On the specific gravity and temperatures of sea-waters, in different parts of the ocean, and in particular seas; with some account of their saline contents

1833 ◽  
Vol 2 ◽  
pp. 111-112
Keyword(s):  
Specific Gravity ◽  
Southern Ocean ◽  
Southern Hemisphere ◽  
Sea Water ◽  
Distilled Water ◽  
Total Separation ◽  
Different Depths ◽  
The Mean ◽  
The Difference ◽  
Different Parts

After some preliminary remarks upon the labours of others in this department of inquiry, Dr. Marcet proceeds to the immediate objects of his own investigation, which were to ascertain the specific gravity of many specimens of sea-water from different parts, and afterwards to examine their saline contents. The results relating to the first of these objects are prefaced by an account of the mode of taking the specific gravities, and of the instrument by which the water was raised, and of which two plates are annexed. The author then proceeds to the inferences deducible from his experiments, which, for the sake of conciseness, are given in the form of tables; whence it appears that the ocean in the Southern hemisphere is rather more salt than in the Northern, in the proportion of 1029.19 to 1027.57. The mean specific gravity of specimens from various parts of the equator, is 1027.77, and therefore a little exceeds that prevalent in the Northern hemisphere, while it is decidedly less than that of the Southern Ocean. There is no material difference between different east and west longitudes at the equator, nor in the same hemisphere. In general, the salt seems most abundant in the deepest water, and in that furthest from land; the vicinity of ice also diminishes the saltness: if therefore this quality should increase in approaching the pole, it may be considered as militating against the probability of the ocean being extensively frozen in those regions. In general, small inland seas, communicating with the ocean, are less salt than the ocean itself. The waters of the Mediterranean, however, are more saline, and in attempting to account for this circumstance, the author’s attention is directed to the relative densities of water from different depths of the ocean; and though in some cases it appeared lightest at the surface, such a result was generally referable to the vicinity of thawing ice, for, in ordinary circumstances, the density at great depths in no instance exceeded the mean density of the waters of the ocean. In regard, however, to different seas or arms of the ocean, the case is often different, in consequence of local circumstances. At the entrance of the Dardanelles, for instance, the difference between the upper and lower strata is as 1020 to 1028. Dr. Marcet next details some researches upon the congelation of sea-water which takes place at 28°, and when slowly effected, is always attended by the total separation of the salt, which forms a strong brine that is washed away by the neighbouring water. The different specimens of water obtained from the ice in the late Northern Expedition, varied very little in specific gravity; the water was sweet, and in many instances its specific gravity did not exceed that of distilled water.

scholarly journals Analysis and Development of Seawater Density Measurement Algorithms Using Arduino Uno and YL-69 Sensor

2020 ◽  
Vol 4 (5) ◽  
pp. 951-956
Author(s):  
Miftahul Walid ◽  
Hozairi ◽  
Madukil Makruf
Keyword(s):  
Sea Water ◽  
Density Measurement ◽  
Absolute Error ◽  
Error Level ◽  
Value Range ◽  
Density Values ◽  
The Mean ◽  
Arduino Uno ◽  
The Difference ◽  
Predicted Values

In this research, an analysis was carried out to develop a measuring instrument for seawater density in salt production using a microcontroller (Arduino Uno) and YL-69 sensor, this sensor was commonly used to measure soil moisture. The experimental method was used in this research to produce initial data in the form of resistance and seawater density values, then calculations are carried out using statistical methods to find equations and produce a constant variable that connects the resistance and seawater density values. The equation was used to compile the algorithm into Arduino Uno. As for the results of this research,  From six experiments conducted, two experiments produced the same sea water density value between the actual and the predicted, namely the 2nd and 5th experiments, while for other experiments there was a difference between the actual and predicted values, however, it was not too significant, the difference occurs between the value range 0 ~ 1, to determine the level of error, use the Mean Square Error (MSE) with an error level of = 0.5 and Mean Absolute Error (MAE) with an error level of = 0.6. The contribution of this research is an algorithm that can predict the density value (baume) based on the resistance value obtained from the YL 69 sensor.

scholarly journals IV. On the composition of sea-water in the different parts of the ocean

1865 ◽  
Vol 155 ◽  
pp. 203-262 ◽  
Keyword(s):  
Sea Water ◽  
Metamorphic Rocks ◽  
Chemical Examination ◽  
Different Depths ◽  
The Mediterranean ◽  
Short Time ◽  
Different Parts

