scholarly journals XXIII. On the determination of the constants of the cup anemometer by experiments with a whirling machine

1878 ◽  
Vol 169 ◽  
pp. 777-822 ◽  
Keyword(s):  
Royal Society ◽  
The Other ◽  
Royal Irish Academy ◽  
Central Dome ◽  
Other Hand ◽  
Cup Anemometer

In a communication to the Royal Irish Academy (Proceedings of the Royal Irish Academy, December, 1875), in which I examined the experiments made by M. Dohrandt to determine the constants of the cup anemometer by means of Robins’ whirling machine, I expressed a hope that I might have an opportunity of making similar experiments free from some influence which seemed to me objectionable. This opportunity was soon afforded me by a liberal grant from the Donation Fund of the Royal Society. I lost no time in having the necessary apparatus constructed by Mr. Howard Grubb, of Dublin, and I now propose to give the results which I have obtained with it. (1.) I was at first embarrassed by the difficulty of finding a suitable locality for the machine. In the St. Petersburg experiments the anemometers passed in their rotation at unequal distances from the walls of the building, and were too near its roof, which seemed likely to introduce extra disturbances into the air vortex which is formed by the whirl of the machine, and which, as will be seen, is a notable element of uncer­tainty in these investigations. But this was removed by Mr. H. Grubb placing at my disposal the central dome of his works at Rathmines, then recently constructed for mounting the great equatorial which he is making for the Vienna Observatory. Its basis is a regular dodecagon, 42 feet least diameter, and 42 feet from its floor to the summit of the dome. Round it, at 10 feet from the ground, runs a gallery 2 feet wide, with a light iron railing, from which several doors give access to workshops in which polishing and other light work is executed. On the ground, open arches communicate with shops, in which large lathes and other heavy tools are established. This seemed all that I could wish, but, unfortunately, I could have the use of it only till the end of June, when it was wanted for the erection of the equatorial. There were, however, two inconveniences to be feared. One was that the open arches might admit irregular currents of air ; the other was that when heavy turning or planing was going on, tremors were produced in the ground which might be expected to make the friction of the apparatus vary. I supposed, however, that this disturbance would equally affect the motion of the anemometers and the measures of their frictions ; but this influence proved to be of far greater importance than I had anticipated. On the other hand, the vicinity of skilled workmen, ready to make any necessary repairs or any alteration suggested by my experiments, was of great importance, and not less so the help which Mr. Grubb and his assistant, Mr. Vereker, gave me during the whole of this work.

scholarly journals II. On the determination of the constants of the cup anemometer by experiments with a whirling machine

1878 ◽  
Vol 27 (185-189) ◽  
pp. 286-289 ◽  
Keyword(s):  
Royal Society ◽  
Concave Surface ◽  
Royal Irish Academy ◽  
Limited Scale ◽  
Cup Anemometer

In his description of the cup anemometer (Transactions Royal Irish Academy, Vol. XXII), Dr. Robinson inferred from experiments on a very limited scale with Robins’ whirling machine, that the ultimate ratio of the wind’s velocity to that of the centre of the cups =3. Some recent experiments by M. Dohrandt show that this number is too great; but as some of the details appeared objectionable, and as they did not include all the necessary data for determining the constants, the author was desirous of repeating them. He was enabled to do this by a liberal grant from the Royal Society, and the results are given in this paper. After describing the apparatus and the locality in which it was established, he proceeds to explain the conditions of an anemometer’s action. Considering only two opposite cups, and supposing them in motion, the pressure on the concave surface is as that surface and the square of the resultant of the wind’s velocity V and v , that of the anemometer, and as a , the pressure of an unit V on the cup normal to the arm.

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."

scholarly journals Determination of the Ratios of Ligands to Metal Ion of some Metal Complexes of Triazoles by Using Eleetronie Speetra in Organie Solvents

2004 ◽  
Vol 1 (1) ◽  
pp. 110-115
Author(s):  
Baghdad Science Journal
Keyword(s):  
Solid State ◽  
Metal Complexes ◽  
Electronic Spectra ◽  
Metal Ion ◽  
The Other ◽  
Molar Ratio ◽  
Other Hand

We found that 4,5- diphenyl- 3(2- propynyl) thio- 1??-triazole [1? forms a complex with Pd (11) ion of ratio 1:1 which absorbs light in CH2CI2 at 400 nm, and 4,5- diphenyl- 3(2- propenyl) thio- 1,2,4- triazole [II] forms complexes with Pd (II) ion of ratio 1:1 which absorbs light at 390 nm, and of ratio 2:1 which absorbs light at 435 nm. On the other hand, we found that the new derivative 4- phenyl- 5( p- amino phenyl) -3- mercapto- 1,2,4- triazole ?111? forms complexes with Cu (II) ion of the ratio 1:1 which absorbs light at 380 nm, with Ni (II) ion of the ratio 3:1 which absorbs light at 358 nm; and with Co (11) ion of the ratio 3.2:1 which absorbs light at 588 nm. The ratio of the complexes were determined by measuring the electronic spectra of the complexes in CH2G2 and (CH^NCHO at different concentrations ofthe ligands and f?xed ' •' of the metal ion in every case, then applying the molar ratio plots on the data. Our results were confirmed by precipitating most ofthe above complexes in solid state, and then each complex was analyzed elementally.

