• 제목/요약/키워드: IR-UV

검색결과 1,090건 처리시간 0.023초

구굴무치과에 속하는 동사리와 얼룩동사리의 Carotenoid 색소성분의 비교 (Comparison of Carotenoid Pigments on Korean Dark Sleeper, Odontobutis platycephala and Dark Sleeper, Odontobutis odontobutis interrupta in the Family Eleotridae)

  • 하봉석;김명선;백승한;김현영;김수영;정계임;권문정
    • 한국식품영양과학회지
    • /
    • 제27권5호
    • /
    • pp.813-820
    • /
    • 1998
  • This study was performed as a part of comparative biochemical studies of carotenoid pigment for the fresh water fish. Carotenoids in integument of Korean dark sleeper, Odontobutis platycephala, and dark sleeper, Odontobutis odontobutis interrupta, which are all the Korean native fresh water fish, were separated by thin layer chromatography, column chromatography and HPLC. The separated carotenoid were then reduced and isomerized by NaBH4 and I2 respectively to investigate UV-Vis spectrophotometeric patterns and chracterized by IR, 1H-NMR and Mass spectrum. The content of total carotenoids in the integument of Korean dark sleeper was 3.01mg% in April, but it was increased to 3.74mg% in September at the near of spawning period. The carotenoid isolated in April consisted of $\beta$-carotene(25.6%), lutein(18.5%) and zeaxanthin(12.0%) as major carotenoids and also contained isocryptoxanthin, diatoxanthin, tunaxanthin, cynthiaxanthin, canthaxanthin and $\alpha$-cryptoxanthin as minor carotenoids. Similarly, in September the carotenoid consisted of $\beta$-carotene(16.5%), zeaxanthin(13.7%) and cynthiaxanthin(13.6%) as major carotenoids and also contained lutein, isocryptoxanthin, tunaxanthin, $\alpha$-cryptoxanthin, diatoxanthin and canthaxanthin as minor carotenoids. At the near of spawning period, the content of cynthiaxanthin and $\alpha$-cryptoxanthin were increased. The content of total carotenoids in the integument of spawning period. T도 carotenoid isolated in April and September consisted of $\beta$-carotene(24.9%, 27.5%), zeaxanthin(14.4%, 20.9%) and lutein(12.6%, 11.4%) as major carotenoids and also contained cynthiaxanthin, tunaxanthin, diatoxanthin, isocryptoxanthin, $\alpha$-cryp-toxanthin and canthaxanthin as minor carotenoids. At the near of spawning period, the content of zeaxanthin was increased, indicating that the carotenoid composition were dependent upon their living conditions and their integument colors. Both Korean dark sleeper and dark sleeper contained high amount of cynthiaxanthin and diatoxanthin which are found as rare carotenoids in the other of fresh water fish. It is interes that they also contained tunaxanthin which is a specific carotenoid in marine fishes.

  • PDF

다섯자리 Schiff Base Molybdenum(Ⅴ) 착물들의 합성과 비수용매에서의 전기화학적 성질 (Synthesis of Pentadentate Schiff Base Molybdenum(Ⅴ) Complexes and Their Electrochemical Properties in Aprotic Solvents)

  • 김선숙;최주형;최용국;정병구
    • 대한화학회지
    • /
    • 제38권2호
    • /
    • pp.160-168
    • /
    • 1994
  • 다섯자리 Schiff base의 molybdenum(Ⅴ)착물로써 [Mo(Ⅴ)O(Sal-DET)(NCS)] 와 [Mo(Ⅴ)O(Sal-DPT)(NCS)]들을 Sabat법에 의해 합성하였다. 이들 착물들의 원소분석, IR-spectrum, UV-Vis spectroscopy 및 Thermogravimetric analysis(T.G.A.)곡선으로부터 리간드 대 금속의 몰비가 1:1착물임을 확인하였다. 0.1M tetraethyl ammonium perchlorate(TEAP)지지전해질을 포함한 비수용매에서 순환 전압-전류법과 시차펄스 폴라그래피에 의한 전기화학적 측정으로부터 이들 착물들은 dimer로 형성된 후, 일전자 전이의 확전자 전이의 확산지배적인 환원과정이 다음과 같이 네단계로 진행됨을 알았다. 2Mo(Ⅴ)$\rightleftarrow^{e-}$ Mo(Ⅴ)Mo(Ⅳ) $\longrightarrow^{e-}$ 2Mo(Ⅳ), Mo(Ⅳ)$\longrightarrow^{e-}$ Mo(Ⅲ) $\longrightarrow^{e-}$ Mo(Ⅱ)

