• Title/Summary/Keyword: 초음파화학

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Synthesis and Substituent Effects in Substituted Styryl 4-Methoxy-1-Naphthyl Ketones (다양한 치환기가 붙은 Styryl 4-Methoxy-1-Naphthyl Ketone의 합성과 치환기 효과에 관한 연구)

  • Thirunarayanan, G.;Ananthakrishna Nadar, P.
    • Journal of the Korean Chemical Society
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    • v.50 no.3
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    • pp.183-189
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    • 2006
  • A series of substituted styryl 4-methoxy-1-naphthyl ketones [(2E)-1-(4-methoxy-1-naphthyl)-3-phenyl-2-propen-1-ones] were synthesized using facile method of microwave assisted condensation reaction. The yield of chalcones is more than 90%. They are characterized by their physical constants, micro analysis, infrared (KBr, 4000-400 cm?1) and NMR both 1H and 13C spectral data. From infrared spectra, the s-cis and s-trans stretching vibrations of carbonyl group, from NMR spectra the ethylenic proton and carbon chemical shifts (ppm) are assigned. These spectral data are correlated with various Hammett substituent constants. From the results of statistical analysis the effect of substituents on CO, ? and ? proton and carbons are explained.

Dyeing Properties on Modificated Wool by Micro-split (물리화학적 처리에 의한 마이크로 피브릴화 양모의 염색특성)

  • Choi, Woo-Hyuk;Kim, Mi-Kyung;Jeon, Byung-Dae;Park, Sang-Un
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2011.11a
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    • pp.58-58
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    • 2011
  • 현 의류 섬유산업의 트렌드는 친환경, 무공해, 인체친화, 고감성, 고급스러움 등을 표현할 수 있는 제품으로의 전환이 이루어지고 있으며, 최근 부드럽고, 편안하고, 모던한 특징 및 내추럴한 느낌을 나타내는 천연섬유에 대한 요구가 더욱 늘어나고 있다. 양모 섬유는 천염섬유 중 많은 비중을 차지하고 있는 단백질 섬유로서, 이를 이용한 다양한 직물과 의류제품은 국내외적으로 유명 브랜드 바이어와 지속적으로 내수와 수출이 이루어지는 대표적 섬유이다. 그러나 양모 소재에 특유의 구조와 형태로 소재간 섬도차로 인해 고급섬유에의 복합시 물리적, 감성적 이질감으로 상품화가 제한되고 있으며, 소비자 및 바이어들은 기존 보다 더욱 부드러운 고급감의 양모소재를 선호하고 있다. 이에 천염섬유 중에서도 세섬도 생산의 한계가 있는 양모섬유에 대해 양모섬유의 끝단을 마이크로 분활화 및 세섬화를 가능하게 함으로서 새로운 고감성 및 고급감을 부여할 수 있을 것이며, 본 연구에서는 산 및 초음파 등의 물리화학적 분할 기술을 적용하여 부분적 피브릴화 세섬화된 양모소재에 대한 염가공 특성을 기존 양모소재와 비교 함으로서 개질 양모소재의 제품화 실용성 여부를 검토하였다.

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Development of a High-power Ultrasonic System for Sonochemistry Reaction (음향화학 반응용 강력초음파 개발)

  • Lee, Yang-Lae;Kim, Hyun-Se;Baek, Min-Hyuck
    • Journal of Power System Engineering
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    • v.17 no.6
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    • pp.142-148
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    • 2013
  • High-power ultrasonic promotes a chemical reaction by its own energy, thus it has been used for sonochemistry applications. For example, it has been mostly used for mixing, reaction catalyst, dispersion and disintegration. High-power ultrasonic transducer is made with structure based on a Bolt-clamped Langevin type Transducer (BLT), But it has difficulty in the development because degradation of piezoelectric ceramic by the heat generation of BLT. In this study, for a development of the transducer of 25 kHz and 1000 W used in sonochemistry and industrial cleaning, BLT with a hole in its center and tubular type waveguide of the transducer were designed based on finite element method (FEM). The transducer was fabricated based on the design parameter, and the impedance characteristics are measured experimentally and compared with the numerical results.

