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Graphene, a two-dimensional single layered carbon atoms crystal lattice has grabbed much attention due to its unique electronic, surface, mechanical and optoelectronic characteristics. Owing to its unique structure and properties, graphene has opened new opportunities for the future systems and devices, which has led to increase its demand in numerous applications. However, scaling up its production is still a challenging job. Although there is a huge body of literature on the graphene synthesis using various techniques but eco-friendly and cost–effective processes for mass scale production are still needed. In order to conceptualize and develop the processes fulfilling the growing concerns, it is important to overview the existing literature. The current review summarizes the production of graphene using several approaches as well as the potential of various waste materials as graphene precursors. The methods used for graphene synthesis have been categorized into top down techniques such as chemical exfoliation, mechanical exfoliation and chemical fabrication processes, and bottom up techniques including pyrolysis, plasma synthesis, epitaxial growth and chemical vapor deposition (CVD) processes. Conversely, several limitations are considerate for an individual procedure such as toxicity of chemicals, high-cost, time consumption or inadequate quality of the product. Furthermore, mass production of graphene derivatives under low-cost can also be considered by utilizing a variety of wastes precursors such as plastic and batteries waste, newspaper, biomass, chitosan, coal, insects waste etc. This review designates the current advances in wastes-derived graphene synthesis to relief synthetic difficulties as well as predicts the future development in this area.

With the help of current neutrino oscillation data, we illustrate the three-dimensional (3D) profiles of all the six distinct effective Majorana neutrino masses $|\langle m\rangle^{}_{\alpha \beta}|$ (for $\alpha, \beta = e, \mu, \tau$) with respect to the unknown neutrino mass scale and effective Majorana CP phases. Some salient features of $|\langle m\rangle^{}_{\alpha \beta}|$ and their phenomenological implications are discussed in both the normal and inverted neutrino mass ordering cases., Comment: 28 pages, 15 figures. More discussions and references added. Accepted for publication in Nucl. Phys. B

The Gatto Sartori Tonin (GST) relation which establishes the Cabibbo angle in terms of the quark mass ratio: $\theta_{C}=\sqrt{m_d/m_s}$, is instituted as $\theta_{13}=\sqrt{m_1/m_3}$ to a Bi-large motivated lepton mixing framework that relies on the unification of mixing parameters: $\theta_{13}=\theta_{C}$ and $\theta_{12}=\theta_{23}$. This modification in addition to ruling out the possibility of vanishing $\theta_{13}$, advocates for a nonzero lowest neutrino mass and underlines the normal ordering of the neutrino masses. The framework is further enhanced by the inclusion of a charged lepton diagonalizing matrix $U_{lL}$ with $ (\theta_{12}^l \sim \theta_C, \delta=0)$. The model being architected at the Grand unification theory (GUT) scale is further run down upto the $Z$ boson scale to understand the universality of the GST relation and the Cabibbo angle., Comment: 14 pages, 10 figures, 2 tables

It has been widely known that bino-like dark matter in the supersymmetric (SUSY) theories in general suffers from over-production. The situation can be drastically improved if gluinos have a mass slightly heavier than the bino dark matter as they reduce the dark matter abundance through coannihilation. In this work, we consider such a bino-gluino coannihilation scenario in high-scale SUSY models, which can be actually realized when the squark-mass scale is less than 100-1000 TeV. We study the prospects for exploring this bino-gluino coannihilation scenario at the LHC. We show that the searches for long-lived colored particles with displaced vertices offer a strong tool to test this scenario in collider experiments., 15 pages, 4 figures

The absolute mass scale of neutrinos remains an open question subject to experimental investigation from both particle physics and cosmology. Over the next decade, a number of experiments from both disciplines will attempt to probe the mass scale further to the very limits of the predictions from oscillation results. This paper provides a broad overview of the experimental program in neutrino mass scale measurements, with a particular focus on direct experimental probes due to come online over the next decade., United States. Dept. of Energy (Contract DE-FG02-06ER-41420)

(1) ( kμk μ )2 +mkμkζνζ ν −m2(ζμkμ)2 = 0, where kμ ≡ (ω/c, k) is the wave number four-vector, m the CS mass scale, and ζμ = ζμ(x) the spacelike CS “four-vector”. The geometrical-optics approximation of this theory was considered and a modified wave number four-vector k was introduced. It was claimed, in Section 3 of Ref. [1], that this k obeys a geodesic-like equation. However, we have now realized that this statement is incorrect. Instead of Eq. (3.9) of Ref. [1], the complete equation for k reads

Polymer matrix composite products are manufactured on a mass scale that is increasing each year, along with consumer interest and government legislation driving the pressure for them to be recycled. A major factor determining the route for recycling of a polymer matrix composite is whether the matrix is a thermoplastic or a thermosetting plastic (thermoset); unlike thermosets, thermoplastics can be melted and therefore lend themselves more readily to recycling by being mechanically broken down for remoulding. Techniques for recycling thermoset and thermoplastic matrix composites are discussed including mechanical breakdown, thermal recycling as well as chemical recycling with available information on the related quality and where known, the durability of the recycled materials.

