• 제목/요약/키워드: $W^1_2-bound$

검색결과 74건 처리시간 0.029초

은행(Ginkgo biloba L.) 종실 및 잎 추출물의 항산화 효과에 관하여 (Antioxidative Effectiveness of Extract of Nut and Leaf of Ginkgo biloba L.)

  • 배지오;이기동;김정숙;윤형식
    • Current Research on Agriculture and Life Sciences
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    • 제9권
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    • pp.61-69
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    • 1991
  • 탈지 은행 종실 및 잎에서 유리페놀산, 에스터형 및 불용성 페놀산을 추출하여 식용 옥수수유 기질에서 항산화 효과를 비교하고자 0.02%(w/w)의 BHA, BHT와 각 추출물 $1m{\ell}$(2% w/w)를 넣어 $45{\pm}1^{\circ}C$의 항온기에서 45일간 저장하면서 매 5일 간격으로 과산화물가, TBA가를 측정하여 다음과 같이 항산화 효과를 추정하였다. BHA, BHT와 은행 종실의 유리페놀산, 에스터형 및 활용성 페놀산, 잎의 유리페놀산, 에스터형 및 불용성 페놀산 추출물을 첨가한 시험구와 대조구의 45일 저장후 과산화물가는 각각 133, 52, 115, 190, 127, 95, 140, 121, 280meq/kg, oil이었다. 한편 같은 조건하에서 각 항산화성 물질의 TBA가는 0.153, 0.059, 0.175, 0.260, 0.187, 0.160, 0.1 74, 0.195 0.430이었다. G.C.로 분리 확인된 페놀산은 은행 종실 및 잎 공히 Vanillin, ${\rho}$-Hydroxybenzoic acid, Syringic acid, Gallic acid, Protocatechuic acid가 확인되었고 은행 종실에서는 trans-Cinnamic acid, Caffeic acid가, 잎에서는 Coumaric acid, Gentisic acid, Phloroglucinol, Pyrogallol이 각각 확인되었다. 이상의 결과를 종합해 볼 때 은행 종실 및 잎의 페놀산은 식용 옥수수유 기질에서 우수한 항산화 효과가 있는 것으로 사료된다.

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Enhanced electrocapacitive performance and high power density of polypyrrole/graphene oxide nanocomposites prepared at reduced temperature

  • Mudila, Harish;Joshi, Varsha;Rana, Sweta;Zaidi, Mohmd. Ghulam Haider;Alam, Sarfaraz
    • Carbon letters
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    • 제15권3호
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    • pp.171-179
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    • 2014
  • An attempt was made to investigate the effect of the preparation temperature on the electrocapacitive performance of polypyrrole (PPY)/graphene oxide (GO) nanocomposites (PNCs). For this purpose, a series of PNCs were prepared at various temperatures by the cetyltrimethylammonium bromide-assisted dilute-solution polymerization of pyrrole in presence of GO (wt%) ranging from 1.0 to 4.0 with ferric chloride as an oxidant. The formation of the PNCs was ascertained through Fourier-transform infrared spectrometry, X-ray diffraction spectra, scanning electron microscopy and simultaneous thermogravimetric-differential scanning calorimetry. The electrocapacitive performance of the electrodes derived from sulphonated polysulphone-bound PNCs was evaluated through cyclic voltammetry with reference to Ag/AgCl at a scan rate (V/s) ranging from 0.2 and 0.001 in potassium hydroxide (1.0 M). The incorporation of GO into the PPY matrix at a reduced temperature has a pronounced effect on the electrocapacitive performance of PNCs. Under identical scan rates (0.001 V/s), PNCs prepared at $10{\pm}1^{\circ}C$ render improved specific conductivity (526.33 F/g) and power density (731.19 W/Kg) values compared to those prepared at $30{\pm}1^{\circ}C$ (217.69 F/g, 279.43 W/Kg). PNCs prepared at $10{\pm}1^{\circ}C$ rendered a capacitive retention rate of ~96% during the first 500 cycles. This indicates the excellent cyclic stability of the PNCs prepared at reduced temperatures for supercapacitor applications.

