• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.503-508
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• 2007

Small scale D-water treatment plant(WTP) where has slow sand filtration was using raw water containing high concentration of manganese (> 2mg/l). The raw water was pre-chlorinated for oxidation of manganese and resulted in difficulty for filtration. Thus, sometimes manganese concentration and turbidity were over the water quality standard. Two stage rapid manganese sand filtration pilot plant which can treat $200m^3/d$ was operated to solve manganese problem in D-WTP. The removal rate of manganese and turbidity were about 38% and 84%, respectively without pH control of raw water. However, when pH of raw water was controlled to average 7.9 with NaOH solution, the removal rate of manganese and turbidity increased to 95.0% and 95.5%, respectively and the water quality of filtrate satisfied the water quality standard. Manganese content in sand was over 0.3mg/g which is Japan Water Association Guideline. The content in upper filter was 5~10 times more than that of middle and lower during an early operation but the content in middle and lower filter was increased more and more with increase of operation time. This result means that the oxidized manganese was adsorbed well in sand. Rapid manganese sand filter was backwashed periodically. The water quality of backwash wastewater was improved by sedimentation. Thus, turbidity and manganese concentration decreased from 29.4NTU to 3.09NTU and from 1.7mg/L to 0.26mg/L, respectively for one day. In Jar test of backwash wastewater with PAC(Poly-aluminum chloride), optimum dosage was 30mg/L. Because the turbidity of filtrate was high as 0.76NTU for early 5 minute after backwash, filter-to-waste should be used after backwash to prevent poor quality water.

• Journal of Acupuncture Research
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• v.28 no.1
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• pp.1-14
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• 2011

목적 : 인진약침이 고지방식이로 유발된 비만 ICR mice에서 비만 및 동반 대사이상에 미치는 효과와 그 기전을 연구하고자 한다. 방법 : 인진약침의 비만 예방효과를 검증하기 위하여, 4주간 고지방식이를 급여하면서 150mg/kg 또는 300mg/kg의 인진약침을 양측 비수($BL_{20}$)에 교대로 매일 피하에 시술하였다. 또한 인진약침의 비만 치료효과를 검증하기 위하여, 4주간 고지방식이를 급여한 비만 ICR mice에 추가 4주간 고지방식이를 유지하면서 300 mg/kg 인진약침액과 vehicle control로써 등량의 distilled water를 양측 비수($BL_{20}$)에 교대로 매일 피하에 약침시술하였다. 인진약침의 항비만효과와 기전을 알아보기 위해, 체중, blood glucose, insulin, total cholesterol, triglyceride, non-esterified fatty acid (NEFA), AST, ALT levels 등 대사지표를 측정하고 부고환조직의 조직학적 관찰을 시행하였으며, AMPK activation과 adipocyte differentiation, fatty acid ${\beta}$-oxidation 및 thermogenesis와 관련된 gene expressions을 평가하였다. 결과 : 인진약침의 치료를 통하여 고지방식이 급여로 인한 체중의 증가가 억제되었을 뿐만 아니라, 비만 ICR mice의 체중을 감소시켰으며, glucose 및 lipid homeostasis를 개선시켰으며 지방조직의 증식을 억제하였다. AMPK의 phosphorylation과 CPT-1 및 UCP2의 발현을 증가시켰으며, PPAR-${\gamma}$, C/EBP${\alpha}$, aP2, LPL,FAS, SCD-1의 발현을 억제하였다. 결론 : 인진약침은 고지방식이 유도 동물모델에서 비만 및 동반 대사이상을 개선시키는 효과가 있으며, 이는 식이억제에 의한 2차적 효과라기 보다는 energy expenditure를 증가시키고, pre-adipocyte differentiation 및 proliferation을 억제하며, lipogenesis를 억제하고 lipolysis를 증가시키는 효과에 의한 것으로 사료된다.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.100-105
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• 2003

25Cr-20Ni series strainless steel have an excellent high temperature strength, high oxidation and high corrosion resistance. However, further improvement can be creep strength by work hardening prior creep. In the present study, the effect of prestraining at room temperature on the creep behavior of a Class M(STS310S) and a Class A(STS310J1TB) alloy containing precipitates have been examined. Prestraining was carried out at room temperature and range of prestrain was $0.5{\sim}2.5$ % at STS310J1TB and $2.0{\sim}7.0$ % at STS310S. Creep behavior and creep rate of pre-strained specimens were compared with that of virgin specimens. Room temperature prestraining produced the creep life that is longer than that of a virgin specimen both for STS310J1TB and STS310S when creep test carried out at the temperature lower than recrystallization temperature. The reason for this improvement of creep life was ascribable to the interaction between dislocations and precipitates in addition to the dislocation-dislocation interaction in STS310J1TB and the dislocation-dislocation interaction in STS310S. The beneficial effect of prestraining in STS310J1TB was larger than that of STS310S.

