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Evaluation of Chloride and Chemical Resistance of High Performance Mortar Mixed with Mineral Admixture (광물성 혼화재료를 혼입한 고성능 모르타르의 염해 및 화학저항성 평가)

  • Lee, Kyeo-Re;Han, Seung-Yeon;Choi, Sung-Yong;Yun, Kyong-Ku
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.5
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    • pp.618-625
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    • 2018
  • With the passing of time, exposed concrete structures are affected by a range of environmental, chemical, and physical factors. These factors seep into the concrete and have a deleterious influence compared to the initial performance. The importance of identifying and preventing further performance degradation due to the occurrence of deterioration has been greatly emphasized. In recent years, evaluations of the target life have attracted increasing interest. During the freezing-melting effect, a part of the concrete undergoes swelling and shrinking repeatedly. At these times, chloride ions present in seawater penetrate into the concrete, and accelerate the deterioration due to the corrosion of reinforced bars in the concrete structures. For that reason, concrete structures located onshore with a freezing-melting effect are more prone to this type of deterioration than inland structures. The aim of this study was to develop a high performance mortar mixed with a mineral admixture for the durability properties of concrete structures near sea water. In addition, experimental studies were carried out on the strength and durability of mortar. The mixing ratio of the silica fume and meta kaolin was 3, 7 and 10 %, respectively. Furthermore, the ultra-fine fly ash was mixed at 5, 10, 15, and 20%. The mortar specimens prepared by mixing the admixtures were subjected to a static strength test on the 1st and 28th days of age and degradation acceleration tests, such as the chloride ion penetration resistance test, sulfuric acid resistance test, and salt resistant test, were carried out at 28 days of age. The chloride diffusion coefficient was calculated from a series of rapid chloride penetration tests, and used to estimate the life time against corrosion due to chloride ion penetration according to the KCI, ACI, and FIB codes. The life time of mortar with 10% meta kaolin was the longest with a service life of approximately 470 years according to the KCI code.

Effect of Dietary Fish Oil on Lipid Peroxidation in Rats Liver and Brain During Postnatal Development (어유섭취가 출생후 발달과정의 흰 쥐의 간과 뇌조직의 지질과산화와 그 관련기능에 미치는 영향)

  • 박명희
    • Journal of Nutrition and Health
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    • v.20 no.2
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    • pp.111-121
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    • 1987
  • Lipie peroxide formation, antiperoxidative s system and body adaptability for handling lipid p peroxide were examined in the first and second g generations of rats fed fish oil. Mackerel oil(MO) was used and four other dietary oils and fat, i.e. soybean oil(SO), perilla oil(PO), rapeseed oil(RO) and beef tallow(BT) were also employed to compare the effect of fish oil. Synthetic diets containing these five dietary fats at the level of 1O%(w/w), were given to the correspond­m ing groups of male and female rats weighing about 70 grams. After 34 days of feeding, male a and female rats were mated and their offsprings were raised throughout suckling (17, 26 days) and weanling (39 days) periods. Liver lipid pero­x xide level was highest in MO group of both first (mother rats after lactation) and second genera­t tions of 17 and 26 days old, but not of 39 days old. During suckling period, liver lipid peroxide level was well matched to total unsaturation of dietary fat. Brain lipid peroxide levels were not different among five groups. Liver $alpha$-tocopherol a and reduced glutathione (GSH) levels were lowest in MO fed first generation. In second generation, $alpha$-tocopherol level was also low in MO group, although the effect was less pronoun­c ced, but GSH level was not different from other groups. Oxidized glutathione (GSSG) level did not consistently vary by change in dietary fat. Glutathione peroxidase activity increased as young rats grew up to 39 days. Superoxide d dismutase activity change was insignificant by a age, but was shown as lowest in MO group. At the age of 26 and 39 days, liver glutatione peroxidase activity was increased as was level of lipid peroxide, suggesting that this is the one of the mechanisms responsible for body adapta­b bility for protection against the accumulation of lipid peroxide.

