562 research outputs found
Analyzing flow anisotropies with excursion sets in relativistic heavy-ion collisions
We show that flow anisotropies in relativistic heavy-ion collisions can be
analyzed using a certain technique of shape analysis of excursion sets recently
proposed by us for CMBR fluctuations to investigate anisotropic expansion
history of the universe. The technique analyzes shapes (sizes) of patches above
(below) certain threshold value for transverse energy/particle number (the
excursion sets) as a function of the azimuthal angle and rapidity. Modeling
flow by imparting extra anisotropic momentum to the momentum distribution of
particles from HIJING, we compare the resulting distributions for excursion
sets at two different azimuthal angles. Angles with maximum difference in the
two distributions identify the event plane, and the magnitude of difference in
the two distributions relates to the magnitude of momentum anisotropy, i.e.
elliptic flow.Comment: 5 pages, 4 figure
Challenges in Recovery of Valuable and Hazardous Elements from Bulk Fly Ash and Options for Increasing Fly Ash Utilization
Beneficiation of fly ash should require for ensuring the removal of reactive elements to reduce the effect of hazardous impact on our atmosphere and can fill the demand for resources such as metals and rare earths. In this chapter, we concentrate to describe the responsible factors involve in fly ash beneficiation that has a great contribution to our environment. The purpose of the current study is to know the recovery of different minerals; maximum removal of the contaminant, reactivity and neutralization capacity of acid mine drainage (AMD) with fly ash and development of the cost‐effective method of disposal of fly ash are achieved. Different beneficiation techniques of fly ash and utilization of fly ash are explained
Effects of quarks on the formation and evolution of Z(3) walls and strings in relativistic heavy-ion collisions
We investigate the effects of explicit breaking of Z(3) symmetry due to the
presence of dynamical quarks on the formation and evolution of Z(3) walls and
associated QGP strings within Polyakov loop model. We carry out numerical
simulations of the first order quark-hadron phase transition via bubble
nucleation (which may be appropriate, for example, at finite baryon chemical
potential) in the context of relativistic heavy-ion collision experiments.
Using appropriate shifting of the order parameter in the Polyakov loop
effective potential, we calculate the bubble profiles using bounce technique,
for the true vacuum as well as for the metastable Z(3) vacua, and estimate the
associated nucleation probabilities. These different bubbles are then nucleated
and evolved and resulting formation and dynamics of Z(3) walls and QGP strings
is studied. We discuss various implications of the existence of these Z(3)
interfaces and the QGP strings, especially in view of the effects of the
explicit breaking of the Z(3) symmetry on the formation and dynamical evolution
of these objects.Comment: 17 pages, 9 figures, PDFLate
Metallic Glasses: A Revolution in Material Science
Metallic glasses represent one kind of advanced material, very popular in recent decades. These materials are very adaptable like plastics for their manufacturability in very complex shapes. TPF (Thermoplastic forming) based processes seem very good method to process them. These materials can compete with plastics but have metallic properties. They behave as magnetic materials with less hysteresis loss and less eddy current loss making them suitable for transformer and MEMS (Micro-Electromechanical System) applications. These materials exhibit good corrosion resistance, hardness and toughness. Based on the property and application, metallic glasses are good rivals to plastics, metals and ceramics. Chemical composition and kinetics of supercooling of these materials are the areas where young researchers can focus attention with a view to their improvement
Probing the anisotropic expansion history of the universe with cosmic microwave background
We propose a simple technique to detect any anisotropic expansion stage in
the history of the universe starting from the inflationary stage to the surface
of last scattering from the CMBR data. We use the property that any anisotropic
expansion in the universe would deform the shapes of the primordial density
perturbations and this deformation can be detected in a shape analysis of
superhorizon fluctuations in CMBR. Using this analysis we obtain the constraint
on any previous anisotropic expansion of the universe to be less than about
35%.Comment: 16 pages, 11 figures (color online
Wear: A Serious Problem in Industry
Wear is the damaging, gradual removal or deformation of material at solid surfaces. Causes of wear can be mechanical or chemical. The study of wear and related processes is known as tribology. Abrasive wear alone has been estimated to cost 1–4% of the gross national product of industrialized nations. The current chapter focuses on types of wear phenomena observed in the industries (such as abrasive wear, adhesive wear, fretting wear, fatigue wear, erosive wear and corrosive wear), their mechanisms, application of surface coating for the protection of the surface from the industrial wear, types of surface coatings, thermal spray coating, types of thermal spray coating and its application in industry to protect the surface from wear. The detail information about the wear phenomena will help the industries to minimize their maintenance cost of the parts
- …