Service life introduction

Over the past 25 years, the introduction of batteries described as maintenance-free (MF) has had an important impact on the SLI market. What this term implies in practice is that no addition of water to the electrolyte is required over a normal service life of 2-5 years. 

The addition of finely divided solids to rubber matrices is commonly practiced to increase the performance and service life of these materials. Indeed, without an active filler, a synthetic elastomer like Styrene Butadiene Rubber (SBR )would not be of much use. For instance, a tire made of pure vulcanized SBR would not last more than a few hundred miles. The introduction of coarse filler particles, such as milled quartz or clays, improves the situation so that the tire lasts thousands of miles. However, using active fillers like special grades of carbon black or silica has produced modem tires that operate satisfactorily for tens of thousands of miles. 

The appearance of premature and unexpected corrosion damage in reinforcedservice life in the 1970s. The service life of a structure can be defined as the period of time in which it is able to comply with the given requirements of safety, stability, serviceability and function, without requiring extraordinary costs of maintenance and repair [1,3,4]. 

As discussed in the introduction, reinforcement of elastomers can only be considered for a specific application, because it corresponds to an increase of product service life. Hence, in order to give some practical illustration of the different topics discussed earlier, we will present some results about carbon... 

Mechanization of loading in quarries started with the introduction of the cable-operated excavator, more particularly the face shovel, which is still on the market and available from many manufacturers and in many sizes. With its bucket fixed immovably to the arm, the diesel or electrically powered face shovel is purely a loading machine. Its relatively high capital cost can be justified by long service life, often twenty years or more. Larger machines generally last longer than smaller ones. 

The introduction of lead-calcium alloys started in the United States in the 1930s (37) and was specified for standby batteries in the Bell telephone service in 1951 (38). Corrosion of the lead-calcium alloy does not affect the electrochemistry of the battery, because calcium is not precipitated at the negative electrode but remains as Ca ion in the electrolyte. As a consequence, the hydrogen evolution rate is low and remains practically unaltered during the whole service life of the battery. 

Introduction. Electrochemical corrosion of the substrate may lead to a loss of joint strength and greatly reduce the service-life. However, one has to be wary of misinterpreting any initial observations of the failed joints often signs of gross corrosion are seen on the fracture surfaces of joints which have suffered environmental attack, but such corrosion may have frequently resulted after interfacial failure had occurred due to one of the mechanisms given in Section 2.2. Thus, in such cases, corrosion of the substrates is a post-failure event, rather than a primary cause of environmental failure. 

It should be emphasized that despite a MW increase, SSP also serves as a highly effident decontamination technique in PET bottle recyding industry. More specifically, decontamination is the removal of all possible alien chemical substances (contaminants) that have penetrated into botde wall through diffusion during the service life and waste disposal. This removal is an indispensable step in PET recycling because of (a) a variety of contaminants derived from the introduction of PET material to nearly all kinds of commonly used liquids, such as edible oil, household chemicals, detergents, and health-care products, and (b) the required... 

Besides already established technical polymers, the plastics industry is continuously developing new polymeric materials. Most of these produrts have to fulfill strict requirements during thdr service life depending on the individual applications. However, indispensable properties of plastic materials can only be achieved by optimal adjustment of the additives package to the spedfic requirements. Therefore, the development of tailor-made redpes and also the introduction of novel polymer additives and additive combinations contribute to strengthened and continuously improved plastic artides. 

Durability. Durability can be a useful way of improving eco-efiiciency. A product that has a long useful life minimises the impact per unit of service in the overall life cycle. However, there needs to be a balance, as a durable product with a poor environmental performance may block the introduction of a more eco-efficient technology. In many cases, governments have been driven to use fiscal incentives to encourage the adoption of a more environmentally friendly product because of the installed base of older but durable technologies. 

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