• Title/Summary/Keyword: solid yield

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A Novel Route to New Bis(benzopyrano) Fused Dihydropyridines Using Dry Media

  • Kidwai, Mazaahir;Rastogi, Shweta;Mohan, Richa
    • Bulletin of the Korean Chemical Society
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    • v.25 no.1
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    • pp.119-121
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    • 2004
  • A new and efficient synthesis of the novel bioactive bis(benzopyrano) fused dihydropyridines is described. The conventionally developed route is a two step multicomponent condensation reaction. This is latter modified by a one pot microwave (MW) assisted reaction using inorganic solid support via the arylidene derivative intermediate. With this environmentally benign approach, the reaction time is brought down from hours to minutes along with a yield enhancement. Furthermore, the role of different solid supports is studied and it is concluded that the acidic alumina is the best solid support for the present investigation.

Production of Aerial Conidia of Lecanicillium lecanii 41185 by Solid-State Fermentation for Use as a Mycoinsecticide

  • Vu, Van Hanh;Hong, Suk-Il;Kim, Keun
    • Mycobiology
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    • v.36 no.3
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    • pp.183-189
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    • 2008
  • The production of aerial conidia of Lecanicillium lecanii 41185, a highly virulent fungus, by solid-state fermentation was studied for use as a biocontrol agent against aphids. Among several agro-industrial solid media, steamed polished rice was found to produce the highest amount of aerial conidia. The optimal conditions for aerial conidia production were determined to be a 28.5% moisture content in the rice, 25$^{\circ}C$ culture temperature, rice pH of 6.0, 75% ambient relative humidity, 4-dold seeding culture, 0.6% $KNO_3$, and 12 d of culture time. The conidia yield increased from $5.7\times10^9$ conidia/g polished rice to 18.2 $18.2\times10^9$ conidia/g polished rice following application of these optimized conditions.

Application of BMPI / HOBT Reagent in Solid-Phase Peptide Synthesis

  • Hong Nam Joo;Choi Soo Kwan;Koock Soon Uoong
    • Bulletin of the Korean Chemical Society
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    • v.10 no.1
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    • pp.19-22
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    • 1989
  • The suitability of BMPI (2-bromo-N-methyl pyridinium iodide) for solid-phase peptide synthesis was investigated. The coupling rate of BMPI/HOBT procedure. BMPI/HOBT was superior to DCC/HOBT couplings using the solid-phase peptide bond formation proceeded to a greater degree of completion than DCC/HOBT method did. Double couplings with 2 equiv. of Bocamino acids and 1.5 equiv. of BMPI and $NEt_3$ and 2 equiv. of HOBT in DMF/MC (1:1 v/v) gave the best result for the preparation of a model compound. Stepwise solid phase peptide synthesis using BMPI/HOBT procedure was successfully utilized for the preparation of $(D-Ala)^2$-dynorphine A. BMPI/HOBT procedure for the synthesis of $(D-Ala)^2$-dynorphine gave better yield (20%) than DCC/HOBT procedure did.

Etching of Al and Cu Solids by $SiCl_4$ Molecules

  • Cho Chul Hee;Lee Woan;Rhee Chang Hwan;Park Seung Chul
    • Bulletin of the Korean Chemical Society
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    • v.13 no.2
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    • pp.187-192
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    • 1992
  • The classical trajectory method, previously applied to the reactions of polyatomic molecules with fcc structured metal solids[S. C. Park, C. H. Cho, and C. H. Rhee, Bull. Kor. Chem. Soc., 11, $1(1990)]^1$ is extended to the collision energy dependence of the reaction of the Al solid by $SiCl_4$ molecules. We have calculated etching yields, degrees of anisotropy, kinetic energy distributions, and angular distributions for the reactions of the Al solid and compared with those for the reactions of the Cu solid. Over the range of collision energies we considered, the reactions of the Al soIid show higher etching yield and better anisotropy than the reactions of the Cu solid. Details of reaction mechanisms and the relevance of these calculations for the dry etching of CuAl alloy are discussed.

