Part Of Seawater Research Articles

Cloud and IoT based smart architecture for desalination water treatment

Increasing water demand and the deteriorating environment has continuously stressed the requirement for new technology and methods to attain optimized use of resources and desalination management, converting seawater into pure drinking water. In this age, the Internet of Things use allows us to optimize a series of previously complicated processes to perform and required enormous resources. One of these is optimizing the management of water treatment. This research presents an implementable water treatment model and suggests smart environment that can control water treatment plants. The proposed system gathers data and analysing to provide the most efficient approach for water desalination operations. The desalination framework integrates smart enabling technologies such as Cloud Portal, Network communication, Internet of Things, Sensors powered by solar energy with ancient water purification as part of seawater's desalination project. The proposed framework incorporates the new-age technologies, which are essential for efficient and effective operations of desalination systems. The implemented desalination dual membrane framework uses solar energy for purifying saline water using ancient methods to produce clean water for drinking and irrigation. The desalination produced 0.47 m3/l of freshwater from a saline concentration of 10 g/l, consuming 8.31 KWh/m3 energy for production from the prototype implementation, which makes desalination process cost effective.

The influence of the marine environment on the properties of clothestextile materials for clothing

The article presents data on the influence of the marine environment on textile materials. Aggressive components of the marine environment that contact the surface of clothing (sea salt and oil) are justified. Sea salt is an integral part of seawater. It accumulates in the clothing structure. Oil is included in the components of seawater in emergency situations at offshore oil and petroleum products and sea transport facilities. This leads to a change in the properties of textile materials, which depend on the concentration of aggressive components in the structure of textile materials. The active concentration of aggressive components in textiles is determined by its ability to absorb liquid. Specific features of changing the volume of various textile fibers during interaction with liquids are established. Structure of sea salt and the chemical composition of oil. This determines the change in the properties of the textile in contact with them. The structure of sea salt and the chemical composition of oil is justified. This determines the change in the properties of textiles. As a result of the systematization of modern data on clothing materials that are used in marine technology, the information base of the leading modern fibrous materials for protective clothing was formed. The reference materials for research are allocated. It was found that the presence of sea salt in a moist contact medium with a surface of a special fabric on a cotton basis for all samples of materials led to a decrease in their capillarity. It has been established that packages of materials based on mixed-fiber fabrics have permeability parameters with respect to crude oil below the cotton garment surfaces. The application in combination with such materials of holofiber insulation reduces the level of saturation of clothing with the liquids examined. The article presents experimental data on the permeability of sea water and oil in special materials for clothing. The work was supported by the Ministry of Education and Science of Russia in the Don State Technical University within the framework of the State task 2017-2019 under the project No. 11.9194.2017/БЧ.

Effect of Aggressive Components of the Marine Environment the Protective Properties of the Textile Materials

The article provides the details on the influence of marine environment on textile materials. It justifies the aggressive components of marine environment in contact with clothing surface: sea salt and oil. Sea salt is an integral part of sea water and accumulates in the structure of clothing. Oil becomes a part of sea water in contingency situations at offshore oil and oil products production and transportation facilities. This causes a variation of the properties of textile materials that depend on the concentration of aggressive components in the structure of textile materials. Active concentration of aggressive components in the textile is defined based on its liquid absorption capacity. The article establishes the peculiarities of volume variation for different textile fibers interfacing with liquids. It identifies the structure of sea salt and chemical composition of oil that cause a variation of the properties of textile in contact with them. It was established that the presence of sea salt in humid environment contacting with the surface of special cotton based fabric causes reduction of capillarity in all material samples. It was established that the packages of materials based on fabrics with mixed fibers have crude oil permeation less than cotton surfaces of clothing. Meanwhile, use of thermal insulation, like Hollofiber together with such materials, reduces the level of clothing saturation with subject liquids. The article presents experimentally obtained data on sea water and oil permeation into special clothing materials.

