• Title/Summary/Keyword: Disintegration

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Disintegration and Spreading Behavior of the Spray emanating from a Liquid-thruster Injector (액체추력기 인젝터로부터 발생하는 분무의 분열 및 확산 거동)

  • Kim, Jin-Seok;Jung, Hun;Kim, Jeong-Soo;Kim, Sung-Cho;Park, Jeong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.11a
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    • pp.113-116
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    • 2008
  • Pseudo-3D Spatial distribution of spray droplets is investigated by using Dual-mode Phase Doppler Anemometry (DPDA) in order to examine the disintegration and spreading behavior of spray exiting from liquid-thruster injector. Spray injected from nozzle orifice with length-to-diameter ratio $(L/d_o)$ of 1.67 and at the injection pressure of 27.6 bar is aligned to the vertical. Vertical and horizontal mean velocities of droplets, Arithmetic Mean Diameter (AMD), Sauter Mean Diameter (SMD), and volumetric flux decrease as droplets travel from center/upstream toward outer region/downstream of spray.

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On-Site Conservation of the Underwater Objects Excavated (해저 발굴유물의 현장 보존처리)

  • Moon, Whan-Suk;Kim, Byung-Keun;Yang, Soon-Seok
    • 보존과학연구
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    • s.25
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    • pp.133-150
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    • 2004
  • Once the object has been excavated at underwater condition, it should be subjected to condition that may cause its deterioration. Therefore, it is important that the object immediately keeps stable environment. It means that the object was excavated at underwater and it exposed the deterioration condition, as soon as possible it was not dried on surface, especially metallic and organic material. Iron objects is particularly notorious for rapid disintegration that it kept wet or stored in a stable environment. Ceramics, glass and stone were handled carefully that it prevented physical damage by mishandling. Organic materials of wood, leather, rope, bone must not be allowed to dry out because the creaking, shrinking and warping are well known disintegration. Therefore objects is basis of keeping stable condition in on-site and then it will have to pass through a detailed conservation process in the laboratory.

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Drying Characteristics of Rotary Dryer with Disintegrator (교반기를 부착한 회전건조기의 건조특성)

  • Chun, W.P.;Lee, K.W.;Park, K.H.;Lee, K.J.;Kim, D.K.;Kim, H.S.
    • Proceedings of the KSME Conference
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    • 2001.06d
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    • pp.133-138
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    • 2001
  • In this paper, we have investigated the drying characteristics of waste sludge in a rotary dryer equipped with disintegration device. The sludge samples($moisture\;contents\;:\;70{\sim}85%\;W.B.$) used in the experiment were mainly a soybean and an alcohol fermentation sludges in food industry, or sewage sludge. It was studied by measuring the change of moisture contents that the shaft speed($operating\;range\;:\;100{\sim}250rpm$) affected on the drying rate and the particle size distribution of the dried solid. The dried granular products of the diameter of 1 to 5mm are obtained from sludge materials. In the results, as the increased of shaft speed, the particle size and the moisture contents of dried solid was decreased, and the retention time was increased.

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Feasibility Study of Dry Forming with Dry Forming Mould (원주형 건식초지기를 이용한 건식초지 가능성 평가)

  • Kim, Jong-Min;Lee, Hak-Lae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.41 no.1
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    • pp.9-16
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    • 2009
  • Cylindrical dry forming mould was developed to carry out a feasibility study of dry forming of papers. The effect of disintegration, forming, humidification and pressing on dry formed papers was examined. Dry disintegrated fibers showed the similar fiber length distribution to wet disintegrated fibers, but they showed distorsion and damaged appearance on the surface. Process parameters required to form a uniform fiber pad was investigated. A proper screening and air dispersion method was selected that gives proper formation. Humidification and pressing conditions were examined to get a good dry formed papers in dry forming. Results showed that dry forming method can be used to make a sheets with reasonable formation and properties.

Transient Breakup Phenomena of Initial Spray from High-Pressure Swirl Injector (와류형 고압인젝터의 초기분무의 분열 과도현상)

  • Choi, Dong-Seok;Kim, Duck-Jool;Ko, Chang-Kwon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.8
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    • pp.1132-1140
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    • 1998
  • The disintegration process of initial spray from high-pressure swirl injector was investigated at different injection pressures. The transient breakup phenomena that were difficult to observe at high injection pressure were easily observed at the low injection pressure of 0.4MPa. The effect of fuel remained inside a nozzle hole volume on the penetration of initial spray was also investigated. The disintegration process of initial spray could be classified four regions: the formation of mushroom shape, the first collision, the second collision, and the development of spray, The liquid film of cup shape was particularly found in the second collision region, and the growth ratio of its length and width at low and high injection pressures were compared.

