• Title/Summary/Keyword: Temperature

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A COMPARATIVE EXPERIMENTAL STUDY ON THE SURFACE CHARACTERISTICS AND THE FITTNESS OF THE RESILIENT DENTURE LINES (탄성 의치상 이장재의 표면 특성 및 적합도에 관한 비교 실험 연구)

  • Lee, Soo-Back;Yoon, Chang-Keun
    • The Journal of Korean Academy of Prosthodontics
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    • v.25 no.1
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    • pp.137-154
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    • 1987
  • The purpose of this investigation was to determine the surface characteristics and the fittness of the resilienct denture lines. Firstly, 50 samples ($2.0{\times}4.0{\times}0.3cm$) of 4 resilient lining materials (Molloplast B, Coe Super Soft, Mollosil, Coe Soft) and one conventional acrylic resin (K-33) were processed according to manufacture's direction and examined the surface characteristics by use of surface profilometer and scanning electron microscopy. Secondly, 50 identical maxillary casts were made and 50 denture bases were pro cessed of 4 resilient liners and one conventional acrylic resin and they were stored in the room temperature water bath of 1 day, 1 week, 2 weeks, 3 weeks, 4 weeks and 6 weeks after processing. The original casts were cut away 1 cm from the posterior border, the dentures were seated, and the existing space was measured at seven regions according to the storage time by use of the modified thickness guage. The results were as follows. 1. Surface roughness (Rz) were $4.00{\pm}1.60{\mu}m$ in Mollosil, $4.47{\pm}2.21{\mu}m$ in Molloplast B, $7.46{\pm}1.70{\mu}m$ in Coe Super Soft, $12.70{\pm}2.39{\mu}m$ in Coe Soft and $13.03{\pm}2.74{\mu}m$ in K-33. 2. The generation of porosity was far more active in cold-cured resilient liners (Coe Soft and Mollosil) than in heat cured resilient liners (Molloplast B, and Coe Super Soft) and conventional heat cured resin (K-33). 3. Denture bases showed the greatest discrepancy at the central portion of the posterior palatal border and the intimate contact in the buccal flange regardless of denture base materials. 4. When the denture bases were stored in the water for 1 day and 6 weeks after processing, the sum of average discrepancies in the seven regions of the denture base was the greatest in K-33 followed by Molloplast B, Mollosil, Coe Soft and Coe Super Soft but followed by Coe Soft, Molloplast B, Mollosil, Coe Super Soft in that order respectively. 5. There was not a significant difference (p>0.05) in Coe Super Soft, K-33 but there was a significant difference (P<0.01) in Molloplast B, Mollosil, Coe Soft at the amount of dimensional changes according to the storage time.

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Treatment of Radioactive Liquid Waste Using Natural Evaporator and Resulted Exposure Dose Assessment (증발을 이용한 방사성 액체폐기물의 처리와 피폭선량평가)

  • Jeong, Gyeong-Hwan;Park, Seung-Kook;Kim, Eun-Han;Jung, Ki-Jung;Park, Hyun-Soo
    • Journal of Radiation Protection and Research
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    • v.24 no.2
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    • pp.101-108
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    • 1999
  • The influence of the relative humidity, the temperature and the velocity of supply air on evaporation rate has been studied with non-boiling forced evaporation system in order to treat very low level radioactive liquid wastes produced from the decontamination and decommissioning activities. Experimental data on the evaporation rate have been obtained with the divers variables and experimental equation of air velocity was also obtained by the correlation of those data. The decontamination factor of this system was also obtained by the experimental data from a simulated liquid waste containing Cs-137 radio isotope ; $DF=10^4$. Since the commercial system will be operated for the treatment of the very low level radioactive liquid waste produced from decontamination & decommissioning of TRIGA Mark-II&III research reactor, the environmental assessment has been conducted to improve the operational safety. Exposure dose rate for an individual member of general public was assessed, and it showed that it was very lower than individual dose limits. The release of radioactivity of radioisotope material (Cs-137) to the environment was assessed, and result showed that it was $4.637{\times}10^{-14}\;{\mu}Ci/cc$.

