• Title/Summary/Keyword: $H_2S$ yield

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Identification of Synthesized Pitch Derived from Pyrolyzed Fuel Oil (PFO) by Pressure (석유계 잔사유(PFO)의 피치 합성 시 압력조건에 따른 피치 특성 변화)

  • Seo, Sang Wan;Kim, Ji Hong;Lee, Young-Seak;Im, Ji Sun
    • Applied Chemistry for Engineering
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    • v.29 no.6
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    • pp.652-656
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    • 2018
  • In this study, effects of the reaction pressure were studied for petroleum-based pitch synthesis. A two-stage reaction process was performed based on different reaction pressure conditions. Each stage experiments for the two-stage reaction were consecutively carried out. The first stage was consisted of three different pressure conditions; high (10 bar), normal and low (0.1 bar). And the second stage was carried out at the normal and low (0.1 bar) pressure. The pitch synthesis was realized at $400^{\circ}C$ for 2 h. Thermal properties and molecular weight distributions of each samples were investigated by analyzing the softening point and MALDI-TOF data. Volatilized components during the pith synthesis were measured by GC-SIMDIS. In case of the first-step reaction with the high pressure condition, the low molecular weight component participated to the pitch formation more effectively and the pitch with the low softening point was obtained. However, for the case of the first-step with the low pressure, the low molecular weight component was vent outside and the partial coke formation occurred. Eventually, pitch properties such as the softening point and yield were controlled effectively by changing the pressure in the pitch synthesis reaction.

National Genetic Evaluation (System) of Hanwoo (Korean Native Cattle)

  • Park, B.;Choi, T.;Kim, S.;Oh, S.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.2
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    • pp.151-156
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    • 2013
  • Hanwoo (Also known as Korean native cattle; Bos taurus coreanae) have been used for transportation and farming for a long time in South Korea. It has been about 30 yrs since Hanwoo improvement began in earnest as beef cattle for meat yield. The purpose of this study was to determine the trend of improvement as well as to estimate genetic parameters of the traits being used for seedstock selection based on the data collected from the past. Hanwoo proven bulls in South Korea are currently selected through performance and progeny tests. National Hanwoo genetic evaluations are implemented with yearling weight (YW), carcass weight (CW), eye muscle area (EMA), backfat thickness (BF) and marbling score (MS). Yearling weights and MS are used for selecting young bulls, and EMA, BF, and MS are used for selecting proven bulls. One individual per testing room was used for performance tests, and five individuals per room for progeny tests. Individuals tested were not allowed to graze pasture, but there was enough space for them to move around in the testing room. Feeds including roughages and minerals were fed ad libitum, and concentrates were provided at the rate of about 1.8% of individual weight. Overall means of the traits were $352.8{\pm}38.56$ kg, $335.09{\pm}44.61$ kg, $77.85{\pm}8.838\;cm^2$, $8.6{\pm}3.7$ mm and $3.293{\pm}1.648$ for YW, CW, EMA, BF and MS. Heritabilities estimated in this study were 0.30, 0.30, 0.42, 0.50 and 0.63 in YW, CW, EMA, BF and MS, respectively, which are similar to results from previous research. Yearling weight was 315.54 kg in 1998, and had increased to 355.06 kg in 2011, resulting in about 40 kg of improvement over 13 yrs. YW and CW have improved remarkably over the past 15 yrs. Breeding values between 1996 and 2000 decreased or did not change much, but have moved in a desirable direction since 2001. These improvements correspond with the substantial increase in use of animal models since the late 1990s in Korea. Hanwoo testing programs have practically contributed to the improvement in aspects of quality and quantity. In sum, the current selection system is good enough to accommodate circumstances where fewer sires are used on many more cows. Although progeny tests take longer and cost more, they seem to be appropriate under the circumstances of the domestic market with its higher requirement for better meat quality. Consequently, accumulative data collection, genetic evaluation model development, revision of selection indices, as well as cooperation among farms, associations, National Agricultural Cooperative Federation, universities, research institutes, and government agencies must be applied to the Hanwoo selection program. All these efforts will assist the domestic market to secure a competitive position against imported beef under Free Trade Agreement trade system and will provide farmers with higher profits as well as the public with a higher quality of beef.

