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This study aims to investigate the synergistic friction reduction and antiwear effects of lyophilized graphene loading nano-copper (RGO/Cu) as lubricating oil additives, compared with graphene.

The friction performance of freeze-drying graphene (RGO) and RGO/Cu particles was investigated at different addition concentrations and under different conditions.

Graphene plays a synergistic friction reduction and antiwear effect because of its large specific surface area, surface folds and loading capacity on the nanoparticles. The results showed that the average friction coefficients of RGO and RGO/Cu particles were 22.9% and 6.1% lower than that of base oil and RGO oil, respectively. In addition, the widths of wear scars were 62.3% and 55.3% lower than those of RGO/Cu particles, respectively.

The RGO single agent is suitable for medium-load and high-speed conditions, while the RGO/Cu particles can perform better in the conditions of heavy load and high speed.

The purpose of this paper is to investigate the chemical, optical and photovoltaic properties of titanium dioxide/reduced graphene oxide (TiO₂/rGO) photoanodes immersed in natural Roselle and synthetic (N719) dyes for dye-sensitized solar cell (DSSC) application.

TiO₂ mixed with rGO were doctor-bladed on fluorine doped tin oxide (FTO) glass substrate. The chemical and optical properties of TiO₂/rGO photoanodes immersed in Roselle and N719 dyes were characterized using Fourier-transformed infrared (FTIR) and ultraviolet–visible (UV–vis) spectroscopies, respectively. The DSSC’s photovoltaic performances were tested using Visiontec Solar I-V tester at standard illumination of AM1.5 and irradiance level of 100 mW/cm².

The presence of anthocyanin dye from Roselle flower was detected at 604 nm and 718 nm. TiO₂/rGO+Roselle dye sample revealed the smallest energy gap of 0.17 eV for ease of electron movement from valence band to conduction band. The TiO₂/rGO-based DSSC fabricated with Roselle dye had a power conversion efficiency, ƞ of 0.743 per cent higher than TiO₂/rGO photoanode sensitized with N719 dye (0.334 per cent). The obtained J-V curves were analyzed by a single-diode model of Lambert W-function and manual optimization to determine the internal electrical parameters of the DSSC. The average and uncertainty values of J_sc and ƞ were evaluated at different R_sh range of 1362 Ω to 32 k Ω.

R_s values were kept constant during optimization work.

New ideality factor of TiO₂/rGO-based DSSC was re-determined around 0.9995.

This paper aims to report the tribological behavior of Ag nanoparticles/reduced graphene oxide nanocomposites (Ag/RGO NCs) and Ag nanoparticles (Ag NPs) as a green additive in oil with different concentration and under different friction conditions.

The Ag/RGO NCs and Ag NPs were both synthesized in a chemical reduction method. The diameter of silver nanoparticles implanted between RGO sheets was about 25 nm and that of silver sol was 70 nm. The morphology and structure of Ag/RGO NC were characterized by TEM, XRD and FTIR. The tribological properties of Ag/RGO NCs and Ag NPs as lubricant oil additive were evaluated by measuring the friction coefficients and wear of the surface in different condition which were tested on UMT-II.

The results indicated that both the additives improved the friction-reduced and anti-wear properties of paraffin oil, and Ag/RGO NCs has better tribological performance than Ag NPs. The excellent tribological properties were attributed to the special structure of Ag/RGO NC and the formation of tribofilm reducing the friction and wear on the shearing surfaces.

It is relatively difficult to observe the morphology of the lubricant film formed on the friction surface and to analyze the chemical composition at different depths of the lubricant film.

It is the first time for Ag/RGO NCs to be applied to improve the friction-reduced and anti-wear properties of lubricant oil as additive.

Design, fabricate and evaluate all-solid-state wearable sensor systems that can monitor ion concentrations in human sweat to provide real time health analysis and disease diagnosis capabilities.

A human health monitoring system includes disposable customized flexible electrode array and a compact signal transmission-processing electronic unit.

