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With the increasing trends towards fineline circuitry, contamination has become a major cause of defects. This paper outlines the techniques used in conducting a Contamination Audit and in generating a Contamination Matrix, which is a map of the types of contamination and their relative levels within a facility. Using the Contamination Matrix contamination control measures can be targetted in the most effective manner to achieve yield improvements.

With the increasing trends towards fineline circuitry, contamination has become a major cause of defects. This paper outlines the techniques used in conducting a Contamination Audit and in generating a Contamination Matrix, which is a map of the types of contamination and their relative levels within a facility. Using the Contamination Matrix contamination control measures can be targetted in the most effective manner to achieve yield improvements.

The aim of this study is to establish a dynamic model of the filtration ratio. For the problem that the measured value of the filtration ratio is far less than the theoretical value in the actual hydraulic filtering system, the paper aims to find the relationship between the filtration ratio and the parameters of the hydraulic systems, such as the contamination level and the dirt-holding quantity of the filter.

The paper opted for the method of experimental analysis and simulation to determine the relationship between the filtration ratio and the parameters of the hydraulic system, and established a dynamic filtration ratio model.

The paper provides a preliminary model of dynamic filtration ratio, and the model shows that the filtration ratio is exponentially related to the contamination level and the dirt-holding quantity. Different filters have different influence coefficients. The filtering capacity for a certain particle size and the contamination level control of the filter for different hydraulic systems can be judged according to the dynamic balance equation of hydraulic systems.

The paper is useful in the selection of filters and in the precise control of the contamination level of the hydraulic system.

Despite the growing popularity of online secondhand platforms globally, there is a lack of studies exploring how consumers worldwide perceive contamination and the use of secondhand goods differently according to the culture. Based on the consumer contamination theory, this study aims to investigate the cultural differences of South Koreans and Americans by examining three variables (e.g. transaction type, ownership duration and physical attractiveness) related to consumers' perception of contamination and purchase intentions for a secondhand apparel item.

Data were collected from 422 US and South Korean female consumers who were assigned to an experimental scenario, and their secondhand purchase intentions and perceived contamination were compared through independent t-tests and moderated regression analyses.

Consumers' purchase intentions increased, and perceived contamination decreased when the transaction type was business-to-consumer (vs consumer-to-consumer), when the item had been owned for a shorter period of time and when the item was sold by an attractive seller. Such effect was more pronounced for South Korean consumers than the US consumers in the negative contamination contexts (i.e. transaction type, ownership duration), but not in the positive contamination context (i.e. attractiveness).

The findings of the study add to the literature on consumer contamination theory through an examination of several negative and positive contamination factors in retail contexts and highlight the role of culture as a critical moderator.

The aim of this study is to determine the variation of the different oil analysis instruments in terms of standard deviation and CV‐values, when measuring samples of fully formulated hydraulic and gear oils taken from working systems.

In this investigation, two different spectrometric techniques, inductively coupled plasma‐optical emission spectrometers (ICP‐OES) and rotating disk electrode‐optical emission spectrometers (RDE‐OES), have been studied to determine the instruments' precision of measurement and ability to measure the absolute level of contamination. The study was based on a series of measurements using artificial contamination mixed with oil.

The ICP has better precision of measurement of the two instruments, but cannot predict the absolute values of contamination when oil samples are only treated by organic solvent dilution if the samples include large or dense particles. It is therefore not too good, with the sample pre‐treatment method used, at detecting wear processes that produce dense/large particles, such as pitting failure. For instance, microwave‐assisted acid digestion could be used for sample pre‐treating to obtain accurate results in that case. It should, however, be able to detect wear mechanisms that produce small particles such as abrasive wear in any case. The ICP has a repeatability value of r=3 percent and a reproducibility value of R=12 percent for contamination levels of between 50 and 400 ppm and r=0.6  and R=2 ppm, respectively, at values below 50 ppm. The RDE cannot predict the absolute value of contamination if this includes large or dense particles if proper sample pre‐treatment is not used. It is therefore not good at detecting wear mechanisms that produces dense/large particles (if the oil samples are not pre‐treated properly) such as pitting but should be able to detect abrasive wear and similar processes that produce small particles in any case. The RDE's precision of measurement is not as good as the ICP, with a reproducibility variation of R=r=25 percent for contamination levels between 20 and 500 ppm and R=r=6 ppm for contamination level below 20 ppm.

Only the effects from lubricating oils are studied.

This study will significantly increase the industrial knowledge concerning measurement precision in particle contamination measurement systems.

No similar study is found.