Physicochemical Properties of Dextran Produced by Leuconostoc mesenteroides SM according to Concentration of Yeast Extract and its Modulation of Rheological Properties (효모 추출물 농도에 따른 Leuconostoc mesenteroides SM에 의해 생산된 dextran의 물리화학적 특성 및 물성개량)

  • Kim, Ji-Eun;Whang, Key;Lee, Sam-Pin
    • Korean Journal of Food Science and Technology
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    • v.44 no.2
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    • pp.216-223
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    • 2012
  • Dextran was produced by $Leuconostoc$ $mesenteroides$ SM with various contents of yeast extract and its rheological properties were modulated, via an addition of hydroxypropyl methylcellulose (HPMC) of different viscosities. The conversion yield reached 90% after adding 3% yeast extract, which remained constant, thereafter. The acidity of the cultures was approximately 1.4 and 0.9% after fermentation for 24 h at 25 and $30^{\circ}C$, respectively. The total dextran content (107.3 g/kg) was the highest in the presence of the 3% yeast extract. Under the same conditions, the consistency, viscous modulus (G"), and elastic modulus (G') of the cultures were $37.6\;Pa{\cdot}s^n$, 38 Pa, and 50 Pa, respectively. The rheological properties of the culture were changed drastically by the fortification with HPMC of higher concentration and viscosity. The addition of 10% HPMC (4,000 cp) resulted in a significant increase in G" to 1,950 Pa. Furthermore, adding HPMC to a viscous culture resulted in a remarkable increase in both hardness and firmness.

Characterization of Bacteriocin Produced from Isolated Strain of Bacillus sp. (Bacillus 속 분리주가 생산하는 박테리오신의 특성 조사)

  • Ham, Seung-Hee;Choi, Nack-Shick;Moon, Ja-Young;Baek, Sun-Hwa;Lee, Song-Min;Kang, Dae-Ook
    • Journal of Life Science
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    • v.27 no.2
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    • pp.202-210
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    • 2017
  • As an effort to find a potential biopreservative, we isolated bacterial strains producing bacteriocin from fermented foods. A strain was finally selected and characteristics of the bacteriocin were investigated. The selected strain was identified as Bacillus subtilis E9-1 based on the 16S rRNA gene analysis. The culture supernatant of B. subtilis E9-1 showed antimicrobial activity against Gram-positive bacteria. Subtilisin A, ${\alpha}$-chymotrypsin, trypsin and proteinase K inactivated the antimicrobial activity, which means its proteinaceous nature, a bacteriocin. The bacteriocin activity was fully retained at the pH range from 2.0 to 8.0 and stable at up to $100^{\circ}C$ for 60 min. Solvents such as ethanol, isopropanol and methanol had no effect on the antimicrobial activity at the concentration of 100% but acetone and acetonitrile reduced the activity at up to 100% concentration. Cell growth of four indicator strains was dramatically decreased in dose-dependent manner. Listeria monocytogenes was the most sensitive, but Enterococcus faecium was the most resistant. Bacillus cereus and Staphylococcus aureus showed the medium sensitivity. The bacteriocin showed its antimicrobial activity against B. cereus and L. monocytogenes via bactericidal action. The number of viable cells of L. monocytogenes started to reduce after addition of bacteriocin to the minced beef. The bacteriocin was purified through acetone concentration, gel filtration chromatography and RP-HPLC. The whole purification step led to a 6.82 fold increase in the specific activity and 6% yield of bacteriocin activity. The molecular weight of the purified bacteriocin was determined to be 3.3 kDa by MALDI-TOF/TOF mass spectrometry.

Application of the Trickling Rice Straw Filter Medium for Livestock Wastewater Enhanced Soil Chemical Properties and the Growth of Orchard Grass (Dactylis glomerata L.) (축산폐수(畜産廢水) 살수여상충전(撒水濾床充塡) 볏짚 시용이 토양화학성과 오처드그래스(Dactylis glomerata L.)의 생육에 미치는 영향(影響))

  • Kim, Jeong-Je;Yang, Jae-E;Shin, Young-Oh;Shin, Myung-Kyo
    • Korean Journal of Soil Science and Fertilizer
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    • v.30 no.4
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    • pp.334-340
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    • 1997
  • It was proven that rice straw can serve can serve as a good support medium for trickling filter with livestock wastewater treatment. The efficiency of removal of removal of environmentally undesirable components from the wastewater by the straw medium was no less inferior to other commonly used support materials. The treated straw was also proven to be a source of abundant plant nutrients. The growth of orchard grass was enhanced greatly by the application of large quantity of the support medium. A maximum yield of dry matter was obtained at the rate of 40 ton/ha. Inorganic NPK elements as background fertilizers were highly recommended for better development in an early stage of growth. The nutritional status of the soil was very much improved by the addition of the medium in terms of exchangeable cations(K, Ca, Mg and Na), available phosphate, and organic matter contents. Nutrient uptake by orchard grass such as N, P and cations was enhanced by rice straw medium treatment and that was proportional to the levels of treatment.