Patterned rGO (reduced-graphene oxide) layers can replace traditional metal electrodes for the fabrication of free-standing all solid film sensors to provide improved flexibility, sensitivity, selectivity, and stability in ion concentration monitoring. Electrochemical measurements show the open circuit potential of current selective electrodes exhibit near Nernst responses versus Na+ and K+ ion concentration in sweat. These signals show great stability during a typical measurement period of 3 weeks. Sensor performances evaluated through real time measurements on human subjects show strong correlations between subject activity and sweating levels, confirming high degree of robustness, sensitivity, reliability and practicality of current sensor systems.

In improving flexibility, stability and interfacial coherency of chemical sensor arrays, rGO films have been the developed as a high-performance alternative to conventional electrode with significant cost and processing complexity reduction. rGO supported solid state electrode arrays have been found to have linear potential response versus ion concentration, suitable for electrochemical sensing applications. Current sweat sensor system has a high degree of integration, including electrode arrays, signal processing circuits, and data visualization interfaces.

Nylon 6 filaments have weak light and heat resistance in terms of stability, which restrict its application in engineering field. The purpose of this paper is to prepare a new photo-stabilization functional nanocomposite inks by using graphene nanosheet as UV light-resisting functional materials incorporated with polyurethane.

Sunlight-resisting functional nylon filaments were produced by the continuous solution dip coating technology, through which the functional inks was coated on the surface of nylon 6 filament. The surface morphology of the coated filaments was characterized by scanning electron microscopy and the graphene/polyurethane nanocomposite inks as the coating agent was confirmed and well dispersed on the fiber’s surface.

Under UV exposure, the strength loss rate of the graphene-modified nylon filaments was less than 50 percent, while that of the control nylon filament was over 85 percent, which indicated that graphene remarkably enhanced the light-resistant property of nylon. Besides, graphene/polyurethane-coated Nylon 6 filaments exhibited reasonable electrical properties and the electrical conductivity could reach 10–4 S/cm.

Graphene inks was first proposed as the UV photo-stabilization in this paper.

The purpose of this paper is to investigate the tribological properties of carbonized polydopamine/reduced graphene oxide (CPDA/rGO) composite coatings.

CPDA/rGO composite coatings were prepared using the spray technique and subsequent pyrolysis under argon. The transmission electron microscopy, field-emission scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy revealed the conversion of PDA and GO into CPDA and rGO, respectively.

The results of tribological investigations show that the CPDA/rGO composite coatings with heat treatment at 300°C possess much better friction-reduction and anti-wear properties.

The worn surfaces of the PDA/GO composite films after heat treatment at 300°C were much smoother than that of the copper substrate. The tribofilms containing C, N, O and Cu played an important role on reducing friction and increasing wear resistance.

Based on DNase I and reduced graphene oxide (rGO)-magnetic silicon microspheres (MNPS), a highly sensitive and selective fluorescent probe for the detection of PD-L1 was developed.

Here °C we present a feasibility of biosensor to detection of PD-L1 in lung tumors plasma. In the absence of PD-L1°C the PD-L1 aptamer is absorbed on the surface of graphene oxide modified magnetic nanoparticles °8rGO-MNPS°9 and leading to effective fluorescence quenching. Upon adding PD-L1°C the aptamer sequences could be specifically recognized by PD-L1 and the aptamer/PD-L1 complex is formed°C resulting in the recovery of quenched fluorescence.

This sensor can detect PD-L1 with a linear range from 100 pg mL⁻¹ to 100 ng mL⁻¹, and a detection limit of 10 pg•m⁻¹ was achieved.

This method provides an easy and sensitive method for the detection of PD-L1 and will be beneficial to the early diagnosis and prognosis of tumors.

Nanotechnology has been able to bind to a wide range of functional textiles in recently. This paper aims to modify graphene oxide (GO) by grafting dimethyl phosphite and perfluorohexyl iodine. It was applied to cotton to obtain a flame-retardant, water-repellent and ultraviolet-resistant multifunctional fabric.

