• Journal of the Korea Concrete Institute
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• v.20 no.5
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• pp.557-563
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• 2008

Recently, the amount of disposed construction materials like demolished concrete is growing fast and the shortage of natural concrete aggregate is becoming serious. Therefore, recycling of aggregate extracted from the demolished concrete is getting important and use of the recycled aggregate for concrete has been seriously considered. However, the use of the recycled aggregate even for low performance concrete is very limited because recycled aggregate which contains large amount of old mortar has very low quality. Therefore, removing the paste sticked to the recycled aggregate is very important in the manufacturing of high quality recycled aggregate. We have studied a series of research according to complex crushing method, which is removed the ingredient of cement paste from recycled fine aggregate using both the low speed wet abrasion crusher as mechanical process and the acid treatment as chemical processes. This paper is to analyze the quality of the recycled fine aggregate produced by those complex method and investigate optimum manufacturing condition for recycled fine aggregate by the design of experiments. The experimental parameters considered are water ratio, coase aggregate ratio, and abrasion time. As a result, data concerning the properties of recycled sand were obtained. It was found that high quality recycled fine aggregate could be to obtain at the condition of the fifteen minute of abrasion-crusher time and the over 1.0 of recycled coarse aggregate ratio.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.202.2-203
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• 2003

전통주의 계승발전을 위해 전통주의 개선과 재현의 필요성이 높아짐에 따라 지난날 맛 좋았던 우리의 전통주의 연구와 개발이 활발히 진행되고 있다. 또한 최근 미곡의 과잉생산으로 인한 과잉쌀 생산에 대한 수요체 창출을 위한 쌀가공품의 개발이 매우 시급한 실정이다. 최근 알콜농도가 낮은 술을 선호하는 경향과 전통주의 특수한 풍미로 인하여 현재 전통주는 많은 사람들로부터 각광을 받고 있어서 현재 몇몇 지역에서 민속주와 토속주가 허가되어 시판되고 있다. 진양주는 전남 해남지역의 전통민속주로서 해남지역에서 생산되는 찹쌀을 원료로 하여 상온에서 발효시키는 독특한 방법으로 제조되는데 이 진양주는 발효과정에서 외부환경의 영향을 많이 받게 된다. 그중 외부온도는 진양주의 품질에 직접적인 영향을 미치게 되는데 아직까지는 진양주제조과정에서 최적발효온도에 대한 연구는 보고된 것이 없다. 본 연구에서는 발효온도를 2$0^{\circ}C$와 $25^{\circ}C$로 하였을 때 발효과정에서 술의 품온, pH, 당도, 알콜함량, 총산의 변화를 조사하였으며 관능검사를 통하여 종합적인 기호도를 평가하여 최적의 발효온도를 탐색하고자 했다. 발효과정에서 술의 품온은 온도계를 사용하여 측정하였고 pH는 pH-meter로 측정하였으며 당도는 당도계를 이용하여 측정하였다. 알콜함량과 총산은 국세청의 주류분석규정에 따라 증류법과 중화적정법을 사용하여 측정하였다. 관능검사는 식품공학과 대학원생과 학부생 10명을 대상으로 종합적인 기호도에 대하여 5단계 평점법으로 실시하였다. 2$0^{\circ}C$에서 발효시 품온은 20.2~23.8$^{\circ}C$사이에서, $25^{\circ}C$에서 발효시 품온은 25.2$^{\circ}C$~28.2$^{\circ}C$사이에서 변화되었고 pH는 2$0^{\circ}C$ 발효시 3.47~4.62 사이에서, $25^{\circ}C$ 발효시 pH는 3.28~4.65사이에서 변화되었고 최종 pH는 2$0^{\circ}C$에서 발효시 3.71로써 $25^{\circ}C$ 발효시 3.58보다 높았다. 최종당도는 2$0^{\circ}C$, $25^{\circ}C$ 발효시 각각 10.2。Brix와 8.4。Brix 였고 알콜농도는 2$0^{\circ}C$발효시 13.8%로 $25^{\circ}C$ 발효시 14.8% 낮았으며 총산은 2$0^{\circ}C$ 발효시 1.32%로 $25^{\circ}C$ 발효시 1.62%보다 낮게 나타났다. 관능검사를 통한 종합적인 기호도는 2$0^{\circ}C$에서 발효시킨 진양주가 4.2로써 $25^{\circ}C$에 발효시킨 진양주 3.5보다 높은 것으로 나타났다. 관능검사시 $25^{\circ}C$에서 발효한 진양주는 신맛이 많이 난다는 결과로 볼 때 최종 pH가 3.58로 낮고 총산이 1.62%로 높아서 나온 결과라고 생각된다. 결론적으로 진양주를 제조할 시 발효온도는 2$0^{\circ}C$가 발효온도 $25^{\circ}C$보다 더 적합하다고 생각된다.

