• 제목/요약/키워드: Ice Freezing

검색결과 270건 처리시간 0.024초

개 정액의 정제화동결법과 Straw 동결법에 관한 비교실험 (A Comparison between Pellet and Straw Methods in Canine Semen Freezing)

  • 이정원;김희은;김남수;최인혁
    • 한국임상수의학회지
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    • 제8권2호
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    • pp.183-190
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    • 1991
  • Pellet and straw methods in canine semen freezing are compared with respect to motility, viability and acrosome demage of sperm during each of the two major processing steps, to prior-freezing and to frozen-thawing. Senen was extended with a tris-buffered egg yolk contained 4% glycero1 Pellet freezing in the hole of dry ice and straw freezing on the surface of liquid nitrogen were carried out, respectively. The frozen semen 10 days after storage in liquid nitrogen container. wao thawed. In the comparison of two freezing methods, the straw freezing method with 42.7% in motility. 49.2% in viability and 0.186 acrosome score after thawing seems to be superior to the pellet freezing method with 31.2%, 34.5% and 0.314%, respectively. Sperm motility of processing step to frozen-thawing against decrease rate 12.67% to Prior freezing appeared of 33.84% and 49.37% in straw and pellet freezing and increase of 0.02 in acrsomal score to prior freezing appeared of 0.08 and 0.21 in straw and pellet freezing method to frozen-thawing

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도로 노면결빙 판정모델을 적용한 도로결빙 예측에 대한 연구 (A study on road ice prediction by applying road freezing evaluation model)

  • 임희섭;김상태
    • 한국응용과학기술학회지
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    • 제37권6호
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    • pp.1507-1516
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    • 2020
  • 본 연구는 도로 노면결빙 판정 알고리즘을 적용하여 도로결빙 구간에 대한 시나리오를 분석하였다. 도로결빙 알고리즘 적용을 위해서, 도로 결빙에 대한 영향인자를 검토하고, 분석을 위해서 목감IC, 정릉터널, 성산대교, 염창교 등 4지점의 관측자료를 활용하였다. 관측소는 모두 고속화도로에 설치되어 있으며, 도로 결빙 특성 분석을 위하여 분류하였다. 도로 결빙 판정 알고리즘의 노면온도-노점온도 차가 3℃ 이하일 때 도로결빙 발생 구간을 확인하고 결빙 구간의 노면상태와 수막두께 변화를 통해 도로 결빙 판정을 도출하였다.

동심원관 환상공간내의 완전히 발달된 층류유동에서 물의 결빙현상에 대한 해석 (Analysis of ice-formation phenomena for fully developed laminar water flow in concentric circular-tube annuli)

  • 서정세;노승탁
    • 대한기계학회논문집B
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    • 제21권11호
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    • pp.1552-1561
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    • 1997
  • In this numerical study, it is investigated for the ice-formation phenomena for water flow in a concentric tube. The freezing layers of ice in both the inner and outer wall of a concentric tube are simultaneously considered. In the solution strategy, the complete set of governing equations in both the solid and liquid regions are resolved. Numerical results are obtained by varying the inner/outer wall temperatures and Reynolds number. The results show that the inner/outer wall temperatures have the great effect on the thickness of the solidification layer thereof. The shapes of ice layer in both the inner and outer wall can be expressed as a function of inverse Graetz number. As the wall temperature in inner or outer tube decreases, the heat transfer coefficients in both inner and outer ice layer surfaces increase absolutely.

Evaluation of Thermal Hysteresis Activity of Ice-binding Proteins Using Ice-etching and Molecular Docking

  • Nugroho, Wahyu Sri Kunto;Wu, Sangwook;Kim, Hak Jun
    • 대한화학회지
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    • 제62권2호
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    • pp.106-112
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    • 2018
  • Ice-binding proteins have an affinity for ice. They create a gap between the melting and freezing points by inhibiting the growth of ice, known as thermal hysteresis (TH). Interestingly, moderately active LeIBP and hyperactive FfIBP are almost identical in primary and tertiary structures, but differ in TH activity. The TH of FfIBP is tenfold higher than that of LeIBP, due to a subtle difference in their ice-binding motifs. To further evaluate the difference in TH, the interactions were investigated by ice-etching and molecular docking. Ice-etching showed that FfIBP binds to the primary and secondary prism, pyramidal, and basal planes; previously, LeIBP was found to bind to the basal and primary prism planes. Docking analysis using shape complementarity (Sc) showed that the hyperactive FfIBP had higher Sc values for all four ice planes than LeIBP, which is comparable with TH. Docking can be used to describe the hyperactivity of IBPs.

선박용 제빙장치의 개발을 위한 해수동결거동에 관한 연구 (A study on sea-water freezing behavior for ice maker for fishing boat)

  • 최영규;김정식;김경근;오철
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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    • pp.233-238
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    • 2005
  • According to change of flow around a circular tube for freezing, measured a variety of salinity of frozen layer. This study was experimentally performed to investigate freezing behavior of sea water along a vertical cooled a circular tube with bubbly flow. The experiments were carried out for a variety of parameter, such as air-bubble method, cooled -tube temperature and air-flow rate. It was found that the experimental parameters gave a great influence on the freezing rate and the salinity of the frozen layer.

