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91.
Toby J. Holda Lars G. Rudstam Kelly L. Bowen Brian C. Weidel James M. Watkins Patrick J. Sullivan Jeremy P. Holden Michael J. Connerton 《Journal of Great Lakes research》2019,45(2):307-316
Mysis diluviana is a major component of prey fish diets in the Great Lakes, so annual production of M. diluviana is important for understanding and modeling energy flow through Great Lakes food webs. However, only three lake-wide measurements of M. diluviana annual production in Lake Ontario are currently available (1971, 1990, 1995). During 2013, lake-wide coverage of Lake Ontario was achieved during four periods from April to November. Annual mean density and biomass of M. diluviana in 2013 were 99?#/m2 (SE: 8) and 318?mg?dw/m2 (SE: 28) – approximately half of values observed in 1990s. M. diluviana comprised 13–30% of offshore zooplankton biomass in each period. Reproduction peaked in fall, with mean brood size of 32 embryos (range: 11–49), at least 10% larger than in 1990s. Generation time was two years from embryo to initial reproduction. Growth rates were 0.052?mm/d for the age-0 cohort and 0.027?mm/d for the age-1 cohort. Age-0 growth rate was significantly higher than in 1980s–90s (0.035?mm/d). Annual production in 2013 was 0.85?g?dw/m2/yr (SE: 0.03) which was 30–40% of values observed in 1990 and 1995 (2.23 and 2.53?g/m2/yr). Annual production to biomass ratio (P/B) in 2013 was 2.65?/yr which was 80–85% of values observed in 1990 and 1995 (3.24 and 3.11?/yr), but this difference was not statistically significant. Our results suggest that changes in annual production over time can be estimated using changes in biomass over time and a mean P/B ratio. 相似文献
92.
93.
Amezhnov A. V. Rodionova I. G. Batsalev A. I. D’yakonov D. L. Shaposhnikov N. G. Shatskii T. E. Marzoeva M. E. 《Metallurgist》2019,62(9-10):1030-1038
Metallurgist - The effect of chemical composition and microstructure parameters on corrosion resistance of carbon and low-alloy steels in neutral aqueous media, typical for oil-field pipeline... 相似文献
94.
Nazin E. R. Zachinyaev G. M. Belova E. V. Emel’yanov A. S. Myasoedov B. F. 《Radiochemistry》2019,61(6):671-675
Radiochemistry - Thermal stability of hydrazine nitrate (HN) in solutions in 4–12 M HNO3 in the temperature interval 70–150°C was studied. Exothermic reactions accompanied by gas... 相似文献
95.
By using first-principles calculations we studied the electronic, optical and magnetic properties of ZnO co-doped with Eu and Pm. In this calculation, we used Wien2k code based on full potential linearized augmented plane waves (FP-LAPW) method with the modified Becke-Johnson (mBJ) approximation. This correction gives good band gap compared to experimental band gap. The introduction of Eu and Pm codoping leads to an increase in the band gap. Electrons can transit easily from the valence band to the conduction band, which results in an enhancement of visible light absorption in a wider absorption range. Absorption spectra reach a high value in visible and infrared light regions. With the significance of the obtained results, the studied compounds may potentially find spintronic and optoelectronic applications. 相似文献
96.
Refinement of atomic models is a necessary step in solving the macromolecular structure by X-ray diffraction methods. Nowadays, high automation and well-developed interfaces give a possibility to use the most popular refinement programs as black boxes. Nevertheless, working with complex objects requires an understanding of the internal structure and principles of operation of these programs and critical assessment of the results of refinement. In this review, we discuss the basic principles of the organization of refinement programs and the history of their improvement and development, as the studied objects became more and more complicated. The discussions are kept at the level of basic mathematic knowledge avoiding unnecessary formalism and too detailed expressions. 相似文献
97.
G. Inglese 《Inverse Problems in Science & Engineering》2019,27(4):439-459
We deal with the mathematical model of the incremental degradation of the internal coating (e.g. a polymeric material) of a metallic pipe in which a fluid flows relatively fast. The fluid drags solid impurities so that longitudinal scratches, inaccessible to any direct inspection procedure, are produced on the coating. Time evolution of this kind of defects can be reconstructed from the knowledge of a sequence of temperature maps of the external surface. The time-varying orthogonal section of this damaged interface is determined as a function of time and polar angle through the identification of a suitable effective heat transfer coefficient by means of Thin Plate Approximation. 相似文献
98.
Guzhov V. I. Il’inykh S. P. Pozdnyakov G. A. Khaidukov D. S. 《Optoelectronics, Instrumentation and Data Processing》2019,55(6):638-646
Optoelectronics, Instrumentation and Data Processing - A new method for image reconstruction from a series of digital holograms obtained by stepped phase shift with random values of phase shifts is... 相似文献
99.
Grigorenko G. M. Adeeva L. I. Tunik A. Yu. Korzhik V. N. Doroshenko L. K. Titkov Ye. P. Chaika A. A. 《Powder Metallurgy and Metal Ceramics》2019,58(5-6):312-322
Powder Metallurgy and Metal Ceramics - The structure and phase composition acquired by coatings deposited in optimum mode by the plasma arc spraying process were examined. The spraying materials... 相似文献
100.
Rebecca L. Tarnopol Sierra Bowden Kevin Hinkle Krithika Balakrishnan Akira Nishii Caleb J. Kaczmarek Tara Pawloski Dr. Anthony G. Vecchiarelli 《Chembiochem : a European journal of chemical biology》2019,20(20):2535-2545
One of the primary challenges facing synthetic biology is reconstituting a living system from its component parts. A particularly difficult landmark is reconstituting a self-organizing system that can undergo autonomous chromosome compaction, segregation, and cell division. Here, we discuss how the syn3.0 minimal genome can inform us of the core self-organizing principles of a living cell and how these self-organizing processes can be built from the bottom up. The review underscores the importance of fundamental biology in rebuilding life from its molecular constituents. 相似文献