• Structural Engineering and Mechanics
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• v.76 no.6
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• pp.709-724
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• 2020

The typical inerter system, the tuned viscous mass damper (TVMD), has been proven to be efficient. It is characterized by an energy-dissipation-enhancement effect, whereby the dashpot deformation of TVMD can be amplified for enhanced energy dissipation efficiency. However, existing studies related to TVMD have mainly been performed on elastic structures, so the working mechanism remains unclear for nonlinear structures. To deal with this, an energy-spectrum analysis framework is developed systematically for classic bilinear hysteretic structures with TVMD. Considering the soil effect, typical bedrock records are propagated through the soil deposit, for which the designed input energy spectra are proposed by considering the TVMD parameters and structural nonlinear properties. Furthermore, the energy-dissipation-enhancement effect of TVMD is quantitatively evaluated for bilinear hysteretic structures. The results show that the established designed input energy spectra can be employed to evaluate the total energy-dissipation burden for a nonlinear TVMD structure. Particularly, the stiffness of TVMD is the dominant factor in adjusting the total input energy. Compared with the case of elastic structures, the energy-dissipation-enhancement effect of TVMD for nonlinear structures is weakened so that the expected energy-dissipation effect of TVMD is replaced by the accumulated energy dissipation of the primary structure.

• Bulletin of the Korean Chemical Society
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• v.24 no.4
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• pp.473-478
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• 2003

3-Amino-2-hydroxy-4(3H)-quinazolinone (3) was prepared via condensation of 1 with hydrazine hydrate. Treatment of 3 with appropriate acid in $POCl_3$, ethyl chloroacetate and activated olefinic compounds in DMF yielded the corresponding 3-(substituted)amino-2-hydroxy-4(3H)-quinazolinones 4, 5 and 6. The electron impact ionization mass spectra of compounds 3 and 4 show a weak molecular ion peak and a base peak of m/z 146 resulting from a cleavage fragmentation. The compounds 5 and 6 give a characteristic fragmentation pattern with a very stable fragment of benzopyrazolone (m/z 132).

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.987-992
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• 2012

Magnetic nanoparticles (MNPs) treated with phosphoric acid were used to improve sequence coverage in protein identification by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). Sample solution of tryptic peptides from proteins was mixed with the MNPs, and the MNPs were separated from the supernatant using a magnet. MALDI mass spectra obtained separately from the supernatant and the MNPs were distinctly different and complementary to each other. Combination of the two spectra led to a significantly increased sequence coverage.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.51.2-51.2
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• 2012

Red Active Galactic Nuclei (AGNs) are suspected to intermediate stage between ULIRG and AGN phase. As well as, red AGNs are suspected to have more than 50% of whole AGN population. For understanding the characteristics of red AGN, Black Hole (BH) mass is a key property and can not be estimated by existed method such as reverberation mapping and single epoch method using 5100A continuum and Balmer lines. Thus we still don't know their characteristics and properties in clearly. To estimate properties of red AGNs without the effect of dust extinction, we obtained Near InfraRed (NIR) spectra of 31 reverberation mapped AGNs and 49 Palomar-Green(PG) Quasi-Stellar Objects (QSOs) by using the infrared camera (IRC) of AKARI space telescope with unique wavelength range 2.5-5.0 ${\mu}m$. Upon this spectra, we measured the FWHM and luminosity of Brackett ${\alpha}$ and ${\beta}$ lines for deriving new BH mass estimators of AGNs.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.2
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• pp.32.2-32.2
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• 2010

Red dusty Active Galactic Nuclei (AGNs) are suspected to mid-stage between ULIRG and AGN phase. As well as, they are suspected that they have more than 50% of AGN population. To understand character of red AGN, Black Hole (BH) mass of red AGN is a key property and haven't measured by existing method such as reverberation mapping and single epoch method. So we still don't know their character and properties clearly. To estimate properties of red AGNs escape from effect of dust-obscuration, we have obtained Near InfraRed (NIR) spectra of 31 reverberation mapped AGNs and 49 Palomar-Green(PG) Quasi-Stellar Object (QSO) using the infrared camera (IRC) for AKARI with unique wavelength range 2.5-$5.0{\mu}m$. From this spectra, we measured the FWHM and luminosity of brackett ${\alpha}$, ${\beta}$ at 4.0, 2.6 micron meter for deriving new BH mass estimators based on the properties of Brackett line emission.

