• 제목/요약/키워드: electro-chemical systems

검색결과 64건 처리시간 0.033초

Fluorescent Probes for Analysis and Imaging of Monoamine Oxidase Activity

  • Kim, Dokyoung;Jun, Yong Woong;Ahn, Kyo Han
    • Bulletin of the Korean Chemical Society
    • /
    • 제35권5호
    • /
    • pp.1269-1274
    • /
    • 2014
  • Monoamine oxidases catalyze the oxidative deamination of dietary amines and amine neurotransmitters, and assist in maintaining the homeostasis of the amine neurotransmitters in the brain. Dysfunctions of these enzymes can cause neurological and behavioral disorders including Parkinson's and Alzheimer's diseases. To understand their physiological roles, efficient assay methods for monoamine oxidases are essential. Reviewed in this Perspective are the recent progress in the development of fluorescent probes for monoamine oxidases and their applications to enzyme assays in cells and tissues. It is evident that still there is strong need for a fluorescent probe with desirable substrate selectivity and photophysical properties to challenge the much unsolved issues associated with the enzymes and the diseases.

고분자 이온교환막의 제조와 이온교환막을 이용한 에너지 공정 (The Fabrication of Ion Exchange Membrane and Its Application to Energy Systems)

  • 김재훈;류승보;문승현
    • 멤브레인
    • /
    • 제30권2호
    • /
    • pp.79-96
    • /
    • 2020
  • 환경오염과 화석연료의 문제로 인한 2차 에너지 변환 및 저장 장치의 개발이 활발하게 진행되고 있다. 이러한 에너지 변환장치들은 전기화학적 시스템을 기본으로 운영되고 있으며 이온교환막은 각 공정의 성능을 결정짓는 중요한 요소이다. 따라서 에너지 시스템의 효율 증대 및 성능 향상을 위해서는 적합한 물성을 갖는 이온교환막 개발이 필요하다. 이러한 이온교환막은 크게 양이온교환막, 음이온교환막, 바이폴라막으로 분류되고 있으며, 이들 막들은 화학적, 물리적, 형태학적 특성에 따라 다양한 용도을 갖고 있다. 본 총설에서는 이온교환막의 주요한 특징과 함께 이들의 제조 방법에 대해 기술했다. 이어서 이온교환막을 이용하여 최근 개발되고 있는 전기화학 시스템에 기반을 둔 역전기 투석, 레독스 흐름 전지, 수전해 공정에 대해서 소개하고, 각 에너지 공정에서 이온교환막이 갖는 역할과 조건에 대해서 설명하였다.

전기화학 기계적 연마를 이용한 Cu 배선의 평탄화 (Planarization of Cu intereonnect using ECMP process)

  • 정석훈;서현덕;박범영;박재홍;이호준;오지헌;정해도
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
    • /
    • pp.79-80
    • /
    • 2007
  • Copper has been used as an interconnect material in the fabrication of semiconductor devices, because of its higher electrical conductivity and superior electro-migration resistance. Chemical mechanical polishing (CMP) technique is required to planarize the overburden Cu film in an interconnect process. Various problems such as dishing, erosion, and delamination are caused by the high pressure and chemical effects in the Cu CMP process. But these problems have to be solved for the fabrication of the next generation semiconductor devices. Therefore, new process which is electro-chemical mechanical planarization/polishing (ECMP) or electro-chemical mechanical planarization was introduced to solve the. technical difficulties and problems in CMP process. In the ECMP process, Cu ions are dissolved electrochemically by the applying an anodic potential energy on the Cu surface in an electrolyte. And then, Cu complex layer are mechanically removed by the mechanical effects between pad and abrasive. This paper focuses on the manufacturing of ECMP system and its process. ECMP equipment which has better performance and stability was manufactured for the planarization process.

  • PDF

Unique Fluid Ensemble including Silicone Oil for the Application of Optical Liquid Lens

  • Bae, Jae-Young;Park, Sung-Soo;Kim, Jae-Hong;Park, Chin-Ho;Choi, Young-Chul;Jung, Ha-Yong
    • Bulletin of the Korean Chemical Society
    • /
    • 제29권4호
    • /
    • pp.731-735
    • /
    • 2008
  • The fluid ensemble in the liquid lens, which is composed of electrolyte and silicone oil, is the key material system to vary the focal length processing of the electrochemical desorption. In order to characterize the capability of the liquid lens according to response time and optical range, we prepared a fluid ensemble comprising the electrolyte and oil. To elucidate the physical mechanism of the effective response time, we examined the viscosity dependency while satisfying the requirements for the density and refractive index of the electrolyte and oil, respectively. The characterization results indicated that the response time (up and down) is influenced by the viscosity of the electrolyte and oil. On this basis, we prepared a fluid ensemble capable of reversibly adjusting for the focal length of the liquid lens, as well as the response time. The ensemble is applicable to various systems such as micro-lens and optical sensors.

