• Title/Summary/Keyword: Chemical density

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Biological Activity of Organic Solvent Fractions from Lythrum salicaria L. (Root) (털부처꽃 뿌리로부터 조제된 분획물의 생리활성)

  • Lee, Seung-Eun;Kim, Geum-Soog;Han, Hee-Sun;Lee, Eun-Suk;Kim, Young-Ok;Lee, Jeong-Hoon;Seong, Nak-Sul;Lee, Sang-Won;Kim, Young-Chul
    • Korean Journal of Medicinal Crop Science
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    • v.18 no.5
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    • pp.323-328
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    • 2010
  • Root extract of Lythrum salicaria reported a hepato-protective effect on $CCl_4$-induced liver toxicity of rat was prepared into fractions such as n-hexane up layer (HA), n-hexane down layer (HB), diethyl ether (E), ethylacetate (EA), n-butanol (B) and water (W). Fractions prepared were tested their activities in vitro and in vivo condition. All of the fractions showed effective antioxidant asctivities on DPPH radical and $CuSO_4$-induced oxidation of human low density lipoprotein and E fraction showed the highest inhibitory effect (98.1% at $50\;{\mu}g/m{\ell}$) on linoleic acid autoxidation at $40^{\circ}C$, which was more effective than $\alpha$-tocopherol (82.4%). Five fractions (H = HA plus HB, E, EA, B, and W, 150 mg/kg/day) were fed into Sprague Dawley, male rats for 4 days, which were intoxicated with intra-peritoneal injection of carbon tetrachloride ($1\;m{\ell}/kg$ in corn oil) at the 4th day and were sacrificed in 24 hrs. Serum tumor necrosis factor-alpha (TNF-$\alpha$), a proinflammatory cytokine, elevated with $CCl_4$-intoxication in negative control group ($83\;pg/m{\ell}$) was significantly decreased in E fraction-supplemented group ($18\;pg/m{\ell}$). Cu, Zn-superoxide dismutase (SOD) activity increased in negative control group (0.12 U/mg protein) was decreased in E fraction (0.07 U/mg protein). From the results, it is suggested that ether fraction from root extract of L. salicaria would be a potent antioxidant candidate for ameliorating liver injury induced by chemical intoxicant.

Effect of Lugol's Iodine Preservation on Cyanobacterial Biovolume and Estimate of Live Cell Biovolume Using Shrinkage Ratio (Lugol's Iodine Solution 첨가 후 보존 기간별 남조류 세포부피 변화 및 수축비를 이용한 생세포 부피 산정)

  • Park, Hae-Kyung;Lee, Hyeon-Je;Lee, Hae-Jin;Shin, Ra-Young
    • Journal of Korean Society on Water Environment
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    • v.34 no.4
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    • pp.375-381
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    • 2018
  • The monitoring of phytoplankton biomass and community structure is essential as a first step to control the harmful cyanobacterial blooms in freshwater systems, such as seen in rivers and lakes, due to the process of eutrophication and climate change. In order to quantify the biomass of phytoplankton with a wide range in size and shape, the measurement of cell biovolume along with cell density is required for a comprehensive review on this issue. However, most routine monitoring programs preserve the gathered phytoplankton samples before analysis using chemical additives, because of the constraint of time and the number of samples. The purpose of this study was to investigate the cell biovolume change characteristics of six cyanobacterial species, which are common bloom-causing cyanobacteria in the Nakdong River, after the preservation with Lugol's iodine solution. All species showed a statistically significant difference after the addition of Lugol's iodine solution compared to the live cell biovolume, and the cell biovolume decreased to the level of 34.0 ~ 56.3 % at maximum in each species after the preservation. The nonlinear regression models for determining the shrinkage ratio by a preservation period were derived by using the cell biovolume measured until 180 days preservation of each target species, and the equation to convert the cell biovolume measured after preservation for a certain period to the cell biovolume of viable cell was derived using that formula. The conversion equation derived from this study can be used to estimate the actual cell biovolume in the natural environment at the time of sampling, by using the measured biovolume after the preservation in the phytoplankton monitoring. Moreover this is expected to contribute to the final interpretation of the water quality and aquatic ecosystem impacts due to the cyanobacterial blooms.

