• 제목/요약/키워드: Freezing Solution

검색결과 273건 처리시간 0.027초

냉각법 및 영상 처리기법을 이용한 서브마이크론 정전분무 액적의 크기분포 측정 (Measurement of Size Distributions of Submicron Electrosprays Using a Freezing Method and an Image Processing Technique)

  • 구본기;김상수;김유동
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.100-106
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    • 2001
  • The size distributions of electrospray droplets from the Taylor cone in cone-jet mode are directly measured by using a freezing method and a transmission electron microscope (TEM) image processing technique. These results are compared with the data obtained by an aerodynamic size spectrometer (TSI Aerosizer DSP). The use of glycerol seeded with NaI and a freezing method make it possible to sample droplets with their original sizes preserved. Since pictures of droplets are taken with TEM with very low vapor pressure of the solution, evaporation is suppressed by freezing. For liquid flow rates below 1 nl/sec, the measured droplet diameters by the TEM image processing technique and the aerosizer are in the range of 0.25 to $0.32{\mu}m$ and 0.30 to $0.40{\mu}m$, respectively. Comparing the TEM data with the aerosizer measurements, it has been revealed that the TEM image processing technique can afford more accurate values of droplet size distributions in the submicron range of 0.1 to $0.4{\mu}m$.

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생쥐 체외수정난의 초급속동결 및 이식에 관한 연구 III. 생쥐 체외수정난의 초급속동결-융해란의 이식에 관하여 (Studies on Transfer of In vitro Fertilized Mouse Embryos Following Ultrarapid Freezing III. A Study on Transfer In Vitro Fertilization Mouse Embryos Following Ultrarapid Freezing-Thawing)

  • 장규태;민관식;오석두;강대진;윤창현
    • 한국가축번식학회지
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    • 제16권3호
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    • pp.217-224
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    • 1992
  • These studies were carried out ot investigate on the transferred embryo development following ultrarapid frozen for 8-cell and morula of in vitro fertilization mouse embryos. The post-thaw embryo survival was evaluated and compared by cell stage of embryos and by equilibration time before ultrarapid freezing. The results obatined were summerized as follows: 1. The effects of equilibration time of 3 vs. 6 minutes before ultrarapid freezing and after thawing on the morphological survival and the viability of 8-cell and morulas embryos were not significant. 2. When the ultrarapid frozen-thawed 32 eight-cell and 33 morula embryos, and 30 fresh blastocysts were transferred to pseudopregnant recipient mice, the number of normal offsprings produced were 9(28.1%), 14(42.4%) and 18(60.0%), respectively. From the above resutls, it was concluded that the optimal conditions of pH osmolality of the media for mouse IVF and embryo culture, and the period of sperm preincubation might be 7.1, 310 mOsm and 120 min., respectively,a nd somewhat high conception rate might be resulted from transfer of frozen embryos of morula stage and fresh embryos of blastocyst stage.

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Mesoporous 막 제조를 위한 급냉법에 의한 역 열유도상전이공정 (Formation of Mesoporous Membrane by Reverse Thermally induced Phase Separation (RTIPS) Process Using Flash Freezing)

  • 염충균;김지원;박희영;박성은;이기윤;이규호
    • 멤브레인
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    • 제31권1호
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    • pp.67-79
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    • 2021
  • 급냉법에 의한 역 열유도상전이(RTIPS) 공정을 사용하여 mesoporous polystyrene (PS), polyethersulfone (PES) 막을 제조하였다. 급냉법에 의한 RTIPS 공정은 급냉 및 승온 시 도포 용액 내 용매 분자들의 결정 생성 및 성장을 통해 나노 규모의 상전이를 야기시켜 mesoporous 기공들을 형성된다. 시차주사열량계(TA: DSC) 사용해 측정된 사용 용매 dimethylformamide (DMF)와 여러 고분자 함량의 고분자용액들에 대한 엔탈피 변화와 주사현미경(SEM)을 사용하여 측정한 고분자함량에 따른 제조된 막 구조, 그리고 비표면적 분석기(BET) 사용하여 측정한 고분자 함량에 따라 제조된 막의 기공크기분포 및 표준편차 분석을 통해 RTIPS 공정 시 상전이 거동을 살펴보았다

Is optimal cutting temperature compound essential embedding solution treatment to cryo-sectioning of brain tissue?

