• Journal of Korean Society of Environmental Engineers
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• v.36 no.7
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• pp.492-497
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• 2014

This study investigated removal characteristics of organic matters in pretreatment and reverse osmosis (RO) membrane processes for seawater desalination. Also, the influence of the changes in characteristics of organic matters on the membrane fouling was assessed. The pretreatment processes included dual media filtration (DMF), pressurized membrane filtration (MF), and submerged membrane filtration (SMF). Turbidity, UV absorption at 254 nm, dissolved organic carbon, size exclusion chromatography (SEC), fluorescence excitation emission matrix (FEEM), and transparent exopolymer particles (TEP) in raw and processed waters were analyzed. Ions and minerals were not removed by any pretreatment process tested, but were removed over 99% through the RO membrane process. Hydrophobic organics, which can play major role in organic membrane fouling, were relatively readily removed compared with hydrophilic ones. Membrane based pretreatment such as MF and SMF exhibited better removals of organics than conventional DMF. As the levels of organics in pretreated water decreased, the silt density index (SDI) decreased. MF treated water exhibited the lowest SDI value; this is possibly due to the lowest TEP ($0.1-0.4{\mu}m$) concentrations.

• Journal of Environmental Health Sciences
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• v.16 no.1
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• pp.67-74
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• 1990

An effect of carbon tetrachloride (CCl$_{4}$) was studied on the xanthine oxidase(XOD)activity of small intestine in male rats. Concomitantly a cause of increasing small intestine XOD was focused on an effect of actinomycin D and the kinetics of partial purified XOD frdm small intestine in CCl$_{4}$ intoxicated rats. An injection of CCl$_{4}$ to the rats showed an increase of small intestine XOD. In the pretreatment of actinomycin D before injection of CCl$_{4}$ to the rats, the XOD activities of small intestine were significantly decreased. In the partial purified enzyme preparation, the small intestine XOD in CCl$_{4}$ intoxicated rats showed the more increased Km and Vmax value with xanthine as substrate than that of control group.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.674-677
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• 2002

Vertically aligned CNTs were grown on Fe-deposited $SiO_2$ substrates using thermal CVD of acetylene gas. The size of Fe particle is controlled by the flow rate of $NH_3$ and pretreatment time, which leads to control the diameter of CNTs. As the diameter of CNTs decreases, the growth rate is enhanced with an inverse dependence of the CNT diameter. The growth rate of CNTs increases linearly as the growth time increases until 30 min but is rapidly decreased over 40 min. We found an inverse relation between the diameter and growth rate of carbon nanotubes. As the diameter of CNTs increases, the compartment layers of bamboo-shaped CNTs appear more frequently. A base-growth model is suitable to explain the dependence of growth rate and structure of CNTs on the diameter size of catalytic particles.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.05a
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• pp.82-87
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• 1995

Carbon dioxide fixation by microalgae has several advantages such as no requirements for the pretreatment over phycal and/or chemical $CO_2$ fixation processes. Chlorella sp. HA-1, fresh algae. and Chlorococcum littorale. marine algae, were used to do $CO_2$ fixation work. The experimental parameters were light intensity and $CO_2$ concentration. Chlorella sp. HA-1 has the maximum growth rate at 8 Klux and 10% $CO_2$ concentration. Chlorococcum littorale showed the maximum growth at similar conditions. The results indicated the feasibility of the Chlorella HA-1 and Chlorococcum littorale for mass cultivation using flue gas.

• Carbon letters
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• v.8 no.1
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• pp.1-5
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• 2007

The use of low cost and ecofriendly adsorbent has been investigated as an alternative to the current expensive method of removing dyes from wastewater. Cow dung cakes were collected from the nearby village which was burnt in a muffle furnace at $500^{\circ}C$ to obtain the required ash. This paper deals with the removal of Reactive Blue 221, Acidoll Yellow 2GNL and Olive BGL which are mainly used in textile industry, from aqueous solution by cow dung ash without any pretreatment. The adsorption was achieved under different pH, adsorbate concentration and the applicability of Langmuir and Freundlich isotherms were examined.