The Effect of the Deposition Temperature and la Doping Concentration on the Properties of the (Pb, La)$\textrm{TiO}_3$ Films Deposited by ECR PECVD (증착온도와 La조성비가 ECR 플라즈마 화학기상증착법으로 증착한 (Pb, La)$\textrm{TiO}_3$박막의 물성에 미치는 영향)

  • Jeong, Seong-Ung;Park, Hye-Ryeon;Lee, Won-Jong
    • Korean Journal of Materials Research
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    • v.7 no.3
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    • pp.196-202
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    • 1997
  • Perovskite lanthanum doped lead titanate ($(Pb,La)TiO_{3}$ or PLT) thin films were successfully fabricated on Pt/TijSiO.iSi substrates at the temperatures as low as $440~500^{\circ}C$ by eleclron cyclotron resonance plasma-enhanced chemical vapor deposition (ECR PECVII). Since the volatilities of the MC sources arid oxide molecules (especially Ph oxide) increased with increasing deposition temperature, the film deposition rate and the (I'b + La)/'Ti ratio decreased Stoichiometric perovskite PL'T films with good dielectric and leakeage current properties were obtained at the temperatures of $460~480^{\circ}C$. The lanthanum content of the film was nearly directly propotional to $La(DPM)_{3}$ flow rate. As the La/Ti ratio increased from 3.0 to 9.5%, the dielectric constant increased from 360 to 650 and the leakeage current density at 100kV/cm electric field decreased from $4{\times}10^{-5}$ to $4{\times}10_{-8}A/cm^2$.

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T$a_2O_5$Dielectric Thin Films by Thermal Oxidation and PECVD (열산화법 및 PECVD 법에 의한 T$a_2O_5$ 유전 박막)

  • Mun, Hwan-Seong;Lee, Jae-Seok;Lee, Jae-Seok;Lee, Jae-Seok;Yang, Seung-Gi;Lee, Jae-hak;Park, Hyung-ho;Park, Jong-wan
    • Korean Journal of Materials Research
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    • v.2 no.5
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    • pp.353-359
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    • 1992
  • Thermal oxidation and plasma enhanced chemical vapor deposition of tantalum oxide thin films on p-type (100) Si substrates were studied to examine the dielectric nature of T$a_2O_5$ as a Al/T$a_2O_5$/p-Si capacitor. Microstructure and dielectric properties of the capacitors were investigated by XRD, AES, high frequency C-V analyzer, I-V meter and TEM. XRD analysis showed that the structure of T$a_2O_5$ films were amorphous, but the films were crystallized to hexagonal $\delta$-T$a_2O_5$ by 65$0^{\circ}C$ thermal oxidation treatment. It was found that the stoichiometry of the films was more or less close to 2 : 5. Leakage current density and relative dielectric constant of thermal oxidation T$a_2O_5$ film at 60$0^{\circ}C$ was 5.0${ imes}10^{-6}$/A/c$m^2 and 31.5, respectively. In the case of PECVD T$a_2O_5$film deposited at 0.47W/c$m^2 they were 2.5${ imes}10^{-5}$/A/$ extrm{cm}^2$ and 24.0, respectively. The morphology of the films and interfaces were investigated by TEM.

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Control Effect of Insecticides against Chilo suppressalis Walker of Native Miscanthus in Korea (국내 자생 억새를 가해하는 이화명나방의 방제 처리 효과)

  • Yu, Gyeong-Dan;Lee, Ji-Eun;Jang, Yun-Hui;Moon, Youn-Ho;Cha, Young-Lok;Song, Yeon-Sang;Lee, Kyeong-Bo
    • Weed & Turfgrass Science
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    • v.5 no.4
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    • pp.230-235
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    • 2016
  • Miscanthus are perennial rhizomatous grasses and considered as an ideal cellulosic bioenergy crop. Recently, it was reported that Miscanthus was damaged by the larvae of rice stem borer, Chilo suppressalis Walker, one of the most destructive pests of rice in Korea since the 1960s. This study was thus conducted to evaluate the insecticidal effects against rice stem borer in the Miscanthus cultivation fields for two years. The experiment consisted of four chemical agent plots, one environment-friendly agent plot, and untreated plot. Untreated plot showed significantly high damage of 50%, while Buprofezin Tebufenozide and Carbosulfan Methoxyfenozide treatment plots showed low damage rate of 2% with low larvae density of 1 and $2.3larvae\;m^{-2}$, respectively. Damage rates of Tebufenozide, ChlorantraniliproleIndoxacarb, and environment-friendly agent(MatrineWood vinegar solution) were 15, 26, and 18%, respectively, which were lower than that of untreated plot but higher than those of Buprofezin Tebufenozide and Carbosulfan Methoxyfenozide. In conclusion, rice insecticides were effective against rice stem borer in Miscanthus field. In particular, the treatments with Buprofezin Tebufenozide and Carbosulfan Methoxyfenozide showed excellent control effects with control value of 93.3 and 95.2. However, further studies with different types of insecticides should be carried out for the selection of insecticides with more effective control of rice stem borer.