A Study on Mosaic Pattern in Modern Costume (현대복식에 나타난 모자이크풍 패턴에 관한 연구)

  • 남윤숙;김복희
    • Journal of the Korean Society of Costume
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    • v.51 no.2
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    • pp.43-52
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    • 2001
  • The purpose of this research is to study the aesthetic character of a mosaic which is expressed in the Modern Costume. The methods of the research were by literature and it was mainly done with reference to master's theses, doctor's theses, separate volumes, periodicals, domestic and overseas fashion magazines and internet on the subject. The result of the research appears as rhythm, exoticism, abstraction, mystery, recreation by disintegration. First, rhythm appears in a sense of free rhythm with the method of arranging motives and the kinds of materials varying. Second, exoticism gives impression with such motives as Oriental designs, African designs and the geometric designs of nature occupying the surface. Third, abstraction displays motives such as unrealistic fashion. Fourth, mystery gives a cyber-related impression with the help of such scientific materials as fluorescent plastics, metal and glass. Fifth, recreation pelves an aesthetic impression by reorganizing the costume with the disintegration and transformation of Industrial materials such as plastics, metal and glass, etc. based on their unique colors and quality.

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Development of Fast Dissolving Tablet Containing Herb Extract by Freeze-Drying Technique

  • Kim, Jae-Il;Choi, Hoo-Kyun
    • Journal of Pharmaceutical Investigation
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    • v.40 no.3
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    • pp.161-166
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    • 2010
  • A fast dissolving tablet was developed using the freeze-drying technique. Hyeonggaeyeongyotang was selected as a model oriental medicine. Formulation and processing parameters were studied to obtain freeze-dried tablet with high drug loading, good palatability, and fast disintegration time. $Kollidon^{(R)}$ CLM served as both matrix former and taste masking agent. Ethanol used as co-solvent, decreased the disintegration time of tablet. Aspartame was employed to impart better taste. Drying condition was found to have a major effect in the morphology of the tablets. Freeze-drying process was optimized to decrease the processing time and improve the appearance of the tablets.

Effect of Hydrophobic Excipients on the Properties of Fast Disintegrating Tablets

  • Jeong, Seong-Hoon;Park, Ki-Nam
    • Journal of Pharmaceutical Investigation
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    • v.38 no.5
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    • pp.303-311
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    • 2008
  • Highly hydrophobic lubricants including magnesium stearate may hinder water penetration into the tablet core resulting in delayed disintegration of fast disintegrating tablets. Alternative lubricants with equivalent lubricating properties may need to be incorporated into the tablet formulations. Sodium stearyl fumarate, glyceryl behenate and polyethylene glycol were evaluated regarding the tablet ejection energy, mechanical strength and disintegration time using Texture analyzer (TA). Resulting tablets were also compared with different particle sizes of granules and various compression forces. Among the tested lubricants, sodium stearyl fumarate was less sensitive to mixing time and also showed better or competitive tablet properties. During the experiments, TA was found to be very useful tool to investigate the tablet properties.

The Experimental Study of Liquid Phase Mixing Mechanism of Split Triplet Impinging Spray (분리 충돌형 분사기의 액상 혼합 메커니즘에 관한 실험적 고찰)

  • 이성웅;조용호;윤웅섭
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2002.04a
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    • pp.18-23
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    • 2002
  • Liquid phase mixing of impinging injector is a resultant byproduct from the momentum exchange between a pair of impinging jets and penetration of opponent jet. Principal aim of the present study is revealing the liquid phase mixing mechanism of split triplet impinging injection sprays, and thus extending our understanding on this particular injection element. Overall mixing extent is estimated from patternation tests by the use of purified tap water and kerosene to simulate the real propellant components, respectively, and with the liquid jet momentum ratio, a controlling mixing parameter, in the range of 0.5 to 6.0. Emphasis is placed on the effect of liquid sheet superposition and disintegration, and the results with detailed spray visualization revealed the fact that superposed liquid sheet disintegration is the main pathway of liquid phase mixing of split triplet impinging injector to yield enhanced mixing qualities.

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Studies on the Effect of Microfine Cellulose upon the Preparation of Prednisolone Tablets by Direct Compression Method (직타법(直打法)에 의(依)한 Prednisolone 정제(錠劑)의 제조(製造)에 있어서 Microfine Cellulose가 미치는 영향(影響)에 관(關)한 연구(硏究))

  • Ok, Su-Jung;Yong, Jae-Ick
    • Journal of Pharmaceutical Investigation
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    • v.5 no.3
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    • pp.58-65
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    • 1975
  • In the preparation of prednisolone tablets, when microfine cellulose$(Elcema^{\circledR})$ was used as diluents, stability and physical characteristics of prednisolone tablets are as follows; 1. Weight of the plain $Elcema^{\circledR}$ tablets increased by 75% of relative humidity and hardness was weakend, but the temperature $(60^{\circ}C)$ caused no change of thickness and decreased the weight and hardness. 2. In experimental tableting of prednisolone tablets, the addition of $Elcema^{\circledR}$ caused no difficulty in direct compression method, and the shortening of the disintegration time and increase of the hardness were satisfactory. 3. Dissolution rate test exhibited the result similiar to disintegration test. 4. In the comparison test of $Elcema^{\circledR}$ and $Avicel^{\circledR}$ as adjuvants the physical constants of prednisolone tablets showed nearly a similar tendency.

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