  • PDF

Transition Metal Complexes Derived From 2-hydroxy-4-(p-tolyldiazenyl)benzylidene)-2-(p-tolylamino)acetohydrazide Synthesis, Structural Characterization, and Biological Activities

  • Alhakimi, Ahmed N.;Shakdofa, Mohamad M.E.;Saeed, S. El-Sayed;Shakdofa, Adel M.E.;Al-Fakeh, Maged S.;Abdu, Ashwaq M.;Alhagri, Ibrahim A.
    • 대한화학회지
    • /
    • 제65권2호
    • /
    • pp.93-105
    • /
    • 2021
  • Mononuclear Cu(II), Ni(II), Co(II), Mn(II), Zn(II), Fe(III), Ru(III), and UO2(II) complexes of 2-hydroxy-4-(p-tolyldiazenyl)benzylidene)-2-(p-tolylamino)acetohydrazide (H2L) were prepared by direct method. The ligand and its complexes were isolated in solid state and characterized by analytical techniques such as elemental and thermal analyses, molar conductance, magnetic susceptibility measurements and spectroscopic techniques such as UV-Visible, IR, 1H-NMR and 13C-NMR. The spectral data indicated that the ligand acted as neutral/monobasic bidentate or monobasic/dibasic tridentate ligand bonded to the metal ions through the oxygen atom of ketonic or enolic carbonyl group, azomethine nitrogen atom and deprotonated/protonated phenolic oxygen atom forming either tetragonally distorted octahedral or octahedral. Antimicrobial activities of the ligand and its complexes were evaluated against Escherichia coli, Bacillus subtilis and Aspergillus niger by well diffusion method. The results of antifungal activity showed that the Fe(III) complex (10) exhibited higher antifungal against Aspergillus niger than the other complexes. However, the results of antibacterial activity revealed that Cu(II) complex (4) is the most active against Escherichia coli while the Cu(II) complex (5) and Fe(III) complex (10) exhibited higher antibacterial effect on Bacillus subtilis than the other complexes.

PRAM용 Cu-도핑된 Ge8Sb2Te11 박막의 특성 (Characteristics of Cu-Doped Ge8Sb2Te11 Thin Films for PRAM)

  • 김영미;공헌;김병철;이현용
    • 한국전기전자재료학회논문지
    • /
    • 제32권5호
    • /
    • pp.376-381
    • /
    • 2019
  • In this work, we evaluated the structural, electrical and optical properties of $Ge_8Sb_2Te_{11}$ and Cu-doped $Ge_8Sb_2Te_{11}$ thin films prepared by rf-magnetron reactive sputtering. The 200-nm-thick deposited films were annealed in a range of $100{\sim}400^{\circ}C$ using a furnace in an $N_2$ atmosphere. The amorphous-to-crystalline phase changes of the thin films were investigated by X-ray diffraction (XRD), UV-Vis-IR spectrophotometry, a 4-point probe, and a source meter. A one-step phase transformation from amorphous to face-centered-cubic (fcc) and an increase of the crystallization temperature ($T_c$) was observed in the Cu-doped film, which indicates an enhanced thermal stability in the amorphous state. The difference in the optical energy band gap ($E_{op}$) between the amorphous and crystalline phases was relatively large, approximately 0.38~0.41 eV, which is beneficial for reducing the noise in the memory devices. The sheet resistance($R_s$) of the amorphous phase in the Cu-doped film was about 1.5 orders larger than that in undoped film. A large $R_s$ in the amorphous phase will reduce the programming current in the memory device. An increase of threshold voltage ($V_{th}$) was seen in the Cu-doped film, which implied a high thermal efficiency. This suggests that the Cu-doped $Ge_8Sb_2Te_{11}$ thin film is a good candidate for PRAM.