During offshore pipe-lay, pipe lengths with anticorrosion coating are welded together, and, to facilitate the welding process, the ends of the pipe remain uncoated. A wide range of field joint coating (FJC) types is available for coating this bare section, functioning in conjunction with the pipeline cathodic protection system to provide an anti-corrosion system or package. This paper aims to relate to two-layer type heat shrink sleeves (2LHSS), which commonly are used for FJC of concrete-weighted offshore pipelines where the sleeve typically is over-coated with a solid or foam type polyurethane “infill”. Similar sleeves also are used sometimes in exposed conditions on lines without concrete over-coating. The maximum allowable soluble salt contamination prior to application of high-performance coating systems can vary, depending upon the coating type, but typically has been set at 20 mg/m2 (de la Fuente et al., 2006). The first layer of three-layer heat shrink sleeve (3LHSS) systems for pipeline FJC, liquid epoxy, falls into this category (ISO_21809-3:2008, 2008). In contrast, the 2LHSS system does not use a liquid epoxy first layer but relies instead on the bonding of a “mastic” layer directly to the pipe metal surface. The maximum acceptable concentration of salt contamination on prepared metal surfaces prior to the application of 2LHSS has been a subject of debate and was the focus of this study. International standards for FJC do not provide a maximum salt level. However, some companies have continued to specify low thresholds for the maximum allowable salt level for 2LHSS, which can result in expensive delays in production during offshore pipe-lay. In this study, salt contamination levels of up to 120 mg/m2 were found to have no effect on peeling performance after accelerated aging by hot water immersion. Furthermore, preparation for welding and the use of potable water during ultrasonic testing procedures prior to FJC, typically reduces the salt contamination level to below 50 mg/m2 providing a strong case for the deletion of salt contamination testing for 2LHSS.

The potential risk of failure of the coating due to poor surface cleanliness/contamination was assessed by testing the adhesion between the coating and the steel substrate to which the coating is adhering, following a period of hot water immersion. Compliance with ISO 21809-3 “Annex I” requires 28 days’ immersion at maximum operating temperature. For this study, to create a severe situation, the test rings were subjected to accelerated aging by water immersion at the HSS upper specified temperature of 65°C for more than twice the specified period (ISO_21809-3:2008, 2008). Two HSS were tested; one was widely used in applications where exposure to moderate mechanical stress is required, having a high shear strength type mastic “hybrid” adhesive containing a significant proportion of amorphous polypropylene blended with tackifiers and ethylene vinyl acetate (EVA), Andrenacci et al. (2009) referred to as “Type A”. The second, referred to as “Type B”, is widely used in applications where it is covered by a layer of “infill”, typically consisting of polyurethane foam or solid polyurethane elastomer, i.e. typical design methodology for concrete coated pipelines. “Type B” HSS had a more moderate strength traditional type mastic than “Type A” containing a significant percentage of butyl rubber with asphalt, activation agents and tackifying resins. To determine how to apply the salt contamination without causing flash rust, a mini-study was completed on the steel substrate. After numerous trials, it was found impossible to not to form visible rust on the pipe surface. The extent of rusting was minimised by heating the pipe immediately after the application of the salt solution.

High levels of sea salt on power tool prepared pipe surfaces were investigated by peel testing of 2LHSS after hot water immersion and compared against peel tests undertaken prior to hot water immersion. The test conditions were considered severe: salt contamination levels of up to 120 mg/m2 applied on power tool cleaned pipe surfaces that had been aged for one year without prior grit blasting. The accelerated ageing procedure had twice the specified (ISO_21809-3:2008, 2008) water immersion duration, and the test samples had exposed edges providing the possibility for moisture to creep under the coating. The test results showed that there were no noticeable deleterious effects on the performance of the two most commonly used FJCs, 2LHSS. Therefore, it was concluded that, as the level of salt contamination on prepared pipe surfaces after wet non-destructive testing typically is much lower than the levels tested in this study, pipe surfaces prepared for the application of 2LHSS type do not require specific additional measures to further reduce salt contamination, provided that care is taken to ensure that these conditions are maintained consistently during pipe laying operations.

The frequency of salt contamination testing of power tool cleaned surfaces prior to mastic type heat shrink sleeves can be minimised, and perhaps omitted entirely, provided the above criteria are satisfied.

A literature review revealed there was little published information on the testing of 2LHSS and nothing related to hot water immersion testing. Hence, the results of this investigation have provided useful industrial data regarding the effect of hot water ageing and the influence of surface salt contamination on field joint corrosion prevention capabilities.

Many cases of food poisoning originate in the domestic environment and can be associated with improper food handling and ineffective cleaning by consumers. These practices could lead to the introduction and spread of bacterial contamination in the kitchen and if not subsequently removed could present an infection risk. This study proposes investigating changes in levels of bacterial contamination at five key sites in ten domestic kitchens during a period of 24 hours.