The one-loop effective potential of a locally supersymmetric grand unified theory is obtained. It is shown that local supersymmetry does not break perturbatively with loop corrections. When tree level breaking of supersymmetry is introduced at a mass scale mS ∼ 1TeV, quantum corrections are shown to protect this scale. A mechanism for generation of mS in terms of the GUT mass M and the Planck mass is discussed.

Harnessing of renewable sources of energy promises great economic upliftment of developing countries. Arguing that this can materialise only if such sources are adopted for mass consumption, attention is drawn to the danger of this move getting frustrated through severe constraints of the lack of the required materials and manpower. The origin of such constraints, are discussed keeping in view the varieties, grades and scales of requirement. Stressing that a programme for mass scale use of renewable sources without measures for avoiding these constraints, would be futile, a 3-tier course of action is advocated, viz., (i) an in-depth survey of the nature and magnitude of these constraints in typical countries, (ii) identification of measures required for circumventing these and (iii) recasting of the National Development Plan for a natural integration of these with the same.

Massenspektrometrische Untersuchungen schnell verlaufender Vorgange erfordern eine moglichst kurze Durchlaufzeit des gesamten Massenspektrums oder eines besonders interessierenden Teilspektrums. Die Durchlaufzeit wird in erster Linie durch die Zeitkonstante des Verstarkers bestimmt. Um sie voll auszunutzen, ist es notig, alle Linien mit derselben Breite zu schreiben, das bedeutet beim Omegatron, dass dfldt konstant sein muss. Mit dieser Bedingung wird jedoch die Massenskala des Omegatrons ausserst ungunstig, weil grosse Lucken im Bereich kleiner Massen entstehen, in denen keine Linien liegen. Deshalb wurde ein Oszillator mit konstanter zeitlicher Frequenzanderung gebaut, der die Bereiche uberspringt, die den Lucken entsprechen. Mit einem extrem schnellen Verstarker besonderer Bauart lasst sich so das Spektrum von Masse 1 bis Masse 200 bei einem Totaldruck von etwa 10× 8 Torr in einer Sekunde schreiben. Hierdurch wurde es moglich, schnellveranderliche Desorptionsvorgange qualitativ zu untersuchen. For carrying out mass-spectrometric studies of fast processes it is essential that the whole mass spectrum or an especially interesting part of the spectrum can be recorded in as short a time as possible. The recording time is chiefly determined by the time constant of the amplifier. For it to be fully utilized, it is necessary to record all lines having the same width, which means that in the case of the Omegatron dfldt must be constant. With this condition, however, the mass scale of the Omegatron becomes extremely unfavourable because large gaps appear in the range of small masses, in which there are no lines. Therefore, an oscillator has been constructed with a constant frequency change per unit time, which skips the ranges that correspond to the gaps. By using an extremely rapid amplifier of special design, the spectrum from mass 1 to mass 200 can be recorded, at a total pressure of about 10× 8 torr in one second. As a result, it has become possible for qualitative studies to be made of quickly changing desorption processes. Les etudes de processus rapides par spectrometrie de masse exigent que le spectre de masse, ou une partie du spectre specialement interessante soit enregistre dans le temps le plus court possible. Le temps d'enregistrement est principalement determine par la constante de temps de l'amplificateur. Pour utiliser entierement celle-ci, il faut enregistrer toutes les raies avec la meme largeur, ce qui signifie que, dans le cas de l'Omegatron, dfldt doit etre constant. Sous cette condition toutefois, l'echelle de masse de l'Omegatron devient extremement defavorable parce que, dans le domaine des faibles masses, apparaissent de grandes lacunes dans lesquelles il n'y a pas de raies. C'est pourquoi on a construit un oscillateur dont la frequence varie d'une maniere constante avec le temps et qui saute au-dessus des domaines partiels correspondant aux lacunes. En employant un amplificateur extremement rapide d'un type special, on peut enregistrer en une seconde le spectre de la masse 1 a la masse 200, a une pression totale de 10× 8 Torr environ. ll en resulte qu'on a pu etudier qualitativement des processus de desorption variant rapidement.