Dioxygen Binding to Dirhodium(Ⅱ, Ⅱ), (Ⅱ, Ⅲ), and (Ⅲ, Ⅲ) Complexes. Spectroscopic Characterization of $[Rh_{2}(ap)_{4}(O_{2})]^{+},\;Rh_{2}(ap)_{4}(O_{2}),\;and\;[Rh_{2}(ap)_{4}(O_{2})]^-$, where ap=2-anilinopyridinate Ion

  • Lee, Jae-Duck;Yao, Chao-Liang;Capdevielle, Francoise J.;Han, Bao-Cheng;Bear, John L.;Kadish, Karl M.
    • Bulletin of the Korean Chemical Society
    • /
    • 제14권2호
    • /
    • pp.195-200
    • /
    • 1993
  • The neutral, reduced, and oxidized 2,2-trans isomers of $Rh_2(ap)_4$ (ap=2-anilinopyridinate) were investigated with respect to dioxygen binding in $CH_2Cl_2$ containing 0.1 M tetrabutyl-ammonium perchlorate. $Rh_2(ap)_4$ binds dioxygen in nonaqueous media and forms a $Rh^{II}Rh^{III}$ superoxide complex, $Rh_2(ap)_4(O_2)$. This neutral species was isolated and is characterized by UV-visible and IR spectroscopy, mass spectrometry and cyclic voltammetry. It can be reduced by one electron at $E_{1/2}$ = -0.45 V vs. SCE in $CH_2Cl_2$ and gives ${[Rh_2(ap)_4(O_2)]}^-$ as demonstrated by the ESR spectrum of a frozen solution taken after controlled potential reduction. The superoxide ion in ${[Rh_2(ap)_4(O_2)]}^-$ is axially bound to one of the two rhodium ions, both of which are in a +2 oxidation state. $Rh_2(ap)_4(O_2)$ can also be stepwise oxidized in two one-electron transfer steps at $E_{1/2}$ = 0.21 V and 0.85 V vs. SCE in $CH_2Cl_2$ and gives ${[Rh_2(ap)_4(O_2)]}^+$ followed by ${[Rh_2(ap)_4(O_2)]}^{2+}$. ESR spectra demonstrate that the singly oxidized complex is best described as ${[Rh^{II}Rh^{III}(ap)_4(O_2)]}^+$ where the odd electron is delocalized on both of the two rhodium ions and the axial ligand is molecular oxygen.

Effect of method of synthesis on antifungal ability of ZnO nanoparticles: Chemical route vs green route

  • Patino-Portela, Melissa C.;Arciniegas-Grijalba, Paola A.;Mosquera-Sanchez, Lyda P.;Sierra, Beatriz E. Guerra;Munoz-Florez, Jaime E.;Erazo-Castillo, Luis A.;Rodriguez-Paez, Jorge E.
    • Advances in nano research
    • /
    • 제10권2호
    • /
    • pp.191-210
    • /
    • 2021
  • To compare the antifungal effect of two nanomaterials (NMs), nanoparticles of zinc oxide were synthesized by a chemical route and zinc oxide-based nanobiohybrids were obtained using green synthesis in an extract of garlic (Allium sativum). The techniques of X-Ray Diffraction (XRD), Infrared (IR) and Ultraviolet Visible (UV-Vis) absorption spectroscopies and Scanning (SEM) and Transmission Electron Microscopies (TEM) were used to determine the characteristics of the nanomaterials synthesized. The results showed that the samples obtained were of nanometric size (< 100 nm). To compare their antifungal capacity, their effect on Cercospora sp. was evaluated. Test results showed that both nanomaterials had an antifungal capacity. The nanobiohybrids (green route) gave an inhibition of fungal growth of ~72.4% while with the ZnO-NPs (chemical route), inhibition was ~87.1%. Microstructural studies using High Resolution Optical Microscopy (HROM) and ultra-structural analysis using TEM carried out on the treated strains demonstrated the effect of the nanofungicides on the vegetative and reproductive structures, as well as on their cell wall. To account for the antifungal effect presented by ZnO-NPs and ZnO nanobiohybrids on the fungi tested, effects reported in the literature related to the action of nanomaterials on biological entities were considered. Specifically, we discuss the electrical interaction of the ZnO-NPs with the cell membrane and the biomolecules (proteins) present in the fungi, taking into account the n-type nature of the ZnO semiconductor and the electrical behavior of the fungal cell membrane and that of the proteins that make up the protein crown.