• Journal of Environmental Science International
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• v.17 no.12
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• pp.1307-1314
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• 2008

Hydrogen gas is used as a fuel for the proton exchange membrane fuel cell (PEMFC). Trace amount of carbon monoxide present in the reformate $H_2$ gas can poison the anode of the PEMFC. Therefore, preferential oxidation (PROX) of CO is essential for reducing the concentration of CO from a hydrogen-rich reformate gas. In this study, conventional Pt/$Al_2O_3$ catalyst was prepared for the preferential oxidation of CO. The effects of catalyst preparation method, additive, and hydrogen on the performances of PROX reaction of CO were investigated. Water treatment and addition of Ce enhanced catalytic activity of the Pt/$Al_2O_3$ catalyst at low temperature below $100^{\circ}C$.

• Carbon letters
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• v.9 no.1
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• pp.1-7
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• 2008

The ability of cow dung ash without any pretreatment to remove color from textile dyes N Blue RGB, Green B and EOSIN YWS from aqueous solution has been investigated in this work. Cow dung ash, an ecofriendly and low cost adsorbent was prepared by burning cow dung cakes in the muffle furnace at $500^{\circ}C$. The adsorption was achieved under different pH and adsorbate concentration. The data was fitted to simple polynomial and the isotherms similar to Langmuir and Freundlich isotherms.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.1
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• pp.82-92
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• 2016

The reduction of carbon dioxide emission is hot issue in the world because we are confronted with serious global warming and climate change. As a part of carbon dioxide reduction efforts, various approaches for increasing filler loading have been carried out in order to decrease the energy consumption in papermaking processes. Effects of the pretreatment of GCC with cationic starch and MFC on the flocculation behaviour of GCC were investigated in this study. Pretreatment of GCC with cationic starch caused the change of electric charge of suspension and flocculation behaviour of GCC. Largest flocculation size was obtained near the isoelectric point in the case of cationic starch treatment. When MFC (30 times grinded) was added after preflocculation of GCC with cationic starch, the flocculation size was increased, but largest flocculation size was obtained at -150 mV of electric charge of suspension in this study. However the addition of highly grinded MFC (60 times grinded) caused smaller flocculation size of GCC than those of MFC (30 times grinded). When GCC and MFC were mixed first, and then cationic starch was added, the characteristics of MFC and the change of electric charge which could be brought by cationic starch did not affect the flocculation size of GCC at all. The flocculation size obtained by the combination of cationic starch and MFC was smaller than those of cationic starch. These results show that flocculation behaviour could be controlled by the change of electric charge of suspension and the combination methods of cationic starch and MFC.

• Toxicological Research
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• v.22 no.4
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• pp.333-338
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• 2006

This study was to investigate the preventive effects in anti-oxidation of Ulva lactuca extract fractions (ULEF) against $CCl_4$ toxification in liver total homogenate and mitochondrial fraction of ULEF-pretreated and carbon tetrachloride $(CCl_4)-posttreated$ rats. ULEF was intraperitoneally administered into rats at dose of 1 ml/kg for14 days. On the day 15, 3.3 ml/kg of $CCl_4$ dissolved in olive oil (1:1) was injected 12 hr before anesthetization. Activities of superoxide dismutase(SOD) in mitochondrial fraction were measured and catalase (CAT), glutathione peroxidase (GPx), malondialdehyde (MDA) in liver total homogenate. SOD, CAI and GPx were higher in the ULEF-pretreated and $CCl_4-posttreated$ group than those in the $CCl_4-posttreated$ group, and the pretreatment of ULEF decreased MDA. These results showed that the pretreatment of ULEF had the preventive role in the activities of anti-oxidative enzymes, SOD, CAT and GPx

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.4
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• pp.321-329
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• 2002

Clostridium butyricum, Lactobacillus amylophillus, Lactobacillus amylovorus, Lactobacillus acidophillus, AI-9 produced hydrogen and /or organic acids using glucose, lactose and starch at the anaerobic culture conditions. Cl. butyricum NCIB 9576 evolved 1,700 ml H2/L-culture broth and accumulated butyric acid, acetic acid, propionic acid and ethanol in its culture broth when lactose was used as a carbon source during 24 hrs of fermentation. L. amylovorus ATCC 33620 accumulated lactic and acetic acids and some reducing sugars when starch was used as a carbon source without hydrogen production. Instead of starch as a carbon source, L. amylovorus ATCC 33620 produced lactic acid from algal biomass during fermentation and the acid-heat or freeze-thaw pretreatment of algal biomass accelerate the lactic acid fermentation.