Estimation of Ultimate Methane Yields and Biodegradability from Urban Stream Sediments Using BMP Test (BMP(Biochemical Methane Potential) test를 통한 도심하천 퇴적물의 최종메탄발생수율 및 생분해도 산정)

  • Song, Jaehong;Kim, Seogku;Lee, Junki;Koh, Taehoon;Lee, Taeyoon
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.2
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    • pp.33-42
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    • 2010
  • The main objective of this study was to offer informations about the current conditions of stream sediments and to evaluate biochemical methane potentials of stream sediments from the urban streams in Busan city using conventional BMP tests. First we select total 5 urban streams and collect sediment samples. Then, COD, proximate analysis, volatile solid, organic carbon content and elemental analysis were conducted to determine characteristics of the sediments. Results show that COD, volatile solid and organic carbon content are determined in the range of $15.20{\sim}75.07mg\;g^{-1}$, 2.34~11.54% and 1.28~34.21%, respectively. Also, several biochemical methane potential tests were performed in a laboratory. As a result, pH values of the reactors generally increased and then stabilized at 7.11~7.35. In addition, C/N ratio, ultimate methane and carbon dioxide yield (mL/g VS) and biodegradability (%) were determined to 1.05~10.27, 10.1~179.4, 10.3~34.4 and 4.0~30.1, respectively. For the determination of the correlations between ultimate methane yield and ultimate carbon dioxide yield, C/N ratio, COD, volatile solid and organic carbon content, a linear model was fitted to the data using a least-squares algorithm. As a result, except for COD ($r^2=0.7586$) and volatile solid ($r^2=0.7876$), Linear model was well fitted to each data with good values of the correlation coefficient ($r^2=0.9795{\sim}0.9858$). Finally, we propose empirical equations, which contain C/N ratio or TOC, for the prediction of ultimate methane yield for the urban streams in Busan city.

Effects of Planting Pattern and Plant density on Seed Production of a Modified Single Cross Corn Hybrid (파종양식과 재식밀도가 옥수수 변형단교잡종 교배친의 생육 및 채종량에 미치는 영향)

  • Park, K.Y.;Kang, Y.K.;Park, S.E.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.29 no.1
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    • pp.62-66
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    • 1984
  • One row of pollen parent to two rows of seed parent (1:2), 2:4 and solid (1:2) planting patterns (PP) were compared in seed parent densities of 3,500, 5,000 and 6,500 plants per 10 ares to determine effects of PP and plant density on growths of seed and pollen plants, and seed yield of seed parent of modified single cross corn hybrid. Planting pattern did not significantly affect agronomic characteristics of seed plant except ear number per 100 plants and seed yield which were greater in solid and 1:2 PP than in 2:4 PP. Significant PP x plant density interaction did not exist for agronomic characteristics of seed parent. In the seed parent, plant height and 100 kernel weight were not affected by plant density, but ear height, ear number per 100 plants, and kernel number per ear were linearly decreased with increased plant densities. Seed yield ranged from 330 to 460 kg per 10 ares and overall yield response to plant density was quadratic. Tassel length and spikelet number per tassel of the pollen parent were significantly affected by PP and plant density. Significant PP x plant density interaction existed for tassel length and spikelet number per tassel. Tassel length and spikelet number per tassel were greater in 1:2 and 2:4 PP compared to solid PP and were greatly reduced with increased plant densities in solid and 1:2 PP. The results indicated that 1:2 or 2:4 PP at around 5,000 plants per 10 ares for seed parent would be suitable for seed production of modified single cross com hybrid.

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Characteristics on the Hot Extrusion of Semi-Solid Al-Zn-Mg Alloy (반응고 Al-Zn-Mg 합금의 고온 압출 시 특성 평가)

  • Cho, Kuk-Rae;Kim, Jeoung-Han;Yeom, Jong-Taek;Shim, Sung-Yong;Lim, Su-Gun;Park, Nho-Kwang
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.05a
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    • pp.405-408
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    • 2007
  • Semi-solid Al-Zn-Mg alloys were produced using a cooling plate method in order to investigate the extrudability. Al melt was poured on cooling plate which was adjusted at $60^{\circ}$ with respect to the horizontal plane, and the melt was cooled by water circulation underneath. Obtained Semi-solid feedstock has globular microstructure but also contains considerable amount of gas pore. Due to the pore, tensile elongation of the semi-solid feedstock was very low and it doesn't show yield point phenomenon. Isothermal hot extrusion was carried out using at $400^{\circ}C$ with a ram speed of 1mm/sec and an extrusion ratio of 25:1. The extruded bar show noticeably improved tensile ductility and strength because pore volume fraction decreased from 5% to 0.8% after extrusion. Mechanical properties of the semi-solid extruded bar were compared with that of commercial casting alloy..

