• Title/Summary/Keyword: Multi-species

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Numerical Simulation of Auto-ignition Process of Diesel Sprays Using Detailed Chemistry and Representative Flamelet Model (상세 화학 반응 모델 및 RIF 모델을 이용한 디젤 분무의 자발화 과정 해석)

  • Yu, Y.W.;Kim, S.K.;Kim, Y.M.;Soh, J.L.
    • Journal of ILASS-Korea
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    • v.5 no.2
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    • pp.61-67
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    • 2000
  • The interaction between chemistry and turbulence is treated by employing the Representative Interactive Flamelet (RIF) Model. The detailed chemistry of 114 elementary steps and 44 chemical species is adopted for the n-heptane/air reaction. In order to account for the spatial inhomogeneity of the scalar dissipation rate, the multi-RIF is used. The effect of the number of RIF on ignition delay is discussed in detail. Numerical results indicate that the present RIF approach successfully predicts the ignition delay time as well as the essential features of a spray auto-ignition process.

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중금속으로 오염된 사격장토의 동전기 정화 -실내 파일롯 실험 중심으로-

  • 한상재;김병일;이정철;김수삼
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.69-72
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    • 2003
  • The purpose of this study is the development of hybrid horizontal electrokinetic(EK) remediation system on rifle range soil under unsaturated conditions. In order to remediate soil polluted by multi-species heavy metals, in pi]of scale, a series of EK remediation tests are carried out. PVC and PDB(Plastic Drain Board) electrode systems that connected with the power supply of constant voltage and vacuum pressure of 0.5kgf/$\textrm{cm}^2$ are installed, The test results showed that the pH distribution in the sample is below 8, which is maintained until the test is finished, because of the injection of flushing solution. The final concentration, which is normalized by initial concentration, is ranged about 50 to 90%.

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NUMERICAL SIMULATION OF THERMOCHEMICAL NON-EQUILIBRIUM FLOW AROUND BLUNT BODIES CONSIDERING CATALYTIC WALL EFFECTS (촉매벽 효과를 고려한 무딘 물체 주위의 열화학적 비평형 유동에 대한 수치적 연구)

  • Kim, J.W.;Kwon, O.J.
    • Journal of computational fluids engineering
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    • v.18 no.3
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    • pp.87-93
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    • 2013
  • A computational study has been performed to examine the effects of catalytic walls on the stagnation region heat transfer. The boundary conditions for none, finite, and fully catalytic walls have been incorporated into a multi-block compressible Navier-Stokes solver. In the present study, both chemical and thermal non-equilibrium effects were included. The flows over a blunt body model were simulated by varying surface catalytic recombination rates. A full range of catalycities was explored in the context of a constant wall temperature assumption. Detailed information on species concentrations, temperature, and surface heat flux are presented. Comparison with available flight data of surface heat flux is also made.

WAVEs: A Novel and Promising Weapon in the Cancer Therapy Tool Box

  • Sakthivel, K.M.;Prabhu, V. Vinod;Guruvayoorappan, C.
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.1719-1722
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    • 2012
  • The Wiskott-Aldrich Syndrome Protein family Verprolin - homologous proteins (WAVEs), encoded by a metastasis promoter gene, play considerable roles in adhesion of immune cells, cell proliferation, migration and destruction of foreign agents by reactive oxygen species. These diverse functions have lead to the hypothesis that WAVE proteins have multi-functional roles in regulating cancer invasiveness, metastasis, development of tumor vasculature and angiogenesis. Differentials in expression of WAVE proteins are associated with a number of neoplasms include colorectal cancer, hepatocellular cancer, lung squamous cell carcinoma, human breast adenocarcinoma and prostate cancer. In this review we attempt to unify our knowledge regarding WAVE proteins, focusing on their potentials as diagnostic markers and molecular targets for cancer therapy.

Meta Analysis to Draw the Appropriate Regimen of Enzyme and Probiotic Supplementation to Pigs and Chicken Diets

  • Ohh, Sang-Jip
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.4
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    • pp.573-586
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    • 2011
  • Along with the recent changes in animal feed supply circumstances, many enzyme and probiotic feed supplements have been introduced and applied to pigs and chicken diets. Therefore, both selection of the appropriate feed supplements and their proper supplementation becomes critical to justify the supplementation. Meta-analysis was proposed as an appropriate tool to assess the large amount of relevant information. In this review, reliable data from recent publications was compounded then analyzed to determine the best practice of effective enzyme supplementation from the perspectives of animal species, age, characteristics of feed, target substrates, optimum multi enzymes combination and intended objectives. The results of the analysis suggested pratical methods of probiotic supplementation regarding intestinal microbiota, physiological limitation of probiotics, maximization of the probiotic benefit and synergism with prebiotic supplements.

