Investigation of the Chemical Composition of Films Obtained by Electric Arc Spraying of Graphite and Titanium from Two Sources

A promising material for cold cathodes creation are carbon films with both acceptable emission properties and satisfactory adhesion to the substrate. It is known that inclusions of metallic elements (chromium, titanium, etc.) improve the adhesion of the carbon film to the substrate. One of the methods for producing coatings based on carbon and titanium is electric arc spraying of a Ti/C composite cathode in an argon atmosphere. The disadvantage of this method is the presence in the total plasma flow of carbon microparticles, which are sources of structural defects in the growing film. Magnetic separation of carbon plasma solves the above problem. In this work, composite metal-carbon films were obtained by simultaneous electric arc spraying of graphite in a magnetic field and of titanium from two evaporators. The composition of the films was studied by Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS). It has been established that the samples obtained are composite films consisting of graphite nanoparticles, Ti14C13 nanoclusters or Ti8C12, titanium oxides, and titanium carbide TiCxN1–x compounds.

Mechanical and Microscopic Properties of Graphite/Laterite Nanocomposites

The effectiveness and improvement mechanism of graphite nanoparticles (GN) in strength properties and microstructure characteristics of regional laterite were analysed in this study. Dry density was also taken into consideration, and the effects of graphite nanoparticle (GN) content and dry density were mainly addressed. Triaxial tests, consolidation tests, and penetration tests were used to analyse the effectiveness of different dry densities and graphite nanoparticle mass ratios on the properties of laterite; microscopic methods such as scanning electron microscopy (SEM) tests were used to analyse the improvement mechanism. The results show that the increase in dry density can make the laterite more compact. The large specific surface area and nanoeffects of the graphite nanoparticles (GN) induce the attraction between soil particles after mixing, both of which make the laterite’s shear strength; compression index and impermeability have been enhanced to varying degrees. The microscopic tests showed that, as the content of graphite nanoparticles (GN) continues to increase, when it exceeds 1.0%, the attraction between soil particles increases and coarse particles are formed, which leads to the increase of the pores of the soil. In addition, the graphite nanoparticles have a certain degree of lubricity, a high amount of graphite nanoparticles enters the laterite soil layer, increasing the distance and gap between the layers, making it easy to separate the coarse particles from the coarse particles, and the strength increase is reduced. However, it is still stronger than that of the plain laterite.

Laser Intensity Profile Based Terahertz Field Enhancement from a Mixture of Nano-Particles Embedded in a Gas

Nano-particle embedded system plays an importance in developing of future terahertz (THz) radiation source for real-world applications. The laser interactions with nanoparticle embedded system can produce a wide range of THz radiation due to plasma oscillations excitation. We investigate THz field generation from the laser-beat wave interaction with a mixture of spherical and cylindrical graphite nanoparticles (NPs) in argon gas. Different laser intensity distributions such as Gaussian, cosh-Gaussian, flat-top and ring shape laser pulses have been studied in this work. The relevant plasmon resonance conditions with appropriate symmetry of spherical nanoparticles (SNPs) and cylindrical nanoparticles (CNPs) are discussed. THz field is enhanced upto the order of when the laser intensity redistributes along the polarization direction for a ring shape field envelope.

Nanomaterials: An alternative approach for Prevention and diagnosis of the emerging COVID-19 (Preprint)

UNSTRUCTURED Coronavirus has evolved from the severe acute respiratory syndrome (SARS-CoV-2) family known to create an illness in 2019 named as COVID-19 illness which is pervasive as the greatest menace to mankind. This pandemic is not only a health crisis but a socio-economic crisis that is hitting the world. Because it is causing stress in the nations it affects, and because it has the potential to have severe economic, political and social consequences with long-term consequences. Government bodies, researchers and scientists are working day and night to come up with ways, treatments and vaccines to combat COVID-19. Recent studies have led the researchers to pay attention and make good use of nanomaterials to help them fight against the global pandemic of COVID-19. Graphene and the graphene related materials have fascinating properties like antiviral, optical, antimicrobial, physiochemical, and many other extraordinary properties that make them a contender for the formation and design of high-tech devices and devices that can be used to combat infection during the COVD-19 pandemic and for other future uses. Due to its highly helpful qualities in the eradication of viruses, graphene and its composites can be utilized in the creation of diagnostic tests as well as in therapies. As a result, using graphite nanoparticles in biomedical applications is a viable strategy for limiting viral pandemics at the local, national, and international levels. Graphical representation of this article is given in Figure 1

