• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.6
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• pp.750-756
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• 1985

Experimental investigation was carried out to study the natural convection of water and silicon oil due to end temperature differences in a horizontally insulated rectangular enclosure of aspect ratio 0.1 with a special attention on the core configuration in the laminar boundary-layer flow regime. Rayleigh number ranges covered herein are Ra=4.40 * 10$^{6}$ -9.64 * 10$^{7}$ for water and Ra=1.69*10$^{5}$ -3.80*10$^{6}$ for silicon oil, respectively. In the case of water, for Ra.geq.2.21 * 10$^{7}$ there appeared distinct horizontal thermal layers adjacent to the horizontal boundaries in the core and the temperature distribution outside the horizontal thermal layers, i.e., in the mid-core region, is vertically stratified. The core flow pattern was shown to be nonparallel with a weak back flow in the mid-core for Ra.geq.3.63 *10$^{7}$ . In the case of silicon oil, distinct horizontal thermal layers appeared along the core horizontal boundaries for Ra.geq.1.27 * 10$^{6}$ with a stratified temperature distribution in the mid-core, but the core flow pattern in this case was shown to be parallel. In addition, secondary flow appeared near the hot wall for Ra.geq.3.80 * 10$^{6}$ . Nusselt number, Nu, was found to be proportional to R $a^{0.3}$ for water and R $a^{0.28}$ for silicon oil in the boundary-layer flow regime. There also in an indication from the comparison with other results that Nu is independent of aspect ratio for water in the boundary-layer flow regime in low aspect ratio enclosures.res.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.3
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• pp.202-208
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• 2017

The recently developed marine engines for propulsion of ships have higher torsional exciting force than previous engines to improve the propulsion efficiency and to reduce specific fuel oil consumption. As a result, a viscous damper or viscous-spring damper is installed in front of marine engine to control the torsional vibration. In the case of viscous damper, it is supposed that there is no elastic connection in the silicon oil, which is filled between the damper housing and inertia ring. However, In reality, the silicon oil with high viscosity possesses torsional stiffness and has non-linear dynamic characteristics according to the operating temperature and frequency of the viscous damper. In this study, the damping characteristics of a viscous damper used to control the torsional vibration of the shafting system have been reviewed and the characteristics of torsional vibration of the shafting system equipped with a corresponding viscous damper have been examined. In addition, it is examined how to interpret the theoretically optimal dynamic characteristics of a viscous damper for this purpose, and the optimum design for the propulsion shafting system has been suggested considering the operating temperature and aging. when the torsional vibration of the shafting system is controlled by a viscous damper filled with highly viscous silicon oil.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.6
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• pp.998-1002
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• 2012

This paper investigates the behavior of bubbles trapped in the in-mold coating (IMC) process. Silicon oil with different viscosity, 100, 150, 200, 300 and 400cps, was selected instead of the coating materials. To observe the flow front inside, a special mold was designed, where front plate was made of transparent material (acrylate). The overall size of front plate was $150mm{\times}120mm$. Mold gate location can be changed from up to down. Four heaters were used to investigate the effectiveness of temperature. The results show that silicon viscosity, mold gate location and mold temperature play an important role on the appearance of bubbles trapped in IMC process.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.607-612
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• 2021

Silicon (Si) is one of the promising active materials to replace the widely used graphite because of its low electrochemical potential and high theoretical capacity. However, Si anodes still face in problems with the huge volume expansion and continuous decomposition of the electrolyte during repeated charge and discharge processes. To address these issues, a cross-linkable waterborne polyurethane (CWPU) based on a bio-oil, castor oil, was prepared and reacted with Tris(2,3-epoxypropyl) isocyanurate (TGIC) linkers, resulting in the formation of a mechanically robust 3D network structure. Si anodes fabricated with the CWPU-TGIC exhibited stable cycling performances and excellent discharge capacities. The results revealed that the CWPU-TGIC binder efficiently accommodates the large volume change for Si anode during charge and discharge cycles. Overall, the eco-friendly binder shows great promise in improving the electrochemical performances of Si anodes.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.113-118
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• 2011

Many kinds of dynamic absorbers have been used to reduce the vibration of machineries and structures. In the typical ones, however low damping capacity, durability and limited install condition restrict their application. In this study, high damped dynamic absorber was proposed for diesel generator set. Developed absorber is composed with mass and coil springs. Silicone oil was filled inside the narrow gap between mass and casing. Viscous damping of silicon oil act as additional damping so that proposed dynamic absorber is suitable for D/G set which have adjacent resonance frequency to operation speed. The performance of the dynamic absorber was confirmed through the actual test on diesel engine generator set.