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High Energy Resolution Alpha Spectrometer Using a Cryogenic Detector (저온검출기를 이용한 에너지 고 분해능 알파분광 구현)

  • Kim, M.S.;Lee, S.H.;Yoon, W.S.;Jang, Y.S.;Lee, S.J.;Kim, Y.H.;Lee, M.K.
    • Journal of Radiation Protection and Research
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    • v.38 no.3
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    • pp.132-137
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    • 2013
  • Cryogenic particle detectors have recently been adopted in radiation detection and measurement because of their high energy resolution. Many of these detectors have demonstrated energy resolutions better than the theoretical limit of semiconductor detectors. We report the development of alpha spectrometer using a micro-fabricated magnetic calorimeter coupled to a large-area particle absorber. A piece of gold foil of $2{\times}2{\times}0.05mm^3$ was glued to the paramagnetic temperature sensor made of sputtered Au:Er film to serve as an absorber for incident alpha particles. We performed experiments with 241Am source at cryogen free adiabatic demagnetization refrigerator (CF-ADR). A high energy resolution of 6.8 keV in FWHM was obtained for 5.5 MeV alpha particles.

Ecological Studies on the Culture Bed and Production of Young Top Shell, Batillus cornutus in Cheju Island (제주도산 소라의 치패생산 및 서식생태에 관한 연구)

  • Pyen Choong Kyu;Youn Jeong Su
    • Journal of Aquaculture
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    • v.3 no.1
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    • pp.89-125
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    • 1990
  • In order to improve top shell seed production techniques spawning and larvae rearing were done in rearing tanks. Growth of young top shell in the nursing ground were also investigated. For induced spawning, top shells were maintained in still water during night time. Then they were treated with ultra violet iradiated sea water after dried up in air for 60 minutes. Spawning rate were 10 to $39.77\%$. It was found that young top shells moved in the growing grounds from nursing grounds when they reached approximately 30-40mm in shell heignt. Among main food algae for top shell in the natural growing grounds, sea mustard were melted away during June. Therefore, presence of another food algae such as Ecklonia cava or Sargassum spp. seems to be the main limiting factor for survival of top shell during summer. The tolerance of top shells ranging from 30mm to 60mm to low density of seawater for were tested at the temperature between 29.5 and $31.4^{\circ}C$. Hundred percent mortality occoured in 20, 55 and 90 hours after first stocking at the specific gravity of 1.010, 1.015, and 1.020, respectively.

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Energy Budget of the Mysid Shrimp, Neomysis intermedia Reared in the Laboratory (실내 사육한 Neomysis intermedia의 생활사에 따른 에너지 수지)

  • Choi, You-Gill;Rho, Sum;Chu. Soo-Dong;Park, Kie Young
    • Journal of Aquaculture
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    • v.10 no.3
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    • pp.289-300
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    • 1997
  • Energy budget of mysid shrimp, Neomysis intermedia in Lake Kyongpo was determined at constant temperature (2$0^{\circ}C$). Energy used by reared mysids were calculated from data on feeding, growth, molting, reproduction, and metabolism. The Energy used by growth of juvenile and adult were 6.87 cal in females of 8.55mm in length, and 5.67 cal in males of 7.53mm in length, respectively. Molting losses were estimated to be 0.46 cal in females and 0.38 cal in males from juvenile to adult. Energy used in respiration were estimated to be 48.48 cal in females and 36.45 cal in males from juvenile to adult. The energy intakes from feeding were 84.15 cal in females and 67.09 cal in males from juvenile to adult. Energy losses by excretion were 10.36 cal in females and 6.46 cal in males. Thus, females assimilated 86.65% and males 81.99% of assimilated energy in somatic growth. The gross growth efficiencies (k1) showed 8.71% for females and 9.02% for males and the net growth efficiencies (k2) showed 10.05% for females and 12.36% for males. Maintenance costs were estimated at 66.48% of assimilated energy in females and 66.26% in males. Molting losses among the energy assimilated from juvenile to adult were estimated to be 0.63% in males and 0.69% in females.

