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531.
Lin YM Valdes-Garcia A Han SJ Farmer DB Meric I Sun Y Wu Y Dimitrakopoulos C Grill A Avouris P Jenkins KA 《Science (New York, N.Y.)》2011,332(6035):1294-1297
A wafer-scale graphene circuit was demonstrated in which all circuit components, including graphene field-effect transistor and inductors, were monolithically integrated on a single silicon carbide wafer. The integrated circuit operates as a broadband radio-frequency mixer at frequencies up to 10 gigahertz. These graphene circuits exhibit outstanding thermal stability with little reduction in performance (less than 1 decibel) between 300 and 400 kelvin. These results open up possibilities of achieving practical graphene technology with more complex functionality and performance. 相似文献
532.
Summary Effects of three rates of fertilizer nitrogen, viz. 80, 160 and 240 kg N/ha, on tuber yield and dry-matter percentage in potato
cv. Record were compared in two experiments. Crop nitrogen uptake increased with application rate but total uptake differed
between experiments. Tuber yield was highest following application of 160 or 240 kg N/ha but differences between these two
rates were not significant. Tuber dry-matter percentage was reduced in one experiment with increasing nitrogen rate, but in
the second experiment final dry- matter percentage was highest following application of 240 kg N/ha. In all treatments, positive
linear relationships were found between dry matter percentage and mean fresh weight of tubers >30 mm, but within experiments,
the regression coefficients were generally reduced by increased crop nitrogen uptake. 相似文献
533.
Geraldine V. Mitchell Mamie Young Jenkins Erich Grundel 《Plant foods for human nutrition (Dordrecht, Netherlands)》1989,39(1):53-58
As a part of a cooperative study initiated to assess bothin vitro andin vivo protein quality methods, the protein efficiency ratio (PER) and net protein ratios (NPR) of 15 different protein sources were determined. Male weanling Sprague-Dawley rats were fed a 10% protein diet. Fourteen-day NPR and relative NPR (RNPR) values and 14- and 28-day PER and relative PER (RPER) values were calculated for each protein source. When protein quality values were expressed relative to ANRC casein, the 14- and 28-day PER data ranked the protein sources essentially in the same order. RPER values of nonfat dried skim milk (unheated) and tuna were more than 100% that of casein; nonfat dried skim milk (heated), chickpeas, and breakfast sausage were between 50 and 70% of that of casein; and pinto beans and rice-wheat gluten cereal did not support substantial growth of the rat. The NPR method did not always rank the protein sources in the same order as the PER method. For the poor quality proteins, RNPR values were much higher than the RPER values; however, the RNPR and RPER values agreed closely for high quality protein sources.A preliminary report of this work was given at the Annual Meeting of the Federation of American Societies for Experimental Biology, Washington, D.C., March 29–April 2, 1987. Fed. Proc. 1987; 46: 889. 相似文献
534.
Bauder Javan M. Chandler Houston C. Elmore Michele L. Jenkins Christopher L. 《Landscape Ecology》2022,37(10):2519-2533
Landscape Ecology - Wildlife distributions are often subdivided into discrete conservation units to aid in implementing management and conservation objectives. Habitat suitability models,... 相似文献
535.
Bede?S.?MickanEmail author Lynette?K.?Abbott Jingwei?Fan Miranda?M.?Hart Kadambot?H.?M.?Siddique Zakaria?M.?Solaiman Sasha?N.?Jenkins 《Biology and Fertility of Soils》2018,54(1):55-70
Applications of compost and clay to ameliorate soil constraints such as water stress are potential management strategies for sandy agricultural soils. Water repellent sandy soils in rain-fed agricultural systems limit production and have negative environmental effects associated with leaching and soil erosion. The aim was to determine whether compost and clay amendments in a sandy agricultural soil influenced the rhizosphere microbiome of Trifolium subterraneum under differing water regimes. Soil was amended with compost (2% w/w), clay (5% w/w) and a combination of both, in a glasshouse experiment with well-watered and water-stressed (70 and 35% field capacity) treatments. Ion Torrent 16S rRNA sequencing and Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis of functional gene prediction were used to characterise the rhizosphere bacterial community and its functional component involved in nitrogen (N) cycling and soil carbon (C) degradation. Compost soil treatments increased the relative abundance of copiotrophic bacteria, decreased labile C and increased the abundance of recalcitrant C degrading genes. Predicted N cycling genes increased with the addition of clay (N2 fixation, nitrification, denitrification) and compost + clay (N2 fixation, denitrification) and decreased with compost (for denitrification) amendment. Water stress did not alter the relative abundance of phylum level taxa in the presence of compost, although copiotrophic Actinobacteria increased in relative abundance with addition of clay and with compost + clay. A significant role of compost and clay under water stress in influencing the composition of rhizosphere bacteria and their implications for N cycling and C degradation was demonstrated. 相似文献