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Studies on the Quantitative Changes of Riboflavin during Takju Brewing (탁주양조중 Riboflavin의 소장에 관한 연구)

  • Kim, Chan-Jo;Choi, Woo-Young
    • Applied Biological Chemistry
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    • v.13 no.3
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    • pp.219-222
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    • 1970
  • Riboflavin in the various materials which used for Takju brewing was determined and its quantitative changes in the Takju mashes which were mashed with polished rice and wheat flour respectively using Nuruk only for enzyme source, and with wheat flour and corn powder respectively using Nuruk and Koji, were checked at 24 hours intervals during the whole brewing period. The results obtained were as follows. a) The riboflavin contents in 100 grams of each materials were: Polished rice $46.9{\gamma}$ Wheat flour $67.3{\gamma}$ Corn powder $73.9{\gamma}$ Nuruk $169.0{\gamma}$ Koji of wheat flour $87.1{\gamma}$ Koji of corn powder $84.4{\gamma}$ b) About 30 to 40 percent of riboflavin in the polished rice, wheat flour and corn powder were losed by steaming at 10 pounds for 50 minutes. c) Riboflavin content in the plots used Nuruk only was decreased during 3 days after mashing and then increased markedly after 5 days and, more or less, decreased after 6 days. Quantitative changes of riboflavin in the plots used Nuruk and Koji showed a rugged curve without decreasing in early stages, and its content was also increased markedly 5 days after mashing and then decreased a little after 6 days. d) Approximately $82{\gamma}$ of riboflavin was determined in 100ml. of the ripened mash of the rice plot and $72{\gamma}$ in the wheat flour plot in the case of using Nuruk only. $88.6{\gamma}$ of riboflavin were determined in 100ml. of the ripened mash of the wheat flour plot and $83.6{\gamma}$ in the corn powder plot in the case of using Nuruk and Koji. e) It was assumed that $28.8{\gamma}$ to $41{\gamma}$ of riboflavin were contained in 100 ml. of finished Takju of the two plots used Nuruk only and 33.6 to 44.5${\gamma}$ in the both two plots used Nuruk and Koji. f) About $47.3{\gamma}$ of riboflavin were determined in 100 grams of Takju cake of the rice plot and $66.2{\gamma}$ in the wheat flour plot used Nuruk only, and $62.9{\gamma}$ in the corn powder plot and $64.5{\gamma}$ in the wheat flour plot used Nuruk and Koji.

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Studies on the Yeasts for the Brewing of Soy Sauce(2) -Isolation, identification and classification of the yeasts in the soy sauce mash- (간장발효에 관여하는 효모에 관한 연구 (제2보) -간장 덧 중에 생육하는 효모에 대하여-)