The GO-multi was synthesized by grafted dimethyl phosphite and perfluorohexyl chain and applied to cotton by the dipping-drying method. The surface chemistry of functionalized GO was characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The thermal stability of the fabric was characterized by thermogravimetric analysis (TGA). The combustion properties were evaluated using a microscale combustion calorimeter, match test and TGA. Hydrophobicity of film and fabric surface was characterized by static contact angle, and the UV resistance of the fabric was represented by the ultroviolet procetion factor (UPF) value.

Dimethyl phosphite and perfluorohexyl chains were grafted on the surface of GO successively. In the match test, the GO-multi/cotton kept the original outline of the fabric. According to the micro-scale combustion calorimetry (MCC) data, the value of PHRR and THR of GO-multi/cotton was about 45 per cent lower than that of untreated cotton fabric. It was found from the field-emission scanning electron microscopy (SEM) pictures that the residue of GO-multi/ cotton burned by the match method was more compact and the graphene lamellar structure remained more complete. The hydrophobic effect of GO-multi/cotton was improved compared to untreated cotton, but not better than the fabric treated by the perfluorohexyl chain-grafted GO. The UPF value of GO-multi/cotton reached 253, which indicated that the anti-ultraviolet performance of GO-multi was greatly improved after it was deposited on the cotton fabric.

Although the hydrophobic effect was much higher than that of untreated cotton fabric, its hydrophobic effect was not satisfied, which may be due to the fact that the content of F element content was low. So, it is still needed to explore the modifying method to increase the functional component amount on the GO nanosheet.

This modifying method can be used in any of multifunctional textile preparation process. The hydrophobic and flame-retardant cotton fabric revealed a sample for use in outdoor sports such as clothes and tents.

To meet the needs of multifunctional cotton fabrics, the modification of GO with dimethyl phosphite and perfluorohexyl iodine has not been reported. The modified fabric has flame-retardant, UV-resistant and hydrophobic properties.

Graphene, which has abundant availability in nature, is currently under research for its functional applications in the field of textiles. The sp² Hybridized 1-atom-thick planar sheet has been under consideration for its unique electrical, mechanical and thermal properties, but there exists a void for aggregated data on the findings of other co-functional properties attained by the material using graphene oxide (GO) finish. This paper aims to define the techniques of extraction of GO, method of its application on textile material followed by detailed evaluation of the differential functional properties achieved.

The methodology used to explain the multiple functionalities of GO finish have been carried out by starting with the chemistry of graphene and the isolation of GO from graphite, followed by the techniques for its application on the textile along with the study on the induced functional properties that may aid to increase its potential applications.

It has been observed that with the aid of optimization of GO finish, the finish in lieu with the conductive potentialities may further provide with many essential properties such as hydrophobicity, ultraviolet protection and antibacterial property.

The field of research on GO finish is naive and except few properties, many functionalities are still unexplored that may enable its smooth production, handling and expanding its area of application. The agglomeration of scattered findings on the achievable functional properties of GO on various textiles has been achieved in this paper.

Purpose – This chapter examines how those who study issues related to radicalization and counter-radicalization have recently drawn from the experiences of former extremists to inform our understanding of complex issues in terrorism and extremism studies.

Approach – The authors synthesize the empirical research on radicalization and counter-radicalization that incorporates formers in the research designs. In doing so, the authors trace these research trends as they unfold throughout the life-course: (1) extremist precursors; (2) radicalization toward extremist violence; (3) leaving violent extremism; and (4) combating violent extremism.

Findings – While formers have informed our understanding of an array of issues related to radicalization and counter-radicalization, empirical research in this space is in its infancy and requires ongoing analyses.

Value – This chapter provides researchers, practitioners, and policymakers with an in-depth account of how formers have informed radicalization and counter-radicalization research in recent years as well as an overview of some of the key gaps in the empirical literature.