Microbiological swabs were used to provide an aerobic colony count and an Enterobacteriacea count. A record was kept of cooking, cleaning and other activities within the kitchen.

Results showed that contamination levels varied during the day, peaking after meal preparation and generally falling overnight. There was also indirect evidence of cross contamination, particularly from hands to other surfaces. Sites such as the refrigerator handle, kettle handle and taps, which generally only come into contact with hands, show increases in the levels of contamination recorded. Levels of microbiological contamination were lower in vegetarian than non‐vegetarian households. A variety of data showed that non‐food preparation activities also take place in the kitchen. These could also introduce bacterial contamination into the kitchen and facilitate their spread.

The implications of these results are that the most important time for cleaning in the kitchen is immediately after food has been prepared, with attention focussing on high risk areas such as the work surface, chopping board, taps and other hand contact surfaces.

This paper seeks to reduce the lack of quantitative research by addressing diminution in value to non‐residential property resulting from environmental contamination.

This meta‐analysis extracts data from approximately a dozen peer‐reviewed articles and 100 case studies from real estate appraisers in the USA. A dataset containing 106 contaminated non‐residential observations is examined using Regression (OLS). Forward (stepwise) and backward selection was performed. The dependent variable included percentage loss and dollar amount. The independent variables were contamination type, US region, land use type, distance from the source (mostly contaminated subjects), passage of time, year, urban or rural, market conditions, litigation, and indemnification.

The model adjusted R squares range from 37 percent to 66 percent. Approximately a third of cases had no loss. This research used petroleum case studies as the reference category for comparison with other types of contamination. The following variables were statistically significant in all four models: Creosote/PCB and Other contamination. The following were significant in two models: Other land use, 30‐year mortgage rate, Rural location, TPH, Multiple contamination, TCE, Under‐remediation, and Mineral extraction region. Finally, the following variables were significant in one model at least at a 90 percent level of confidence: Heavy metals, Industrial Midwest region, and pre‐1995 sale.

Properties in the remediation phase show less of a loss in value. Selective case studies within the same period of the clean‐up cycle make the best comparables. The US regional location was less important.

This is the first empirical research using a meta‐analysis to study damage effects for non‐residential property affected by contamination.

Customers might become concerned about getting contaminated and adapt their behavior accordingly, which is of critical concern for service managers. The purpose of this paper is threefold. First, this paper synthesizes the extant body of research within psychology and marketing into an integrative framework that helps understand the current state of knowledge on contamination. Second, this review summarizes evidence-based managerial recommendations on how to deal with customers' contamination concerns. Third, this paper provides guidance for future research by proposing several ways in which those concerns might influence service management.

This paper conducts an integrative literature review of over 30 years of psychology and marketing research on contamination concerns.

The paper reviews physical and metaphysical contagion models, the situational cues that may activate customers' contamination concerns, the psychological mechanisms that underlie the relationship between contamination and customer outcomes and the individual characteristics that influence customer sensitivity to contamination cues. Moreover, this review identifies actions that service managers can take to prevent customers' contamination concerns. Finally, still much has to be learned about how organizations should deal with fear of contamination by the time a next pandemic breaks out.

This paper develops an integrative framework that serves as a structured knowledge map onto the contamination phenomenon and paves the way for future service research.

The purpose of this paper is to present the development and implementation of a system of test methods for determining the contamination level in cleaning baths and using this system for long‐term monitoring in printed circuit board (PCB) production.

A set of test methods was chosen that indicated the contamination of production cleaning baths in four chambers of an ultrasonic cleaning equipment filled with a commercial alkaline cleaner and isopropanol. By long‐term monitoring, the amount of mechanical impurities, residue‐on‐evaporation, pH and conductivity were measured. Depending on the contamination of the cleaning baths, the final contamination of PCB surfaces was predicted and the baths were replaced with fresh baths.

A novel system for testing and monitoring the contamination of cleaning baths was developed and implemented. The sustainable compliance with the specification was assured in PCB production, thus, the final PCB contamination achieved was under 1.5/1.2 μg NaCl/cm² as measured using the IPC‐TM‐650 test method. Quality requirements were fulfilled. This novel system was successfully integrated into the company's quality management system.

The set of test methods were used for an alkaline cleaner and isopropanol and for both a conventional solder and a lead‐free one. Because the course of bath contamination, monitored by the four test methods, was found to be proportional, further development should be focused on the issue – i.e. to determine if the “proportionality” would be universal for all types of PCB manufacturing.

The paper deals with a new approach for quality testing and assurance in PCB manufacturing. A set of test methods for monitoring contamination levels in production cleaning baths was implemented. This also supports process control and minimises the impact of cleaning processes on the environment (i.e. the production of waste from cleaning was reduced).