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Improvement of Herbicide Use in Crop Production. X. Interpretations in Tank - mix Use of Aciflurofen and Haloxyfop - methyl for Weeding on Late - season Cropped Soybeans (Glycine max L.) (제초제(除草劑)의 사용법(使用法) 개발(開發)을 위한 연구(硏究) - X. 만파대두(晩播大豆)의 잡초방제(雜草防除)를 위한 Acifluorfen과 Haloxyfop-methyl의 혼용효과(混用效果) 해석연구(解析硏究))

  • Guh, J.O.;Lee, K.;Kim, D.K.;Hong, S.H.
    • Korean Journal of Weed Science
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    • v.5 no.1
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    • pp.73-84
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    • 1985
  • 25 tank-mixed combinations between Haloxyfop-methyl at 0, 0.05, 0.1, 0.15 and 0.2 kg ae/ha and Acifluorfen at 0, 0.082, 0.163, 0.245 and 0.326 kg ai/ha were applicated at post-emergence on the late-season cropped soybean(Glycine max) fields predominated by grasses and assessed on the weeding efficacy. A most abundant weed species on the experimented fields were found at September (25 species). The broadleaved weed species and sedges were successively and proportionately emerged by the control rate of grass species. From the mono-treatment of each herbicide, Haloxyfop-methyl was recognized as a highly selective one between grasses and soybean, and Acifluorfen between broadleaf weeds and soybean, respectively. By combined application with both herbicides a synergistic weeding efficacy was detected on total weed species, however antagonistic or additive on each weed groups. Among other traits of soybean, stem dry weight was influenced by weed competitions during October, number of pods per plant during August and seed yields during whole periods. For most effective and reasonable weeding, no less than 0.4 kg ai/ha of each herbicides should be applicated in combinations.

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Anatomical Difference in Selectivity between Paddy Rice and Weed Species by Mixture Use of Oxyfluorfen and Bensulfuron (Oxyfluorfen 및 Bensulfuron 조합처리(組合處理)에 의한 벼 및 수종(數種) 잡초종간(雜草種間)의 선택반응상(選擇反應相)의 해부학적(解剖學的) 비교연구(比較硏究))

  • Guh, J.O.;Chon, S.U.;Han, S.U.;Kuk, Y.I.
    • Korean Journal of Weed Science
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    • v.12 no.2
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    • pp.132-143
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    • 1992
  • The study was conducted to find out synergistic effects by interaction on the basis on anatomical changes between paddy rice and weed species by mixture use of oxyfluorfen and bensulfuron at 0, $10^{-6}$ and $10^{-4}$M, respectively. Tissues were sampled at 72 hrs after soaking treatment and prepared for light microscopic examination and sectioned longitudinally and transversely stem into $8{\mu}m$ thick. As the results of microscopic examination, the major response of treated plant involved rupture and constrict in mesophyll cells and epidermal cells, and shrinks in bundle sheath cells by oxyfluorfen and disorganization and swelling in meristems by bensulfuron. Anatomical changes in rice was the least affected by even high concentration and two herbicide mixtures, whereas Echinochloa crus-galli was severely disorganized in meristem regions and ruptured in epidermal cells by mixture use. Monochoria vaginalis was completely ruptured by any treatment concentrations and mixtures. Scirpus juncoides was considerably tolerant to both herbicides and their mixture and was similar to those that occur in rice. Perennial weed, Sagittaria pigmaea was observed vacuolation, non-nucleation of cell, and irregular cell layering but in mixture injury was slight. Cyperus serotinus was severely shrunk and ruptured by mixture treatment. Eventually anatomical variations in all weed species was shown synergistic effect by use of herbicide mixtures.

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Histopathological and Serological Observations on Experimental Anisakiasis of Rabbits (실험적 토끼 아니사키스증에서의 조직학적 병변과 혈청 항체가의 경시적 변동 양상)

  • 홍성태;이손형
    • Parasites, Hosts and Diseases
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    • v.25 no.2
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    • pp.168-180
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    • 1987
  • This study was performed to observe histopathological changes and serological reactions in chronic anisakiasis of rabbits. Each rabbit was infected per os with 30 larvae of Anisakis type I. Their sera were collected chronologically and the rabbits were killed for histopathological examination, 3, 13, 20, 30, 60, 90 and 150 days after the infection. The results were summarized as below. 1. Most of the larvae were recovered from the stomach, but a few from the omentum, intestine, mesentery and abdominal wall. The recovery rates and distribution of worms by organ were not differed by duration of infection. 2. Histologically the lesion was abscess type on 13 days, i.e., the dead worms were surrounded by fibrinous exudate, histiocytes and thick zone of numerous inflammatory cells. After 30 days, histiocytes were found to invade the worms and the lesion was changing into abscessgranulomatous type. Also a calcified worm was found on the 30th day. After then the worms were observed to be dissolved slowly until 90 days. On 150 day, only one calcified worm was observed. 3. The levels of serum IgG antibody by ELISA reached their maximum 30 days after the infection. After then, it decreased slowly until 150 days after the infection. Above serological and histopathological findings indicated that antigenic stimulation from degenerating Anisakis larvae was the greatest during the first 30 days after infection. This period was corresponding with the beginning of worm resolution or calcification. Serologic test by ELISA would be a valuable tool for confirming chronic anisakiasis.

