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New, undestroyed greases of the same brands as those used in a field test, described in Part 1, were examined using conventional methods, such as the SKF V2F test, the roll stability test (ASTM D‐1831), the Grease Worker (ASTM D‐217), the torque test (ASTM 1478‐91), bleeding measurements ( IP 121), yield stress measurements, the 4‐ball test (ASTM D 2266‐86), base oil viscosity measurements, thickener content and the cone penetration test (ASTM D217‐88). The greases have also been tested with several new test methods developed at the University. A specification for relevant testing methods was drawn up and the connections between the tested parameters were investigated. It was found that the mechanical stability could be predicted with a combination of ASTM D‐1831 and the limiting shear stress coefficient γ. This coefficient is capable of predicting wear. It was found that the bearing temperature could be predicted by using the base oil viscosity.

This paper aims to determine the important role of acoustic wave devices in sensing applications such as automotive applications, industrial applications and commercial applications.

The paper provides a comprehensive overview of acoustic wave technology and highlights an example of one commercial implementation of its technology for sensing application: a commercially available real‐time, online threaded bolt viscosity sensor.

The commercially available viscosity sensor can be readily applied in field operations or installed directly on the equipment for continuous monitoring of viscosity to enable technicians/mechanics to test the oil in minutes.

The paper introduces a new product for the sensing industry.

Characterization of honey gathered importance since it has been widely used in both medical and domestic needs. In this fast moving mechanical life, people are bound to buy commercially available honey at markets. The purpose of this paper is to study the physical and thermal properties of such honey.

Four well‐known commercial honey samples in the Indian market were analyzed for their color, rheology and thermal properties.

Color of the samples varied from white to light amber according to United States Department of Agriculture method. Rheologies of the samples were studied between 10 and 30°C. Viscosities of samples varied from 1.31  to 96.7 Pa s according to the kind of honey and temperature of measurement. Controlled shear rate viscometry indicated the Newtonian behavior with a drop in viscosity as the temperature increases. Differential Scanning Calorimetry analysis indicated the inflection transition temperature (Tg) of the present investigation ranged between –51.40  and –30.64°C. Correlation between the Tg and the viscosity of the samples were significant.

There has been no report available on the Newtonian behavior of the commercial Indian honey samples. This paper will help the consumers to comprehend the standard of the honey sold in the Indian market. Distributors/manufacturers will also be aware of quality of honey, which will help further in the process development, transportation and storage.

The interaction between the silver powder and organic vehicle largely determines the rheological behavior of silver conductive paste. This study aims to prepare silver conductive paste with an organic vehicle system consisting of ethyl cellulose (EC) and terpineol/butyl carbitol acetate solvent mixtures. The study also aims to measure the rheological behaviors of the silver conductive pastes with different solvent mixtures, EC molecular weights and silver content, to investigate the interaction among the polymer, solvent and silver powder and determine the main factors affecting the thixotropic index and maximum silver content.

The rheological behaviors of silver conductive pastes with different solvent mixtures, EC molecular weights and silver content were investigated using viscometer.

The shear thinning became significant with increasing EC molecular weight. The EC solvation with higher molecular weight in solvent is better than that of EC with lower molecular weight. This leads to a stronger interaction between the silver powder and EC with higher molecular weight and consequently good silver particle dispersion. The relative viscosity of silver conductive paste at 10 s⁻¹ increases significantly with increasing silver content, but the relative viscosity at 100 s⁻¹ is much less sensitive to the silver content. The viscosities at low and high shear rate can be increased by increasing the silver content and EC molecular weight, respectively.

The interaction among the polymer, solvent and silver powder was investigated for the silver paste with high solid content. The main factors affecting the viscosities at high and low shear rates, thixotropic index and maximum silver content were determined.

