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The performance of epoxy coating on metal substrate at low temperature and high humidity application has adverse effect on cure rate, film properties and adhesion. In recent years, several advanced amine cross-linking agents having superior curing ability at low temperature application environment have been introduced. The aim of this paper is to study the properties of epoxy-based coating cured with different cross-linking agents designed for low temperature application at different environmental conditions.

Series of cross linking agents such as modified cycloaliphatic amine (H1), polyamine adduct (H2), modified aliphatic ketamine (H3), phenalkamine (H4) and phenalkamide (H5) have been studied to evaluate their performance in epoxy compositions when cured at four environmental conditions, i.e. at ambient and sub-ambient temperatures with 60 and 90 per cent relative humidity, respectively. The effect of curing conditions was investigated by evaluating different physico-mechanical properties. Dynamic mechanical analyser technique was used to determine glass transition temperature (T_g) and cross-link density (ρ) of coatings. Anticorrosive properties of coatings also have been studied by electrochemical impedance spectroscopy.

The outcome of this study is expected to generate new insight into the curing behaviour of epoxy coating using different cross-linking agents which are recommended for low temperature application. Optimum physico-mechanical and corrosion resistance properties have been obtained by phenalkamine curing agent at low temperature and high humidity condition.

This study is an experimental approach to select the better cross-linking agent for low temperature application. Different test conditions were measured for understanding the performance of epoxy coating cured at different environmental condition.

The understanding reaction mechanism of the epoxy resin with cross-linking agent at different environmental condition is the great challenge and is hardly investigated in the literature. Therefore, in this research, the influence of climatic conditions and type of cross-linking agents on curing behaviour of epoxy-based coating was investigated.

The purpose of this paper is to report an experimental study on the effects of various parameters, such as varying flow velocities of water in the pipe, insulating the water pipe, and heating the pipe, to prevent pressurized water in a water hydraulic system from freezing under sub‐zero ambient temperature environment.

An experimental test rig was designed, fabricated, and set up to conduct several experiments to investigate the time taken for water to freeze under sub‐zero ambient temperature at −20°C and with the water initially at a higher temperature than the ambient.

The experiments show that it would take about 90 min for water in the pipe to freeze completely when there is no flow, or water is flowing at slow speed, in the pipe. The results also show that the use of insulation on the pipe would delay the freezing of water inside the pipe; and if used together with heating at several locations on the pipe, freezing of water inside the pipe could be prevented completely.

This paper usefully shows that insulation and heating in a water hydraulic system can prevent freezing of water in the pipe. The promising results of the experimental work mean that water might be able to replace oil in hydraulic systems on aircraft and other low‐temperature applications.

The purpose of this paper is to report the investigation of a low temperature application process for three‐layer polyethylene coating (3LPE) at 185‐195°C to meet the requirement of the coating temperature for X80 longitudinally welded pipe.

Plant coating and laboratory tests were performed to determine the properties of 3LPE coating coated at 185‐195°C.

The properties of the 3LPE coating, which was applied by using a suitable low temperature cured epoxy powder at temperature of 185‐195°C, were nearly the same as those of a 3LPE coating that had been applied at the normal coating temperature (200‐230°C).

Recommended acceptance criteria for 3LPE coatings applied at 185‐195°C are proposed. The research results met the requirements for external anti‐corrosion properties for X80 longitudinally welded pipe.

Currently heating and cooling in buildings is responsible for over 30% of the primary energy consumption in the United Kingdom with a similar amount in China. We analyze heat pumps and district thermal energy network for efficient buildings. Their advantages are examined (i.e., flexibility in choosing heat sources, reduction of fuel consumption and increased environmental quality, enhanced community energy management, reduced costs for end users) together with their drawbacks, when they are intended as means for efficient building heating and cooling.

A literature review observed a range of operating conditions and challenges associated with the efficient operation of district heating and cooling networks, comparing primarily the UK’s and China’s experiences, but also acknowledging the areas of expertise of European, the United States, and Japan. It was noted that the efficiency of cooling networks is still in its infancy but heating networks could benefit from lower distribution temperatures to reduce thermal losses. Such temperatures are suitable for space heating methods provided by, for example, underfloor heating, enhanced area hydronic radiators, or fan-assisted hydronic radiators. However, to use existing higher temperature hydronic radiator systems (typically at a temperatures of >70°C) a modified heat pump was proposed, tested, and evaluated in an administrative building. The results appears to be very successful.

District heating is a proven energy-efficient mechanism for delivering space heating. They can also be adaptable for space cooling applications with either parallel heating and cooling circuits or in regions of well-defined seasons, on flow and return circuit with a defined change-over period from heating to cooling. Renewable energy sources can provide either heating or cooling through, for example, biomass boilers, photovoltaics, solar thermal, etc. However, for lower loss district heating systems, lower distribution temperatures are required. Advanced heat pumps can efficiently bridge the gap between lower temperature distribution systems and buildings with higher temperature hydronic heating systems

This chapter presents a case for district heating (and cooling). It demonstrates the benefits of reduced temperatures in district heating networks to reduce losses but also illustrates the need for temperature upgrading where building heating systems require higher temperatures. Thus, a novel heat pump was developed and successfully tested.

