084\;d^{-1}$ for $2^{nd}$ bed, $0.076\;d^{-1}$ for $3^{rd}$ bed, $0.118\;d^{-1}$ for $4^{th}$ bed and $0.301\;d^{-1}$ for $5^{th}$ bed. The removal velocities (K; $day^{-1}$) of T-P in $1^{st}$, $2^{nd}$, $3^{rd}$, $4^{th}$ and $5^{th}$ beds by intermittent injection method were $0.572\;d^{-1}$, $0.049\;d^{-1}$, $0.090\;d^{-1}$, $0.112\;d^{-1}$ and $0.222\;d^{-1}$, respectively.

Studies on the Foliar Application of Urea as Nitrogen Source of Rice Plant Nutrition (요소엽면살포(尿素葉面撒布)에 따른 수도(水稻)의 질소영양(窒素營養)에 관(關)한 연구(硏究))

  • Cho, Seoung-Jin
    • Applied Biological Chemistry
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    • v.9
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    • pp.125-147
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    • 1968
  • This experiment was carried out as a part of the studies on reasonable application of nitrogen in rice plant to determine: (I) Nitrogen absorption. and rooting of rice seedlings as affected by urea foliar application at late seedling stage (II) Effect of leaf prunning and foliar application of urea at late heading stage on the maturation and yield of rice (III) Effect of foliar application of urea and its time during the stage of ear formation on yield of rice plant. Results obtained are summarized as follows. Exp.I: Nitrogen absorption and rooting of rice seedlings as affected be urea foliar application at late seedling stage. 1 : The foliar application of urea plots$(T_{1},T_2)$ snowed mare N-content than non-urea foliar application plot(T0) at lane seedling stage, being significant among treatments and foliar application of urea seemed more effective in increasing the N-content of seedlings. and promoted root settlement and early growth alter the transplanting. 2 : The carbon contents of the plants of $T_1$, and $T_2$ at late seedling stage increased than T0, and the carbon contents. of $T_1$ and $T_2$ plots became higher in amount in proportion to the nitrogen absorption as compared with those of $T_0$. 3 : C/N ratio appeared significant among soil application plots($N_1, \;N_2$) and foliar application of urea plots ($T_1$, $T_2$ and $T_0$). C/N ratio was lower in case of increased amount of nitrogen. The higher contents of nitrogen and carbon and lower C/N ratio resulted in the increment of root numbers and root lengths. Exp.II: Effect of leaf prunning and foliar application of urea at late heading stage on the maturation and yield of rice. 1 : There was a highly significant decrease in the maturing rate by severe leaf prunning. In the mean time, significant increase in maturing rate was observed with urea foliar application and it was found the more frequent application the more effective for higher maturing rate with a moderate significance. A correlationship between the level of prunning and maturing rate was enumerated to 0.961 of correlation coefficient, which indicated an increased maturing rate by the increased number of remaining leaves. 2 : The 1.000 grain weight, grain weight and hulled rice yield increased by leaf prunning in order (plot a$A_1$, $A_3$, $A_2$ and $A_0$ were 89.8%, 89.4%, 87.8% and 87.5% respectively, showing the highest of rate in $A_1$ and $A_3$ in methods of ear fertilization and being highly significant between its treatment. 3 : 1000 grain weights were highly significant between time of application, showing a tendency of increase of weights with the time lagging until days before earings as that of maturing rates. High significance was recognized between methods of ear fertilization, showing the highest in $A_2$ 23.18 gr. 4 : Yields per $3.3m^2$ were not significant between time of ear fertilization, whereas were highly significant between methods of ear fertilization. Those of $A_1$, $A_3$, $A_2$ and $A_0$ were 1.486 kg, 1.491 kg, 1.381 kg and 1.328 kg, respectively, showing the highest in $A_1$ and $A_3$. 5 : Hulling ratios showed significant different between time of ear fertilization, showing the highest in $T_2$, whereas those of methods of ear fertilization were highly significant between its treatment, Those of $A_1$, $A_3$, $A_2$ and $A_0$ were 84.72%, 84.06%, 83.29%, and 82.56% respectively, showing the highest m $A_2$ and $A_3$ among others. 6 : Yields of hulled rice per $3.3m^2$ showed significant different between time of ear fertilization, showing the highest in $T_1$ 1.192 kg. Whereas, those were highly significant between methods of ear fertilization. Those of $A_1$, $A_3$, $A_2$ and $A_0$ were 1.259 kg, 1.254 kg, 1.149 kg and 1.095 kg, respectively, showing the highest in $A_1$ and $A_2$. 7 : Contents of nitrogen on rice plant increased in case of nitrogen application as ear fertilizer and showed that the case of urea foliar application was more effective than that of soil application, showing the increased nitrogen content of rice plant was accompanied by carbon content.

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Adsorption of Arsenic onto Two-Line Ferrihydrite (비소의 Two-Line Ferrihydrite에 대한 흡착반응)

  • Jung, Young-Il;Lee, Woo-Chun;Cho, Hyen-Goo;Yun, Seong-Taek;Kim, Soon-Oh
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.3
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    • pp.227-237
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    • 2008
  • Arsenic has recently become of the most serious environmental concerns, and the worldwide regulation of arsenic fur drinking water has been reinforced. Arsenic contaminated groundwater and soil have been frequently revealed as well, and arsenic contamination and its treatment and measures have been domestically raised as one of the most important environmental issues. Arsenic behavior in geo-environment is principally affected by oxides and clay minerals, and particularly iron (oxy)hydroxides have been well known to be most effective in controlling arsenic. Among a number of iron (oxy)hydroxides, for this reason, 2-line ferrihydrite was selected in this study to investigate its effect on arsenic behavior. Adsorption of 2-line ferrihydrite was characterized and compared between As(III) and As(V) which are known to be the most ubiquitous species among arsenic forms in natural environment. Two-line ferrihydrite synthesized in the lab as the adsorbent of arsenic had $10\sim200$ nm for diameter, $247m^{2}/g$ for specific surface area, and 8.2 for pH of zero charge, and those representative properties of 2-line ferrihydrite appeared to be greatly suitable to be used as adsorbent of arsenic. The experimental results on equilibrium adsorption indicate that As(III) showed much stronger adsorption affinity onto 2-line ferrihydrite than As(V). In addition, the maximum adsorptions of As(III) and As(V) were observed at pH 7.0 and 2.0, respectively. In particular, the adsorption of As(III) did not show any difference between pH conditions, except for pH 12.2. On the contrary, the As(V) adsorption was remarkably decreased with increase in pH. The results obtained from the detailed experiments investigating pH effect on arsenic adsorption show that As(III) adsorption increased up to pH 8.0 and dramatically decreased above pH 9.2. In case of As(V), its adsorption steadily decreased with increase in pH. The reason the adsorption characteristics became totally different depending on arsenic species is attributed to the fact that chemical speciation of arsenic and surface charge of 2-line ferrihydrite are significantly affected by pH, and it is speculated that those composite phenomena cause the difference in adsorption between As(III) and As(V). From the view point of adsorption kinetics, adsorption of arsenic species onto 2-line ferrihydrite was investigated to be mostly completed within the duration of 2 hours. Among the kinetic models proposed so for, power function and elovich model were evaluated to be the most suitable ones which can simulate adsorption kinetics of two kinds of arsenic species onto 2-line ferrihydrite.