Effect of Ultrasound During Pretreatment on the Electrochemical Etching of Aluminum and Its Capacitance (초음파를 이용한 전처리가 알루미늄의 전기화학적 에칭 및 정전용량에 미치는 효과)

  • Jung, Insoo;Tak, Yongsug;Park, Kangyong;Kim, Hyungi;Kim, Sungsoo
    • Corrosion Science and Technology
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    • v.10 no.1
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    • pp.37-42
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    • 2011
  • Aluminum was electrochemically etched in acid solution and the surface area was magnified by the formation of etch pits. Etched aluminum was covered with a compact and dense dielectric oxide film by anodization and applied to the aluminum electrolytic capacitor electrode. Capacitance of aluminum electrolytic capacitor is closely related with surface area, which depends on size and number of etch pits. Size of etch pits need to be controlled because inside of the pits can be buried by the formation of dielectric oxide film. In this work, the effect of ultrasound pretreatment on the aluminum etch pit formation and capacitance were investigated. Additionally, the relationship between the second etching effect on pit size and capacitance was studied.

Extragonadal Intraabdominal Mixed Germ Cell Tumor with Liver Metastasis: Successful Treatment and Long-term Follow-up (간 전이를 동반한 복강 내 성선 외 혼합 생식세포종양: 성공적인 치료 및 장기간 추적관찰)

  • Park, Jinyoung
    • Advances in pediatric surgery
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    • v.19 no.1
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    • pp.25-31
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    • 2013
  • 성선 외 생식세포종양은 비교적 드물어 모든 생식세포종양의 5% 미만을 차지한다. 주로 천미부생식세포종양이 골반부나 후복막으로 확장된 경우가 대부분이며, 후복막이나 복강 내에 발생하는 생식세포종양은 매우 드물다. 저자는 복부 종괴를 주소로 내원한 18개월 된 여아에서 간 전이를 동반한 복강 내 혼합 생식세포종양을 치료하였다. 복부 초음파 및 전산화 단층촬영에서 복부 좌상사분역에 석회화, 고형 및 지방 성분을 포함하고 있는 낭성 종괴와 간에 1cm 크기의 결절이 관찰되었다. 종괴는 개복 후 제거되었으며, 병리조직학적으로 대부분의 내배엽동 종양과 적은 성숙 기형종으로 구성된 혼합 생식세포종양으로 진단되었으며, 간의 전이병변도 동일하게 진단되었다. 수술 후 항암화학요법을 시행하였으며, 환자는 현재 수술 후 10년이 경과하였으나 재발의 소견은 없다.

Maintenance Welding of the Desulfurizer (탈황조의 보수 용접에 관하여)

  • 황근배
    • Journal of Welding and Joining
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    • v.1 no.2
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    • pp.7-11
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    • 1983
  • 본 공장(진해화학주식회사)에서 암모니아는 나프타를 원료로 한 수소와 공기 중의 질소를 합성하여 제조된다. 암모니아 제조 공정 중 메탄가스(CH$_{4}$)와 수소가스(H$_{2}$) 중에 불순물로 존재하는 유화 수소(H$_{2}$S)를 제거시키는 공정이 탈황공정이다. 탈황공정은 산화 아연(ZnO)과 코발트-몰리브덴(Cobalt-Molybdenum) 촉매층에서 이루어지며 탈황공정이 이루어지는 용기를 탈황조(desulfurizer vessel)라 한다. 본 공장에 설치된 탈황조는 1966년에 설치되어 운용되어 왔다. 본 공장의 안전 조업을 위해 초음파 탐상법, 방사선 투과 탐상법, 표면 침투 탐상법으로써 탈황조의 노후도 측정을 행하였다. 탐상 결과 스테인레스 클래드의 모재부 용접선을 따라 균열이 발견되었다. 균열 부위를 깊이 연마하여 용접 결함부를 제거하고 다시 용접을 함으로써 본 탈황조를 연장하여 사용할 수 있었다.