In the year 1843 a friend of mine, Mr. Ennis of Falmouth, sent me some bottles of seawater from the Mediterranean, which I subjected to a chemical examination, a work which induced me to collect what other chemists had determined about the constitution of the water of the great Ocean. This labour convinced me that our knowledge of, the composition of sea-water was very deficient, and that we knew very little about the differences in composition which occur in different parts of the sea. I entered into this labour more as a geologist than as a chemist, wishing, principally to find facts which could serve as a basis for the explanation of those effects, that have taken place at the formation of those voluminous beds which once were deposited at the bottom of the ocean. I thought that it was absolutely necessary to know with precision the composition of the water of the present ocean, in order to form an opinion about the action of that ocean from which the mountain limestone, the oolite and the chalk with its flint have been deposited, in the same way as it has been of the most material influence upon science to know the chemical actions of the present volcanos, in order to determine the causes which have acted in forming the older plutonic and many of the metamorphic rocks. Thus I determined to undertake a series of investigations upon the composition of the water of the ocean, and of its large inlets and bays, and ever since that time I have assiduously collected and analyzed water from the different parts of the sea. It is evident that it was impossible to collect this material in a short time, and without the assistance of many friends of science, and I most gratefully acknowledge how much I am indebted to many distinguished officers of the Danish and British Navy, as well as to many private men, who were all willing to undertake the trouble carefully to collect samples of sea-water from different parts of the ocean, both from the surface and from different depths. I shall afterwards, when giving the particular analyses, find an opportunity to mention the name of each of those to whom I am indebted for my material.

scholarly journals An intercomparison of subtropical cut-off lows in the Southern Hemisphere using recent reanalyses: ERA-Interim, NCEP-CFRS, MERRA-2, JRA-55, and JRA-25

2019 ◽  
Vol 54 (1-2) ◽  
pp. 777-792 ◽  
Author(s):  
Henri Rossi Pinheiro ◽  
Kevin Ivan Hodges ◽  
Manoel Alonso Gan
Keyword(s):  
Southern Hemisphere ◽  
Separation Distance ◽  
Data System ◽  
Track Density ◽  
Reanalysis Product ◽  
Spatial Differences ◽  
The Mean ◽  
The Difference

AbstractFour recent reanalysis products ERA-Interim, NCEP-CFSR, MERRA-2 and JRA-55 are evaluated and compared to an older reanalysis JRA-25, to quantify their confidence in representing Cut-off lows (COLs) in the Southern Hemisphere. The climatology of COLs based on the minima of 300-hPa vorticity ($$\xi_{300}$$ξ300) and 300-hPa geopotential ($$Z_{300}$$Z300) provides different perspectives of COLs and contributes to the understanding of the discrepancies observed in the literature regarding their numbers and seasonality. The COLs compare better among the newest reanalyses than compared to the older reanalysis JRA-25. The difference in number between the latest reanalyses are generally small for both $$\xi_{300}$$ξ300 and, with more COLs identified in $$\xi_{300}$$ξ300 than in $$Z_{300}$$Z300 for all reanalyses. The spatial differences observed between the newest reanalyses are mainly due to differences in the track lengths, which is larger in ERA-Interim and JRA-55 than in NCEP-CFSR and MERRA-2, resulting in disparities in the track density. This is likely due to the difference in the assimilation data system used in each reanalysis product. The largest differences in intensities occur in the $$\xi_{300}$$ξ300, because this field is very sensitive to the reanalysis resolution. The mean separation distance of the COLs that match between the latest reanalyses are generally small, while the older JRA-25 has a broader distribution and larger number of matches with relatively large distances, indicating larger uncertainties in location of COLs. The results show significant improvements for the most recent reanalyses compared to the older JRA-25 reanalysis, indicating a progress in representing the COL properties.

