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The purpose of this paper was to prepare and evaluate a nanosized mixed calcium iron oxide as a high heat-resistant pigment. Heat-resistant pigments can be defined as chemical substances that impart color to a substrate or binder and retain their color and finish at elevated temperatures. Mixed metal oxides have been widely used as pigments in coating formulations.

This work presents synthesis of nanosized calcium iron oxide as an inorganic pigment by using simple synthesis technique, namely, solid-state calcination method, to study its heat and corrosion resistance. The prepared pigment was characterized by using X-ray diffraction, infrared spectroscopy, scanning electron microscopy and inductive coupling plasma. It was incorporated into paint formulations, and the heat, corrosion and mechanical resistance of dry paint film was evaluated.

In this work, the prepared calcium iron oxide pigment showed excellent heat and corrosion resistance.

Heat-resistant coatings are required for industrial applications, mainly for reactors, exhaust pipes, space craft, stacks and similar equipments that are permanently and occasionally exposed to elevated temperatures. It was previously quite difficult to formulate heat-resistant organic coatings because of binder deficiencies; new vehicles for such applications are now available. Thus, the development of silicon resins has markedly advanced the utility of heat-resistant paints. High-temperature pigments are inorganic chemical compounds that impart and retain their color and finish to a substrate or binder at elevated temperatures.

The nanosized mixed calcium iron oxide could be used as a pigment in paint formulations. It was found that it significantly enhances the heat, corrosion and mechanical resistance. It can also find numerous applications in other paint formulations for surface coating.

The paper shows how the pigment consisting nanosized mixed calcium iron oxide could be used in heat-resistant paint formulations for coating metal surfaces.

The purpose of this paper is to prepare new economical thermal resistant coatings containing white sand (WS) and kaolin (K) fillers, which are cheap natural ores in Egypt and are sources for ceramic materials such as SiO₂ and Al₂O₃.

This paper investigates the effect of heat at 500°C on the durability of mild steel samples coated with silicon coatings. The coated plates were exposed to elevated temperatures according to ASTM D 2485 to determine their stability. Thermal gravimetric analysis and scanning electron microscopy were used to investigate the thermal stability of the modified films.

It was revealed that the composite fillers can enhance the thermal stability of silicon coatings. Another advantage of using the prepared composite fillers is promoting the dryness of silicon resin without heat.

Different natural ores were used as ceramic filler to enhance the thermal stability of silicon coatings.

New economical thermal-resistant coatings containing white sand and kaolin were prepared to replace the expensive thermal coatings; also, they can be used in industries other than coatings, e.g. paper, rubber and plastics composites.

This paper aims to analyze the friction heat conduction and entransy of two friction linings in the high‐speed slide accident of a mine friction hoist.

Firstly, the dynamic thermophysical properties were analyzed and their fitting equations were also obtained. Additionally, the dynamic heat partition ratio was obtained according to the dynamic thermophysical properties. Then, a simple method was developed to solve the temperature rise of friction lining. Finally, based on the theoretical model of temperature rise, the entransy of friction lining with respect to T and t were gained.

The error of temperature rise between simulation result and experiment result is less than 7 per cent, which proves that the theoretical model is correct. The entransy decreases with the temperature below 40°C and it increases after 40°C. The entransy of lining K is a little higher than that of lining G within 19 s, but the entransy of lining G is much higher than lining K after 19 s and the entransy difference gets great gradually. It is indicated that the lining K has good heat‐resistant property which is of great benefit to the tribological property of friction lining.

The authors' study provides a fundamental basis for developing a new friction lining with good heat‐resistant property, and it also brings forward a new quantitative method to evaluate the heat‐transfer capability of friction materials.

A simple method was introduced to calculate the temperature rise of friction lining with the consideration of dynamic thermophysical properties and dynamic heat partition ratio. And the entransy of friction lining was obtained to evaluate the heat‐transfer capability of friction linings quantitatively.

In this special feature details are given of those British paints which can be described as corrosion‐resistant primers, both one‐ and two‐pack. The materials are generally classified according to the base or pigment which actively prevents corrosion—e.g. metallic zinc in zinc/epoxy formulations— or by the base which produces a barrier action against corrosion, e.g. bitumen in bituminous paints. Exceptions to this are the etching primers, which are separately classified. About 300 primers are described, the manufacturers' names and addresses being cross‐indexed and listed separately on page 48.