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Effect of Selected Spat on Growth of Bay Scallop (Argopecten irradians) During Aquaculture (해만가리비 Argopecten irradians 양식시 성장에 미치는 치패의 선발 효과)

  • 오봉세;양문호;정춘구;김주일;김영숙;김숙양
    • Journal of Aquaculture
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    • v.15 no.3
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    • pp.123-129
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    • 2002
  • In Nam-myeon coastal area of southern sea, Korea, the following hydrobiological conditions prevailed during 1997: water temperature: 12.6 ~24.5 $^{\circ}C$ ; Salinity: 27.32 ~33.$10 \textperthousand$, Dissolved oxygen: 7.05 $ml/L$ and Chlorophyll a: 1.69 ~ 7.40 $\mu $/L. Phytoplankton, dominated by Ceratium sp, peaked during June-July. Mean growth rates of the bay scallop of selected and non-selected groups cultured for 185 days in this area from July to December, 1997 were 0.17 and 0.19 mm/day for shell height, and 0.17 and 0.16 g/day for total weight, respectively. Maximum predicted values of shell height, calculated by von Bertalanffy growth model, were 54.98 mm for the selected and 52.62 mm for the non-selected groups. Survival of the selected and non-selected groups was 80.0 and 87.0%, respectively.

Developmental Changes in Digestive Enzymes Activity of Black Rockfish Sebastes inermis (볼락, Sebastes inermis 자.치어의 성장에 따른 소화효소 활성 변화)

  • Gwak Woo-Seok;Park Dae-Won
    • Journal of Aquaculture
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    • v.19 no.2
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    • pp.125-132
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    • 2006
  • Black rockfish larvae and juveniles were reared for 95 days after parturition (DAP) in order to determine four enzyme activities (trypsin, pepsine-like enzyme, lipase, amylase) during ontogeny. Larvae were fed rotifers Brachionus plicatilis from 1 to 25 DAP, Artemia nauplii from 10 to 78 DAP and then gradually changed to pelleted feed from 30 DAP. Temperature was kept between $13.5{\sim}14.9^{\circ}C$. Trypsin and lipase activities were found in 2 DAP larvae ($7.0{\pm}1.5$ unit and $4.5{\pm}1.4$ unit, $mean{\pm}SD$, respectively). The evolution of both enzymes activities showed a profile marked by drastic increases between postflexion and juvenile stage. There is an increment on specific trypsin activity at 10 DAP, corresponding with the beginning of Artemia feeding. Pepsin-like enzyme activity was found at 11 DAP and increased drastically from 56 DAP, cor-responding with the initiation of juvenile stage. Amylase activity was also found at 11 DAP and maintained at a low level up to 38 DAP followed by a drastic increase from 39 DAP to 50 DAP. Considering our results of both trypsin and pepsin-like enzyme activities, it might be concluded that higher somatic growth of Sebastes inermis could be possible with the initiation juvenile of stage and the early juvenile stage is a suit-able period for feeding an artificial diet for fish.

Improved Early Survival in Backcrosses of Male Mud Loach (Misgurnus mizolepis)$\times$Cyprinid Loach (M. anguillicaudatus) Hybrids to Femal Cyprinid Loach (미꾸리, Misgurnus anguillicaudatus의 생존율 향상을 위한 역교배체 생산)

