scholarly journals XIII. On the velocities of the ions

1895 ◽  
Vol 186 ◽  
pp. 507-522 ◽  
Keyword(s):  
Royal Society ◽  
Cobalt Nitrate ◽  
The Other ◽  
Salt Solutions ◽  
Previous Communication ◽  
A Current

In a previous communication to the Royal Society (‘Phil. Trans.,’ 184 (1893), A, p. 337), I have described a method of experimentally determining the velocities of the ions during electrolysis, by observations on the phenomena at the junction of two salt solutions, one at least of which is coloured, when a current of electricity is passed from one to the other. For the success of the method it is necessary to choose two solutions which (1) are different in density, (2) different in colour, and (3) have nearly equal conductivities at equivalent concentrations, i. e , when the number of gram-molecules dissolved in 1 litre of solution is the same for both. These conditions seriously restrict the number of cases to which the method is applicable, but the results obtained for copper and for the bichromate group (Cr 2 O 7 ) agree well with the values theoretically deduced by Kohlrattsch from measurements of the conductivity. Alcoholic solutions of cobalt nitrate and chloride were also used, and the sum of the velocities of the opposite ions, in each case, observed in my experiments, was as nearly as could be expected, the same as their sum calculated from the conductivities by Kohlrausch’s method.

scholarly journals V. On the velocities of the ions

1895 ◽  
Vol 58 (347-352) ◽  
pp. 182-187 ◽  
Keyword(s):  
Royal Society ◽  
Experimental Error ◽  
Salt Solutions ◽  
Previous Communication ◽  
A Current

In a previous communication to the Royal Society (‘Phil. Trans.,’ 184, (1893), A. p. 337), I have described a method of experimentally determining the velocities of the ions during electrolysis, by observations on the phenomena which occur when a current of electricity is passed across the junction of two salt solutions, one at least of which is coloured. The results obtained agreed, within the limits of experimental error, with the numbers deduced by Professor F. Kohlrausch from measurements of the conductivities. The method is, however, seriously restricted by the conditions necessary for its success. The two solutions must be of different densities, of different colours, and of nearly equal conductivities at equivalent concentrations.

XXVIII. On the nature of the forces concerned in producing the greater magnetic disturbances

1862 ◽  
Vol 152 ◽  
pp. 621-638 ◽  
Keyword(s):  
Royal Society ◽  
The Other ◽  
Iron Core ◽  
Secondary Currents ◽  
The Earth ◽  
Other Hand ◽  
Previous Communication ◽  
Abrupt Changes ◽  
Magnetic Disturbances

1. In a previous communication submitted to the Royal Society on June 28th, 1861, and since published in their Transactions, I ventured to make a suggestion regarding the nature of that connexion which subsists between magnetic disturbances, earth-currents, and auroras. In this hypothesis the earth was viewed as similar to the soft iron core of a Ruhmkorff’s machine, in which a primary disturbing current was supposed to induce mag­netism. Earth-currents and auroras, on the other hand, were viewed as induced or secondary currents, caused by the small but abrupt changes which are constantly taking place in the strength of the primary disturbing current, these changes being very much heightened in effect by the action of the iron core, that is to say, of the earth.

II. On Appold’s apparatus for regulating temperature and keeping the air in a building at any desired degree of moisture

1867 ◽  
Vol 15 ◽  
pp. 144-146
Keyword(s):  
Royal Society ◽  
The Other ◽  
Temperature Regulator ◽  
Steam Power ◽  
Automatic Temperature ◽  
Dwelling House ◽  
At Command ◽  
The Many ◽  
A Current

Those Fellows of the Royal Society who were acquainted with the late Mr. John George Appold, have often expressed their admiration at the various scientific arrangements which he from time to time adapted to his dwelling, house in Wilson Street, Finsbury Square. However intense might be the frost of winter or the heat of summer, or the brilliancy of the gas with which his rooms were lighted, when once under his hospitable roof you enjoyed a pure and refreshing atmosphere. Much of this was undoubtedly due to the steam-power he always had at command connected with his business premises immediately adjacent to his dwelling-house, by which he could at any time force a current of fresh air at a given temperature into any of his rooms; indeed Mr. Appold always contended that houses could not be made thoroughly comfortable as habitations without the aid of steam-power. But among the many of his arrangements to obtain equable temperature in rooms, there were also those that do not require the aid of steam-power, so seldom applicable in private dwellings, and which, being easy of adaptation, might be used in private houses with much advantage as regards the health and comfort of the inmates. I allude to his Automatic Temperature regulator, and to his Automatic Hygrometer; and these instruments, as originally constructed by her late husband, and used for many years in their house, but now repaired and placed in perfect working order by Mr. Browning, Mrs. Appold has requested me to offer in her name to the President and Council of the Royal Society. She desires me to express a hope that they will oblige her by retaining them among the other scientific apparatus belonging to the Royal Society, as a mark of respect to the memory of one who always highly esteemed the honour he received when he was elected into that body in June 1853.

