Graphene Oxide Incorporated Antifouling Thin Film Composite Membrane for Application in Desalination and Clean Energy Harvesting Processes

이대원,라즈쿠마 파텔,Lee, Daewon,Patel, Rajkumar The Membrane Society of Korea 2021 멤브레인 Vol.31 No.1

Water supplies are decreasing in comparison to increasing clean water demands. Using nanofiltration is one of the most effective and economical methods to meet the need for clean water. Common methods for desalination are reverse osmosis and nanofiltration. However, pristine membranes lack the essential features which are, stability, economic efficiency, antibacterial and antifouling performances. To enhance the properties of the pristine membranes, graphene oxide (GO) is a promising and widely researched material for thin film composites (TFC) membrane due to their characteristics that help improve the hydrophilicity and anti-fouling properties. Modification of the membrane can be done on different layers. The thin film composite membranes are composed of three different layers, the top filtering active thin polyamide (PA) layer, supporting porous layer, and supporting fabric. Forward osmosis (FO) process is yet another energy efficient desalination process, but its efficiency is affected due to biofouling. Incorporation of GO enhance antibacterial properties leading to reduction of biofilm formation on the membrane surface. Pressure retarded osmosis (PRO) is an excellent process to generate clean energy from sea water and the biofouling of membrane is reduced by introduction of GO into the active layer of the TFC membrane. Different modifications on the membranes are being researched, each modification with its own advantages and disadvantages. In this review, modifications of nanofiltration membranes and their composites, characterization, and performances are discussed. 물 공급은 늘어나는 담수 수요와 다르게 줄어들고 있다. 담수의 수요를 충당하기 위해서 나노여과법은 가장 효율적이고 경제적인 방법이라고 할 수 있다. 해수담수화를 위한 나노여과법의 일반적인 방법으로는 나노여과 멤브레인을 이용한 역삼투압 방식이다. 하지만 기존의 멤브레인들은 주요 특성인 안정성, 경제성, 그리고 살균 및 방오특성이 부족하다. 기존의 나노여과 멤브레인을 향상시키기 위해서 친수성과 방오성이 높은 흑연 산화물이 가장 향상성이 높으며 널리 연구되고 있는 재료이다. 멤브레인 변형은 다른 레이어에 적용될 수 있다. 얇은 막으로 이루어진 멤브레인은 다른 세 레이어로 구성되어 있다, 표면의 폴리아미드 레이어, 기공 레이어, 그리고 전체적인 구조를 구성하는 지원 직물이다. 정삼투압 토한 에너지 효율적인 해수담수화 방식이지만 효율이 생물 오염 때문에 떨어진다. 산화그래핀 결합은 향균 기능을 향상할 수 있으며 멤브레인 표면에 바이오필름 생성을 억제할 수 있다. 압력지연삼투는 해수에서 청정에너지를 발전시키는 최고의 방법 중 하나이다. 멤브레인의 생물 오염은 합성 폴리머 멤브레인의 합성 레이어에 산화 그래핀을 합성하여 줄일 수 있다. 나노여과 멤브레인을 개량하는 여러 연구가 각자의 장단점을 가지고 이루어지고 있다. 이 보고서는 나노여과 멤브레인의 개량, 성질, 그리고 성능에 대해 논의한다.

다동온실내 복합환경 제어용 하드웨어 시스템의 개발

이대원,김채웅,김재민 성균관대학교 생명과학자원연구소 1997 生命資源科學硏究 Vol.4 No.2

Growth of plants in greenhouses is increasing in popularity across Korea. Automatic hybrid environmental hardware system, including main module, display module, sensor module, input module, output module with one chip CPU controller, EPROM, SRAM, multi task interrupt controller, operating equipment and many sensors, appears to be an attractive alternative to the use of manual labor for accomplishing this task. Each module was made to slots, which are very convenient to mount and take off. Also, it is managed easily to repair, add, remove, and change their function and expansion. This research developed the hardware system for automatic hybrid environmental control. Separate programs for control of the hardware and for optimal analysis of the software, written Visual Basic, Turbo-C and Assembler, were developed to make the automatic hybrid environmental control system operated. The objective of this research designed and constructed a hybrid environmental hardware system for the optimal growth of plants within a greenhouse environment.

다동온실의 복합환경 제어시스템을 위한 소프트웨어 개발

이대원,김채웅 성균관대학교 생명공학연구소 1999 生命工學硏究 Vol.5 No.1

A hybrid environmental control system was designed and built in the multi-greenhouses. After the hardware system was developed, the software was designed and constructed for this project. A software was adequate for reading data from many sensors and operating side windows, top windows, curtains and fans in the two greenhouses. Separate programs for control of the hardware, written Visual basic, Turbo-C and Assembler computer language, were developed to make the hybrid environmental control system operate. The program was a menu driven program within Windows environment. The initial menu was easily implemented by pressing a keypad key(KPK) on the keyboard or a mouse. Continued manipulation of the KPK or a mouse enable the user to reach easily any of the sub modes in the many modes. This software proved to be a reliable program for the hybrid environmental control system in the two greenhouse.

