• 제목/요약/키워드: Pretreatment effect

검색결과 1,883건 처리시간 0.026초

VOCs 연소를 위한 자동차 폐촉매의 전처리 효과 (Pretreatment Effect of Waste Automotive Catalysts for VOCs Combustion)

  • 문정선
    • 한국대기환경학회지
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    • 제16권2호
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    • pp.191-198
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    • 2000
  • For a characterization of the pretreated waste automotive catalyst the following analysis techniques were applied : EA(Elemental Analysis) BET(Brunaure-Emmett-Teller) and ICP-AES(Inductively Coupled Plasma-Atomic Emission Spectrometry). The combustion activity of waste automotive catalyst was investigated for methanol acetaldehyde and toluene as model VOCs in a fixed bed reactor. carbon deposit amount was decreased with increasing catalyst showed a good catalytic activity for VOCs combustion at 40$0^{\circ}C$. Catalytic activity for methanol acetaldehyde and toluence combustion was very excellent and decreased with mileage. The catalytic activity of a waste automotive catalyst for methanol combustion increased after acid treatment. The acid effect of catalytic activity was summarized as follows: HNO3>HCI>H2SO4>CH3COOH. The waste automotive catalyst regenerated by the pretreatment method might have a excellent catalytic activity for VOCs combustion.

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키토산 사전 처리가 면과 견직물의 소목 염색에 미치는 영향 - 키토산의 분자량 변화에 따른 효과 - (Effect of Chitosan Pretreatment on the Dyeing of Cotton and Silk Fabrics using Caesalpinia sappan - Effect of the Change in Chitosan Molecular Weight -)

  • 최인려;김종준;전동원
    • 복식문화연구
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    • 제13권4호
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    • pp.576-588
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    • 2005
  • The effect of chitosan pretreatment on the dyeing of cotton fiber and silk fiber was investigated. However, it has been difficult to evaluate the effect of the chitosan precisely, since the characterization of the molecular weight and effect of the degree of deacetylation were not elucidated for the application. The treatment effect may change diversely since the chitosan solution viscosity differs a lot based on the chitosan molecular weight. In this study, three chitosan specimens, varying in molecular weight, were applied for the fabric pretreatment in order to investigate the effect of chitosan molecular weight. Also, in order to maximize the efficacy of the chitosan, highly deacetylated chitosan specimens, meeting the deacetylation degree of $100\%$, were selected far the application. The air-permeability change according to the chitosan molecular weight change, influence on the mordanting, color change, and wash fastness change were investigated.

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Effects of Thermal Pretreatment Temperature on the Solubilization Characteristics of Dairy Manure for Dry Anaerobic Digestion

  • Ahn, Heekwon;Lee, Seunghun;Kim, Eunjong;Lee, Jaehee;Sung, Yongjoo
    • 한국토양비료학회지
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    • 제47권2호
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    • pp.127-132
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    • 2014
  • The effect of thermal pretreatment conditions on hydrolysis characteristics of dairy manure and sawdust mixtures has been evaluated. Thermal pretreatment temperature varied between 35 and $120^{\circ}C$ and the period of the treatment changed between 30 and 1440min (24h). As thermal pretreatment temperature and duration increased, organic material solublization rates were improved. Maximum solubilizations of chemical oxygen demand (SCOD), carbohydrates, and volatile fatty acids(VFAs) were observed when dairy manure treated for one day at $120^{\circ}C$. Although one day treatment duration at $120^{\circ}C$ showed the highest SCOD, soluble carbohydrates, and VFAs concentration, its hydrolysis rate was only about 12%. The results reveal that the thermal pretreatment conditions tried in this study are not enough to solubilize the organic matter contained in dairy manure and sawdust mixtures. In order to maximize hydrolysis performance, the further research needs to determine the factors influences on organic material solubilization in addition to thermal pretreatment temperature and duration.

