• 한국초지조사료학회지
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• 제40권1호
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• pp.37-43
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• 2020

This study was conducted to evaluate the effects of different nitrogen levels on the yield and nutrient quality of a newly developed domestic hybrid of Teosinte, Geukdong 6〔Zea mays L. subsp. mexicana (Schrad.) H. H. Iltis〕. The field experiment was conducted in a randomized block design with three replicates and consisted of four nitrogen (N) application rates, T1 (200 kg/ha), T2 (300 kg/ha), T3 (400 kg/ha), and T4 (500 kg/ha). No differences were found in plant length, leaf length, leaf width, leaf number, dead leaves, stem hardness, tiller number, and fresh yield (p>0.05). The T3 showed significantly greater dry matter yield at harvest (heading stage) compared to the other treatments (p<0.05). The crude protein content of T4 (10.49%) was higher than those of T1 and T2 (p<0.05). However, there was no significant difference between T4 (10.49%) and T3 (9.63%). The effects on crude fat, crude ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude fiber were not significant (p>0.05). The sugar content was higher in the T2 treatment than the other treatments (p<0.05). For Ca, T3 showed significantly greater content (p<0.05). However, no significant effects were found in the contents of Cu, Fe, K, Mg, Mn, Mo, and Zn (p>0.05). Na content was higher in order of T2 > T4 > T3 > T1 (p<0.05). Total mineral contents were not significantly different among the treatments (p>0.05). Given these results, we recommend the amount of nitrogen fertilization necessary for "Geukdong 6" to be around 400 kg per ha (T3), when considering, high fresh yield, dry matter yield, number of leaves and content of crude protein.

• 한국초지조사료학회지
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• 제16권4호
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• pp.299-306
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• 1996

This experiment was conducted from 1991 to 1993 at the forage experimental field, College of Agriculture and Life Sciences, SNU, Suweon to investigate the effects of previous crop residues on growth and yield of succeeding corn(2ea mays L.) and also to determine the best double cropping system necessary to maximize the total dry matter yield of winter forage crops plus corn for silage. In this experiment, treatments consisted of no crop as a control, late maturing Kodiak rye(Seca1e cereale L.), Bamapoli forage rape(Brassica napus Subsp. oleifera L.), G-sprinter oats(Avem sativa L.), Chief crimson clover(Trifolium incarnatum L.), Jackson Italian ryegrass(lo1ium rnultiJlorum L.), Vantage vetch(Vicia sativa L.) and early maturing Koolgrazer rye(Seca1e cereale L.). Corn leaf number and silking date were not significantly affected by previous crop residues, but the leaf number of corn following Italian ryegrass was reduced by 1.9 relative to no previous crop. The plant height and LA1 were significantly reduced during early development when corn followed Italian ryegrass and late maturing Kodiak rye (p<0.05). The dry matter and estimated TDN yields of corn were significantly reduced when corn followed Italian ryegrass and late maturing Kodiak rye. The yield reductions for corn following Italian ryegrass, late maturing Kodiak rye and early maturing Koolgrazer rye, relative to com when no previous crops were planted, were 34, 17 and 8%, respectively. Therefore, the reduction in corn growth and yield in this experiment could be explained by an allelopathic effect resulting from the Italian ryegrass and rye residues. The highest total dry matter yield of 30,509kg/ha was obtained from an early maturing rye-corn double cropping sequence in combination among the eight cropping systems.