A novel method of synthesizing solid phase adsorbent silica modified with xylenol orange: application for separation, pre-concentration and determination of uranium in calcium rich hydro-geochemical samples and sea water—Part 1

A novel, single-step route has been developed for the synthesis of solid phase adsorbent silica modified with xylenol orange. The addition of cationic surfactant cetyl tri-methylammonium bromide during the synthesis of the adsorbent supports the formation of a stable coating of xylenol orange on silica. The adsorbent showed no signs of degradation in contact with organic solvents and with solutions of varying pH between 1 and 9. This adsorbent has been used for separation and pre-concentration of uranium from hydro-geochemical samples with high calcium content and from sea water. Quantitative sorption of uranium was observed above pH 3 and complete desorption can be achieved using 0.2 M sodium pyrophosphate solution. The uranium content in the extract was determined by laser fluorimetric technique. The equilibration time is 30 min. The sorption capacity of the adsorbent for uranium is 10 mg g−1. An enrichment factor of 50 was obtained by this procedure taking 500 mL of sample solution. Uranium concentrations down to 0.05 ng mL−1 can be determined after pre-concentration using this method. The relative standard deviation at an 0.1 ng mL−1 level is ±15%.

Deleterious effects of water-soluble fraction of petroleum, diesel and gasoline on marine pejerrey Odontesthes argentinensis larvae

Accidental discharges and oil spills are frequent around the world. Petroleum-derived hydrocarbons are considered one of the main pollutants of aquatic ecosystem. The importance of petroleum and refined fuels is notorious because today's society depends on them. Researches related to the toxic water-soluble fraction (WSF) of petroleum and derivatives to aquatic biota are scarce. For this reason, deleterious effects of WSF of Brazilian petroleum, automotive diesel and unleaded gasoline to marine pejerrey Odontesthes argentinensis larvae were studied employing toxicity tests and histopathological examination. Each WSF was generated in a laboratory by mixing four parts of seawater with one part of pollutant by approximately 22 h. Larvae were exposed during 96 h to different concentrations of WSF of petroleum, diesel, and gasoline, plus a control. After 96 h of exposure to the different WSFs, three larvae were sampled for histopathological studies. The median lethal concentration after 96 h (LC50) of exposure for WSF of petroleum was equal to 70.68%, it was significantly higher ( P < 0.05) than the values for WSF of diesel and gasoline, which were 13.46% and 5.48%, respectively. The histological examination of pejerrey larvae exposed to WSF of petroleum, diesel and gasoline after 96 h revealed a variety of lesions in the larvae. The gills, pseudobranchs and esophagus presented epithelial hyperplasia, and the liver presented dilatation of hepatic sinusoids, hepatocitomegaly, bi-nucleated and nuclear degeneration of hepatocytes, such as pyknotic nuclei. The acute toxicity of diesel and gasoline is at least fivefold higher than Brazilian petroleum. However, all toxicants induced histopathological abnormalities in pejerrey larvae. The results are of importance since much attention has been paid to large visible surfaces of petroleum spills instead of potential toxic effects of dissolved aromatic hydrocarbons, which are more available to marine biota.

Killing of Red Tide Organisms in Sea Enclosure Using Hydroxyl Radical-Based Micro-Gap Discharge

A pilot-scale experiment for killing red tide organisms in a sea enclosure was done in Bohai Sea off Dalian City, China, in August 2003. With the physical method of micro-gap gas discharge, an OHmiddot solution of 24.3 mg/L was produced by the ionization of O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> in air and H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O at gas state and then dissolved into one part of seawater. When the OHmiddot concentration was 0.68 mg/L in the sea enclosure, the total kill efficiencies of 26 kinds of red tide organisms reached 99.8%, in which the bacterium and vibrio were reduced below the detection limit, meanwhile Gonyaulax cysts and Prei. Cysts with the cell crust were decreased to under the test limit. In addition, the content of chlorophyll-a was decreased below the test limit. The dissolved oxygen saturation of seawater was greatly increased to 430%. Therefore, the treatment of red tide using OHmiddot radicals is a kind of advanced oxidation technology, which realizes zero pollution, zero emission, and zero residual

