scholarly journals The Examination of Sea Water by an Optical Method

1902 ◽  
Vol 23 ◽  
pp. 35-43
Author(s):  
J. J. Manley
Keyword(s):  
Optical Method ◽  
Royal Society ◽  
Sea Water ◽  
Physical Nature ◽  
Refractive Indices ◽  
Two Samples

In a paper communicated to the Royal Society, Mr E. T. Günther and the author gave an account of the results obtained from the examination of two samples of water taken from Lake Urmi, and amongst other determinations of a chemical and physical nature, were those of the refractive indices, which were performed with the aid of the Royal Society's large quartz prism and spectrometer, the latter reading by means of micrometers to 2″ of arc. On comparing the values obtained for the refractive indices of the two samples of water with those obtained for the relative densities, it was at once apparent that the former differentiated the two samples quite as distinctly as the latter.

Study of optical parameters of two fluorinated isothiocyanato nematic liquid crystals exhibiting high birefringence

2014 ◽  
Vol 22 (1) ◽  
Author(s):  
T. Devi ◽  
B. Choudhury ◽  
A. Bhattacharjee ◽  
R. Dabrowski
Keyword(s):  
Liquid Crystal ◽  
Liquid Crystals ◽  
Laser Beam ◽  
Order Parameter ◽  
Refractive Indices ◽  
Optical Parameters ◽  
Optical Studies ◽  
High Birefringence ◽  
Two Samples ◽  
Direct Extrapolation

AbstractOptical studies have been carried out on two fluorinated isothiocyanato nematic liquid crystal (LC) compounds 4′-butylcyclohexyl-3, 5-difluoro-4-isothiocyanatobiphenyl and 4′-pentylcyclohexyl-3, 5-difluoro-4-isothiocynatobiphenyl. Transition temperatures of the two samples were confirmed using a polarizing microscope. The two LC compounds were found to exhibit fairly high clearing temperatures. Measurements of refractive indices of the two compounds were done by using thin prism method with He-Ne laser beam of wavelength 630 nm. Birefringence of the two LC compounds was calculated from the measured refractive indices. Both the compounds are found to display fairly high values of birefringence. Validation of a modified four-parameter model, based on Vuks equation describing the temperature dependence of refractive indices of the two liquid crystals, is also presented in this paper. The model is validated by fitting the experimentally measured values of refractive indices, birefringence and average refractive indices of the two nematic LCs with the theoretical values. In this paper, the calculation of order parameters of the LCs is presented by using two methods: direct extrapolation method based solely on the birefringence data and by using modified Vuks method based on Haller’s extrapolation. As observed from the obtained results, this procedure of calculating order parameter gives very reasonable results.

On the Cause and Nature of the Chemical Changes occurring in Oceanic Deposits

1897 ◽  
Vol 21 ◽  
pp. 25-34
Author(s):  
W. N. Hartley
Keyword(s):  
Special Reference ◽  
Ammonium Sulphate ◽  
Royal Society ◽  
Sea Water ◽  
Magnesium Carbonate ◽  
Chemical Examination ◽  
Chemical Changes ◽  
Sulphuretted Hydrogen

In Nature of January 24, 1895, appears an abstract of a paper read before the Royal Society of Edinburgh on March 7, 1892, by Dr John Murray and Mr Robert Irvine, and published in the Transactions of the Society, vol. xxxvii. part 2, No. 23, entitled “Chemical Changes between Sea-water and Oceanic Deposits.”This is an account of a chemical examination of the sea-water salts in the water adhering to or retained in mud, with special reference to the formation of the deposit known as “Blue Mud.”Dittmar's analysis of sea-water is quoted and compared with an analysis of mud-water. The chief points of difference between the two is the occurrence in mud-water salts of 0·206 per cent. of ammonium sulphate, 0·729 per cent. of magnesium carbonate, and 0·18 per cent. of manganous carbonate; also that the total salts are low in proportion to the chlorine they contain.The occurrence of ammonium sulphate in this mud, and also of manganous carbonate, are facts of much interest; but there are some equations given to explain the chemical changes which the mud undergoes which are not strictly in accordance with facts. There are three points which I would desire to draw attention to: first, the reduction of the sulphates; second, the oxidation of sulphuretted hydrogen; and third, the formation of manganous carbonate.The equations are written without reference to the part played by water in the chemical changes involved, but it may have been thought that the accuracy sacrificed was compensated by the simpler form of the equations.

