Reactor design and energy concepts for a plasma process of acetylene black production

Acetylene black can be produced from methane decomposition in a plasma reactor. Different types of plasma reactor are designed for this purpose and a parametric analysis of the system is made. Carbon yield in the reactor seems to be dependent on methane flow rate and plasma power. The results obtained from various types of material analysis of the product obtained show that in some conditions carbon produced under plasma has qualities similar to acetylene black obtained by classical processes.     

Amorphous/crystalline silicon heterojunction solar cells with black silicon texture

Excellent passivation of black silicon surfaces by thin amorphous silicon layers deposited with plasma enhanced chemical vapor deposition is demonstrated. Minority charge carrier lifetimes of 1.3 milliseconds, enabling an implied open‐circuit voltage of 714 mV, were achieved. The influence of amorphous silicon parasitic epitaxial growth and thickness, as well as of the texture depth is investigated. Furthermore, quantum efficiency gains for wavelengths above 600 nm, as compared to random textured solar cells, are demonstrated in 17.2% efficient amorphous–crystalline silicon heterojunction solar cells with black silicon texture. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

Thermodynamics of noncommutative geometry inspired black holes based on Maxwell-Boltzmann smeared mass distribution

In order to further explore the effects of non-Gaussian smeared mass distribution on the thermodynamical properties of noncommutative black holes, we consider noncommutative black holes based on Maxwell-Boltzmann smeared mass distribution in (2+1)-dimensional spacetime. The thermodynamical properties of the black holes are investigated, including Hawking temperature, heat capacity, entropy and free energy. We find that multiple black holes with the same temperature do not exist, while there exists a possible decay of the noncommutative black hole based on Maxwell-Boltzmann smeared mass distribution into the rotating (commutative) BTZ black hole.     

Patterning of oxide-hardened gold black by photolithography and metal lift-off

A method to pattern infrared-absorbing gold black by conventional photolithography and lift-off is described. A photo-resist pattern is developed on a substrate by standard photolithography. Gold black is deposited over the whole by thermal evaporation in an inert gas at ∼1 Torr. SiO₂ is then deposited as a protection layer by electron beam evaporation. Lift-off proceeds by dissolving the photoresist in acetone. The resulting sub-millimeter size gold black patterns that remain on the substrate retain high infrared absorption out to ∼5 μm wavelength and exhibit good mechanical stability. This technique allows selective application of gold black coatings to the pixels of thermal infrared imaging array detectors.     

Rotating Charged Hairy Black Hole in(2+1) Dimensions and Particle Acceleration

In this paper, we construct rotating charged hairy black hole in(2+1) dimensions for infinitesimal black hole charge and rotation parameters. Then we consider this black hole as particle accelerator and calculate the centerof-mass energy of two colliding test particles near the rotating charged hairy black hole in(2+1) dimensions. As we expected, the center-of-mass energy has infinite value.     

On Rockafellar’s theorem using proximal point algorithm involving -maximal monotonicity framework

On the basis of the general framework of H-maximal monotonicity (also referred to as H-monotonicity in the literature), a generalization to Rockafellar’s theorem in the context of solving a general inclusion problem involving a set-valued maximal monotone operator using the proximal point algorithm in a Hilbert space setting is explored. As a matter of fact, this class of inclusion problems reduces to a class of variational inequalities as well as to a class of complementarity problems. This proximal point algorithm turns out to be of interest in the sense that it plays a significant role in certain computational methods of multipliers in nonlinear programming. The notion of H-maximal monotonicity generalizes the general theory of set-valued maximal monotone mappings to a new level. Furthermore, some results on general firm nonexpansiveness and resolvent mapping corresponding to H-monotonicity are also given.     

Solvability of the -Laplacian with nonlocal boundary conditions

Rather mild sufficient conditions are provided for the existence of positive solutions of a boundary value problem of the form

which unify several cases discussed in the literature. In order to formulate these conditions one needs to know only properties of the homeomorphism and have information about the level of growth of the response operator F. No metric information concerning the linear operators L₀,L₁ in the boundary conditions is used, except that they are positive and continuous and such that L_j(1)<1 j{0,1}.     

Modified regular black holes with time delay and 1-loop quantum correction

We develop the regular black hole solutions by incorporating the 1-loop quantum correction to the Newton potential and a time delay between an observer at the regular center and one at infinity. We define the maximal time delay between the center and the infinity by scanning the mass of black holes such that the sub-Planckian feature of the Kretschmann scalar curvature is preserved during the process of evaporation. We also compare the distinct behavior of the Kretschmann curvature for black holes with asymptotically Minkowski cores and those with asymptotically de-Sitter cores, including Bardeen and Hayward black holes. We expect that such regular black holes may provide more information about the construction of effective metrics for Planck stars.     

Effect of dark energy models on the energy content of charged and rotating black holes

The energy content of the charged-Kerr(CK)spacetime surrounded by dark energy(DE)is investigated using approximate Lie symmetry methods for the differential equations.For this,we consider three different DE scenarios:cosmological constant with an equation of state parameter$ω_q=-2/3,quintessence DE with an equation of state parameterω_c=-1,and a frustrated network of cosmic strings with an equation of state parameterω_n=-1/3.To study the gravitational energy of the CK black hole surrounded by the DE,we explore the symmetries of the 2nd-order perturbed geodesic equations.It is noticed,for all the values ofω,the exact symmetries are recovered as 2nd-order approximate trivial symmetries.These trivial approximate symmetries give the rescaling of arc length parameter s in this spacetime which indicates that the energy in the underlying spacetime has to be rescaled by a factor that depends on the black hole parameters and the DE parameter.This rescaling factor is compared with the factor of the CK spacetime found in[Hussain et al.Gen.Relativ.Gravit.(2009)]and the effects of the DE on it are discussed.It is observed that for all the three values of the equation of state parameterω,the effect of DE results in decreased energy content of the black hole spacetime,regardless of values of the charge Q,spin a and the DE parameterα.This reduction in the energy content due to the involvement of the DE favours the idea of mass reduction of black holes by accretion of DE given by[Babichev et al.Phys.Rev.Lett.(2004)].