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51.
52.
Journal of High Energy Physics - The results of many LHC searches for supersymmetric particles are interpreted using simplified models, in which one fixes the masses and couplings of most... 相似文献
53.
Attachment of Poly(l‐lactide) Nanoparticles to Plasma‐Treated Non‐Woven Polymer Fabrics Using Inkjet Printing 下载免费PDF全文
54.
It is shown that the bicyclic triaminophosphine P(i-BuNCH2CH2)3N serves as an effective ligand for the palladium-catalyzed amination of a wide array of aryl bromides and iodides. Other bicyclic or acyclic triaminophosphines, even those of similar basicity and/or bulk, were inferior. 相似文献
55.
C. Devendranath Reddy P. Mallikarjuna Reddy D. Ramasubba Reddy M. Nagalakshmamma K. Anuradha C. Naga Raju K. Darrell Berlin Kevin M. Couch Sameer Tyagi 《Journal of heterocyclic chemistry》1995,32(5):1483-1487
The synthesis of new 2,10-dichloro-6-aryloxy-12H-dibenzo[d,g][1,3,2]dioxaphosphocin 6-sulfides 4 was achieved in two steps with high yields from the simple materials 5,5′-dichloro-2,2′-dihydroxydiphenyl-methane (1) and thiophosphoryl chloride (2) which produced the key intermediate 2,6,10-trichloro-12H-dibenzo[d,g][1,3,2]dioxaphosphocin 6-sulfide (3) . Treatment of 3 with substituted phenols under phase transfer catalytic (PTC) conditions led to members of 4 . Long range coupling [5J(P,H) = 3.6 Hz] was observed between phosphorus and one of the bridged methylene protons in 4 . A 13C nmr analysis revealed 2J(P,O,C), 3J(P,O,C) 4J(P,O,C) and 5J(P,O,C) couplings. All 31P nmr chemical shifts for thirteen members of these new heterocycles are reported for the first time. The nmr data are not totally definitive to confirm a boat-chair as the major conformer for the central eight-membered dioxaphosphocin ring, but such a conformer is tentatively suggested as favored. 相似文献
56.
Mahmoud EL-Morshedy Fahad Sameer Alshammari Abhishek Tyagi Iberahim Elbatal Yasser S. Hamed Mohamed S. Eliwa 《Entropy (Basel, Switzerland)》2021,23(4)
In this article, we have proposed a new generalization of the odd Weibull-G family by consolidating two notable families of distributions. We have derived various mathematical properties of the proposed family, including quantile function, skewness, kurtosis, moments, incomplete moments, mean deviation, Bonferroni and Lorenz curves, probability weighted moments, moments of (reversed) residual lifetime, entropy and order statistics. After producing the general class, two of the corresponding parametric statistical models are outlined. The hazard rate function of the sub-models can take a variety of shapes such as increasing, decreasing, unimodal, and Bathtub shaped, for different values of the parameters. Furthermore, the sub-models of the introduced family are also capable of modelling symmetric and skewed data. The parameter estimation of the special models are discussed by numerous methods, namely, the maximum likelihood, simple least squares, weighted least squares, Cramér-von Mises, and Bayesian estimation. Under the Bayesian framework, we have used informative and non-informative priors to obtain Bayes estimates of unknown parameters with the squared error and generalized entropy loss functions. An extensive Monte Carlo simulation is conducted to assess the effectiveness of these estimation techniques. The applicability of two sub-models of the proposed family is illustrated by means of two real data sets. 相似文献
57.
Y B S R Prasad V K Senecha H C Pant M P Kamath G S Solanki P K Tripathi A P Kulkarni S Gupta R Pareek A S Joshi N Sreedhar Sameer Nigam C P Navathe 《Pramana》2000,55(5-6):797-802
The x-ray emission from slab targets of copper irradiated by Nd:glass laser (1.054 μm, 5 and 15 ns) at intensities between 1012 and 1011W/cm2 has been studied. The x-ray emissions were monitored with the help of high quantum efficiency x-ray silicon photo diodes
and vacuum photo diodes, all covered with aluminium filters of different thickness. The x-ray intensity vs the laser intensity
has a scaling factor of (1.2–1.92). The relative x-ray conversion efficiency follows an empirical relationship which is in
close agreement with the one reported by Babonneau et al. The ion velocities were monitored using Langmuir probes placed at different angles and radial distances from the target
position. The variation of the ion velocity with the laser intensity follows a scaling of the form Φ
β
where β ∼0.22 which is in good agreement with the reported scaling factor values. The results on the x-ray emission from Cu plasma
are reported. 相似文献
58.
We report on the degradation of the zero-voltage supercurrent generated in a Josephson tunnel junction residing in an asymmetric potential of the ratchet type, and driven by a quasiperiodic external signal having incommensurable frequencies with irrational ratio ω2/ω1 equals to the Golden Mean. In the underdamped regime and via computing the current–voltage (I–V) characteristic curves, we demonstrate that the disappearance of the superconducting state can be correlated to chaotic behaviour, where dynamical phase fluctuations and symmetry breakings associated with the potential and modulating signal are substantially taking place. 相似文献
59.
The Klein-Gordon equation in D-dimensions for a recently proposed ring-shaped Kratzer potential is solved analytically by
means of the conventional Nikiforov-Uvarov method. The exact energy bound states and the corresponding wave functions of the
Klein-Gordon are obtained in the presence of the non-central equal scalar and vector potentials. The results obtained in this
work are more general and can be reduced to the standard forms in three dimensions given by other works.
相似文献
60.
We experimentally investigate theoretical predictions of universal impedance fluctuations in wave chaotic systems using a microwave analog of a quantum chaotic infinite square well potential. We emphasize the use of the radiation impedance to remove the nonuniversal effects of the particular coupling between the outside world and the scatterer. Specific predictions that we test include the probability density functions (PDFs) of the real and imaginary parts of the universal impedance, the equality of the variances of these PDFs, and the dependence of these PDFs on a single loss parameter. 相似文献