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The purpose of this paper is to synthesize a polyacrylate-based dispersant with a determined target molecular weight for oily systems and to determine the optimal dispersant level and monomer ratio of the dispersant.

The dispersant was synthesized by conventional radical polymerization using methacrylic acid, butyl acrylate and dimethylamino ethyl methacrylate as the monomer. It was characterized by Fourier transform infrared spectroscopy, nuclear magnetic hydrogen spectroscopy, gel permeation chromatography and thermogravimetric analysis. The dispersant was used to disperse TiO₂, and the performance of the dispersant was evaluated by measuring the viscosity, particle size and dispersive force of the slurry.

The dispersant exhibited high thermal stability and was successfully anchored to the surface of the TiO₂ pigment. When used to disperse a TiO₂ slurry, it effectively made the TiO₂ slurry more fluid, indicating its strong viscosity-reducing properties. The viscosity, particle sizes and dispersion capabilities of the TiO₂ slurry were found to vary depending on the contents and monomer ratios of the dispersant.

P(MAA-BA-DM) dispersant increases the wettability of TiO₂ only in oily solvents but not in aqueous solvents.

P(MAA-BA-DM) dispersant makes it easier to disperse TiO₂ pigments in oily solvents, increasing the amount of pigment in the solvent and making the preparation of highly pigmented pastes easier.

A dispersant containing suitable carboxyl and tertiary amine groups was initially synthesized to disperse TiO₂ in an oily system. The findings are anticipated to be used in the formulation of pigment concentrates, industrial coatings and other solvent-based coatings.

This paper aims to present a requirements analysis for the processing of water-based electrode dispersions in inkjet printing.

A detailed examination of the components and the associated properties of the electrode dispersions has been carried out. The requirements of the printing process and the resulting performance characteristics of the electrode dispersions were analyzed in a top–down approach. The product and process side were compared, and the target specifications of the dispersion components were derived.

Target ranges have been identified for the main component properties, balancing the partly conflicting goals between the product and the process requirements.

The findings are expected to assist with the formulation of electrode dispersions as printing inks.

Little knowledge is available regarding the particular requirements arising from the systematic qualification of aqueous electrode dispersions for inkjet printing. This paper addresses these requirements, covering both product and process specifications.

Proposes to discuss the implementation of biological methods of the reinforcement and protection of slopes and dissemination to designers and builders of earthen structures.

The methodology of the process developed consists of field experiments including plant selection, preparation of the slope, hydroseeding mass composition, structure and rheological properties, as well as observation of the growing process and proper management of the layer covering. Laboratory tests and field experiments were conducted.

The research results confirm that covering slopes with a hydroseeding layer contributes to a reduction of the erosion process. The most important effect of the protection process is the creation of favorable conditions for seedlings growing in the third leaf phase with the effect of compact green cover.

The research results could be an important basis for the development of legislation acts related to road building, including proper slope management, together with seeding, underseeding and prototechnical operations that should be done during the first two years for both shaded and sunny slopes. The next step should be the training of designers and builders, and implementation of the technology.

This technology is new in Poland. The authors have realized several hundred slopes with this technology. However, for further improvement of slopes, protection was a necessary realization of the research discussed in the paper.

Heat capacity enhancement is important for variety of applications, including microchannel cooling and solar thermal energy conversion. A promising method to enhance heat capacity of a fluid is by introducing phase change particles in a flow system. The purpose of this paper is to investigate heat capacity enhancement in a microchannel flow with the presence of phase change material (PCM) particles.

Discrete phase model (DPM) and homogeneous model have been compared in this study. Water is used as the carrier fluid and lauric acid as the PCM particles with different volume concentrations, ranging from 0 to 10%. Both the models neglect the particle‐particle interaction effects of PCM particles.

The DPM indicates that presence of 10% volume concentration of PCM particles does not cause an increase in the pressure drop along the channel length. However, prediction from the homogeneous model shows an increase in the pressure drop due to the addition of nanoparticles in such a way that 10% volume concentration of particles causes 34.4% increase in pressure drop.

The study covers only 10% volume concentration of PCM particles; however, the model may be modified to include higher volume concentrations. The laminar flow is considered; it may be extended to study the turbulence effects.

This work provides a starting framework for the practical use of different PCM particles, carrier fluid properties, and different particle volume concentrations in electronic cooling applications.

The work presented is original and the findings will be very useful for researchers and engineers working in microchannel flow in cooling and thermal storage applications.

Discusses the use of a corporate Internet in a geographically‐spread consulting firm, James Martin & Co., to share ideas, vision, client information and results. Illustrates with examples. Applications include a quarterly Employee Attitude Survey and regular discussion forums. Proposes that a well‐designed corporate intranet is a highly effective method of making intangible vision and mission pledges more tangible.

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.

This is essentially a method of producing hard‐cured films from a liquid coating, where the solvent has been removed and replaced by a liquid monomer. This reaction is instigated by a free radical mechanism induced by either electron‐beam or more generally by ultra‐violet radiation.

Various types of ionic and non‐ionic dispersants have been classified by their ability to stabilise titanium dioxide pigment suspensions in water. It was found that some non‐ionic dispersants produced suspensions that exhibited full steric stabilisation as opposed to electrosteric stabilisation that occurs with ionic dispersants. A high level of steric stabilisation was found to relate to greater flocculation resistance in both the wet and dry phases, which can result in improved paint stability and higher opacity.

The purpose of this paper is to investigate the tribological performance of graphene oxide (GO) sheets as water-based lubricant additive when ultra-high molecular weight polyethylene (UHMWPE) plates slid against 316L stainless steel ball using a reciprocating tribometre.

The factors influencing the tribological performance were considered, including the viscosity of the GO dispersion, normal load, sliding velocity and the roughness of UHMWPE. The surface microstructure and properties of UHMWPE were studied by means of scanning electron microscopy, laser confocal microscopy, Raman spectroscopy and contact angle measurements.

The results revealed that the GO dispersion reduced friction and sliding-wear. The surface images of the wear UHMWPE plates indicated that GO sheets were prone to adsorption on the surface and form a thin physical tribofilms at the substrate.

Based on the experimental findings for the evolution of the microstructure morphology and the development of subsurface cracks, less debris and cracking can be observed in the UHMWPE plates lubricated by GO dispersion.