Effect of Different Pretreatment Methods on the Bioconversion of Rice Bran into Ethanol

  • Eyini, M.;Rajapandy, V.;Parani, K.;Lee, Min-Woong
    • Mycobiology
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    • 제32권4호
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    • pp.170-172
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    • 2004
  • The efficiency of acid, enzyme and microbial pretreatment of rice bran was compared based on the content of cellulose, hemicellulose, reducing sugars and xylose in the substrate. An isolate of Aspergillus niger or a strain of Trichoderma viride(MTCC 800) was employed for microbial pretreatment of rice bran in solid state. Acid pretreatment resulted in the highest amount of reducing sugars followed by enzyme and microbial pretreatment. A. niger showed a higher rate of hydrolysis than T. viride. The rice bran hydrolysate obtained from the different methods was subsequently fermented to ethanol either by Zymomonas mobilis(NCIM 806) or by Pichia stipitis(NCIM 3497). P. stipitis fermentation resulted in higher ethanol(37% higher) and biomass production($76{\sim}83%$ higher) than those of Z. mobilis. Maximum ethanol production resulted at 12h in Zymomonas fermentation, while in Pichia fermentation, it was observed at 60h. Microbial pretreatment of rice bran by A. niger followed by fermentation employing P. stipitis was more efficient but slower than the other microbial pretreatment and fermentation.

고혈당(高血糖) 쥐의 췌장(膵臟) 효소활성(酵素活性)에 미치는 생진양혈탕(生津養血湯)의 영향(影響) (Pretreatment with SAENGCHINYANGHYOLTANG to prevent the pancreatic enzymes changes by streptozotocin in rats)

  • 김신석;최종원;이철완
    • 대한한의학회지
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    • 제15권2호
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    • pp.429-444
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    • 1994
  • The present study was undertaken in order to elucidate the effect of pretreatment with Saengchinyanghyoltang(SYT) on changes in serum glucose level, body weight. water consumption. serum insulin concentration and activities of pancreatic enzymes in rats treated with streptozocin(STZ)-induced diabetic state. Histological studies were also carried out to elevate the effects on pancreatic tissues and Langelhans islet cells. SYT pretreatment in STZ diabetic rats inhibited the rise of fasting serum glucose concentration and water consumption. Pretreatment with SYT significantly increased the concentration of blood insulin and body weight changes compared to the STZ-treated group. Pancreatic lipase and trypsin activities were increased. but amylase activity was decreased and pancreatic ${\beta}-cell$ was destroyed by STZ but. pretreatment with SYT prevented these STZ-induced changes.

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Testosterone 및 Estrogen 투여(投與)가 자궁수축약(子宮收縮藥)의 적출자궁(摘出子宮) 수축성(收縮性)에 미치는 영향(影響)과 자궁근내(子宮筋內) Cholinesterase 활성도(活性度) 및 전해질(電解質)에 미치는 효과(?果) (Influences of Testosterone and Estrogen on the Contractile Sensitivity to Oxytocics, the Cholinesterase activity and Electrolytes of the Uterine Muscle of Rabbits)

  • 구희수;공화순;김순영;송현섭;이증자
    • 대한약리학회지
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    • 제6권1호
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    • pp.45-55
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    • 1970
  • It is well known that the uterine contractility is affected by sexual hormone. In this experiment, the authors attempted to study the influences of testosterone and estrogen or the uterine contractility to oxytocics. The contractile sensitivity of the excised uterine muscle of non-castrated and castrated rabbits with testosterone and estrogen 24 hours before experiment is observed respectively. And the cholinesterase activity and electrolytes (Na, K, Ca and Mg) in the uterine muscle are measured in order to study the relationship with contractile sensitivity and those changes. The results obtained were summarized as follows: 1. The contractile effect of spareng on the excised uterine muscle of non-castrated rabbits pretreated with estrogen was markedly increased in small dose, but that of rabbits pretreated with testosterone was significantly increased in large dose, comparing with that of the control group. In castrated rabbits, the contractile sensitivity of the uterine muscle to spareng was significantly increased by pretreatment with estrogen in large dose but it was markedly decreased by pretreatment with testosterone in small dose. 2. The contractile effect of quinine on the excised uterine muscle of non-castrated rabbits pretreated with estrogen was significantly decreased but that of castrated rabbits pretreated with both estrogen and testosterone were markedly increased comparing with that of the control group. 3. The cholinesterase activity in the uterine muscle of non-castrated rabbits was significantly increased by pretreatment with small dose of estrogen or large dose of testosterone, but that of castrated rabbits was markedly decreased by pretreatment with large dose of estrogen. 4. Na and K contents in the uterine muscle of non-castrated rabbits were markedly increased by pretreatment with both estrogen and testosterone, but that of castrated rabbits was significantly increased by pretreatment with small dose of estrogen. 5. Ca content in uterine muscle of non-castrated rabbits was significantly decreased by pretreatment with both large dose of estrogen and testosterone but increased by pretreatment of testosterone. In castrated rabbits, Ca content was significantly decreased by pretreatment with both estrogen and testosterone. 6. Mg content in the uterine muscle of non-castrated rabbits was markedly increased by pretreatment with estrogen and small dose of testosterone, but that of castrated rabbits was significantly decreased by pretreatment with both large dose of estrogen and testosterone.