Purification, crystallization and X-ray diffraction of heparan sulfate bounded human RAGE

  • Park, Jun bae;Yoo, Youngki;Ong, Belinda Xiang Yu;Kim, Juyeon;Cho, Hyun-Soo
    • Biodesign
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    • 제5권3호
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    • pp.122-125
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    • 2017
  • Receptor for advanced glycation end products (RAGE) is one of the single transmembrane domain containing receptors and causes various inflammatory diseases including diabetes and atherosclerosis. RAGE extracellular domain has three consecutive IgG-like domains (V-C1-C2 domain) which interact with various soluble ligands including heparan sulfate or HMGB1. Studies have shown that each ligand induces different oligomeric forms of RAGE which results in a ligand-specific signal transduction. The structure of mouse RAGE bound to heparan sulfate has been previously determined but the electron density map of heparan sulfate was too ambiguous that the exact position of heparin sulfate could not be defined. Furthermore, the complex structure of human RAGE and heparin sulfate still remains elusive. Therefore, to determine the structure, human RAGE was overexpressed using bacterial expression system and crystallized using the sitting drop method in the condition of 0.1 M sodium acetate trihydrate pH 4.6, 8 % (w/v) polyethylene glycol 4,000 at 290 K. The crystal diffracted to 3.6 Å resolution and the space group is C121 with unit cell parameters a= 206.04 Å, b= 68.64 Å, c= 98.73 Å, α= 90.00°, β= 90.62°, γ= 90.00°.

Modified parity space averaging approaches for online cross-calibration of redundant sensors in nuclear reactors

  • Kassim, Moath;Heo, Gyunyoung
    • Nuclear Engineering and Technology
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    • 제50권4호
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    • pp.589-598
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    • 2018
  • To maintain safety and reliability of reactors, redundant sensors are usually used to measure critical variables and estimate their averaged time-dependency. Nonhealthy sensors can badly influence the estimation result of the process variable. Since online condition monitoring was introduced, the online cross-calibration method has been widely used to detect any anomaly of sensor readings among the redundant group. The cross-calibration method has four main averaging techniques: simple averaging, band averaging, weighted averaging, and parity space averaging (PSA). PSA is used to weigh redundant signals based on their error bounds and their band consistency. Using the consistency weighting factor (C), PSA assigns more weight to consistent signals that have shared bands, based on how many bands they share, and gives inconsistent signals of very low weight. In this article, three approaches are introduced for improving the PSA technique: the first is to add another consistency factor, so called trend consistency (TC), to include a consideration of the preserving of any characteristic edge that reflects the behavior of equipment/component measured by the process parameter; the second approach proposes replacing the error bound/accuracy based weighting factor ($W^a$) with a weighting factor based on the Euclidean distance ($W^d$), and the third approach proposes applying $W^d$, TC, and C, all together. Cold neutron source data sets of four redundant hydrogen pressure transmitters from a research reactor were used to perform the validation and verification. Results showed that the second and third modified approaches lead to reasonable improvement of the PSA technique. All approaches implemented in this study were similar in that they have the capability to (1) identify and isolate a drifted sensor that should undergo calibration, (2) identify a faulty sensor/s due to long and continuous missing data range, and (3) identify a healthy sensor.

Iron-Solubilizing Isolate of Meat : Physiological , Compositional and Physicochemical Characteristics

  • Kim, Yunji;Charles E.Carpenter;Arthur W.Mahoney
    • Preventive Nutrition and Food Science
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    • 제3권1호
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    • pp.1-9
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    • 1998
  • Studies were performed to 1) investigate if ferric iron bound in complex with iron-solubilizing meat components is absorbable, 2) compare the relative iron-solubilizing capaicty of meats, and 3) investigate the physicochemical and compositional characteristics if meat meat has iron-solubilizing components . Iron-solubilizing components of beef were isolate from pH 2 HCL homogenates into dialysis bags(MWCO of 6-8K). Radiolabelled iron complexes were then generated using ferric iron and the isolated low-molecular-weight components(ILC) from undigested beef or ascrobate. The bioavailabilities of radioiron in these complexes or as ferric iron were measured as radioiron absorption into the blood one hour after injection into ligated duodenal lops of rats. Iron absorptions were ferrous -ascorbate complexes(18.8$\pm$2.2%)> ferric-ILC complexes(4.9$\pm$0.6%)>ferric iron (23.2$\pm$0.3%)(p<0.05). ILC from 0.1g of beef, pork, chicken, fish , or egg white were added to 400$\mu$g ferric iron in pH 2 HCL, the pH raised to 7,2, and soluble iron determined in the supernatant after centrifugation at 2,500g for 10 min. Iron solubilizing capabilities of ILC were pork (99.9$\pm$0.1%)>beef(93.6$\pm$3.5%)> chicken (75.8$\pm$1.8%) > fish(64.6%$\pm$3.6%)>egg white(50.9$\pm$0.9%)(p<0.05). The compositional and physico-chemical characteristics of the ILC from the above dietary protein sources were investigated.