• 한국초지조사료학회지
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• 제14권1호
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• pp.57-63
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• 1994

We use a variety of methods to determine the optimum time for havesting corn for silage. In addition, adequate dry matter for silage must be considered along with maturity stage. The objective of this study was to evaluate using the kernel milk line to determine when to harvest com for silage in 1992 on the Livestock Experimental F m , Keiymung Junior College at Keongsan, Keongsangbukdo. Four hybrids were field grown and com plants were harvested at various stages of kernel development so that kemel milk line movement could be analyzed whilc the corn was in the premature stages. As the plants approached maturity, the ears were collected from each of the hybrids and the position of the milk line wa5 noted. Then the whole plants were chopped and the content of DM was determined. The milk line was a readily identifiable feature of maturing com kemels. We focused on the five development \tage\. The fint was "soft dough". The second was "dent". The third wa, "75% milk". and the fourth wa5 "half milk". The half milk occurs when the milk line is positioned falf way down the kemel face. and the final stages win "no milk", milk disappearance as indicators of physiological maturity in maix. Milk free stage of the kemel occurred from I to 3 days prior to black layer having developed. The range for harvesting com for silage occurs a kemels mature from 75% milk to no milk. Position of milk line was easy to see. and can be used as a visible indicator to determine com matunty stage\ and whole plant dry matter. Whole plant dry matter increased with advancing maturity. averaged over hybrids it was 24.1, 25.6. 28.5. 34.6 and 39.0% at soft dough, dent, 75% milk. half milk and no milk. Milk line was more usehl indicator in monitoring corn maturity prior to physiological maturity.ing corn maturity prior to physiological maturity.

• Asian-Australasian Journal of Animal Sciences
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• 제18권2호
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• pp.214-220
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• 2005

The study was conducted to compare the dry matter intake and digestibility of Atriplex halimus (AH) and Atriplex nummularia (AN) and determine the proper proportion of saltbushes for partial replacement of alfalfa hay in the diets of Awassi sheep. The foliage of AH and AN were hand-plucked, air-dried in shade and then chopped mechanically similar to alfalfa hay. Two trials were conducted separately to determine voluntary feed intake and digestibility of saltbush browse. In the first trial, fifteen 8 month old Awassi lambs were distributed into 3 equal groups, and each animal was housed in individual pen. Each group received one of three dietary treatments: chopped alfalfa hay (H), dried foliage of Atriplex nummularia or foliage of Atriplex halimus. In the second trial, twentyseven 12 months old Awassi male lambs were randomly selected, distributed into nine equal groups, and housed into metabolic crates. Each group of animals received one of nine dietary treatments: alfalfa hay, AN, AH and different proportions (25, 50 and 75%) of AN or AH mixed with alfalfa hay. Forage type had a significant (p<0.001) effect on dry matter intake (DMI) and growth rate of lambs of the voluntary feed intake trial. Lambs receiving the alfalfa hay diet showed high DMI and high growth rate compared to those fed the diets containing saltbush. In the digestibility trial, dietary treatments had significant (p<0.05) effect on DMI, dry matter digestibility (DMD) (p<0.01) and organic matter digestibility (OMD) (p<0.01). The inclusion of AN in the diet up to 50% had no significant effect on DMI and DMD, whereas the inclusion of AH above 25% reduced DMI, DMD and OMD. The treatments had significant (p<0.05) effect on water intake and on live weight changes of lambs. Except for the diet containing 25% of AN browse, all lambs fed diets containing the saltbushes exhibited loss in body weight. The nutritive value of Atriplex nummularia foliage is better than that of A. halimus and it is possible to replace up to 50% of alfalfa hay by A. nummularia without negative effects on intake and digestibility of dry matter.

• 한국물환경학회지
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• 제26권6호
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• pp.969-975
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• 2010