Deep water STD at the Misima gold and silver mine, Papua, New Guinea

>The Misima Mine is the pioneer of deep‐water submarine tailings disposal (STD) and discharges at 112‐m depth, well below the zone of major biological productivity (euphotic zone), onto a steep seafloor slope that leads directly to a deep ocean basin. The system discharges approximately 18,000 tonnes of tailings solids per day and has a mix tank with seawater intake from 82‐m depth. Prior to discharge, each tailings part is diluted with approximately seven parts of seawater. Two validation surveys have shown that the system complies with regulatory conditions and meets ambient standards for contaminants well within a submerged mixing zone that extends to 1200‐m radius from the mix tank location. Video records obtained by remotely operated vehicle (ROV) show the tailings slurry descending the steep slope as a coherent bottom‐attached density current to at least the limit of the ROV tether at 160‐m depth. Geophysical survey and ocean floor sediment sampling has confirmed that accumulation of tailings solids...

Light-induced alteration of the photophysical properties of dissolved organic matter in seawater Part I. Photoreversible properties of natural water fluorescence

Fluorescence of humic substances changes when these substances are exposed to an ultraviolet monochromatic light source. Flourescence decreased with time of exposure when the irradiation took place at wavelengths of 334.1, 366 and 404.5 nm and increased with time at wavelengths of 265.2, 280.4, 296.7 and 313 nm. In addition, the process involved appeared to be partially photoreversible. The fluorescence decay resulting from irradiation at one of the longer wavelength bands could recover when followed by an irradiation interval at one of the shorter wavelength bands. In contrast, with polychromatic sunlight irradiation, only decreases in fluorescence were observed. Although the actual nature of the chromophores responsible for these fluorescence processes is still unknown, the results of this work suggest that the chromophoric unit responsible for the observed changes exists in both marine and terrestrial materials.

Acid-iron waste disposal and the summer distribution of standing crops in the New York bight

Ecological consequences arising from the disposal of 50 million tons of acid-iron industrial waste in the coastal waters off New York over the past 22 yr were assessed. Most of the data were obtained at two identical grids of stations which enabled comparisons of hydrographic, chemical and biological conditions within the acid-iron disposal area with similar parameters in a nearby control area. Supplementary information on benthos and sediment was obtained at other locations peripheral to the two station grids and in Hudson Gorge, and these were used to construct a synoptic picture of the physio—chemical conditions and standing crops in the New York Bight.At each grid station the hydrographic measurements made were temperature, salinity and light penetration; chemical observations consisted of dissolved oxygen, dissolved and suspended iron, total inorganic nitrogen and phosphate; while chlorophyll α, zooplankton and benthos biomass provided a measure of the abundance of standing crops. Trace metal spectra (Fe, Zn, Co, Cu, Pb, Cr, Ni and Cd) were determined on selected zooplankton, benthos and sediment samples. Laboratory toxicity studies were conducted on phytoplankton and zooplankton species at several concentrations of acid-iron waste in seawater.The maximum concentration of iron in the water column (832 μg 1−1) occurred as suspended material within a restricted area of the acid grid. In terms of raw acid-iron effluent this suggests a maximum in situ concentration of 1 part waste in 39,000 parts of seawater thereby providing a useful guide for the design of laboratory toxicity studies. Despite the abundance of suspended iron in the overlying water of the acid-grid the average concentrations of iron in the sediments of both the acid and control grids were remarkably similar, while sediments from the nearby Hudson Gorge were notably richer in iron. However, a comparison of previous measurements in the study area dating back to 1948 indicates that there has been no accumulation of iron within the sediments below the disposal area or Hudson Gorge over the past 22 yr.The phytoplankton toxicity experiment conducted with an acid-iron waste concentration four times greater than that observed in the field showed no adverse effect on phytoplankton growth or diversity. Similar experiments with copepods caused either failure of these organisms to reproduce or a delay in the time required to transform eggs into adults.Although the average zooplankton abundance within the control grid exceeded that of the acid grid by about 30 per cent, the range of values describing zooplankton abundance in the two areas was similar. This difference was attributed to a transitory large scale patchiness in the area and not to toxicity of acid-iron waste. A positive correlation was found between Fe:C in zooplankton and the amount of particulate iron present in the seawater.The average number of benthic animals on the bottom of the acid grid area was significantly less than in the sediment of the control grid but there was no difference in biomass or species diversity between the two areas. As was the case with zooplankton the higher Fe:C in the benthos corresponded to the higher iron in the sediment of Hudson Gorge and acid-grid.The heavy metal content of zooplankton, benthos and sediment showed that samples from the acid grid were significantly richer in these elements than the comparable control area samples. However, a broader comparison showed that samples from Hudson Gorge contained the maximum amounts of lead and chromium in benthos as well as the maximum concentrations of all eight metals in the sediment. These data are consistent with the possibility that entrapment in the gorge sediments may be the ultimate fate of the heavy metal enrichment in the New York Bight area and that sources of heavy metals other than acid-iron waste may be substantial.The remaining data reviewed in this study did not demonstrate any adverse in situ effects of acid-iron waste on the distribution of such parameters as dissolved oxygen, chlorophyll α and plant nutrients.Present indications are that the disposal of acid-iron waste in the New York Bight appears to influence standing crops in minor ways considering the magnitude and nature of the waste material involved.