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충격공진시험을 이용한 노상토의 동결.융해시 강성도 변화 측정 (Stiffness change measurement for subgrade soils at freezing and thawing using impact resonance test)

  • 이재환;권기철
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.686-691
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    • 2009
  • Damage due to frost action in pavement structure system is creating either frost heave or stiffness-weakening of subgrade soil follow melting. The formation of ice lenses requires a frost-susceptible soil, freezing temperatures, and continuous water supply. Eliminating one of these conditions suffices to significantly reduce the intensity of frost action. It is important to know characteristics of subgrade soil in frost susceptibility or decide degree of freezing permission. Also, study on the stiffness variation of subgrade soil during freezing and thawing cycle is very important. In this study, Impact resonance test for subgrade soil at freezing and thawing confirms that is applied for.

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Effects of Artificial Supercooling Followed by Slow Freezing on the Microstructure and Qualities of Pork Loin

  • Kim, Yiseul;Hong, Geun-Pyo
    • 한국축산식품학회지
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    • 제36권5호
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    • pp.650-655
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    • 2016
  • This study investigated the effects of artificial supercooling followed by still air freezing (SSF) on the qualities of pork loin. The qualities of pork frozen by SSF were compared with the fresh control (CT, stored at 4℃ for 24 h), slow freezing (SAF, still air freezing) and rapid freezing (EIF, ethanol immersion freezing) treatments. Compared with no supercooling phenomena of SAF and EIF, the extent of supercooling obtained by SSF treatment was 1.4℃. Despite that SSF was conducted with the same method with SAF, application of artificial supercooling accelerated the phase transition (traverse from -0.6℃ to -5℃) from 3.07 h (SAF) to 2.23 h (SSF). The observation of a microstructure indicated that the SSF prevented tissue damage caused by ice crystallization and maintained the structural integrity. The estimated quality parameters reflected that SSF exhibited superior meat quality compared with slow freezing (SAF). SSF showed better water-holding capacity (lower thawing loss, cooking loss and expressible moisture) and tenderness than SAF, and these quality parameters of SSF were not significantly different with ultra-fast freezing treatment (EIF). Consequently, the results demonstrated that the generation of supercooling followed by conventional freezing potentially had the advantage of minimizing the quality deterioration caused by the slow freezing of meat.

Characteristic of the Formation and Adhesion of Ice on a Cooling Surface by a Stirring Aqueous Solution

  • Kang, Chae-Dong;Seung, Hyun;Hong, Hi-Ki
    • International Journal of Air-Conditioning and Refrigeration
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    • 제14권3호
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    • pp.110-117
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    • 2006
  • Ice adhesion or cohesion leads to the decrease of the performance of ice making system, especially to dynamic type ice thermal storage system (DISS) which mainly forms ice from the flow of an aqueous solution. The ice adhesion is influenced by various parameters associated with operating or geometric condition. In this study, the influence on an adhesion of ice to the characteristic of cooling surface and to composition of an aqueous solution was fundamentally observed by using batch type cooling device,. a beaker. Three patterns of solution in each beaker were cooled with brine. Moreover, the characteristic of cooling surface on each beaker was distinguished to coating materials. Stirring power as a degree of the ice adhesion was measured. The stirring power to cooling heat transfer rate in each beaker was compared. As a result, the lowest stirring power of 8.9 W with non-adhesion of ice, was shown in the case of the aqueous solution of EG(4) + PG(1.5) + 1,6HD(1.5). in PE coating beaker.

EG/AD 모형빙 정도 향상을 위한 콜드룸에서의 생성기법 및 계측기법 연구 (An Experimental Study on Generation and Measurement Method of EG/AD Model Ice at Cold Room for Improvement of Its Properties)

  • 조성락;정성엽;하정석;강국진
    • 대한조선학회논문집
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    • 제50권6호
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    • pp.414-420
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    • 2013
  • Generation and measurement methods of EG/AD model ice, which is used in KIOST ice model basin are investigated for improvement of its properties. Temperature of seed water, air temperature in the freezing phase and the target air temperature in the tempering phase were changed in the cold room, and the properties of model ice was measured in this conditions. We also verified a conventional measuring method of flexural strength of model ice caused a little measuring error in cold room, so that we suggested a new measuring method that must be used higher supports than double the thickness of the model ice. In this study, we improved the generation and measurement technique of EG/AD model ice, and the developed procedure at cold room can be applied to the KIOST ice model basin.

Review of Ice Characteristics in Ship-Iceberg Collisions

  • Lee, Tak-Kee;Park, Hyun-Jin
    • 한국해양공학회지
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    • 제35권5호
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    • pp.369-381
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    • 2021
  • The International Ice Patrol (IIP) was established after the Titanic collided with an iceberg off the eastern coast of Canada in 1912 and sank, killing more than 1,500 people. Recently, the IIP has analyzed satellite images and provided safe operation information to vessels by tracking the occurrence and movement of icebergs. A large number of recent arctic studies mainly deal with sea ice formed by freezing seawater related to sea routes and resource development. The iceberg that collided with the Titanic was land-based ice that dislodged from a glacier and fell into the sea. The properties of these two types of ice are different. In addition, vessels operating in ice-covered waters such as the Arctic sea have an ice-breaking function or minimum ice-strengthened functions. Ships operating on transatlantic routes including the eastern coast of Canada do not necessarily require ice-strengthened functions. Hundreds to thousands of icebergs are discovered each year near the area where the Titanic sank. In this study, the status of ship-iceberg collision accidents was investigated to provide useful information to researchers, and the physical and mechanical characteristics of icebergs were investigated and summarized.