The phenomenon of superconductivity has been studied for 90 years, with the latest surge in popularity occurring in the late 1980s, when high‐temperature superconductors were first created. In this time much progress has been made to create commercially viable applications of the technology and understand the theory behind the phenomenon. Furthermore, at a time when national science policy was undergoing close scrutiny, the high‐temperature superconductor boom served as a high‐profile case study of the role of government in spurring the acceptance of new technologies. This bibliography provides resources that chronicle the technological and scientific developments in the field since its discovery and the policy decisions and issues that governments and society made when faced with a possible scientific revolution.

The purpose of this paper is to characterize electrical properties of nickel-phosphorus (Ni-P) thin-film resistors made on FR-4 laminate in a wide range of temperature (from −180 to 20°C).

The study was performed using resistors made of Ni-P foil with two different thicknesses (0.1 or 0.05 μm) and sheet resistances (100 or 250 Ω/sq), respectively. The resistance rectangular resistors had length and width from the range between 0.59 and 5.91 mm. The resistance versus temperature characteristics and their distribution as well as resistors ' durability to low-temperature thermal shocks were investigated.

The results showed almost linear temperature dependence of resistance with a negative temperature coefficient of resistance of about −95 ppm/°C for 250 Ω/sq layer and −55 ppm/°C for 100 Ω/sq layer. A very small dimensional effect was observed for sheet resistance as well as for R(T) characteristic. Thin-film resistors are also characterized by very high durability to low-temperature thermal shocks.

The results presented in this paper can be very useful for low-temperature applications of thin-film resistors made on printed circuit boards. They suggest possibility of wide applications of these components in a wide temperature range.

Epoxy curing agents are used to cure epoxy resins by reacting with the epoxide groups or by promoting self‐polymerisation of the epoxy by catalytic action. Application characteristics and final physical properties can be tailored by the choice of curing agent. The purpose of this study was to reduce the cost of epoxy hardeners (polyamide and Mannich base, which are commercially available) without affecting the properties of epoxy system and which are also useable as low temperature curing in flooring.

To prepare cost effecting Mannich base curatives for low temperature working environment without significantly affecting the properties such as toughening, adhesion, chemical resistance, etc. various compositions were made by incorporating liquid epoxy resin.

Mannich base curatives were prepared by using different amounts of phenol/bisphenol‐A, formaldehyde and polyamines to obtain products having different amine value, viscosity and colour. Liquid epoxy resin was cured by these Mannich base hardeners prepared. Drying time of relevant thin films was observed. These curatives showed excellent curing property at low temperature as well high humid conditions.

Mannich base curatives, used in present work was synthesised from phenol, DETA and dimethylamino propylamine. Besides, it could be synthesised from other phenol derivative such as cresol, resorcinol and cardanol. In the same manner, we can use other polyamines such as ethylenediamine.

The method provided a simple and practical solution to reducing the cost of Mannich base hardener without significantly affecting the desired properties.

The method used to prepare Mannich‐based hardener was cost affective and could find numerous applications in protective coatings.

In recent years, efforts to develop alternatives to lead‐based solders have increased dramatically. These efforts began as a response to potential legislation and regulations restricting lead usage in the electronics industry. Lead is extremely toxic when inhaled or ingested. As researchers began to focus on Pb‐free solders, they recognized their value in high temperature applications (e.g. automotive manufacturing) where Sn/Pb solders do not meet the requirements. There are many factors to consider when developing lead‐free alloys: manufacturability, availability, reliability, cost and environmental safety. Of these, the most challenging and time consuming is the reliability of alternative solders. The lead‐free alloys available cannot be used as a drop‐in replacement for the SnPb or SnPbAg. The introduction of lead‐free solder alloys may mean having to use alternative component and PCB metallizations, PCB materials, solder fluxes, etc.

The purpose of this paper is to present the application of low temperature cofired ceramics (LTCC) technology in the fabrication of a novel electronic device, which consists of an antenna amplifier integrated with temperature stabilizer. The temperature controller consists of a thick‐film thermistor and heater, which has been optimized using geometry to achieve uniform temperature distribution on the whole electronic substrate.

LTCC technology was applied in the fabrication process of the novel device. The temperature distribution on the ceramic substrate and temperature stabilization time were analyzed using an IR camera. The heating ability of the heater was tested in a climatic chamber. The heater and thermistors parameters variability were estimated using a basic mathematical statistic.

The integrated device ensures proper temperature conditions of electronic components if the ambient temperature is lower than −40°C.

The presented device is just a first prototype. Therefore, the fabrication of the next structures and further experiments will be needed to improve structural drawbacks and to analyze precisely the device reliability and parameters repeatability.

The device presented in the paper can be applied in systems working at very low ambient temperatures (even at −5°C). Moreover, a temperature stabilizer can increase the temperature of the whole device above −40°C, therefore, standard electronic components (which can work down to −40°C) can be used instead of specialized ones (which can work below −40°C).

This paper presents a novel temperature stabilizer.

THE TERM “synthetic lubricant” has been adopted to designate a variety of fluids, derived from sources other than mineral oils, which have been developed by the technologist in order to satisfy the extreme conditions under which present‐day machinery has to operate : for example, high or low temperatures, or both, often with high bearing loads, and sometimes under conditions which demand resistance to ignition. Although, in fact, modern petroleum oils are prepared to such stringent specifications, and by such carefully controlled processes, that they are almost equally as “tailor‐made”, it is their comparatively limited temperature range that largely brought about the development of the so‐called synthetic product.