• Applied Chemistry for Engineering
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• v.17 no.4
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• pp.409-413
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• 2006

An experimental study on a combined $De-NO_x$ process of non-thermal plasma and $NH_{3}$ SCR, which can be operated under low temperature conditions, i.e. $150{\sim}200^{\circ}C$, has been conducted. The test results confirmed feasibility of fast SCR reaction, which shows faster reactivity compared with typical SCR reaction under the low temperature conditions. The test showed that pre-oxidation step to convert NO to $NO_2$ is necessary for the fast SCR reaction, and the appropriate ratio of $NO_{2}/NO_{x}$ ranges from 0.3 to 0.5. Ammonium salts produced under low temperature conditions, effects of hydrocarbons on the combined process, the operation power of the process are discussed in the present study.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.5
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• pp.831-836
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• 2010

In addition to spice, black pepper (Piper nigrum Linne : PnL) has been used as herbal medicine because of its function in anti-oxidation, anti-inflammation, and anti-carcinogenesis. Recently, it has been reported that piperine, a component of PnL, inhibits adipocyte differentiation by repressing various adipogenic gene expressions. In this study, we determined whether piperine is a major constituent of PnL that confers the anti-adipogenic activity at whole genome level. Differentiation of 3T3-L1 pre-adipocytes was induced in presence of PnL extract or piperine. To compare genes that are regulated by PnL extract or piperine, we performed expression profiling using microarrays (Agilent Mouse 44k 4plex). RNA samples were labeled with Cy3 and Cy5, respectively. Labeled samples were hybridized to the microarrays. Results were filtered and cut off set p<0.05. Genes exhibiting significant differences in expression level were classified into Gene Ontology (GO)-based functional categories (http://www.geneontology.org) and KEGG (http://www.genome.jp/kegg/). Extract of PnL and its component piperine reduced lipid accumulation in 3T3-L1 cells during adipogenesis. Such anti-adipogenic activity appears to result from down-regulation of transcription factor genes involved in adipogenesis, and other genes involved in fatty acid synthesis, transport, triglyceride synthesis, and carbohydrate metabolism. These genome-wide studies lead to conclude that piperine, as a critical component of PnL, plays common role with PnL in anti-adipogenesis.

• Journal of Environmental Science International
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• v.20 no.7
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• pp.907-917
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• 2011

This study investigated the application of experimental design methodology to optimization of conditions of air-plasma and oxygen-plasma oxidation of N, N-Dimethyl-4-nitrosoaniline (RNO). The reactions of RNO degradation were described as a function of the parameters of voltage ($X_1$), gas flow rate ($X_2$) and initial RNO concentration ($X_3$) and modeled by the use of the central composite design. In pre-test, RNO degradation of the oxygen-plasma was higher than that of the air-plasma though low voltage and gas flow rate. The application of response surface methodology (RSM) yielded the following regression equation, which is an empirical relationship between the RNO removal efficiency and test variables in a coded unit: RNO removal efficiency (%) = $86.06\;+\;5.00X_1\;+\;14.19X_2\;-\;8.08X_3\;+\;3.63X_1X_2\;-\;7.66X_2^2$ (air-plasma); RNO removal efficiency (%) = $88.06\;+\;4.18X_1\;+\;2.25X_2\;-\;4.91X_3\;+\;2.35X_1X_3\;+\;2.66X_1^2\;+\;1.72X_3^2$ (oxygen-plasma). In analysis of the main effect, air flow rate and initial RNO concentration were most important factor on RNO degradation in air-plasma and oxygen-plasma, respectively. Optimized conditions under specified range were obtained for the highest desirability at voltage 152.37 V, 135.49 V voltage and 5.79 L/min, 2.82 L/min gas flow rate and 25.65 mg/L, 34.94 mg/L initial RNO concentration for air-plasma and oxygen-plasma, respectively.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.129-133
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• 1998

The white-rot fungi Phanerochaete chrysosporium ATCC 24725, Pleurotus ostreatus ATCC 32783, Lentinus edodes ATCC 24462, and Trametes versicolor ATCC 42530 were studied for their ability to degrade lignin, phenanthrene, and anthracene. Lignin in rice-straw was degraded by 14.4, 28.73, and 33.88% by P. chrysosporium, T. versicolor, and P. ostreatus, respectively. Approximately 12% and 83% of phenanthrene was degraded in 1 and 5 days, respectively, when the pre-grown mycelIium matrix of P. ostreatus. was incubated with 10 ppm of phenanthrene in modified Kirk's medium (nitrogen limited) at $25^{\circ}C$. Approximately 2%> and 61% of phenanthrene was degraded when the phenanthrene concentration was increased to 30 ppm. Similar trends were observed with phenanthrene using P. chrysosporium. Mycelial growth of T. versicolor was less inhibited at 30 ppm phenanthrene than for P. ostreatus and P. chrysosporium. Better degradation of phenanthrene by T. versicolor may be attributed to better mycelium growth. One hundred percent of 15 ppm anthracene was degraded in 10 days by both P. chrysosporium and T. versicolor. 40 ppm anthracene inhibited the mycelial growth of P. chrysosporium. lignin peroxidase activity, which was previously reported to be involved in initial phenanthrene oxidation, was also detected from the culture broth of the strains tested. The rates of lignin peroxidase production in the cultures were not consistent with the rate of PAH hydrolysis during incubation.

