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Abstract Uncertainties in the temporal and spatial patterns of marine primary production and respiration limit our understanding of the ocean carbon (C) cycle and our ability to predict its response to environmental changes. Here we present a comprehensive time‐series analysis of plankton metabolism at the Hawaii Ocean Time‐series program site, Station ALOHA, in the North Pacific Subtropical Gyre. Vertical profiles of gross oxygen production (GOP) and community respiration (CR) were quantified using the18O‐labeled water method together with net changes in O2to Ar ratios during dawn to dusk in situ incubations. Rates of14C‐bicarbonate assimilation (14C‐based primary production [14C‐PP]) were also determined concurrently. During the observational period (April 2015 to July 2020), euphotic zone depth‐integrated (0–125 m) GOP and14C‐PP ranged from 35 to 134 mmol O2m−2d−1and 18 to 75 mmol C m−2d−1, respectively, while CR ranged from 37 to 187 mmol O2m−2d−1. All biological rates varied with depth and season, with seasonality most pronounced in the lower portion of the euphotic zone (75–125 m). The mean annual ratio of GOP to14C‐PP was 1.7 ± 0.1 mol O2(mol C)−1. While previous studies have reported convergence of GOP and14C‐PP with depth, we find a less pronounced vertical decline in the GOP to14C‐PP ratios, with GOP exceeding14C‐PP by 50% or more in the lower euphotic zone. Variability in CR was higher than for GOP, driving most of the variability in the balance between the two.
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Investigating the role of amine in InP nanocrystal synthesis: destabilizing cluster intermediates by Z-type ligand displacement
The reaction of primary amines with In 37 P 20 (O 2 CR) 51 is found to remove In(O 2 CR) 3 subunits from In 37 P 20 (O 2 CR) 51 . This loss of Z-type ligands coincides with structural rearrangement to alleviate core strain and passivate phosphorus atoms. This result consolidates conflicting claims that primary amines both promote and retard precursor conversion rates for InP nanocrystals.
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- Award ID(s):
- 1552164
- PAR ID:
- 10113642
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 53
- Issue:
- 1
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 161 to 164
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C6CC07952K