  • Lee, Taik-Soo;Lee, Suk-Kun;Shin, Bo-Kyu
    • Applied Biological Chemistry
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    • v.13 no.2
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    • pp.171-180
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    • 1970
  • The yeasts in the soy sauce mash were isolated and identified, and they were classified by coloring with the treatment of TTC(2, 3, 5, triphenyltetrazolium chloride) agar and counted in process of time. The results obtained were as follows: a) The number of ordinary and osmophilic yeasts in 1 ml. of the soy sauce mash showed a tendency to be increased from the mashing to the mature stages and to decrease in the aging stages: $127{\times}10^3$ immediately after mashing, $83{\times}10^3$ 1 month after, $356{\times}10^3$ 3 months after, $1250{\times}10^3$ 6 months after and $65{\times}10^3$ 2 years after mashing in the case of ordinary yeasts, and 0 after mashing, $40{\times}10^3$ 1 month after, $81{\times}10^3$ 3 months after, $358{\times}10^3$ 6 month after and $23{\times}10^3$ 2 years after mashing in the case of osmophilic yeasts. b) 50 strains of yeasts were isolated from the soy sauce mash optionally in process of fermentation period, and they were identified as 7 genera and 18 species: 10 strains of Saccharomyces rouxii, 1 strain of Saccharomyces marxianus, 3 strains of Saccharomyces rosei, 1 strain of Saccharomyces fermentati, 6 strains of Saccharomyces mellis, 1 strain of Saccharomyces acidifaciens, 1 strain of Saccharomyces pastori, 3 strains of Pichia polymorpha, 2 strains of Hansenula anomala, 1 strain of Hansenula saturnus, 2 strains of Hansenula suaveolens, 5 strains of Nadsonia fulvescens, 8 strains of Debaryomyces hasenii, 1 strain of Debaryomyces nicotianae, 1 strain of Debaryomyces kloeckeri, 2 strains of Torulopsis sake, 1 strain of Torulopsis holmii and 1 strain of Candida pelliculasa. c) Distribution of yeasts according to the fermentation period was as follows: i) Saccharomyces rouxii, Saccharomyces marxianus, Saccharoymces rosei, Pichia polymorpha, Debaryomyces hansenii, Torulopsis sake, Candida pelliculosa, Debaryomyces nicotianae, Nadsonia fulvescens, Hansenula suaveolens and Hansenula saturnus were found in the early stages of fermentation. ii) Saccharomyces rouxii, Saccharomyces rosei, Saccharomyces fermentati, Saccharomyces mellis, Saccharomyces pastori, Hansenula anomala, Saccharomyces acidifaciens and Debaryomyces hansenii appeared in the mature stages. iii) Saccharomyces rouxii, Saccharomyces mellis, Nadsonia fulvescenes, Dedaryomyces hansenii, Debaryomyces kloeckeri, Torulopsis sake and Torulopsis holmii were distributed in the aging stages. d) TTC white yeasts were found in abundance in the early stages of fermentation and TTC red yeasts appeared more than 50 per cent in the mature and aging stages. e) The yeasts belonging to Saccharomyces mellis and Saccharomyces pastori were classified as TTC red yeasts, Saccharomyces acidifaciens were reel pink, Hansenula saturnus Debaryomyces kloeckeri, and Torulopsis holmii were pink, Saccharomyces marxianus and Nadsonia fulvescens were white and the others were the same as the description in the previous report. Saccharomyces rouxii ware classified for the most part as TTC red yeasts, and while some of them were red pink. f) Species of yeasts in the soy sauce mash were similar to those in the soy sauce koji, but the latter were not osmophilic and in the former case, the osmophilic yeasts were increased in process of fermentation period.

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A Study on the Manufacturing of Soysauce by the Use of Milled Barely (보리를 이용(利用)한 간장제조(製造)에 관한 연구(硏究))

  • Kim, Hyung-Soo;Kim, Ze-Uook
    • Applied Biological Chemistry
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    • v.29 no.2
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    • pp.107-115
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    • 1986
  • The chemical changes and the quality of the soysauce which was Bade by new convenient method using vinyl teat instead of koji room, replacing wheat with milled barley koji were investigated. Protease activity of the koji was higher as tile ratio of soybeans was increased but amylase activity was higher as the ratio of milled barley was increased. The amounts of total nitrogen showed substantial increases until 80 days and afterwards, their rates of increases were lower. The more its content of soybeans, the higher its amount of total nitrogen, The amount of amino nitrogen increased slowly in all samples and the sample which had a large amount of soybeans was higher than those with small amounts of soybeans. The amount of ammonia nitrogen showed increases until 120 days tut decreased after then. The amount of reducing sugar showed increases until 80 days and decreased after then and the greater its source of carton, the higher its amount of reducing sugar. The total acid contort had large increases until 100 days in all samples and afterward they did not show any particular changes. The changes of pH decreased for 100 days and afterwards, they increased a little. In the original soysauce, combined ratio of soybean 3 to milled barley 2 and the sample of those ratio 4 : 1 are better than others and in diluted soysauce combined ratio of soybean 4 to milled barley 1 is better than the others. In original soysauce the use of $20{\sim}40%$ barley koji, which is added to soybeans, is superior and diluted soysauce the use of 20% barley koji is superior.