Estimating the organic matter loadings from individual treated sewage has become important for establishment of effective management strategies to control refractory organic matter (R-OM) in watersheds. For this study, regression equations were constructed using treated sewage data to convert the chemical oxygen demand (COD) concentrations, which are mostly available from open database, into total organic carbon (TOC) and R-OM concentrations. Effluent samples were collected from five major sewage treatment plants (STPs) located upstream of the lake Paldang. Variations in the OM concentrations were not associated with either the location of the STP or the sampling season. The effluent investigated were characterized by higher ratio of R-OM with respect to biodegradable organic matter (B-OM) and higher presence of dissolved organic matters (DOM) versus particulate organic matter (POM). Compared to $COD_{Mn}$, $COD_{Cr}$ exhibited higher oxidation efficiencies and greater variations in the concentrations. The concentrations of $COD_{Mn}$ were positively correlated with dissolved organic carbon (DOC), total organic carbon (TOC), and R-OM concentrations. There was nearly no seasonal and annual variation in the regression equations between $COD_{Mn}$ and TOC or R-OM concentrations. The constructed regression equations for TOC and R-OM were $0.650({\pm}0.071){\times}COD_{Mn}+1.426({\pm}0.575)$ and $0.340({\pm}0.083){\times}COD_{Mn}+2.054({\pm}0.670)$, respectively. The established equations are expected to contribute to estimating OM loadings from the STPs into the lake Paldang and also to compensating for the deficiency of the data for effluent OM concentrations in STP.

• 한국토양비료학회지
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• 제8권1호
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• pp.19-23
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• 1975

답토양(畓土壤)에 유기물(有機物)을 연용(連用)함으로써 토양(土壤)의 이화학적성질(理化學的性質)에 미치는 영향(影響)을 구명(究明)하기 위(爲)하여 20년간(年間) 퇴비(堆肥)를 시용(施用)한 조립질토양(粗粒質土壤)의 시료(試料)를 채취(採取) 분석(分析)한 결과(結果)는 다음과 같다. 1. 립경조성(粒徑組成)은 퇴비연용구(堆肥連用區)와 무퇴비구간(無堆肥區間)에 차이(差異)가 없었으나 수리전도도(水理傳導度), 수중침정용적(水中沈定容積)은 퇴비연용구(堆肥連用區)에서 높았다. 2. 가비중(假比重), 토양경도(土壤硬度)는 퇴비연용구(堆肥連用區)에서 낮았으며 공극률(孔隙率)은 높았다. 3. Atterberg 상수(常數)(액성한계(液性限界), 소성한계(塑性限界) 및 소성지수(塑性指數))가 퇴비연용구(堆肥連用區)에서 높았다. 4. 립국분포(粒國分布)는 퇴비연용구(堆肥連用區)에서 뚜렷하게 증가(增加)되지 않았다. 5. pH, 유기물함량(有機物含量), 염기치환용량(鹽基置換用量), 치환성염류(置換性鹽類) 등(等)은 퇴비연용구(堆肥連用區)에서 근소(槿少)하게 높았다.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.676-680
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• 2004

Complexes M($C_7H_2NO_5)3H_2O{\cdot}H_2O{\cdot}0.25MeCN$ (M=Ni, Co) were crystallized from the reactions of $Ni(CH_3COO)_2{\cdot}4H_2O\;or\;Co(CH_3COO)_2{\cdot}2H_2O$ with KSCN and 2,6-dicarboxy-4-hydroxypyridine (chelidamic acid). The structures were characterized by X-ray crystallography. The crystal structures of 1 and 2 show a distorted octahedral coordination geometry around the M(II) ions, which are chelated by one nitrogen atom and two oxygen atoms of the chelidamic acid and three water molecules. Complexes 1 and 2 display the hydrogen-bonded 3D framework. The magnetic behavior of 2 exhibits antiferromagnetic interaction.

• 환경영향평가
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• 제8권1호
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• pp.81-92
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• 1999