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$1{times}8$ 배열, 7.8 $\mu\textrm{m}$ 최대반응 GaAs/AlGaAs 양자우물 적외선 검출기 ($1{times}8$ Array of GaAs/AlGaAs quantum well infrared photodetector with 7.8$\mu\textrm{m}$ peak response)

  • 박은영;최정우;노삼규;최우석;박승한;조태희;홍성철;오병성;이승주
    • 한국광학회지
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    • 제9권6호
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    • pp.428-432
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    • 1998
  • 장파장영역의 적외선 검출을 위해 구속­비구속 상태간 전이를 이용한 GaAs/AlGaAs 이종접합 다중양자우물구조형태 검출기를 제작하여 전기적, 광학적 특성을 살펴보았다. 시료는 MBE를 이용하여 SI-GaAs(100)기판 위에 장벽 500${\AA} $, 폭 40${\AA} $의 양자우물구조를 25층 성장시켰으며, Al의 몰분율은 0.28로 하였고 우물의 중심부 20${\AA} $$2{\times}10^{18}cm^{-3}$의 농도로 Si n-도핑을 하였다. 200$\times$200$\mu\textrm{m}^2$ 면적의 사각형 화소가 되도록 시료를 식각한 후 Au/Ge로 전극을 붙여 1$\times$8 검출기 배열을 제작하였다. 10K의 온도에서 적외선 광원에 대한 광특성을 조사한 결과 1차원으로 배열한 8개의 단일소자 모두 7.8$\mu\textrm{m}$파장에서 최대반응을 보였으며 검출률($D^*$)은 최대 $4.9{\times}10^9cm\sqrt{Hz}/W$이었다.

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유산동(硫酸銅) 중독(中毒)이 랫트 간장(肝臟)의 미세구조(微細構造)에 미치는 영향(影響) (Effects of copper sulfate poisoning on the fine structure of rat liver)

  • 윤화중;이상목;장병준
    • 대한수의학회지
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    • 제30권1호
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    • pp.85-91
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    • 1990
  • This study was designed in order to investigate the effect of copper sulfate to the ultrastructural changes of the hepatocytes in Sprague Dawley rats. The animals were administered with copper sulfate (10mg/kg B.W.), which was dissolved in normal saline. The solution was injected into abdominal cavity every day. The animals were sacrificed at the 6th, 12th, and 24th day from the beginning of administration. The specimens obtained from the liver were observed with electron microscope and significant changes were as follows. 1. A prominent dilatation and disruption of the cisternae of rough endoplasmic reticulum were recognized. Also, the detachment of membrane bound ribosomes was shown. 2. The proliferation of smooth endoplasmic reticulum and the depletion of glycogen particles were noted. 3. The increase of primary lysosomes and autophagic vacuoles was obserbed. 4. The dilatation of mitochondrial cristae was obserbed. And it was irregulary scattered in the stroma of mitochondria. 5. The atrophy of microvilli in the bile canaliculi and space of Disse was prominent. 6. Membrane of hepatocytes was damaged and significant hydrophic degeneration was obserbed in the perisinusoidal regions. 7. The damage of Fat-storing cells was more significant than that of hepatocytes.

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SolidWorks®와 LabVIEW®를 연동한 6축 수직 다관절 로봇의 게인 튜닝 연구 (Technique for Simulating Gain Tuning using SolidWorks® and LabVIEW® for a Six-Axis Articulated Robot)

  • 정창두;정원지;김만수
    • 한국생산제조학회지
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    • 제23권1호
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    • pp.75-82
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    • 2014
  • For accurate gain tuning of the lab-manufactured six-axis articulated robot RS2 with less noise, in this study, a program routine using dynamic signal analyzer, which is a realization of a controller design algorithm in the frequency domain, is programmed using LabVIEW$^{(R)}$. The contribution of this paper is the proposal of a simulation technique based on SolidWorks$^{(R)}$ and LabVIEW$^{(R)}$ for the gain tuning of a six-axis articulated robot. To realize the simulation, the LabVIEW$^{(R)}$ program used for experimental gain tuning is incorporated in to SolidWorks$^{(R)}$. A comparison shows that the results of simulation-based gain tuning and experimental gain tuning are almost the same within a 5% error bound. On the basis of the comparison, it can be suggested that the simulation-based technique for gain tuning can be applied instead of experimental gain tuning to a six-axis articulated robot by interlocking SolidWorks$^{(R)}$ and LabVIEW$^{(R)}$.

