• 제목/요약/키워드: Functional Fluids

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Simple Tools for Ink Jet Printing of Functional Fluids

  • Schoeppler, Martin W.;Creagh, Linda T.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1657-1659
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    • 2006
  • Success in moving ink jets into newer areas such as printing on to-be-defined flexible substrates or developing new functional fluids requires both process and fluid research and engineering. Today, leading-edge concepts are slow to be explored because of the expense and complexity of commercially available ink jet deposition systems, time and resources required to specify and acquire commercial ink jet systems and the expertise required to operate commercial ink jet systems.

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The Effect of Compressing ER Electrode on Electrorheological Properties of Anhydrous ER Fluids (ER 유체용 압축전극이 ER 유체의 전기유변학적 특성에 미치는 영향)

  • Ahn, Byeng-Gil
    • Tribology and Lubricants
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    • 제18권1호
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    • pp.16-23
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    • 2002
  • For increasing the yield stress of ER fluids, the compressing ER electrode was developed and the compressing electrorheological (ER) behavior of anhydrous ER fluids in silicone oil of phosphorous ester cellulose powder was investigated. Under constant electric field, not only the current density but also the yield stress of anhydrous ER fluids were studied as varying the compressing length of ER electrode distance. From the experimental results the compressing of ER electrode had a large influence to the ER properties of anhydrous ER fluids. The current density was proportional to the compressing length of ER electrode under constant electric field and volume fraction also tile compressing yield stress was proportional to the volume fraction of dispersed particles under constant electric field and compressing length. When the ER electrode was compressed with 150mm after charging the electric field, 4 kV, tile yield stress of phosphoric ester cellulose ER fluids increased to thirteen times comparing with the yield stress measured at normal electrode.

Liquid Cooling System Using Planar ECF Pump for Electronic Devices (평면형 ECF 펌프를 이용한 전자기기 액체냉각 시스템)

  • Seo, Woo-Suk;Ham, Young-Bog;Park, Jung-Ho;Yun, So-Nam;Yang, Soon-Young
    • Journal of the Korean Society for Precision Engineering
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    • 제24권12호
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    • pp.95-103
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    • 2007
  • This paper presents a liquid cooling concept for heat rejection of high power electronic devices existing in notebook computers etc. The design, fabrication, and performance of the planar ECF pump and farced-liquid cooling system are summarized. The electro-conjugate fluid (ECF) is a kind of dielectric and functional fluids, which generates jet flows (ECF-jets) by applying static electric field through a pair of rod-like electrodes. The ECF-jet directly acts on the working fluid, so the proposed planar ECF pump needs no moving part, produces no vibration and noise. The planar ECF pump, consists of a pump housing and electrode substrate, achieves maximum flow rate and output pressure of $5.5\;cm^3/s$ and 7.2 kPa, respectively, at an applied voltage of 2.0 kV. The farced-liquid cooling system, constructed with the planar ECF pump, liquid-cooled heat sink and thermal test chip, removes input power up to 80 W keeping the chip surface temperature below $70\;^{\circ}C$. The experimental results demonstrate that the feasibility of forced-liquid cooling system using ECF is confirmed as an advanced cooling solution on the next-generation high power electronic devices.

Supercritical Fluids and Preparation of Porous Materials (초임계 유체 및 다공성 소재 제조 기술)

  • Lee, Jun-Young;An, Joon-Hyun;Kim, Jung-Hyun
    • Applied Chemistry for Engineering
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    • 제16권2호
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    • pp.169-179
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    • 2005
  • Porous materials are useful in a wide range of applications including bio/electronic products. The preparation and processing of these materials are mainly progressed by using an organic solvent, which gives rise to air pollution by its emissions. Alternatively, supercritical fluids are well suited to the production of functional porous materials due to a number of specific physical, chemical, and toxicological advantages. In this review, we will introduce the preparation and processing techniques for the formation of the nano/macro pore structure and their morphology, which can be controled by using supercritical fluids.

The Study about Characteristics Affecting Functional Recovery of Stroke Patients Treated in an Oriental Medical Center (한방병원에 입원한 뇌경색 환자의 기능회복과 관련된 특성에 대한 연구)

  • Kim, Young-Jee;Kim, Mi-Young;Lee, Seung-Yeop;Choi, Won-Woo;Park, Joo-Young;Kwon, Seung-Won;Jung, Woo-Sang;Moon, Sang-Kwan;Cho, Ki-Ho;Kim, Young-Suk;Park, Sung-Wook;Park, Jung-Mi;Ko, Chang-Nam;Bae, Hyung-Sup;Na, Byong-Jo
    • The Journal of Internal Korean Medicine
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    • 제30권4호
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    • pp.719-731
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    • 2009
  • Objectives : Stroke is the most common disabling neurological disease of adult life. The treatment and rehabilitation of stroke patients is an important and challenging area in the field of medicine. In Korea, a lot of stroke patients are treated using oriental medicine and there have been reports on their functional recovery. The aim of this study was to prove the therapeutic effect of oriental medicine on ischemic stroke. We also tried to identify characteristics of patients whose functional recovery was prominent and studied whether or not the use of fluids, anticoagulants, antiplatelets and neuroprotective agents increased the functional recovery of patients. Methods : We studied 794 patients within 2 weeks after first attack of ischemic stroke who were admitted to Kyung-Hee Oriental Medical Center from 1999 to 2000. Their maximum admission period was 60 days. Results : Motor power grade, NIHSS and MBI scores of patients improved during hospitalization significantly. Factors affecting functional recovery were admission period, motor power grade, NIHSS and MBI at admission. Age, waist-hip ratio and HDL cholesterol also affected functional recovery of patients. Whether or not fluids, anticoagulants, antiplatelets and neuroprotective agents were administered had nothing to do with functional recovery. Conclusion : Oriental medicine is effective for treatment and rehabilitation of ischemic stroke patients. When we manage stroke, we have to consider some important factors.

