• 제목/요약/키워드: Carbon pretreatment

검색결과 270건 처리시간 0.023초

Carbon Monoxide as a Novel Central Pyrogenic Mediator

  • Jang, Choon-Gon;Lee, Seung-Jin;Yang, Sang-In;Kim, Jin-Hak;Sohn, Uy-Dong;Lee, Seok-Yong
    • Archives of Pharmacal Research
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    • 제25권3호
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    • pp.343-348
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    • 2002
  • Carbon monoxide (CO) are produced by heme oxygenase (HO), and HO was detected in hypothalamus. However, the roles of CO produced in hypothalamus was not fully elucidated. So, we tested the effects of CO on body temperature because preoptic-anterior hypothalamus was known as the presumptive primary fever-producing site. CO-saturated aCSF ($4{\;}{\mu}l$, i.c.v.) and hemin ($10{\;}{\mu}g$, i.c.v.) elicited marked febrile response. Pretreatment with indomethacin completely inhibited CO- and hemin-induced fever. Zinc protoporphyrin-IX ($10{\;}{\mu}g$, i.c.v.) or ODQ ($50{\;}{\mu}g$, i.c.v.) partially reduced hemin-induced febrile response. Dibutyryl-cGMP ($100{\;}{\mu}g$, i.c.v.) produced profound febrile response and this febrile response was attenuated by indomethacin. These results indicate that endogenous CO may have a role as a pyrogenic mediator in CNS and CO-mediated pyresis is dependent on prostaglandin production and partially on activation of soluble guanylate cyclase.

정수처리에서 생물활성탄의 전처리로서 고급산화처리법의 평가 (Evaluation of Advanced Oxidation Process(AOP) as a Pretreatment Process of Biological Activated Carbon in Drinking Water Treatment)

  • 김우항
    • 한국환경과학회지
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    • 제8권6호
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    • pp.725-730
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    • 1999
  • The advanced oxidation process (AOP) using ozone combined with hydrogen peroxide and ultraviolet treatment were evaluated for biodegradable dissolved organic carbon (EDOC) formation and dissolved organic carbon (DOC) removal. Oxidation treatment were conducted alone or combination with ozone, hydrogen peroxide and ultraviolet processes. Ozone dosage of ozone process was varied from $0.5mg/l{\ell}\cdot}min$ to $5mg/{\ell}{\cdot}min$. Ozone/hydrogen peroxide process was done using $20mg/{\ell}{\cdot}min$ of hydrogen peroxide concentration. Ozone/ultraviolet process was irradiated with $12mW/cm^2$ of density and 254nm. Ozone dosage was varied from $0.5mg/{\ell}{\cdot}min$ to $5mg/{\ell}{\cdot}min$ at the ozone/hydrogen peroxide and ozone/ultraviolet processes too. Contact time of all the process was 20 minutes. Oxidation treatment were performed on microfiltration effluent samples. BDOC formation was reached to an optimum at ozone dosage of $1.5mg/{\ell}{\cdot}min$ in the ozone/hydrogen peroxide process and $1mg/{\ell}{\cdot}min$ in ozone/ultraviolet process, after which BDOC formation was decreased at higher ozone dosages. But BDOC formation was increased with ozone dosages increasing in ozone process. The efficiency of DOC removal was higher AOPs than ozone process. Ozone/ultraviolet proces was the highest for DOC removal efficiency in each process. THMFP. removal efficiency by ozone/ultraviolet process was higher than that by each of ozone process and ozone/hydrogen peroxide process.

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기판의 코로나 표면처리에 의한 탄소 나노튜브 투명전극의 물성 향상 (Improvement of Transparent Electrodes Based on Carbon Nanotubes Via Corona Treatment on Substrate Surface)

  • 한상훈;김부종;박진석
    • 반도체디스플레이기술학회지
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    • 제13권1호
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    • pp.7-12
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    • 2014
  • In this study, we investigate the effects of corona-discharge pre-treatment on the properties of carbon nanotubes (CNTs) which are used as flexible transparent electrodes. The CNTs are deposited on PET (polyethylene terephthalate) substrates using a spray coating method. Prior to the deposition of CNTs, the PET substrates are corona-treated by varying the feeding directions of the PET substrate and the numbers of treatments. The variations in the surface morphologies and roughnesses of the PET substrates due to corona-treatment are characterized via atomic force microscopy (AFM). Dynamic contact angles (DCAs) of the corona-treated PET substrates are measured and analyzed as functions of the treatment conditions. Also, the sheet resistances and visible-range transmittances of the CNTs deposited on PET substrates are measured before and after bending test. The experimental results obtained in this study provide strong evidences that the adhesive forces between CNTs and PET substrates can be substantially enhanced by corona-discharge pretreatment.