Finite vertical oscillation of fluid parcel in a heterogeneous, incompressible sea water—Part II

The solutions of vertical oscillation of finite amplitude of a fluid parcel in a heterogeneous, incompressible sea water were obtained, solving rigorously the equation of motion, retaining small terms to the third order of the amplitude non-dimensionized by a vertical reference length. The motion is asymmetric with respect to its equilibrium position and the period of motion is longer than that of infinitesimal Vaisala oscillation. When the vertical velocity of the parcel exceeds certain critical value, oscillation of large amplitude sets in near the outskirts of the thermocline, its period being more than twice larger than that of Vaisala oscillation. The apprehension whether this type of the increased vertical motion might be influenced or denied by the horizontal motion in such a case as in internal waves is also discussed. From some observations which will be appeared in Part II, we found oscillations of large amplitude with the period which is in good agreement with the theoretical result.

Finite vertical oscillation of fluid parcel in a heterogeneous, incompressible sea water—Part I

Finite vertical oscillation of fluid parcel in a heterogeneous, incompressible sea water—Part I

クロレラ・エリプソィデアの海水馴化について

Despite success in raising farm animals with chlorella as a basic diet, previous attempts at using this freshwater organism as nutritive source for marine plankton and larvae of shell fish had difficulities in that the chlorella was not always digested well by larval shellfish, and that the propagation in seawater of high salinity (S 34‰) was unfeasibly poor. The present research was designed to explore a possibility of using the chlorella as food for larva of tunas and other fish. The material was prepared by culturing Chlorella ellipsoidea in freshwater which was fed with a diluted liquid fertilizer from time to time. The initial density of the organism in the suspension was 8×106/ml in number of cells. In determining the effect of chlorinity on the propagation the chlorella suspension in experiment A was admixed with seawater (Cl 19‰) at the ratio of 1:1; in experiment B one part of seawater (Cl 19‰) received one half of chlorella suspension twice in two days; in experiment C the culturing water consisting of one chlorella suspension and a quarter of seawater (Cl 19‰) was renewed with a quarter of seawater six times at intervals of two days. While the cultured organism in A and B needed about 40 days to attain a maximum concentration (30×l06/ml), experiment C was effective in producing the concentration of 37×l06/ml in 11 days. Chlorinity at the end of those experiments was respectively 12.50, 16.44, and 21.12‰. During experiment C over a month the average diameter of the cells was reduced from 9.3 to 2.0μ with some of the smallest individuals occurring as early as 10 days after onset of the experiment. In subsequent experiments an increase in the number of cells from the initial level was 15×l06/ml in 15 days for two mean temperatures 16° and 21°C but it was 25×l06/ml in 18 days at 26°C. Among various ratios of inoculation, 1/4, 1/8, 1/16, of chlorella suspension to the culturing seawater, the second one had the best result, increasing the number of cells by 25×l06ml in 20 days. In the presence of a commercial fertilizer, however, the quarter inoculation revealed better effect with an increase of the number of cells being 60×l06/ml in 16 days. On a future occasion detailed accounts of breeding copepods and other zooplankton (50-70μ in diameter) with the chlorella adapted to seawater will be made in connection with its digestibility.