• Analytical Science and Technology
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• v.8 no.4
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• pp.715-722
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• 1995

The structural characterization for series of polyesters has been done by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Polymer fragments and intact oligomers composed of large numbers of repeat units have been investigated. Transesterification of polyesters in trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CFA) was monitored and reaction products were identified using TOF-SIMS. The shapes and intensities of clusters in transesterification spectra show good agreement with the theoretical isotope pattern. TOF-SIMS spectra were used to obtain information about the progress of the transesterification reaction.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2665-2668
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• 2009

A new algorithm for determining noise level is proposed for more reliability in interpreting spectral data for complex Fourier transform ion cyclotron resonance (FTICR) mass spectra of petroleum. In the new algorithm, a moving window with a fixed number of data points was adopted, instead of a fixed m/z width. In the analysis of petroleum, it was found that a moving window of 50,000 or more data points was optimal. This optimized automated peak picking performed well even with frequency-dependant noise in the mass spectrum. Additionally, this fast, automated peak picking algorithm was suitable for the analysis of a large set of samples.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.51.1-51.1
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• 2011

Red dusty Active Galactic Nuclei (AGNs) are suspected to mid-stage between ULIRG and AGN phase. As well as, red AGNs are suspected that they have more than 50% of whole AGN population. In order to understand the character of red AGNs, Black Hole (BH) mass of red AGN is a key property and can not measured by existing method such as reverberation mapping and single epoch method. Thus we still don't know their character and properties in clearly. To estimate properties of red AGNs without the effect of dust-obscuration, we have obtained Near InfraRed (NIR) spectra of 31 reverberation mapped AGNs and 49 Palomar-Green(PG) Quasi-Stellar Object (QSO) by using the infrared camera (IRC) for AKARI with unique wavelength range $2.5-5.0{\mu}m$. From this spectra, we measured the FWHM and luminosity of brackett ${\alpha}$ and ${\beta}$ at 4.0, 2.6 micron meter for deriving new BH mass estimators based on the properties of Brackett line emission.

• Bulletin of the Korean Chemical Society
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• v.21 no.8
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• pp.785-792
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• 2000

Mass spectral fragmentations of six chlorinated organophosphorus pesticides were investigated using electron impact mass spectrometry. Understanding the fragmentation pathways, based on the fragment ions of mass spectra, should be useful in the structural elucidation and chemical identification of these compounds. The pro-posed fragmentation pathways were verified by collision-induced dissociation B/E-linked scan spectra. ln most cases,the structures of characteristic fragment ions could be expected by the observation of the peak clusters due to 35Cl and 37Cl isotopes. According to substituted groups on phosphorus atom, phosphate and phospho-rothioate exhibited significantIy differentfragmentation patterns. Especially, phosphate and phosphorothioate with diethyl ester produced more diverse fragment ions than that with dimethyl ester.

• Bulletin of the Korean Chemical Society
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• v.18 no.6
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• pp.573-578
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• 1997

Ion fragmentations of fatty acids such as stearic acid, palmitic acid, myristic acid, and lauric acid were studied using mass spectrometry and semiempirical calculations. The mass spectra of fatty acids showed the distributions of CH₃(CH₂)$_n^+$ and $[(CH_2)_nCO_2H]^+$ fragment ions. The relative ion abundance distributions of $[(CH_2)_nCO_2H]^+$ showed the local maxima at n=6, 10, and 14. The local maximum phenomena were also found in the mass spectra of methyl stearate but not in those of normal alcohols. These local maxima could be explained not by heats of reaction for fragmentation but by the cyclic structures of the molecular ions. The AM1 semiempirical calculations for fatty acids clearly show that the linear structures are more favorable than the cyclic ones for neutral molecules while the cyclic structures are more favorable than the linear ones for ionic molecules. The distances between carboxyl group and methylene of the cylic structures of ionized fatty acids were calculated. The methylene carbons with n=6, 10, and 14 were closer to the carboxyl group than adjacent ones.