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Establishment of Control System of Weedy Rice(Oryza sativa) and Barnyardgrass(Echinochloa crus-galli) in Direct-seeded Rice - I. Effect of Oxadiazon, Molinate, Thiobencarb on Control of Red Rice and Barnyardgrass in Water-seeded Rice (벼 직파재배에 있어서 잡초성벼 및 피 방제체계 확립에 관한 연구 - I. 담수표면산파 재배시 앵미와 피에 대한 oxadiazon, molinate, thiobencarb의 파종전 처리 효과)

  • Ryang, H.S.;Kim, J.K.;Kyoung, E.S.;Kim, J.S.;Ma, S.Y.
    • Korean Journal of Weed Science
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    • v.18 no.2
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    • pp.106-115
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    • 1998
  • This study was conducted to investigate the effect of oxadiazon, molinate, thiobencarb before seeding on control of red rice and barnyardgrass in water-seeded rice. High application rate plot among oxadiazon treatment plots could observe phytotoxicity symptoms depending on field conditions, but these injury recovered gradually with time. Molinate and thiobencarb application plots at the concentration of 225~400, 210~420g ai/l0a respectively were not observed phytotoxicity. Control of red rice was different according to kinds of herbicides and application rates. Oxadiazon showed higher control performance at the concentration of more than 60g ai/10a. Control effect of molinate and thiobencarb against red rice was enhanced with the increase of application rate, and both herbicides showed satisfactory effect at more than 300g ai/10a. Control of barnyardgrass showed up to 90~100% in all tested herbicides. There was no significant yield reduction by oxadiazon, molinate, and thiobencarb application before seeding in all tested field. In the pot experiment, crop injury, seedling stand, and early growth were more advantageous at time of drainge after one day after seeding than flooding until rooting.

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Effect of a Combined Treatment with Uniconazole, Silver Thiosulfate on Reduction of Ozone Injury in Tomato Plant (Uniconazole 과 Silver Thiosulfate 의 복합처리가 토마토의 오존피해경감에 미치는 효과)

  • Ku, Ja-Hyeong;Won, Dong-Chan;Kim, Tae-Il;Krizek, Donld T.;Mirecki, Roman M.
    • Korean Journal of Environmental Agriculture
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    • v.11 no.1
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    • pp.50-58
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    • 1992
  • Studies were conducted to determine the combined effect of uniconazole [(E) -1-(4-chlorophenyl)-4, 4-demethyl 2-(1,2,4 triazol-1-yl)-1-penten-3-ol] and silver thiosulfate $[Ag {(S_2O_3)}^3\;_2-]$ (STS) on reduction of ozone injury in tomato plants(Lycopersicon esculentum Mill. 'Pink Glory'). Plants were given a 50ml soil drench of uniconazole at concentrations of 0, 0.001, 0.01 and 0.1 mg/pot at the stage of emerging 4th leaf. Two days prior to ozone fumigation, STS solution contained 0.05% Tween-20 was also sprayed at concentrations of 0, 0.3 and 0.6 mM. Uniconazole at 0.01 mg/pot and STS at 0.6 mM were effective in providing protection against ozone exposure(20h at 0.2ppm) without severe retardation of plant height and chemical phytotoxicity, respectively. Combined treatment with uniconazole, STS significantly reduced ozone injury at the lower concentration than a single treatment with uniconazole or STS. Uniconazole treatment reduced plant height, stem elongation and transpiration rate on a whole plant level and increased chlorophyll concentration. STS did not give any effect on plant growth and chlorophyll content but increased transpiration rate in non-ozone-fumigated plants. Ethylene production in the leaves of ozone-fumigated plants was decreased by uniconazole and STS pretreatment, but there was no protective effect on epinasty of leaves in uniconazole-treated plants. STS increased ethylene production in non-ozone-fumigated plants, but it significantly reduced the degree of epinasty and defoliation of cotyledons when plants were exposed to ozone. Uniconazole slightly increased superoxide dismutase and peroxidase activities. But STS showed little or no effects on such free radical scavengers. Day of flowering after seeding was shortened and percentages of fruit set were increased by uniconazole treatment. STS was highly effective on protecting reduction of fruit set resulting from ozone fumigation. These results suggest that combined use of uniconazole and STS should provide miximum protection against ozone injury without growth retardation resulting in yield loss.