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Assessment of Chromosomal Analyses of 1,180 Cases Suspected of Chromosomal Aberrations (염색체이상을 의심한 1,180례의 염색체 분석 결과 검토)

  • Jeong, Hyeon Kyoung;Ahn, Eun Young;Rim, Sung Soo;Kim, Eun Young;Kim, Kyoung Sim;Kim, Yong Wook;Kim, Ki Bok
    • Clinical and Experimental Pediatrics
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    • v.45 no.3
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    • pp.311-319
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    • 2002
  • Purpose : We have performed this study to obtain reference data for the distribution of chromosomal aberrations in Korea. Methods : We analyzed 1,180 chromosomal study cases from Kwang ju Christian Hospital during the past 25 years. 756 cases suspected of characteristic chromosomal aberration syndromes and 424 cases with hermaphroditism, mild sexual abnormalities, multiple anomalies, or mental & growth retardation were included. Results : The male to female ratio of autosomal aberration syndromes was 1.2 : 1. 78.6% of autosomal aberrations were diagnosed under 1 year of age, whereas 89.8% of sex chromosomal aberrations were diagnosed over 12 years of age. Among 1,180 cases, 612 ones had chromosomal aberrations(51.9%) : 590 of 756 cases suspected of chromosomal aberration syndromes had aberrations( 78.0%), whereas 22 of 424 showing the above other features had aberrations(5.2%). Autosomal aberrations appeared in 514 cases(83.8%) and sex chromosomal aberrations appeared in 98 cases(16.2%). The most frequently observed abberation in autosomal aberrations was Down syndrome, followed by E, D, B, A and C group aberrations. The most common abberation in sex chromosomal aberrations was Turner syndrome, followed by Klinefelter syndrome and Fragile X syndrome. Conclusion : It is of vital importance that patients suspected of chromosomal aberrations undergo chromosomal analysis. Further advanced chromosomal staining and molecular genetic methods will raise the detection rate of chromosomal aberrations.

Metabolic syndrome in the overweight and obese adolescents and the impact of obesity on the cardiovascular system (과체중과 비만 청소년에서 대사증후군과 비만이 심혈관에 미치는 영향)

  • Hong, Young Mi;Song, Young Whan;Kim, Hae Soon;Park, Hae Sook;Min, Jung Hae;Jung, Jo Won;Kim, Nam Su;Noh, Chung Il
    • Clinical and Experimental Pediatrics
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    • v.52 no.10
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    • pp.1109-1118
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    • 2009
  • Purpose : Metabolic syndrome (MS), characterized by obesity and insulin resistance, elicits risk factors such as hyperlipidemia, hypertension, and glucose intolerance with additive effects on atherosclerosis, leading to cardiovascular diseases. The purposes of this study were to evaluate the prevalence of MS among overweight and obese adolescents and to investigate the impact of obesity on the cardiovascular system. Methods : In all, 684 adolescents were included in the study. Blood pressure, body mass index (BMI), fasting blood glucose, total cholesterol, triglyceride, low-density-lipoprotein (LDL)-cholesterol, high-density-lipoprotein (HDL)-cholesterol, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and high-sensitive C-reactive protein (hs-CRP) were measured in the patients with a BMI of >85 percentile. Brachial-ankle pulse wave velocity (BaPWV) and ankle brachial index were measured using Vascular Profiler (VP)-1000. Results : MS was confirmed in 19.5% of the overweight and obese adolescents and 50.8% of the obese adolescents. The systolic and diastolic blood pressure, height, weight, fat mass, %fat, BMI, obesity index, and waist circumference were higher in the overweight and obese adolescents with MS. Moreover, the triglyceride, AST, ALT, and hs-CRP levels were higher, whereas HDL-cholesterol level was significantly lower in this group. The overweight and obese adolescents with MS showed shorter diastolic and systolic times, higher heart rate and BaPWV, and longer E-wave deceleration time by echocardiography. Conclusion : Overweight and obese adolescents showed characteristic MS features such as hypertension and hyperlipidemia. Thus, obese adolescents predisposed to MS should be provided early treatment for obesity.

