• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.7 s.250
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• pp.692-699
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• 2006

In this work, $TiO_2$ nanoparticles were synthesized using $N_2-diluted$ and Oxygen-enriched co-flow hydrogen diffusion flames. The effect of flame temperature on the crystalline structure of the formed $TiO_2$ nanoparticles was investigated. The measured maximum centerline temperature of the flame ranged from 2,103k for oxygen-enriched flame to 1,339K for $N_2-diluted$ flame. The visible flame length and the height of the main reaction zone were characterized by direct photographs. The crystalline structures of $TiO_2$ nanoparticles were analyzed by XRD. From the XRD analysis, it was evident that the crystalline structures of the formed nanoparticles were divided into two sorts. In the higher temperature region, over the 1,700K, the fraction of formed $TiO_2$ nanoparticles having anatase-phase crystalline structure increased with increasing the flame temperature. On the contrary, in the lower temperature region, below the 1,600K, the fraction of anatase-phase nanoparticles increased with decreasing the flame temperature.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.70-70
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• 2003

조류의 배자는 포유류의 배자처럼 모체로부터 영양분을 공급받는 것이 아니라 알속에 저장되어 있는 영양물질로 발육한다. 배자의 발육은 대부분 체외에서 진행된다. 난자는 배란된 후 수정되어 난관팽대부에서 1세포기 수정란이 된다. 그 후 난관협부로 이동하여 최초로 분열이 일어나 배자의 발육이 진행되고, 산란시에는 세포수가 약6만여 개에 달한다. 따라서 수정란에 유전조작기법을 사용하기 위해서는 모체의 난관속에서 일어나는 배발생과 난각속에서 일어나는 개체발생을 위한 체외배양법과 대리난각 배양법이 확립되어 있어야 한다. 그와 같은 기술은 닭 수정란의 배 발생 관찰 및 분석과 유용한 물질을 생산하기 위한 형질전환 가금 연구에 중요한 기술로 사용되고 있다. 따라서 본 연구는 1세포기 닭 수정란의 체외배양과 대리난각 배양에 있어서 수정란의 조건과 대리난각의 조건이 배자의 생존율과 부화율에 미치는 영향을 조사하여 체외배양과 대리난각 배양에 의한 병아리 생산 효율을 제고하기 위한 기초자료를 얻고자 실시하였다. 주요 조사 항목은 수정란의 채란위치, 배자의 발생단계, 수정란의 무게, 대리난각용 계란의 보존 기간, 대리난각의 두께, 대리난각 두께의 감소율, 대리난각의 크기 등을 조사하여 배자의 생존율과 부화율에 미치는 영향에 대하여 조사하였다. 본 실험의 결과는 초기 발생이 빠른 배자가 생존율과 부화율이 높았으며, 본 실험에 사용한 대리난각용 계란의 보관기간이 짧을수록 배자의 생존율과 부화율이 높은 것으로 조사되었다(p<0.05). 그러나 대리난각용 계란의 크기와 대리난각의 두께 차이는 배자의 생존율과 부화율에 큰 영향이 없는 것으로 조사되었다.하였을 때 분할율은 68.0%였으며, 이중 12.0%가 상실배 또는 배반포로 발달하였다. 뿐만 아니라 10% FBS가 첨가된 TCM-199 배양액에 난관상피세포와 공배양을 실시하였을 경우는 72.0%가 분할하였으며, 이중 16.7%가 상실배 또는 배반포로 발달하였다. 이상의 결과로 볼 때 활성화 처리는 ionomycin과 6-DMAP 용액처리가 적합하며, 단위발생란의 체외배양은 보다 적합한 배양조건의 확립이 필요한 것으로 생각된다.icalcium lactate 공동배양은 체외배양에 별다른 영향을 미치지 못하는 것으로 나타났다.생산하는 것을 확인할 수 있었다.4시간에 등급별 회수율이 각각 GI(27.4%), GII(14.7%), GIII(43.2%), GIV(14.7%)로 나타났으며, 46~50시간에는 GI(12.0%), GII(12.0%), GIII(28.0%), GIV(48.0%)로 나타났다. 이상의 결과로 볼 때 미성숙 난자의 회수는 hCG 투여 후 29~34시간이 적합한 것으로 생각된다. 가금의 생산에 있어서 매우 효율적이고 주목할 만한 방법으로 사료된다. 것으로 나타났다.적외선.열풍 복합건조방법이 높게 나타나 이것은 곡물 표면에 원적외선 방사에의한 복사열이 전달되어 열장해를 받았기 때문으로 판단되며, 금후 더 연구하여 적정 열풍온도 및 방사체 크기를 구명해야 할 것이다.으로 보여진다 따라서 옻나무 유래 F는 포유동물의 생식기능에 중요하게 작용하는 것으로 사료된다.된다.정량 분석한 결과이다. 시편의 조성은 33.6 at% U, 66.4 at% O의 결과를 얻었다. 산화물 핵연료의 표면 관찰 및 정량 분석 시험시 시편 표면을 전도

