An exploding glass ?

We propose a connection between self-similar, focusing dynamics in nonlinear partial differential equations (PDEs) and macroscopic dynamic features of the glass transition. In particular, we explore the divergence of the appropriate relaxation times in the case of hard spheres as the limit of random close packing is approached. We illustrate the analogy in the critical case, and suggest a ``normal form'' that can capture the onset of dynamic self-similarity in both phenomena.Comment: 8 pages, 2 figure

Formation of dense partonic matter in relativistic nucleus-nucleus collisions at RHIC: Experimental evaluation by the PHENIX collaboration

Extensive experimental data from high-energy nucleus-nucleus collisions were recorded using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC). The comprehensive set of measurements from the first three years of RHIC operation includes charged particle multiplicities, transverse energy, yield ratios and spectra of identified hadrons in a wide range of transverse momenta (p_T), elliptic flow, two-particle correlations, non-statistical fluctuations, and suppression of particle production at high p_T. The results are examined with an emphasis on implications for the formation of a new state of dense matter. We find that the state of matter created at RHIC cannot be described in terms of ordinary color neutral hadrons.Comment: 510 authors, 127 pages text, 56 figures, 1 tables, LaTeX. Submitted to Nuclear Physics A as a regular article; v3 has minor changes in response to referee comments. Plain text data tables for the points plotted in figures for this and previous PHENIX publications are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm

Perfecting evaluation methods of energy equipment technical condition and resource based on electromagnetic-acoustic effect

To assess the technical condition and resource for the safe operation of electric and electrical equipment, it is proposed to use the electromagnetic-acoustic effect and the dynamic identification method based on the analysis of the coordinates of the roots of the characteristic equation (polynomial of the denominator of the transfer function of the system “control object electromagnetic-acoustic transducer”) on the complex plane . The transfer function of the studied system “control object electromagneticacoustic transducer” is an integral quantitative parameter characterizing the state of the equipment metal

Flat-Band Electronic Structure and Interlayer Spacing Influence in Rhombohedral Four-Layer Graphene

The stacking order of multilayer graphene significantly influences its electronic properties. The rhombohedral stacking sequence is predicted to introduce a flat band, which has high density of states and the enhanced Coulomb interaction between charge carriers, thus possibly resulting in superconductivity, fractional quantum Hall effect, and many other exotic phases of matter. In this work, we comprehensively study the effect of the stacking sequence and interlayer spacing on the electronic structure of four-layer graphene, which was grown on a high crystalline quality 3C-SiC(111) crystal. The number of graphene layers and coverage were determined by low energy electron microscopy. First-principles density functional theory calculations show distinctively different band structures for ABAB (Bernal), ABCA (rhombohedral), and ABCB (turbostratic) stacking sequences. By comparing with angle-resolved photoelectron spectroscopy data, we can verify the existence of a rhombohedral stacking sequence and a nearly dispersionless electronic band (flat band) near the Fermi level. Moreover, we find that the momentum width, bandgap, and curvature of the flat-band region can be tuned by the interlayer spacing, which plays an important role in superconductivity and many other exotic phases of matter

Comparative study of mass-spectrometric behavior of 2,6-diaryl-4-(oxo,oximino,amino)piperidines

The fragmentation of the investigated piperidine derivatives, which was confirmed by data from the high-resolution spectra, by the DADI spectra, and by the fragmentation of the deutero analogs, proceeds with cleavage of the piperidine ring and is due to the competitive distribution of the charge on the ring nitrogen atom and on the structural elements that contain functional groups and an aryl radical. The dependence of the mass spectra of 4-(oxo,oximino,amino)piperidines on the nature and position of the substituents in the ring, as well as on the character of the functional group in the 4 position of the ring, was investigated. © 1990 Plenum Publishing Corporation

Comparative study of mass-spectrometric behavior of 2,6-diaryl-4-(oxo,oximino,amino)piperidines

The fragmentation of the investigated piperidine derivatives, which was confirmed by data from the high-resolution spectra, by the DADI spectra, and by the fragmentation of the deutero analogs, proceeds with cleavage of the piperidine ring and is due to the competitive distribution of the charge on the ring nitrogen atom and on the structural elements that contain functional groups and an aryl radical. The dependence of the mass spectra of 4-(oxo,oximino,amino)piperidines on the nature and position of the substituents in the ring, as well as on the character of the functional group in the 4 position of the ring, was investigated. © 1990 Plenum Publishing Corporation