In the process design and reuse of marine component products, there are a lot of heterogeneous models, causing the problem that the process knowledge and process design experience contained in them are difficult to ex...
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Phytoplankton communities in coastal upwelling systems are influenced by the interplay between human-induced and natural climate forcing that vary regionally and the two factors have not been well quantified. Combinin...
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The interplay among topology, crystal symmetry, magnetic order, and strong electron correlation can give rise to a plethora of exotic physical phenomena. The ZrSiS family is known as typical topological Dirac semimeta...
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The interplay among topology, crystal symmetry, magnetic order, and strong electron correlation can give rise to a plethora of exotic physical phenomena. The ZrSiS family is known as typical topological Dirac semimetals, among them LnSbTe (Ln denotes lanthanide) compounds exhibit intriguing characteristics due to the presence of Ln 4f electrons, resulting in quantum states and unique properties. In this paper, the topological electronic structure of PrSbTe is systematically studied by angle-resolved photoemission spectroscopy (ARPES), combined with magnetic, specific heat measurements, and band structure calculations. The detailed three-dimensional electronic structure of PrSbTe has been obtained, and a diamond-shaped Fermi surface and multiple Dirac nodal lines have been observed, which are in remarkable agreement with theoretical calculations. Moreover, the 4f electrons in PrSbTe are rather localized, which can be revealed by on-resonant ARPES data and further confirmed by the rather small Sommerfeld coefficient of γ=2.6231mJ/molK2. Our results provide more detailed information about the LnSbTe family, which gives a deeper understanding of the interaction between Ln 4f electrons and the topological states.
To utilize wave energy, we propose a power take-off device mainly composed of a novel buoy and a high-temperature superconducting synchronous reluctance linear generator (HTS-SRLG). We describe the conceptual structur...
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To utilize wave energy, we propose a power take-off device mainly composed of a novel buoy and a high-temperature superconducting synchronous reluctance linear generator (HTS-SRLG). We describe the conceptual structure and function of the buoy, which makes use of seawater to provide more power to the HTS-SRLG. Then, we introduce the configuration and the key electrical design process of the HTS-SRLG. Design result of the HTS-SRLG is presented and compared with that of counterparts to demonstrate its advantages in performance and in application. This article is conducted from the viewpoint of promoting the industrial application of HTS machines. The proposed buoy gives an insight of improving the utilizing efficiency of wave energy. And the HTS-SRLG contributes to simplify the generator cooling.
Anaerobic ammonium oxidation (anammox), an important process for converting fixed nitrogen to N-2, plays an important role in the present-day marine nitrogen cycle. However, little is known about anammox activities in...
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Anaerobic ammonium oxidation (anammox), an important process for converting fixed nitrogen to N-2, plays an important role in the present-day marine nitrogen cycle. However, little is known about anammox activities in the past, especially in regions that were strongly affected by human activities, evidenced by eutrophication and hypoxia, which promote anammox bacteria growth. In this study, ladderanes have been measured in a sediment core and suspended particulate matter (SPM) in the East China Sea (ECS), to reconstruct the anammox record and to evaluate its responses to eutrophication and hypoxia. The detection and distribution of different ladderane lipids in SPM provide additional evidence that ladderanes were mostly produced in the water column and could reflect anammox activities. Summed ladderane content from the core varied between 11 and 300 ng/g dry weight (dw) sediment, with C20-[5]-ladderane fatty acid methyl esters (FAME) as the predominant compound (5-150 ng/g dw), followed by C20-[3]-ladderane FAME (1-110 ng/g dw), C18-[3]-ladderane FAME (1-32 ng/g dw) and 08 -[5]-ladderane FAME (3-11 ng/g dw). The detection of ladderanes over the last century indicate the existence of anammox in the past. The rapidly increasing trend of ladderanes since the 1960s correlates with an increase in phytoplankton biomarkers (2 Sigma(B + D + A), brassicasterol (B), dinosterol (D) and C-37 alkenones (A)), indicating that eutrophication exacerbated anammox growth. The co-variation between our ladderane record and published records of low-oxygen tolerant foraminiferal microfossils and hypoxia events over the past 60 years suggested that sediment ladderanes are a useful indicator for past changes of oxygen depletion or hypoxia in the ECS. (C) 2019 Elsevier Ltd. All rights reserved.
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