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The purpose of this paper is to prepare stabile emulsions with 0–15% of colloidal silica and high monomer/water ratio and to investigate the influence of silica addition and surface modification on the polyacrylate properties.

Improving the properties of the composite can be achieved by optimizing the compatibility between the phases of the composite system with improving the interactions at the matrix/filler interface. Therefore, the silica surface was modified with nonionic emulsifier octylphenol ethoxylate, cationic initiator 2,2'-azobis-(amidinopropane dihydrochloride) and 3-methacryloxypropyltrimethoxysilane and polyacrylate/silica nanocomposites were prepared via in situ emulsion polymerization. Particle size distribution, rheological properties of the emulsions and morphology, thermal properties and mechanical properties of the film prepared from the emulsions were investigated.

Polyacrylate/silica systems with unmodified silica, silica modified with nonionic emulsifier and cationic initiator have micrometer, while pure PA matrix and systems with silica modified with silane have nanometer particle sizes. Addition and surface modification of the filler increased emulsion viscosity. Agglomeration of silica particles in composites was reduced with silica surface modification. Silica filler improves thermal stability and tensile strength of polyacrylate.

This paper provides broad spectrum of information depending on filler surface modification and latex preparation via in situ emulsion polymerization and properties with high amount of filler and monomer/water ratio with the aim that prepared latex is suitable for film formation and final application.

The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.

Graphite-based resistors were made of thick-film pastes with different graphite-to-glass mass fraction were prepared and examined. Sheet resistance, temperature coefficient of resistance, impact of humidity and short-term overload were investigated. The properties of the layers fired in atmospheres of air at 550°C and nitrogen at 875°C were compared.

Graphite-based resistors with various graphite-to-glass ratios made possible to obtain a wide range of sheet resistance from single O/square to few kO/square. These values were dependent on firing atmosphere, paste composition and the number of screen-printed layers. The samples made of paste with 1:1 graphite-to-glass ratio exhibited the temperature coefficient of resistance of about −1,000 ppm/°C, almost independently on the firing atmosphere and presence of a top coating. The resistors fired in the air after coating with overglaze, exhibited significantly lower sheet resistance, reduced impact of humidity and improved power capabilities.

In this paper, graphite-based resistors for applications in typical high-temperature cermet thick-film circuits were presented, whereas typical graphite-based resistors were fabricated in polymer thick-film technology. Owing to very low cost of the graphite, the material is suitable for low-power passive circuits, where components are not subjected into high temperature, above the typical temperature of operation of standard electronic components.

The purpose of this work was to characterize NiMn₂O₄ spinel-based thermistor powder, to use it in screen printing technology to fabricate temperature sensors, to study their performance for different sintering temperatures of thermistor layer, with and without insulative cover, as well as to investigate stability of the fabricated thermistors and their applicability in water quality monitoring.

After the characterization of starting NiMn₂O₄ spinel-based thermistor powder, it was converted to thick film paste which was screen printed on alumina substrate. Thermistor layers were sintered at four different sintering temperatures: 980°C, 1050°C, 1150°C and 1290°C. An interdigitated pattern of Ag-Pd conductive layer was used to reduce the resistance. Temperature-resistance characteristics were investigated in air and water, with and without insulative cover atop the thermistor layer. Stability of the fabricated thermistors after aging at 120°C for 300 h was also examined.

Thick film NiMn₂O₄ spinel thermistors, prepared by screen printing and sintering in the temperature range 980°C–1290°C, exhibited good negative temperature coefficient (NTC) characteristics in the temperature range −30°C to 145°C, including high temperature coefficient of resistance, good stability and applicability in water.

This study explores the range of sintering temperature that can be applied for NiMn₂O₄ thermistor thick films without compromising on the temperature sensing performance in air and water, as well as stability of the thermistors after aging at elevated temperatures.

Degradable mulch film (DMF) is a potential alternate to polyethylene (PE) mulching. In this regard, the purpose of this paper is to explore the effects and paths of natural disaster shock and risk aversion influencing farmers’ DMF adoption.

This research is conducted by collecting cross-sectional data of corn farmers in Zhangye, China. First, by using the Tobit model, the paper attempts to explore the effects of natural disaster shock and risk aversion influencing farmers’ DMF adoption. Second, IV-Tobit model is applied to deal with endogenous problems between risk aversion and DMF adoption. Additionally, the researchers used a moderating model to analyze feasible paths of natural disaster shock and risk aversion impacting farmers’ DMF adoption.

The outcomes show that natural disaster shock and risk aversion significantly and positively affect farmers’ DMF adoption. Though risk aversion plays a significant moderating effect in influencing farmers’ DMF adoption by natural disaster shock, the moderating effect has a serious disguising effect. By considering the heterogeneity of risk aversion, the paper further confirms that if the intensity of natural disaster shock is increased by one unit, the intensity of MDF adoption by farmers with high-risk aversion also tends to increase by 15.85%.

This study is the pioneer one, which is evaluating the intensity of farmers’ DMF adoption from adoption ratio, investment amount, labor input and adoption time. Additionally, the research provides important guidelines for policymakers to motivate medium and low-risk aversion farmers to adopt DMF.

This paper aims to investigate the wear behaviour of different materials for cylinder liners and piston rings in a linear reciprocating tribometer with special focus on the wear of the cylinder liner in the boundary lubrication regime.

Conventional nitrided steel, as well as diamond-like carbon and chromium nitride-coated piston rings, were tested against cast iron, AlSi and Fe-coated AlSi cylinder liners. The experiments were carried out with samples produced from original engine parts to have the original surface topography available. Radioactive tracer isotopes were used to measure cylinder liner wear continuously, enabling separation of running-in and steady-state wear.