Osmoregulation in Ligia Oceanica and Idotea Granulosa

1963 ◽  
Vol 40 (2) ◽  
pp. 381-392
Author(s):  
MARY E. TODD
Keyword(s):  
Blood Concentration ◽  
Sea Water ◽  
Freezing Point ◽  
Freezing Point Depression ◽  
External Concentration ◽  
Osmotic Concentration ◽  
Test Range ◽  
The Mean ◽  
The Difference ◽  
Idotea Granulosa

1. The osmoregulatory response of Ligia oceanica and Idotea granulosa to the range of the experimental variables was similar. They were both hyperosmotic relative to the medium and the difference between internal and external concentration increased as the salinity of the medium decreased. 2. In 100% sea water the osmotic concentration of the blood of Ligia oceanica was markedly above that of the medium, whereas in Idotea granulosa the blood was only marginally hyperosmotic. 3. In Ligia oceanica the blood concentration changed little in 100 and 75% sea water, but dropped significantly between 75 and 50% sea water, whereas blood concentration in Idotea granulosa dropped significantly throughout the test range of salinities. 4. The more efficient osmoregulation of Ligia oceanica in 25% sea water is reflected in the mean freezing-point depression of the blood, Δi = 1.65, compared with Δi = 0.90 in Idotea granulosa. 5. In both species the osmotic concentration of the blood was influenced by season, by temperature and by a temperature-salinity interaction. 6. Neither size nor sex of the animal influenced osmotic concentration of the blood.

XII. On the specific gravity, and temperature of sea waters, in different parts of the ocean, and in particular seas; with some account of their saline contents

1819 ◽  
Vol 109 ◽  
pp. 161-208 ◽  
Keyword(s):  
Chemical Analysis ◽  
Sea Water ◽  
Dead Sea ◽  
The Arctic ◽  
Natural Consequence ◽  
Chemical Examination ◽  
Arctic Regions ◽  
Different Depths ◽  
The Subject ◽  
Different Parts

While analyzing the waters of the Dead Sea and the River Jordan, about twelve years ago, and conversing on the peculiarities of these waters with a late valuable and lamented Member of this Society, Mr. Tennant, it occurred to us that a chemical examination of different seas, in a variety of latitudes and at different depths, might be interesting; and that, however unlikley to be productive of any striking discovery, such an inquiry, conducted with due care and attention, might afford curious results, and throw some light on this obscure subject. We accordingly began to collect specimens of sea water from various parts of the globe, and it was agreed that I should aided by Mr. Tennant's occasional advice, submit them to chemical analysis. In the course of a few years I became possessed, through the kindness of several friends, of a great variety of specimens of sea water; and I was preparing to examine them, when a most deplorable accident deprived science of the sagacious philosopher from whose friendship and enlightened assistance I had anticipated so much advantage. Procrastination and delay were the natural consequence of this misfortune; and I should probably have entirely lost sight of the subject, had not my intention been again directed to it by the late expeditions to the Arctic regions, and the great zeal and kindness of some of the officers engaged in them, in procuring for me specimens of sea water, collected in different latitudes, and under peculiar circumstances, so as to add greatly to the value of those which I previously possessed.

On the specific gravity of mercury

1867 ◽  
Vol 15 ◽  
pp. 10-11
Keyword(s):  
Specific Gravity ◽  
Sulphuric Acid ◽  
Distilled Water ◽  
The Mean

Some time since, in connexion with a research on the fusing-point of mercury, several observations were made at Kew of the specific gravity of this fluid. A specific-gravity bottle was used for this purpose and it was washed, in the first place with sulphuric acid, secondly with distilled water, and thirdly with alcohol; when this was done it was found to contain mercury without any air-specks or any diminution of that metallic lustre which pure mercury exhibits when in contact with a vessel of clean glass. Three different specimens of pure mercury were used and were separately weighed in the specific-gravity bottle at 62° Fahr. The following results were obtained:- Mercury from the cistern of the old Kew Weighted in air. grs. standard barometer, filling the bottle, V 13591·36 weighed at 62° F. ............ ... . . . . . . . Mercury from the cistern of the new Kew 1 , standard barometer weighed at 62° F. 13591·66 Mercury used in experiments with airthermometer weighed at 62° F . . .... 13591·96 the mean of these will be 13591·66 grs.

scholarly journals Asymmetry between galaxies with different spin patterns: A comparison between COSMOS, SDSS, and Pan-STARRS

2020 ◽  
Vol 29 (1) ◽  
pp. 15-27 ◽  
Author(s):  
Lior Shamir
Keyword(s):  
Spiral Galaxy ◽  
Spiral Galaxies ◽  
Automatic Process ◽  
Human Intervention ◽  
Rotation Direction ◽  
The Earth ◽  
Fully Automatic ◽  
The Mean ◽  
The Difference ◽  
Different Parts