Comparison of Ethanol Yield Coefficients Using Saccharomyces cerevisiae, Candida lusitaniae, and Kluyveromyces marxianus Adapted to High Concentrations of Galactose with Gracilaria verrucosa as Substrate

  • Park, Yurim;Sunwoo, In Yung;Yang, Jiwon;Jeong, Gwi-Teak;Kim, Sung-Koo
    • Journal of Microbiology and Biotechnology
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    • 제30권6호
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    • pp.930-936
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    • 2020
  • The red seaweed Gracilaria verrucosa has been used for the production of bioethanol. Pretreatment for monosaccharide production was carried out with 12% (w/v) G. verrucosa slurry and 500 mM HNO3 at 121℃ for 90 min. Enzymatic hydrolysis was performed with a mixture of commercial enzymes (Cellic C-Tec 2 and Celluclast 1.5 L; 16 U/ml) at 50℃ and 150 rpm for 48 h. G. verrucosa was composed of 66.9% carbohydrates. In this study, 61.0 g/L monosaccharides were obtained from 120.0 g dw/l G. verrucosa. The fermentation inhibitors such as hydroxymethylfurfural (HMF), levulinic acid, and formic acid were produced during pretreatment. Activated carbon was used to remove HMF. Wild-type and adaptively evolved Saccharomyces cerevisiae, Candida lusitaniae, and Kluyveromyces marxianus were used for fermentation to evaluate ethanol production.

건조 전처리 방법으로써 초임계 이산화탄소가 사과절편의 화학적 성분에 미치는 영향 (Changes in The Chemical Composition of Apple Slices Pretreated with Supercritical Carbon Dioxide)

  • 이보수;이원영
    • 한국식품저장유통학회지
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    • 제17권2호
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    • pp.256-260
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    • 2010
  • 초임계 이산화탄소를 건조 전처리 방법으로 사용하여 사과의 성분변화를 관찰하였다. 총 페놀 함량은 초임계 이산화탄소 온도와 압력이 증가 할수록 생과일과 무처리구 보다 낮은 함량을 나타내었다. Vitamin C, 유리당 및 유기산의 함량은 전처리 구간이 무처리구 보다 낮았고, 초임계 이산화탄소 압력과 온도 따라 큰 차이는 없었다. 이와 같은 결과는 초임계 이산화탄소의 용매적 특성이 핵산에 가까워 극성물질에 대한 용해력이 높지 않은 상태에서 고압으로 인해 압착되고 고압을 제거할 때 식품성분들이 이산화탄소와 동반해 유리되기 때문인 것으로 생각된다.

Effect of Biphenyl Dimethyl Dicarboxylate on Chemical-Induced Hepatotoxicity

  • Kim, Sun-Hyung;Cho, Young-Jin;Bae, Yong-Jin;Lee, Kweon-Haeng;Lee, Sang-Bok
    • Toxicological Research
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    • 제11권2호
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    • pp.181-185
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    • 1995
  • To know the mechanism of biphenyl dimethyl dicarboxylate (DDB) in the protection of chemically induced hepatotoxicity, the activity of glutamic pyruvic tran.saminase (GPT) and the level of lipid peroxidation metabolite (malondialdehyde, MDA) and ATP content in hepatocytes were determined in serum and primarily cultured hepatocytes. For in vibo study, rats were pretreated with DDB (300 mg/ kg, p.o.)for 7 days. DDB pretreatment efficiently reduced the elevation of serum GPT activity induced by carbon tetrachloride (1.6 ml/kg, s.c.) and acetaminophen administration (1500 mg/kg, i.p.). In ex vivo study, hepatocytes were isolated from the rats pretreated with DDB (300 mg/kg, p.o.)for 7 days and cultured for 12 hrs before inducing cytotoxicity with chemicals. The MDA formation and the GPT release induced by adriamycin $(1\times10^{-4} mg/ml)$ and cisplatin $(2\times10^{-4} mg/ml)$ were markedly decreased in the hepatocytes from the rats pretreated with DDB as compared to vehicle only. However, DDB pretreatment did not prevent the decrease of ATP contents of hepatocytes induced by cisplatin and adriamycin. In in vitro experiment, DDB was pretreated in primary cultured hepatocytes for 3 days. DDB enhanced the decreases of ATP contents induced by cisplatin and adriamycln. These results suggest that DDB may protect the hepatocytes from injury induced by hepatotoxlcants through inhibiting the lipid peroxidation.

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역삼투 공정 파울링 지표로서 SDI(Silt Density Index)의 적합성 검증 (Verification of Silt Density Index (SDI) as a fouling index for reverse osmosis (RO) feed water)

  • 김수한;김충환;강석형;이원태;임재림
    • 상하수도학회지
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    • 제25권4호
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    • pp.489-495
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    • 2011
  • Silt Density Index (SDI) has been used as a fouling index for reverse osmosis (RO) processes for decades. In order to decrease RO fouling, feed water should meet SDI standard, which was used to select a proper pretreatment system for RO processes. However, SDI is supposed to be sensitive only to particles larger than 0.45 ${\mu}m$ in terms of diameters while nanoparticles and dissolved organic matter can be potent foulants for RO processes. Our study started from the suspected performance of SDI as a RO fouling index. SDI data from pilot plants located world wide including South Korea were collected and analyzed. Suspended partcle concentration (i.e., turbidity and particle counts), and dissolved organic matter concentration (i.e., dissolved orgnaic carbon (DOC) concentration) data were also collected and compared to SDI values of same water samples. We found that SDI values were not only affected by suspended particle concentration but also by dissolved organic matter concentration. Therefore SDI can be used as a reasonable fouling index for RO feed water because the main foulants for RO processes are suspended particle and dissolved organic matter.

