• Title/Summary/Keyword: freezing days

Search Result 280, Processing Time 0.025 seconds

Effects of Freezing Period and Chilling Process after Thawing on Physicochemical Properties and Palatability of Loin from Jeju Island Reared Crossbred Black Pigs (동결 기간 및 해동 후 냉장이 제주 흑돼지고기의 물리화학적, 기호적 품질에 미치는 영향)

  • Moon, Yoon-Hee
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.20 no.4
    • /
    • pp.560-566
    • /
    • 2010
  • In this study, the effects of the chilling process after thawing on pork quality were investigated by comparing the physiochemical properties and palatability of the samples just after thawing(0-TP) and the other chilled at $2^{\circ}C$ for two days after thawing (2-TP). The samples used for this study were obtained from vacuum packaged frozen loin from crossbred black pigs reared on Jeju island, and frozen at $-20^{\circ}C$ for 1 month and 12 months, and then thawing them at $4^{\circ}C$ for 20 hours. In the case of loin that was thawed after freezing for 1 month, 2-TP showed a higher water holding capacity and myofibril fragmentation index, lower hardness and chewiness, as well as better juiciness and palatability than 0-TP. However, effects of chilling after thawing were not significant in the case of loin that had been frozen for 12 months.

The Compressive Strength and Durability Properties of Polypropylene Fiber Reinforced EVA Concrete (폴리프로필렌 섬유 보강 EVA 콘크리트의 압축강도 및 내구성)

  • Nam, Ki Sung;Sung, Chan Yong
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.57 no.4
    • /
    • pp.11-19
    • /
    • 2015
  • The important properties of EVA (ethylene vinyl acetate) redispersible polymer was waterproof, densification of internal pore space of concrete and ball bearing and micro filler. Also, the significant role of polypropylene(PP) fiber was crack control and blockade of movement for deterioration factors. The most studies for EVA were limited in the field of mortar and PP fiber reinforced concrete had been studied in the state of being restricted unit water content, rich mix and mixing much of the fiber without considering construction site. Therefore, the control mix design were applied in ready mixed concrete using 10 % fly ash of total cement weight used in batch plant. On the basis of control mix design, EVA contents ranging from 0 % to 10 % of total cement weight and PP fiber contents ranging from 0 % to 0.5 % of EVA concrete volume were used in the mix designs. The results showed the maximum compressive strength value was measured at EVA 5.0 % and PP fiber 0.1 %, the minimum water absorption ratio was at EVA 10 % and PP fiber 0 %, the durability factor for freezing and thawing resistance was at EVA 5.0 % and PP fiber 0.3 % and the minimum weight reduction ratio of resistance to sulfuric acid attack was at EVA 10 % and PP fiber 0.5 % after curing age 42days. Meanwhile, From these results, PP fiber reinforced EVA concrete would be very benefit, if each optimal mix types were used in hydraulic structures, underground utilities and agricultural structures.

Unconfined compressive strength and freeze-thaw resistance of sand modified with sludge ash and polypropylene fiber

  • Gullu, Hamza;Fedakar, Halil I.
    • Geomechanics and Engineering
    • /
    • v.13 no.1
    • /
    • pp.25-41
    • /
    • 2017
  • In recent years, the amount of sludge ash (SA) has considerably increased due to rapid urbanization and population growth. In addition, its storage in landfills induces environmental pollution and health problems. Therefore, its disposal in an environmentally friendly way has become more important. The main goal of this study is to investigate the reusability of sludge ash as an additive with polypropylene fiber (PF) to stabilize marginal sand based on the compressive strength performances from UCS tests. For this purpose, a series of UCS tests was conducted. Throughout the experimental study, the used inclusion rates were 10, 15, 20 and 30% for sludge ash and 0, 0.5 and 1% for polypropylene fiber by total dry weight of the sand+sludge ash mixture and the prepared samples were cured for 7 and 14 days prior to the testing. Freezing and thawing resistance of the mixture including 10% sludge ash and 0, 0.5 and 1% polypropylene fiber was also examined. On the basis of UCS testing results, it is said that sludge ash inclusion remarkably enhances UCS performance of sand. Moreover, the addition of polypropylene fiber to the admixtures including sand and sludge ash significantly improves their stress-strain characteristics and post-peak strength loss as well as UCS. As a result of this paper, it is suggested that sludge ash be successfully reused with polypropylene fiber for stabilizing sand in soil stabilization applications. It is also believed that the findings of this study will contribute to some environmental concerns such as the disposal problem of sludge ash, recycling, sustainability, environmental pollution, etc. as well as the cost of an engineering project.