  • Baek, Hye Kyung;Song, Ji Ae;Yi, Sun Shin
    • 대한수의학회지
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    • 제56권2호
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    • pp.85-89
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    • 2016
  • We tested a set of conditions for obtaining optimal tissue quality in preparation for histology in samples of mouse brain. C57BL/6J mice were sacrificed and perfused with 4% paraformaldehyde, after which the brains were removed and dehydrated in 30% sucrose solution. The brains were then divided into four groups according to freezing temperature and usage of optimal cutting temperature (OCT) compound. Next, we stained the sectioned brain tissues with Harris hematoxylin and eosin Y and immunohistochemistry was performed for doublecortin. The best quality tissue was obtained at $-25^{\circ}C$ and by not embedding with the OCT compound. When frozen at $-25^{\circ}C$, the embedded tissue was significantly damaged by crystals, while at $-80^{\circ}C$ there were no meaningful differences between qualities of embedded- and non-embedded tissues. Overall, we identified a set of conditions to obtain quality frozen brain sections. Our developed protocol will help resolve matters associated with damage caused to sectioned brain tissue by crystal formation during freezing.

초그속동결에 있어서 Vitrification Solution 개발과 FDA 생사판정이 수정란의 배양과 이식후 착상에 미치는 영향 I. Vitrification Solution내의 내동제 조합이 초급속동결 융해후 Mouse Morulae의 생존율에 미치는 영향 (Effects of the Improvement of Vitrification Solution and FDA-test on the Embryo Survival and Conception Rate by Ultrarapid Freezing I. Effects of the Combination of Cryoprotectants in Vitrification Solution on the Survival of Frozen-Thawed Mouse Embryos)

  • 김종규;강민수;고경래;양병철
    • 한국가축번식학회지
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    • 제16권3호
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    • pp.269-276
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    • 1992
  • Studies were carried out to find the freezing media which gives no ice crystals in single(glycerol, ethylene glycol, dimethyl sulfoxide(DMSO)) and mixture solutions(glycerol+propylene glycol, glycerol+ethylene glycol) of permeable cryoprotectants in vitrification solution and to study effects of VS on the survival of vitrified mouse morulae. The results are summarized as follows: 1. In toxicity test of permeable cryoprotectants, 30% glycerol of single solution showed the highest FDA-score(4.1) in mouse morulae frozen compared among other single solutions. The FDA-score(4.1) of 30% glycerol was higher than 30% ethylene glycol(3.6) and DMSO(1.4( (P<0.05). 2. 20, 30 or 40% single solution of permeable cryoprotectants containing m-PBS with 10% sucrose and 20% BSA was not crystallized during cooling, but crystallized during warming. However, the 30% mixture solution of the two permeable cryoprotectants was not crystallized both during cooling and warming.3. When mouse morulae were frozen in 30% mixture solutions of two permeable cryoprotectants(glycerol and propylene glycol, glycerol and ethylene glycol), highest FDA-score(4.5) was obtained in a mixture solution of 20% glycerol and 10% ethylene glycol(20G10E) than other 30% mixture solutions(10G20E, 15G15E, 20G10P, 15G15P, 10G20P) and there was significant difference between 20G10E and 10G20E(P<0.05).

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Enhancement in the Viability and Biosensing activity of Freeze-Dried Recombinant Bioluminescent Bacteria

  • Park, Sue-Hyung;Gu, Man-Bock
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제5권3호
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    • pp.202-206
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    • 2000
  • The genetically-engineered Escherichia coli strain, DPD2540, which contains a fabA:::luxCDAbefusion gene, gives a bioluminescent output when membrane fatty acid synthesis is needed. For more pactical application of this strain in the filed as biosensor, freezedrying was adopted. A 12% surcrose solution with Luria-Bertani (LB) broth, as determined by the viability after freeze-drying, was found to be most most effective composition for lyophilization solution among various compositions testitons tested. Rapid freezing with liquid nitrogen also gave the best viability after freeze-drying as compared to samples frozen at-7$0^{\circ}C$ and -2$0^{\circ}C$. The biosensing activities of the cells showed a greater sensitivity when the cells from the expontial phase were freeze-dried. Finally, the optimum temperature for use of the freeze-dried cells in the biodencor field was determined.

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Operation of Smart Refrigeration Logistics Center based on Cold Chain System

  • Cho, Gyu-Sung
    • Journal of Multimedia Information System
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    • 제5권4호
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    • pp.229-234
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    • 2018
  • This paper focuses on the frozen storage warehouse located in Busan area, and it is because Busan is the most dense area in Korea. Busan is a port city, and almost all of the frozen refrigerated cargo imported from abroad is concentrated. By taking advantage of its strength as a fishery industry as well as importing, Busan is building the largest international fishery logistics base in Northeast Asia and plays an important role in the export of refrigerated cargo is. Therefore, although the freezing and chilling facilities seem to be developed with the latest technology, the reality is not so. Most of them are functioning as a warehouse, that is, a storage function, and a considerable number of refrigerated warehouses are in a state of aging. Therefore, in this paper, the facility and function restructuring of the freezing storage warehouse have been set as a solution task, and the introduction of the cold chain system containing the latest smart technology has been proposed as a solution.

