• Title/Summary/Keyword: 합성율

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A new formulation method of small amount wettable powders for pesticide screening (농약스크리닝을 위한 미량 수화제의 간편한 제제방법)

  • Yu, Ju-Hyun;Lee, Byung-Hoi;Cho, Kwang-Yun
    • Applied Biological Chemistry
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    • v.33 no.4
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    • pp.315-318
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    • 1990
  • After technical pesticides and dispersants were dissolved in a volatile organic solvent, the wettable powders(WP's) were formulated by adsorbing the pesticide-dispersant solution to finely powdered porous synthetic silica without milling process. The median sizes of 11 WP'S were smaller than $8{\mu}m$, 9 of which had more than 80% suspensibility after 2 hours. It was possible In formulate 50% WP for liquid of fly technical pesticides. The pesticidal efficacies of WP's tested were comparable In commercial formulations regardless of suspensibilities of WP's.

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A Study on Delta Pitch Searching of CELP Vocoder using the Symmetry of Correlation (상관관계 대칭성을 이용한 CELP 보코더의 델타피치 검색에 관한 연구)

  • Jung Hyun Uk;Min So Yeon;Bae Myung Jin
    • Proceedings of the Acoustical Society of Korea Conference
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    • autumn
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    • pp.119-122
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    • 2004
  • G.723.1은 저 전송률 환경에서 고 음질을 제공하여 주고 있으나 CELP형 부호화기가 갖는 합성에 의한 분석(Analysis by Synthesis)방식의 구조로 인해 많은 처리 시간과 계산량을 요구하게 된다. 본 논문에서는 G.723.1에 대해 NAMDF함수를 적용하여 델타 피치 검색과정의 계산량을 줄여 부호화기의 전체 계산량을 감소시키는 방법을 제안하였다. 기존의 피치 검출 알고리즘에서 피치 검출을 위해 사용하고 있는 자기상관함수는 곱셈 연산에서 발생하는 bit의 dynamic range가 커서 나눗셈 연산에서도 과도한 연산량을 필요로 한다. 따라서, 이러한 계산량의 감소를 위해 기존의 자기상관함수 대신 계산량을 감소하기 위하여 NAMDF 방법을 적용하였고 추가된 skipping 기법을 사용하였다. 계산량 감소율 측면에서는 약 $64\%$의 감소율을 보였고 기존의 방법과 제안한 방법간의 피치 pitch contour은 원음성의 피치 contour와 유사하였고, 음질 평가에서도 기존의 G.723.1 부호화기 합성음과 유사한 길과를 얻을 수 있었다.

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Characteristics of Heteropoly Acid Catalyst for the Synthesis of ETBE(Ethyl Tert-Butyl Ether) (ETBE(Ethyl Tert-Butyl Ether) 합성에 대한 헤테로폴리산 촉매의 특성)

  • Park, Nam-Cook;Shin, Jae-Soon;Seo, Seong-Gyu;Lim, Yeoung-Taek;Kim, Jae-Seung
    • Applied Chemistry for Engineering
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    • v.5 no.1
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    • pp.30-36
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    • 1994
  • Reaction characteristics and correlations between the acidic property and catalytic activity of heteropoly acid catalyst on ETBE synthesis as a gasoline octane enhancer were investigated. The amount of pyridine adsorbed on heteropoly acid catalyst and catalytic activity in the synthesis of ETBE showed a good correlation. But ammonia failed to show such a correlation because of the complex formation of ammonia adsorbed and transition metal ions. In the case of supported catalyst catalytic activity and product distribution were mainly affected by the adsorption characteristics of TBA or iso-butene.