Durability Properties of High Volume Blast Furnace Slag Concrete for Application in Nuclear Power Plants (고로슬래그 다량치환 콘크리트의 원전 콘크리트 적용을 위한 내구성능 평가)

  • Seo, Eun-A;Lee, Jang-Hwa;Lee, Ho-Jea;Kim, Do-Gyeum
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.5 no.1
    • /
    • pp.45-52
    • /
    • 2017
  • This study evaluated the durability of nuclear power plant concrete. The main parameters were the water-to-binder ratio and admixture type. The results revealed that high-volume ground granulated blast-furnace slag(GGBS) concrete had lower initial strength, while the strength reached higher after 28 days. On the other hand, the initial strength of fly ash blended concrete was high, but the long-term strength of the robbery was low. The measured durability of GGBS blended concrete was found to be better than that of the existing concrete mix for use in the construction of nuclear power plants. Especially, the GGBS blended concrete was more durable than the fly ash blended concrete in terms of chloride attack, carbonation resistivity and freezing-thawing durability in low compressive strength. The effects of concrete compressive strength according to gamma rays were minor.

Effects of Curcumin from Turmeric Supplementation in Freezing Buffer on Sperm Motilities and Reactive Oxygen Species Generation (동결보존액에 울금에서 추출한 Curcumin의 첨가가 정자의 운동성과 활성산소 생성에 미치는 영향)

  • Lee, Eun-Joo;Kim, Dae-Young
    • Journal of Embryo Transfer
    • /
    • v.32 no.3
    • /
    • pp.249-255
    • /
    • 2017
  • In this experiment, we determined the effect of curcumin supplementation in freezing buffer for miniature pig sperm cryopreservation. Each ejaculate was diluted with modified Modena B extender and mixed with lactose-egg yolk (LEY extender, 80% v/v lactose solution [310 mM], 20% v/v egg yolk, and $100{\mu}g/mL$ kanamycin sulfate) and LEY-glycerol Orvus ES Paste (LEYGO, 89.5% v/v LEY, 5% v/v glycerol, 1.5% v/v Orvus ES Paste), 100 mM trehalose supplemented with 0, 10, 50, 100, and $500{\mu}M$ of curcumin from turmeric, respectively. Following equilibration, the 0.5 mL French straws were frozen and plunged into $LN_2$ tank for 7 days at least. Sperm parameter and oxidative byproducts were determined by the computer assisted sperm motility analysis (CASA) and fluorescence-activated cell sorting (FACS) as compared with each groups. Supplementation of curcumin had no effect on sperm motility, progressive motility and curvilinear velocity. However, average-path velocity and straight-line velocity were significantly higher in $10{\mu}M$ curcumin group ($100.9{\pm}8.8{\mu}m/s$, $61.7{\pm}2.9{\mu}m/s$, respectively) than control group ($77.8{\pm}3.9{\mu}m/s$, $46.4{\pm}3.0{\mu}m/s$, respectively) (p < 0.05). In addition, the level of the O2 radical and H2O2 were comparatively decreased in curcumin groups by evaluation of ethidium and DCF fluorescence. According to the results, curcumin can improve sperm kinetic variables and alleviate ROS induced cryoinjury to pig sperm.

An Experimental Study on Concrete with Che-Ju Aggregates (제주도 골재를 사용한 콘크리트의 실험적 연구)

  • 최광일;김진춘;성용환;김상용
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1995.04a
    • /
    • pp.148-153
    • /
    • 1995
  • In this report, the physical and chemical properties of Che-ju aggregates were stedued, and the properties of concrete using 5 types combinations of Che-ju aggreagtes were compared with those of concrete using Dag-jeon area aggreagtes. As a result of the properties of Che-ju aggregates are very different with Dae-jeon area aggregates in many aspects. Especially, entrained air content of aggregate is over 1.5% so that the freezing & thawing resistance of concrete was caused in decrease. And the texture properties of Che-ju aggregates and a little content of the entrained air in mortar increase bonding stress between mortar and aggregate, as a result in improving the compressive strength of concrete. Meanwhile, the relationship between cement water ratio(C/W) and 28days compressive strength of concrete(F28) is derived from the stastical regression using experimental data as $F_{28} = -99 + 276 *($(C/W), so this eqation is useful for mix-design of concrete in Che-ju area.

