• 제목/요약/키워드: conjugate addition

검색결과 140건 처리시간 0.025초

Reaction of Lithium 2-Pyridyloxyalkylcuprates Having Improved Thermal Stability with Acid Chlorides and $\alpha,\beta$-Unsaturated Ketones

  • Lee, Phil-Ho;Shim, Sang-Chul;Kim, Sung-Gak
    • Bulletin of the Korean Chemical Society
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    • 제7권6호
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    • pp.425-428
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    • 1986
  • A new heterocuprate containing 2-pyridyloxy ligand, lithium 2-pyridyloxy-n-butylcuprate, has shown improved thermal stability and it reacts with acid chlorides to afford the corresponding ketones in high yields. Similarly, it can be effectively utilized in conjugate addition reactions of $\alpha,\beta$-unsaturated ketones. Of synthetic significance is that the complete utilization of n-butyl group in lithium 2-pyridyloxy-n-butylcuprate has been observed.

적외선 표적 모델링을 위한 3차원 복합 열해석 기법 연구 (Three-Dimensional Conjugate Heat Transfer Analysis for Infrared Target Modeling)

  • 장현성;하남구;이승하;최태규;김민아
    • 정보과학회 논문지
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    • 제44권4호
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    • pp.411-416
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    • 2017
  • 적외선 표적의 정밀한 모델링을 위해서는 정확한 표면온도 계산이 필요하다. 본 논문에서는 전도, 대류, 복사를 고려한 복합 열해석 모듈을 소프트웨어로 구현하고, 이를 통하여 표적 재질 및 자세, 환경 요건에 따른 표적의 표면온도 해석을 수행 하였다. 구현된 결과는 상용 소프트웨어인 OKTAL-SE 와의 비교를 통하여 결과의 신뢰성을 검증하였다. 그 결과 자체 검증이 완료된 상용 소프트웨어인 OKTAL-SE 와 약 1% 이내의 오차를 보였다. 계산된 온도 결과를 바탕으로 적외선 표적 모델링을 수행하였으며 OKTAL-SE와의 연동을 통해 적외선 신호 해석을 수행하였다.

Cost optimization of reinforced high strength concrete T-sections in flexure

  • Tiliouine, B.;Fedghouche, F.
    • Structural Engineering and Mechanics
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    • 제49권1호
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    • pp.65-80
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    • 2014
  • This paper reports on the development of a minimum cost design model and its application for obtaining economic designs for reinforced High Strength Concrete (HSC) T-sections in bending under ultimate limit state conditions. Cost objective functions, behavior constraint including material nonlinearities of steel and HSC, conditions on strain compatibility in steel and concrete and geometric design variable constraints are derived and implemented within the Conjugate Gradient optimization algorithm. Particular attention is paid to problem formulation, solution behavior and economic considerations. A typical example problem is considered to illustrate the applicability of the minimum cost design model and solution methodology. Results are confronted to design solutions derived from conventional design office methods to evaluate the performance of the cost model and its sensitivity to a wide range of unit cost ratios of construction materials and various classes of HSC described in Eurocode2. It is shown, among others that optimal solutions achieved using the present approach can lead to substantial savings in the amount of construction materials to be used. In addition, the proposed approach is practically simple, reliable and computationally effective compared to standard design procedures used in current engineering practice.

A Quinoline-thiooxorhodamine Conjugate for Fluorescent Hg2+ Recognition in Aqueous Media and Living Cells

  • Tang, Lijun;Wen, Xin;Dai, Xin;Wu, Di;Huang, Zhenlong
    • Bulletin of the Korean Chemical Society
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    • 제35권11호
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    • pp.3326-3330
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    • 2014
  • A quinoline-thiooxorhodamine conjugate fluorescent sensor (1) has been synthesized. Sensor 1 exhibits high selectivity and sensitivity to $Hg^{2+}$ in $H_2O$/DMSO (95/5, v/v, HEPES 20 mM, pH = 7.4) solution with fluorescence detection. Other tested metal ions do not induce any significant fluorescence intensity changes. Sensor 1 interacts with $Hg^{2+}$ through a 1:1 binding stoichiometry with a good anti-inference ability. In addition, fluorescent imaging of $Hg^{2+}$ in Hela cells is also successfully demonstrated.

REGISTRATION OF IKONOS-2 GEO-LEVEL SATELLITE IMAGERY USING ALS DATA;BY USING LINEAR FEATURES AS REGISTRATION PRIMITIVES

  • Lee, Jae-Bin;Song, Woo-Seok;Lee, Chang-No;Yu, Ki-Yun;Kim, Yong-Il
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.14-17
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    • 2007
  • To make use of surveying data obtained from different sensors and different techniques in a common reference frame, it is a pre-requite step to register them in a common coordinate system. For this purpose, we have developed a methodology to register IKONOS-2 Satellite Imagery using ALS data. To achieve this, conjugate features from these data should be extracted in advance. In the study, linear features are chosen as conjugate features because they can be accurately extracted from man-made structures in urban area, and more easily than point features from ALS data. Then, observation equations are established from similarity measurements of the extracted features. During the process, considering the characteristics of systematic errors in IKONOS-2 satellite imagery, the transformation function were selected and used. In addition, we also analyzed how the number of linear features and their spatial distribution used as control features affect the accuracy of registration. Finally, the results were evaluated statistically and the results clearly demonstrated that the proposed algorithms are appropriate to register these data.

