• 제목/요약/키워드: Agitation method and time

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딥핑 방식을 이용한 ITO 표면의 효율적인 포토레지스트 박리공정 (An Efficient Photoresist Stripping Process on the ITO Surface Using the Dipping Method)

  • 김준현;심재명;주기태;김용성;정병현
    • 한국생산제조학회지
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    • 제25권4호
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    • pp.281-289
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    • 2016
  • Agitation is a secondary process used to increase the PR stripping force on an ITO-glass surface; it is an efficient approach to stripping during production. It activates the stripper to chemically penetrate the PR layer and assists by breaking down the physical bonding forces at the surface. In this study, different stripping tests were conducted by varying the dipping time, the composition, the strip temperature, and the stripper concentration. Optimal PR strip conditions were estimated by using comparative visual inspection of stripped sample surfaces. The stripping process was affected by changes in the moving speeds and the sample positions. It was confirmed that the stripping capability improved at a dilute stripper ratio of 20-40% and a strip temperature of $30-40^{\circ}C$ and within 60 s of strip time.

청도읍성의 축성에 관한 연구 (A Study on the Construction of Cheongdo-Eupseong)

  • 김찬영
    • 대한건축학회논문집:계획계
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    • 제34권5호
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    • pp.119-127
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    • 2018
  • This study examined the construction method shown in literatures and materials discovered in rampart, barbican and guard platform for Cheongdo-Eupseong castle which was constructed immediately before Japanese Invasions of Korea (1592-98). According to the result of the examination, the construction method used in the coastal areas and inland areas of Gyeongsang province in the early Joseon period was applied to the rampart, barbican and guard platform in the east and north castle walls, which was constructed earlier than other parts of Cheongdo-Eupseong castle. However, from the western end of the northern castle wall, which was later constructed, to the western castle wall was rebuilt using a construction method different from the method applied to the parts that were constructed earlier after Japanese Invasions of Korea. Cheongdo-Eupseong castle was constructed on a flatland on a large scale and at a low height under unreasonable pressures to construct the castle in a short period of time for military defense as well as civil agitation in the imminent situation just before the outbreak of Japanese Invasions of Korea. In addition, various methods of constructing Eupseong castle utilized at that time were used together, and barbican and guard platform were built generally focusing on rapid completion and convenience, using other methods than the one mainly used at that time. This is the reason why there was a difference in the characteristics of the method and period of castle construction between Cheongdo-Eupseong castle and other Eupseong castles in the coastal areas and inland areas of Gyeongsang province.

Development of analytical method for potential diesel oxygenate using SPME technique combinded with GC-FID

  • 이규현;이시진;장순웅
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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    • pp.354-357
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    • 2004
  • The addition of oxygenates to diesel fuel can significantly reduce particulate emissions. Dibutyl maleate (DBM) and tripropylene glycol methyl ether (TGME) have been identified as possible additives based on their physicochemical characteristics and performance in engine test. However, their potential environmental impacts are unknown. therefore, practical considerations in the selection of an oxygenate additives should include cost, availability, compatibility with engines and fuel, and, particularly, its overall environmental impact. This study was investigated to determine optimal condition for the analysis of potential diesel oxygenates using SPME technique with GC-FID. Four fibers were compared and CAR/PDMS fiber was found to be the most sensitive when used direct-sampling. An absorption time of 30min and a desorption time of 5min provided to be the most sensitivity. The effects of experimental parameters such as the addition of salts, agitation, absorption time, compositon on the analysis were investigated. Analytical parameter such as linearity was also evaluated.

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초산(醋酸), 질산(窒酸), 인산(燐酸)을 함유한 삼원계(三元系) 폐혼산(廢混酸)으로부터 인산(燐酸) 회수(回收)에 관한 기초 연구(硏究) (A Study on the Recovery of Phosphoric acid from Waste acid containing Acetic acid, Nitric acid and phosphoric acid)

  • 이향숙;이창훈;신준영;김주엽;안재우
    • 자원리싸이클링
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    • 제14권5호
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    • pp.18-23
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    • 2005
  • 초산, 질산, 인산이 함유된 폐혼산으로부터 인산을 분리하여 재활용하기 위한 방법으로 용매추출법을 이용하였다. 폐혼산에서 초산과 질산을 선택적으로 분리하고, 추출 잔류액에서 인산을 회수하고자 하였다. 주요 실험 변수로는 추출제 농도, 교반시간, 교반속도 등의 변화에 따른 초산, 질산, 인산의 추출거동을 조사하였다. 또한, McCabe-Thiele diagram으로부터 초산, 질산 성분의 추출 및 탈거에 필요한 이론적 단수를 조사하였다. 실험결과 인산염계 추출제를 사용할 경우 초산과 질산을 선택적으로 분리 추출이 가능하였으며, 추출제의 함량은 유기상의 50%가 적합하였다. 교반속도와 교반시간의 영향은 크게 없었으며, 상비(A/O)=1/3, 6단에서 초산과 질산을 완전히 추출 분리하여 인산을 추출잔류액에서 회수가 가능하였다.