플라즈마를 이용한 디젤 PM 저감 기술

이대원 한국공기청정협회 2003 空氣淸淨技術 Vol.16 No.2

칼라센서를 이용한 담배 완숙도의 식별장치 개발

이대원,이용국 한국연초학회 1994 한국연초학회지 Vol.16 No.1

A tobacco ripeness grading meter was designed and constructed using the color sensor, its performance was evaluated. A degree of ripeness grading of a leaf is very closely related to the measured tobacco leaf color. Measuring the small amount of the reflectance precisely depends on the apparatus including color sensor, light source, detector sensitivity, and geometric characteristics of appratus. To analyze and minimize the variational effects, experiments to select the proper condition were performed. Because of the combined effect mentioned above, the system has some variation on its response. Basis on the results of the experiments, prototype was developed and interfaced to a computer system. The main components of prototype included a tungsten lamp as a light source, Amorphous full color sensor with three filters, regulated D.C. power supply, OP - AMP(741 TC) for amplification, AR - B3001 board for interfacing to a computer with analog to digital conversion, and a compatible IBM PC XT computer. The experimental results of the developed ripeness tobacco leaf measurement system are summarized as following: [1] The output readings of ripeness grade meter for tobacco leaf, which is based on harvesting time, showed the apparent difference in variety of different quality. It was considered suitable that three filters(red, green, blue) in Amorphous full color sensor could be used in four different ripeness degree measurement of tobacco leaf. [2] The output readings of ripeness grade meter for tobacco leaf, which is based on government procurement, showed apparent difference in variety of different quality. Tobacco leaf varieties to stalk position are divided into tips, leaf, cutters, and primings, It is considered suitable that only red filter in the sensor could be used to classify the grade of tobacco leaf within the same kind tobacco stalk. However, the ripeness grade meter was not adequate to classify all the tobacco grades in the four different tobacco leaves.

Crystallization Effect on the Morphology of PEG-PTMO Multiblock Copolymers

이대원,이승헌,차국헌,박재형,배유한 한국고분자학회 2000 한국고분자학회 학술대회 연구논문 초록집 Vol.2000 No.10

현호색(Corydalis remata for remota)의 다양한 조직으로 부터 기내배양을 통한 체세포 배발생

이대원,천우재 동국대학교 경주대학 1999 東國論集 Vol.18 No.-

For the induction of somatic embryogenic callus, the various explants of Corydalis remota for. remota were cultured on MS basal media supplemented with 2,4-D, kinetin and zeatin. Embryogenic calli were obtained from the leaf, stem, penduncle and root explants after 20-60 days. The highest embryogenic callus formation was observed from leaf on the media containing 1.0 ㎎/L of 2,4-D and 1.0 ㎎/L of kinetin. the somatic embryogenesis on the media with 0.1 ㎎/L of 2,4-D 2 ㎎/L of kinetin were excellent under light condition. Generally the somatic embryos were abnormally developed into plantlets. However, normal decotyledonary plantlets were found on MS medium supplemented with 1.0 ㎎/L of zeatin or kinetin. When MS medium with 2,4-D plus cytokinin and with BAP were used, the secondary somatic embryogenesis took place in root explants of the regenerants derived from in vitro somatic embryogenic callus.

지리산 학교와 길에서 만난 생명과 평화

이대원 우리신학연구소 2008 갈라진 시대의 기쁜소식 Vol.- No.849

강원지역 화학공학 혁신기술 학술심포지엄 행사보고

이대원 한국화학공학회 2018 NICE Vol.36 No.1

로봇 포도수확기를 위한 엔드이펙터 개발

이대원,김현태,이용국 성균관대학교 생명공학연구소 2001 生命工學硏究 Vol.7 No.1

Most of fruits need laboring greatly to harvest fruit in the period of harvest season. Grape also needs requiring a lot of labor to harvest in time, since harvesting of grape is cut and graped by hand. At abroad, especially, a harvester of grape, which is not eat freshly raw grape fruit but is processed to be made wine, was developed in France. However, a harvester of grape which can eat freshly raw grape fruit haven't not been developed. Therefore, this study was designed and constructed to develope an end effector of the robotic harvesting system. In order to find average and standard deviation of size and shape of a bunch grape, the grape farm was visited and investigated to find out the important factors for end effector to be designed and built. The efficient end-effecter should reach very well a bunch of grape without touching obstacles, such as leaf and stem in the grape vine. Also, it was made as simple, small and light as possible. Therefore, It was made of duralumin, which was lighter material than iron, to reach easily fresh grape fruit and reduce a torque. After finding the optimum initial speed, slew speed, ramp speed, the end effector proved to be a smooth operating end effector. For verifying efficiency of the end-effecter, the control board was designed and manufactured, and also developed the software to control the motors of the end effector.