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Hepatotoxic Effect of 1-Bromopropane and Its Conjugation with Glutathione in Male ICR Mice

  • Lee Sang Kyu;Jo Sang Wook;Jeon Tae Won;Jun In Hye;Jin Chun Hua;Kim Ghee Hwan;Lee Dong Ju;Kim Tae-Oh;Lee Eung-Seok;Jeong Tae Cheon
    • Archives of Pharmacal Research
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    • 제28권10호
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    • pp.1177-1182
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    • 2005
  • The hepatotoxic effects of 1-bromopropane (1-BP) and its conjugation with glutathione were investigated in male ICR mice. A single dose (1000 mg/kg, po) of 1-BP in corn oil to mice significantly increased serum activities of alanine aminotransferase and aspartate aminotransferase. Glutathione (GSH) content was dose-dependently reduced in liver homogenates 12 h after 1-BP treatment. In addition, 1-BP treatment dose-dependently increased levels of S-pro-pyl GSH conjugate at 12 h after treatment, as measured by liquid chromatography-electro-spray ionization tandem mass spectrometry. The GSH conjugate was maximally increased in liver at 6 h after 1-BP treatment (1000 mg/kg), with a parallel depletion of hepatic GSH content. Finally, 1-BP induced the production of malondialdehyde in liver. The present results suggest that 1-BP might cause hepatotoxicity, including lipid peroxidation via the depletion of GSH, due to the formation of GSH conjugates in male ICR mice.

Partitioning effects and corrosion characteristics of oxyapatite glass-ceramic wasteforms sequestering rare-earth elements

  • Kim, Miae;Kang, Jaehyuk;Yoon, Jang-Hee;Lee, Sang-Geul;Um, Wooyong;Kim, Hyun Gyu
    • Nuclear Engineering and Technology
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    • 제54권3호
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    • pp.997-1002
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    • 2022
  • Oxyapatite[Ca2Nd8(SiO4)6O2] glass-ceramics have been suggested as wasteforms for the immobilisation of rare-earth radioactive nuclides because of their high waste-loading capability and good chemical durability. In particular, a partitioning effect is predicted to contribute to an enhancement of corrosion resistance in glass-ceramics compared with that of conjugate glasses of the same composition. Because rare-earths are inherently insoluble nuclides, detection of changes in corrosion behavior between glass-ceramics and conjugate glasses under normal conditions is not easy. In this study, therefore, we revealed the partitioning effect by exposing glass-ceramics and glasses to solution of pH 2, 7 and 10 at 90 ℃ for 20 d. In addition, we proposed the corrosion mechanism for oxyapatite glass-ceramics under various corrosion conditions. Especially, the glassy phase dissolved first, followed by the oxyapatite phase during pH 7 corrosion.

Recommended immunization schedule for children and adolescents: Immunization Guideline (8th edition) released by the Korean Pediatric Society in 2015

  • Kim, Jong-Hyun;Choi, Eun Hwa;Park, Su Eun;Kim, Yae-Jean;Jo, Dae Sun;Kim, Yun-Kyung;Eun, ByungWook;Lee, Jina;Lee, Soo-Young;Lee, Hyunju;Kim, Ki Hwan;Kim, Kyung-Hyo
    • Clinical and Experimental Pediatrics
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    • 제59권12호
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    • pp.461-465
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    • 2016
  • This report includes the recommended immunization schedule table for children and adolescents based on the 8th (2015) and revised 7th (2012) Immunization Guidelines released by the Committee on Infectious Diseases of the Korean Pediatric Society (KPS). Notable revised recommendations include: reorganization of the immunization table with a list of vaccines on the vertical axis and the corresponding age on the horizontal axis; reflecting the inclusion of Haemophilus influenzae type b vaccine, pneumococcal conjugate vaccine, and hepatitis A vaccine into the National Immunization Program since 2012; addition of general recommendations for 2 new Japanese encephalitis (JE) vaccines and their interchangeability with existing JE vaccines; addition of general recommendations for quadrivalent meningococcal conjugate vaccines and scope of the recommended targets for vaccination; and emphasizing catch-up immunization of Tdap vaccine. Detailed recommendations for each vaccine may be obtained from the full KPS 8th Immunization Guidelines.

Streptomycin-anionic linear globular dendrimer G2: Novel antibacterial and anticancer agent

  • Javadi, Sahar;Ardestani, Mehdi Shafiee
    • Advances in nano research
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    • 제7권4호
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    • pp.241-248
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    • 2019
  • Recent researches demonstrated well promising anticancer activities for antibiotics. Such effects would be significantly increased while nanoparticle based delivery systems were applied. In this study, the goal was aim to improve anticancer and antitoxic effects of Streptomycin by loading on special kind of dendrimer (anionic-linear-globular second generation). In the current study, Size and zeta potential as well as AFM techniques have been used to prove the fact that the loading was performed correctly. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the drug loaded on dendrimer nanoparticle were determined and compared with both of dendrimer alone and free drug with respect to staphylococcus aureus as the test microorganism. The anticancer activity among three groups including Streptomycin, Streptomycin -G2 dendrimer, and control was measured in vitro. In vitro studies showed that G2 anionic linear-globular polyethylene-glycol-based dendrimer, which loaded on Streptomycin was able to significantly improve the treatment efficacy over clinical Streptomycin alone with respect to proliferation assay. Maximal inhibitory concentration (IC50) was calculated to be $257{\mu}g/mL$ for streptomycin alone and $55{\mu}g/mL$ for Streptomycin -G2 dendrimer. In addition, Streptomycin -G2 dendrimer conjugate prevented the growth of MCF-7 cancerous cells in addition to enhance the number of apoptotic and necrotic cells as demonstrated by an annexin V-fluorescein isothiocyanate assay. Streptomycin -G2 dendrimer conjugate was able to increase Bcl-2/Bax ratio in a large scale compared with the control group and Streptomycin alone. Based on results a new drug formulation based nano-particulate was improved against S. aureus with sustained release and enhanced antibacterial activity as well as anticancer activity shown for functional cancer treatment with low side effects.