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A SATELLITE ELECTRONIC EQUIPMENT THERMAL ANALYSIS USING SEMI-EMPERICAL HEAT DISSIPATION METHOD (반실험적 열소산 방법을 이용한 위성용 전장품 열해석)

  • Kim Jung-Hoon;Jun Hyung-Yoll;Yang Koon-Ho
    • Journal of computational fluids engineering
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    • 제11권2호
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    • pp.32-39
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    • 2006
  • A heat dissipation modeling method of EEE parts is developed for thermal design and analysis of an satellite electronic equipment. The power consumption measurement value of each functional breadboard is used for the heat dissipation modeling method. For the purpose of conduction heat transfer modeling of EEE parts, surface heat model using very thin ignorable thermal plates is considered instead of conventional lumped capacity nodes. These modeling methods are applied to the thermal design and analysis of CTU EM and EQM and verified by thermal cycling and vacuum tests.

Innovations in Materials Deposition for Plastic Electronics

  • Creagh, Linda T.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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    • pp.673-675
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    • 2005
  • Ink jet printheads are now widely used in manufacturing processes that require precise dispensing of materials. Today, Dimatix manufactures a variety of drop-on-demand ink jet printheads for the industrial printing market, but emerging opportunities present fresh challenges to our technology. In response to requirements for digitally printing on flexible substrates and dispensing novel electronic fluids, we are developing next generation jetting technology based on our three-dimensional silicon MEMS technology with a piezo-driven pumping chamber integrated into the chip structure. This presentation will address the functional and physical design features and properties of Dimatix's MEMS process, its characteristics, reliability and usability. Examples of opportunities and applications for digitally printing electronic fluids on flexible substrates with MEMS-based ink jet technology will be presented.

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Vaporization and Conversion of Ethanolamines used in Metalworking Operations

  • Kim, Shin-Bum;Yoon, Chung-Sik;Park, Dong-Uk
    • Safety and Health at Work
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    • 제1권2호
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    • pp.175-182
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    • 2010
  • Objectives: This study examined how ethanolamines (EAs) with the same functional alcohol group ($HOCH_2CH_2$), such as mono-EA (MEA), di-EA (DEA), and tri-EA (TEA), in water-based metalworking fluids (wbMWFs) are vaporized, condensed, and transformed by heat generated during metalworking. Methods: Two types of experimental apparatus were manufactured to achieve these objectives. Results: Vaporization tests using a water bath showed that the vaporization rate increased markedly from $0.19\;mg/m^2{\cdot}min$ at $23.5^{\circ}C$ to $8.04\;mg/m^2{\cdot}min$ at $60^{\circ}C$. Chamber tests with a heat bulb revealed that "spiked" MEA was fully recovered, while only 13.32% of DEA and no TEA were recovered. Interestingly, non-spiked types of EAs were detected, indicating that heat could convert EAs with more alcohol groups (TEA or DEA) into other EAs with fewer group(s) (DEA or MEA). The EA composition in fresh fluid was 4% DEA, 66% TEA, and 30% MEA, and in used fluids (n = 5) was 12.4% DEA, 68% TEA, and 23% MEA. Conversion from TEA into DEA may therefore contribute to the DEA increment. Airborne TEA was not detected in 13 samples taken from the central coolant system and near a conveyor belt where no machining work was performed. The DEA concentration was $0.45\;mg/m^3$ in the only two samples from those locations. In contrast, airborne MEA was found in all samples (n = 53) regardless of the operation type. Conclusion: MEAs easily evaporated even when MWFs were applied, cleaned, refilled, and when they were in fluid storage tanks without any metalworking being performed. The conversion of TEA to DEA and MEA was found in the machining operations.

Biomedicinal implications of high-density lipoprotein: its composition, structure, functions, and clinical applications

  • Cho, Kyung-Hyun
    • BMB Reports
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    • 제42권7호
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    • pp.393-400
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    • 2009
  • High-density lipoprotein (HDL) is a proven biomarker for the monitoring of changes in antioxidant and anti-inflammation capability of body fluids. The beneficial virtues of HDL are highly dependent on its lipids and protein compositions, and their ratios. In normal state, the HDL particle is enriched with lipids and several HDL-associated enzymes, which are responsible for its antioxidant activity. Lower HDL-cholesterol levels (<40 mg/dL) have been recognized as an independent risk factor for coronary artery disease, as well as being a known component of metabolic syndrome. Functional and structural changes of HDL have been recognized as factors pivotal to the evaluation of HDL-quality. In this review, I have elected to focus on the functional and structural correlations of HDL and the roles of HDL-associated apolipoproteins and enzymes. Recent clinical applications of HDL have also been reviewed, particularly the therapeutic targeting of HDL metabolism and reconstituted HDL; these techniques represent promising emerging strategies for the treatment of cardiovascular disease, for drug or gene therapy.

Torsional Vibration Damper Using Magneto-Rheological Fluid (MR 유체를 이용한 비틀림진동 감쇠기)

  • 안영공;신동춘;양보석;김동조
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 한국소음진동공학회 2001년도 춘계학술대회논문집
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    • pp.313-317
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    • 2001
  • Magneto-Rheological fluid (MR fluid) is known as a class of functional fluid with controllable apparent viscosity of the fluid by the applied magnetic field strength. Extensive researches with the functional fluids have been done on applications of the fluid to mechanical components such as suspension, absorber, engine mount, clutch, break, valve, etc. In this study, a new torsional damper using MR fluid is proposed, and the response property of the damper was theoretically investigated. The present damper is quit effective for reducing the driveline vibration in a wide range of the engine speed.

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