• Resources Recycling
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• v.8 no.4
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• pp.45-56
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• 1999

The purpose of tlus sludy was to preparc raw material powder for Mn-Zn iclrile, h m mined mill scale and fero-Mn, usins a co-spray roasting process The mill scale and ferra-Mn uscd in this raalins process was rcf~nedb y mesn-ns of a slxc~apl rxcss ~nvolvinm~a te~ialsc ontalning imp~u-ltleso r less than 100 pprn In this study an effeclive spray roaster system. wllich produces fme complex oxide powder, collects produccd ~owder.,m d prcvel~tse ~~llssiooifi HCI gas. was also manufactured. By means of spray~ngp urifcd raw malerial solu~lionl nln a manufacued high tcmpervture rumace. &-ferrite powder and a comnpleu o ~ d e powder of Fe,O; and M,x203 were manufactured. The chmcterlstics of the composllion. surface urca, and p'miicle size dismbulion or the produced powder were exmined. ptoduced powdcr was then ~ m e dwi tli ZnO powder. aid olher addilives of defined cornposnion, and Mn-Zn femite cares werc praiuccil by meuns of Sorlning and closely controlled sintering processes. The magpelic p~oprlieso f c olo~ss, initlal permeability. mauin~u~mnn agnehc flux. coz~civcr orcc and residual magnccic flux for the above cores we,= measured, and fmm Il~ase I-csulls the eflicacy of lhe co-spray roasling pncess to pl.ellare raw material powder lor Mn-Zn ferntc was established

• Resources Recycling
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• v.22 no.3
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• pp.91-99
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• 2013

Steel industry which has been accomplishes the base of our country economy, automobile and electronic industry are taking charge of the role, whose electroplating is important. Large amount of wastewater and various metal salts, including hazardous materials was generated from the electroplating pre-treatment, plating, washing and post-plating. Currently, the general wastewater follows in the environmental law and neutralization after controlling, sludge where the various metal is mixed reclaims below multiple regulative and trust it is controlling. The sludge which includes the gas price metal reclaims in the field and trust it controls. a reclamation price of land it is insufficient but and the control expense holds plentifully and it loses the gas price metal which is valuable. Consequently, The research regarding to recover a gas price metal actively from this waste water, it is advanced. A new method to recover valuable metals from electroplating wastewater synthesis of metal sulfides using topical methods utilizing iron oxidizing bacteria, reagent of sulfides and solvent extraction using an organic solvent, such as the development of the law to recover these metals and metal sulfides of wastewater using selective recovery have been studied. By using these wastewater treatment method under frequency above 95%, it has been obtained the valuable metal from the wastewater, where the metal ion of Fe, Cu, Zn and Ni complexes was mixed. As we discuss the wastewater, which has been discharged from electroplating process, it is important and will be applied to the resources of metal in the urban mine.

• Polymer(Korea)
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• v.35 no.4
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• pp.363-369
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• 2011

To study the effect of incorporation of a surface crosslinking layer on a crosslinked poly (sodium acrylate) (cPSA) absorbent with ethylene glycol dimethacrylate CEGDMA), we synthesized several surface crosslinked cPSAs with EGDMA by an inverse emulsion polymerization method to delay the absorption of excess water in concrete, Liquid paraffin was used as a continuous phase. cPSA was synthesized with acrylic acid (AA) neutralized with aqueous 8 M sodium hydroxide solution as a monomer, N,N-methylene bisacrylamide (MBA) as crosslinking agent and ammonium persulfate (APS) and sodium metabisulfite (SMBS) as a redox initiator system by inverse emulsion polymerization. FTIR spectroscopy was used to characterize $Ca^{2+}$ ion interaction with cPSA and cPSA-EGDMAs. The swelling ratios of synthesized absorbents were evaluated from the absorption in deionized water, cement saturated aqueous solution and aqueous solution of calcium hydroxide (pH 12). Equilibrium swelling times for cPSA and surface crosslinked cPSA with EGDMA were 2 and 3 hrs, respectively. We also observed an increase in setting time of the cement and an increase in the compressive strength of mortar by addition of the synthesized cPSA-EGDMA.