• Resources Recycling
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• v.22 no.2
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• pp.37-43
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• 2013

Unlike the conventional slurry type wire sawing, the diamond wire sawing method adopts diamond plated wire as sawing media instead of slurry consisted of both silicon carbide and oil. Wafering with diamond plated wire leaves solid element of the sludge mostly made up of silicon, and it is not difficult to recover 95% or more of silicon by a simple separation process of oil from the sludge. In this study, silicon was recovered from the sludge by drying process and organic and metal impurities were removed by sintering process. As result 3N grade silica was obtained successfully by thermal processing utilized the fact that the recovered silicon readily combines with oxygen due to fine particle size.

• Tuberculosis and Respiratory Diseases
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• v.69 no.4
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• pp.288-292
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• 2010

Exogenous lipoid pneumonia occurs rarely in healthy people. In most cases, exogenous lipoid pneumonia is usually caused by aspiration of mineral, vegetable, or animal oil. We report the case of 42-year-old woman, who have experienced lipoid pneumonia after silicon injection into her breast for cosmetic purposes. The patient experienced fever, dyspnea, sputum, and hemoptysis after silicon injection into her breast. Chest computed tomography demonstrated non- segmental distribution of bilateral consolidation in both lung fields. A transbronchial lung biopsy specimen shows foamy microphages in alveolar spaces. Papanicolaous staining of bronchoalveolar lavage fluid showed abundant foamy marcrophages and many neutrophils. With these results, we confirmed lipoid pneumonia was associated with silicon oil injection into breast.

• Journal of Sensor Science and Technology
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• v.25 no.5
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• pp.344-348
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• 2016

We developed a 2-channel fiber-optic temperature sensor (FOTS) using a temperature sensing probe, a fiber-optic coupler, transmitting optical fiber, and an optical time domain reflectometer (OTDR). The temperature sensing probe is divided into a sensing probe and a reference probe for accurate thermometry. A sensing probe is composed of a silicon oil, a FC terminator, a brass pipe, and a singlemode optical fiber and the structure of a reference probe is identical with that of the sensing probe excluding a silicon oil. In this study, we measured the modified optical powers of the light signals reflected from the temperature sensing probe placed inside of the water with a thermal variation from 5 to $70^{\circ}C$. Although the optical power of the reference probe was constant regardless of the temperature change, the optical power of the sensing probe decreased linearly as the temperature increased. As experimental results, the FOTS using a subtraction method showed a small difference (i.e., hysteresis) in its response due to heating and cooling. The reversibility and reproducibility of the FOTS were also evaluated.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.261-267
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• 2004

Current steel makers are trying to develop new manufacturing process to secure price competition and to improve productivity by testing a various kinds of rolling condition of several kinds of steel at TCM. Accordingly, Reverse Mill operation for Stainless steel is changing to TCM operation and furthermore, even general carbon steel and electric steel plate are requested to be worked at TCM simultaneously. By these changing of rolling condition, it become to be necessary to develop new water-soluble cold rolling oil that has a characteristics to be suitable for various working condition and in this report, we would like to mention lubrication condition to fulfill requested characteristics of each steels and development and applying result of multi-purpose water-soluble cold rolling oil which has such an lubrication property.

• Resources Recycling
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• v.21 no.5
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• pp.31-37
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• 2012

As a recovery of elemental silicon from the sludge of Si wafer process, a process of mechanical separation-chlorine roasting-electrolysis has been suggested. The silicon sludge consisted of Si, SiC, machine oil, and metallic impurities. The oil and metal impurities was removed by mechanical separation. The Si-SiC mixture was converted to silicon chloride by chlorine roasting at $1000^{\circ}C$ for 1 hr and the silicon chloride was dissolved into an ionic liquid of $[Bmpy]Tf_2N$ as an electrolyte. Cyclic voltammetry results showed an wide voltage window of pure $[Bmpy]Tf_2N$ and a reduction peak of elemental Si from $[Bmpy]Tf_2N$ dissolved $SiCl_4$ on Au electrode, respectively. The silicon deposits could be prepared on the Au electrode by the potentiostatic electrolysis of -1.9 V vs. Pt-QRE. The elemental silicon uniformly electrodeposited was confirmed by various analytical techniques including XRD, FE-SEM with EDS, and XPS. Any impurity was not detected except trace oxygen contaminated during handling for analysis.