AbstractPrevious observations of a large number of galaxies show differences between the photometry of spiral galaxies with clockwise spin patterns and spiral galaxies with counterclockwise spin patterns. In this study the mean magnitude of a large number of clockwise galaxies is compared to the mean magnitude of a large number of counterclockwise galaxies. The observed difference between clockwise and counterclockwise spiral galaxies imaged by the space-based COSMOS survey is compared to the differences between clockwise and counterclockwise galaxies imaged by the Earth-based SDSS and Pan-STARRS around the same field. The annotation of clockwise and counterclockwise galaxies is a fully automatic process that does not involve human intervention, and in all experiments both clockwise and counterclockwise galaxies are separated from the same fields. The comparison shows that the same asymmetry was identified by all three telescopes, providing strong evidence that the rotation direction of a spiral galaxy is linked to its luminosity as measured from Earth. Analysis of the luminosity difference using a large number of galaxies from different parts of the sky shows that the difference between clockwise and counterclockwise galaxies changes with the direction of observation, and oriented around an axis.

The influence of dead spaces and the designs of injectors on the amount of drug dose in intra-vitreal injection

2020 ◽  
pp. 112067212097782
Author(s):  
Erol Havuz ◽  
Seda Güdül Havuz ◽  
Onur Gokmen
Keyword(s):  
Drug Dose ◽  
Distilled Water ◽  
Becton Dickinson ◽  
Maximum Increase ◽  
Percent Error ◽  
Before And After ◽  
Drug Doses ◽  
The Mean ◽  
The Dead ◽  
The Difference

Aim: To evaluate the dead spaces resulting from different designs of the insulin injectors used for intravitreal injections and the amounts of drug doses. Methods: In the study, five different brands of sterile insulin injectors of 1 mL were used for the test. The weight of the injectors was determined before and after filling the injectors with 0.05 and 0.1 mL distilled water. The weight of the injectors was measured with and without the needle after the water within the injectors had been taken out and weight differences were measured. The difference between the intended amount of fluid to be thrown out and the weight of the fluid remaining in the injector was calculated as percent error. Results: After throwing out 0.05 mL distilled water from the injector, weights of the Beybi®, Traf®, Becton Dickinson®, Ayset®, and Setojet® brands of injectors with 30 G needle were detected to increase the mean 0.0220 ± 0.006 g, 0.0208 ± 0.008 g, 0.0355 ± 0.016 g, 0.0219 ± 0.017 g, and 0.0150 ± 0.007 g, respectively compared to the weights of the dry injectors. The 0.1 mL injector group was found to be mean 0.0350 ± 0.014 g, 0.0264 ± 0.008 g, 0.0405 ± 0.015 g, 0.0272 ± 0.013 g, and 0.0245 ± 0.014 g, respectively. The maximum increase due to the dead spaces in the injectors was found in the Becton Dickinson® injector, both in the 0.05 mL and the 0.1 mL groups ( p < 0.000). Conclusion: The injector designs may affect the dose of IVI required to be given. More correct amounts of drugs may be administered via the intra-vitreal route through designs that reduce the dead spaces at the end part of the injector and between the inner wall and the plunger.

scholarly journals The buoyancy of plankton diatoms: a problem of cell physiology

1948 ◽  
Vol 135 (880) ◽  
pp. 382-389 ◽  
Keyword(s):  
Specific Gravity ◽  
Vegetative Cell ◽  
Sea Water ◽  
Mean Value ◽  
Cell Physiology ◽  
Resting Spore ◽  
Resting Spores ◽  
Pure Cultures ◽  
The Mean ◽  
Volume Difference

Observations on pure cultures of diatoms and the results of centrifuge experiments showed that under optimal conditions the vegetative cells have the same specific gravity as sea water. The specific gravity of resting spores is significantly higher than that of sea water. Hence the specific gravity of the cell sap which fills the bulk of the vegetative cell and is expelled during formation of the resting spore is lower than that of sea water. The reduced weight (i. e. weight underwater) of resting spores of Ditylum was measured by means of the Cartesian diver balance. The mean value obtained was 0·00312 γ per spore. From calculations of the volume difference between the vegetative cell and the resting spore the specific gravity of the cell sap was estimated at 1·0202, i. e. 0·0025 less than that of the sea water used. It is suggested that the mechanism underlying buoyancy in plankton diatoms is similar to that involved in the flotation of Halicystis and consists in the maintenance of very low con­centrations of divalent ions in the cell sap, the result of a steady expenditure of energy.

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