• Korean Journal of Environmental Agriculture
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• v.4 no.2
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• pp.118-125
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• 1985

To establish an evaluation system of aquatic toxicity of chemicals at no-effect level, flow through and early life stage toxicity test were performed on a freshwater fish, the medaka (Oryzias latipes). The characteristics of medaka as a bioassay organism for the chronic toxicity test were discussed. Maximum acceptable toxicant concentration(MATC) of butachlor for the madaka in soft water was estimated using survival, growth, and reproduction as indicators of toxic effects. During a 3-month period, the fry of medaka were exposed to butachor concentrations ranging from 0.16 to 0.0l mg/liter and the DO concentration, temperature, and pH in the exposure chamber were measured to check the test condition. The highest concentration showed slight decrease of growth rate in medaka and reduced hatchability of spawning egg. Survival, growth, and reproductive success of adults in butachlor concentration of 0.04 and 0.01 mg/liter were not different from those of the control. The MATC was estimated to be between 0.04 and 0.16 mg/liter for medaka.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.111-115
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• 2001

Orius strigicollis Poppies is an indigenous natural enemy of thrips pests in Korea To develop an efficient mass rearing system for Ο. strigicollis, effects of hatchability, egg numbers and egg harvesting time of Ο. strigicollis were measured in cylindrical cage (251 ㎤) under the conditions of photoperiod 16L : 8D, $55\pm$10% RH and $25\pm$$2^{\circ}C$. The hatchability and developmental period of eggs were 88.5% and 5.7 days, respectively. The highest emergence rate (50.8%) was achieved when the number of eggs laid was ranged from 50 to 100 per arena. The proper harvesting time of newly produced adults was 17 days postoviposition. Relationship between the number of resulting adults per female and the number of female adults per arena was Y : -10.7971n (X) +44.659 ($R^2$=0.7619). The generation time (T), the net reproductive rate ($R_{0}$ ) and the intrinsic rate of natural increase ($r_{m}$ ) were 26.5 days, 6.18 and 0.0687, respectively.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.269-274
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• 2009

Rearing media were selected for the production of sterile larvae of greenbottle blowfly, Phaenicia (=Lucilia) sericata (Meigen) which is widely used in maggot therapy. Eight media available in the market were used in this study. Egg hatchability was not different among the media. Survivorship of the larvae was higher in blood agar (BA), sabouraud dextrose agar, and brucella blood agar than the others. A higher content (20${\sim}$40%) of sheep blood in BA and chocolate agar increased the survivorship of larvae. The eggs and the early 3rd larvae could be stored for 12 days at $8^{\circ}C$ and for 15 days at $6^{\circ}C$ without decrease in hatchability and larval survivorship, respectively.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.3
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• pp.173-182
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• 2022

Dongsuak crater, located in the mid-mountainous region of Jeju Island, is located at an altitude of about 700 m, and the newly discovered Dongsuak spinel peridotites was enclosed in Dongsuak alkaline basalt. The Dongsuak spinel peridotites are composed of olivine, orthopyroxene, clinopyroxene, and spinel with porphyroclastic texture under the an equilibrium state. The variations of mineral major and trace compositions indicates that the Dongsuak spinel peridotites originate at depth from 66 to 88 km under an equilibrium temperature of about 960℃~1068℃. The Dongsuak spinel peridotites have been undergone about 1~3% fractional melting. The LREE-enriched characteristics indicate that the Dongsuak spinel peridotites have been undergone cryptic metasomatism by silicate melt without new minerals.

• Journal of Sericultural and Entomological Science
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• no.11
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• pp.55-57
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• 1970

There are many reports concerning to the restoring times, and the range of times are very wide. Author restored the artificial hatching silkworm eggs 1 ice pit (5$^{\circ}C$) two different method; one restored in directly after protected following different times 24 hours, 48 hours and 72 hours of room temperature (24$^{\circ}C$), another protected above suggested times and room temperature then indirectly keeping medium temperature (1$0^{\circ}C$)6 hours. It was incubated in $25^{\circ}C$ temperature after about 20 days of restoring. Pure line and hybrid silk warm eggs are no difference hatching ratio in 72 hours blocks by restoring. Especially good hatching ratio obtained by the medium temperature treatment rather than directly restoring.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.10a
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• pp.34-35
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• 1994

기체혼합물의 분리및 정제기술은 에너지 절약의 관점과 새로운 기능성 고분자의 개발로 고분자막에 의한 분리법이 관심을 끌게되었다. 공기로부터 산소부화, 방사성 크세논 및 크립론의 제거, 제련소 폐가스증의 수소분리, 천연가스로부터 헬륨의 회수분야등은 실제로 산업적으로 실용화되고 있다. 그러나 고분자막은 일반적으로 투과성과 선택성이 서로 상반되는 경향을 나타내므로, 투과성과 분리성이 좋은 기능성 고분자막의 개발에 다양한 연구가 필요로 하고있다. 본 연구에서 사용한 PTFE(polytetrafluoroethylene)는 결정성 고분자로서 넓은 온도범위에서 낮은 마찰계수, 우수한 전기적 절연특성, 강한 Carbon-fluorine 겹합에 기인한 높은 열적 안정성, 화확적 불활성때문에 공업용 고분자 재료로서 독특한 위치를 차지하고 있다. 최근에 미국과 일본을 주축으로 상용화딘 공기전지(Zinc-air battery)는 PTFE막의 뛰어난 소수성과 화학적 저항성으로 수은 전지의 대체품으로 주목받고 있는데, 장기 방전시 성능 저하가 따르므로 막을 통한 산소투과성을 방전에 필요한 최소값으로 감소시키는 것이 중요한 과제가 되고있다.

