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The purpose of this paper is to propose a nanodiamond-particle-loaded food-grade lubricating oil, a nanolubricant, that can be used over a broad range of loads in factories (low load applications like conveyor systems and high load applications like heavy machinery).

Tribological performance of the nanolubricant was studied at both load levels. A typical factory-sized conveyor belt used for beverage packaging (aluminium cans, glass and PET bottles) was employed for the low load range. Coefficients of friction and wear scars were measured and the lubricating performance was quantified. A four-ball tester was used to characterise the performance of the nanolubricant as per ASTM D2783/D4172. A comparison between the nanolubricant and baseline oils was carried out.

Results show an overall decrease in the coefficients of friction and wear scars for all packages at low pressures when the nanolubricant is used. They also show a better friction-reduction performance in the high load regimes. The results indicate that the nanolubricant is versatile in both ranges of loading.

The current protocols for lubrication in the food and drink factories involve the use of water-based detergents for the conveyor lines and industry-grade oils for the machinery. The use of a single and versatile lubricant for both ranges of loads may have a positive impact on the sustainability and environmental performance of the sector.

Beverage processing and packing factories need their mechanised conveyor systems suitably lubricated to avoid excessive friction between the containers and the load-bearing surface of the conveyors (e.g. belts or chains). Other areas of the conveying systems, such as motors, gears, rollers and bearings, also need suitable lubrication to prevent failure and lengthen their operating life. There is a myriad of lubricants and lubricating solutions for each of these areas independently, but there is no commercial lubricating fluid that could be used on both successfully.

The purpose of this research paper is to investigate the changes in free volume by adding acrylate modified nanodiamond particles. In this study, a cross-linked thiol-ene (T) network was obtained under ultraviole light. The changes in free volume were analyzed when acrylate-modified nanodiamond (M-ND) particles were added to the nanocomposites obtained. Positron annihilation lifetime spectroscopy (PALS), a well-established method, was used for this analysis. In addition, the effect of nanocomposites containing different ratios of acrylate M-ND particles (1, 2, 3 and 5 Wt. %) on the surface and the thermal properties were also examined.

The impact of different quantities of acrylate M-ND on the free volume and surface morphological properties of thiol-ene polymer networks were studied by using scanning electron microscopy, differential scanning calorimetry, attenuated total reflection, Fourier transform infrared spectroscopy, PALS and thermogravimetric analysis measurements.

The thermal properties of T/M-ND were found to depend on the weight percentages of the M-ND content. For increasing weight percentages of M-ND added to thio-lene polymer networks, the glass transition temperature (T_g) increased from 103°C to 154°C. The ortho-positronium (o-Ps) lifetime (free volume) and free volume fraction characterization of T/M-ND nanocomposites were investigated using PALS. Increasing temperature caused both the o-Ps lifetime (free volume) to change with increasing saturation and to linearly increase the intensity; however, an increasing weight percentage of M-ND caused no change at all for the o-Ps lifetime (free volume) and the free volume fraction.

According to published literature, and to the best of the authors’ knowledge, this is the first time a study examining the free volume properties in a thiol-ene system has been carried out.

This paper aims to provide a detailed review of gas sensor research which exploits the properties of nanomaterials and nanostructures.

Following an introduction, this paper discusses developments in gas sensors based on carbon nanotubes, titanium dioxide nanotubes, graphene, nanocrystalline diamond and a range of metal oxide nanomaterials. It concludes with a discussion of this research and its commercial potential and a list of references to the research considered in the main text.

Gas sensors based on a multitude of nanomaterials are the subject of a global research effort which has generated an extensive literature. Prototype devices have been developed which respond to numerous important gases at concentrations which correspond well with industrial requirements. Other critical performance characteristics have been studied extensively and the results suggest commercial prospects for these technologies.

This paper provides details of the highly topical field of nanomaterial-based gas sensor research.

The purpose of this paper is to discuss the dispersion capacity and tribological behavior of liquid paraffin added by diamond nanoparticles.

The structure of the modified diamond nanoparticles which are prepared by oleic acid (OA) is observed by scanning electron microscopy (SEM) and infrared spectroscopy (IR). The dispersivity of these nanoparticles in liquid paraffin is measured by nanoparticle analyzer. The tribological behavior of adding diamond nanoparticles in liquid paraffin is evaluated by using a ball‐on‐ring wear tester.

The measurement results reveal the dispersion capability of OA modified diamond nanoparticles and indicate the dispersing stability in liquid paraffin of the OA which is bonded to the surface of diamond nanoparticles through esterification. It is found from wear testing results that the diamond nanoparticle as additive in liquid paraffin at proper concentration shows better tribological properties for anti‐wear (AW) and antifriction than the pure paraffin oil and different AW ability depending on the particle size.

It is shown in the paper that by reducing friction and AW, the lubricant prepared by the methods described can prolong operating hours of machinery.

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.

This paper aims to perform the lattice Boltzmann simulation of conjugate natural convection heat transfer, heat flow visualization via heatlines approach and entropy generation in a partitioned medium filled with Ag-MgO (15-85%)/water.

The lattice Boltzmann method (LBM) is used to predict the dynamic and thermal behaviors. Experimental correlations for dynamic viscosity and thermal conductivity versus solid volume fraction are used. The study is conducted for the ranges of Rayleigh number 10³ ≤ Ra ≤ 10⁶, the partitioner thickness 0.01 ≤ δ ≤ 0.9, its position 0.15 ≤ X_s ≤ 0.85 and the hybrid nano-suspensions volume fraction 0% ≤ ϕ ≤ 2%.

