• Title/Summary/Keyword: Binary

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Assessment of Reliability when Using Diagnostic Binary Ratios of Polycyclic Aromatic Hydrocarbons in Ambient Air PM10

  • Pongpiachan, Siwatt
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.18
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    • pp.8605-8611
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    • 2016
  • The reliability of using diagnostic binary ratios of particulate carcinogenic polycyclic aromatic hydrocarbons (PAHs) as chemical tracers for source characterisation was assessed by collecting PM10 samples from various air quality observatory sites in Thailand. The major objectives of this research were to evaluate the effects of day and night on the alterations of six different PAH diagnostic binary ratios: An/(An + Phe), Fluo/(Fluo + Pyr), B[a]A/(B[a]A + Chry), B[a]P/(B[a]P + B[e]P), Ind/(Ind + B[g,h,i]P), and B[k]F/Ind, and to investigate the impacts of site-specific conditions on the alterations of PAH diagnostic binary ratios by applying the concept of the coefficient of divergence (COD). No significant differences between day and night were found for any of the diagnostic binary ratios of PAHs, which indicates that the photodecomposition process is of minor importance in terms of PAH reduction. Interestingly, comparatively high values of COD for An/(An + Phe) in PM10 collected from sites with heavy traffic and in residential zones underline the influence of heterogeneous reactions triggered by oxidising gaseous species from vehicular exhausts. Therefore, special attention must be paid when interpreting the data of these diagnostic binary ratios, particularly for cases of low-molecular-weight PAHs.

Type Ibc Supernova Progenitors in Binary Systems: Observational Constraints on the Progenitor Candidate of the Supernova iPTF13bvn

  • Kim, Hyun-Jeong;Yoon, Sung-Chul;Koo, Bon-Chul
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.85.1-85.1
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    • 2014
  • The progenitors of Type Ibc supernovae (SNe Ibc) have been believed to be massive Wolf-Rayet (WR) stars, formed either through stellar wind mass loss or Roche-lobe outflow in a binary system. But observations indicate that ordinary SNe Ibc have relatively low ejecta masses (~2 Msun), which is not compatible with the WR star scenario for SN Ibc progenitors. On the other hand, helium stars in binary systems which can be produced via mass transfer are also suggested as a possible candidate for SN Ibc progenitors. Binary star evolution models predict that SN Ibc progenitors having final masses of 3-7 Msun can be produced, but their observational properties are not well understood. In this study, we present the parameter study on the observational constraints of helium stars of 3-5 Msun in binary systems using evolutionary models and the atmospheric radiative transfer code CMFGEN. We present the predicted magnitudes and spectra of helium stars in optical bands for different wind velocity profiles and mass loss rates. We also present those observables of the progenitor binary system considering O-type companion stars. Based on the results, we discuss the expected observational properties of SN Ibc progenitors in binary systems. In particular, we discuss the constraints on the progenitor of the SN Ib iPTF13bvn of which progenitor candidate has been identified for the first time in pre-explosion images among SNe Ibc.

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Droplet Size and Thermal conductivity Measurements of Binary Nanoemulsion (이성분 나노에멀전의 입도 및 열전도도 측정)

  • Cho, Chang-Hwan;Sul, Hea-Youn;Jung, Jung-Yeul;Kang, Yong-Tae
    • Proceedings of the SAREK Conference
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    • 2009.06a
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    • pp.815-820
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    • 2009
  • Binary nanoemulsions which are defined as the, oil-droplet suspensions in binary solution ($H_2O$/LiBr), are developed to enhance the heat and mass transfer performance of absorption refrigeration systems. In this study, a novel two-step method is proposed to prepare the stable oil-in-binary solution (O/S) emulsion. Polymer is used as a steric stabilizer to stabilize the oil-droplets in a strong electrolyte ($H_2O$/LiBr). It is found that the thermal conductivity of the binary nanoemulsion is inversely proportional to the emulsion size while the concentrations of oil and $H_2O$/LiBr are less dominant for the thermal conductivity of binary nanoemulsions.