미니돼지 정액 동결 시 Methyl-Beta-Cyclodextrin (MBCD)이 냉각 충격과 막 콜레스테롤량에 미치는 영향 (Effects of Methyl-Beta-Cyclodextrin (MBCD) on Cold Shock and Membrane Cholesterol Quantity during the Freezing Process of Miniature Pig Spermatozoa)

  • 이성영;이용승;정희태;양부근;박춘근
    • Reproductive and Developmental Biology
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    • 제35권3호
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    • pp.265-271
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    • 2011
  • This study was undertaken to find out the effect of methyl-beta-cyclodextrin (MBCD) on cold shock and membrane cholesterol quantity of sperm during the freezing process in miniature pigs. For this study, semen ejaculated from PWG M-type miniature pig was diluted that freezing solution (with egg yolk group) and m-Modena B (without egg yolk group) treated with 0, 1, 5, 10 and 20 mM MBCD before freezing process. The diluted semen was monitored sperm ability at room temperature, after cooled until $5^{\circ}C$ and after forzen-thawed for cold shock test of spermatozoa. Also, membrane cholesterol of sperm was extracted by folch solution at the same time sperm ability was assessed for viability and acrosomal status. The membrane cholesterol quantity was measured by thin-layer chromatography (TLC) method. The result, viability and acrosome integrity in semen diluted without egg yolk groups were decreased at all temperature range by increasing of MBCD concentration. In particular, sperm of egg yolk group was showed that significantly higher viability and lower acrosome damage when treated with 5 mM MBCD (p<0.05). The results of TLC experiment, cholesterol amounts were increased with MBCD cocentration in egg yolk, and decreased with MBCD concentration in m-Modena B. In cryopreservation efficiency, there was no significant difference at viability, and acrosomal state of sperm in 5 mM MBCD concentration was significantly lower in acrosome damage than other groups (p<0.05). Therefore, the addition MBCD in egg yolk was protected spermatozoa from cold shock injury. This protective effect of MBCD may be due to addition of sperm membrane cholesterol.

과냉각을 동반한 동결과정의 수치해석 (Numerical Analysis for Cooling and Freezing Processes with Subcooling)

  • 윤정인;김재돌;김성규
    • 설비공학논문집
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    • 제8권4호
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    • pp.451-462
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    • 1996
  • In this study, which focuses on ice storage, a fundamental study in cooling and solidification was performed, including the interesting phenomena of density inversion, supercooling and dendritic ice. A numerical study was performed for natural convection and ice formation considering existence of subcooling and dendritic ice were analyzed numerically by using finite difference method and boundary fixing method. In the mesh, the solid fraction was introduced with adding as a term to the energy conservation equation. A flow in the dendrite was modelled as a flow in a porous medium, and the momentum conservation equation was modified to incorporate resistance forces involved in flows through porous media. A numerical solution of the time dependencies of dendrite area and dense ice front was successfully obtained, and the numerical results were good agreement with experimental results. Based on this methodology, a discussion was made of phenomena and characteristics of cooling and freezing processes under various conditions.

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칼슘이 뽕나무 뿌리의 발육과 가지의 내동성에 미치는 영향 (Effect of Calcium in Nutrient Solution on Root Development and Freezing Tolerance of Mulberry)

  • 류근섭;최영철
    • 한국잠사곤충학회지
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    • 제39권1호
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    • pp.12-16
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    • 1997
  • Effects of calcium on mulberry growth and freezing tolerance were examined by water culture. Calcium was supplied by folar spray with the levels of 0, 5, and 40 ppm. Muberry stems developed by 130 cm at Ca2+ 40ppm, 82 cm at Ca2+ 5 ppm and 23 cm at Ca2+ 0 ppm. Muberry roots also developed vigorously at Ca2+ 40 ppm, but did poorly at Ca2+ 5 ppm and changed to brown in color, and died becoming necrosis at Ca2+ 0 ppm. Content of calcium in leaves and barks were increased at Ca2+ 40 ppm compared with at Ca2+ 5 ppm. Total sugar, RNA, proline and phospholipid at Ca2+ 40 ppm were also more increased than those at Ca2+ 5 ppm. Mulberry stems grown at Ca2+ 40 ppm showed a sufficient tolerance at -10 for 24 hours while stems grown at Ca2+ 5 ppm did a weak tolerance at the same conditions.

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