• Journal of Sericultural and Entomological Science
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• v.6
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• pp.53-56
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• 1966

1. On the contrary to the general insect size, male is larger than female. 2. The possible number of eggs, the maximum number of eggs per a morh is average 225 eggs. 3. The periods of the eggs laid is around 3 days. 4. The growth period of larva is about 14 days. 5. The period from the unifection to death is an indirect proportion to number of the eggs. 6. The period from the pupation to flying is about 14 days, depending upon the temperature.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.262-270
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• 1983

The newly hatched nymphs of brown planthopper(BPH) were reared individually for two generations in test tubes, where young rice seedling was planted on agar solution, at $30^{\circ}C,\;25^{\circ}C\;and\;20^{\circ}C\;with\;95\%,\;75\%,\;65\%\;and\;35\%$ R.H. Effects of $30^{\circ}C$ on the development of BPH when compared with those of $25^{\circ}C$ are followings. Egg period, nymphal period, and adult longevity were shortened. Nymphal mortality was increased and the number of oviposited eggs was decreased. Hatchability was zero per cent because the eggs were either unfertilized or died before finishing the development. At the low temperature of $20^{\circ}C$, in comparision with $25^{\circ}C$, the developmental period of nymphs and eggs was considerably lengthened, and adult longevity was shortened, the number of oviposited eggs was decreased. The nymphal mortality was higher at high relative humidity $(above\;75\%\;RH)$ than that at low relative humidity $(under\;65\%\;RH)$. Under the condition of high relative humidities, the adult longevity was shortened, and the number of oviposited eggs was decreased.

• Journal of Sericultural and Entomological Science
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• v.51 no.1
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• pp.73-77
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• 2013

Silkworm transgenesis scientists have done some genetic modification work on multivoltine silkworms, but that type of silkworms is less commercial feasible. They are easy to manipulate, because they breed all year round. But the commercial silkworm variety must undergo hydrochloric acid treatment at a high temperature to be artificially hatched. Hydrochloric acid penetrates through the holes in the silkworm eggs, fatally damaging their reproduction. So it had been thought that altering the properties of the commercial silkworm variety would be very difficult. So we have tried to make from diapause to non-diapause eggs using diapauses varieties, 'Backokjam' and 'Jam 124'. At present, our group has establishing the conditions for non-diapause eggs. Oviposited eggs after 40 ~ 60 hours were incubated for 24 hours at $15{\sim}20^{\circ}C$ with dark condition. Non-diapause eggs were completely induced. The hatching rate, molting rate and pupation rate of non-diapause 'Jam 124' and 'Backokjam' eggs showed no differences compared to diapause eggs. When transgenic silkworm using the non-diapause eggs, the hatching rate showed that non-diapause eggs induced from diapause were 40 ~ 70%, diapause eggs treated with artificial incubation were 10 ~ 30%, and polyvoltine strains, HM eggs were 30 ~ 50%. Therefore, we suggest that modification techniques of the commercial silkworm eggs adequate for silkworm transgenesis can be used to develop transgenic silkworms more easily.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.203-209
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• 2001

