방화지구 내 인접 건물 연소 확대 방지를 위한 드렌처설비 개선방안에 관한 연구

문철환 부경대학교 2018 국내석사

본 연구에서는 방화지구 내 드렌처설비의 불명확한 기준 등으로 소방종사자들의 업무 혼선이 초래되고 있어 이에 따른 대책으로 드렌처설비 현장설치 사례조사와 소방종사자를 대상으로 한 설문조사. 국․내외 법 규정검토, 선행연구 분석을 통해 드렌처헤드 및 감지기, 드렌처설비 설치 층, 제어밸브 등에 대한 법적․제도적 개선이 필요함을 확인하였다.

纖維·어패럴 産業의 構造革新 方案

문철환 전북대학교 산업기술대학원 2008 국내석사

The purpose of this study is to analyze the industrial structure of Korean textile and apparel industries, and is to seek the plan to innovate the their structure. Korean textile industry, which served as the engine for our country's economic miracle in the 1960s, propelled Korea from a very undeveloped state to the upper echelon of the world's economic powers. Despite sluggish growth in recent years, the domestic textile industry remains a potent force. The companies in upstream textile industry are large as well as capital and technology intensive. Middle stream textile industries are small and medium as well as labor intensive depending on old equipments. In order to be more competitive, textile industry needs to develop more value-added and high quality product, responds quickly to the changes of demand patterns, enhances the capabilities if technological development, trains and educates human resources, establish a marketing strategy to increase export. Small-medium firms in middle stream should specialize in specific process like Italian firms so that firms networking whole process generate synergy effect of specialization. Upstream industries play a major role in innovation like Japanese firms utilizing economies of scale and or scope through vertical integration among development ? production ? marketing as well as horizontal differentiation of product in order to respond to market demand. This activity takes place along a variety of supply chains, including clothing, transportation, building construction, health care, home textiles, sports & leisure, military & defence amongst others. The latter part of the 20th Century was characterized by great scientific developments in microelectronics, computer science and biotechnology and these had a tremendous influence in the development of textile processing. At the present time, even though it is difficult to forecast the future, it is fundamental to endeavor to have a vision of the things to come in a particular area such as textiles. It is certain that the future of textiles will be shaped by trends in science, trade, business, art, culture, communications, politics and so on. Based upon this, the following trends in textile development seem quite to be apparent: ● The textile business is becoming global. ● Textile product development is multidisciplinary and so it should be the subject of team work. ● New and innovative applications of textiles are being sought all the time. This study examines the process of technological development and Korean firms' status in terms of technological competitiveness index among international textile industry and prospects the technological innovation in the textile industry.

