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High mortality rates have been observed when animals arc exposed for up to 100 min in r.f. radiation having frequencies greater than 10 MHz and power densities of the order of 100 mW/cm2. A safety level of 10 mW/cm2 for frequencies above 10 MHz and exposures of the order of 5 min has therefore been generally adopted. A continuously monitoring small-size instrument for dangerous maximum and average levels of microwave power is required, particularly if it can be carried in the pocket of a person in a similar manner as the well known X ray photographic monitor. 相似文献
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Despite the importance of river nutrient retention in regulating downstream water quality and the potential alterations to nutrient fluxes associated with climate‐induced changes in Arctic hydrology, current understanding of nutrient cycling in Arctic river systems is limited. This study adopted an experimental approach to quantify conceptual water source contributions (meltwater, groundwater), environmental conditions and uptake of NO3?, NH4+, PO43? and acetate at 12 headwater rivers in Svalbard and so determine the role of changing hydrology on nutrient uptake in these Arctic river systems. Most rivers exhibited low demand for NO3? and PO43?, but demand for NH4+ and acetate was more variable and in several rivers comparable with that measured in sub‐Arctic regions. The proportion of meltwater contributing to river flow was not significantly related to nutrient uptake. However, NH4+ uptake was associated positively with algal biomass, water temperature and transient storage area, whereas acetate uptake was associated positively with more stable river channels. Mean demand for NH4+ increased when added with acetate, suggesting NH4+ retention may be facilitated by labile dissolved organic carbon availability in these rivers. Consequently, nutrient export from Arctic river systems could be influenced in future by changes in hydrological and environmental process interactions associated with forecasted climate warming. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Mounting media for examining rubber reinforced copolymers using the phase microscope are described. The mounting media are based on cinnamaldehyde as the basic solvent with suitable adjustments made depending upon the copolymer under examination. 相似文献
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Joyce McLaren Nick Laws Kate Anderson Nick DiOrio Hannah Miller 《The Electricity Journal》2019,32(1):28-46
This paper explores the economics of solar-plus-storage projects for commercial-scale, behind-the-meter applications. It provides insight into the near-term and future solar-plus-storage market opportunities across the U.S. We explore the impacts of location, building load profile, technology cost, utility rate structure, and policies on solar-plus-storage economic viability, and identify which factors are most significant to project economics. While savings from storage-only projects are largely derived from demand charge reductions, solar combined with storage also provides significant energy charge savings. A common assumption is that load profiles with peaks are likely candidates for savings from storage, due to the opportunity for demand charge reduction. Our results indicate that potential for savings from combining solar with storage is independent of building load variability, likely due to the energy cost reductions from the solar. Systems are more often economical under time of use and demand charge rates, particularly when demand charges are >$10 per kilowatt. Where systems were found to be economical, expected lifetime savings averaged between 7%–10%, with savings of 30% in numerous cases. Near term markets exist for solar-plus-storage in locations such as California and New York. As technology prices drop, the number of building types that can benefit increase, and additional markets appear in Colorado, New Mexico, and Alaska. All data from the study and interactive modeling results are available at: https://openei.org/wiki/Solar+Storage. 相似文献
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The recent introduction of the Electric Power Research Institute (EPRI) single-phase Written Pole soft-start motor may open new possibilities and marketing opportunities for rural electric cooperatives. The new single-phase high-efficiency AC motor technology promises soft-start capabilities that allow designs and application of up to 60 hp 240 V motors. This paper summarizes some of the technical aspects of the new single-phase motor technology. An actual field test and application of a Written Pole motor is also be used to compare motor starting currents and line flicker with manufacturer's literature and specifications 相似文献
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Sreepradha Eswaran Anshu Babbar Hannah K. Drescher Thomas C. A. Hitch Thomas Clavel Moritz Muschaweck Thomas Ritz Daniela C. Kroy Christian Trautwein Norbert Wagner Angela Schippers 《International journal of molecular sciences》2021,22(14)
(1) Background: Non-alcoholic fatty liver disease (NAFLD) is a growing global health problem. NAFLD progression involves a complex interplay of imbalanced inflammatory cell populations and inflammatory signals such as reactive oxygen species and cytokines. These signals can derive from the liver itself but also from adipose tissue or be mediated via changes in the gut microbiome. We analyzed the effects of a simultaneous migration blockade caused by L-selectin-deficiency and an enhancement of the anti-oxidative stress response triggered by hepatocytic Kelch-like ECH-associated protein 1 (Keap1) deletion on NAFLD progression. (2) Methods: L-selectin-deficient mice (Lsel−/−Keap1flx/flx) and littermates with selective hepatic Keap1 deletion (Lsel−/−Keap1Δhepa) were compared in a 24-week Western-style diet (WD) model. (3) Results: Lsel−/−Keap1Δhepa mice exhibited increased expression of erythroid 2-related factor 2 (Nrf2) target genes in the liver, decreased body weight, reduced epidydimal white adipose tissue with decreased immune cell frequencies, and improved glucose response when compared to their Lsel−/−Keap1flx/flx littermates. Although WD feeding caused drastic changes in fecal microbiota profiles with decreased microbial diversity, no genotype-dependent shifts were observed. (4) Conclusions: Upregulation of the anti-oxidative stress response improves metabolic changes in L-selectin-deficient mice but does not prevent NAFLD progression and shifts in the gut microbiota. 相似文献