• Title/Summary/Keyword: Dead water

Search Result 353, Processing Time 0.024 seconds

The Ignition Characteristics of Dead Leaves and Living Leaves of Various Trees in Young Dong Forest Areas (영동지역 주요 수종별 낙엽과 생엽의 착화특성에 관한 연구)

  • Park, Young-Ju;Lee, Si-Young;Sin, Young-Ju;Kim, Su-Young;Kim, Young-Tak;Lee, Hae-Pyeong
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
    • /
    • 2008.04a
    • /
    • pp.298-302
    • /
    • 2008
  • In this study, we have carried out the test to examine the ignition characteristics, such as a relation of moisture content and combustibility, and ignition temperature using KRS-RG-9000 tester, living leaves and dead leaves of significant 7 species of Young Dong Provinces of Korea after and before the rainfall. After 144 hours at normal temperature, the percentage of water content of the needle-shaped leaves was less than 10%. So it is suppose to be ignite easily. On the other hand, the self-temperature to ignite of broadleaf is higher. So the retard time at lower temperature is more long than needle-shaped leaf. Consequently, the fire-resistant qualities of broadleaf is higher than needle-shaped leaf.

  • PDF

Treatment of Dactylogyrosis in Oscar (Astronotus ocellatus) (오스카(Astronotus ocellatus)에서의 아가미흡충증 치료)

  • Lim Kyung-taek;Kim JI-hyung;Park Jae-hak;Shin Nam-shik;Heo Gang-joon;park Se-chang
    • Journal of Veterinary Clinics
    • /
    • v.22 no.2
    • /
    • pp.160-162
    • /
    • 2005
  • Dead oscars (Astronotus ocellatus) were presented for necropsy in January, 2005. Oscars, which had been reared densely, were dead in large quantities. At necropsy, they were severely infected by Dactylogyrus spp. We requested for the oscar samples which had been raised in the same water tank. Two of them were sacrificed and necropsied. At the microscopic examination, we verified dactylogyrosis of oscars. The other oscars were treated by praziquantel. Treatment was started with a dosage of 2.5 mg/L. From a second day, we treated 5.0 mg/L every two days during 4 days. At sixth day, No Dactylogyrus flukes were found but only larvae were existed. After 2 weeks without additional medication, both Dactylogyrus flukes and larvae were eliminated.

Reform of sacrificial ritual model through the empirical tests of reformative model far Korean sacrificial rite (제례 재구성 모델의 실증적 검증을 통한 제례 모델 재구성)

  • 두경자
    • Journal of Families and Better Life
    • /
    • v.19 no.6
    • /
    • pp.241-263
    • /
    • 2001
  • The objectives of this study were empirically to test the reformative model for Korean sacrificial rite and to investigate the effects of demographic variables. the survey was conducted by means of questionnaire with 600 persons located in Seoul. Major findings were as follows ; 1, Sacrificial day ; was displayed (1) dead day (2) holiday in back and forth of dead day 2. Sacrificial time ; was showed (1) 8-9 h. p.m (2) 6-7 h. p.m 3. Sacrificial extent ; was displayed (1) grandparents and parents (2) only parents 4. Participative extent ; was showed (1) Cousin (2) only sons and daughters 5. Sacrificial procedure ; was displayed twice deep bow and 1 minute\`s silent prayer. 6. New year's and Chusok's rite ; was showed (1) simple foods (2) joint leisure time 7. Sacrificial table ; was displayed (1) boiled rice . water . gustoish articles. (2) omission of food table 8. rite\`s socialization ; was showed (1) delivery and marketing sale\`s food (2) special sacrificial restaurant. 9. Womens'and mens'difference ; women were active 7ut men were passive 10. Age's difference ; excepting 30-40, the all generations were more reformative. 11. Number of brothers ; small number of brothers were more reformative than a many number. 12. Sacrificial manager or not , managers were conservative than persons were not managers.

  • PDF

The Effect of $ZrO_2-Y_2O_3\;(YSZ)$ Buffer Layer on Layer on Low-Field Magnetoresistance of LSMO Thin Films ($ZrO_2-Y_2O_3\;(YSZ)$ 중간층이 저 자장영역에서의 LSMO 박막의 자기저항 특성에 미치는 영향)

  • 심인보;오영제;최세영
    • Journal of the Korean Magnetics Society
    • /
    • v.9 no.6
    • /
    • pp.306-311
    • /
    • 1999
  • $La_{2/3}Sr_{1/3}MnO_3(LSMO)/YSZ/SiO_2/Si(100)$ polycrystalline thin films were fabricated be chelated sol-gel method The effect of YSZ buffer layer at low field (120 Oe) spin-polarized tunneling magnetotransport (TMR) properties of LSMO thin film was studied at room temperature. Single perovskite LSMO thin films was obtained. The maximum TMR ratio was increased from 0.2 to 0.42 % by the insertion of YSZ buffer. YSZ as diffusion barrier was attributed to the fine microstructure of LSMO thin films and the reduction of dead layer between LSMO and $SiO_2/Si(100)$ interfaces.