A disadvantage found when conventional weather resistant powder coatings are compared to liquid coatings is their relatively poor flow properties. The flow of thermoset powder coatings depends on a number of factors, including the selection of suitable pigments and fillers, pigment concentration, additives such as flow agents, bake schedule, reactivity and structure of the resinous components, melt viscosity, and the viscosity profile during crosslinking. This paper reports about recently developed carboxyl terminated triglycidyl isocyanurate (TGIC) cured polyesters which result in powder coatings with remarkably improved flow properties due to the polyester's molecular structure and functionality and the viscosity profile during the curing process. These improvements have been reached without any prolongation of the gel time and without compromising the weathering resistance of the film. Such new powder coatings completely crosslink at 160°C within 15 minutes yielding films with excellent mechanical properties.

The purpose of this paper is to develop a high‐throughput approach to optimize printing of pigment‐based formulations.

A total of 40 formulations were robotically prepared by varying the concentrations of diethyleneglycol, glycerol and surfynol. In addition, a variety of inkjet printer (process) variables (voltage, pulse width and frequency) was varied. The combined influence of these two sets of variables on printing performance were determined, analysed and optimised using the Statistical Software Package (MODDE 8), which uses multiple linear regression and partial least square analysis.

The components diethyleneglycol and surfynol were observed to predominantly control viscosity and surface tension of all formulations, which voltage and pulse width were found to be the main factors controlling the spread of the droplet on the substrate.

Optimisation of pigment‐based formulations has typically involved the one‐by‐one systematic variation of components in a stepwise manner. The work reported here allowed the generation of a robust model allowing the properties of any new formulation to be accurately predicted. Importantly, the experimental tools and methods developed can be applied quite generally to the preparation of any new formulation for inkjet printing application.

Experimental design and high‐throughput technology allow new formulations to be accurately predicted for diverse inkjet applications.

The purpose of this paper is to investigate and contribute to a better understanding of cutting process characteristics using the proposed RBD Palm Olein-based organic mixed coolant.

In this research, refined, bleached and deodorized (RBD) Palm Olein is selected as the base oil for organic coolant and mixed coolant (base oil mixed with chemicals) to compare with the cutting performance of industrial water-soluble chemical (inorganic) coolant. Using coated carbide tool, JIS SS400 Mild Steel was tested in milling process. At fixed spindle speed, the relations between feed rate and depth of cut (DOC) on cutting temperature and surface roughness were investigated. Also, the dynamic viscosity, specific heat capacity and pH level for each coolant are taken into consideration.

As predicted, cutting fluid with lower viscosity removes more heat. The cutting temperature increased with increasing feed rate and DOC. However, surface roughness increased with increasing feed rate but decreased with increasing DOC. From the data gathered, the proposed RBD Palm Olein-based organic mixed coolant showed better heat removal properties than organic coolant and it produced a far better machined surface than inorganic coolant.

Overall, the proposed organic mixed coolant has shown great potential to be a good cutting fluid when balance between cooling properties and lubricity, and consistent quality of cutting fluids are sought to produce environmental friendly quality workpiece.

The purpose of this study is to determine the physicochemical and rheological parameters of Albizia lebbeck gum.

Physicochemical analysis was carried out using recommended methods. Gas chromatography mass spectrophotometer and Fourier transformed infra red (FTIR) analyses were carried out using their respective spectrophotometer. Scanning electron microscopy was carried out using scanning electron microscope, while rheological measurements were carried out using Ubbelohde capillary viscometer, digital Brookfield DV 1 viscometer and a rheometer.

Albizia zygia gum is an ionic gum with unique physical and chemical properties. Scanning electron micrograph revealed that the internal structure of the gum is porous with irregular molecular arrangement. Thermodynamic parameters of viscous flow indicated the existence of few inter- and intra-molecular interactions, and the attainment of transition state was linked to bond breaking. Coil overlap transition studies revealed the existence of dilute and concentrated regimes. The viscosity of the gum was also found to decrease with decrease in the charge of cation (such that Al3+ > Ca2+ > K+) and with increase in ionic strength.

The paper provided information on physicochemical and rheological characteristics/behaviour of Albizia zygia gum, of Nigerian origin. From this information, possible application of this gum in the food and pharmaceutical industries can be deduced.

The paper is original since information concerning Albizia zygia gum of Nigerian origin are not well documented as established in the work. It also adds values on the use of Albizia zygia gum, either on its own or in combination with other gums for industrial purpose.