스프링클러설비의 배관 부식에 대한 원인 분석과 개선방안에 관한 연구

문철환 부경대학교 2022 국내박사

In order to elucidate the causes of pipe corrosion in the sprinkler system, the problems were identified through the derivation of the planning stage problem and the analysis of the water quality in the fire safety water tank for maintenance, and through the experiments applying corrosion inhibitors as an improvement measure, the following conclusions were obtained. 1) The analysis using scanning electron microscopy(SEM) and energy-dispersive X-ray spectroscopy(EDS) to characterize the copper pipes in the sprinkler system showed that Cu was reduced by 30.12 wt%, and O and C increased by 19.85 wt% and 5.91 wt%, respectively, in the leaked pipe compared to the new one. 2) As for the problem of the change of pressure and flow rates due to aging of the pipe, when the friction loss coefficient of the pipe after 20 years of use was 90, the pressure was 0.0704 MPa and the flow rate 67.1 lpm at the terminal head, which did not satisfy the National Fire Safety Standards(NFSC). 3) In order to solve the problem of the 20-year-old pipe, the pump specifications of 2,600 lpm × 125 m were changed to 2,800 lpm × 155 m, and the use of the carbon steel pipe for pressure piping, which had been used only on the first basement floor, was expanded as the piping material up to 5 stories above the ground. It was confirmed that the pressure(0.1 MPa) and flow rate(80 lpm) at the terminal head required by the National Fire Safety Standards(NFSC) were satisfied. 4) As for the problem of the change of pressure and flow rates due to aging of the pipe, when the friction loss coefficient of the pipe after 30 years of use was 80, the pressure was 0.0584 MPa and the flow rate 61.1 lpm at the terminal head, which were inferior to the performances of the 20-year-old pipe. 5) In order to solve the problem of the 30-year-old pipe, the pump specifications of 2,600 lpm × 125 m were changed to 2,800 lpm × 155 m, and the use of the carbon steel pipe for pressure piping, which had been used only on the first basement floor, was expanded as the piping material up to 8 stories above the ground. As a result of such expanded application, it was confirmed that the pressure and flow rate at the terminal head conformed to the National Fire Safety Standards(NFSC). 6) The water quality analysis of the fire safety water tanks in three regions across the country confirmed that the water was in the quality that caused pipe corrosion as follows. (1) In the Busan region, 1,200 CFU/ml of general bacteria, which was 12 times higher than the value for the standard water quality, 100 CFU/ml or less, were detected, and the general E. coli was also detected. (2) In the Cheongju region, the turbidity was 0.99 NTU, which was approximately twice the standard value of 0.5 NTU. (3) In the Seoul region, 1,900 CFU/ml of general bacteria were detected, which was 19 times higher than the standard value for the water quality, 100 CFU/ml or less. (4) The water quality analysis in Busan, Cheongju and Seoul showed that pH 7 or lower and the water contained the components that could damage the protective film. 7) Through the experiment of injecting the fire safety water containing the corrosion inhibitor after discharging the existing fire safety water(tap water) inside the copper pipes for fire fighting facilities in 5 regions across the country, It was confirmed that the corrosion inhibitor is effective in improving the corrosion of pipes and reducing leakage. The following shows the experimental results of A (Jinju) area. (1) The water quality analysis showed that the average pH variated from 8.586 to 11.194 after the corrosion inhibitor injection into 5 copper pipes. (2) The average ORP decreased from -108.18 mV to -261.36 mV after the corrosion inhibitor injection into 5 copper pipes. (3) The average EC increased from 0.326 ms/cm to 4.889 ms/cm after the corrosion inhibitor injection into 5 copper pipes. 8) The results of analyzing the components attached to the surface of the sprinkler system according to the concentration and the impregnation period of the corrosion inhibitor in order to check whether the single molecule silica film was deposited on the copper pipe of the sprinkler system are as follows. (1) The component analysis after impregnation with 10,000 ppm of the corrosion inhibitor for 5 days showed that Cu decreased from 60.34 wt% to 20.57 wt% while O increased from 24.03 wt% to 62.28 wt%, and Si increased by 2.0 wt%. (2) The component analysis after impregnation with 10,000 ppm of the corrosion inhibitor for 10 days showed that Cu decreased from 67.72 wt% to 20.04 wt% while O increased from 23.71 wt% to 66.20 wt%, and Si increased by 1.97 wt%. (3) The component analysis on the surface after impregnation with 15,000 ppm of the corrosion inhibitor for 5 days showed that Cu decreased from 63.88 wt% to 2.61 wt% while O increased from 23.88 wt% to 85.96 wt%. (4) The component analysis after impregnation with 15,000 ppm of the corrosion inhibitor for 10 days showed that Cu decreased from 64.67 wt% to 6.38 wt%, while O increased from 24.34 wt% to 76.38 wt%, and Si increased by 4.59 wt%. (5) The component analysis on the surface of the copper specimen after impregnation with 100,000 ppm of the corrosion inhibitor for 10 days showed that Cu decreased from 55.93 wt% to 7.60 wt% while O increased from 24.65 wt% to 55.24 wt%, and the Si increased by 11.55 wt%.