A Morphologic Study of Head and Face of Man in the Age 30 to 40 according to Sasang Constitution (30-40대(代) 남성(男性)의 사상체질별(四象體質別) 안면특징(顔面特徵)에 관(關)한 연구(硏究))

  • Jung, Kwang-Hee;Koh, Byung-Hee;Song, Il-Byung
    • Korean Journal of Oriental Medicine
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    • v.6 no.1
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    • pp.29-46
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    • 2000
  • The clinical application of constitutional Diagnosis is the most important part of Sasang constitutional medicine. It has been studied in various way. The study of morphologic characteristics on the head and face has been identified but didn't considered the Variations of age and sex. For the statistic analysis of the correlation between the sasang constitution and the shape of the face, the head-facial part of 182 cases(the group of throughout the age) and 69 cases(the group of age 30 to 40) were measured by Martin's measurement and analysis of a) the measurement value of height and the component ratio from the Gnathion to each part of face by constitution. b) the measurement value of depth and the component ratio from T-projected to each part of the face by constitution. c) the measurement value of breadth and component ratio between each parts of the facial breadth by constitution. d) the characteristics on each part of face by constitution. e) the result of discriminant analysis about the constitution Authors obtained the results from the study as follows: 1. Taeum-In group is characterized by the value of variables had a tendency to maximum value in throughout the age, the charateristics that the total group show is the shape of face is wide shape in horizontally and flat, the nasal breadth is wider than other constitutions, the lips is narrower than Soyang-In in horizontally and thick shape in vertically, and the biogonial breadth is more developed than other constitutions, so lower face is developed. The charateristics that only the age of 30 40 group show is that the lips is thicker than Soeum-IN. The projection of inter-eyebrows is more projected than Soyang-IN. 2. Soeum-IN group is characterized by the value of variables had a tendency to minimum value in throughout the age. The characteristics that the total group show is the lips is thiner than other constitutions, the breadth of eyes is wider than other constitutions, the difference between sellion and nasal breadth is to be little. The charateristics that only the age of 30 40 group show is that the ratio of upper face in physiognomic face is lager than Soyang-IN. 3. The total age group of Soyang-In is characterized by the shape of face is long in vertically and narrow in horizontally, the total eyebrow breadth and lips and philtrun is wider than other constitutions. The charateristics that only the age of 30 40 group is characterized by the projection of sellion is more projected than Taeum-IN. 4. The values which showed significance in both age group V76, V52, V54, V55, V57, V59, V64, V65, V67, V88, V89, V148, V150, V151, V155, V160, V161, V28, V50, V99, V102, V167, V169, V173, V175, V177, V181 are 27 in all. 5. The values which was significant in the age 30 to 40 group V77, V78, V79, V109, V140, V142, V143, V166, V174 are 9 in all.

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Structural Behavior of Mixed $LiMn_2O_4-LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ Cathode in Li-ion Cells during Electrochemical Cycling