Optimization of Lipase Pretreatment Prior to Lipase Immobilization to Prevent Loss of Activity

  • Lee, Dong-Hwan;Kim, Jung-Mo;Shin, Hyun-Yong;Kim, Seung-Woo
    • Journal of Microbiology and Biotechnology
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    • 제17권4호
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    • pp.650-654
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    • 2007
  • In our previous work, a method of pretreating lipase was developed to prevent loss of its activity during covalent immobilization. In this study, Rhizopus oryzae lipase was pretreated before immobilization and then immobilized on a silica gel surface. The effects of the various materials and conditions used in the pretreatment stage on the activity of immobilized lipase were investigated. Immobilized lipase pretreated with 0.1% of soybean oil had better activity than those pretreated with other materials. The optimal temperature, agitation speed, and pretreating time for lipase pretreatment were determined to be $40^{\circ}C$, 200rpm, and 45min, respectively. The activity of immobilized soybean oil pretreated lipase was 630U/g matrix, which is 20 times higher than that of immobilized non-pretreated lipase. In addition, immobilized lipase activity was maintained at levels exceeding 90% of its original activity after 10 reuses.

노즐 분사 방식의 ITO 표면 포토레지스트 박리과정 요인의 수치해석 (Numerical Investigation of Factors affecting Photoresist Stripping Process on the ITO Surface using the Spray Method)

  • 김준현;이준혁;강태성;주기태;김용성;정병현;이대원
    • 한국생산제조학회지
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    • 제26권2호
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    • pp.158-165
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    • 2017
  • This study investigated spraying factors applicable to stripper usage. Cyclodextrine, as environment-friendly material, was included in the stripper composition. An efficient spray technology was applied for the Photoresist strip. For industrial applications, stripping requires a temperature below $50^{\circ}C$, a strip time within 50 s, and chemically stable activation. Spraying factors were organized considering many conditions-orifice diameter, working pressure (inlet speed), spray distance, and spray angle. For commercial practicability, the flow rate was limited to 3 L/min. The nozzle parameters were nozzle orifice diameter of 1.8-2.2 mm, spray distance of 40-60 mm, and injection speed of 0.7-1.2 m/s. Through the thermal spray movement of the fluid, the thermal boundary layer for a chemical reaction just above the ITO-glass surface and momentum region for sufficient agitation (above 4 m/s) was achieved.

Oil과 Modified Styrene을 사용(使用)한 미립(微粒) 무연탄(無煙炭)의 응집(凝集) (Agglomeration of fine anthracite using oil and modified styrene)

  • 이재장;장동성
    • 산업기술연구
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    • 제7권
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    • pp.27-47
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    • 1987
  • Fine anthracite is very difficult to upgrade by conventional processes such as gravity concentration or froth flotation, because large quantities of fine coals are generated at the mining and preparation stages and a significant portion of these fine coals are mixed with gangue minerals. This study, therefore, was carried out for the purpose of improving recovery of low ash clean coal, effective beneficiation of low-grade coking coal and removal of sulphur from high-sulphur coals by employing the method of selective agglomeration using oil or polystrene flocculants, for coals which are generally hydrophobic in nature will be extracted by using flocculants. Studies were performed by varying solid concentration, concetration of bridging liquid, mixing speed and mixing time, balling speed and balling time, dispersant dosage, flocculant dosage, pulp pH, and particle size. The results were : when the methods of the oil agglomeration and selective flocculation were employ(in the two process the sample was ground to the size of -74 micron), 1) ash content of the agglomerated coal was 9.85, 7.83%, 2) combustibel recovery of it was 98.5%, 93.5%, respectively. It was observed in selective flocculation that polystyrene is an effective flocculant for coal, De-entrapment of shale from the concentrate flocculated by mechanical agitation was necessary for substantional reductions in final ash content.