XXXIII. Some experiments and researches on the saline contents of sea-water, undertaken with a view to correct and improve its chemical analysis

1822 ◽  
Vol 112 ◽  
pp. 448-456 ◽  
Keyword(s):  
Chemical Analysis ◽  
Royal Society ◽  
Sea Water ◽  
Sufficient Accuracy ◽  
Sea Salt ◽  
The Earth

In a paper on the temperature and saltness of various seas, which the Royal Society did me the honour to publish in their Transactions for the year 1819, I threw out a conjecture, that the sea might contain minute quantities of every substance in nature, which is soluble in water. For the ocean having communication with every part of the earth through the rivers, all of which ultimately pour their waters into it; and soluble substances, even such as are theoretically incom­patible with each other, being almost in every instance capable of co-existing in solution, provided the quantities be very minute, I could see no reason why the ocean should not be a general receptacle of all bodies which can be held in solution. And although it will appear from the following account, that I have been unsuccessful in some of my attempts to prove the truth of this conjecture, it may fairly be ascribed either to a want of sufficient accuracy in our present methods of chemical analysis, or of the requisite degree of skill in the operator. Some time after the communication to which I have just referred, an extraordinary statement was pointed out to me, upon the authority of Rouelle, a French chemist of the last century, from which it appeared that mercury was contained in sea salt: and I saw soon after in the ‘ Annales du Musée ,' Vol. VII. a paper by the celebrated chemist Proust, who, in a great measure, confirmed that statement, by announcing that he had found traces of mercury in all the specimens of marine acid which he had examined.

scholarly journals VIII. An account of Mr. Applebyʼs process to make sea-water fresh; with some expe­riments therewith; communicated to the Royal Society, by W. Watson, F. R. S

1753 ◽  
Vol 48 ◽  
pp. 69-71 ◽  
Keyword(s):  
Royal Society ◽  
Sea Water

The making sea-water fresh has been frequently attempted, and several accounts thereof, from time to time, been communicated to the Royal Society.

scholarly journals The relation of thallium to the alkali metals: a study of thallium-zinc sulphate and selenate

1910 ◽  
Vol 83 (561) ◽  
pp. 211-226 ◽  
Keyword(s):  
Royal Society ◽  
Alkali Metals ◽  
Zinc Sulphate ◽  
Refractive Indices ◽  
Optical Investigation ◽  
Principal Angles ◽  
Double Salts ◽  
Magnesium Salts ◽  
Optical Examination

In a communication made to the Royal Society in May, 1907, the results of the study of the normal sulphate and selenate of thallium were presented, and certain interesting conclusions concerning the position of the thallium salts in the rhombic series R 2 S Se O 4 discussed. It became particularly important that a similar study should be made of the monoclinic double salts of the series R 2 M ( S Se O 4 ) 2 .6H 2 O containing thallium as the R-metal, not only for the sake of confirming or otherwise the conclusions arrived at from the study of the simple salts, but also because it is desirable that the investigation of the monoclinic series of double salts should be completed as far as possible by the inclusion of the thallium salts of the series. For this reason, a begining has been made with the two salts containing zine as the M-metal, preliminary attempts at preparing a number of thallium salts of the series having shown that while all these salts, in general, were very difficult to prepare in good and transparent crystals of thallium-zinc sulphate were least difficult to obtain. The greatest difficulty of all is to procure them free from opacity, and while eventually excellent crystals of thallium-zinc sulphate were obtained of adequate transparency to permit of a complete optical investigation, thallium-zinc selenate has invariably proved white and opaque, and resisted all efforts at optical examination. Both salts, however, have been thoroughly investigated goniometrically, and thallium-zinc sulphate not only optically but also as regards its volume. The magnesium salts, which it was hoped to have included in this memoir, results at all comparable with the author's previous work. The crystals of the sulphate and selenate of thallium and zinc were both measured by Werther as regards a few of the principal angles, and later the crystals of the double sulphate were measured by Des Cloizeaux, who also examined some of the optical characters of the salt. The density of this salt and also its refractive indices were subsequently determined by Perrot.

