• Title/Summary/Keyword: pretreatments

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Effect of nifedipine against carrageenan-induced paw oedema in rats (흰쥐에서 carrageenan에 의한 족부종(足浮腫)에 대한 nifedipine의 영향)

  • Shin, Dong-ho
    • Korean Journal of Veterinary Research
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    • v.30 no.3
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    • pp.283-286
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    • 1990
  • The effects of nifedipne and verapamil were compared on carrageenan-induced paw edema in rats and the results are summarized as follows: Carrageenan induced severe acute paw edema within 30 minutes and the maximum effect was achieved around 4 hours after administration. The carrageenan-induced paw edema was prominantly reduced by pretreatments of indomethacin (2mg/kg, p.o.) and nifedipine (10 and 20mg/kg, i.p.), whereas verapamil had no effect on the carrageenan-induced paw edema. These results suggest that calcium antagonists, nifedipine and verapamil, have a different effect on the inflammatory response induced by carrageenan.

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Shrinkages of Prefrozen or Presteamed Wood (전처리(前處理) 목재(木材)의 수축율(收縮率) 변화(變化))

  • Kang, Ho-Yang
    • Journal of the Korean Wood Science and Technology
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    • v.22 no.1
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    • pp.66-71
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    • 1994
  • To increase drying rate and reduce drying degradation, pretreatments such as prefreezing and presteaming have been widely used in wood industries. Presteaming lumbers prior to kiln drying is known positively to improve its permeability, to increase diffusion coefficient and to reduce discoloration, but negatively to increase collapse. Prefreezing lumbers prior to kiln drying is also known to reduce significantly its drying defects and its shrinkages. Thus it is no doubt that the pretreated lumbers shrink diversely from the untreated. In this study the shrinkage behaviors of the pretreated specimens are investigated by drying two tropical hardwoods (Apitong and Taun) in three different dying conditions: high temperature and slow drying rate (drying in a closed cylinder), high temperature and rapid drying rate (drying in an oven) and low temperature and slow drying rate(drying at room temperature). The prefrozen specimens show the least volumetric shrinkages in most drying conditions. The specimens dried in cylinders shrink most among all drying conditions. In general the pretreated specimens reached the 30 % moisture content faster than the untreated by about 30 %.

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Sugar Extraction by Pretreatment and Soda Pulping From Cattail (Typha latifolia L.) (1) Extraction of Sugar (부들의 전처리를 통한 당의 추출과 소다펄프화에 관한 연구 (1) 당 추출)

  • Lee, Sung-Eun;Kim, Wan-Jung;Son, Mi-Kyung;Seo, Yung-Bum
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.2
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    • pp.88-94
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    • 2010
  • Cattail (Typha L.) was used as a raw material for producing both bio-ethanol and pulp for papermaking at the same time. Pretreatments of cattail stems and leaves with acid ($H_2SO_4$) and alkali (NaOH) in three different addition levels were studied before soda pulping. The acid pretreatment gave reducing sugar of 15.2% of initial weight, but alkali pretreatment close to 1%. Soda pulping of the pretreated cattail gave 3% reduction in pulp yield and less bonding properties in paper; however, refining of the pulp from the pretreated cattail with alkali restored their fiber bondings up to that of the pulp from no-pretreated cattail at equivalent freeness.

A Study on the Hypotensive Action of Astragali Radix Water Extract in the Rabbit (황기의 혈압강하 작용에 관한 연구)

  • 임동윤
    • YAKHAK HOEJI
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    • v.23 no.2
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    • pp.69-80
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    • 1979
  • Effects of Astragali Radix Water Extract (ARWE) on the blood pressure were investigated in the whole rabbit and the spinalized rabbit. ARWE, when administered into the ear-vein or lateral ventricle, produced a fall in the blood pressure in the whole rabbit, but intravenous ARWE in the spinalized rabbit did not elicite the hypotensive action. Pretreatments with chlorisondamine, guanethidine, phentolamine and cyproheptadine in the whole rabbit weakened the depressor action of ARWE. The hypotensive action of the whole rabbit to ARWE was not influenced by the pretreatment of the animals with diphennylhydramine, propranolol, and vagotomization, whereas inhibited by atropine. ARWE did not affect the pressor response by angiotensin. However, it enhanced the hypertensive action by norepineprine and reduced the elevation in the blood pressure by carotid occlusion in the whole rabbit. These experimental observations suggest that ARWE may cause the depressor response via mechanisms of the central sympathetic blocking action, cholinergic action by peripheral origin and serotonin-like action.

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Development of Al plasma assisted chemical vapor deposition using DMEAA (DMEAA를 이용한 알루미늄 PACVD법의 개발)

  • 김동찬;김병윤;이병일;김동환;주승기
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.10
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    • pp.98-106
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    • 1996
  • A thin film of aluminum for ultra large scale integrated circuits metalization has been deposited on TiN and SiO$_{2}$ substrates by plasma assisted chemical vapor deposition using DMEAA (dimenthylethylamine alane) as a precursor. The effects of plasma on surface topology and growth characteristics were investigated. Thermal CVD Al could not be got continuous films on insulating subsrate such as SiO$_{2}$. However, it was found that Al films could be deposited on SiO$_{2}$ substate without any pretreatments by the hydrogen plasma for pyrolysis of DMEAA. Compared to the thermal CVD, PACVD films showed much better reflectance and resistance on TiN and SiO$_{2}$ substrate. We obtained mirror-like PACVD Al film of 90% reflectance and resistance on TiN and SiO$_{2}$ substrates. We obtained mirror-like PACVD Al film of 90% reflectance on TiN substrate. Excellent conformal step coverage was obtained on submicron contact holes ;by the PACVD blanket deposition.