The effects of varying of controlling parameters on the convective flow patterns, temperature contours, heat transfers, the heatlines and the entropy generation are presented. It has been found that the maximum rate of heat transfer enhancement occurs for low Ra numbers (10³) and is close to 13.52%. The solid thickness d and its horizontal position X_s have a substantial influence on the heat transfer rate, flow structure, heatline, total entropy generation and Bejan number. Besides, the maximum heat transfer is detected for high Ra and δ ≈ 1 and the percentage of augmentation is equal to 65.55% for ϕ = 2%. According to the horizontal position, the heat transfer remains invariant for Ra = 10³ and takes a maximum value near the active walls for Ra ≥ 10⁴. The total entropy generation increases with Ra and decreases with ϕ for Ra = 10⁶. The increase of ϕ from 0 to 2% leads to a reduction in close to 40.76%. For this value of Ra, the entropy is the maximum for δ = 0.4 and X_s = 0.35 and X_s = 0.65%. Moreover, as the Ra increases the Bejan number undergoes a decrease. The Bejan number is the maximum for Ra = 10³ independently to δ and X_s. The superior thermal performance manifests at low Ra and high value of δ independently to the positions of the conducting body.

The originality of this paper is to analyze the hybrid nano-additive effects on the two-dimensional conjugate natural convection in a partitioned medium using the LBM. The experimental correlations used for the effective thermal conductivity and dynamic viscosity give credibility to our study. Different approaches such as heatlines and entropy generation are used.

The present work aims to formulate nanolubricants and improve antiwear, antifriction and extreme pressure (EP) performances of castor oil (CO) with surface-modified CuO nanoparticles as an additive in the boundary lubrication regime.

In this study, CuO nanoparticles are modified with a surfactant sodium dodecyl sulfate (SDS) by means of a chemical method. These modified nanoparticles with varying concentrations of 0.1, 0.25, 0.5 and 1.0%w/v were used to formulate the nanolubricants. The tribological properties of non-formulated and formulated CO were examined using a four-ball tester. The tribological test results were compared with paraffin oil (PO) for similar compositions.

The nanoparticle concentrations in base oils were optimized by wear scar diameter (WSD) and load carrying capacity during antiwear and EP tests, respectively. In the antiwear test, the maximum reductions in WSD were 28.3 and 22.2 per cent; however, the coefficient of friction was reduced by 34.6 and 17.3 per cent at optimum nanoparticle concentrations in CO and PO, respectively. A significant improvement in the weld load was observed for both nanolubricants.

This work indicates that nanoparticle-based CO in industrial applications provides on par or better results than mineral oil. Also, it has a negligible hazardous impact on our eco-system.

This paper aims to describe the nanosensor research reported at the “Nanomaterials: Applications & Properties 2012” conference, held in the Ukraine in September 2012.

Following a short overview of the event, this paper describes the nanosensor research reported at the conference, arranged according to the variables involved, i.e. chemical sensing, gas sensors and physical sensing. Brief consideration is also given to developments in power sources.

This shows that, although nanosensors were not a major theme at the event, several innovative developments for sensing a range of molecular and physical variables were reported.

This paper provides details of the nanosensor research reported at “Nanomaterials: Applications & Properties 2012”.

The purpose of this paper is to study the load capacity of nanoparticles-laden gas film (NLGF) in thrust bearing.

SiO₂ nanoparticles were added into gas to form an NLGF. The nanoparticles volume fraction in the film was controlled by a vibrator. The film thickness and the film pressure were measured by a micro cantilever displacement sensor and a membrane pressure sensor, respectively. The total load that makes the film thickness keeping constant was quantified, and then, the film load capacity was obtained.

The investigation shows that nanoparticles can enlarge the film load capacity remarkably; even a little amount of nanoparticles (0.01 per cent) could lead to a sharp rise. With the increase of nanoparticles volume fraction, load capacity increases. However, the increment of load capacity decreases gradually. In addition, the film pressure variation proves the enhancement effect of nanoparticles on the film load capacity.

The paper is restricted to the findings based on NLGF, which is formed by dispersing SiO₂ nanoparticles in gas film as an additive. The experimental results are applicable within the range of nanoparticles volume fraction of 0.01-0.33 per cent.

The fact that nanoparticles could enlarge the gas film load capacity is verified by experiment for the first time. This study reveals the corresponding relation between nanoparticles volume fraction and the film load capacity.

The paper aims to examine the boundary layers of a three-dimensional stagnation point flow of Al-Cu nanoparticle-suspended water-based nanofluid in an electrically conducting medium. The effect of magnetic field on second-order slip effect and convective heating is also taken into account.

The thermophysical properties of alloy nanoparticles such as density, specific heat capacity and thermal conductivity are computed using appropriate formula. The non-linear parabolic partial differential equations are transformed to ordinary differential equations and solved by shooting technique.

The influence of compositional variation of alloy nanoparticle, nanoparticle concentration, magnetic effect, slip parameters and Biot number are presented for various flow characteristics. Interesting results on skin friction and Nusselt number are obtained for different composition of aluminium and copper.

A novel result of the analysis reveals that impact of magnetic field near the boundary is suppressed by the slip effect.