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Chemical Synthesis of Alkyl Polyglucoside Using Ultrasonic Emulsification (초음파유화를 이용한 알킬폴리글루코시드의 화학적 합성)

  • Sunwoo, Hwan;Kim, Hae-Sung
    • Journal of the Korean Applied Science and Technology
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    • v.18 no.2
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    • pp.127-135
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    • 2001
  • Alkyl polyglucosides were synthesized by solvent-free glycosidation using ultrasonic emulsification. We examined glycosidation conditions of fatty alcohol with glucose hydrate and anhydrous glucose in the presence of p-toluenesulfonic acid. Glucose was emulsified in a molar excess of fatty alcohol for 20 minutes with a ultra-sonicator at room temperature and converted in a stirred reactor to more than 95% polyglucoside within $2.5{\sim}3.5$ hr under $20{\sim}30$ mmHg at $110^{\circ}C$ with a three-fold molar ratio of fatty alcohol to glucose in the presence of 1mol% p-toluenesulfonic acid. It was possible to obtain a polyglucoside mixture of HLB 13 consisting of 65% monoglucoside and 35% oligoglucoside with less than 1% of fatty alcohol.

Fabrication of Polymer Thin Films on Solid Substrates (고체 기판에 고분자 박막의 고정화)

  • Kim, Min Sung;Jeong, Yeon Tae
    • Applied Chemistry for Engineering
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    • v.21 no.2
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    • pp.200-204
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    • 2010
  • Surface properties are important for determining the functions and uses of materials. So modification of materials with polymer thin films has emerged as an important method to control the physical and chemical properties of the surface layer. We report a simple and effective method to photochemically attach thin polymeric layers to solid surface without chemical derivatization of the substrate and/or the polymer. The system is based on a photoreactive poly(4-vinylpyridine) (P4VP) thin film which is formed on the $SiO_{2}$ surface via spin coating. This substrate is then covered with another polymer film that is reacted with the benzyl radical moieties by UV irradiation. As a result of photochemical reaction, a thin layer of the later polymer is covalently bound to the surface of P4VP. Unbounded polymer is removed by sonication. The thickness of the attached film is a function of the irradiation time and the molecular weight of the polymer. Spatially defined polymer thin films can be fabricated by way of photolithography.

A Study on the Relationship between Carotid Artery Intima-Media Thickness and Clinical Chemistry Tests (경동맥 초음파 결과와 임상화학 검사의 상관성 연구)

  • Kim, Dae-Sik;Sung, Hyun-Ho;Cho, Eun-kyung;Lee, Jong-Woo
    • Korean Journal of Clinical Laboratory Science
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    • v.47 no.4
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    • pp.188-193
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    • 2015
  • Carotid Intima-Media Thickness (CIMT) testing is a test that precisely assesses cerebrovascular and coronary heart diseases. According to many previous studies, CIMT predicts atherosclerosis and is highly correlated to cardiovascular disease risk factors. It has also been reported that CIMT is an independent predictor of risk factors for myocardial infarction and stroke. Therefore, the purpose of this study is to investigate CIMT and other independent factors through a correlation study with the clinical laboratory test results of a blood test. As a result, this study could not prove the correlation between CIMT and risk factors of cardiovascular disease (TC, TG, LDL cholesterol, and HDL cholesterol) due to an insufficient number of subjects. Nevertheless, a positive correlation was demonstrated between CIMT and ALT (p<0.05), GGT (p<0.05), Uric acid (p<0.05), and CEA (p<0.05) at a statistically significant level, suggesting a continuation of the study.

Electrochemical Characteristics of the Oxygen Electrode for Alkaline Fuel Cells -Impregnation of Silver Catalyst on Carbon Black with Colloidal Method- (알칼리형 연료전지용 산소극의 전기화학적 특성고찰 -콜로이드 방법에 의한 카본블랙상 은촉매담지-)

  • Lee, Hong-Ki;Lee, Ju-Seong
    • Applied Chemistry for Engineering
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    • v.3 no.4
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    • pp.701-709
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    • 1992
  • Silver particles were impregnated on carbon black with colloidal method and used as catalyst for oxygen electrode in alkaline fuel cell. With the addition of sodium dodecylbenzenesulfonate in $AgNO_3$ and $NaBH_4$solution, colloidal solution was made and confirmed with electrophoresis test. Effects of particle size on electrode performance were studied and $200{\AA}$ of silver particle size shown the highest value of mass activity. The aggromeration of silver particle was Influenced with surfactant amount, stirring time and heat treatment. Considering the increase of particle size caused of operating temperature, recommendable particle size of silver catalyst for manufacturing the electrode was $100{\AA}$. Dispersity of carbon black was investigated and reagglomeration was appeared after homogenizing 30 sec.

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