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Changes of Visual Acuity and Ophthalmic Symptoms in Female Workers examining Silver Plating Products (은도금제품 검사실 여성근로자들의 시력변화 및 안증상)

  • Ryu, Seung-Ho;Son, Jeong-Il;Lee, Soo-Jin;Song, Jae-Cheol
    • Journal of Preventive Medicine and Public Health
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    • v.30 no.3 s.58
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    • pp.567-576
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    • 1997
  • To evaluate the effects of reflected glare on eyes, authors assessed the periodic health examination(1991-1996) & self-administered questionnaire data of a semiconductor producing company. The 13 lead frame(LF) department workers have been exposed to high reflected glare in the process for examining the silver plating products. We compared the data of connector(14) and clerical(12) workers as the non-exposed ones. Among LF department workers, 100% felt their visual acuity worsened(connector:81.8%, clerical:85.7%), and 70% had worn the glasses o. contact lenses(connector : 14.3%, clerical :40%) since working at the company. Major ophthalmic symptoms of the LF workers are asthenopia, tearing, decreased visual acuity, congestion and glare. Decrease of visual acuity by Hahn's line change of the LF workers is significantly high during a 5-year follow-up(p<0.05 by simple regression) compared with connector clerical workers.

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Evaluation on Heating Effects of Geothermal Heat Pump System in Farrowing House (지열 난방시스템을 이용한 분만돈사의 난방효과 분석)

  • Choi, H.C.;Park, Jae-Hong;Song, J.I.;Na, J.C.;Kim, M.J.;Bang, H.T.;Kang, H.G.;Park, S.B.;Chae, H.S.;Suh, O.S.;Yoo, Y.S.;Kim, T.W.
    • Journal of Animal Environmental Science
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    • v.16 no.3
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    • pp.205-215
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    • 2010
  • Geothermal heat pump system (GHPS) is an energy-efficient technology that use the relatively constant and renewable energy stored in the earth to provide heating and cooling. With the aim of using GHPS as a heating source, it's possibilities of application in farrowing house were examined by measuring environmental assessment and sow's performance. A total of 96 sows were assigned to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in winter season. During the experimental period, indoor maximum temperature in GHPS-housing was measured up to $26.7^{\circ}C$, average temperature could maintain $21.2^{\circ}C$. The mean value of dust levels and $CO_2$, $NH_3$ and $H_2S$ gas emissions were decreased in GHPS-housing compare with those of conventional housing. Litter size, birth weight, parity and weaning weight did not differ between housings. However, feed intake of sow in GHPS-housing was lower than that of conventional housing. In energy consumption for heating, electric power consumption increased in GHPS-housing than the conventional housing, a 2,250 kwh increase, whereas there is no fuel usage for heater in GHPS-housing. Amount of ground water circulated for heating in cold weather for earth heat exchanger was 8.4-12.9 ton per day. In conclusion, GHPS may have environmental benefits and effectiveness of heating in farrowing housing and affect the performance in sows.

Changes in Moisture Contents of Rice-hull Based Root Media and Growth Responses of 'Seolhyang' Strawberry during Vegetative Propagation (육묘 과정 중 포트에 충진된 팽연왕겨 혼합상토의 함수량 변화와 '설향' 딸기의 생장 반응)

  • Park, Gab Soon;Kim, Yeoung Chil;Ann, Seoung Won;Kang, Hee Kyoung;Choi, Jong Myung
    • Horticultural Science & Technology
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    • v.33 no.1
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    • pp.47-54
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    • 2015
  • This research was conducted to investigate the changes in moisture retention capacities of expanded rice-hull (ERH)-based root media and their influences on the growth of mother and daughter plants in vegetative propagation of 'Seolhyang' strawberry. The proportion of water at the container capacity of ERH medium was in the range of 20 to 23%. This range was lower than the 60 to 66% of strawberry-specialized medium, the 30 to 34% of soil mother material (SMM) and the 30 to 35% of loamy sand. The moisture content of ERH was reduced to 10 to 12% at 8 hours after irrigation, and there were large variations among replications of ERH medium. Among four kinds of root media formulated to contain ERH, the medium of ERH + coir dust (CD) (55 + 45%, v/v) had 26.5 and 32.5% water contents at 20 and 40 days after irrigation to daughter plants, respectively. The m edia o f ERH + sandy loam (S L) and E RH + S MM showed similar trends i n moisture r etention. The pH and EC i n the all root media tested were in the range of 6.7 to 7.1 and 0.03 to $0.08dS{\cdot}m^{-1}$, respectively. The pHs and ECs measured at 20 and 40 days after irrigation were not significantly different in each root medium. Among the root media formulated to contain ERH, the growth of daughter plants was the highest in the treatment of ERH + SL (55 + 45%, v/v). As the blending rate of coir dust was elevated in the ERH + CD media, moisture retention capacity increased gradually, but the growth of daughter plants became worse even though the medium showed higher moisture retention capacity than other root media tested. The growth of roots and aboveground tissues of daughter plants deteriorated in the root media formulated by blending ERH + perlite (PE) at various ratios. The results of this research suggest the optimum formulations of root media and management of moisture content in raising of strawberry daughter plants when ERH is a component of root media.