Quality Characteristics of Cookies Prepared with Varied levels of Shredded Garlics (다양한 수준의 마늘 첨가 쿠키의 품질 특성 연구)

  • L.Kim, Hye-Young;Jeong, Su-Jin;Heo, Mi-Yeon;Kim, Kang-Sung
    • Korean Journal of Food Science and Technology
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    • v.34 no.4
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    • pp.637-641
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    • 2002
  • The purpose of this study was to provide the basic information on the cookies made with garlic and to investigate quality characteristics of them using chemical and sensory evaluation of cookies. Cookie samples were prepared with shredded garlic at varied levels of 0, 3, 6 and 9%. The pH of the dough significantly decreased by the addition of garlic. Dough density of control showed significantly lower values than those of 3% added sample groups. Spreadability of control had significantly higher values than the other samples. Texture measurement showed that the addition of garlic had no significant effect on cookie texture. Sensory evaluation resulted that the properties of crack, garlic aroma, garlic taste and brittleness of cookies tended to increase as the addition levels of garlic were increased. The cookies with 3% and 6% garlic had similar or significantly higher acceptance scores in all of the properties examined than those of control.

Quality Characteristics of Cookies added with Asparagus Powder (아스파라거스 분말을 첨가한 쿠키의 품질 특성)

  • Yang, Seung-Mi;Kim, Sung-Hyun;Shin, Jung-Hye;Kang, Min-Jung;Sung, Nak-Ju
    • Journal of agriculture & life science
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    • v.44 no.2
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    • pp.67-74
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    • 2010
  • The characteristics of cookies added asparagus (Asparagus officinals L.) powder were analyzed by chemical and sensory evaluation. Samples were prepared with different levels (0, 0.5, 1, 2, 3 and 5%) of freeze-dried asparagus powder. The lowest pH of the cookie dough was pH 6.26 in the 5% asparagus powder added group. Density value of cookie dough was decreased by increase of asparagus powder addition volume. Spread factor and hardness of cookie was significantly increased by addition of asparagus powder. And hardness was the highest in 5% asparagus powder added cookie, however there was no remarkable different between 0.5~1% added group and control. Hunter color L and a-value of dough was decreased significantly, while b-value was increased when concentration of asparagus powder was added greater than 3%. L-value of cookie was significantly decreased with larger of asparagus powder addition volume and the lowest in the 5% asparagus powder added group (55.38). Hunter a-value of cookie showed not significantly differences in all groups. The sensory evaluation was not observed significantly differences by terms of color (3.77~4.77), brittleness (4.11~4.88), flavor (3.88~4.55), taste (4.11~5.00) and overall acceptability (4.00~4.77). From these results, we suggest that asparagus powder addition is possible up to 5% and is good ingredient for increasing the acceptability and functionality of cookies.

Influence of Gd0.1Ce0.9O2-δ Interlayer between La0.6Sr0.4Co0.2Fe0.8O3-δ Cathode and Sc-doped Zirconia Electrolyte on the Electrochemical Performance of Solid Oxide Fuel Cells (La0.6Sr0.4Co0.2Fe0.8O3-δ 공기극과 Sc이 도핑된 지르코니아 전해질 사이에 삽입한 Gd0.1Ce0.9O2-δ 중간층이 고체산화물 연료전지의 전기화학적 성능에 미치는 영향)