Rem Study of Current Effect on the Structure of Clean Si(111) Surface

1990 ◽  
Vol 48 (1) ◽  
pp. 306-307
Author(s):  
A. Yamanaka ◽  
H. Ohse ◽  
K. Yagi
Keyword(s):  
The Other ◽  
Current Direction ◽  
Clean Surface ◽  
Current Effect ◽  
Atomic Steps ◽  
Step Bunching ◽  
Terrace Width ◽  
Step Down ◽  
A Current

Recently current effects on clean and metal adsorbate surfaces have attracted much attention not only because of interesting phenomena but also because of practically importance in treatingclean and metal adsorbate surfaces [1-6]. In the former case, metals deposited migrate on the deposit depending on the current direction and a patch of the deposit expands on the clean surface [1]. The migration is closely related to the adsorbate structures and substrate structures including their anisotropy [2,7]. In the latter case, configurations of surface atomic steps depends on the current direction. In the case of Si(001) surface equally spaced array of monatom high steps along the [110] direction produces the 2x1 and 1x2 terraces. However, a relative terrace width of the two domain depends on the current direction; a step-up current widen terraces on which dimers are parallel to the current, while a step-down current widen the other terraces [3]. On (111) surface, a step-down current produces step bunching at temperatures between 1250-1350°C, while a step-up current produces step bunching at temperatures between 1050-1250°C [5].In the present paper, our REM observations on a current induced step bunching, started independently, are described.Our results are summarized as follows.(1) Above around 1000°C a step-up current induces step bunching. The phenomenon reverses around 1200 C; a step-down current induces step bunching. The observations agree with the previous reports [5].

Endo-D-galacturonanase immobilized by adsorption on porous polyethyleneterephthalate

1982 ◽  
Vol 47 (10) ◽  
pp. 2716-2723 ◽  
Author(s):  
Lubomíra Rexová-Benková ◽  
Jiřina Omelková ◽  
Vladimír Kubánek
Keyword(s):  
Ionic Strength ◽  
High Stability ◽  
Relative Activity ◽  
Operational Stability ◽  
The Other ◽  
Fixation Strength ◽  
Action Pattern ◽  
Salt Solutions ◽  
Buffer Solution ◽  
Degradation Degree

Endo-D-galacturonanase of Aspergillus sp. was irreversibly adsorbed on polyethyleneterephthalate in an acetate 0.1 mol l-1 buffer solution of pH 4.2. Immobilization of the enzyme resulted in lowering of its activity, the measure of which depended on the amount of the enzyme fixed on the carrier. The highest relative activity (42.4%) had the preparation containing 5.25 mg of the enzyme per 1 g of the carrier. The velocity and intensity of the sorption of the enzyme depended on the ionic strength of the medium, whilst pH, on the other hand, was of no influence. Endo-D-galacturonanase immobilized in a 0.1 mol l-1 buffer was characteristic a) of its fixation strength in salt solutions of various ionic strength and pH, in a 3 mol l-1 guanidine solution, and also in sodium pectate and pectin solutions, b) of its high stability during a long-lasting storage at 4 °C, c) of its operational stability. The immobilization led to a partial change of the action pattern onto the high-molecular substrate, manifested in lowering the decrease of viscosity to degradation degree ratio.

scholarly journals Description of a new barometer, recently fixed up in the apart­ments of the Royal Society; with remarks on the mode hitherto pursued at various periods, and an account of that which is now adopted, for correcting the observed height of the mercury in the society’s barometer

1843 ◽  
Vol 4 ◽  
pp. 1-3
Keyword(s):  
Royal Society ◽  
The Other ◽  
Chemical Effect ◽  
The Absolute ◽  
The One ◽  
And Control ◽  
Usual Scale