  • Yun, Won-Seop;Lee, Sang-U
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.05a
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    • pp.5-5
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    • 2011
  • The research and development of hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and electric vehicle (EV) are intensified due to the energy crisis and environmental concerns. In order to meet the challenging requirements of powering HEV, PHEV and EV, the current lithium battery technology needs to be significantly improved in terms of the cost, safety, power and energy density, as well as the calendar and cycle life. One new technology being developed is the utilization of composite cathode by mixing two different types of insertion compounds [e.g., spinel $LiMn_2O_4$ and layered $LiMO_2$ (M=Ni, Co, and Mn)]. Recently, some studies on mixing two different types of cathode materials to make a composite cathode have been reported, which were aimed at reducing cost and improving self-discharge. Numata et al. reported that when stored in a sealed can together with electrolyte at $80^{\circ}C$ for 10 days, the concentrations of both HF and $Mn^{2+}$ were lower in the can containing $LiMn_2O_4$ blended with $LiNi_{0.8}Co_{0.2}O_2$ than that containing $LiMn_2O_4$ only. That reports clearly showed that this blending technique can prevent the decline in capacity caused by cycling or storage at elevated temperatures. However, not much work has been reported on the charge-discharge characteristics and related structural phase transitions for these composite cathodes. In this presentation, we will report our in situ x-ray diffraction studies on this mixed composite cathode material during charge-discharge cycling. The mixed cathodes were incorporated into in situ XRD cells with a Li foil anode, a Celgard separator, and a 1M $LiPF_6$ electrolyte in a 1 : 1 EC : DMC solvent (LP 30 from EM Industries, Inc.). For in situ XRD cell, Mylar windows were used as has been described in detail elsewhere. All of these in situ XRD spectra were collected on beam line X18A at National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory using two different detectors. One is a conventional scintillation detector with data collection at 0.02 degree in two theta angle for each step. The other is a wide angle position sensitive detector (PSD). The wavelengths used were 1.1950 ${\AA}$ for the scintillation detector and 0.9999 A for the PSD. The newly installed PSD at beam line X18A of NSLS can collect XRD patterns as short as a few minutes covering $90^{\circ}$ of two theta angles simultaneously with good signal to noise ratio. It significantly reduced the data collection time for each scan, giving us a great advantage in studying the phase transition in real time. The two theta angles of all the XRD spectra presented in this paper have been recalculated and converted to corresponding angles for ${\lambda}=1.54\;{\AA}$, which is the wavelength of conventional x-ray tube source with Cu-$k{\alpha}$ radiation, for easy comparison with data in other literatures. The structural changes of the composite cathode made by mixing spinel $LiMn_2O_4$ and layered $Li-Ni_{1/3}Co_{1/3}Mn_{1/3}O_2$ in 1 : 1 wt% in both Li-half and Li-ion cells during charge/discharge are studied by in situ XRD. During the first charge up to ~5.2 V vs. $Li/Li^+$, the in situ XRD spectra for the composite cathode in the Li-half cell track the structural changes of each component. At the early stage of charge, the lithium extraction takes place in the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component only. When the cell voltage reaches at ~4.0 V vs. $Li/Li^+$, lithium extraction from the spinel $LiMn_2O_4$ component starts and becomes the major contributor for the cell capacity due to the higher rate capability of $LiMn_2O_4$. When the voltage passed 4.3 V, the major structural changes are from the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, while the $LiMn_2O_4$ component is almost unchanged. In the Li-ion cell using a MCMB anode and a composite cathode cycled between 2.5 V and 4.2 V, the structural changes are dominated by the spinel $LiMn_2O_4$ component, with much less changes in the layered $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, comparing with the Li-half cell results. These results give us valuable information about the structural changes relating to the contributions of each individual component to the cell capacity at certain charge/discharge state, which are helpful in designing and optimizing the composite cathode using spinel- and layered-type materials for Li-ion battery research. More detailed discussion will be presented at the meeting.

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Weed flora of agricultural area in Korea (우라나라 농경지(農耕地)의 주요(主要) 잡초분포(雜草分布) 현황(現況))

  • Kim, S.C.;Oh, Y.J.;Kwon, Y.W.
    • Korean Journal of Weed Science
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    • v.12 no.4
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    • pp.317-334
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    • 1992
  • Weed flora and floristic composition were reviewed in lowland rice field and upland crop area. For lowland rice field weed flora was not much changed since 1971. About 29 weed species belonged to 18 families were occurred. However, floristic composition of dominant weed species has greatly changed mainly due to introduction of herbicides. The predominant weed species in 1971 when herbicide was not used were Rotala indica, Eleocharis acicularis, Monochoria vaginalis, Echinochloa crus-galli, while these for in 1991 were Eleocharis kuroguwai, Sagittaria pygmaea, S. trifolia, Echinochloa crus-galli and M, vaginalis, respectively. In 1981 weed survey, E. crus-galli was no longer troblesome weed. However, this species became important again thereafter by introduction of herbicide mixtures with pyrazolate, bensulfuron-methyl or pyrazosulfuronethyl. For upland crop area, 216 weed species belonged to 46 families were recorded. One hundred and sixtyfive of these were grown in winter crop area while 189 weed species occurred in summer crop area, respectively. Among these, 138 weed species were grown in both crop seasons. In general, summer crops had less number of weed species compared to winter crops. Even though the dominant weed species varied by crop the most common weeds were Chenopodium album, Alopecunrs aqualis, Stellaria alsine and S, media for winter crops and Digitaria sanguinalis, Portulaca oleracea, Chenopodium album and Acalypha australis for summer crops, respectively.

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