On the refractive indices and densities of normal and semi-normal aqueous solutions of hydrogen chloride and the chlorides of the alkalis

1899 ◽  
Vol 64 (402-411) ◽  
pp. 308-318 ◽  
Keyword(s):  
Aqueous Solutions ◽  
Hydrogen Chloride ◽  
Royal Society ◽  
Chemical Society ◽  
Inorganic Salts ◽  
Refractive Indices ◽  
Uniform Temperature ◽  
Different Temperatures

A very large number of observations have been made of the refractive indices and densities of aqueous solutions of inorganic salts and acids: in England, more especially, by Dr. J. H. Gladstone, who in a paper in the ‘Philosophical Transactions’ for 1870, gave the values he had obtained for the refractive indices and densities of some 160 salts and acids; and in a series of papers published subsequently in the 'Journal of the Chemical Society,’ has given the results of further observations. Most, however, of these determinations have been made with solutions of different strengths, and at different temperatures, and, therefore, I venture to bring before the Royal Society an account of some observations I have made of the refractive indices and densities of normal and semi-normal aqueous solutions of hydrogen chloride, and the chlorides of the alkalis at a uniform temperature of 18°.

scholarly journals The refractive indices of water and of sea-water

1906 ◽  
Vol 78 (525) ◽  
pp. 406-409 ◽  
Keyword(s):  
Sea Water ◽  
Focal Length ◽  
New Method ◽  
Refractive Indices ◽  
Critical Part

1. Method of Observation .—Measurements of the refractive indices of water have been made by Fraunhofer, Gladstone, Van der Willigen, Dufet, Pulfrich, and many others. Those now offered were made by the new method previously described. 2. Instruments .—In addition to the instrument used for measuring the refractive indices of fluorite quartz and calcite, a larger goniometer has been employed, especially for determining the temperature-refraction coefficients and for the critical part of the work generally. This instrument has quartz objectives of 3 inches diameter and 27·5 inches focal length, and quartz-calcite objectives of 2·375 inches diameter and the same focal length, and it has a divided circle of 18 inches diameter. There are two micrometers with reading microscopes, one on each side of the circle. These micrometers are similar to that of the smaller goniometer before described, and readings were taken in the same way. The hollow prism (by Hilger) used to contain the water has a clear aperture 1·675 inches by 2·375 inches, and is entirely of quartz. It can be used on either instrument (see Appendix).

scholarly journals XIII. An examination of Sea-water frozen and melted again, to try what quantity of salt is contained in such ice, made in Hudson's Streights by Capt. Christopher Middleton, F. R. S. at the request of C. Mortimer, R. S. Secr

1740 ◽  
Vol 41 (452) ◽  
pp. 806-807
Keyword(s):  
Mediterranean Sea ◽  
Royal Society ◽  
Sea Water ◽  
Made In

Dr. Hales , in his learned Paper lately read at the Royal Society, wherein he proposes a Method of rendering Sea-water fresh, and wholsome to drink, mentions a Diversity of Saltness of the Water at the Nore in the Mouth of the Thames , and the Water taken up in the Mediterranean Sea , this containing 1/27 of Salt, the former 1/29.

The Physical Nature of the Lipid Globules in the Living Neurones of Helix aspersa as indicated by Measurements of Refractive Index

1957 ◽  
Vol s3-98 (43) ◽  
pp. 341-348
Author(s):  
K.F. A. ROSS ◽  
J.T. Y. CHOU
Keyword(s):  
Refractive Index ◽  
Physical Nature ◽  
Helix Aspersa ◽  
Refractive Indices ◽  
Refractive Index Measurement ◽  
Cytoplasmic Inclusions ◽  
Additional Information ◽  
Physico Chemical ◽  
Index Measurement ◽  
Made In

The lipid globules in the neurones of Helix aspersa have been found by Chou in 1957 to be of three distinct kinds that differ from each other in chemical composition. In the present investigation, the refractive indices of these three kinds of globule were measured by the technique for measuring the refractive indices of cytoplasmic inclusions in living cells developed by Ross in 1954, which is here described in detail. It was found that the refractive indices of the globules containing mixed lipids and proteins and those that probably contained triglycerides alone, all had relatively high efractive indices of about 1.47-1.50. These values are comparable with the known refractive indices of many pure lipids. The refractive indices of the globules containing phospholipid were much lower, being about 1.41-1.42, which is lower than that of any pure lipid. This indicates that these globules probably also contain appreciable amounts of water associated with the phospholipid molecules, as was suggested by Schmidt in 1939. The results also show that refractive index measurement made in conjunction with histochemical investigations may, in some cases, provide useful additional information about the physico-chemical nature of cell constituents.

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