Neuroprotective Compounds Isolated from Lysimachia christinae

  • Gahee Ryu;Choong Je Ma
    • Natural Product Sciences
    • /
    • 제29권1호
    • /
    • pp.10-16
    • /
    • 2023
  • We previously reported that dried Lysimachia christinae whole plant extract exerted significant neuroprotective activity. In this study, we tried to isolate neuroprotective compounds of L. christinae. We evaluated the neuroprotective activity of the four fractions (hexane, chloroform, ethyl acetate, and n-butanol fractions) of methanol extract. Among them, ethyl acetate and n-butanol fractions showed most potent neuroprotective activity against glutamate excitotoxicity. Nine compounds were isolated from ethyl acetate and n-butanol fractions of L. christinae extract and identified as cynaroside (1), (3,4,5,6-tetrahydroxytetrahydro-2H-pyran-2-yl)methyl-3-hydroxy-2-octyldopentaconta-23,33-dienoate (2), androst-16-ene-3,6-diol (3), 2-hydroxy-24-propoxytetracos-4-enoic acid (4), 2-hydroxy-24-methoxytetracos-4-enoic acid (5), 12-(stearoyloxy)octadec-9-enoic acid (6), β-sitosterol (7), (E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl palmitate (8) and (1S,2S,3R,4R)-4-(((2S,3R,4R,5R,6S)-2-(((2R,3R,4S,5R,6R)-2-(3,4-dimethoxyphenethoxy)-3,5-dihydroxy-6-(hydroxymethyl) tetrahydro-2H-pyran-4-yl)oxy)-4,5-dihydroxy-6-methyltetrahydro-2H-pyran-3-yl)oxy)cyclohexane-1,2,3-triol (9) by spectroscopic data such as UV, IR, NMR, Mass spectroscopy. Their neuroprotective activity was evaluated by MTT assay. Cynaroside (1) and androst-16-ene-3,6-diol (3) had significant neuroprotective activity against glutamate-injured HT22 cells. The neuroprotective efficacy of cynaroside (1) and androst-16-ene-3,6-diol (3) was related to their anti-oxidative activity.

용액 플라즈마를 이용한 콜로이드 및 나노 구조 MnO2의 친환경 합성 (Green Synthesis of Colloidal and Nanostructured MnO2 by Solution Plasma Process)

  • 김혜민
    • 한국재료학회지
    • /
    • 제33권7호
    • /
    • pp.315-322
    • /
    • 2023
  • In the present work, we address the new route for the green synthesis of manganese dioxide (MnO2) by an innovative method named the solution plasma process (SPP). The reaction mechanism of both colloidal and nanostructured MnO2 was investigated. Firstly, colloidal MnO2 was synthesized by plasma discharging in KMnO4 aqueous solution without any additives such as reducing agents, acids, or base chemicals. As a function of the discharge time, the purple color solution of MnO4- (oxidation state +7) was changed to the brown color of MnO2 (oxidation state +4) and then light yellow of Mn2+ (oxidation state +2). Based on the UV-vis analysis we found the optimal discharging time for the synthesis of stable colloidal MnO2 and also reaction mechanism was verified by optical emission spectroscopy (OES) analysis. Secondly, MnO2 nanoparticles were synthesized by SPP with a small amount of reducing sugar. The precipitation of brown color was observed after 8 min of plasma discharge and then completely separated into colorless solution and precipitation. It was confirmed layered type of nanoporous birnessite-MnO2 by X-ray powder diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), and electron microscopes. The most important merits of this approach are environmentally friendly process within a short time compared to the conventional method. Moreover, the morphology and the microstructure could be controllable by discharge conditions for the appropriate potential applications, such as secondary batteries, supercapacitors, adsorbents, and catalysts.

