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Food fraud, including the more defined subcategory of economically motivated adulteration, is a food risk that is gaining recognition and concern. Regardless of the cause of the food risk, adulteration of food is both an industry and a government responsibility. Food safety, food fraud, and food defense incidents can create adulteration of food with public health threats. Food fraud is an intentional act for economic gain, whereas a food safety incident is an unintentional act with unintentional harm, and a food defense incident is an intentional act with intentional harm. Economically motivated adulteration may be just that-economically motivated-but the food-related public health risks are often more risky than traditional food safety threats because the contaminants are unconventional. Current intervention systems are not designed to look for a near infinite number of potential contaminants. The authors developed the core concepts reported here following comprehensive research of articles and reports, expert elicitation, and an extensive peer review. The intent of this research paper is to provide a base reference document for defining food fraud-it focuses specifically on the public health threat-and to facilitate a shift in focus from intervention to prevention. This will subsequently provide a framework for future quantitative or innovative research. The fraud opportunity is deconstructed using the criminology and behavioral science applications of the crime triangle and the chemistry of the crime. The research provides a food risk matrix and identifies food fraud incident types. This project provides a starting point for future food science, food safety, and food defense research. PRACTICAL APPLICATION: Food fraud, including the more defined subcategory of economically motivated adulteration, is a food protection threat that has not been defined or holistically addressed. The terrorist attacks of September 11, 2001, led to the development of food defense as an autonomous area of study and a new food protection discipline. As economically motivated adulteration grows in scope, scale, and awareness, it is conceivable that food fraud will achieve the same status as an autonomous concept, between food safety and food defense. This research establishes a starting point for defining food fraud and identifying the public health risks. 相似文献
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The research and development effort in the field of solvent extraction of non-ferrous metals for the period from mid 1972 to late 1974 has been reviewed. As well as sections on such metals as copper, nickel-cobalt, uranium, rare earths, molybdenum, tungsten, vanadium, chromium, cadmium and zinc, sections on secondary metal wastes and on acid extraction have been included. The review shows that copper is still the main metal of interest for treatment by solvent extraction but also clearly shows the rising interest in the nickel-cobalt area. Indeed half the review is concerned with the copper, nickel-cobalt developments. The extension of the application of the technique into the field of secondary metal processing is a development of considerable interest. The large number of references (225) is indicative of the intensity of the research and development effort and this review should provide a quick and reliable source of reference for those wishing to keep abreast of this rapidly developing area of hydrometallurgy. This work was supported by the Chemicals and Minerals Requirements Board (Department of Industry). 相似文献
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The variation of fracture toughness with temperature and specimen size of a 3 pct NiCrMoV LP disc steel has been investigated
over the temperature range -100 to +100 °C using compact tension and single-edge-notched bend geometries. A number of large
‘half-disc’ three point bend specimens were also tested. Toughness increased up to a transition temperature coinciding with
the onset of stable ductile tearing prior to instability. Below this temperature fracture could be described by established
linear elastic or post yield fracture analyses. Above this temperature failure was by plastic collapse. The transition temperature
decreased with decreasing specimen size, and at similar thicknesses was lower for the bend geometry than for the compact tension
so that it was not possible to predict the fracture behavior of the full size service component from small scale tests in
the transition region. A further complicating feature was the extreme scatter of some duplicate test results below the transition
temperature. The implications for toughness testing in the transition region are discussed. The data obtained in this work
have been combined with published data for similar steels to derive an equation which describes the variation of fracture
toughness with temperature for steels of this type. 相似文献
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Tests performed on an inexpensive, low energy wet scrubber are described. The device employs a centrifugal fan, operated at 550–750 rpm, and co-current spray nozzles producing a relatively fine spray, from 20μ to 180μ. The fan acts as the prime mover of air, as contacting device, agglomerator, and precipitator. Variations in the scrubber's collection efficiency with changes in fan speed, water flow rate, nozzle position and with particle size in the range 0.1–3μ. have been studied. 相似文献
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Spink Kevin S.; Wilson Kathleen S.; Priebe Carly S. 《Canadian Metallurgical Quarterly》2010,14(2):163
This study examined the relationship between groupness and self-reported exercise adherence. Exercise participants (N = 86) recalled a structured setting where they had been active with others during the last six months. To capture groupness, five group variables (i.e., common fate, mutual benefit, social structure, group processes, and self-categorization) were assessed. Indicators of self-reported adherence were participant's recall of frequency (times/month) and percent attendance in a specified structured exercise setting. Results from structural equation modeling revealed an acceptable fit: χ2 = 18.89, p > .05, Root Mean Square Error of Approximation (RMSEA) = 0.075, Comparative Fit Index (CFI) = 0.95 for the hypothesized model. Groupness was positively related to self-reported adherence explaining 20% of the variance in adherence. These findings provide preliminary support for the idea that perceiving a collection of exercise participants as being more like a group may be associated with adherence in a structured exercise setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The development of digital libraries has enhanced the integration of textual and multimedia information in many document collections. The World Wide Web provides the connectivity for many digital library users. Studies exploring the searching characteristics of Web users are an important and a growing area of research. Most Web user studies have focused on general Web searching, regardless of subject matter or format. Little research has examined how Web users search for multimedia information. Our study examines users' multimedia searching on a major Web search service. The data set examined consisted of 1,025,908 queries from 211,058 users of Excite ®, a major Web search service. From this data set, we identified and analyzed queries for audio, image, and video queries. Our findings were compared to results from general Web searching studies. Implications for the design of Web searching services and interfaces are discussed. 相似文献
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