Development and reproduction of the sweetpotato whitefly, Bemisia tabaci(B biotype) were investigated under different temperatures and host plants. Developmental periods from egg to pre-adult of whiteflies measured under four constant temperatures: they were 86.2 days at $15^{\circ}C$ and 17.0 days at $30^{\circ}C$. Lower threshold temperature and total effective temperature for the development of egg and nymph, and for the complete development (egg to emergence) were $10.1,\;11.6,\;11.1^{\circ}C$ and 110.3, 204.7, 317.3 degree days, respectively. The hatching and emergence rates were 87.0% at $25^{\circ}C$ and 76.7% at $20^{\circ}C$, which were higher than the results of other temperatures. The adult longevity was 23.6 and 14.0 days at $20^{\circ}C$ and $30^{\circ}C$, respectively. The highest average fecundity per female was 103.3 at $25^{\circ}C$. But there were no significant differences among the temperatures. The highest intrinsic rate of natural increase($r_{m}$) was 0.196 at $30^{\circ}C$ and the highest net reproduction rate ($R_{o}$) was 97.33 at $25^{\circ}C$. Developmental periods from egg to pre-adult of whiteflies were 21.2 on the tomato, 28.1 on red pepper, 22.2 on eggplant and 25.5 days on poinsetia. The hatching was highest (90.3%) on red paper and emergence rate was highest (89.6%) on eggplant. The longest longevity of adult female was 26.5 days on eggplant, and the average fecundity per female was greater on tomato and eggplant than on other host plants. The intrinsic rate of natural increase($r_{m}$) was the highest on tomato as 0.165 and the net reproduction rate ($R_{o}$) was the highest on eggplant as 106.1. As a result, the optimum range of temperature for the growth of B. tabaci was between $25^{\circ}C$ and $30^{\circ}C$, and the optimum host plant were tomato and eggplant among the plants tested.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.143-149
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• 1998

Development and life table statistics of indian meal moth (Plodia interpunctella, Hiibner)on brown rice (Sativa oryzae L., var 'Ilpum' ) were tested under five different temperatures (17, 20, 25,28 and 3 2 f 0.5"C). The developmental response of females to the temperature was not significantlydifferent from that of males. In the tested temperature range, developmental period and life span of adultmoth decreased as the temperature increased and ranged from 149.9f30.4 to 38.1 k5.6 days and from19.4f 5.1 to 6.9k2.0 days at 17$^{\circ}$C and 32"C, respectively. Emergence rate increased with the increaseof temperature and ranged from 13.0f 6.2% at 17$^{\circ}$C to 49.2f 25.9% at 32$^{\circ}$C. However, hatching ratecurve in relation to the temperature was dome shape with the peak of 73.8 k5.37~a t 25"C, suggesting thathatching is inhibited by high temperature above that temperature. As the temperature increased, femalesconcentrated their oviposition on the second day after emergence. In the temperature range of 17 SIM 25"C, the number of eggs laid per female were not related to the temperature and ranged from 133.4f 37.6to 154.3k57.4. But the number of eggs laid per female decreased at 32$^{\circ}$C which suggests closerelationship with hatching ability. The net reproduction rate was highest at 28$^{\circ}$C and followed by those at25$^{\circ}$C and 20$^{\circ}$C. However intrinsic rate of natural increase of the moth population on brown rice wasestimated to be highest at 32$^{\circ}$C (0.065 per day), probably due to the short developmental period, highemergence rate and the concentrated oviposition of females on earlier days of the emergence.ition of females on earlier days of the emergence.