• Environmental Engineering Research
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• v.23 no.2
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• pp.210-215
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• 2018

Coal seam gas (CSG) water, to be discharged, has been usually treated in reverse osmosis (RO) plants which require extensive and expensive pre-treatment. However, current low gas prices have been a great driver for relevant industries to seek for alternative cost-effective technologies in the aspect of its beneficial use and fit-for-purpose usable water production. In this paper, a combined system with a two-stage pore control fiber (PCF) filtration and a RO system was designed and tested for CSG water treatment. Also, a coagulation reactor was placed in front of the PCF to further enhance suspended solid removal. More than 99% of SS were removed through the PCF filtration while organic, total nitrogen and total phosphorous were mostly removed by the RO system. Especially along with a decrease in conductivity, the total dissolved solid derived from salts was mainly removed in the RO system. Having $OH^-$ undetected, $HCO_3{^-}$ was found to be a dominant compound and its removal efficiency was 97-98% after the RO treatment. And a Fe(III) type of Polytetsu, which was the first to be tested in this paper, was found to be a better option than a Al(III) type of Poly Aluminium Chloride due to its greater coagulation efficiency and applicability at a broader range of pH than the Al(III) type. In addition, there was no noticeable change in oxidation reduction potential, suggesting that an additional process is required to oxidize non-ionic organic carbons (detected as total organic carbon).

• Journal of Powder Materials
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• v.9 no.6
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• pp.441-448
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• 2002

Dispersions of non-soluble ceramic particles in a metallic matrix can enhance the strength and heat resistance of materials. With the advent of mechanical alloying it became possible to put the theoretical concept into practice by incorporating very fine particles in a flirty uniform distribution into often oxidation- and corrosion- resistant metal matrices. e.g. superalloys. The present paper will give an overview about the mechanical alloying technique as a dry, high energy ball milling process for producing composite metal powders with a fine controlled microstructure. The common way is milling of a mixture of metallic and nonmetallic powders (e.g. oxides. carbides, nitrides, borides) in a high energy ball mill. The heavy mechanical deformation during milling causes also fracture of the ceramic particles to be distributed homogeneously by further milling. The mechanisms of the process are described. To obtain a homogeneous distribution of nano-sized dispersoids in a more ductile matrix (e.g. aluminium-or copper based alloys) a reaction milling is suitable. Dispersoid can be formed in a solid state reaction by introducing materials that react with the matrix either during milling or during a subsequent heat treatment. The pre-conditions for obtaining high quality materials, which require a homogeneous distribution of small dis-persoids, are: milling behaviour of the ductile phase (Al, Cu) will be improved by the additives (e.g. graphite), homogeneous introduction of the additives into the granules is possible and the additive reacts with the matrix or an alloying element to form hard particles that are inert with respect to the matrix also at elevated temperatures. The mechanism of the in-situ formation of dispersoids is described using copper-based alloys as an example. A comparison between the in-situ formation of dispersoids (TiC) in the copper matrix and the milling of Cu-TiC mixtures is given with respect to the microstructure and properties, obtained.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.511-520
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• 2016

The most energy-demanding step of wastewater treatment is the aeration-dependent elimination of organic carbon. Microbial fuel cells (MFCs) offer an alternative strategy in which carbon elimination is conducted by anaerobic microorganisms that transport respiratory electrons originating from carbon oxidation to an anode. Hence, chemical energy is directly transformed into electrical energy. In this study, the use and stability of barcode-containing exoelectrogenic model biofilms under non-axenic wastewater treatment conditions are described. Genomic barcodes were integrated in Shewanella oneidensis, Geobacter sulfurreducens, and G. metallireducens. These barcodes are unique for each strain and allow distinction between those cells and naturally occurring wild types as well as quantification of the amount of cells in a biofilm via multiplex qPCR. MFCs were pre-incubated with these three strains, and after 6 days the anodes were transferred into MFCs containing synthetic wastewater with 1% wastewater sludge. Over time, the system stabilized and the coulomb efficiency was constant. Overall, the initial synthetic biofilm community represented half of the anodic population at the end of the experimental timeline. The part of the community that contained a barcode was dominated by G. sulfurreducens cells (61.5%), while S. oneidensis and G. metallireducens cells comprised 10.5% and 17.9%, respectively. To the best of our knowledge, this is the first study to describe the stability of a synthetic exoelectrogenic consortium under non-axenic conditions. The observed stability offers new possibilities for the application of synthetic biofilms and synthetically engineered organisms fed with non-sterile waste streams.