밭 토양에서 패화석비료 시용에 따른 유효인산의 증대 (Increased Available Phosphate by Shell Meal Fertilizer Application in Upland Soil)

  • 이창훈;이주영;하병연;김필주
    • 한국토양비료학회지
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    • 제38권1호
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    • pp.52-57
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    • 2005
  • 굴껍질을 주원료로 하는 패화석비료가 토양개량제로서 배추의 생육 및 수량을 증진시키고 토양의 이화학적 특성 개선에 효과가 있는 것으로 알려져 있다. 평택통 (Fine silty, Typic Endoaquepts)의 밭 토양에 굴패화석비료를 0, 4, 8, 12, and $16Mg\;ha^{-1}$ 처리하여 봄배추를 재배하는 과정 중 패화석비료 시용량이 증가함에 따라 토양내 유효인산함량은 일정하게 증가되는 것이 확인되었다. 유효인산 함량의 증가는 1차적으로 패화석비료내 포함된 인산 ($1.5g\;P_2O_5\;kg^{-1}$)의 직접투입이 토양 내 전 인산을 증가시키고 유효인산을 증진시킨 것으로 평가되었다. 그리고 알카리성 제재인 패화석비료가 pH 5.8의 공시토양의 pH를 중성범위로 높이면서 간접적으로 유효인산함량을 증진시킨 것으로 해석되었다. 패화석비료의 시용량이 증가함에 따라 토양내 수용성 인산과 Ca-P 함량을 다소 증가시켰으나, Al-P와 Fe-P의 비율을 크게 감소되었다. 결과적으로 패화석비료는 토양내 유효인산함량 증진에 효과가 있으며, 이렇게 많아진 유효인산을 이용하여 인산시비량을 저감하고 나아가 인산유출을 저감할 수 있는 방법이 될 수 있을 것으로 판단된다.

Kinetic Analysis about the Bidirectional Transport of 1-Anilino-8-naphthalene Sulfonate (ANS) by Isolated Rat Hepatocytes

  • Lee, Pung-Sok;Song, Im-Sook;Shin, Tae-Ha;Chung, Suk-Jae;Shim, Chang-Koo;Song, Sukgil;Chung, Youn-Bok
    • Archives of Pharmacal Research
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    • 제26권4호
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    • pp.338-343
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    • 2003
  • The purpose of the present study was to investigate the bidirectional transport of 1-anilino-8-naphthalene sulfonate (ANS) using isolated rat hepatocytes. The initial uptake rate of ANS by isolated hepatocytes was determined. The uptake process of ANS was saturable, with a $K_m of 29.1\pm3.2 \mu M and V_{max} of 2.9\pm0.1$ mmol/min/mg protein. Subsequently, the initial efflux rate of ANS from isolated hepatocytes was determined by resuspending preloaded cells to 3.0% (w/v) BSA buffer. The efflux process for total ANS revealed a little saturability. The mean value of the efflux clearance was $2.2\pm0.1 \mu$ L/min/mg protein. The efflux rate of ANS from hepatocytes was markedly decreased at $4^{\circ}C$, indicating that the apparent efflux of ANS might not be attributed to the release of ANS bound to the cell surface, but to the efflux of ANS from intracellular space. The efflux clearance was furthermore corrected for the unbound intracellular ANS concentration on the basis of its binding parameters to cytosol. The relation between efflux rate and unbound ANS concentration was fitted well to the Michaelis-Menten equation with a saturable and a nonsaturable components. The $V_{max} and K_m$ values were 0.54 mmol/min/mg protein, and 10.0 $\mu$ M, respectively. Based on the comparison of the ratios of $V_{max} to K_m (V_{max}/K_m)$ corresponding to the transport clearance, the influx clearance was two times higher than the efflux clearance. Together with our preliminary studies that ATP suppression in hepatocytes substantially inhibited ANS influx rate, we concluded that the hepatic uptake of ANS is actively taken up into hepatocytes via the carrier mediated transport system.