Observation of multipactor in an alumina-based dielectric-loaded accelerating structure

We report a new regime of single-surface multipactor that was observed during high-power testing of an 11.424-GHz alumina-based dielectric-loaded accelerating structure. Previous experimental observations of single-surface multipactor on a dielectric occurred in cases for which the rf electric field was tangential and the rf power flow was normal to the dielectric surface (such as on rf windows) and found that the fraction of power absorbed at saturation is approximately 1%, independent of the incident power. In this new regime, in which strong normal and tangential rf electric fields are present and the power flow is parallel to the surface, the fraction of power absorbed at saturation is an increasing function of the incident power, and more than half of the incident power can be absorbed. A simple model is presented to explain the experimental results.     

Quasiparticle liquid in the highly overdoped Bi(2)Sr(2)CaCu(2)O(8+delta)

Results from the study of a highly overdoped (OD) Bi(2)Sr(2)CaCu(2)O(8+delta) with a T(c) = 51 K using angle-resolved photoemission spectroscopy are presented. We observe a sharp peak in the spectra near ( pi,0) that persists well above T(c), a nodal self-energy which approaches that seen for the Mo(110) surface state, and a more k-independent line shape at the Fermi surface than the lower-doped cuprates. This allows for a realistic comparison of the lifetime values to the experimental resistivity measurements. These observations point to the validity of the quasiparticle picture for the OD even in the normal state.     

Amphetamine-type stimulants (ATS) drug classification using shallow one-dimensional convolutional neural network

Molecular Diversity - Amphetamine-type stimulants (ATS) drug analysis and identification are challenging and critical nowadays with the emergence production of new synthetic ATS drugs with...     

Holographic screening length in a hot plasma of two sphere

We study the screening length \(L_{\mathrm{max}}\) of a moving quark–antiquark pair in a hot plasma, which lives in a two sphere, \(S^2\), using the AdS/CFT correspondence in which the corresponding background metric is the four-dimensional Schwarzschild–AdS black hole. The geodesic of both ends of the string at the boundary, interpreted as the quark–antiquark pair, is given by a stationary motion in the equatorial plane by which the separation length L of both ends of the string is parallel to the angular velocity \(\omega \). The screening length and total energy H of the quark–antiquark pair are computed numerically and show that the plots are bounded from below by some functions related to the momentum transfer \(P_c\) of the drag force configuration. We compare the result by computing the screening length in the reference frame of the moving quark–antiquark pair, in which the background metrics are “Boost-AdS” and Kerr–AdS black holes. Comparing both black holes, we argue that the mass parameters \(M_{\mathrm{Sch}}\) of the Schwarzschild–AdS black hole and \(M_{\mathrm{Kerr}}\) of the Kerr–AdS black hole are related at high temperature by \(M_{\mathrm{Kerr}}=M_{\mathrm{Sch}}(1-a^2l^2)^{3/2}\), where a is the angular momentum parameter and l is the AdS curvature.     

Performance Analysis of Compressed Sensing Given Insufficient Random Measurements

Most of the literature on compressed sensing has not paid enough attention to scenarios in which the number of acquired measurements is insufficient to satisfy minimal exact reconstruction requirements. In practice, encountering such scenarios is highly likely, either intentionally or unintentionally, that is, due to high sensing cost or to the lack of knowledge of signal properties. We analyze signal reconstruction performance in this setting. The main result is an expression of the reconstruction error as a function of the number of acquired measurements.     

Effects of pure AcOH and mixed AcOH–CS (CS?=?CH3CN and THF) solvents on the rate of cleavage of phthalic anhydride (PAn)

The values of pseudo-first-order rate constants (k _obs) for the acetolysis of phthalic anhydride (PAn) increase from 6.60?×?10^?7 to 31.5?×?10^?7?s^?1 with the increase in temperature from 30 to 50?°C. These values of k _obs give activation parameters ?H* and ?S* as 14.4?±?0.4?kcal?mol^?1 and ?39.1?±?1.3?cal?K^?1?mol^?1, respectively. The values of k _obs remain essentially unchanged with the increase in the content of CS (CS?=?CH₃CN or THF) from 0 to 40?% v/v in mixed AcOH?CCS solvents. These observations have been explained qualitatively.