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We derive an algorithm for solving the initial value problem for ut = ½σ2uxx + f(u)ux. The approach is based on the representation of the solution to the above equation in the form of the functional of Brownian motion. For small σ we get the approximation for ut = f(u)ux. A comparison with the random choice method is illustrated by the numerical example.  相似文献   
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The methodology for the determination of perfluorooctanoate (C(7)F(15)COO-, PFO), fluorotelomer alcohols (FTOHs: 6-2, 8-2, and 10-2), perfluorooctyl iodide (PFOI), and 8-2-8 fluorotelomer alcohol ester in complex fluorotelomer-based commercial products has been demonstrated and validated. Sample preparation procedures allowing determination of residual levels of these compounds were developed. The analytes were detected either by LC/MS/MS (PFO), LC/MS (FTOHs), or GC/MS (PFOI, 8-2-8 ester). The methods were validated by investigating the recoveries of analytes spiked at multiple levels to authentic sample matrices. The recoveries generally were between 70 and 130%. The limits of detection were in sub-microg/g range and the limits of quantitation were in the mug/g range. The methods were applied to fluorotelomer-based raw materials and fluorotelomer-based surfactants and polymeric products and represent methods useful for the determination of higher carbon chain length homologs as well.  相似文献   
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Consider a path-integral which is the solution to a diffusion version of the generalized Schro¨dinger's equation . Here , where A is an infinitesimal generator of a strongly continuous Markov Semigroup corresponding to the diffusion process . For and V replaced by one obtains , which represents a quantum mechanical Hamiltonian corresponding to a particle of mass 1 (in atomic units) subject to interaction with potential V. This paper is concerned with computer calculations of the second eigenvalue of by generating a large number of trajectories of an ergodic diffusion process.  相似文献   
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In addition to crown ethers and glymes which catalyze the phase transfer Gomberg-Bachmann reaction, quaternary salts, carboxylate anions, and acetonitrile cosolvent are all shown to be effective in this system.  相似文献   
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