2차원 ZnO 나노벽 구조 제조 (Fabrication of 2-Dimensional ZnO Nanowall Structure)

  • 김영정;;김영철;안승준;민준원
    • 한국세라믹학회지
    • /
    • 제42권7호
    • /
    • pp.521-524
    • /
    • 2005
  • ZnO 2-D nanowall structure with around 100 nm thickness, which is composed of tens of nm scale ZnO single crystals, was fabricated through the low temperature chemical solution growth method. Electro Chemical Deposition (ECD) technique was applied to attach the ZnO seed crystals on ITO coated glass substrate. The ZnO nanowall structure was grown in the 0.015 mol$\%$ of aqueous solution of zinc nitrate and hexamethenamine at 60$^{\circ}C$ for 20 - 40 h. The nanowall structure depends on the ECD condition or the applied voltage and duration time. The nanowall shows a photoluminescence around 550 - 700 nm spectrum range.

DLC 박막을 통한 전자광학추적장비 신뢰성 개선 (Reliability Improvement of the Electro Optical Tracking System by using DLC Films)

  • 심보현;조희진;김장은
    • 전자공학회논문지
    • /
    • 제52권5호
    • /
    • pp.197-205
    • /
    • 2015
  • 함정용 전자광학추적장비 열영상센서부 전면창의 신뢰성 및 성능 개선을 위해 플라즈마 화학기상증착법을 통해 제작되는 DLC 박막을 제안하였다. DLC 박막은 현재 사용되고 있는 실리콘 박막과 비교하여 뛰어난 강도와 낮은 마찰, 화학적 안정성이 우수하며 이로 인해 해상 환경에서 필연적으로 발생하는 열영상센서 전면창의 표면 박리를 최소화할 수 있는 장점이 있다. 본 실험을 통해, DLC 박막이 갖는 물리적 특성을 바탕으로 다양한 전자광학장비에 적용이 가능함을 확인하였다.

전기가변 고분자 소재를 이용한 응용소자 (Electro-active Polymer and Dielectric Elastomer Technology for Haptic Interface, Muscular Enhancement, and Tunable Optical Components)

  • 윤재웅;박승구;문성철
    • 전자통신동향분석
    • /
    • 제34권4호
    • /
    • pp.108-116
    • /
    • 2019
  • Electro-active polymers and dielectric elastomers have many intriguing properties that enable smart interfaces and electrically tunable optical systems, such as haptic feedback devices, artificial muscles, and expansion-tunable optical elements. These device classes are of great interest owing to their promising roles in next-generation technologies including virtual or augmented reality, human sensing and muscular enhancement, and artificial skins. In this report, we review basic principles, current state-of-the-art techniques, and future prospects of electro-active and dielectric elastomer technology. We describe chemical and physical properties of the most promising polymer substances, essential elementary architectures for artificial muscle-like functionalities, and their applications to haptic interfaces, muscular enhancement, and focus-tunable optical elements.

Fabrication of Electro-active Polymer Actuator Based on Transparent Graphene Electrode

  • Park, Yunjae;Choi, Hyonkwang;Im, Kihong;Kim, Seonpil;Jeon, Minhyon
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
    • /
    • pp.386.1-386.1
    • /
    • 2014
  • The ionic polymer-metal composite (IPMC), a type of electro-active polymer material, has received enormous interest in various fields such as robotics, medical sensors, artificial muscles because it has many advantages of flexibility, light weight, high displacement, and low voltage activation, compare to traditional mechanical actuators. Mostly noble metal materials such as gold or platinum were used to form the electrode of an IPMC by using electroless plating process. Furthermore, carbon-based materials, which are carbon nanotube (CNT) and reduced graphene-CNT composite, were used to alter the electrode of IPMC. To form the electrode of IPMC, we employ the synthesized graphene on copper foil by chemical vapor deposition method and use the transfer process by using a support of PET/silicone film. The properties of graphene were evaluated by Raman spectroscopy, UV/Vis spectroscopy, and 4-point probe. The structure and surface of IPMC were analyzed via field emission scanning electron microscope. The fabricated IPMC performance such as displacement and operating frequency was measured in underwater.

  • PDF