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Octadecyl-Modified Graphene as an Adsorbent for Hollow Fiber Liquid Phase Microextraction of Chlorophenols from Honey

  • Sun, Meng;Cui, Penglei;Ji, Shujing;Tang, Ranxiao;Wu, Qiuhua;Wang, Chun;Wang, Zhi
    • Bulletin of the Korean Chemical Society
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    • 제35권4호
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    • pp.1011-1015
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    • 2014
  • Octadecyl-modified graphene (graphene-C18) was fabricated and used as adsorbent in hollow fiber liquid phase microextraction (HF-LPME) for the first time. The extraction performance of graphene-C18 reinforced HF-LPME was evaluated using chlorophenols as model analytes. The factors affecting the extraction efficiency, such as extraction time, pH of the sample solution, agitation rate, the concentration of graphene-C18 and salt addition were optimized. After the graphene-C18 reinforced HF-LPME of the chlorophenols from honey sample, the analytes were separated and determined by high-performance liquid chromatography. The linearity was observed in the range of 5.0-200.0 ng $g^{-1}$ for 2-chlorophenol and 3-chlorophenol, and 2.0-200.0 ng $g^{-1}$ for 2,3-dichlorophenol and 3,4-dichlorophenol, respectively. The limits of detection (S/N = 3) of the method were lower than 1.5 ng $g^{-1}$. The recoveries of the method were between 88% and 108%. The method is simple, sensitive and has been resoundingly applied to analysis of chlorophenols in honey samples.

단백질 분해 효소가 세척에 미치는 영향 -효소와 오염 기질의 특성을 중심으로- (Influences of Protease on the Removal of Protein Soils from Cotton Fabrics -Emphasis on the Characteristics of Enzyme and Soil Substrates-)

  • 이정숙;심윤정
    • 한국의류학회지
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    • 제17권3호
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    • pp.491-505
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    • 1993
  • The influences of protease on the removal of various protein soils from cotton fabrics were studied. The human epidermal stratum corneum, hemoglobin and casein were used as protein soils. The soiled fabrics were denatured by steaming for 30 min. before washing and laundered using Terg-O-Tometer under washing conditions. The removal efficiency was evaluated by analysis of protein on the fabrics before and after washing by means of copper-Folin method. The relations between the removal and the characteristics of protease were discussed. Also the degradation of protein were examined by microscopy. The seperation of human epidermal stratum corneum after hydrolysis was examined by SDS-PAGE. The results obtained were as follow : 1. The protein from the soiled cotton fabric was removed effectively by adding protease. The removal of protein was increased in proportion to increasing of the enzyme concentration up to a certain point, but it began to decrease above the point. The removal effect was high in the order of casein>human epidermal stratum corneum>hemoglobin. Especially the protein was more effectively removed in ADS solution(pH 9.5) containing enzyme. 2. When protease was used with ADS. the removal of protein was efficiently showed in relatively short time(5~15min.) compared to using ADS only. It is due to the properties of this enzyme that reacts with very short time. 3. Even at low temperature the removal efficiency of enzyme was relatively higher compared with the activity of enzyme. The removal of protein soil was increased up to a maximum near $50^{\circ}C$, and then decreased. 4. The removal of protein by protease was improved with the increase of alkalinity in the pH range from 9.5 to 11.0 but it began to decrease above pH 11.0. 5. According to the increase of mechanical agitation, the removal effect was increased. But the removal efficiency of protease was more effective compared with the agitation in detergency. 6. According to the SDS-PAGE separation and micrograph it was confirmed that the human epidermal corneum was effectively hydrolysed by the enzyme added. So the fragments of protein were removed more efficiently by means of the interfacial reaction of AOS.

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The Effect of Weight-support Treadmill Training on the Balance and Activity of Daily Living of Children with Spastic Diplegia

  • Choi, Hyun-Jin;Nam, Ki-Won
    • The Journal of Korean Physical Therapy
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    • 제24권6호
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    • pp.398-404
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    • 2012
  • Purpose: This is designed to study the effect of weight-support walking training through motor learning on motor functions of children with cerebral palsy, in particular their activity of daily living and balance. Methods: Thirteen children with spastic cerebral palsy, at gross motor function classification system (GMFCS) levels III~IV, underwent treadmill walking training. It used principles of weight support, 4 times a week for 7 weeks, 10 minutes at a time, before and after neurodevelopmental physical therapy. Everyday functions were measured using Functional Independence Measure for Children (Wee-FIM). The ability to keep their balance was measured using electronic measuring equipment from good balance system and the assessment was made before and after the experiment. Results: There were significant differences (p<0.05) between pre and post experiment levels of functional independence in everyday life, in self-care activities, mobility, locomotion and social cognition. With regard to changes in standing balance, there were significant differences before and after the experiment (p<0.05) in GMFCS level III. There was a reduction in the agitation velocity in the x- and y-axes which measures the left-to-right shaking; in GMFCS level IV, velocity moment was reduced. Conclusion: Walking training using a treadmill can help improve the everyday activity and balance in children with spastic cerebral palsy. It can also be served as a useful purpose as a method of intervention in pediatric care.