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Efficient (3R)-Acetoin Production from meso-2,3-Butanediol Using a New Whole-Cell Biocatalyst with Co-Expression of meso-2,3-Butanediol Dehydrogenase, NADH Oxidase, and Vitreoscilla Hemoglobin

  • Guo, Zewang;Zhao, Xihua;He, Yuanzhi;Yang, Tianxing;Gao, Huifang;Li, Ganxin;Chen, Feixue;Sun, Meijing;Lee, Jung-Kul;Zhang, Liaoyuan
    • Journal of Microbiology and Biotechnology
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    • v.27 no.1
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    • pp.92-100
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    • 2017
  • Acetoin (AC) is a volatile platform compound with various potential industrial applications. AC contains two stereoisomeric forms: (3S)-AC and (3R)-AC. Optically pure AC is an important potential intermediate and widely used as a precursor to synthesize novel optically active materials. In this study, chiral (3R)-AC production from meso-2,3-butanediol (meso-2,3-BD) was obtained using recombinant Escherichia coli cells co-expressing meso-2,3-butanediol dehydrogenase (meso-2,3-BDH), NADH oxidase (NOX), and hemoglobin protein (VHB) from Serratia sp. T241, Lactobacillus brevis, and Vitreoscilla, respectively. The new biocatalyst of E. coli/pET-mbdh-nox-vgb was developed and the bioconversion conditions were optimized. Under the optimal conditions, 86.74 g/l of (3R)-AC with the productivity of 3.61 g/l/h and the stereoisomeric purity of 97.89% was achieved from 93.73 g/l meso-2,3-BD using the whole-cell biocatalyst. The yield and productivity were new records for (3R)-AC production. The results exhibit the industrial potential for (3R)-AC production via whole-cell biocatalysis.

Control of Spiderwort(Aneilema keisak Hassk) in No-tillage Rice (벼 무경운재배(無耕耘栽培)에 있어서 효과적(效果的)인 사마귀풀(Aneilema keisak Hassk) 방제(防除))

  • Kwon, O.D.;Shin, H.R.;Park, T.D.;Guh, J.O.;Lim, J.S.
    • Korean Journal of Weed Science
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    • v.16 no.2
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    • pp.100-107
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    • 1996
  • Pre- and post-emergent control of Aneilema keisak was investigated in no-till paddy fields. In addition, a pot trial was conducted to determine use rates of the experimental post-emergent herbicide LGC40863. For pre-emergent control, butachlor(1,800g ai/ha), pretilachlor(600g ai/ha), pretilachlor plus pyrazosulfuron(300+18g ai/ha, respectively), thiobencarb plus bensulfuron(2,100+51g ai/ha, respectively), and molinate plus pyrazosulfuron(1,500+21g ai/ha, repectively) were treated at 20 days before seeding. Among the herbicides, molinate plus pyrazosulfuron was the least effective (23% control), while all other herbicides provided excellent(>95%) control of A. keisak. None of these herbicides caused rice phytotoxicity. However, rice yield in the plot treated with molinate plus pyrazosulfuron decreased about 50% due to poor A. keisak control. LGC40863 controlled A. keisak completely, by foliar application, across wide growth stages from the 5- to 15-leaf at 50g ai/ha in pot tests. In the field, treatment of LGC40863(30 to 50g ai/ha) provided >95% control of A. keisak when treated either at 15 days after transplanting or at non-productive tillering stage. Efficacy of 2,4-D and bentazon was insufficient when treated at non-productive tillering stage. These results suggest that, in no-till paddy fields, A. keisak is controlled by pre-emergent application of butachlor, pretilachlor, pretilachlor plus pyrazosulfuron, or thiobencarb plus bensulfuron, and by post-emergent application of LGC40863.

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Effect of Compost Application on Yield and Chemical Components of Chinese Cabbage(Brassica pekinensis Rupr.) and Changes of Soil Physico-chemical Properties in Organic Farming (유기농산물 생산을 위한 퇴비시용이 배추의 수량과 무기성분 및 토양의 이화학성에 미치는 영향)

  • Lee, Joo-Sam;Chang, Ki-Woon;Cho, Sung-Hyun;Kim, Chong-Yun
    • Korean Journal of Soil Science and Fertilizer
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    • v.29 no.4
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    • pp.365-370
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    • 1996
  • To get the basic data for organic farming, the Chinese cabbage(Brassica pekinensis Rupr.) was cultivated in field of sandy loam soil and compost was applied at the ratios of 0, 20, 40, 80, 120ton per ha, respectively, with N-P-K elements. The yield of Chinese cabbage was maximum in the plot of compost 40t/ha application and it's weight was 3,783g/head. The chemical components of Chinese cabbage were no remarkable changes with the increasing amount of compost application. Content of organic matter in soil after experiment was finished was 39g/kg, total nitrogen was 2.2g/kg, available phosphorus was 1,927mg /kg. CEC was $11.4cmol^+/kg$, exchangable cations were K:0.5. Ca:0.6. Mg:0.3 and $Na:0.2cmol^+/kg$ in treatment of compost 120 t/ha.

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