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Russian Journal of General Chemistry - In the present study novel 1,2,4-oxadiazolo sulfonamides 3a–3o are synthesized by an efficient method based on the reaction of 1,2,4-oxadiazole amines...  相似文献   
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Russian Journal of Organic Chemistry - tert-Butyl 4-[(E)-but-1-en-3-yn-1-yl]-3-{[tert-butyl(dimethyl)silyl]oxy}-1H-indole-1-carboxylate has been synthesized with a good yield and selectivity...  相似文献   
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The third-order nonlinear optical properties of newly synthesized soluble polyoxadiazoles containing 3,4-dialkoxythiophenes were investigated by using Z-scan and degenerate four-wave mixing (DFWM) techniques. The measurements were performed at 532 nm with 7 ns pulses from a Nd:YAG laser. We found a good agreement between the values of χ(3) determined from both the experiments. Z-scan results indicate a negative nonlinear refractive index, n2, whose magnitude is of the order of 10−10 esu for all the copolymers. The variation of nonlinear response among the copolymers clearly indicates the dependence of χ(3) on donor and acceptor type of units present in these copolymers. The copolymers exhibit strong reverse saturable absorption and good optical limiting properties at 532 nm.  相似文献   
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We describe a two-chain model for soft multiparticle production in hadronic collisions. The model is formulated in a parton framework and is consistent with the dual topological scheme for the Pomeron. The sole inputs are valence quark structure functions in the colliding hadrons and parton fragmentation functions, both of which are known from “hard” processes. Our model, which contains no adjustable parameters, reproduces the shape, the energy dependence, and the normalization of inclusive spectra both in the central region and in the fragmentation region. The model provides a natural explanation for the ratio of πp topp cross sections.  相似文献   
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We use the formalism of supersymmetric quantum mechanics to enlarge considerably the limited class of analytically solvable one-dimensional periodic potentials. In particular, we derive and discuss the energy-band structure of the Lamé potentials pm sn2 (x, m) and associated Lamé potentials pm sn2 (x, m) + qm cn2(x, m)/dn2 (x, m), both of which involve Jacobi elliptic functions with modulus parameter m. We find several new analytic expressions for band-edge energies and wave functions. The supersymmetric partners of Lamé and associated Lamé potentials constitute even more new solvable potentials with exactly the same energy-band structure.  相似文献   
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Recent proton-proton scattering experiments from the CERN ISR show several striking features. There is strong evidence that the total cross section is rising. The elastic differential cross section shows a break in the forward slope, as well as a pronounced dip-bump structure, with the dip located at t ? ? 1.3 (GeV/c)2. We demonstrate that all these features and their energy dependence can be simultaneously and quantitatively very well described within the framework of Gribov reggeon calculus.  相似文献   
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Let Y1,…, Yn be independent identically distributed random variables with distribution function F(x, θ), θ = (θ′1, θ′2), where θi (i = 1, 2) is a vector of pi components, p = p1 + p2 and for θI, an open interval in p, F(x, θ) is continuous. In the present paper the author shows that the asymptotic distribution of modified Cramér-Smirnov statistic under Hn: θ1 = θ10 + n−1/2γ, θ2 unspecified, where γ is a given vector independent of n, is the distribution of a sum of weighted noncentral χ12 variables whose weights are eigenvalues of a covariance function of a Gaussian process and noncentrality parameters are Fourier coefficients of the mean function of the Gaussian process. Further, the author exploits the special form of the covariance function by using perturbation theory to obtain the noncentrality parameters and the weights. The technique is applicable to other goodness-of-fit statistics such as U2 [G. S. Watson, Biometrika 48 (1961), 109–114].  相似文献   
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