유연 슈퍼커패시터용 미세구조 NiCo2S4의 음이온 결합 반응에 대한 연구

문철환 부산대학교 대학원 2017 국내석사

This paper proposes a novel and facile strategy to synthesize hierarchical nanostructured NiCo2S4 by a simple hydrothermal reaction combined with a post anion-exchange reaction that was used directly as an electrode in supercapacitor and quantum-dot sensitized solar cells. By applying the appropriate material concentration, deposition temperature, and time, the NiCo2S4 were densely deposited over the entire surface of the Ni foam with good adhesion. The electrode exhibited outstanding electrochemical performance in both the applications with a high specific capacitance of 1612.95 F/g, energy density of 56 Wh/kg at 5 A/g, good cycling stability, power conversion efficiency of 3.94 %, and Jsc of 12.27 mA/cm2. The NiCo2S4 electrode exhibited almost double the output values than that of NiCo2O4 (693.6 F/g at 6.66 A/g and efficiency of 1.81 %) and NiCo2Se (1401.4 F/g at 10 A/g and efficiency of 3.86 %), resulting from an excellent electrochemical performance of the NiCo2S4. Overall the fabricated electrode was attributed mainly to the highly electrocatalytic activity, surface area and the decent conductivity with hierarchical nanostructures of the NiCo2S4. This study shows that the NiCo2S4 nanostructure can be applied not only in high energy density fields, but also in high power density and energy harvesting applications.

Human Lysozyme 생산용 Vector 제작과 재조합 Saccharomyces cerevisiae를 이용한 생산증대

문철환 경남대학교 대학원 2002 국내석사

Surface treatment of carbon fibers for increasing interfacial characteristics

문철환 한양대학교 대학원 2014 국내박사

First, the anodic oxidation of carbon fibers was carried out to enhance the mechanical interfacial properties of carbon fibers-reinforced epoxy matrix composites. The anodic oxidation led to a significant change of surface characteristics of the carbon fibers. The anodic oxidation carbon fiber resulted in improving the mechanical interfacial properties, such as ILSS, KIC, and GIC of the composites. The mechanical interfacial properties of the composites anodized at 20% sulfuric/nitric (3:1) should the highest value among the anodized carbon fibers. These results were attributed to the increase of the degree of adhesion at interfaces between the carbon fibers and the matrix resins in the composite systems. Second, the atmospheric plasma treatment with He/O2 was conducted to modify the surface chemistry of carbon fibers. The effects of plasma treatment parameters on the surface energetics of carbon fibers were experimentally investigated with respect to gas flow ratio, power intensity, and treatment time. The results indicated that oxygen plasma treatment led to a large amount of reactive functional groups onto the fiber surface, and these groups can form together as physical intermolecular bonding to improve the surface wettability with a hydrophilic polymer matrix. Third, electroless plating of metallic nickel on carbon fiber surfaces was carried out to control specific electric resistivity of the fibers, and the effects of the nickel content and coating thickness on the electric properties were studied. From the XPS results, the oxygen and Ni atomic ratio of the fibers was greatly enhanced as the plating time increased. Additionally, it was observed that the specific electric resistivity decreased considerably in the presence of metallic nickel particles and with the formation of nickel layers on carbon fibers. Fourth, an effective new technique was developed to help carbon nanofibers (CNFs) grow on carbon fibers (CFs). The Ni catalyst was dispersed via three methods involving the synthesis of CNFs on CF surfaces. We found that high-density CNFs can be prepared by the decomposition of C2H2 on CF surfaces coated with a Ni-doped mesoporous silica film. The mesoporous silica film can direct the growth of CNFs from the CF surfaces when the distribution of Ni catalysts is controlled. The grown capability depends on the catalysts being highly dispersed into molecularly well-defined mesoporous silica structures by complexes of a surfactant with Ni cations. This method is more effective than other methods that involve such tasks as controlling the diameter of the CNFs, enhancing the contact between the CNFs and the CF surface, and eliminating the purification requirement of catalysts. SEM and TEM results indicate that the CNFs with a diameter between 20 and 70 nm grow uniformly and densely on CF surfaces.

