• 제목/요약/키워드: DPC

검색결과 183건 처리시간 0.02초

Mixed Micellar Properties of DPC with Other Cationic Surfactants (DTAB, TTAB, and CDEAB) (DPC와 다른 양이온성 계면활성제(DTAB, TTAB 및 CDEAB)와의 혼합마이셀화에 관한 연구)

  • Lee, Byung Hwan
    • Journal of the Korean Chemical Society
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    • 제42권5호
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    • pp.519-525
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    • 1998
  • The critical micelle concentration $(CMC^{\ast})$ and the counterion binding constant (B) in a micellar state of the mixed surfactant systems of dodecylpyridinium chloride (DPC) with dodecyltrimethylammonium bromide (DTAB), tetradecyltrimethylammonium bromide (TTAB), and cetyldimethylethylammonium bromide (CDEAB) were determined at $25^{\circ}C$ as a function of ${\alpha}_1$ (the overall molc fraction of DPC) by the use of electric conductivity method. Various thermodynamic parameters $(X_{i},\;{\gamma}_{I},\;C_{i},\;a^{M}_{i}, \beta,\;{\Delta}H_{mix}, \;and\; {\Delta}G^{o}_{m})$ for the micellization of DPC/DTAB, DPC/TTAB, and DPC/CDEAB mixtures were calculated and analyzed for each system by means of the equations derived from the pseudophase separation model. The results show that the DPC/DTAB mixed system has the greatest deviation and the DPC/CDEAB mixed system has the smallest deviation from the ideal mixed micellar model.

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Many-to-Many Disjoint Path Covers in Double Loop Networks (이중 루프 네트워크의 다대다 서로소인 경로 커버)

  • Park Jung-Heum
    • Journal of KIISE:Computer Systems and Theory
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    • 제32권8호
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    • pp.426-431
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    • 2005
  • A many-to-many k-disjoint path cover (k-DPC) of a graph G is a set of k disjoint paths joining k distinct source-sink pairs in which each vertex of G is covered by a path. In this paper, we investigate many-to-many 2-DPC in a double loop network G(mn;1,m), and show that every nonbipartite G(mn;1,m), $m{\geq}3$, has 2-DPC joining any two source-sink pairs of vertices and that every bipartite G(mn;1,m) has 2-DPC joining any two source-sink pairs of black-white vertices and joining any Pairs of black-black and white-white vertices. G(mn;l,m) is bipartite if and only if n is odd and n is even.

Design of Wide - range Clock and Data Recovery Circuit based Dual-loop DLL using 2-step DPC (2-step DPC를 이용한 이중루프 DLL기반의 광대역 클록 데이터 복원회로 설계)

  • Jung, Ki-Sang;Kim, Kang-Jik;Ko, Gui-Han;Cho, Seong-Ik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • 제61권2호
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    • pp.324-328
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    • 2012
  • A recovered jitter of CDR(Clock and Data Recovery) Circuit based on Dual-loop DLL(Delay Locked Loop) for data recovery in high speed serial data communication is changed by depending on the input data and reference clock frequency. In this paper, 2-step DPC which has constant jitter performance for wide-range input frequency is proposed. The designed prototype 2-step CDR using proposed 2-step DPC has operation frequency between 200Mbps and 4Gbps. Average delay step of 2-step DPC is 10ps. Designed CDR circuit was tested with 0.18um CMOS process.

Reaction Kinetics for the Synthesis of Diphenyl Carbonate from Dimethyl Carbonate (디메틸 카보네이트(DMC)로부터 디페닐카보네이트(DPC) 합성을 위한 반응속도론)

  • Choi, Yu-Mi;Cho, Im-Pyo;Cho, Hoon;Lee, Jin-Hong;Han, Myung-Wan
    • Korean Chemical Engineering Research
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    • 제50권5호
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    • pp.766-771
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    • 2012
  • PC (polycarbonate) is one of the widely used engineering plastics. Polycarbonate (PC) is traditionally produced by the reaction of phosgene and bisphenol-A. This phosgene process has the disadvantage as the high toxicity and corrosiveness of phosgene. The main point of focus to overcome the disadvantage of phosgene based process has been a route through dimethyl carbonate (DMC) to diphenyl carbonate (DPC). In this paper, for the DPC synthesis reaction using PBO as a catalyst, the effect of reaction temperature, reactant ratio, catalyst concentration on the reaction yield was investigated. A kinetic model for the DPC synthesis reaction was proposed and kinetic parameters for the proposed model was determined from batch reactor experiments. The predicted results by the proposed model were in good agreement with the experimental results.