Effects of Extraction Conditions on the Functional Properties of Garlic Extracts (추출조건이 마늘 추출액의 기능성에 미치는 영향)

  • Byun, Pyung-Hwa;Kim, Woo-Jung;Yoon, Suk-Kwon
    • Korean Journal of Food Science and Technology
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    • v.33 no.5
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    • pp.507-513
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    • 2001
  • An effective extraction methods of a garlic were investigated in order to improve the functional properties of the extracts. The solid yield, electron donating ability (EDA), nitrite-scavenging effects (NSE), peroxide value (POV) and total thiosulfinates contents of garlic extracts were determined. In order to improve the functional properties of extracts prepared with several organic solvents and acids, concentration and pH adjustment of the selected solvent and addition of acids and salts to solvents were also examined. Among the solvents tested, the methanol and ethanol extracts were found to be the most effective on the base of functionality and solid yields. The highest EDA, NSE and thiosulfinate value were obtained with 50% ethanol. The pH control of solvent and addition of citric acid, NaCl and phosphates to 50% ethanol did not affect on the functionality of the extracts. Therefore the optimal solvent for the best functional properties of garlic extract was 50% ethanol.

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Effect of the Particle Size and Unburned Carbon Content on the Separation Efficiency of Fly ash in the Countercurrent Column Flotation (向流컬럼浮選機에서 石炭灰의 크기 및 未燃炭素 含量이 分離特性에 미치는 영향)

  • 이정은;이재근
    • Resources Recycling
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    • v.9 no.6
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    • pp.36-44
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    • 2000
  • Fly ash was composed of the unburned carbon and mineral particles. The former was able to attach on the bubbles, while the latter was not. Therefore, it was possible to separate the unburned carbon and the mineral from fly ash using the froth flotation process. This study was carried out to evaluate the separation efficiency as a function of the ny ash particle properties in the column flotation. Separation efficiency was analyzed for various size fraction of -38 fm,38~125 fm and 1125 W, and for various fly ash samples containing 7, 11, and 20 wt% unburned carbon. For the size fractions of -38 fm containing 7 wt% unburned carbon, separation efficiency was 86ft, whereas separation efficiency was found to be 74% for the size fraction of +125$\mu\textrm{m}$ containing 20 wt% unburned carbon. The results indicated that separation efficiency increased with the decrease in the particle size and the unburned carbon content of the fly ash.

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Variation of Indoor Air Temperature by using Hot Water Piping in Greenhouse (온수배관에 의한 온실 내부의 온도변화)

  • Yoon, Yong-Cheol;Shin, Yik-Soo;Bae, Seoung-Beom;Kim, Hyeon-Tae;Choi, Jin-Sik;Suh, Won-Myung
    • Journal of agriculture & life science
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    • v.46 no.2
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    • pp.179-190
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    • 2012
  • This study was performed to obtain a heat saving effect and enhance the efficiency of a greenhouse by using a hot water piping in order to minimize the operating costs of a greenhouse as oil prices continue to rise. This method also reduces the likelihood of accidents caused by snowdrifts in regions with heavy snowfall. In general, the experimental plot was $2.0{\sim}6.0^{\circ}C$ higher than the control plot. When the skylight felt was opened, the minimum temperature was in the range of $3.0{\sim}12.0^{\circ}C$. Therefore, we judged that damage caused by snowdrifts may be prevented partly by active heating. The temperature difference inside of the greenhouse by height was insignificant. The maximum heating load of the greenhouse according to crop was respectively about $37,000kcal{\cdot}h^{-1}$ and $41,700kcal{\cdot}h^{-1}$. During the experiment, the heat value of each designed temperature in the range of the minimum ambient temperature $-11.9{\sim}4.0^{\circ}C$ was about 95,000~322,000 kcal and it was in the range of $6,050{\sim}20,900kcal{\cdot}h^{-1}$. If it is compared with the maximum heating load, it can be shown that about 15~56% of the heating energy can be supplied. The total heat value and the amount of power consumption were 2,629,025 kcal and 677.3 kWh respectively during the experiment. If it is heated with diesel, a fossil fuel, the consumption during the experiment was 291 L and the cost was 331,700won. Total cost of using electric power was about 24,400 won and it is shown that it is about 7.5% of the cost of diesel consumption. Also, if the total amount of power consumption is converted into energy, it is approximately 582,200 kcal and the energy was just about 22% of the total heat value.

Comparison of antioxidant capacity of protein hydrolysates from 4 different edible insects (식용곤충별 단백가수분해물의 항산화 활성 비교)

  • Jang, Hyun-Young;Park, Chae-Eun;Lee, Syng-Ook
    • Korean Journal of Food Science and Technology
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    • v.51 no.5
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    • pp.480-485
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    • 2019
  • The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.