Hollow nickel selenide nanospheres coated in carbon as water oxygen electrocatalysts

2021 ◽  
Vol 305 ◽  
pp. 130748
Author(s):  
Pengkun Wei ◽  
Zewei Hao ◽  
Yang Yang ◽  
Lu Liu
Keyword(s):  
Water Oxygen

scholarly journals Assessing the predictability of existing water-to-enamel geolocation models against known human teeth

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Momoko Ueda ◽  
Lynne S. Bell
Keyword(s):  
Drinking Water ◽  
Stable Isotope ◽  
Stable Isotope Analysis ◽  
Isotope Analysis ◽  
Dental Enamel ◽  
Threshold Value ◽  
Human Teeth ◽  
Country Level ◽  
Water Oxygen ◽  
Human Enamel

AbstractStable isotope analysis of human tissues has become a valuable tool for mapping human geolocation. This study adds to the existing knowledge of the relationship between oxygen stable isotopes in human enamel and drinking water by presenting enamel oxygen values in clinic-extracted human dental enamel with known provenance. The results from this study indicate that the theoretical isotopic relationship between enamel and drinking water oxygen is weak at the city and country-level. Differences of up to 15‰ were observed between predicted drinking water oxygen values using existing models and observed values, highlighting the complexity of using water/enamel conversion equations. The lower isotopic boundary of enamel oxygen values is now understood for Metro Vancouver at δ18Oc(VPDB) = – 11.0‰ and presents the possibility of using stable isotope analysis as an exclusionary tool where individuals falling below threshold value can be identified as non-local. Overall, this study’s results support the development of geographical reference maps for human enamel oxygen.

New light on mechanism of air-water oxygen exchange in quiescent systems

1978 ◽  
Vol 12 (9) ◽  
pp. 649-654 ◽  
Author(s):  
T.J. Casey ◽  
P.E. O'Connor
Keyword(s):  
Oxygen Exchange ◽  
Water Oxygen

scholarly journals A seventy-two-year record of diminishing deep-water oxygen in the St. Lawrence estuary: The northwest Atlantic connection

2005 ◽  
Vol 50 (5) ◽  
pp. 1654-1666 ◽  
Author(s):  
Denis Gilbert ◽  
Bjorn Sundby ◽  
Charles Gobeil ◽  
Alfonso Mucci ◽  
Gilles-H. Tremblay
Keyword(s):  
Deep Water ◽  
Northwest Atlantic ◽  
Lawrence Estuary ◽  
Water Oxygen ◽  
St Lawrence Estuary

Respiratory responses to air-exposure in the southern rock lobster, Jasus edwardsii (Hutton) (Decapoda:Palinuridae)

1997 ◽  
Vol 48 (8) ◽  
pp. 889 ◽  
Author(s):  
H. Harry Taylor ◽  
Francesca M. Waldron
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Base Excess ◽  
Respiratory Acidosis ◽  
Metabolic Cost ◽  
Excess Oxygen ◽  
Air Exposure ◽  
Water Oxygen ◽  
Jasus Edwardsii ◽  
Resting Metabolism

Air-exposure of settled Jasus edwardsii at 17˚C initially halved oxygen consumption, doubled ventilation frequency and reduced heart rate. During 8 h emersion, oxygen uptake partially recovered, ventilation remained elevated and heart rate was restored. Haemolymph PCO2 increased fourfold, despite the hyperventilation. Branchial gas exchange, initially impaired in air, may improve as the gills drain. Partial anaerobiosis was indicated by elevation of haemolymph [lactate-] to 4.2 mmol L-1. Although haemolymph pH decreased ~0.3 units over 8 h, a base excess compensated all of the metabolic and part of the respiratory acidosis. On return to water, oxygen consumption initially increased to >2.5 times pre-emersion rates while ventilation and heart rates increased further. Most respiratory variables returned to pre-emersion levels within 8 h of re- immersion, but oxygen consumption and heart rate remained elevated for 24 h. The excess oxygen consumption over resting rate during 24 h recovery in water indicated a metabolic cost of 8 h emersion equivalent to 10 h resting metabolism in water. These responses contrast with better acid–base compensation previously reported for undisturbed Homarus gammarus in air and worse tolerance of air-exposure by Panulirus argus

scholarly journals Coastal hypoxia and sediment biogeochemistry

2009 ◽  
Vol 6 (7) ◽  
pp. 1273-1293 ◽  
Author(s):  
J. J. Middelburg ◽  
L. A. Levin
Keyword(s):  
Organic Matter ◽  
Bottom Water ◽  
Water Exchange ◽  
Transport Processes ◽  
Ecosystem Dynamics ◽  
Ecosystem Functions ◽  
Oxygen Levels ◽  
Concise Review ◽  
Water Oxygen ◽  
Sediment Biogeochemistry

Abstract. The intensity, duration and frequency of coastal hypoxia (oxygen concentration <63 μM) are increasing due to human alteration of coastal ecosystems and changes in oceanographic conditions due to global warming. Here we provide a concise review of the consequences of coastal hypoxia for sediment biogeochemistry. Changes in bottom-water oxygen levels have consequences for early diagenetic pathways (more anaerobic at expense of aerobic pathways), the efficiency of re-oxidation of reduced metabolites and the nature, direction and magnitude of sediment-water exchange fluxes. Hypoxia may also lead to more organic matter accumulation and burial and the organic matter eventually buried is also of higher quality, i.e. less degraded. Bottom-water oxygen levels also affect the organisms involved in organic matter processing with the contribution of metazoans decreasing as oxygen levels drop. Hypoxia has a significant effect on benthic animals with the consequences that ecosystem functions related to macrofauna such as bio-irrigation and bioturbation are significantly affected by hypoxia as well. Since many microbes and microbial-mediated biogeochemical processes depend on animal-induced transport processes (e.g. re-oxidation of particulate reduced sulphur and denitrification), there are indirect hypoxia effects on biogeochemistry via the benthos. Severe long-lasting hypoxia and anoxia may result in the accumulation of reduced compounds in sediments and elimination of macrobenthic communities with the consequences that biogeochemical properties during trajectories of decreasing and increasing oxygen may be different (hysteresis) with consequences for coastal ecosystem dynamics.

Bi-Functional Water/Oxygen Electrocatalyst Based on PdO-RuO2Composites

2012 ◽  
Vol 160 (1) ◽  
pp. H74-H79 ◽  
Author(s):  
Jaka Sunarso ◽  
Alexey M. Glushenkov ◽  
Angel A. J. Torriero ◽  
Patrick C. Howlett ◽  
Ying Chen ◽  
...  
Keyword(s):  
Water Oxygen
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