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Vitellogenin Induction by Rainbow trout (Oncorhynchus mykiss) Hepatocytes in Primary Culture (무지개송어의 간세포 초대배양에 의한 Vitellogeinin 합성 유도)

  • 여인규
    • Journal of Aquaculture
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    • v.11 no.4
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    • pp.557-564
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    • 1998
  • Vitellogenin (VTG) induction in response estradiol-17${\beta}$ ($E_2$) were electrophoretically examined in primary hepatocyte cultures in rainbow trout. The hepatocytes were maintained as monolayers on positively charged dishes for up to 7 days. The viability of hepatocytes on Day 7 in cultures decreased about 20.7% and 23.6% with and without $E_2$, respecitively. The amount of DNA per dish also decreased to 13.7% and 14.0% with and without $E_2$, respectively. There were no differences in viability and DNA content between the control and $E_2$-treated culture. Moreover, the rate of VTG to total protein concentrations reached the maxium level at the addition of $10^{-6}$ M E2, to the incubation medium. However, the higher concentration of $10^{-5}$ M $E_2$ rater depressed the level.

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The Facile Synthesis of N-Substituted 2,5-Dimethylpyrrolidine Derivatives from 2,5-Hexanedione and a Variety of Primary Amines using Tetracarbonylhydridoferrate(O) as a Selective Reducing Agent (II) (선택적 환원시약인 사카르보닐 철산염(O)을 이용한 N-치환-2,5-디메틸 피로리딘 유도체의 용이한 합성)

  • Sang Chul Shim;Keun Tai Huh;Kee Doo Kim;Woo Sik Kim
    • Journal of the Korean Chemical Society
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    • v.30 no.4
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    • pp.389-393
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    • 1986
  • The reaction of 2,5-hexanedione with a variety of primary amines using tetracarbonylhydridoferrate(O) as a selective reducing agent at room temperature or 60${\circ}C$ under an atmosphere of carbon monoxide gave the corresponding N-substituted 2,5-dimethylpyrrolidine derivatives. The reaction of synthesized 5-nitro-2-hexanone with benzaldehyde in the presence of tetracarbonylhydridoferrate(O) at 150${\circ}C$ under an atmosphere of carbon monoxide in an autoclave also gave N-benzyl-2,5-dimethylpyrrolidine in moderate yield. The mechanism of these reactions was investigated.

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Multi-site based earthquake event classification using graph convolution networks (그래프 합성곱 신경망을 이용한 다중 관측소 기반 지진 이벤트 분류)

  • Kim, Gwantae;Ku, Bonhwa;Ko, Hanseok
    • The Journal of the Acoustical Society of Korea
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    • v.39 no.6
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    • pp.615-621
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    • 2020
  • In this paper, we propose a multi-site based earthquake event classification method using graph convolution networks. In the traditional earthquake event classification methods using deep learning, they used single-site observation to estimate seismic event class. However, to achieve robust and accurate earthquake event classification on the seismic observation network, the method using the information from the multi-site observations is needed, instead of using only single-site data. Firstly, our proposed model employs convolution neural networks to extract informative embedding features from the single-site observation. Secondly, graph convolution networks are used to integrate the features from several stations. To evaluate our model, we explore the model structure and the number of stations for ablation study. Finally, our multi-site based model outperforms up to 10 % accuracy and event recall rate compared to single-site based model.

Simultaneous Determination of Residual Synthetic Antimicrobials in Animal Muscles by High Performance Liquid Chromatography (액체 크로마토그라피를 이용한 동물 근육조직 중의 합성항균제 동시 분석)

  • 정규생;채명식;김창동;김종배
    • Journal of Food Hygiene and Safety
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    • v.8 no.1
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    • pp.25-35
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    • 1993
  • This study is conducted to deyelop more conyenient simultaneous determination method by HPLC for mixed antimicrobial agents (sulfamerazine; SMR, sulfamethazine; SMT, sulfamonomethoxine; SMMX, sulfadimethoxine; SDMX, sulfaquinoxaline; SQX, furazolidone; FZ, zolene; ZOL and ethopabate; EPB in muscles of boline, pork and chicken. The drugs were extracted by dichloromethane and water. The extract, after solyent eyaporation, was partitioned in hexane/water and water/dichloromethane. The dichloromethane layer was filtrated with anhydrous $Na_5S0_4\;in\;_3G_3$ glass filter and was eyaporated to dryness. The residue was dissoIYed in mobile phase. The test solution analyzed by HPLC. The chromatograpic conditions were as follows; Column-Spheri 5 RP-8($4.6{\times}220,\;5\;{\mu}$), Wayelength-270 nm, Mobile phase-acetonitrile: 0.005 M oxalic acid (22 : 78). The ayerage recoyeries of drugs from muscles of boline, pork and chicken spiked standard solution were approximately 74~99%, 73~99% and 75~96%, respectiyely. The limits of detection were 5 ppb for SMR, SMT, SMMX, SDMX and EPB, and 8 ppb for SQX, FZ and ZOL.

