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1.
The chromium (Cr) evaporation behavior of several different types of iron (Fe)-based AFA alloys and benchmark Cr2O3-forming Fe-based 310 and Ni-based 625 alloys was investigated for 500 h exposures at 800 °C to 900 °C in air with 10% H2O. The Cr evaporation rates from alumina-forming austenitic (AFA) alloys were ~5 to 35 times lower than that of the Cr2O3-forming alloys depending on alloy and temperature. The Cr evaporation behavior was correlated with extensive characterization of the chemistry and microstructure of the oxide scales, which also revealed a degree of quartz tube Si contamination during the test. Long-term oxidation kinetics were also assessed at 800 to 1000 °C for up to 10,000 h in air with 10% H2O to provide further guidance for SOFC BOP component alloy selection.  相似文献   
2.
Quantifying change after large habitat restoration efforts is critical to assessing the effort's success. After river restoration activities, fish abundance is expected to increase and also fluctuates naturally by season and with environmental conditions. A side‐looking hydroacoustic system was used to estimate fish abundance in the Penobscot River, ME, from 2010 to 2016 during predam (2010–2013) and postdam (2014–2016) removal years during nonice periods. Automated data processing enabled continuous abundance estimates from fish tracks. A threefold increase in mean fish abundance was recorded after dam removal. A fourfold increase in median fish abundance occurred in the fall relative to spring and summer of the same year, regardless of dam presence. Interannual fish abundance in every season monitored increased at least twofold after dam removal. We related variability in fish abundance to tide, discharge, temperature, diurnal cycle, daylength, moon phase, and restoration activities (focusing on dam presence). Daylength corresponding to the fall and summer was the most important indicator for higher fish abundance. Fish abundance was generally greatest in the fall during outgoing tides at night, with lesser peaks occurring during the month of June at night. Before dam removal, fish abundance peaked when water temperature was less than 9.25°C, at night, during outgoing tides. After dam removal, fish abundance peaked when daylength was less than 11.3 hr, at night, during outgoing tides, when water temperature was above 4.56°C and no full moon was present. Peak fish abundance occurred during only 0.02–2.3% of the total time sampled. The threefold increase in fish abundance recorded after dam removal was observed despite yearly stocking efforts of adult alewife increasing 24% in postdam removal years. Finally, parallel studies of fish presence in the Penobscot River were used to compare the utility of this method as an indicator of fish abundance in response to dam removal.  相似文献   
3.
Lund  Brady D.  Maurya  Sanjay Kumar 《Scientometrics》2020,125(3):2491-2504
Scientometrics - This study investigates a potential relationship between highly-cited scholarly papers and the number of citations received by other papers with which they share a journal issue....  相似文献   
4.
While nutrient loading has affected all levels of Lake Winnipeg’s ecology, its greatest influence has likely been on the microbial community. In addition to eutrophication, zebra mussels (Dreissena polymorpha) have recently invaded the ecosystem and threaten food web dynamics. Their filter-feeding predation and association with bacteria, specifically phototrophs, was investigated. A sampling trip to Lake Winnipeg in October 2017, focused on the isolation, enumeration, and identification of aerobic anoxygenic phototrophs in littoral water, sediment, and tissues of mussels. Gimli, Patricia, and Grand beaches, separated by >15 km across the South Basin, had similar bacterial counts when cultivated on rich organic, BG-11, purple non-sulphur, and K2TeO3-supplemented media. Culture-based enumeration on rich organic medium revealed 1.74% of heterotrophs from littoral waters were aerobic anoxygenic phototrophs, and represented 13.98% within sediments. In contrast, 0.48, 1.15, and 0.16% of cultured heterotrophs were aerobic anoxygenic phototrophs within zebra mussel gill, gut, and gonadal tissues, respectively. High-throughput sequencing of bacterial 16S V4 rDNA maintained similar trends in respective bivalve organs, where 0.22, 1.13, and 0.20% of total 16S genes belonged to these phototrophs. Several Sphingomonadaceae isolates were recovered from gut tissues, all with filamentous morphology large enough for predation. Bioaccumulation of metals was also studied in D. polymorpha. All tested associated aerobic anoxygenic phototrophs were capable of resisting the metalloid oxide tellurite. The consistent distribution of aerobic anoxygenic phototrophs within microbial communities across Lake Winnipeg, and their predominance in the gut tissues of zebra mussels suggested bacterial consumption by this invasive species.  相似文献   
5.
JOM - The use of titanium machine turnings has been identified as a possible ultralow-cost method to produce titanium powder. However, very little data are available on the viability of this...  相似文献   
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7.
Modern manufacturing requires flexible and autonomous systems for materials handling and transportation. For such applications, a succession of implemented mobile robots has been developed over the past seven years. In this paper, the questions of software and hardware architecture are discussed in light of experience gained so far. Also discussed are mobile robot projects that seem realistic over the next five to ten years.  相似文献   
8.
In 2012 Arian Foster, a running back for the Houston Texans of the National Football League (NFL), announced via Twitter that he is “officially a vegan now” (Foster, July 6, 2012). Foster's announcement precipitated a torrent of attention by many who worriedly debated the impact that his new diet may have on his on-field performance. In this article, we unravel the threads that have woven together a picture of who Foster is and what his decision to go vegan means. We argue that a close look at the media response reveals deeply held beliefs about masculinity, race, class, and place and the ways in which food serves in the constitution of subjectivity in the context of pro-football in Texas. We conduct a contextual discourse analysis of the popular and sports media coverage of Foster's diet using an intersectional framework to elaborate how normative masculinity is further nuanced by the meanings attributed to race, place, sexuality, sport, aggression, violence, health, and productivity.  相似文献   
9.
Multidisciplinary team (MDT) meetings are becoming the model of care for cancer patients worldwide. While MDTs have improved the quality of cancer care, the meetings impose substantial time pressure on the members, who generally attend several such MDTs. We describe Lung Cancer Assistant (LCA), a clinical decision support (CDS) prototype designed to assist the experts in the treatment selection decisions in the lung cancer MDTs. A novel feature of LCA is its ability to provide rule-based and probabilistic decision support within a single platform. The guideline-based CDS is based on clinical guideline rules, while the probabilistic CDS is based on a Bayesian network trained on the English Lung Cancer Audit Database (LUCADA). We assess rule-based and probabilistic recommendations based on their concordances with the treatments recorded in LUCADA. Our results reveal that the guideline rule-based recommendations perform well in simulating the recorded treatments with exact and partial concordance rates of 0.57 and 0.79, respectively. On the other hand, the exact and partial concordance rates achieved with probabilistic results are relatively poorer with 0.27 and 0.76. However, probabilistic decision support fulfils a complementary role in providing accurate survival estimations. Compared to recorded treatments, both CDS approaches promote higher resection rates and multimodality treatments.  相似文献   
10.
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