The purpose of this paper, an original research paper, is to study the optimization of material removal rate (MRR) in ultrasonic machining of polycarbonate bulletproof glass and acrylic heat-resistant glass. The machining of these materials is a very tough job. There are so many constraints which need to be taken into account while machining, but without proper knowledge of material properties and machining parameters, machining is not possible. This paper gives basic knowledge about polycarbonate bulletproof and acrylic heat-resistant glass and provides ways as to how these types of materials are processed or machined.

The Taguchi method was utilized to optimize the ultrasonic machining parameters for drilling these advanced materials. The relationship between MRR and other controllable process parameters such as concentration of slurry, type of abrasive, abrasive grit size, power rating, concentration of HF acid and type of tool material has been analyzed by using the Taguchi approach.

Through the Taguchi analysis, it is concluded that types of abrasive and HF acid concentrations have a significant role to play in MRR for both materials; in which, type of abrasive have 72.91 and 72.96 percent contribution in MRR for polycarbonate bulletproof and acrylic heat-resistant glass, respectively. Similarly, HF acid concentration has 14.70 and 14.65 percent contribution in MRR for polycarbonate bulletproof and acrylic heat-resistant glass, respectively. The MRR was improved by 34.44 percent in polycarbonate bulletproof glass and 29.25 percent in acrylic heat-resistant glass.

After experimental investigation, the results of the Taguchi modal are validated.

MANY of the creep‐resistant and heat resistant metals used in the aircraft industry, such as the nickel‐based alloys, titanium and its alloys, stainless steels and high temperature alloy steels must be subjected to heat treatment to relieve stresses. This is necessary because, when stretched, pressed or manipulated, such materials work, harden. In the process of heat treatment, formidable problems of oxidation and scale formation are encountered which demand lengthy descaling operations after treatment, or the use of controlled‐atmosphcrc or vacuum furnaces for oxidation‐susceptible metals like titanium. Within the last two years, however, development work by Rolls‐Royce Ltd. has produced some very effective new protective coatings, which, as a result of subsequent co‐operation with F. W. Berk and Co. Ltd., have now been made generally available under the name of ‘Berkatekt’ coatings. coatings are licensed for use under Patents applied for by Rolls‐Royce Ltd.

Coatings Solve Descaling Problems. Formidable problems of oxidation and scale formation are encountered in the heat treatment of creep‐resistant and heat‐resistant metals which demand lengthy descaling operations after treatment, or the use of controlled‐atmosphere or vacuum furnaces. Within the last two years, however, Rolls‐Royce Ltd. have developed protective coatings which, as a result of subsequent co‐operation with F. W. Berk & Co. Ltd., are available under the name of Berkatekt for protecting the metals from oxidation, intergranular corrosion and decarburisation during treatment.

ALL ‘plastics’ are generally divided into two groups: the ‘thermoplastics’, which are formed by heating, can be re‐heated after forming, and re‐formed almost ad lib, such as celluloid, xylonite, rhodoid, cellophane, and perspex; and the ‘thermosetting plastics’, which are also formed by heating but cannot yet be re‐formed by the application of heat or any other means, probably the best‐known example of which is the thermosetting variety of bakelite.

The presence of Bacillus sporothermodurans in retail UHT milk along with milk from different points of a processing line was determined. This paper aims to investigate the effect of chilling, pre‐heating, UHT, reprocessing and H₂O₂ individually and in combination on the survival of B. sporothermodurans in broth.

Standard plate counts were conducted for all milk samples and isolates from UHT milk were characterised using PCR. BS vegetative cells and spores in broth were subjected to various stresses encountered, during UHT processing of milk. Survival counts were conducted after all treatments.

B. sporothermodurans was detected in retail UHT milk packs from only one processor. UHT treatment at 140°C for 4s eliminated B. sporothermodurans in broth. The combination of chilling and UHT was more effective in eliminating B. sporothermodurans spores than UHT treatment alone. H₂O₂ was also effective in eliminating B. sporothermodurans spores after 15 min of exposure. The adopted real time (RT) PCR with SYBR Green method was effective for the confirmation of B. sporothermodurans.

This research is the first to be conducted with regards to the detection of B. sporothermodurans in UHT milk in South Africa and determining the effect of UHT processing stresses on their survival. These results can be used to design processing parameters so as to effectively eliminate B. sporothermodurans spores during UHT processing. This research is the first in which RT PCR with SYBR Green has been used to characterise B. sporothermodurans.