Controlling Nanostructure in Inkjet Printed Organic Transistors for Pressure Sensing Applications

This work reports the development of a highly sensitive pressure detector prepared by inkjet printing of electroactive organic semiconducting materials. The pressure sensing is achieved by incorporating a quantum tunnelling composite material composed of graphite nanoparticles in a rubber matrix into the multilayer nanostructure of a printed organic thin film transistor. This printed device was able to convert shock wave inputs rapidly and reproducibly into an inherently amplified electronic output signal. Variation of the organic ink material, solvents, and printing speeds were shown to modulate the multilayer nanostructure of the organic semiconducting and dielectric layers, enabling tuneable optimisation of the transistor response. The optimised printed device exhibits rapid switching from a non-conductive to a conductive state upon application of low pressures whilst operating at very low source-drain voltages (0–5 V), a feature that is often required in applications sensitive to stray electromagnetic signals but is not provided by conventional inorganic transistors and switches. The printed sensor also operates without the need for any gate voltage bias, further reducing the electronics required for operation. The printable low-voltage sensing and signalling system offers a route to simple low-cost assemblies for secure detection of stimuli in highly energetic systems including combustible or chemically sensitive materials.

Preparation and Performance Analysis of Graphite Nanoparticle in Domestic Refrigerator

This article examines experimentally the performance of domestic refrigerators with isobutene (R600a) and graphite nano-lubricants as working fluids. Graphene has an extremely thin layer structure that fills the friction surfaces and reduces friction losses quickly. However, there is a lower coefficient of friction (COF) and higher thermal conductivity of nano-fluids generated using graphite in the base fluid. The graphite nanoparticles modified in the surface are verified to continuously suspend for a long period of time in the form of clusters. The refrigeration test examined the application of the graphite nano-lubricants in the domestic refrigerator with a volume concentration of 0.1%, 0.3%, and 0.5%. The findings show that nano-refrigerants in the refrigeration system work safely and normally. And also compressor and refrigerator output have been analyzed. Moreover, refrigerator energy usage decreased by 15.26%, 17.10%, and 21.16% with graphite nano-lubricant as a concentration of 0.1%, 0.3% and 0.5%, respectively.

XRD and Microscopic Images for Synthesis Graphite Nanoparticles by Oxidation Method

Graphite nanoparticles were successfully synthesized using mixture of H2O2/NH4OH with three steps of oxidation. The process of oxidations were analysis by XRD and optics microscopic images which shows clear change in particle size of graphite after every steps of oxidation. The method depend on treatments the graphite with H2O2 in two steps than complete the last steps by reacting with H2O2/NH4OH with equal quantities. The process did not reduces the several sheets for graphite but dispersion the aggregates of multi-sheets carbon when removed the Van Der Waals forces through the oxidation process.

Improving the Dispersion Behavior of Organic Components in Water-Based Electrode Dispersions for Inkjet Printing Processes

Water-based processing of electrodes is associated with an enhanced environmental footprint for lithium-ion battery (LIB) production in conjunction with reduced costs. This trend is accompanied by an increasing demand for electrode dispersion processing in inkjet printing. However, most of the dispersion components show a low inherent dispersibility with poor stability in aqueous formulations. This is particularly important when it comes to qualifying electrode dispersions for use in inkjet printing, since the effect of agglomeration and sedimentation effects must be effectively prevented. Therefore, additives are needed to improve the dispersive behavior. This paper analyzes the suitability of dispersants for organic electrode components, in particular graphite and carbon black. An empirical approach was devised on the basis of comprehensive theoretical considerations. Empirical investigations revealed that the utilization of polyvinylpyrrolidone (PVP) favored the enhanced stabilization of graphite nanoparticles. The addition of Triton X-100 (TX-100) resulted in an improved stabilization of carbon black. Based on these empirical studies, a methodology was derived, which supports the application of suitable dispersants in printable dispersions.