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Characterization of Adsorbents for the Simultaneous Solid-Phase Extraction of Trace $\beta$-Blockers from Biological Samples (생체시료로부터 미량 $\beta$-Blockers의 동시고상추출에 사용될 흡착제들의 특성)

  • Kim, Kyoung Rae;Kim, Do Jeong
    • Analytical Science and Technology
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    • v.6 no.4
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    • pp.375-381
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    • 1993
  • The efficiencies of four different solid absorbents were evaluated for the simultaneous solid-phase extraction of six ${\beta}$-blockers from biological sample. Chromosorb 107 using methanol as the eluting solvent gave the highest solid-phase extraction yield. From the breakthrough studies of ${\beta}$-blockers, the excellent sorption and desorption properties of the Chromosorb 107 column were verified. The usefulness of Chromosorb 107/methanol was examined for the simultaneous solid-phase extraction of the ${\beta}$-blockers from serum in the concentration range of 2~8ppm.

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Characteristics on the Hot Extrusion of Semi-Solid Al-Zn-Mg Alloy (반용융 Al-Zn-Mg합금의 고온 압출 시 특성 평가)

  • Cho, Kuk-Rae;Yeom, Jong-Taek;Shim, Sung-Yong;Lim, Su-Gun;Park, Nho-Kwang;Kim, Jeoung-Han
    • Transactions of Materials Processing
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    • v.16 no.5 s.95
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    • pp.391-395
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    • 2007
  • Semi-solid Al-Zn-Mg alloys were produced by using a cooling plate method in order to investigate the extrudability. Al melt was poured on cooling plate which was adjusted at $60^{\circ}$ with respect to the horizontal plane, and the melt was cooled by water circulation underneath. Obtained Semi-solid feedstock has globular microstructure but also contains considerable amount of gas pore. Due to the pore, tensile elongation of the semi-solid feedstock was very low and it doesn't show yield point phenomenon. Isothermal hot extrusion was carried out using at $400^{\circ}C$ with a ram speed of 1mm/sec and an extrusion ratio of 25:1. The extruded bar show noticeably improved tensile ductility and strength because pore volume fraction decreased from 5% to 0.8% after extrusion. Mechanical properties of the semi-solid extruded bar were compared with that of commercial casting alloy.

Solid Culture Medium Selection Criteria for Hydroponics Farm Households (양액재배 농가의 고형배지 선택 기준에 관한 연구)

  • Kim, Dong-Seok;Kim, Dae-Young;Hwang, Jae-Hyun;Yun, Hoa-Young
    • Korean Journal of Organic Agriculture
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    • v.22 no.4
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    • pp.841-854
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    • 2014
  • This study aimed to analyze the selection criteria and priority settings for solid culture medium used in hydroponic crop production in farm households. Expert brain storming was carried out to extract solid culture medium selection criteria for hydroponic farming. As a result, 3 criteria of economy (cost), productivity, and environment, and 9 factors were extracted. A questionnaire survey of hydroponic farm households was conducted in Gyeonggi, Gangwon, and Chooncheong provinces. AHP analysis of the hydroponic solid culture medium selection criteria identified productivity as the most important criterion, chosen by 58.7% of the respondents, followed by economy (28.4%) and environment (12.9%). The 9 factors were rated by the respondents in the following decreasing order of importance: 1, crop yield (28.3%); 2, pest occurrence (18.5%); 3, maintenance/management costs (12.0%); 4, convenience of maintenance/management (13.4%); 5, initial investment cost (11.6%); 6, material energy consumption (6.5%); 7, waste recyclability (4.0%); 8, waste disposal costs (3.4%); and 9 environmental emissions (1.81%). These results imply that hydroponic farm households consider cultivation-related quality factors more important than economic factors, such as price of culture medium or installation cost.