  • PDF

Intelligence Transportation Safety Information System

  • Hong, YouSik;Park, Chun Kwan;Cho, Seongsoo;Hong, Suck-Joo
    • International Journal of Internet, Broadcasting and Communication
    • /
    • v.6 no.2
    • /
    • pp.20-24
    • /
    • 2014
  • These days the large-scale car accidents have often been occurred by overspeeding in disregard of sharp curve, foggy and freezing regions. This paper has proposed the algorithm to calculate the safety speed in real time that can protect the car accidents under these weather and road conditions using Fuzzy reasoning theory. Under raining and snowing, drivers have to slow down the traffic safety speed by 1/3 of the traffic safety speed indicated on the existing speed sign plate based on their decision. So it is difficult to calculate and then observe the safety speed. This paper has performed the simulation that provides the deivers with the optimal safety speed considering the road and weather conditions in real time to improve these problems. We have proved this method can improve more 25% than the existing one.

Evaluation on Compressive Strength of Mortar and Concrete at Early Age Using Variable Cement and Self-heating Binder (시멘트 산지 및 자기발열분체 사용에 따른 모르타르 및 콘크리트의 저온에서의 압축강도성능 평가)

  • Hong, Seok-Beom;Kim, Woo-Jae;Yoo, Jo-Hyeong
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2016.10a
    • /
    • pp.152-153
    • /
    • 2016
  • In this research, we evaluate the performance for preventing frost damage at early age of mortar using variable cement and self-heating binder. Purpose of final research is preventing freezing and thawing by making the compressive strength 5MPa in 3days below zero temperature without heat curing. We compare the compressive strength of mortar and concrete using variable cements and self-heating binder in low temperature.

  • PDF

Properties of Porous Polymer Concrete Reinforced Polypropylene Fiber (폴리프로필렌섬유보강 포러스 폴리머 콘크리트의 특성)

  • Kim, Young-Ik;Sung, Chan-Yong
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.11a
    • /
    • pp.723-726
    • /
    • 2004
  • Porous polymer concrete can be applied to roads, sidewalks, river embankment, drain pipes, conduits, retaining walls, yards, parking lots, plazas, interlocking blocks, etc. This study is to examine a content ratio of polypropylene fiber to improve bending strength, impact resistance and freezing and thawing rssistance of porous polymer concrete. Also, this study is performed to develop the porous polymer concrete using recycled coarse aggregate and blast furnace slag for application of structures needed permeability. At 7 days of curing, compressive strength, flexural strength, water permeability and flexural load are in the ragge of $17\~21MPa,\;5\~7MPa,\;4.1\times10^{-2}\~7.7\times10^{-2}cm/s$, respectively. It is concluded that the recycled aggregate can be used in the porous polymer concretes.

  • PDF

Effect of Use of SPS Agar and SGS Broth and Storage of Specimen on the Isolation of Vibrio vulnificus (Vibrio vulnificus 분리율에 대한 SPS Agar와 SGP Broth의 사용 및 검체 저장의 영향)

  • Chong, Yun-Sop;Lee, Samuel Y.;Kim, Shin-Moo
    • The Journal of the Korean Society for Microbiology
    • /
    • v.22 no.2
    • /
    • pp.103-108
    • /
    • 1987
  • Vibrio vulnificus septicemia is nor-rare diease in Korea. Carriage rate of the orgaism by shellfish is not well known. In this study performance of SPS agar and SGP broth and effect of storage of specimen in the isolaton was determined using the shellfish specimens collected from the coast and market of Koonsan city. Isolation rate was similar with TCBS and with SPS, but the rate became much highher after enrichment in SGP broth. 80% of oyster speimes were positve when inoculated immediately, but the rate dropped rapidly after storage of specimens at freezing temperature for sometime. All of the isolates fermented lactose in 2 days. A few isolates were not identfiable with API 20E system, because of acid prduction from melibiose. Serover 04 was the frequent isolates.

  • PDF