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201.
We consider scattering of a pulse propagating through a three-dimensional random media and study the shape of the pulse in the parabolic approximation. We show that, similarly to the one-dimensional O’Doherty–Anstey theory, the pulse undergoes a deterministic broadening. Its amplitude decays only algebraically and not exponentially in time, due to the signal low/midrange frequency component. We also argue that the parabolic approximation captures the front evolution (but not the signal away from the front) correctly even in the fully three-dimensional situation. 相似文献
202.
The theory of limits of dense graph sequences was initiated by Lovász and Szegedy in [8]. We give a possible generalization of this theory to multigraphs. Our proofs are based on the correspondence between dense graph limits and countable, exchangeable arrays of random variables observed by Diaconis and Janson in [5]. The main ingredient in the construction of the limit object is Aldous?? representation theorem for exchangeable arrays, see [1]. 相似文献
203.
204.
Journal of Solid State Electrochemistry - Thick lead dioxide layers were electrodeposited on gold and platinum substrates from aqueous solutions of Pb(NO3)2 dissolved in nitric acid and perchloric... 相似文献
205.
206.
A rapid and sensitive determination of hypoxic radiosensitizer agent nimorazole in rat plasma by LC‐MS/MS and its application to a pharmacokinetic study
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Subhradip Roychowdhury Manik Ghosh Barij Nayan Sinha Kishanta Kumar Pradhan Trishna Bal Venkateswari Muthukrishnan Julio A. Seijas Abhijit Pujarid 《Biomedical chromatography : BMC》2015,29(10):1575-1580
A highly sensitive, accurate and robust LC‐MS/MS method was developed and validated for determination of nimorazole (NMZ) in rat plasma using metronidazole (MNZ) as internal standard (IS). The analyte and IS were extracted from plasma by precipitating protein with acetonitrile and were chromatographed using an Agilent Poroshell 120, EC‐C18 column. The mobile phase was composed of a mixture of acetonitrile and 0.1 % formic acid (85:15 v/v). The total run time was 1.5 min and injection volume was 5 μL. Multiple reaction monitoring mode using the transitions of m/z 227.1 → m/z 114.0 for MNZ and m/z 172.10 → m/z 128.1 for IS were monitored on a triple quadrupole mass spectrometer, operating in positive ion mode. The calibration curve was linear in the range of 0.25–200 ng/mL (r2 > 0.9996) and the lower limit of quantification was 0.25 ng/mL in the rat plasma samples. Recoveries of NMZ ranged between 88.05 and 95.25%. The precision (intra‐day and inter‐day) and accuracy of the quality control samples were 1.25–8.20% and ?2.50–3.10, respectively. The analyte and IS were found to be stable during all sample storage and analysis procedures. The LC‐MS/MS method described here was validated and successfully applied to pharmacokinetic study in rats. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
207.
Balázs Molnár Gyula Simig Tibor Bakó András Dancsó Balázs Volk 《Tetrahedron letters》2012,53(23):2922-2924
A new and efficient synthesis of 5,6-diaminophthalide and a novel thiadiazolophthalide has been accomplished. Both molecules are useful starting compounds for the construction of more complex heterocyclic systems and for the preparation of bioisosteres of methylenedioxyphenyl derivatives. 相似文献
208.
Generation Expansion Planning Model Supporting Diverse Environmental Policies for Reduction of Greenhouse Gases
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The purpose of this paper is to a develop model for generation expansion planning that can support diverse environmental policies for the reduction of greenhouse gases (GHGs) of South Korea. South Korea is required to reduce its GHG emissions by 30% from the BAU level by 2020. The Wien Automatic System Planning Package currently used in South Korea has limitations in terms of the application of renewable energy policies and GHG targets; this paper proposes the use of an equipment planning model named generation and transmission expansion program, which has been developed to resolve such limitations. For verification of the model, a case study on the 6th Basic Plan of Long‐Term Electricity Supply and Demand has been conducted. The results show that for the year 2020 South Korea's annual GHG emissions will be 36.6% more than the GHG Target Management System (GHG TMS) target set for the same year (30%). To achieve the GHG TMS target, the costs involved amount to about 72 trillion KRW (70 billion USD). Consequently, the South Korean government needs to review the performability of this target. 相似文献
209.
A proper 2-tone k-coloring of a graph is a labeling of the vertices with elements from \({\binom{[k]}{2}}\) such that adjacent vertices receive disjoint labels and vertices distance 2 apart receive distinct labels. The 2-tone chromatic number of a graph G, denoted τ 2(G) is the smallest k such that G admits a proper 2-tone k coloring. In this paper, we prove that w.h.p. for \({p\geq Cn^{-1/4} {\rm ln}^{9/4}n, \tau_2(G_{n, p}) = (2 + o(1))\chi(G_{n, p})}\) where \({\chi}\) represents the ordinary chromatic number. For sparse random graphs with p = c/n, c constant, we prove that \({\tau_2(G_{n, p}) = \lceil{({\sqrt{8\Delta + 1} + 5})/{2}}}\) where Δ represents the maximum degree. For the more general concept of t-tone coloring, we achieve similar results. 相似文献
210.
H. J. Breunig L. Balázs N. Philipp A. Soran C. Silvestru 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):853-857
The homocycles (RBi)n (n = 3–5) react with MeC5 H4Mn(CO)2(thf) (thf = tetrahydrofuran) or Fe2(CO)9 to give Bi2[Mn(CO)2MeC5 H4]3 (1) or Bi2Fe3(CO)9 (3). Reaction of R4Bi2 (R = Me3SiCH2) with Fe2(CO)9 in toluene gives R2Bi2Fe2(CO)8 (4) and R4Bi2Fe(CO)4 (5). The heterocycles (RBiS)2(R = 2-(Me2NCH2)C6 H4 (6), 2, 6-(Me2NCH2)2 C6 H4 (7) are formed by reaction of the corresponding dihalides RBiCl2 with Na2S. The reaction of (RBiS)2(R = 2-(Me2NCH2)C6 H4) with W(CO)5(thf) leads to (RBiS)2[W(CO)5]2 (8). 相似文献