무기산 누출 사고 대응을 위한 탐지·분석 방법 연구 (Study on the Methods of Detection and Analysis for Responding Inorganic Acids Spill)

  • 이진선;정미숙;김기준;안성용;윤영삼;윤준헌
    • 한국위험물학회지
    • /
    • 제2권1호
    • /
    • pp.6-11
    • /
    • 2014
  • There have been frequent chemical leaks over the past 10 years. Particularly, inorganic acids like sulfuric acid, nitric acid, and hydrogen chloride take up 37 % of the total chemical accidents which took place for the past 10 years. When an acid chemical leak happens, fume is generated, diffusing into the air, which might cause serious damage to health of local residents and the environment. However, most of the acid-based chemicals, detecting and analysis methods have not been settled considering the frequency of accidents. In this study, we investigated detection and analysis methods to quickly analyze accident sites and evaluate the impacts on environments. Reviewing local and international test analysis methods of acids suggested that nitric acid, sulfuric acid, hydrogen chloride and hydrogen fluoride can be analyzed with IC. It was also found that UV is better for the analysis of hydrogen fluoride and GC/MS for acrylic acid. The analytical methods suggested in the official test methods basically have limitations of consuming much time at stages of preparation and analysis. Considering prompt responses to chemical accidents, further studies should be done to compare the applicability of rapid monitoring methods such as FT-IR, IMR-MS and SIFT-MS.

폐기되는 표고버섯 핀 추출물을 이용한 혼합염색 효과 - 염색성과 기능성을 중심으로 - (Effect of Mixed Dyeing Using Discarded Shiitake Mushroom Pin Extract - Focused on Dyeability and Functionality -)

  • 손경희
    • 한국의류산업학회지
    • /
    • 제26권4호
    • /
    • pp.411-423
    • /
    • 2024
  • This study examined the dyeability and functionality of silk fabrics dyed using shiitake mushroom pins discarded in large quantities on mushroom farms. FT-IR and UV-Vis spectral analyses showed that polyphenols and flavonoids were present in the hot-water extract of shiitake mushroom pins. Optimal dyeing conditions for silk fabrics were a dye concentration of 50% (v/v), dyeing temperature of 80℃, dyeing time of 60 minutes, and dyebath pH of 5.3. The post-mordant method showed a greater effect on the increase in dye uptake and color change than the pre-mordant method. Unmordanted fabrics appeared as a YR Munsell color. Except for the Cu-mordant, all post-mordanted fabrics produced a Y Munsell color. The FE-SEM/EDX analysis confirmed that the natural iron solution and mud contained various metal ions. The Fe component was found to have the greatest effect on the dye uptake and color properties. The colorfastness of the unmordanted fabrics to washing, dry cleaning, rubbing, and perspiration was excellent (above grade 4), whereas light was grade 3-4. In the case of post-mordanted fabrics with a natural iron solution, the colorfastness to washing, wet rubbing, and light improved by 0.5 grades. For post-mordanted fabrics with mud, the colorfastness to light and sweat improved by 0.5 grades. The bacterial reduction rate for staphylococcus aureus in fabrics dyed with shiitake mushroom pin extract was excellent at over 99.9%, the bacterial reduction rate for klebsiella pneumoniae was 98.1%, and the deodorization rate was excellent at 90%. These results indicate that shiitake mushroom pins can be used as a sustainable, functional natural dye.