  • Lim, Jinhyuk;Jung, Hwa Young;Jung, Hun-Gi;Ji, Ho-Il;Lee, Jong-Ho
    • Ceramist
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    • v.21 no.4
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    • pp.378-387
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    • 2018
  • The optimal fabrication conditions for $Gd_{0.1}Ce_{0.9}O_{2-{\delta}}$(GDC) buffer layer and $La_{0.6}Sr_{0.4}Co_{0.2}Fe_{0.8}O_{3-{\delta}}$ (LSCF) cathode on 1mol% $CeO_2-10mol%\;Sc_2O_3$ stabilized $ZrO_2$ (CeScSZ) electrolyte were investigated for application of IT-SOFCs. GDC buffer layer was used in order to prevent undesired chemical reactions between LSCF and CeScSZ. These experiments were carried out with $5{\times}5cm^2$ anode supported unit cells to investigate the tendencies of electrochemical performance, Microstructure development and interface reaction between LSCF/GDC/CeScSZ along with the variations of GDC buffer layer thickness, sintering temperatures of GDC and LSCF were checked, respectively. Electrochemical performance was analyzed by DC current-voltage measurement and AC impedance spectroscopy. Microstructure and interface reaction were investigated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Although the interfacial reaction between these materials could not be perfectly inhibited, We found that the cell, in which $6{\mu}m$ GDC interlayer sintered at $1200^{\circ}C$ and LSCF sintered at $1000^{\circ}C$ were applied, showed good interfacial adhesions and effective suppression of Sr, thereby resulting in fairly good performance with power density of $0.71W/cm^2$ at $800^{\circ}C$ and 0.7V.

Effects of Soil Conditioners Application on the Change of Soil Properties and Soybean Yield in a Sandy Loam Soil (사질(砂質)밭에서 토양개량제(土壤改良劑) 처리(處理)가 토양(土壤特性)과 대두수량(大豆收量)에 미치는 영향(影響))

  • Hur, Bong-Koo;Jo, In-Sang;Um, Ki-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.22 no.4
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    • pp.296-300
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    • 1989
  • This study was carried out to evaluate the effects of clay loam soil, zeolite, and high molecular organic compounds on the improvement of soil physico-chemical properties and soybean yield in a sandy loam soil. Soybean was cultivated from 1987 to 1988. CEC, moisture retention of soil were increased, but soil bulk density and hardness were decreased by soil conditioners. Clay loam soil addition enhanced the soybean yield by 5% at 10ton 10a plot, 7% at 20ton/10a plot. Also zeolite application increased the soybean yield by 6~10%. Effects of soil conditioner application of the 1rst year were greater than that of 2nd year. Some experiments were conducted in laboratory for the effect of soil conditioners on soil physical properties. The nutrient and water holding capacity were highest by K-SAM treatment, but the soil aggregates was most stable by AN-905SH and Primal treatments.

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Influence of Diagnostic Fertilization and Subsoil Breaking on Soil physico-chemical Properties in Direct Seeding of Rice on Flooded Paddy Surface (벼 담수표면 직파재배시 진단시비와 심토파쇄가 토양이화학성 및 벼 생육에 미치는 영향)

  • Yoo, Chul-Hyun;Ryu, Jin-Hee;Yang, Chang-Hyu;Kim, Taek-Kyum;Kang, Seung-Weon;Kim, Jae-Duk;Jung, Kwang-Yong
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.6
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    • pp.334-338
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    • 2006
  • This study was conducted to evaluate the effect of improvement of soil physical properties such as deep plowing, subsoil breaking and diagnostic fertilization on the yield of rice and nitrogen-use efficiency in direct seeding on flooded paddy surface of rice. The effects of deep plowing, subsoil breaking and diagnostic application of N, P, K fertilizers, Latex coated urea(LCU), compost, silicate were investigated. The soil physical properties, such as bulk density, hardness and porosity were improved and the content of organic matter and available $SiO_2$ were also increased by deep plowing and subsoil breaking. The amount of $NH_4-N$ in soil was highly increased by diagnostic fertilization and deep plowing at 5th leaf stage. The nitrogen-use efficiency was the highest at the diagnostic application of LCU 70% applied as basal dressing with subsoil breaking. The yield of rice increased by 8% under the diagnostic application of LCU 70% applied as basal dressing with subsoil breaking compared with the conventional application.