Hydrochemical regime of the Partizanskaya R. estuary, Nakhodka Bay, the Sea of Japan
2
Citation
6
Reference
10
Related Paper
Citation Trend
Keywords:
Seasonality
Cracks are inevitable in concrete structures, and the deterioration of concrete crack interfaces in intertidal zones is often accelerated due to seawater dry–wet cycles. This paper aims to analyze the morphology and deterioration of crack interfaces under seawater dry–wet cycles. First, concrete crack surface specimens were obtained through splitting tests. Then, the specimens were placed in seawater solutions of different concentrations to undergo seawater dry–wet cycles. Furthermore, three-dimensional (3D) laser surface profile scanning was performed on the specimens after 0, 10, 30, and 60 seawater dry–wet cycles. Finally, the changes in morphological parameters were analyzed and calculated to derive the effect patterns of seawater dry–wet cycles on the 3D morphology of concrete crack interfaces. The results showed that the crack surface deterioration of the specimens in clear water was only affected by the dry–wet cycles, while that in seawater was jointly affected by seawater erosion and dry–wet cycles. The crack surface deterioration of the specimens in seawater can be divided into two stages. In the first 10 seawater dry–wet cycles, the chemical products generated by seawater erosion played a dominant role. The 3D morphological parameters and 3D fractal dimension changes of the specimens in seawater showed opposite trends to those in clear water. From the 10th seawater dry–wet cycle, erosion and flaking by the dry–wet cycles were dominant. The changes in the 3D morphological parameters and 3D fractal dimension of the specimens in seawater were consistent with those in clear water. Moreover, higher seawater concentrations led to more significant trends in the crack surface 3D morphological parameter and 3D fractal dimension changes.
Artificial seawater
Cite
Citations (2)
Highly polished coupons (25 by 25 by 1.5 mm) sourced from the same steel sheet were continuously immersion-exposed either to natural coastal seawater or to seawater from the same source subjected to filtration and UV irradiation to eliminate microbiologically influenced corrosion as much as possible. This was continued for 943 days (2.6 years). Dissolved oxygen levels were very similar in both environments. On average the UV-treated seawater was 2°C warmer, but all coupons exposed to it showed less localized corrosion than those exposed to natural seawater. The typical topographical difference was about 60% as measured by surface roughness parameter Sa. Mass losses in UV-treated seawater were about 10% higher than in natural seawater, but after temperature correction were similar to natural seawater for the first year and tended to be lower subsequently. At all exposure periods the rusts in UV-treated seawater were less voluminous than the rusts in natural seawater. Eventually they also contained a higher proportion of magnetite.
Cite
Citations (24)
The multi-outlets were installed on the existing seawater exchange breakwater in order to improve seawater exchange rate at Jumunjin harbor. Physical and numerical model system were fulfilled for 4 cases to evaluate seawater exchange system which is able to discharge water remotely. The seawater circulation pattern and seawater exchange rate in the harbor were compared and analyzed. Consequently, total seawater exchange rate for CASE 1 was calculated 48% due to the dead zones which hinder seawater circulation in the harbor. Otherwise, the seawater exchange rates of CASE 2, CASE 3, and CASE 4 with the installation of the system were enhanced 19%, 15% and 17%, respectively compare to CASE 1.