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Upregulation of IP-10(CXCL10) mRNA Expression by Interleukin-18

  • ;김희선
    • Journal of Yeungnam Medical Science
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    • 제24권1호
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    • pp.67-78
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    • 2007
  • Interferon-${\gamma}$ (IFN-${\gamma}$)의 주된 생산세포는 림프구이며 주로 Interleukin-18(IL-18)에 의해 생산이 된다. IP-10은 IFN-${\gamma}$에 의해 유도, 생산되는 대표적인 케모카인이다. 따라서 본 연구는 마우스 복강내 대식세포에서의 IL-18에 의한 IP-10의 생산 여부를 관찰하고자하였다. IL-18은 마우스 복강내 대식세포에서 IP-10의 발현을 직접적으로 유도 하지는 않았다. 그러나 대식세포에 지다당질을 처리하기 전 IL-18을 전 처리 시킨 결과 지다당질에 의해 유도된 IP-10의 발현이 항진되어 나타남을 확인하였다. 이러한 항진 효과는 IL-18 전처리 16시간에 나타났으며, 이때 NF-${\kappa}B$의 활성이 IP-10의 발현 항진과 일치함을 확인하였다. 비록 IL-18이 IP-10을 직접적으로 발현시키지는 못하나 NF-${\kappa}B$의 활성을 통하여 IL-18의 적정시간에 따른 전 처리시 IP-10 발현의 항진은 케모카인 발현에있어 IL-18의 작용기전을 이해하는데 유용한 자료가 될 것이다.

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승마추출물이 흰쥐의 사염화탄소 유발 간독성에 미치는 효과 (The Effect of Cimicifuga heracleifolia on Carben Tetrachloride-induced Hepatotoxicity in Rats)

  • 정기화;정춘식;노혜림
    • Biomolecules & Therapeutics
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    • 제4권1호
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    • pp.89-96
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    • 1996
  • The effect of Cimicifuga heracleifolia on CC1$_4$-induced hepatotoxicity was investigated. Cimicifuga heracleifolia has been used to diaphoresis, antipyretics and detoxification in oriental remedy. We examined the effect of Cimicifuga heracleifolia methanol extract by blood chemical analysis and histopathologic examination. ALT and AST were decreased by 38% and 67% in pretreatment group of Cimicifuga heracleifolia compared to CC1$_4$control group respectively. There were significant changes neither in total protein, albumin, triglyceride and cholesterol nor in BUN and creatinine. In histopathologic examination, there were severe necrosis and hemorrhage with infiltration of inflammatory cells around the central vein, zone 3 in the liver of CC1$_4$ treated rat. Ballooning degeneration of hepatocytes were frequently noted in the periphery of the hemorrhagic necrosis. In Cimicifuga heracleifolia pretreatment group, we observed mild degree of ballooning degeneration and inflammatory cell infiltration. No gross necrosis was observed. We measured malondialdehyde (MDA) formation by TBA method. It showed that the formation of MDA in Cimicifuga heracleifolia pretreatment group was decreased compared to the $CCl_4$control group. We got the result of the effect of Cimicifuga heracleifolia on CC1$_4$-induced hepatotoxicity by decreasing serum ALT and AST. It seems that the decrease of lipid peroxidation is related to the recovery effect.