Innervation of the heart of Praunus flexuosus (Mysidacea)

The heart nerves of Praunus flexuosus Leach ( = Macromysis flexuosa White) have been stained with methylene blue applied in various ways. As a rule the animals were injected with a solution prepared immediately before use by mixing 1 part of 0–5 % solution of methylene blue in distilled water or of rongalit white with two parts of sea water. The injection was made into one of the posterior segments of the abdomen with the needle pointing forwards. When three or four animals are treated at the same time, usually in at least one of them the staining reaction takes a satisfactory course and its progress can be observed under the microscope, owing to the transparency of the tissues. In a few minutes after the injection some of the nerves are already visible. Later the coloration becomes more general and more intensive, but soon begins to fade out and can disappear completely.

FACTORS INFLUENCING METAMORPHOSIS OF BUGULA LARVAE

1. In calcium-free van't Hoff's solution and both Na-free and K-free mixtures having the other ions in the same proportion as in sea water at a pH of 7.1-8.0, the larvae of Bugula flabellata behaved exactly like those in sea water containing an excess of MgCl2. Phototropic reactions were lost, ciliated tissue was shed as material migrated basally from the pallial furrow and metamorphosis did not occur.2. In isotonic Mg-free solutions (pH = 8.0) metamorphosis was greatly accelerated, fixation occurring within 30 minutes to 3 hours in the majority of larvae; these organisms developed well-formed zooids in 10 hours. (Normally only about 77% of the larvae metamorphose by 12 hours.)3. Neutral red, methylene blue and, to a lesser extent, eosin accelerated metamorphosis. Neutral red, the most potent of the three, was effective in concentrations of 1:1,000,000 parts of sea water; methylene blue caused acceleration in concentrations of 1:500,000 parts. At a concentration of 1:100,000 parts of neutral red the average duration of the natatory period was about an hour.4. Metamorphosis failed to occur in Ca-free, Na-free and K-free media to which neutral red had been added in proportions of 1:100,000 parts. The same concentration of neutral red in isotonic Mg-free media (pH = 8.0) had a greater accelerating effect than when the dye was added to sea water in the same proportions. A reduction of temperature to 4° C. to 12° C. of sea water containing neutral red in parts of 1:100,000 antagonized the accelerating effects of neutral red. The staining reactions of neutral red and the problems involved in the study of metamorphosis are also discussed.

MINERALS, OLD AND NEW FROM THE SEA*

HAD I been writing a book on the subject I should have first described the crust of the earth, some 20 miles in thickness, and then gone on to point out how, by the processes of destruction and denudation, this is continually being washed first into the rivers and finally into the sea, much of it going into solution. As the poet tells us, “even the weariest river winds somewhere safe to sea”. The quantity of any one constituent of the crust in a thousand parts of sea-water is infinitely small and indeed many are only detectable by the most refined methods of the chemist, but there is so much ocean in the world that in the aggregate it contains many tens of thousands of tons of even the very rarest constituent.

A Critical Examination of the Evidence for Physical and Chemical Influences on Fish Migration

A Critical Examination of the Evidence for Physical and Chemical Influences on Fish Migration