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Organic thin-film transistors and circuits manufactured by sub-femtoliter inkjets

  • Someya, Takao;Sekitani, Tsuyoshi;Noguchi, Yoshiaki;Yokota, Tomoyuki;Klauk, Hagen;Zschieschang, Ute
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1229-1232
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    • 2008
  • We have successfully manufactured high-quality top-contact organic thin-film transistors using inkjet technologies with sub-femtoliter droplet volume. Silver fine lines were directly patterned by inkjet on pentacene channel layers. The minimum width of silver lines was $1{\mu}m$ with without the need for pre-patterning or surface pretreatments. The mobility was $0.3\;cm^2/Vs$.

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Effect of Ginseng Saponins on the Amount of Catecholamine Neurotransmitters in Carbon Monoxide-intoxicated Rats and Aged Rats (인삼 사포닌이 일산화탄소중독 및 노화과정에서 흰쥐의 신경전달물질 함량 변화에 미치는 영향)

  • Park, Hea-Young;Kim, Choon-Mi;Ju, Ji-Yeon;Choi, Hyun-Jin
    • YAKHAK HOEJI
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    • v.36 no.3
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    • pp.285-290
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    • 1992
  • After rats were exposed to 5,000 ppm carbon monoxide for 30 minutes, the amounts of catecholamine neurotransmitters in stratum were measured using high performance liquid chromatograph equipped with electrochemical detector. The concentration of dopamine in stratum was significantly decreased after carbon monoxide intoxification, but those of dihydroxyphenylacetic acid, norepinephrine, and epinephrine was not changed. However the pretreatments of Ginseng total saponin and panaxatriol saponin increased the concentrations of dopamine and its acidic metabolites (DOPAC and HVA). Ginseng total saponin also increased the concentrations of norepinephrine and epinephrine. Similar results were obtained from aged rats.

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Effects of Solubilization Pretreatment of Wastewater Sludge on Anaerobic Digestion (하수슬러지의 혐기성 소화에 미치는 가용화 전처리의 효과)

  • Park, Ki Young;Kim, Dae Young;Chung, Tai Hak
    • Journal of Korean Society of Water and Wastewater
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    • v.14 no.1
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    • pp.117-126
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    • 2000
  • Solubilization pretreatments were conducted to enhance the anaerobic digestion of the waste activated sludge. Four pretreatment techniques including heating, sonication freezing and thawing, and enzyme addition were employed to solubilize the waste activated sludge under various conditions. Thermal pretreatment by heating showed the highest efficiency compared with other methods, and freezing and thawing was confirmed as a feasible alternative of solubilization as well as the pretreatment of dewatering. There is a clear correlation between the solubilization efficiency of the waste activated sludge and the gas production. Batch digestion results showed the cumulative gas production as much as four times after thermal pretreatment as compared with that by the control sludge without pretreatment. As a result, hydrolysis or solubilization pretreatment might play a significant role in the high rate digestion of the waste activated sludge.

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Effect of Histamine $H_2$ Antagonist on Pharmacokinetics of Caffeine(I) (카페인의 약물동태에 미치는 히스타민 $H_2$ 길항제의 영향(I))

  • Yang, Jae-Hean;Kang, In-Ho
    • Journal of Pharmaceutical Investigation
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    • v.17 no.4
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    • pp.189-195
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    • 1987
  • The effects of cimetidine or ranitidine pretreatment on the intestinal absorption, plasma and urine level of caffeine, gastric acidity of mouse, and sleeping time by hexobarbital sodium were investigated pharmacokinetically. Cimetidine and ranitidine pretreatments were found to increase both the rate and extent of absorption of caffeine in rats. Cimetidine pretreatment increased blood level of caffeine and decreased urine level, while ranitidine pretreatment had no effect on urine level of caffeine. Ranitidine pretreatment inhibited gastric secretion due to caffeine more than cimetidine pretreatment. Cimetidine pretreatment increased the action of caffeine and showed shorter sleeping time by hexobarbital sodium, comparing with ranitidine pretreatment.

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Anticonvulsant Effect of Uncariae Ramulus et Uncus II. - Effects of Methanol Extract and Ethyl Acetate Fraction on Neurotransmitters related Components in Brain - (조구등 성분의 항경련효과 II. - 메탄올 추출물 및 에틸 아세테이트 분획의 뇌 신경전달 관련물질에 미치는 효과 -)

  • Kim, Dong-Young;Park, Jong-Cheol;Lee, Chung-Kyu;Choi, Jong-Won
    • Korean Journal of Pharmacognosy
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    • v.29 no.3
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    • pp.179-186
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    • 1998
  • The fractions of Uncariae Ramulus et Uncus seemed to be closely related with the levels of amino acids and other components which concerns with formation and metabolism of neurotransmitters in brain. The pretreatments of methanolic extract and its fractions prohibited the pentylenetetrazole (PTZ) induced convulsion. In such cases, lowered levels of ${\gamma}-aminobutyric$ acid and glutathione in brain were significantly recovered. And also the increased levels or activities of lipid peroxide, ${\gamma}-aminobutyric$ acid aminotransferase, xanthine oxidase, aldehyde oxidase, superoxide dismutase, catalase and glutathione peroxidase by PTZ-convulsion were lowered to normal state.

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