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Direct Synthesis of Dimethyl Ether from Synthesis Gas (합성가스로부터 디메틸에테르 직접 합성)

  • Hahm, Hyun-Sik;Kim, Song-Hyoung;Kang, Young-Gu;Shin, Ki-Seok;Ahn, Sung-Hwan
    • Journal of the Korean Institute of Gas
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    • v.13 no.4
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    • pp.8-14
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    • 2009
  • Dimethyl ether(DME) was synthesized from synthesis gas by a one-step process in which a hybrid catalyst was used. The hybrid catalyst consisted of Cu-ZnO-$Al_2O_3$ for the methanol synthesis reaction and aluminum phosphate or $H_3PO_4$-modified $\gamma$-alumina for the methanol dehydration reaction. The prepared catalysts were characterized by XRD, BET, SEM, FT-IR and $NH_3$-TPD. From the XRD analysis, it was verified that the aluminum phosphate was successfully synthesized. The specific surface areas of the synthesized aluminum phosphates were varied with the ratio of P/Al. The hybrid catalyst in which P/Al ratio of the aluminum phosphate was 1.2 showed the highest CO conversion of 55% and DME selectivity of 70%. There was no remarkable decrease in catalytic activity with the phosphoric acid treatment of $\gamma$-alumina. However, when treated with concentrated phosphoric acid(85%), the catalytic activity and DME selectivity decreased.

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Multi-view Synthesis Algorithm for the Better Efficiency of Codec (부복호화기 효율을 고려한 다시점 영상 합성 기법)

  • Choi, In-kyu;Cheong, Won-sik;Lee, Gwangsoon;Yoo, Jisang
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.2
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    • pp.375-384
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    • 2016
  • In this paper, when stereo image, satellite view and corresponding depth maps were used as the input data, we propose a new method that convert these data to data format suitable for compressing, and then by using these format, intermediate view is synthesized. In the transmitter depth maps are merged to a global depth map and satellite view are converted to residual image corresponding hole region as out of frame area and occlusion region. And these images subsampled to reduce a mount of data and stereo image of main view are encoded by HEVC codec and transmitted. In the receiver intermediate views between stereo image and between stereo image and bit-rate are synthesized using decoded global depth map, residual images and stereo image. Through experiments, we confirm good quality of intermediate views synthesized by proposed format subjectively and objectively in comparison to intermediate views synthesized by MVD format versus total bit-rate.

A Study on the Synthesis of Aluminum Citrate from Aluminum Chloride Solutions (염화(鹽化)알루미늄 수용액(水溶液)으로부터 Aluminum Citrate의 합성(合成) 연구(硏究))

  • Lee, Hwa-Young
    • Resources Recycling
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    • v.18 no.6
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    • pp.18-23
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    • 2009
  • An investigation on the synthesis of aluminum citrate, one of the aluminum organic compounds, has been performed using aluminum chloride solutions as a starting material. For the synthesis of aluminum citrate, citric acid was added to aluminum solutions with the mole ratio of citric acid to aluminum to be 2.5 and aluminum citrate synthesized was also characterized in terms of chemical analysis, X-ray diffraction, particle size measurement and SEM analysis. As a result, it was found that the ratio of ethanol/Al solution more than 4.0 was required for the synthesis of aluminum citrate from aluminum solutions. Furthermore, the pH should be controlled to be more than 7.0 in order to obtain the recovery of aluminum citrate higher than 97%. From the chemical analysis of aluminum citrate synthesized in this work, the content of $NH_4$, Al and C was found to be 17.0, 4.01 and 25.7%, respectively. Accordingly, the aluminum citrate synthesized from aluminum solutions was confirmed to be $(NH_4)_5Al(C_6H_4O_7)_2{\cdot}2H_2O$.