• KOREAN POULTRY JOURNAL
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• v.40 no.7
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• pp.129-131
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• 2008

국내에서 발생하고 있는 닭 질병 중에서 심각하게 경제적인 피해를 일으키는 질병들은 주로 온도가 낮은 시기에 집중되어 있다. 하절기에는 몇몇 세균성 질병을 포함하여 고온다습한 환경 조건에 닭이 노출됨으로써 오는 일사와 열사병, 곰팡이 독소 중독증 그리고 가금티푸스를 포함한 몇몇 세균성 질병 등이 주를 이룬다. 그러나 간과해서는 안 될 것은 여름철이라고 해서 환절기와 동절기에 바이러스성 질병의 발생이 없는 것이 아니라 사육환경이 좋아짐으로써 질병의 증상이 잘 드러나지 않고 피해가 나타나지 않을 뿐 각종 질병의 발생이 계속되고 있다는 사실이다. 더위는 털이 많은 닭에게 있어서 분명 견디기 힘든 환경일 것이다. 더위로 인해 겪는 계군의 피해는 사료섭취 감소, 산란저하, 난중감소, 난각질 저하, 부화율 저하, 사료효율의 저하와 스트레스 호르몬의 분비에 의해 성장저하 및 면역시스템에 좋지 않은 영향을 주어서 질병에 대한 감수성이 높아지게 만든다. 계군이 더위를 잘 이기게 해주는 일련의 관리방법들은 계군에 대한 스트레스를 감소 시켜주어 결국은 닭의 면역시스템을 보호해 주는 넓은 의미의 질병 예방 관리라 할 수 있을 것이다. 7월의 폭염을 계군이 효과적으로 이길 수 있게 해 주는 일반적인 관리방법들을 나열해 본다.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.325-330
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• 2005

This study was conducted to determine the effect of temperatures on the egg and nymphal development, adult longevity and oviposition of bean bug, Riptortus clavatus Thunberg, using Saealkong seed as food sources in fibrous nylon-tube at four different temperatures (20, 24, 28 and $32^{\circ}C$). Hatchability showed the highest value of 100% at $28^{\circ}C$ and decreased with increasing temperature. Egg duration ranged from 7 days at $32^{\circ}$ to 16.7 days at $20^{\circ}C$. Instar duration was longer with increasing instar stage. Nymphal duration was 38 days at $20^{\circ}C$, 30 days at $24^{\circ}C$, 23 days at $28^{\circ}C$, and 18 days at $32^{\circ}C$ Emergence rates to adult were 16, 41, 72 and 68% at 20, 24, 28 and $32^{\circ}C$, respectively. Female adult longelity ranged from a minimum 20 days at $20^{\circ}C$ to a maximum 63 days at $28^{\circ}C$, while the longevity of male ranged from 19 days at $20^{\circ}C$ to 60 days at $28^{\circ}C$. Preoviposition duration was shorter with increasing temperature and ranged from 11 days at $20^{\circ}C$ to 5 days at $32^{\circ}C$. Total number of eggs laid per female ranged from a minimum 21 eggs at $20^{\circ}C$ to a maximum 67 eggs at $28^{\circ}C$. Consequently, the estimated lower threshold tempeatures of each developmental stage were $10.3^{\circ}C$ for egg, and 9.3, 12.7, 10.0, 11.0 and 8.7 for the 1st, 2nd, 3rd, 4th and 5th instar, respectively.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.387-394
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• 2013

The developmental times of mealworm beetle larvae, Tenebrio molitor were studied at six temperatures ranging from 15 to $30^{\circ}C$ with 60~70% RH, and a photoperiod of 14L:10D. Mortality of larval period was very low at 17 and $20^{\circ}C$ but did not die over $22^{\circ}C$. Developmental time of larva was decreased with increasing temperature. The total developmental time of T. molitor larvae was longest at $17^{\circ}C$ (244.3 days) and shortest at $30^{\circ}C$ (110.8 days). Egg and larvae were not developed at $15^{\circ}C$. The lower developmental threshold and effective accumulative temperatures for the total larval stages were $6.0^{\circ}C$ and 2564.1 degree-days, respectively. The relationship between developmental rate and temperature was fitted by a linear model and nonlinear model of Logan-6($r^2$=0.95). The distribution of completion of each development stage was well described by the 2-parameter Weibull function ($r^2$=0.8502~0.9390).

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.77-85
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• 1996

The study on the ripening of leather waste sludge was performed to vemistabilize the sludge effectively using a laboratory scale darkened wood box reactor ($10{\times}10{\times}20cm$). The acceptable feed conditions for earthworm of Eh, alkalinity were obtained in the 30th and 35th days, respectively. The value of pH was gradually decreased from 7.8 to 7.1 through the ripening time. The contents of heavy metals of the ripened sludge were estimated as lower levels compared to the other regulatory standards for compost. After the ripening time for 50days, the physico-chemical properties of the sludge were estimated as pH 7.1, water content 72%, redox potential 85mV, electrolytic conductivity $2,620{\mu}mhos/cm$ and alkalinity 450 ppm as $CaCO_3$, respectively. In the ripened sludge, survival rate of the earthworms for 50 days was about 75%, and the live weight increase rate was about 230% at the temperature range of $20{\sim}25^{\circ}C$. Moreover, hatching rate of the earthworm cocoons was about 87% and the highest value was obtained in the 20~30th days. From the above results, it was evaluated that leather waste sludge could be vermistabilized effectively by earthworms, when the sludge was ripened during 50 days.