This study discussed the appropriateness of organic matter indexes such as biochemical oxygen demand(BOD) and chemical oxygen demand with potassium permanganate($COD_{Mn}$) in water quality environmental standard of streams and lakes and the applicability of the items to water quality environmental standard to add or substitute COD with potassium dichromate ($COD_{Cr}$) and total organic carbon(TOC) being used as index of organic matter. And indexes of organic matter content and organic carbon concentration were distinguished between dissolved and particulate component in water sample to estimate their effect on pollutants loading in lake and stream. The ratio of $COD_{Cr}$/BOD was 5.1 under BOD concentration 3mg/L in river water quality environmental standard II, and 2.67 above it. This ratio was diminished to 2.04 when BOD concentration was more than 8mg/L, in river quality environmental standard IV. Also the ratio of $COD_{Mn}$/BOD showed 2.16 under 3mg/L(BOD), and 1.1 above it. This ratio is also diminished to 0.84 over 8mg/L(BOD). Accordingly, we should apply this ratio depending on the concentration level to add and change organic matter index of water quality environmental standard newly. The ratio $COD_{Cr}/COD_{Mn}$ both in lake and stream shows 2.37(r=0.986, p<0.001). But the ratios showed range of 2.34~2.50, which is no much difference of this ratio according to $COD_{Mn}$ concentration.

• 한국초지조사료학회지
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• 제42권3호
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• pp.176-182
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• 2022

The aim of this study was to investigate dry matter productivity and nitrate nitrogen content in the growth stages of barnyard millet (Echinochloa esculenta) cultivated for feed, which was treated with different nitrogen fertilization levels. An early variety of barnyard millet (cv. Shirohie) was used for the test, and the different treatments with nitrogen fertilizer were as follows: 50% (N-40 kg/ha, T1), 100% (N-80 kg/ha, reference amount, T2), 150% (N-120 kg/ha, T3), 200% (N- 160 kg/ha, T4), 250% (N-200 kg/ha, T5), and 300% (N-240 kg/ha, T6). Sowing was done on May 13, 2021 and plants were harvested for four stage; vegetative stage, elongation stage, heading stage, and milk stage. The length of the millet increased significantly as the amount of nitrogen fertilization increased during the harvest period (p<0.05), but the difference was insignificant during the milk stage (p>0.05). Moreover, barnyard millet dry matter yield increased significantly as the levels of nitrogen fertilization increased (p<0.05), but there was no significant difference in dry matter yield among nitrogen fertilization levels during the heading stage (p>0.05). Chlorophyll also was significantly higher in T5 (250%) at all harvesting times, whereas nitrate nitrogen content was highest at the vegetative stage, gradually decreased as growth progressed, and lowest at the milk stage. Finally, as the nitrogen fertilization levels increased, the nitrate nitrogen content was significantly higher in all treatment groups (p<0.05). Therefore, our results suggest that the most appropriate nitrogen fertilizer levels is between 150%-200%, considering the dry matter yield, feed ingredients and nitrate nitrogen content in barnyard millet for feed.

• 인간식물환경학회지
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• 제22권1호
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• pp.31-38
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• 2019

Experiments were carried out to investigate the effects of mosses on the removal of particulate matter (PM 10) and volatile organic compounds (VOCs) in an indoor space and on the composition of air. For particulate matter removal experiments, 0.2 g mosquitto coil was burned in a glass chamber, where three kinds of mosses (Plagiomnium cuspidatum, Myuroclada maximowiczii, Etodon luridus) were placed. For VOCs removal experiments, 1 mL paint thinner was volatilized in a glass chamber, where Plagiomnium cuspidatum and Myuroclada maximowiczii were used. As a result, it was found that particulate matter was effectively removed by the three mosses, and the removal efficiency of particulate matter increased as the amount of mosses increased. The amount of VOCs was similar to the level in the control when a low amount of mosses (2 and 4 plates) was used. However, the removal efficiency of VOCs was significant when 6 plates of mosses were used. On the other hand, formaldehyde concentration was 40 times more than the control and carbon monoxide 30 times, when 0.2 g of mosquito repellent was completely burned in a glass chamber. Also formaldehyde removal effect was significant when 6 plates of mosses were placed. However, there was no change in the concentration of indoor oxygen, temperature and humidity by moss plants. In conclusion, the moss plants were effective in removing particulate matter and VOCs, and they are expected to be used for indoor decoration and landscape in order to improve indoor air quality in the future.