The barometer, here alluded to, may in some measure be consi­dered as two separate and independent barometers, inasmuch as it is formed of two distinct tubes dipping into one and the same cistern of mercury. One of these tubes is made of flint glass, and the other of crown glass, with a view to ascertain whether, at the end of any given period, the one may have had any greater chemical effect on the mercury than the other, and thus affected the results. A brass rod, to which the scale is attached, passes through the framework, between the two tubes, and is thus common to both : one end of which is furnished with a fine agate point, which, by means of a rack and pinion moving the whole rod, may be brought just to touch the surface of the mercury in the cistern, the slightest contact with which is immediately discernible; and the other end of which bears the usual scale of inches, tenths, &c.; and there is a separate vernier for each tube. A small thermometer, the bulb of which dips into the mercury in the cistern, is inserted at the bottom : and an eye­piece is also there fixed, so that the agate point can be viewed with more distinctness and accuracy. The whole instrument is made to turn round in azimuth, in order to verify the perpendicularity of the tubes and the scale. It is evident that there are many advantages attending this mode of construction, which are not to be found in the barometers as usu­ally formed for general use in this country. The absolute heights are more correctly and more satisfactorily determined ; and the per­manency of true action is more effectually noticed and secured. For, every part is under the inspection and control of the observer; and any derangement or imperfection in either of the tubes is imme­diately detected on comparison with the other. And, considering the care that has been taken in filling the tubes, and setting off the scale, it may justly be considered as a standard barometer . The pre­sent volume of the Philosophical Transactions will contain the first register of the observations that have been made with this instru­ment.

Robert Hooke: A fractographic study of Kettering–stone

1997 ◽  
Vol 51 (1) ◽  
pp. 45-55 ◽  
Author(s):  
Derek Hull
Keyword(s):  
Royal Society ◽  
The Other ◽  
Microscopical Observation ◽  
Robert Hooke ◽  
Fractographic Study

Observ. XV. illustrated by Schem. IX. Figur:1 (figure 1 of this paper) in Robert Hooke's Micrographia (1665)1 is a description of Kettering–stone ‘which is brought from Kettering in Northampton–shire, and digg’d out of a Quarry, as I am inform'd’. As Curator of Experiments for the Royal Society from 1662, Hooke was charged by the Society to bring in at every meeting one microscopical observation at least. The minutes of the Society2 record that on 15 April 1663 ‘Mr Hooke showed the Company two Microscopicall Schemas; one representing the Pores of Cork … the other a Kettering Stone, appearing to be composed of Globules; and those hollow ones, each having 3 Coatings, sticking to one another, and so making up one entire firm stone’.

scholarly journals V. A letter on a canal in the medulla spinalis of some quadrupeds

1809 ◽  
Vol 99 ◽  
pp. 146-147
Keyword(s):  
Royal Society ◽  
Human Subject ◽  
Cauda Equina ◽  
The Other ◽  
Small Stream ◽  
Spinal Marrow ◽  
The Brain ◽  
Contrary Direction

Sir, According to your request, I send you an account of the facts I have ascertained, respecting a canal I discovered in the year 1803, in the medulla spinalis of the horse, bullock, sheep, hog, and dog; and should it appear to you deserving of being laid before the Royal Society, I shall feel myself particularly obliged, by having so great an honour conferred upon me. Upon tracing the sixth ventricle of the brain, which corresponds to the fourth in the human subject, to its apparent termination, the calamus scriptorius, I perceived the appearance of a canal, continuing by a direct course into the centre of the spinal marrow. To ascertain with accuracy whether such structure existed throughout its whole length, I made sections of the spinal marrow at different distances from the brain, and found that each divided portion exhibited an orifice with a diameter sufficient to admit a large sized pin; from which a small quantity of transparent colourless fluid issued, like that contained in the ventricles of the brain. The canal is lined by a membrane resembling the tunica arachnoidea, and is situated above the fissure of the medulla, being separated by a medullary layer: it is most easily distinguished where the large nerves are given off in the bend of the neck and sacrum, imperceptibly terminating in the cauda equina. Having satisfactorily ascertained its existence through the whole length of the spinal marrow, my next object was to discover whether it was a continued tube from one extremity to the other: this was most decidedly proved, by dividing the spinal marrow through the middle, and pouring mercury into the orifice where the canal was cut across, it passed in a small stream, with equal facility towards the brain (into which it entered), or in a contrary direction to where the spinal marrow terminates.