  • 박인석;김봉석;임재현;박효민;남윤권;정창화;김동수
    • Journal of Aquaculture
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    • v.10 no.3
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    • pp.363-371
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    • 1997
  • Backcross hybridization between female cyprinid loach(Misgurnus anguillicaudatus) any male mud loach (M. mizolepis)$\times$cyjprinid loach hybrid were made, and its effect on early survival, cytogenetic traits, and gonad development were examined. Mean fertilization rate and hatching success of backcross hybrids were similar to those found in the maternal species, the cyprinid loach. However, the backcross hybrids revealed significantly improved early survival up to yolk sac absorption (86.0%) compared to cyprinid loach (0%) under low culture temperature ($15^{\circ}C$). the erythrocytic size and DNA content of backcross hybrids were nearly intermediate to those of the parents. Karyological analysis of backcross hybrids displayed two kinds of modal chromosome number of 2n=48 or 2n=49. Growth of backcross hybrids over 6 months after hatching was proven to be intermediate between their parental species. Although backcross hybrids had intermediate values between those of thier parents in most morphometric traits, overall external morphology of backcross hybrids was morer simlar to cyprinid loach than mud loach$\times$cyprinid loach hybrid. Histological examination of gonads at 2 and 4 months of age revealed that no female was obseved in backcross hybrid groups, suggesting the possibility of production of monosex male population.

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Spawning, Hatching and Larval Growth of Red and Black Clownfish Amphiprion melanopus (Red and Black Clownfish Amphiprion melanopus의 산란, 부화 및 자어성장)

  • Kim, Suk-Ree;Hur, Sung-Bum
    • Journal of Aquaculture
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    • v.20 no.4
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    • pp.239-247
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    • 2007
  • We studied spawning, hatching and larval growth of Amphiprion melanopus under laboratory conditions. Each time a fish spawned about 440 to 650 eggs. The eggs were hatched 9 days later. Nest colour of the eggs changed from clear yellow orange to greyish violet with processing of embryogenesis. With regard to spawning according to the substrates, the fish prefered red clay pot and ceramic pot to volcanic scoria and live rock. Hatching rate (%) of the eggs on the former substrates was significantly higher than that on the latter. The number of eggs varied with the food stuff supplied to the fish. The fish fed Tetra bits (commercial diet), meat of short necked clams and mussels, and astaxanthin showed significantly higher fecundity with 638 eggs than that fed only Tetra bits (477 eggs) or Tetra bits with meat of shellfish without astaxanthin ($549{\sim}553\;eggs$). Higher temperature ranging from 24 to $30^{\circ}C$ induced shorter incubation period and smaller total length, but higher hatching rate. The optimum salinity and L:D cycle with $60\;{\mu}mol$ photon $m^{-2}s^{-1}$ for hatching were 33 psu and 16:8, respectively. The newly hatched larvae about 4.6 mm in total length grew to 7.5 mm in one week, 18.8 mm in a month and 37.9 mm in 70 days after hatching.

Quality Characteristics of Dumpling Shell Added with White Lotus Leaf Powder (연잎가루를 첨가한 만두피의 품질 특성)

  • Park, Jin-Hee;Kim, Eun-Mi
    • Culinary science and hospitality research
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    • v.19 no.2
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    • pp.1-10
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    • 2013
  • This study was conducted to investigate the quality characteristics of dumpling shells with white lotus leaf powder added to them (WLL 0%, 1%, 2%, 3%, 4%). Water binding capacity and moisture content of dumpling shells were not significantly different. Solubility in $50^{\circ}C$, $60^{\circ}C$ and $70^{\circ}C$ of dumpling dough has decreased because of the addition of WLL. Swelling power of all groups has increased because of increased amount of WLL content and temperature. The mass, volume and water absorption rate of cooked dumpling shells decreased while the turbidity of cooked dumpling shells increased with the addition of WLL. L and b value of dumpling shells significantly decreased and a value of dumpling shells significantly increased because of increased amount of WLL contents. Hardness and adhesiveness of dumpling shells significantly increased in WLL2 and WLL3 groups. Cohesiveness, springiness, gumminess and chewiness of cooked dumpling shells were not significantly different according to the additions of WLL. In sensory evaluation, color, flavor, white lotus leaf flavor, taste and overall acceptability significantly increased in WLL3. Stickiness, softness, chewiness of cooked dumpling shells were not significantly different according to the additions of WLL. Overall, the result of this study indicates that the dumpling shell containing 3% WLL powder was most preferred among the groups.

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