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排序方式: 共有496条查询结果,搜索用时 640 毫秒
71.
As power costs continue to rise, the world's exisiting motor population will become more and more obsolete. Today's astute textile manufacturing companies wiUl recognize this fact and seek ways of upgrading their machines. Two major alternatives available to these companies are reviewed: replacing motors before they fail, known as retrofitting, and replacing rather than rewinding motors as they fail with high-efficiency motors. Issues related to the alternatives discussed are 1) economics of motor replacement, 2) development of equipment list and data, 3) operating efficiency of existing motors, 4) impact of rewinding on efficiency, 5) verification of efficiency assumptions via on-site testing, 6) determination of changeout labor cost, 7) salvage value of exisiting motors, 8) downtime and its effect on replacement programs, 9) reliabilty enhancement, and 10) warranty implications. 相似文献
72.
Lesley A. Chesson Brett J. Tipple Brad R. Erkkila Thure E. Cerling James R. Ehleringer 《Food chemistry》2011
Stable isotope analysis is an established method for detecting honey adulteration. We extend its application to include honey and honeycomb region-of-origin assignment using hydrogen (δ2H) and oxygen (δ18O) isotopes. We observed that liquid honey δ2H and δ18O values had the potential to change because of water absorption and H atom exchange between sugars and water vapour. This suggested that liquid honey has limited use for geo-location, because specimens will record analysis location humidity. Paired liquid honey and honeycomb δ2H values were significantly correlated; therefore, we propose using wax δ2H values for region-of-origin assignment. We observed significant correlations between beeswax δ2H values and both mean annual precipitation and tap water δ2H values predicted for hive locations, suggesting that geographical variation in water δ2H values are recorded by beeswax δ2H values. This survey demonstrates the promise of stable isotopes for region-of-origin assignment, using honeycomb wax δ2H values, which complements carbon isotope analysis to detect adulteration. 相似文献
73.
Mariah J. Nondorf Yuan H. Brad Kim 《International Journal of Food Science & Technology》2022,57(5):3021-3030
The aim of this study was to determine the effects of tumbling at different post-mortem times on the proteolytic features and quality attributes of beef loins (M. longissimus lumborum). Loins (n = 12) were cut into 4 sections and assigned to tumbling at 1, 6 or 11 days post-mortem or non-tumbled control. Upon tumbling, additional ageing was applied to a common post-mortem time of 16 days. In general, tumbling had no considerable impacts on water-holding ability of samples. Tumbling resulted in an immediate decrease in shear force values (WBSF) of beef samples. Tumbling at 1 day post-mortem with no ageing had similar WBSF compared to the non-tumbled controls at 16 days (P > 0.05). With ageing, tumbling increased amounts of protein degradation, myofibrillar fragmentation and calpain-1 autolysis of samples. These results suggest that early post-mortem tumbling coupled with ageing can synergistically impact the tenderness development of beef loins and shorten the necessary ageing period. 相似文献
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Jan-Michael Hessenauer Cleyo Harris Stephen Marklevitz Matthew D. Faust Michael W. Thorn Brad Utrup Darryl Hondorp 《Journal of Great Lakes research》2021,47(2):475-485
The St. Clair-Detroit River System contains a world-class Great Lakes muskellunge (Esox masquinongy) fishery that has avoided the declines observed in many Great Lakes muskellunge populations. Muskellunge are an upper trophic level predator, and therefore a naturally low-density species. Limited fishery-independent data exist on which to base management decisions. To remedy this, we initiated an acoustic telemetry study in May of 2016, in collaboration with the Great Lakes Acoustic Telemetry Observation System. Our objective was to describe patterns of movement of muskellunge in this large and open system to better understand their spatial ecology. We acoustically tagged 133 muskellunge in the Detroit River and Lake St. Clair, and movements of 58 fish that passed our data quality control screens were analyzed. We utilized mixed modelling to assess the effects of sex, length, release location, and season on daily movement rates. We found that movement rates only differed among seasons, with highest movement rates occurring in the fall and lowest movement rates in the winter. Muskellunge tagged at different locations exhibited distinct residency patterns, and fish frequently crossed jurisdictional and waterbody boundaries. Ultimately our study highlights the scope and patterns of muskellunge movement in a large, unimpounded system and demonstrates that management of these fish would benefit from consideration of their full distribution covering multiple management jurisdictions. 相似文献
77.
Juliana M. Guedes-Oliveira Yuan H. Brad Kim Carlos A. Conte-Junior 《International Journal of Food Science & Technology》2021,56(12):6157-6170
In recent years, much attention has been paid to the consumption of meat and processed meat, and their relationship with a healthy diet. This review provides an overview of the potential strategies, which can be used to provide the implications for producing healthy, wholesome and consistently high-quality meat products. Genetic selection, nutrition and feeding management, and gene manipulation techniques have been used as the main strategies to induce beneficial changes in meat and meat composition. Besides, the incorporation of ingredients that play a technological role and are potentially health-enhancing, such as fibre, fat substitutes, natural antioxidants and the reduction of sodium and nitrites, has a high potential in the development of healthier meat products. In this review, we have observed that many strategies have been successfully used to obtain products with low fat, reduced sodium and nitrite content, low cholesterol and absence of synthetic antioxidants. Another point to be highlighted is that some of these strategies also allow obtaining products with positive health effects that can be potential alternatives to improve consumer acceptance. 相似文献
78.
The paper presents an improved context-based denoising method for gray scale images affected by impulse noise. The proposed algorithm is using Markov chains to replace the detected noise with the intensity having the highest number of occurrences in similar contexts. The context of a noisy pixel consists in its neighbor pixels and is searched in a larger but limited surrounding area. We have analyzed different search methods and different context shapes. The experimental results obtained on the test images have shown that the most efficient model applies the search in form of “*” of contexts in form of “+”. Besides the better denoising performance obtained on all the noise levels, the computational time has been also significantly improved with respect to our previous context-based filter which applied full search of full context. We have also compared this improved Markov filter with other denoising techniques existing in the literature, most of them being significantly outperformed. 相似文献
79.