Thermodynamic Study on the Mixed Micellization of Cationic Surfactants DPC and TTAB (양이온 계면활성제인 DPC와 TTAB의 혼합마이셀화에 대한 열역학적 고찰)

  • Lee, Byung Hwan
    • Journal of the Korean Chemical Society
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    • 제43권6호
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    • pp.614-620
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    • 1999
  • The critical micelle concentration (CMC) and the counterion binding constant (${\beta}$) at the CMC of the mixtures of Dodecylpyridinium chloride (DPC) and Tetradecyltrimethylammonium bromide (TTAB) have been determined from the concentration dependence of electrical conductance at various temperatures from $4^{\circ}C$ to $36^{\circ}C$. Thermodynamic parameters (${\Delta}C_p$, ${\Delta}G^o_m$, ${\Delta}H^o_m$ and ${\Delta}S^o_m$), associated with the micelle formation of DPC/TTAB mixtures, have been estimated from the temperature dependence of CMC and ${\beta}$values. The measured values of ${\Delta}C_p$ and ${\Delta}G^o_m$ are negative but the values of ${\Delta}S^o_m$ are positive in the whole measured temperature region. The values of ${\Delta}H^o_m$ are positive at low temperature region and negative at high temperature region. The results show that all of the thermodynamic parameters are dependent on temperature and mole fraction of DPC(${\alpha}_DPC$).

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Triangulation Algorithm for Multi-user Spatial Multiplexing in MIMO Downlink Channels (MIMO 다운링크 채널에서 다중사용자 공간다중화를 위한 알고리즘)

  • Lee, Heun-Chul;Paulraj, Aroyaswami;Lee, In-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • 제35권1C호
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    • pp.45-54
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    • 2010
  • This paper studies the design of a multiuser multiple-input multiple-output (MIMO) system, where a base station (BS) transmits independent messages to multiple users. The remarkable "dirty paper coding (DPC)" result was first presented by Costa that the capacity does not change if the Gaussian interference is known at the transmitter noncausally. While several implementable DPC schemes have been proposed recently for single-user dirty-paper channels, DPC is still difficult to implement directly in practical multiuser MIMO channels. In this paper, we propose a network channel matrix triangulation (NMT) algorithm for utilizing interference known at the transmitter. The NMT algorithm decomposes a multiuser MIMO channel into a set of parallel, single-input single-output dirty-paper subchannels and then successively employs the DPC to each subchannel. This approach allows us to extend practical single-user DPC techniques to multiuser MIMO downlink cases. We present the sum rate analysis for the proposed scheme. Simulation results show that the proposed schemes approach the sum rate capacity of the multiuser MIMO downlink at moderate signal-to-noise ratio (SNR) values.

A Study on Distributed Power Control for Energy Efficiency in Multicast Routing (멀티캐스트 라우팅에서의 전력 분산 제어(DPC)에 관한 연구)

  • Chung, Hyun-Gi;Yang, Seung-In
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • 제17권10호
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    • pp.985-992
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    • 2006
  • The classic routing algorithms try to minimize the number of hops to reach a destination. In our DPC(Distributed Power Control) this hop-by-hop power level selection is also used to select the path guaranteeing low energy consumption. The main goal is to realize a dynamic protocol able to be aware of mobility and to automatically set security threshold in order to get the best performance in every situation. In conclusion, the simulation DPC has improved energy gain of the AMRIS routing algorithm at the narrow area, and ODMRP routing algorithm has improved energy gain at the wide area.