XXIII. On the water-barometer erected in the hall of the Royal Society

1832 ◽  
Vol 122 ◽  
pp. 539-574 ◽  
Keyword(s):  
Royal Society ◽  
Physical Science ◽  
The Other ◽  
Metallic Tube ◽  
French Academy ◽  
History Of ◽  
The Subject ◽  
The Common ◽  
Academy Of Sciences ◽  
Made In

I have for some time entertained an opinion, in common with some others who have turned their attention tot he subject, that a good series of observations with a Water-Barometer, accurately constructed, might throw some light upon several important points of physical science: amongst others, upon the tides of the atmosphere; the horary oscillations of the counterpoising column; the ascending and descending rate of its greater oscillations; and the tension of vapour at different atmospheric temperatures. I have sought in vain in various scientific works, and in the Transactions of Philosophical Societies, for the record of any such observations, or for a description of an instrument calculated to afford the required information with anything approaching to precision. In the first volume of the History of the French Academy of Sciences, a cursory reference is made, in the following words, to some experiments of M. Mariotte upon the subject, of which no particulars appear to have been preserved. “Le même M. Mariotte fit aussi à l’observatoire des experiences sur le baromètre ordinaire à mercure comparé au baromètre à eau. Dans l’un le mercure s’eléva à 28 polices, et dans Fautre l’eau fut a 31 pieds Cequi donne le rapport du mercure à l’eau de 13½ à 1.” Histoire de I'Acadérmie, tom. i. p. 234. It also appears that Otto Guricke constructed a philosophical toy for the amusement of himself and friends, upon the principle of the water-barometer; but the column of water probably in this, as in all the other instances which I have met with, was raised by the imperfect rarefaction of the air in the tube above it, or by filling with water a metallic tube, of sufficient length, cemented to a glass one at its upper extremity, and fitted with a stop-cock at each end; so that when full the upper one might be closed and the lower opened, when the water would fall till it afforded an equipoise to the pressure of the atmo­sphere. The imperfections of such an instrument, it is quite clear, would render it totally unfit for the delicate investigations required in the present state of science; as, to render the observations of any value, it is absolutely necessary that the water should be thoroughly purged of air, by boiling, and its insinuation or reabsorption effectually guarded against. I was convinced that the only chance of securing these two necessary ends, was to form the whole length of tube of one piece of glass, and to boil the water in it, as is done with mercury in the common barometer. The practical difficulties which opposed themselves to such a construction long appeared to me insurmount­able; but I at length contrived a plan for the purpose, which, having been honoured with the approval of the late Meteorological Committee of this Society, was ordered to be carried into execution by the President and Council.

scholarly journals II. Compounds isomeric with the sulphocyanic ethers.—I. On the mustard oil of the ethyl series

1868 ◽  
Vol 16 ◽  
pp. 254-258
Keyword(s):  
Royal Society ◽  
The Other ◽  
Mustard Oil ◽  
Other Hand ◽  
Derivatives Of

The results of my researches on the chloroform-derivatives of the primary monamines, which, as I have shown, are isomeric with the nitriles, could not fail to direct my attention to allied groups of bodies, with the view of discovering similar isomerisms. In a note communicated to the Royal Society some months ago, I expressed the expectations which even then appeared to be justified in the following manner:—“In conclusion, I may be permitted to announce as everv probable the existence of a series of bodies isomeric with the sulphocyanides. Already M. Cloëz has shown that the action of chloride of cyanogen on ethylate of potassium gives rise to the formation of an ethylic cyanate possessing properties absolutely different from those belonging to the cyanate discovered by M. Wurtz. On comparing, on the other hand the properties of the methylic and ethylic sulphocyamdes with those of the sulphocyanides of allyl and phenyl, it can scarcely be doubted that we have here the representatives of two groups entirely different, and that the terms of the methyl- and ethyl-series which correspond to oil of mustard, and to the sulphocyanide of phenyl, still remain to be discovered. Experiments with which I am now engaged will show whether these bodies cannot be obtained by the action of the iodides of methyl and ethyl on sulphocyanide of silver."

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