Micro-PIXE as a Technique for Multi-elemental Detection and Localization in Various Atmospheric Environmental Samples

  • Ma, Chang-Jin;Choi, Sung-Boo
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.E1
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    • pp.54-62
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    • 2008
  • Microbeam PIXE, often called micro-PIXE, is one of powerful tools for analyzing a wide range of elements for various samples. Moreover, it has important applications of interest to the atmospheric science. In the present study, a qualitative elemental imagination for various atmospheric environmental species was attempted using micro-PIXE. Especially, in combination with a novel individual droplet collection method and the micro-PIXE analytical technique, the chemical specification of various individual atmospheric samples could be carried out. Here, we briefly introduce the results of an application of micro-PIXE to the study of atmospheric environment. The detailed spatial resolution of multiple elements for various samples like individual ambient particles, individual raindrops, individual fog droplets, and individual snow crystals could be successfully achieved by scanning 2.6 MeV $H^+$ micro beam ($1{\sim}2{\mu}m$) accelerated by 3 MeV single-end accelerator.

The Heterochromatin Protein 1 (HP1) Family: Put Away a Bias toward HP1

  • Kwon, So Hee;Workman, Jerry L.
    • Molecules and Cells
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    • v.26 no.3
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    • pp.217-227
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    • 2008
  • Heterochromatin protein 1 (HP1) was first described in Drosophila melanogaster as a heterochromatin associated protein with dose-dependent effect on gene silencing. The HP1 family is evolutionarily highly conserved and there are multiple members within the same species. The multi-functionality of HP1 reflects its ability to interact with diverse nuclear proteins, ranging from histones and transcriptional co-repressors to cohesion and DNA replication factors. As its name suggests, HP1 is well-known as a silencing protein found at pericentromeres and telomeres. In contrast to previous views that heterochromatin is transcriptionally inactive; noncoding RNAs transcribed from heterochromatic DNA repeats regulates the assembly and function of heterochromatin ranging from fission yeast to animals. Moreover, more recent progress has shed light on the paradoxical properties of HP1 in the nucleus and has revealed, unexpectedly, its existence in the euchromatin. Therefore, HP1 proteins might participate in both transcription repression in heterochromatin and euchromatin.

Comparison of Exon-boundary Old and Young Domains during Metazoan Evolution

  • Lee, Byung-Wook
    • Genomics & Informatics
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    • v.7 no.2
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    • pp.131-135
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    • 2009
  • Domains are the building blocks of proteins. Exon shuffling is an important mechanism accounting for combination of a limited repertoire of protein domains in the evolution of multicellular species. A relative excess of domains encoded by symmetric exons in metazoan phyla has been presented as evidence of exon shuffling, and symmetric domains can be divided into old and new domains by determining the ages of the domains. In this report, we compare the spread, versatility, and subcellular localization of old and new domains by analyzing eight metazoan genomes and their respective annotated proteomes. We found that new domains have been expanding as multicellular organisms evolved, and this expansion was principally because of increases in class 1-1 domains amongst several classes of domain families. We also found that younger domains have been expanding in membranes and secreted proteins along with multi-cellular organism evolution. In contrast, old domains are located mainly in nuclear and cytoplasmic proteins. We conclude that the increasing mobility and versatility of new domains, in contrast to old domains, plays a significant role in metazoan evolution, facilitating the creation of secreted and transmembrane multidomain proteins unique to metazoa.

Carbon Nanotube Synthesis with High Purity by Introducing of NH3 Etching Gas (암모니아 식각 가스 도입에 의한 고순도 탄소나노튜브의 합성)

  • Lee, Sunwoo;Lee, Boong-Joo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.6
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    • pp.782-785
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    • 2013
  • Multi-walled carbon nanotubes were synthesized on Ni catalyst using thermal chemical vapor deposition. By introducing ammonia gas during the CNT synthesis process, clean and vertically aligned CNTs without impurities could be prepared. As the ammonia gas increased a partial pressure of hydrogen in the mixed gas during the CNT synthesis process, we could control the CNT synthesis rate appropriately. As the ammonia gas has an etching ability, amorphous carbon species covering the catalyst particles were effectively removed. Therefore catalyst particles could maintain their catalytic state actively during the synthesis process. Finally, we could obtain clean and vertically aligned CNTs by introducing $NH_3$ gas during the CNT synthesis process.

Phage Litmus: Biomimetic Virus-Based Colorimetric Sensors for Explosive Detection

  • O, Jin-U
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.90.1-90.1
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    • 2013
  • Nature utilizes various of the colorization process. Some species of birds can express their mood of tempers by changing their collagen structures on skin. For example, turkey can change their skin color by expansion of the collagen structures, which are associated with the distinct color changes. Here, we developed bioinspired virus-based colorimetric sensors which can be genetically tuned for target molecule. Using M 13 bacteriophage, we fabricated responsive self-assembled color matrices composed of quasi-ordered fiber bundle structures. These virus matrices can exhibit color change by stimuli through fiber bundle structure modulation. Upon exposure of volatile organic compounds, the resulting multi-colored matrices exhibited distinct color changes with different ratios that can be recognized by the naked eyes. Using the directed evolutionary approaches, we genetically engineered the virus matrix to incorporate binding motif for explosive detection (i.e., trinitrotoluene (TNT)). Through utilizing a common handheld device (i.e., iPhone), we could distinguish TNT molecules down to 20 ppb in a selective manner. Our novel biomimetic virus colorimetric sensor can overcome current limitation for low response selectivity.

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