• Journal of fish pathology
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• v.11 no.2
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• pp.113-117
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• 1998

The influence of temperature on the rate of egg production and embryonic development of Microcotyle sebastis was investigated to determine the precise time of a second treatment. The survival time of the adults of M. sebastis was inversely proportional to temperature. The number of laid eggs per each replicate during the first 24 h was $39.3{\pm}4.0$ at $10^{\circ}C$, $62.7{\pm}14.2$ at $15^{\circ}C$, $101.0{\pm}5.6$ at $20^{\circ}C$ and $89.0{\pm}11.0$ at $25^{\circ}C$. The time required for egg hatching of M. sebastis was $31.30{\pm}4.88$, $17.52{\pm}3.24$, $11.59{\pm}3.02$ and $10.76{\pm}3.10$ days at 10, 15, 20 and $25^{\circ}C$, respectively. The regression models of the time required for the beginning and 50% point of hatching according to the different temperatures were as follows; Beginning of hatch: D=58.2000-$4.2067{\times}Temp+0.0867{\times}(Temp)^2$ ($P\leq0.01$), 50% of hatch: D=91.3833-$7.5767{\times}Temp+0.1767{\times}(Temp)^2$ ($P\leq0.01$).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.842-851
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• 1998

Development and growth of Acartia steueri from Ilkwang Bay, southeastern coast of Korea, were determined under various temperatures and food condition (Isochrysis galbana and Dunaliella salina) in the laboratory. Relationship between egg hatching time ($D_E$, day) and temperature (T, $^{\circ}C$) was $D_E=744(T+3.5)^{-1.97}$. Mean hatching success was $88.4\%$ in temperature range of $8.4\~26.2^{\circ}C$. This suggests that A. steueri may be adapted to the temperature ranges in temperate regions. Post-embryonic development pattern was equiproportional rather than isochronal, with longer stage duration of copepodites than that of the nauplii. Stage duration of NI was the shortest of all developmental stages, while the duration of NII was the longest in duration of the other nauplii. Male was morphologically distinguished from female in CIV stage, and male was developed faster than female. Median development time at a given temperature was calculated from the Belehradek equation by proper multiplication of proportional constant for embryonic development. Body carbon weight at $19.1^{\circ}C$ was increased exponentially with time. Mean specific growth rate of nauplii (0.200 $d^{-1}$), except for NI stage, was not significantly different from that of copepodites (0.190 $d^{-1}$), with the lowest rate in NVI stage (0.107 $d^{-1}$), probably due to energy consumption for metamorphosis rather than somatic growth. The results suggest that although the development pattern determined in this study was not identical with Uye's result for A. steueri (e.g. Uye, 1980b), median development time may be applicable to calculate the stage duration of A. steueri in this study area.

• Korean journal of applied entomology
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• v.36 no.1
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• pp.48-54
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• 1997

This study was conducted to determine the effect of temperatures and food sources on the egg and larval developmentof the tobacco cutworm, Spodoptera litura Fabricius. The hatchability of egg masses of S. liturawas 100% on the leaf of soybean, perilla and sweet potato in any given temperature regimes, while the hatchabilitywas only 65-8796 when reared on the pulp paper and decreased as temperature increased. Egg durationwas not significantly different among different food sources within each temperature. However, egg duration at32$^{\circ}$C was shorter than that at 24$^{\circ}$C and 28$^{\circ}$C. During the early larval development, at 28$^{\circ}$C and 32$^{\circ}$C the larvafed on sweet potato leaf was heavier than those fed on soybean and perilla leaves and the opposite case wastrue during mid-larval development stage. However, larval weight at 24$^{\circ}$C was heavier on sweet potato leafthan that on soybean and perilla leaves until 12 days after hatching. This result was probably due to relativelyslower developmental rate at 24$^{\circ}$C compared to 28$^{\circ}$C and 32$^{\circ}$C. The mean larval mortality was 68.896, 44.5%and 33.8% at 24$^{\circ}$C. 28$^{\circ}$C and 32"C, respectively. The lowest mortality was observed on soybena leaf and followedby perilla and sweet potato leaves, and artificial diet regardless of temperature conditions. The durationwas the shortest when they fed on soybean leaf, and followed by perilla and sweet potato leaves and artificialdiet. Larval durations were 23.6-30.4 days at 24$^{\circ}$C. 18.6-22.3 days at 28$^{\circ}$C and 14.5-18.0 days at 32$^{\circ}$C. Thethreshold temperatures of egg and larva of S. litura were about 6.l"C and 10.9"C, respectively.t 6.l"C and 10.9"C, respectively.pectively.