NUMERICAL AND LABORATORY EXPERIMENTS ON STABILITY OF GRANULAR FILTERS IN MARINE ENVIRONMENT

Although there are a great many experimental studies of particular pollutants and their effects, and some critical examination has been made of the mechanisms involved, there is great difficulty in determining whether such effects, if they are sublethal, occur in the sea. There is even more difficulty in deciding whether they produce significant harm in loss of organic production affecting, for example, the living resources of the sea: the stocks of fish and shellfish. Extrapolation from the results of laboratory experiments to the situation in the sea is hazardous because of the simplicity of experimental conditions in comparison with the complexity of the marine environment.

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Permeation Characteristics and Surface Accumulation of Chloride in Different Zones of Concrete along Altitude in Marine Environments

Crystals ◽

10.3390/cryst11070722 ◽

2021 ◽

Vol 11 (7) ◽

pp. 722

Author(s):

Hong Chang ◽

Zhicheng Zhang ◽

Zhanguo Ma ◽

Yongsheng Ji ◽

Xinshuo Huang

Keyword(s):

Marine Environment ◽

Moisture Transport ◽

Altitudinal Gradient ◽

Laboratory Experiments ◽

Convection Zone ◽

Bulk Liquid ◽

Splash Zone ◽

Tidal Zone ◽

Chloride Profiles ◽

Accumulation Characteristics

The accumulation characteristics of surface chloride in concrete in different zones are different in the marine environment. A series of laboratory experiments were conducted to investigate the surface chloride and permeation characteristics of concrete in a simulated marine environment. The experimental results indicated that the surface chloride and chloride profiles of concrete in different zones of marine environment decreased in the following order: tidal zone > splash zone > submerged zone > atmospheric zone. The width of the ascent zone of Cl− concentration at tidal and splash zones was far less than that of the influential depth of moisture transport (IDMT), and the range of convection zone was dependent on the IDMT. Cl− at splash and tidal zones penetrated into concrete as a bulk liquid by non-saturated permeation driven by a humidity gradient. The change of chloride profiles in concrete along the altitudinal gradient was consistent with that of the cyclic water absorption amount (CWAA). The transport rate of chloride was the highest at the highest point of the tide.

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Marine Oil Snow, a Microbial Perspective

Frontiers in Marine Science ◽

10.3389/fmars.2021.619484 ◽

2021 ◽

Vol 8 ◽

Author(s):

Benjamin H. Gregson ◽

Boyd A. McKew ◽

Robert D. Holland ◽

Timothy J. Nedwed ◽

Roger C. Prince ◽

...

Keyword(s):

Organic Matter ◽

Crude Oil ◽

Microbial Communities ◽

Marine Environment ◽

Laboratory Experiments ◽

Extracellular Polymeric Substances ◽

Marine Microbes ◽

Marine Oil ◽

Spilled Oil

Under certain conditions, dispersed crude oil in the sea combines with organisms, organic matter, and minerals to form marine oil snow (MOS), thereby contributing to the sinking of oil to the seafloor. Marine microbes are the main players in MOS formation, particularly via the production of extracellular polymeric substances. Distinct groups of microbes also consume the majority of the hydrocarbons during descent, leading to enrichment of the less bioavailable hydrocarbons and asphaltenes in the residue. Here we discuss the dynamics of microbial communities in MOS together with their impacts on MOS evolution. We explore the effects of dispersant application on MOS formation, and consider ways in which laboratory experiments investigating MOS formation can be more representative of the situation in the marine environment, which in turn will improve our understanding of the contribution of MOS to the fate of spilled oil.

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Partitioning of alcohol ethoxylates and polyethylene glycols in the marine environment: Field samplings vs laboratory experiments

The Science of The Total Environment ◽

10.1016/j.scitotenv.2014.05.061 ◽

2014 ◽

Vol 490 ◽

pp. 671-678 ◽

Cited By ~ 6

Author(s):

Juan M. Traverso-Soto ◽

Bruce J. Brownawell ◽

Eduardo González-Mazo ◽

Pablo A. Lara-Martín

Keyword(s):

Marine Environment ◽

Laboratory Experiments ◽

Alcohol Ethoxylates ◽

Polyethylene Glycols

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Covering of cometary nucleus by refractory crust and its evolution into asteroid-like body

International Astronomical Union Colloquium ◽

10.1017/s0252921100031675 ◽

1999 ◽

Vol 173 ◽

pp. 365-370

Author(s):

Kh.I. Ibadinov

Keyword(s):

Laboratory Experiments ◽

Cometary Nucleus ◽

Sublimation Rate ◽

Cometary Nuclei ◽

Short Period Comet ◽

Short Period ◽

Brightness Decrease ◽

Crust Thickness ◽

Ice Sublimation ◽

Period Comet

AbstractFrom the established dependence of the brightness decrease of a short-period comet dependence on the perihelion distance of its orbit it follows that part of the surface of these cometary nuclei gradually covers by a refractory crust. The results of cometary nucleus simulation show that at constant insolation energy the crust thickness is proportional to the square root of the insolation time and the ice sublimation rate is inversely proportional to the crust thickness. From laboratory experiments resulted the thermal regime, the gas productivity of the nucleus, covering of the nucleus by the crust, and the tempo of evolution of a short-period comet into the asteroid-like body studied.

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Petroleum in the Marine Environment

Chemical & Engineering News ◽

10.1021/cen-v058n033.p022 ◽

1980 ◽

Vol 58 (33) ◽

pp. 22

Keyword(s):

Marine Environment

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When Does Voice Have to be More Than Only Listening? Procedural Justice Effects as a Function of Confident Leadership

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000011 ◽

2010 ◽

Vol 9 (2) ◽

pp. 69-78 ◽

Cited By ~ 8

Author(s):

David De Cremer ◽

Maarten Wubben

Keyword(s):

Procedural Justice ◽

Interaction Effect ◽

Laboratory Experiments ◽

Negative Emotions

The present research examined how voice procedures and leader confidence affect participants’ negative emotions and willingness to withdraw. It was predicted that receiving voice would be valued out of instrumental concerns, but only when the enacting leader was high in confidence. Two laboratory experiments indeed showed an interaction between type of voice (pre-decisional vs. post-decisional) and leader’s confidence (low vs. high) on participants’ negative emotions and willingness to withdraw. In particular, post-decision voice only led to more negative responses than did pre-decision voice when the enacting leader was high in confidence. Negative emotions mediated this interaction effect of type of voice on willingness to withdraw. Implications for integrating the leadership and procedural justice literatures are discussed.

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