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Deposition and accumulation of marine aerosol and its penetration into concretes exposed to the marine atmospheric zone: an overview

Yuan Qiang, Zhang Jiajia, Huang Zhibin, Zhang Zhipeng, Wang Xiongbiao, Li Binbin

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e65, 2023

EN

Marine aerosol, containing an enormous source of chloride, coupled with severe environmental conditions (e.g., high temperature, high relative humidity), poses a threat to the durability of concrete exposed to the marine atmospheric zone. The distribution of marine aerosol is spatial and temporal dependent, and thus, the deposition rate of airborne chlorides Ddep can vary a lot with geological and environmental factors. Chloride profile in concrete exposed to marine aerosol is a two-zone profile due to the wetting/drying action. The peak chloride concentration Cmax and depth of the convection zone Δx are largely affected by time, materials, environmental conditions which usually is less than 10 mm. Many models based on Fick’s law are developed to predict chloride transport in unsaturated concrete under wetting-drying cycles. However, the prediction of marine aerosol penetration into concrete is far from satisfactory, due to lack of enough experimental and theoretical researches.

2

Salinisation process of Lake Sidi Boughaba, Kenitra, North Western, Morocco: A statistical approach

Lachhab Mohamed, Najy Mohamed, Talbi Fatima Zahra, Taouraout Aziz, El Qryefy Mohamed, Ech-Chafay Hassan, Belghyti Driss, El Kharrim Khadija

Journal of Water and Land Development

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2022

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no. 54

194--200

EN

In order to determine the nature of the high salinisation rate of the waters of Lake Sidi Boughaba, which has been listed in the Ramsar list since 1980, 23 samples that were taken during four sampling operations were subjected to physicochemical analyses. The obtained results were processed using a combination of bi-varied methods (correlation tests) and multivariate statistical methods (principal component analysis - PCA). The physicochemical analyses reveal that they are alkaline waters with a pH ranging between 8.38 and 9.03, an electrical conductivity (EC) of the order of 12.4 to 17.4 mS∙cm-1, and high levels of Na+ and Cl-, up to 3700 and 6630 mg∙dm-3 respectively, indicating a marine origin of these waters. In addition, the statistical treatment revealed that the mineralisation of the waters of this ecosystem is controlled by four main mechanisms of the salinisation; the main mechanism underlying this strong mineralisation is due to the impact of the marine spray. The second-order processes are about the phenomenon of the ion exchange, the dissolution/precipitation of evaporitic and carbonate formations, the oxidation-reduction processes, notably the reduction of sulphates as well as biochemical phenomena due to the selective absorption of certain ions by fauna and flora.

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Variations in the physical properties of surf generated aerosols with altitude

Zieliński T.

Oceanologia

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2003

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No. 45 (4)

643-653

EN

Vertical profiles of marine aerosol size distribution and concentration in the marine boundary layer over surf zones depend strongly on wind speed, direction and duration as well as the sea bottom profile. The measurements in the present study were carried out in various seasons of the year with all these factors being taken into consideration. The data with respect to offshore winds were neglected in the calculations, since in such cases the major aerosol contribution was from terrigenous and anthropogenic particles. It was confirmed that in the range of wind speeds from 1 m s-1 to 12 m s-1 there were measurable differences in the concentrations, particularly in the size distribution of marine aerosol particles at two stations differing with respect to their sea bottom profiles.

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The effects of the marine aerosol on infrared propagation over the World Ocean

Gathman S. G.

Oceanologia

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1999

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No. 41 (4)

489-513

EN

In the modern world, where infrared systems are operated by the world's navies, it is important to understand the effect that large marine aerosols have on the propagation of these signals. This article reviews some of the work that has taken place to describe these aerosols and their scattering and absorption of infrared wavelength radiation. The paper describes those aerosols found in the marine environment which are produced by the whitewater phenomenon over the ocean, such as jet drops from breaking air bubbles at the sea surface and the shearing away of large droplets from cresting waves. These processes are the result of cresting of ocean waves and the breaking of swell and waves on the shore and are referred to as "open ocean phenomena" and "coastal processes". The paper also presents some of the early results of the United States coastal aerosol research project, EOPACE (Electro Optics Propagation Assessment in the Coastal Environment).

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Rozkłady rozmiarów aerozoli morskich nad morzami europejskiej Arktyki

Petelski T.

Problemy Klimatologii Polarnej

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1998

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nr 8

125—135

EN

Oceania in years 1995-1997. Sizes distribution were measured with an optical technique by laser particle counter. The size spectral density was found as a function n(r) = exp(ar + b), where: a = -0.249 and b is a function of wind velocity. According to data from 1995 b was b = 0.29U10 + 11.93 and according data to from 1996/1997 b was b = 0.19U10 + 11.63 were U10 wind velocity at 10m above sea level.