Circulation (fluid dynamics)
Cite
Citations (2)
Under the water temperature that ranges between 28.6 and 29.5℃ and pH 8.2,the growth and survival of Hemifusus tuba juveniles [shells high(19.5±1.23) mm,weight(661.4±48.6) mg] at different salinity were studied.The goal is to find out the range of optimal survival salinity and optimal growth salinity to H.tuba juveniles by two-point method.The results show that the suitable survival salinity and optimal survival salinity are 17.7‰ 40.8‰ and 25.1‰ 35.9‰,and that the growth suitable salinity and growth optimal salinity were 17.5 39.9‰ and 27.8 33.2‰,respectively.In the range of growth optimal salinity,the average daily growth rate of shells and weight were 0.358 0.397 mm.d 1 and 44.64 49.09 mg.d 1,respectively.The survival rate and the average daily growth rate of shells fell obviously when the range of salinity optimal survival salinity was exceeded.Moreover,the tolerance of salinity by H.tuba Juvenile was related to the original environmental salinity.The survival rate was 84.0% in 72h when the juveniles were adapted for 20d in the salinity of 17.0‰ and then transported to the salinity of 14.0‰,and the survival rate was 96.0% when the juveniles were adapted for 20d in the salinity of then transported to the salinity of 45.0‰.However,the survival rates were 8.0% and zero in 72h when the juveniles were transported from the salinity of 30.5‰ to 14.0‰ and 45.0‰,respectively.Both the suitable range and the tolerance of salinity can be increased when the juvenile was domesticated in gradually changing conditions.
Temperature salinity diagrams
Cite
Citations (0)
Abstract Estuary is an exclusive system and have an important role but also have vulnerabilities that can threaten life in the estuary region, so it is necessary to have knowledge of estuarine boundaries so that conservation can be maintained. This study aims to analyze the boundaries of the Cimandiri Estuary and the Cisadane Estuary based on surface water salinity, and analyze the relationship of estuarine surface water salinity with rainfall, sea surface currents and tides in the Cimandiri Estuary and Cisadane Estuary. The variables used in this study are salinity, rainfall, sea surface currents, and tides. The research method use the Cimandiri Algorithm by processing OLI Landsat 8 Imagery in 2018 and 2019. The results of this study are estuary boundaries divided into 3 estuary boundary classes specifically Mexo-oligohaline (0.5-5 ‰), Mexo-mesohaline (5-18 ‰), and Mexo-polyhaline (18-30 ‰). Cimandiri’s salinity value is strongly affected by season, then by tides and last by the currents, it is because the Cimandiri Estuary has a deep waters. Meanwhile in the Cisadane Estuary, the salinity value is strongly influenced by season, then by the currents and tides, and also influenced by freshwater from land, it is because the Cisadane Estuary has a shallow water.
Cite
Citations (1)
Fresh water
Temperature salinity diagrams
Environmental factor
Cite
Citations (14)
Cite
Citations (10)
Temperature salinity diagrams
Cite
Citations (49)
Water multi-utilization pattern system is of great significance for seawater utilization and the reduction of waste seawater discharge of aquaculture. However, the change analysis of seawater quality in the water multi-utilization pattern system is little reported. The water multi-utilization pattern system of Cynoglossus semilaevis-Penaeus vannamei-Artemia-ocean chemical industry was employed to determine the changes of seawater quality. Results showed that with seawater utilized continuously, pH, inorganic N and P, organic N, total N and COD concentrations were all increased significantly(p0.05),which indicated that aqua-cultivation can lowering seawater quality significantly. Compared with continuous increase of organic N, total N and COD concentrations, inorganic N and P concentrations of seawater changed in the wave-shaped patterns,showing significantly higher than those of un-utilized seawater(p0.01). Wave-shaped patterns probably resulted from the organic N and P utilization by living beings in seawater. With seawater salinity increasing, the increase of organic N, total N and COD concentrations boosted greatly, which suggested that self-cleaning capacity of seawater was inhibited obviously.Compared with un-utilized seawater, organic N, total N and COD concentrations of seawater in Artemia cultivating pond increased by 6.27, 6.15 and 3.90 times respectively. Based on change rules of seawater, the seawater quality demands of components in water multi-utilization pattern systems should decrease in turn. At the same time, high efficient cultivating and cleaning technologies are also needed to improve seawater quality.
Artificial seawater
Cite
Citations (0)
The influences of the composition of seawater to the seawater direct electrolysis were discussed. The composition of seawater varies from season to season and from place to place. While the concentration of Cl~- decreases, the electrochemical potential in creases and the current efficiency decreases. The current efficiency increases progressively as the concentration of Mg~(2+) (or Ca~(2+)) concentration does.
Cite
Citations (0)