• Korean Journal of Veterinary Service
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• v.22 no.4
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• pp.363-370
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• 1999

Isolation of PRRSV was attempted from 646 swine sera collected from swine farms. The MARC-145 cell, which is highly permissive to PRRSV, was used for virus isolation, propagation, IFA test, and VN test. Total 36 cytopathic viruses to MARC-145 cells were isolated. The virus isolates were identified as a PRRSV by the IFA test and VN test using the reference sera prepared by experimental infection of reference PRRSV CNV-1 into 30 day-old pig. In addition to serological conformation, ORF5 of genomic RNA of 6 selected cytopathic viruses were amplified by the RT-PCR. The resulting PCR products were examined by electrophoresis in 1.2% agarose gel. An appropriate bands of about 680bp including the flanking sequence of total 80bp were seen on agarose gel.

• Membrane Journal
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• v.4 no.1
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• pp.38-45
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• 1994

The experiment was conducted to evaluate the effects of variables in preparing TFC membrane by interfacial polymerization. Obtained results are as follow: As the concentration of MPD increses, the rejection rate incresed, the total volume flux was decresed. As the dipping time in MPD solution increases, the rejection rate increased, the total volume flux was increased until reach optimum point. As the dipping time in TMC solution increses, the total volume flux increased, the rejection rate was increased until reach optimum point. As the curing temperature increases, the total volume flux increased was an optimum point in the rejection rate. Since the quantity of generating hydrochloric acid was small, the required quantity of NaOH for neutriliztion was small. The post-treatment with ethanol, isopropanol and water in the temprerature ranging of $5~7^{\circ}C$ brought an increment of the rejection and the total volume flux, For water temperature ranging of $5~7^{\circ}C$was the optimum temperature in the post treatment.

• Korean Journal of Poultry Science
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• v.15 no.3
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• pp.199-206
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• 1988

A total of 3 hybridoma clones producing monoclonal antibody (MCA) against infectious laryngotracheitis virus (ILTV) was established by somatic cell hybridization between mouse myeloma cells and spleen, cells from mice immunized with ILTV. The MCAs were screened by the indirect flourescent antibody (IFA) staining and the specific hybridomas were cloned by limiting dilution method. The MCAs produced by the 3 hybriomas were all classified as immunogloblin G and found to be reacting against common antigen(s) of high and low pathogenic ILTV examined. The titer of these antibodies in mouse ascitic fluid was from $10^5$ to $10^6$. Indirect fluorescent antibody test using these antibodies was found to be quite effective for the detection of ILTV from infected chickens being the most sensitive among the test methods adopted.

• Microbiology and Biotechnology Letters
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• v.25 no.6
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• pp.623-629
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• 1997

The studies of isolation and physiological characteristics of mesophilic or thermophilic bacteria from thermophilic oxic process (TOP) treating Chinese restaurant wastes were conducted. Chinese restaurant wastes were consist of moisture; 75.8%, solids; 24.2% and ash; 0.49%. The volatile solid was about 99% of total dry solids. In wastes used in this experiment, there was content of crude protein; 4.47%, crude lipid; 3.56%, free sugar, 0.4% , crude starch; 10.34% and crude fiber 3.14%, respectively. And then it has about 4,970 kcal/kg-dry solid of Chinese restaurant wastes. From TOP treating the chinese restaurant wastes, 37 strains of mesophilic or thermophilic bacteria were primarily isolated using medium used for the isolation and among them 6 strains of thermophilic and 7 strains of mesophilic bacteria were selected by testing the activities of amylase, cellulase, protease and lipase. TB-1, TB-9 as thermophilic bacteria and MB-15-1, 15-2, MB23 as mesophilic bacteria having strong enzyme activity were selected among isolated strains. All selected strains reduced nitrate to nitrite and they utilized glucose, manose, manitol, and maltose as carbon source. From these MB15-2 was identified as Bacillus cereus, TB1, Bacillus licheniformis and TB9; Bacillus schlegelii.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.11
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• pp.596-602
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• 2016

Potassium iodide (KI) TRO sensor for measuring total residual oxidant which is an index for disinfection and neutralization in ballast water has been constructed. The results of UV absorption wavelength and absorbance test in various TRO concentrations show high linear correlation ($r^2=0.9825$) at 350 nm wavelengths and it can be possible to visualize numerical value of TRO concentration (0.1~7.0 mg/L). The result of comparison test according to TRO concentration between the KI based TRO sensor system and the DPD based TRO sensor system showed identical trend. Overall results indicated that the KI TRO sensing system could be applied for continuous TRO concentration measurement in ballast water treatment system.