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A Study on Channel Estimation for High-speed Binary CDMA Systems (고속 Binary CDMA 시스템을 위한 채널 추정에 관한 연구)

  • Kang, Sung-Jin
    • Journal of Advanced Navigation Technology
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    • v.14 no.5
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    • pp.677-683
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    • 2010
  • In this paper, a channel estimation scheme for high-speed Binary CDMA systems is proposed and its performances are investigated. In high-speed Binary CDMA which adopt high order modulations, since BER(bit error rate) performances are deteriorated when equalizer does not converge enough during preamble period it is preferred to set the optimum coefficients of equalizer through channel estimation. In this paper, taking notice of repetition of CAZAC sequence in preamble period, a channel estimation scheme is proposed, which can improve estimation performances with few complexity increase. From the simulation results, one can see that the proposed channel estimation scheme can be implemented simply with no performance deterioration compared to the conventional one.

Viscosities of LaCl3-CsCl Binary Melts (LaCl3-CsCl 2성분계 용융염의 점도)

  • Kim, Kiho
    • Journal of the Korean institute of surface engineering
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    • v.46 no.2
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    • pp.87-92
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    • 2013
  • Viscosities of $LaCl_3$-CsCl binary melts were measured by the capillary method over the range of their liquidus temperatures to about 1200 K. The cell constant were determined by using pure water. The results obtained are summerized as follows: Viscosities of melted $LaCl_3$ were decreased with the content of CsCl for all over the composition range of binary melts. Composition versus viscosity relation for the binary melt showed a non-linear relationship from the additivity line and the deviations showed a maximum value at about 60 mol% CsCl. This suggest the existence of the complex ion of $LaCl_4{^-}$ in the melt. Activation energy for the viscous flow of the binary melts decreased monotonously with the increasing content of CsCl after a few increasement till 40 mol% CsCl. All of these results were the resemble with the viscosities of $LaCl_3$-NaCl binary melts.

CCD Photometry of Low Mass Ratio Contact Binary FP Boo - IV (질량비가 작은 접촉쌍성 FP Boo의 CCD 측광관측 - IV)

  • Oh, Kyu-Dong;Lee, Woo-Baik
    • Journal of Astronomy and Space Sciences
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    • v.26 no.1
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    • pp.1-8
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    • 2009
  • We present new B, V, and R CCD photometric light curves for the low mass ratio contact binary FP Boo. A new photometric solution and absolute physical dimensions of the system were derived by applying the Wilson-Devinney program to our observed light curves and to previously published Rucinski et al.'s radial velocity curves. From the H-R diagram of 24 low mass ratio contact binary system including FP Boo, the evolutionary stage of FP Boo was found to coincide with those of the general low mass ratio contact binary systems. The light curves obtained in this season show a small asymmetry in their shapes.

Evolution of primary stars in Pop III binary systems

  • Lee, Hunchul;Yoon, Sung-Chul
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.77.4-78
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    • 2016
  • Binary interactions may have significant impact on Pop III stellar evolution. Pop III single star evolution indicates that for primary masses less than $20M_{\odot}$, no significant binary mass transfer would occur before core helium exhaustion. We perform binary system evolution for various primary masses ($20M_{\odot}$ < $M_1$ < $60M_{\odot}$) and initial periods under same mass ratio $M_2/M_1=0.9$, and follow the evolution and mass transfer of the primary star. If binary mass transfer occurs during post main sequence, the primary star does not evolve into naked helium star and still contain significant hydrogen in the envelope. During the post mass transfer phase, the primary star evolves redward, and does not become sufficiently hot to enhance the number of ionizing photons, compared to the case of single star evolution for a given initial mass. This result implies that primary stars of massive Pop III binary systems would have little contribution to the reionization in the early universe. Given the large hydrogen content ($0.326-1.793M_{\odot}$), the primary stars that underwent stable mass transfers would explode as a Type IIb supernova, and it would be difficult for Pop III binary stars to produce Type Ib/c supernovae that look similar to those found in the local universe.