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Pretreatment Hepatoprotective Effect of Regular Aerobic Training Against Hepatic Toxicity Induced by Doxorubicin In Rats

  • Zolfagharzadeh, Fatemeh;Roshan, Valiollah Dabidi
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권5호
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    • pp.2931-2936
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    • 2013
  • Background: Doxorubicin is an anthracycline antibiotic commonly used to treat a variety of cancers as a most effective antitumor. However, its clinical use is associated with the toxic effects in numerous healthy tissues. Here we investigated the pretreatment effect of regular aerobic exercise on oxidative stress in rats acutely exposed to DOX-induced hepatotoxicity. Materials and Methods: Forty-eight Wistar male rats were randomly divided into 2 groups: control and training. The training protocol included treadmill running between 25 to 54 min/day and 15 to 20m/min, 5 days/week for 6 weeks. At the end of the exercise training protocol, rats from the control and trained groups were again randomly separated into 3 subgroups: DOX10mg/kg, DOX20mg/kg and saline. All treatments were carried 24 h after the last exercise bout and animals were sacrificed 24 h after DOX and saline injections. Results: Administration of DOX (10 and 20 $mg.kg^{-1}$) resulted in imbalance in biomarkers related to oxidants and antioxidants in liver tissue, as compared to control groups. Six weeks of pretreatment training led to a significant increase in nitric oxide (NO), superoxide dismutase (SOD) and glutathione peroxidase (GPX) as compared to the control+DOX 10 mg/kg group. Training before DOX 20 mg/kg administration also led to a significant increase in NO and SOD, and a significant decrease in malondialdehyde (MDA). In addition, there was a significant difference between DOX 10 mg/kg and DOX 20 mg/kg treatments in MDA levels, only. Conclusions: The results of the present study indicate that pretreatment with aerobic exercise induces positive adaptations and has a potential protective effect against doxorubicin (DOX)-induced hepatotoxicity with doses of 10 and 20 mg.kg.

The effect of a desensitizer and $CO_2$ laser irradiation on bond performance between eroded dentin and resin composite

  • Ding, Meng;Shin, Sang-Wan;Kim, Min-Soo;Ryu, Jae-Jun;Lee, Jeong-Yol
    • The Journal of Advanced Prosthodontics
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    • 제6권3호
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    • pp.165-170
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    • 2014
  • PURPOSE. This study was aimed to evaluate effect of the desensitizing pretreatments on the micro-tensile bond strengths (${\mu}TBS$) to eroded dentin and sound dentin. MATERIALS AND METHODS. Forty-two extracted molars were prepared to form a flat dentin surface, and then they were divided into two groups. Group I was stored in distilled water while group II was subjected to a pH cycling. Each group was then subdivided into three subgroups according to desensitizing pretreatment used: a) pretreatment with desensitizer (Gluma); b) pretreatment with $CO_2$ Laser (Ultra Dream Pluse); c) without any pretreatment. All prepared surfaces were bonded with Single Bond 2 and built up with resin composite (Filtek Z250). The micro-tensile bond test was performed. Fracture modes were evaluated by stereomicroscopy. Pretreated surfaces and bonded interfaces were characterized by scanning electron microscope (SEM). The data obtained was analyzed by two-way ANOVA (${\alpha}$=0.05). RESULTS. For both sound and eroded dentin, samples treated with desensitizer showed the greatest ${\mu}TBS$, followed by samples without any treatment. And samples treated with $CO_2$ laser showed the lowest ${\mu}TBS$. SEM study indicated that teeth with eroded dentin appeared prone to debonding, as demonstrated by existence of large gaps between adhesive layers and dentin. CONCLUSION. Pretreatment with Gluma increased the ${\mu}TBS$ of Single Bond 2 for eroded and sound teeth. $CO_2$ laser irradiation weakened bond performance for sound teeth but had no effect on eroded teeth.