  • PDF

Permeation Behavior of Semiconductor Rinsing Wastewater Containing Si Particles in Ultrafiltration System -I. Permeation Characteristics of Polysulfone Flat Plate Membrane- (Si 입자를 함유한 반도체 세정폐수의 한외여과 특성[I] -Polysulfone 평판막에 의한 투과분리-)

  • 곽순철;이석기;전재홍;남석태;최호상
    • Membrane Journal
    • /
    • v.8 no.2
    • /
    • pp.102-108
    • /
    • 1998
  • Permeation behavior of the semiconductor rinsing wastewater containing Si particles was examined by ultrafiltration using the polysulfone plate membrane. The permeation flux was gradually decreased with time. It was due to the growth of cake deposited on the membrane surface and the pore plugging by Si particles. Permeation flux of cross flow type was 1.4 times higher than that of the dead end flow type. Nitrogen back flushing which is the removing method of membrane fouling was superior to the water sweeping. With nitrogen back flushing, the decrease of permeation flux due to the fouling was recovered about 85 % to the initial flux in the flat plate membrane system. The rejection rate of Si particles was about 90 % and the size of Si particle in the permeate was about 70 nm.

  • PDF

The Effect of Yellow Soil on Mortality of Korean Scallops, Patinopecten yessoensis at Indoor Tank

  • Oh, Bong-Se;Jung, Choon-Koo;Kwon, Mun-Gyeong;Lee, Jung-Sick
    • The Korean Journal of Malacology
    • /
    • v.26 no.3
    • /
    • pp.179-183
    • /
    • 2010
  • In other to understand the effect of yellow soil to mortality of Korean scallops, P. yessoensis, We investigated its mortality at indoor tanks. The environmental conditions such as water temperature, Salinity, Do and pH were continued constantly during the experimental periods. The 100% of survival rate showed in two experiments groups such as 0.1% and 0.4% of concentration of yellow soil and the other groups as 0.05% and 0.2% of concentration of yellow soil was appeared one dead scallop at each group for 8 days of the experiment periods. the gills of scallop in high concentration of yellow soil (0.2% and 0.4% groups) were covered by yellow soil particles so that this group's scallop should be got a high stress from yellow soil. I think this situation will be more continued for long time the scallop will become to dead. The results of bacteriological analysis did not isolated from haemolymph of scallops and no Perkinsus infectious disease in scallops and the scallops showed necrosis and degeneration on digestive grand and gills of scallop.

Biological Treatment of Nutrients and Heavy Metals in Synthetic Wastewater Using a Carrier Attached to Rhodobacter blasticus

  • Kim, Deok-Won;Park, Ji-Su;Oh, Eun-Ji;Yoo, Jin;Kim, Deok-Hyeon;Chung, Keun-Yook
    • Applied Chemistry for Engineering
    • /
    • v.33 no.6
    • /
    • pp.666-674
    • /
    • 2022
  • The removal efficiencies of nutrients (N and P) and heavy metals (Cu and Ni) by Rhodobacter blasticus and R. blasticus attached to polysulfone carriers, alginate carriers, PVA carriers, and PVA + zeolite carriers in synthetic wastewater were compared. In the comparison of the nutrient removal efficiency based on varying concentrations (100, 200, 500, and 1000 mg/L), R. blasticus + polysulfone carrier treatment showed removal efficiencies of 98.9~99.84% for N and 96.92~99.21% for P. The R. blasticus + alginate carrier treatment showed removal efficiencies of 88.04~97.1% for N and 90.33~97.13% for P. The R. blasticus + PVA carrier treatment showed removal efficiencies of 18.53~44.25% for N and 14.93~43.63% for P. The R. blasticus + PVA + zeolite carrier treatment showed removal efficiencies of 26.65~64.33% for N and 23.44~64.05% for P. In addition, at the minimum inhibitory concentration of heavy metals, R. blasticus (dead cells) + polysulfone carrier treatment showed removal efficiencies of 7.77% for Cu and 12.19% for Ni. Rhodobacter blasticus (dead cells) + alginate carrier treatment showed removal efficiencies of 25.83% for Cu and 31.12% for Ni.