Simultaneous Electroanalysis of Nitric Oxide and Nitrite

  • Oritani, Tadato;Okajima, Takeyoshi;Kitamura, Fusao;Ohsaka, Takeo
    • 전기화학회지
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    • 제5권4호
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    • pp.209-211
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    • 2002
  • The simultaneous sensing of nitric oxide (NO) and its metabolite, nitrite $(NO_2^-)$ has been studied by Osteryoung square-wave voltarnmetery (OSWV) in physiological pH solution (0.1 M phosphate buffer solution, pH 7.2). Using an electrochemically pretreated glassy carbon (GC) electrode, OSWV was successfully applied to observe the well-separated oxidation peaks at ca. 0.58 and 0.80V vs. Ag/AgCI for NO and $(NO_2^-)$, respectively. This clear separation between the NO and $(NO_2^-)$ oxidation peaks may be due to the formation of surface oxides (e.g., quinone (C=O) or carboxylic $(COO^-)$ group) and surface defects introduced by the electrochemical pretreatment of GC electrodes.

Optimization of Anaerobic Process by Enzyme Treatment of High Concentration Organic Substances in Food Wastewater

  • Tae-Hwan JEONG;Woo-Taeg KWON
    • 웰빙융합연구
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    • 제6권2호
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    • pp.33-37
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    • 2023
  • Purpose: Since 2013, marine dumping of wastewater has been banned, and research on eco-friendly and efficient land treatment has emerged. This study compared and tested changes in biogas production and anaerobic process efficiency depending on whether or not enzyme pretreatment was performed during anaerobic digestion from single-phase and two-phase to medium-temperature. Research design, data and methodology: The total sugar, direct sugar, pH, and acidity before and after fermentation were analyzed by G/C by anaerobic fermentation of the liquor wastewater, food wastewater 1, and food wastewater 2 at 30℃ for 67 hours, and the amount of methane gas generated was analyzed by balloon volume. Results: It was found that stable organic acid concentration and pH were found in the enzyme-treated food wastewater 2, and the amount of methane gas generated was also increased. Conclusions: When anaerobic digestion of the liquor wastewater and the food wastewater together, the performance of enzyme pretreatment resulted in increased digestive efficiency. It will be the basic data that can contribute to carbon neutrality and greenhouse gas reduction by increasing the production of biogas.

흰쥐에 있어서 사염화탄소에 의한 간손상에 allopurinol의 영향 (Effect of Allopurinol Pretreatment on the Liver Damage in $CCl_4$-treated Rat)

  • 배지혜;윤종국;이상일
    • Toxicological Research
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    • 제11권2호
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    • pp.247-252
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    • 1995
  • To evaluate the effect of xanthine oxidase on liver injury by $CCl_4$, liver damage was induced both in allopurinol pretreated rats (500 mg/kg. ip) and control group by twice intraperitoneal injection of $CCl_4$ (0.1 ml/100 g body wt. 50% in olive oil) at interval of one day. Increases in the levels of serum alanine aminotransferase and liver weight/body weight (%) by $CCl_4$ were significantly smaller inallopurinol pretreated rats than in control whereas the hepatic microsomal glucose-6-pholphatase activities were significantly higher in allopurinol pretreated rats than control group by $CCl_4$ treatment. These results indicates that allopurinol pretreatment may reduce the liver damage in $CCl_4$ intoxicated rats. In rats either with $CCl_4$or not, hepatic type O xanthine oxidase activities were significantly reduced by allopurinol pretreatment and the increasing rate of these enzymes to each control was remarkably lower in allopurinol pretreated rats than control. Liver cytosolic protein contents and aniline hydroxylase, aminopyrine demethylase activities were higher in allopurinol pretreated rats than coirol rats when animals were treated with $CCl_4$. On the other hand, neither allopurinol pretreated nor $CCl_4$ treatment caused any significant changes in hepatic superoxide dismutase and catalase activities. Hepatic glutathione contents were higher in $CCl_4$-treated rats than control, but no significant changes were found in both between the allopurinol treated rats and $CCl_4$-treated rats pretreated with allopurinol, and glutathione and glutathione S-transferase activities were significantly reduced in $CCl_4$-treated rats than control whereas these enzyme activities showed on significant change in both between allopurinel treated and $CCl_4$-treated rats pretreated with allopurinol. It is concluded that xanthine oxidase reaction system augment $CCl_4$ induced liver injury via even oxygen free radical system.

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