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Influence of granite waste aggregate on properties of binary blend self-compacting concrete

  • Jain, Abhishek;Gupta, Rajesh;Chaudhary, Sandeep
    • Advances in concrete construction
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    • v.10 no.2
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    • pp.127-140
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    • 2020
  • This study explores the feasibility of granite waste aggregate (GWA) as a partial replacement of natural fine aggregate (NFA) in binary blend self-compacting concrete (SCC) prepared with fly ash. Total of nine SCC mixtures were prepared wherein one was Ordinary Portland cement (OPC) based control SCC mixture and remaining were fly ash based binary blend SCC mixtures which included the various percentages of GWA. Fresh properties tests such as slump flow, T500, V-funnel, J-ring, L-box, U-box, segregation resistance, bleeding, fresh density, and loss of slump flow (with time) were conducted. Compressive strength and percentage of permeable voids were evaluated in the hardened state. All the SCC mixtures exhibited sufficient flowability, passing ability, and resistance to segregation. Besides, all the binary blend SCC mixtures exhibited lower fresh density and bleeding, and better residual slump (up to 50% of GWA) compared to the OPC based control SCC mixture. Binary blend SCC mixture incorporating up to 40% GWA provided higher compressive strength than binary blend control SCC mixture. The findings of this study encourage the utilization of GWA in the development of binary blend SCC mixtures with satisfactory workability characteristics as a replacement of NFA.

Thermal Conductivity measurement of Binary Nanofluids by the Transient Hot-wire Method (비정상 열선법을 이용한 이성분 나노유체의 열전도도 측정)

  • Cho, Chang-Hwan;Sul, Hea-Youn;Koo, June-Mo;Kang, Yong-Tae
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.165-169
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    • 2008
  • Binary nanofluids(Binary mixture + nanoparticles) have been extensively paid attention for application in absorption system as a new working fluid. Thermal property evaluation of the new refrigerants is inevitable to apply them for actual system. The objectives of this paper are to measure the thermal conductivity of the binary nanofluids by the transient hot-wire method, and to assess the application possibility of the binary nanofluids for absorption system. It was found that the thermal conductivity of the binary nanofluids ($H_2O/LiBrAl_2O_3$) increased with increasing the concentration of the nanoparticles ($Al_2O_3$) and enhanced up to 27% at 0.1 vol % of the nanoparticles.

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Phase Behavior of Binary and Ternary Blends Having the Same Chemical Components and Compositions

  • Yoo, Joung-Eun;Kim, Yong;Kim, Chang-Keun;Lee, Jae-Wook
    • Macromolecular Research
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    • v.11 no.5
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    • pp.303-310
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    • 2003
  • The phase behavior of binary blends of dimethylpolycarbonate-tetramethyl polycarbonate (DMPCTMPC) copolycarbonates and styrene-acrylonitrile (SAN) copolymers has been examined and then compared with that of DMPC/TMPC/SAN ternary blends having the same chemical components and compositions except that the DMPC and TMPC were present in the form of homopolymers. Both binary and ternary blends were miscible at certain blends compositions, and the miscible blends showed the LCST-type phase behavior or did not phase separated until thermal degradation temperature. The miscible region of binary blends is wider than that of the corresponding ternary blends. Furthermore, the phase-separation temperatures of miscible binary blends are higher than those of miscible ternary blends at the same chemical compositions. To explain the destabilization of polymer mixture with the increase of the number of component, interaction energies of binary pairs involved in these blends were calculated from the phase separation temperatures using lattice-fluid theory and then the phase stability conditions for the polymer mixture was analyzed with volume fluctuation thermodynamics.