A ranking of the material pairings with respect to wear behaviour of the cylinder liner was found. Post-test inspection of the cylinder samples by scanning electron microscopy (SEM) revealed differences in the wear mechanisms for the different material combinations. The results show that the running-in and steady-state wear of the liners can be reduced by choosing the appropriate material for the piston ring.

The use of original engine parts in a closely controlled tribometer environment under realistic loading conditions, in conjunction with continuous and highly sensitive wear measurement methods and a detailed SEM analysis of the wear mechanisms, forms an intermediate step between engine testing and laboratory environment testing.

This paper aims to gain an understanding of the behaviour of iron ore when melted by a laser beam in a continuous manner. This fundamental knowledge is essential to further develop additive manufacturing routes such as production of low cost parts and in-situ reduction of the ore during processing.

Blown powder directed energy deposition was used as the processing method. The process was observed through high-speed imaging, and computed tomography was used to analyse the specimens.

The experimental trials give preliminary results showing potential for the processability of iron ore for additive manufacturing. A large and stable melt pool is formed in spite of the inhomogeneous material used. Single and multilayer tracks could be deposited. Although smooth and even on the surface, the single layer tracks displayed porosity. In case of multilayered tracks, delamination from the substrate material and deformation can be seen. High-speed videos of the process reveal various process phenomena such as melting of ore powder during feeding, cloud formation, melt pool size, melt flow and spatter formation.

Very little literature is available that studies the possible use of ore in additive manufacturing. Although the process studied here is not industrially useable as is, it is a step towards processing cheap unprocessed material with a laser beam.

Drawing on the discursive properties of placemaking theory, this paper discusses the development of film tourism in Crete from the release of the award-winning Zorba the Greek (dir. Michael Cacoyannis, ZG) to date. The approach is “genealogical,” seeking to explain how ZG-inspired tourism on Crete ended up being more than about the film itself owing to historical contingency.

This study aims to study the gas film stiffness of the spiral groove dry gas seal.

The present study represents the first attempt to calculate gas film stiffness in consideration of the slipping effect by using the new test technology for dry gas seals. First, a theoretical model of modified generalized Reynolds equation is derived with slipping effect of a micro gap for spiral groove gas seal. Second, the test technology examines micro-scale gas film vibration and stationary ring vibration to determine gas film stiffness by establishing a dynamic test system.

An optimum value of the spiral angle and groove depth for improved gas film stiffness is clearly seen: the spiral angle is 1.34 rad (76.8º) and the groove depth is 1 × 10^–5 m. Moreover, it can be observed that optimal structural parameters can obtain higher gas film stiffness in the experiment. The average error between experiment and theory is less than 20%.

The present study represents the first attempt to calculate gas film stiffness in consideration of the slipping effect by using the new test technology for dry gas seals.

The visitor economy of Forks now clearly relies upon a niche form of tourism – as fans of The Twilight Saga are drawn to the setting and filming location of the films. The purpose of this study is to consider the process of diversification and subsequently present recommendations that could inform a future diversification strategy for Forks, in preparation for a post-film tourism scenario.

The research methods employed in this study have two interlinked but distinct elements. Firstly, the Twilight Effect in Forks (WA, USA) is considered as an illustrative case study to shed light on the issues facing a destination that has seen a tourism boom as a direct result of popular culture – The Twilight Saga Franchise. Secondly, a scenario thinking and planning approach is applied when considering the “long-view” future of tourism in Forks.

This article presents a post-film tourism future scenario for Forks; it suggests tourism diversification and a shift towards cultural heritage and wellness. Forks is well placed to afford such tourism experiences, as it offers unique cultural and natural characteristics; furthermore, these could be utilised to create and maintain a distinctive destination image. In doing so a more socially and environmentally sustainable industry can be established, one which supports the local community, including the Quileute tribe.

The article offers original discussions within the film-tourism literature with novel approaches to understanding the management and pre-planning opportunities for destinations that have become popular film tourism locations, with the application of a “Tourism Diversification Model”. The model is adapted from Ansoff Matrix and can be applied as a framework in future studies exploring destination diversification. The investigation of Forks as a post-film tourism case study alone is unique, and the discussions and findings presented are original.

Endwall film cooling protects vane endwall by coolant coverage, especially at the leading edge (LE) region and vane-pressure side (PS) junction region. Strong flow impingement and complex vortexaa structures on the vane endwall cause difficulties for coolant flows to cover properly. This work aims at a full-scale arrangement of film cooling holes on the endwall which improves coolant efficiency in the LE region and vane-PS junction region.

The endwall film holes are grouped in four-holes constructal patterns. Three ways of arranging the groups are studied: based on the pressure field, the streamlines or the heat transfer field. The computational analysis is done with the k-ω SST model after validating the turbulence model properly.

By clustering the film cooling holes in four-holes patterns, the ejection of the coolant flow is stronger. The four-holes constructal patterns also improve the local coolant coverage in the “tough” regions, such as the junction region of the PS and the endwall. The arrangement based on streamlines distribution can effectively improve the coolant coverage and the arrangement based on the heat transfer distribution (HTD) has benefits by reducing high-temperature regions on the endwall.

A full-scale endwall film cooling design is presented considering interactions of different film cooling holes. A comprehensive model validation and mesh independence study are provided. The cooling holes pattern on the endwall is designed as four-holes constructal patterns combined with several arrangement choices, i.e. by pressure, by heat transfer and by streamline distributions.