Comparative Study of Protein Profile during Development of Mouse Placenta

  • Han, Rong-Xun;Kim, Hong-Rye;Naruse, Kenji;Choi, Su-Min;Kim, Baek-Chul;Park, Chang-Sik;Jin, Dong-Il
    • Reproductive and Developmental Biology
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    • 제31권4호
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    • pp.253-260
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    • 2007
  • To examine the differential protein expression pattern in the 11.5 day post-coitus (dpc) and 18.5 dpc placenta of mouse, we have used the global proteomics approach by 2-D gel electrophoresis (2-DE) and MALDI-TOF-MS. The differential protein patterns of 3 placentae at the 11.5 dpc and 18.5 dpc from nature mating mice were analyzed. Proteins within isoelectric point range of $3.0{\sim}10.0$, separately were analyzed in 2DE with 3 replications of each sample. A total of approximately 1,600 spots were detected in placental 2-D gel stained with Coomassie-blue. In the comparison of 11.5 dpc and 18.5 dpc placentae, a total of 108 spots were identified as differentially expressed proteins, of which 51 spots were up-regulated proteins such as alpha-fetoprotein, mKIAA0635 protein and transferrin, annexin A5, while 48 spots were down-regulated proteins such as Pre-B-cell colony-enhancing factor l(PBEF), aldolase 1, A isoform, while 4 spots were 11.5 dpc specific proteins such as chaperonin and Acidic ribosomal phosphoprotein P0, while 3 spots were 18.5 dpc specific proteins such as aldo-keto reductase family 1, member B7 and CAST1/ERC2 splicing variant-1. Most identified proteins in this analysis appeared to be related with catabolism, cell growth, metabolism and regulation. Our results revealed composite profiles of key proteins involved in mouse placenta during pregnancy.

Formation of DNA-protein Cross-links Mediated by C1'-oxidized Abasic Lesion in Mouse Embryonic Fibroblast Cell-free Extracts

  • Sung, Jung-Suk;Park, In-Kook
    • Animal cells and systems
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    • 제9권2호
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    • pp.79-85
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    • 2005
  • Oxidized abasic residues arise as a major class of DNA damage by a variety of agents involving free radical attack and oxidation of deoxyribose sugar components. 2-deoxyribonolactone (dL) is a C1'-oxidized abasic lesion implicated in DNA strand scission, mutagenesis, and covalent DNA-protein cross-link (DPC). We show here that mammalian cell-free extract give rise to stable DPC formation that is specifically mediated by dL residue. When a duplex DNA containing dL at the site-specific position was incubated with cell-free extracts of Po ${\beta}-proficient$ and -deficient mouse embryonic fibroblast cells, the formation of major dL-mediated DPC was dependent on the presence of DNA polymerase (Pol) ${\beta}$. Formation of dL-specific DPC was also observed with histones and FEN1 nuclease, although the reactivity in forming dL-mediated DPC was significantly higher with Pol ${\beta}$ than with histones or FEN1. DNA repair assay with a defined DPC revealed that the dL lesion once cross-linked with Pol ${\beta}$ was resistant to nucleotide excision repair activity of cell-free extract. Analysis of nucleotide excision repair utilizing a model DNA substrate containing a (6-4) photoproduct suggested that excision process for DPC was inhibited because of DNA single-strand incision at 5' of the lesion. Consequently DPC mediated by dL lesion may not be readily repaired by DNA excision repair pathway but instead function as unusual DNA damage causing a prolonged DNA strand break and trapping of the major base excision repair enzyme.

Effect of n-Butanol on the Mixed Micellization of DPC with CDEAB (DPC와 CDEAB의 혼합마이셀화에 미치는 n-부탄올의 효과)

  • Lee, Byung-Hwan
    • Journal of the Korean Chemical Society
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    • 제48권3호
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    • pp.236-242
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    • 2004
  • The critical micelle concentration (CMC) and the counterion binding constant (B) in a mixed micellar state of the Dodecylpyridinium chloride (DPC) with the Cetyldimethylethylammonium bromide (CDEAB) at 25$^{\circ}C$ in aqueous solutions of n-butanol were determined as a function of ${\alpha}_1$ (the overall mole fraction of DPC) by the use of electric conductivity method. Various thermodynamic parameters (($X_i,\;{\gamma}_i,\;C_i,\;a^M_i,\;{\beta},\;and {\Delta}H_{mix})$were calculated by means of the equations derived from the nonideal mixed micellar model. The effect of n-butanol on the mixed micellization of the DPC/CDEAB mixtures has been also studied by analyzing the measured and calculated thermodynamic parameters (CMC, B 및 $;{\Delta}G_o\;^m$).