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The purpose of this paper is concerned with the study of nonlinear ultrasonic waves in a magneto-flexo-thermo (MFT) elastic armchair single-walled carbon nanotube (ASWCNT) resting on polymer matrix.

A mathematical model is developed for the analytical study of nonlinear ultrasonic waves in a MFT elastic armchair single walled carbon nanotube rested on polymer matrix using Euler beam theory. The analytical formulation is developed based on Eringen’s nonlocal elasticity theory to account small scale effect. After developing the formal solution of the mathematical model consisting of partial differential equations, the frequency equations have been analysed numerically by using the nonlinear foundations supported by Winkler-Pasternak model. The solution is obtained by ultrasonic wave dispersion relations.

From the literature survey, it is evident that the analytical formulation of nonlinear ultrasonic waves in an MFT elastic ASWCNT embedded on polymer matrix is not discussed by any researchers. So, in this paper the analytical solutions of nonlinear ultrasonic waves in an MFT elastic ASWCNT embedded on polymer matrix are studied. Parametric studies is carried out to scrutinize the influence of the nonlocal scaling, magneto-electro-mechanical loadings, foundation parameters, various boundary condition and length on the dimensionless frequency of nanotube. It is noticed that the boundary conditions, nonlocal parameter and tube geometrical parameters have significant effects on dimensionless frequency of nanotubes.

This paper contributes the analytical model to find the solution of nonlinear ultrasonic waves in an MFT elastic ASWCNT embedded on polymer matrix. It is observed that the increase in the foundation constants raises the stiffness of the medium and the structure is able to attain higher frequency once the edge condition is C-C followed by S-S. Further, it is noticed that the natural frequency is arrived below 1% in both local and nonlocal boundary conditions in the presence of temperature coefficients. Also, it is found that the density and Poisson ratio variation affects the natural frequency with below 2%. The results presented in this study can provide mechanism for the study and design of the nano devices such as component of nano oscillators, micro wave absorbing, nano-electron technology and nano-electro--magneto-mechanical systems that make use of the wave propagation properties of ASWCNTs embedded on polymer matrix.

Purpose: This chapter outlines a cultural critique of the Gangsta as an exemplary figure to investigate the performance of social media identity. The main goal of the chapter is to illustrate some of the implications that social media have on the contemporary dramatization of the criminal, here framed as a collective techno-cultural process at the threshold between social stigma and branding. Despite using the term “Gangsta,” the author’s intent is not to “fix” this figure as an identity or a class of people, but rather to identify a broad cultural context that emerges from a glocalized hip-hop imaginary, stemming from gangsta rap and evolving alongside trap and drill.

Methodology/approach: The contribution is not intended as an empirical sociological study, but a critical cultural exploration of convergent media that bring together a glocalized gang culture and everyday social media interactions. In the second section, the author outlines his theoretical framework by identifying a point of convergence between recent studies of Instagram celebrities and criminological takes on the selective nature of gang identity. The author also explores the relationship between the “dissing,” a cultural form that is very relevant to the more aggressive sub-genres of rap, and the practice of tagging, a key affordance of social media platforms. In so doing, the author frames social media tagging as a form of identity labeling.

Findings: In light of the theory previously outlined, the author explains how tagging is used alternately to enforce social stigma and engage in recursive branding. The final section examines the aforementioned forms of tagging more in detail, in relation to specific media ecologies of YouTube videos that feature compilations of Instagram Stories originally posted by emerging Italian rappers.

Research limitations: Although it is aimed at offering an interdisciplinary contribution, this chapter adopts an admittedly media-focused perspective. Rather than producing more evidence about the use of social media by gangs, the author comments on existing sociological insight in relation to the affordances and esthetics of social media ecologies, re-problematizing certain forms of online interaction.

Originality/value: By focusing on the commonplace practice of tagging in relation to the figure of the Gangsta, the author emphasizes how online labeling practices can be more fraught that they appear, emphasizing the need for further critical reflections on the stereotyping potential of social media branding practices.

This study aims to provide control of liquids, especially against water-based ink on the paper and paperboard surface with natural substances, in also practical and greenway.

The paper surface was treated with natural rosin and its derivatives to obtain a hydrophobic effect and to improve printing properties. The oleoresin samples collected from Pinus nigra Arnold and Pinus pinaster Aiton trees in the controlled area and turpentine content removed was by hydrodistillation. The gum rosin (GR), fortified 10% with maleic anhydride (MGR) and esterified with 10% pentaerythritol (PMGR) samples solved in a simply alcohol and sprayed the base paper surface directly with a spray gun. Base paper samples were paperboard, bleached paper and test liner paper. Then, flexo printing was applied and printability properties were measured.

The treatment weights of these paper samples were 1.8 ± 0.5, 1.3 ± 0.5 and 0.7 ± 0.2 g/m², respectively, compared to the base paper. Greater Cobb60 results were obtained from modified rosin samples than unmodified gum rosin-sized paperboards and the PMGR surface treatment reduces Cobb60 values by 20% and MGR treatment reduces 15% comparing to the base sheet. Then, the printing procedure was applied to the surface of the treated materials using a flexo printing system. As a result of the treatment better print density, chroma and print lightness value consumed a less hydrophobic agent and controlling water-based flexo ink on the base paper surface.

The unique aspect of this work was improving the hydrophobicity of the paper surfaces was achieved by spraying with natural rosin and derivatives.

A new series of printing inks that satisfy non‐absorbent substrates, namely, metals and metal foils has been formulated. The suggested ink formulations are well adapted for the Lithographic and Flexographic Printing Processes. The inks are subjected to different testings and controllings to fulfill the requirements of printers in the graphic trade.

Environmental, economic and market pressures have led to a dramatic increase in the production of recycled paper fibre in recent years and the growing demand for higher quality grades is now focusing attention on the recycling of office wastes. Although the role of chemistry in the recycling process for paper is well established, the introduction of newer inks and adhesives into the recycling chain has added to the existing problems of “getting the chemistry right”. This article examines the impact on the deinking of secondary paper fibre resulting from evolving ink technologies, catalysed by developments in the printing processes.