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241.
RN Mohapatra 《Pramana》2000,55(1-2):289-296
It is shown that if the supersymmetric Standard Model (MSSM) emerges as the low energy limit of a high scale left-right symmetric
gauge structure, the number of uncontrollable CP violating phases of MSSM are drastically reduced. In particular it guarantees
the vanishing of the dangerous phases that were at the root of the so called SUSY CP problem. Such a symmetric gauge structure
is independently motivated by the smallness of neutrino masses that arise via seesaw mechanism automatic in the theory. The
minimal version of this theory also provides an explanation of the smallness of ε′/ε as a consequence of the high scale parity
invariance.
This talk is based on work done in collaboration with K S Babu and B Dutta. 相似文献
242.
An organically templated iron(II) sulfate of the composition [H3N(CH2)2NH2(CH2)2(NH3]4[Fe(II)9F18(SO4)6].9H2O with a distorted Kagome structure has been synthesized under solvothermal conditions in the presence of diethylenetriamine. The distortion of the hexagonal bronze structure comes from the presence of two different types of connectivity between the FeF4O2 octahedra and the sulfate tetrahedra. This compound exhibits magnetic properties different from those of an Fe(II) compound with a perfect Kagome structure and is a canted antiferromagnet at low temperatures. 相似文献
243.
Meenu Thakur B. R. Behera Ruchi Mahajan N. Saneesh Gurpreet Kaur Priya Sharma R. Dubey Kushal Kapoor A. Yadav Neeraj Kumar S. Kumar Kavita Rani P. Sugathan A. Jhingan A. Chatterjee M. B. Chatterjee S. Mandal A. Saxena Santanu Pal S. Kailas Avazbek Nasirov Bakhodir Kayumov 《The European Physical Journal A - Hadrons and Nuclei》2017,53(6):133
244.
Buckling analysis of nanobeams with exponentially varying stiffness by differential quadrature method
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We present the application of differential quadrature(DQ) method for the buckling analysis of nanobeams with exponentially varying stiffness based on four different beam theories of Euler-Bernoulli, Timoshenko, Reddy, and Levison.The formulation is based on the nonlocal elasticity theory of Eringen. New results are presented for the guided and simply supported guided boundary conditions. Numerical results are obtained to investigate the effects of the nonlocal parameter,length-to-height ratio, boundary condition, and nonuniform parameter on the critical buckling load parameter. It is observed that the critical buckling load decreases with increase in the nonlocal parameter while the critical buckling load parameter increases with increase in the length-to-height ratio. 相似文献
245.
Polyacrylonitrile-based Zn–Al layered double hydroxide composites (PAN/LDH) have been synthesised with different LDH content by in situ polymerisation technique. The nanocomposites were systematically studied by Fourier transform infrared spectroscopy, X-ray diffraction (XRD), thermo gravimetric analysis (TGA), field emission scanning electron microscope (FE SEM), high resolution transmission electron microscopy (HRTEM), energy dispersive spectroscopy (EDS) and antibacterial activity measurement. The successful formation of exfoliated nanocomposite was inferred from the XRD patterns and HRTEM images. The thermal decomposition of PAN was enhanced upon nanocomposite (PAN/LDH) formation. The antimicrobial activity of PAN/LDH nanocomposites is evaluated for antibacterial activity against some clinically important bacterial pathogens and the bacterial growth is monitored at different percentage of LDH. The PAN/LDH composites displayed considerable antibacterial activity, on the contrary the virgin PAN did not possess any antibacterial activity. The likely electrostatic interaction among LDH layers with charged surface of bacterial cell is assumed to be responsible for antimicrobial activity. The prepared nanocomposite has appreciable thermal stability in combination with antibacterial activities by which the material is suitable for packaging and fabrication in textile application. 相似文献
246.
The dimension function Dψ of a band-limited wavelet ψ is bounded by n if its Fourier transform is supported in [−(2n+2/3)π,(2n+2/3)π]. For each
and for each , 0<<δ=δ(n), we construct a wavelet ψ with supp
such that Dψ>n on a set of positive measure, which proves that [−(2n+2/3)π,(2n+2/3)π] is the largest symmetric interval for estimating the dimension function by n. This construction also provides a family of (uncountably many) wavelet sets each consisting of infinite number of intervals. 相似文献
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247.
Abe K Abe K Abe R Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Behari S Behera PK Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Danilov M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Everton CW Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Gotow K Guo R Haba J Hamasaki H Handa F Hara K Hara T Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T 《Physical review letters》2002,88(18):181803
We report the observation of the decay mode B(+/-) --> p(-)pK(+/-)based on an analysis of 29.4 fb(-1) of data collected by the Belle detector at KEKB. This is the first example of a b-->s transition with baryons in the final state. The p(-)p mass spectrum in this decay is inconsistent with phase space and is peaked at low mass. The branching fraction for this decay is measured to be B(B+/--->p(-)pK+/-) = [4.3(+1.1)(-0.9)(stat)+/-0.5(syst)]x 10(-6). We also report upper limits for the decays B(0)-->p(-)pK(S) and B(+/-)-->p(-)p pi(+/-). 相似文献
248.
Abe K Abe K Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Bedny I Behari S Behera PK Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Danilov M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Everton CW Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Golob B Gordon A Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M 《Physical review letters》2002,89(7):071801
We present a measurement of CP-violating asymmetries in B0-->pi(+)pi(-) decays based on a 41.8 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We fully reconstruct one neutral B meson as a B0-->pi(+)pi(-) CP eigenstate and identify the flavor of the accompanying B meson from its decay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we obtain the CP-violating asymmetry parameters S(pipi)=-1.21(+0.38)(-0.27)(stat)+0.16-0.13(syst) and A(pipi)=+0.94(+0.25)(-0.31)(stat)+/-0.09(syst). 相似文献
249.
Abe K Abe K Abe R Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Behari S Behera PK Bondar A Bozek A Browder TE Casey BC Chao Y Cheon BG Chistov R Choi Y Dong LY Eidelman S Eiges V Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Gordon A Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hojo T Hokuue T Hoshi Y Hoshina K Hou SR Hou WS Hsu SC Huang HC Igarashi Y 《Physical review letters》2002,88(16):162001
We report a measurement of the D0-D macro(0) mixing parameter y(CP) using 23.4 fb(-1) of data collected near the Upsilon(4S) resonance with the Belle detector at KEKB. y(CP) is measured from the lifetime difference of D0 mesons decaying into the K(-)pi(+) state and the CP-even eigenstate K(-)K(+). We find y(CP) = (-0.5+/-1.0(+0.7)(-0.8))x10(-2), where the first error is statistical and the second is systematic, corresponding to a 95% confidence interval -0.030相似文献
250.
The rates of hydrolysis of N-(2&4-hydroxybenzylidene)-2-aminobenzothiazoles has been studied in the pH range 4–13 in a 10% dioxane-water system and in various nonionic surfactant systems. The reaction is found to be due to water mediated intramolecular general base catalysis within the pH range 4.0 to 12.0 and due to nucleophilic catalysis beyond pH 12.0. A ten membered intermediate facilitating transannular attack of a water molecule on the methine carbon forming a naphthalene type transition state has been proposed. The reactivity difference in water and nonionic surfactants has been explained by a suitable entrapment model. 相似文献