Composite of Metal Sulfides as An Advanced Electrode Materials for High-Performance Supercapacitors

문철환 부산대학교 대학원 2022 국내박사

최근 슈퍼커패시터는 친환경성, 빠른 충방전율, 높은 전력밀도 및 긴 사이클 수명으로 인해 그 전기화학 저장장치로서 관심이 높아지고 있다. 슈퍼커패시터의 성능은 주로 전기활성 물질에 달려 있다. 전극 재료의 전하 저장 메커니즘을 기반으로 그래핀, 탄소 나노튜브 및 다공성 활성탄과 같은 탄소 재료는 전극-전해질 계면에서 전하를 축적한다. 반면 전기화학적 패러데이 산화환원 반응은 유사 커패시터/배터리 유형 전극 재료의 전기화학적 전하 저장을 담당한다. MnO2와 같은 유사 용량성 물질과 비교하여 배터리 유형 물질(Co3O4, Ni(OH)2, NiCo2O4, NiS, NiCo 층상 이중 수산화물(LDH) 등)은 높은 에너지 저장 특성으로 전해질 이온과의 확산 제어 전기화학적 산화환원 반응으로 인한 용량 값을 가지며 더 나은 에너지 저장 특성을 나타냈다. 위의 NiS 기반 하이브리드 전극 재료의 최근 결과에서 영감을 얻어 우리는 전기 활성 재료로서 두 개의 금속 황화물을 결합하는 개념을 조사하기 위해, 본 논문에서 간단한 2단계 화학 수조 증착 방법을 사용하여 NiS-PbS 마이크로플라워에 대한 효용성을 제안한다. 현재까지 슈퍼커패시터를 위한 새로운 클래스 전극 재료로서 NiS와 PbS의 조합에 대한 보고는 전무하다. 생성된 복합재는 2A g-1에서 125.89 mA h g-1의 더 높은 비용량, 10 A g-1에서도 용량이 114.67 mA h g-1을 유지하는 고용량 유지 및 길고 안정적인 사이클링 성능을 나타냈다. 사이클링 안정성의 경우 NiS 및 PbS 각각의 전극 재료보다 훨씬 우수한 3,000 사이클 후 88.97%를 유지하여 NiS-PbS 복합 재료가 에너지 저장에 대한 우수하고도 실용적인 응용 프로그램을 가지고 있음을 보여준다. Recently, supercapacitors have been gained considerable interest in the electrochemical storage devices owing to their environmentally friendliness, rapid charge/discharge rates, high power density as well as long cycle life. Supercapacitor performance is mainly depends on the electroactive material. Based on the charge storage mechanism of the electrode materials, carbon materials such as graphene, carbon nanotubes, and porous activated carbons accumulate the charge at the interfaces of electrode-electrolyte; whereas electrochemical Faradaic redox reactions are responsible for the electrochemical charge storage in pseudocapacitor/battery-type electrode materials. Compared to pseudocapacitive materials (such as MnO2), battery-type materials (such as Co3O4, Ni(OH)2, NiCo2O4, NiS, NiCo layered double hydroxides (LDHs), etc.) exhibited better energy storage properties due to their high-capacity values that result from the diffusion-controlled electrochemical redox reactions with electrolyte ions. Motivated from the recent results of above NiS-based hybrid electrode materials and to investigate the concept of combining two metal sulfides as the electroactive material, in this dissertation we proposed a NiS-PbS microflowers using simple two-step chemical bath deposition method. As we all know, to the date, there are no literatures on the combination of NiS with PbS as a new class electrode material for supercapacitor. The resulting composite exhibits a higher specific capacity of 125.89 mA h g-1 at 2 A g-1, high capacity retention that the capacity retained 114.67 mA h g-1 even at 10 A g-1, and a long stable cycling performance of retaining 88.97% after 3,000 cycles, which are much superior than the bare NiS and PbS electrode materials, revealing that the NiS-PbS composite have superior practical applications for energy storage.

The Organically modifled low-grade kaolin as a secondary containment for underground storage tanks

문철환 서울시립대학교 University of seoul 2004 국내석사

The Organically modified low-grade kaolin as a secondary containment for underground storage tanks

Moon, Chul-Hwan 서울시립대학교 2004 국내박사