Experimental Studies on the Second Intermediate Hosts of Clonorchis sinensis II. Observations on the fate of encysted cercariae of Clonorchis sinensis in the fish hosts, Pseudorasbora parva, Acheilognathus signifer and Acanthorhodeus asmussi (간흡충(肝吸蟲)의 제이중간숙주(第二中間宿主)에 관한 실험적(實驗的) 연구(硏究) Ⅱ. 참붕어, 묵납자루 및 큰납지리 체내(體內)에 있어서 간흡충(肝吸蟲) 피낭유충(被囊幼蟲)의 운명(運命)에 관하여)

  • Rhee, Jae Ku
    • Korean Journal of Veterinary Research
    • /
    • v.13 no.2
    • /
    • pp.147-160
    • /
    • 1973
  • The present experiments proposed to pass judgement upon the suitability as the second intermediate host of Clonorchis sinensis, of three kinds of fresh-water fish by having them infected with the cercaria of Clonorchis sinensis and then observing the penetrating ability of the cercaria, and maturity, the process of degeneration and extinction, and infectivity of the metacercaria of Clonorchis sinensis. The following is a brief summary of the leading facts gained through the experiments; 1. P. parva was easily subject to invasion of the cercaria, A. signifer was much less subject to the invasion, and finally A. asmussi was hard to invade. And the infectivity of the cercariae was in proportion to their penetrating ability mentioned in the above. 2. The examination of the cercariae after having three kinds of fresh-water fish infected with them disclosed that 24 hours after the infection, all of the cercariae formed their cysts in muscle and the metacercariae kept growing, and that 7 days later the metacercariae were found folding their bodies twice, and that in 15 days the characteristic structure of the metacercariae was complete and they made a vigorous rotary movement intermittently. 3. Then the metacercariae came to a state of maturity and beyond this stage some metacercariae in P. parva started the process of degeneration and extinction in 133 days; some in A. asmussi, in 140 days; and A. signifer, in 70 days. As more days elapsed, their degeneration and extinction increased in number, and in 269 days all of them in A. signifer became dead while those in A. asmussi were all dead in 460 days. However almost all of them in P. parva survived even after 770 days. The results shown above revealed that P. parva was the most suitable as the second intermediate host among three kinds of fresh-water fish and that A. signifer and A. asmussi were not quite recommendable as the second intermediate host. The ability of the cercaria to invade fresh-water fish, and life span of the metacercaria within fresh-water fish vary outstandingly according to species of fresh-water fish. An explanation as to the mechanism must wait as the subject to be further pursued.

  • PDF

The Effect of Water Temperature on Egg Developmental Stages of Largescale Blackfish Girella punctata and Smallscale Blackfish Girella melanichthys (벵에돔 Girella punctata와 긴꼬리 벵에돔 Girella melanichthys의 난 발생에 미치는 수온의 영향)

  • Oh, Bong-Se;Choi, Young-Ung;Ku, Hag-Dong;Kim, Sung-Chul;Jung, Min-Min;Park, Heung-Sik
    • Development and Reproduction
    • /
    • v.14 no.2
    • /
    • pp.51-58
    • /
    • 2010
  • This research investigated that the effect of water temperature on egg developmental stages of largescale blackfish Girella punctata and smallscale blackfish Girella melanichthys. The required times from fertilized embryos to hatching for the G. punctata were 67.8~37.5 hrs from 15 to $21^{\circ}C$, shorter as the water temperature increased. But fertilized embryos were dead after Kuffer's vesicle appearance stage at $24^{\circ}C$ and morula stage at $27^{\circ}C$. Biological minimum temperature (starting point for embryonic development) of the egg development was estimated to be $7.6^{\circ}C$ in average. In G. melanichthys, fertilized embryos were hatched within 61.2~38.3 hr from 15 to $21^{\circ}C$, the times were shorter as the water temperature increased to hatching, but its were dead on above $24^{\circ}C$. Biological minimum temperature of the egg development was estimated to be $6.5^{\circ}C$ in average. Based upon these results, it is recommended that the range of optimum water temperature for embryonic development of G. punctata and G. melanichthys is $15{\sim}21^{\circ}C$.

Hydraulic Residence Time in a Prototype Free Water Surface Constructed Wetland

  • Lee, Kyung-Do;Kwun, Soon-Kuk;Kim, Seong-Bae;Cho, Young-Hyun;Kim, Jin-Ho
    • Korean Journal of Environmental Agriculture
    • /
    • v.24 no.1
    • /
    • pp.6-11
    • /
    • 2005
  • A prototype surface flow constructed wetland was built in the upstream area of reclaimed tidal lands to improve the water quality of Lake Sihwa by treating severely polluted stream water. In this study, a tracer test using rhodamine-WT was performed to investigate the flow characteristics and to quantify the observed hydraulic residence time (HRT) for a high-lying cell in the Banwol wetland of the Sihwa constructed wetland. The tracer test indicated that even if flow was mainly observed in the open water area of the Banwol wetland, water flowed continuously in the vegetative area and there was no dead zone. The calculated HRT (51.3 hrs), calculated by dividing the wetland volume by the wetland inflow, exceeded the observed HRT (38.7 hrs), since the short-circuiting of flux resulting from irregular topography and vegetation was not reflected in the calculated HRT. The exit tracer concentration curves were reproduced well by both the plug flow with dispersion and tanks-in-series models, indicating that the performance of the Banwol wetland can be estimated accurately using these models.