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191.
A study of the direct uptake by Artemia salina of phosphate ion from the medium and its incorporation into acid-soluble organic phosphorous compounds over a range of exposure time from 2 to 30 min, using 32PO4 ion, indicated that the phosphate ion was directly taken up and was rapidly incorporated into the energy-rich compounds, such as adenosine triphosphate (ATP), guanosine triphosphate (GTP), and adenosine diphosphate (ADP), which were separated by ion-exchange chromatography using Dowex-1, X2. Even after an exposure of 2 min, the sum of the radioactivity of nucleotide-fractions was 37.4% of that of the whole acid-soluble extract. The most rapid incorporation of 32P occurred into ATP, followed by GTP and ADP. The amount of 32P incorporated into each fraction increased with increased exposure, giving straight lines when the radioactivity of each fraction was plotted against the exposure time on a logarithmic scale. Almost no difference, however, was observed in the distribution rate of 32P into each fraction at 2, 5, 10 and 30 min. These results show that inorganic phosphate absorbed by A. salina is rapidly incorporated into the energy-rich nucleotides, and that a dynamic equilibrium is established among various acid-soluble phosphorous compounds even after very short periods of time.  相似文献   
192.
To better understand the detonation characteristics of ammonium nitrate (AN) and activated carbon (AC) mixtures, steel tube tests were carried out for AN/AC mixtures of various compositions and different forms of AN (powdered, prilled, phase stabilized and granular), and the detonation velocity was measured. The powdered AN/AC mixtures gave higher detonation velocities than the other AN forms. For all the AN/AC mixtures, the experimentally observed detonation velocities at each loading density were far below the theoretically predicted values calculated by the CHEETAH code based on thermohydrodynamics, exhibiting so-called non-ideal detonation. The lowest detonation velocity of powdered AN/AC mixtures was obtained as D=1.25 km/s for an AC content of 0.1 wt%. This was considered to be close to the critical condition for stable detonation.  相似文献   
193.
In 2008, a new basal neoceratopsian was discovered in the Tando beds (Albian) of Tando Basin in South Korea. It represents the first ceratopsian dinosaur in the Korean peninsula and is assigned to Koreaceratops hwaseongensis gen. et sp. nov. Autapomorphies of Koreaceratops include very tall neural spines over five times higher than the associated centra in the distal caudals, and a unique astragalus divided into two fossae by a prominent craniocaudal ridge on the proximal surface. A phylogenetic analysis indicates that Koreaceratops is positioned between Archaeoceratops and all more derived neoceratopsians, and the elongation of caudal neural spines was an important derived character in non-ceratopsid neoceratopsians. The very tall caudal neural spines in Koreaceratops, Montanoceratops, Udanoceratops, Protoceratops, and Bagaceratops appear to be homoplasious, suggesting an independent adaptation, possibly for swimming. Skeletal evidence suggests that obligate quadrupedalism occurred gradually in neoceratopsians progressing from bipedal through facultative quadrupedalism, to complete quadrupedalism in Coronosauria.  相似文献   
194.
Environmental Geochemistry and Health - This study discusses an estimate of the risk associated with the intake of soil contaminated by lead, based on the nature of the source, through a detailed...  相似文献   
195.
Biochar has the potential to amend degraded soil and improve crop yield. An experiment involving municipal sludge pyrolysis was carried out in a horizontal quartz reactor over the temperature range of 300–700 °C. The aim of this work was to investigate the influence of pyrolysis temperature on product distribution and biochar properties required for agronomic applications. Results of the experiment showed that yield and energy conversion efficiency of biochar decreased as pyrolysis temperatures rose, while bio-oil and syngas increased gradually. Biochar aromaticity barely changed, while polarity gradually decreased and specific surface area increased with a rise in pyrolysis temperature. Nutritive elements showed different enriching characteristics in the sludge pyrolysis process: nitrogen failed to enrich in biochars, whereas both phosphorus and potassium were enriched. Heavy metals showed good stability in the pyrolysis process except chromium; the contents of all metals used in the biochar conformed to Chinese control standards for agronomic application.  相似文献   
196.
Environmental Fluid Mechanics - The main objective of conducting numerical simulations of flows in rivers with vegetation is to investigate the complex flow dynamics involved in non-equilibrium...  相似文献   
197.
Journal of Material Cycles and Waste Management - To improve the recycling process of waste from electrical products, we developed a sensor-based sorting system using convolutional neural network...  相似文献   
198.
Environmental and Ecological Statistics - We propose a hierarchical log Gaussian Cox process (LGCP) for point patterns, where a set of points $$\varvec{x}$$ affects another set of points...  相似文献   
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