scholarly journals Resin canals in spruce (Picea abis /L./ Karst.) with the occurrence of reaction wood

2005 ◽  
Vol 53 (1) ◽  
pp. 85-92 ◽  
Author(s):  
Vladimír Gryc ◽  
Petr Horáček
Keyword(s):  
Compression Wood ◽  
3D Models ◽  
Resin Canal ◽  
The Other ◽  
Stem Length ◽  
Reaction Wood ◽  
Spruce Wood ◽  
Other Hand ◽  
Resin Canals

The paper was aimed at the determination of variability of horizontal resin canal dimension in spruce wood in relation to the position in a spruce stem. Significant changes of dimensions in horizontal resin canal along the stem length and radius were found. On the basis obtained of results 3D models (for CW, OW, SWL and SWP zones) describing changes in resin canal dimensions in spruce in relation to the position in a stem were created. In the models, the resin canal dimension decreases with the height of a stem and on the other hand, with an increasing distance from the stem pith the dimension of resin canal increases. The importance of the paper consists in the enlargement of findings about the structure of spruce with compression wood.

Kvalitet pitanja u TV školi u nastavi prirode i društva

2021 ◽  
Author(s):  
Jelena Lukić ◽  
Keyword(s):  
Social Science ◽  
The Other ◽  
Educational Content ◽  
Educational Levels ◽  
School Year ◽  
Other Hand ◽  
Cognitive Levels ◽  
The Way

The aim of this paperis to determine the quality of TV classes World around us and Nature and Social Science,which were broadcasted on Radio Television of Serbia during the pandemic in the school year 2019/20. Although the work was indirect, so the immediate interaction between the teacher and student is missed. Therefore, teacher's questions were the way of establishing some kind of interaction in such classes organized in this manner. For this reason, we wanted to establish the types of questions that teachers were asking to students through small screens. Considering that the achievements of learning are based on Bloom's Taxonomy, we were analyzing sixteen TV classes and classified the questions the teachers asked according to cognitive area, on six educational levels. The results indicate that the most common were question within lower cognitive levels were (knowledge, understanding and application), and that there are no statistically significant differences in cognitive levels on questions asked between lower (1st and 2nd grade) and higher grades (3rd and 4th grade), on the other hand, on the classes of determination of educational content teachers were asking statistically significant quality questions compared to the classes of interpretation.

“ Ten Years' Testing of Model Seaplanes ”

1923 ◽  
Vol 27 (149) ◽  
pp. 224-243
Author(s):  
G. S. Baker
Keyword(s):  
Experimental Work ◽  
Royal Society ◽  
General Meeting ◽  
National Physical Laboratory ◽  
The Other ◽  
Experimental Tank ◽  
Know How ◽  
Other Hand ◽  
Physical Laboratory ◽  
Hull Design

An Ordinary General Meeting- of the Society was held at the Royal Society of Arts, on Thursday, February ist, 1923, Professor L. Bairstow in the chair.The Chairman, in opening- the proceedings, said that Mr. G. S. Baker, O.B.E., of the National Physical Laboratory, would deal with flying boats and seaplanes. He would deal with the hull and its design, that part of the seaplane which differentiates it from the aeroplane. That subject had been touched on very lightly by Major Rennie at the previous meeting of the Society, in view of the present paper by Mr. Baker.Mr. Baker had begun work in 1912 on the problems of hull design, at a time when nothing of a definite nature was known; a few individual experiments had been carried out, but there was no systematised knowledge at all at that time. From that state of ignorance a great deal of experimental work had now rescued us. He did not know how far Mr. Baker would stress the point, but it was quite clear, from the investigation of certain accidents to seacraft, that there were fundamental differences in the behaviour of seaplane hulls on the water, differences which had a great deal of effect on the risk of flying-. For instance, if one type of hull was such that when the plane rose in the air it stalled, then all the aerodynamical consequences of stalling- followed, and there was difficulty. On the other hand, it appeared that we had a type of flying- boat which did not make the plane stall on getting into the air, and consequently if it came back to the water it was still controlled. For this type of development, which he believed really dated back to the C.E.i, we were mainly indebted to Mr. Baker and his associates at the National Physical Laboratory, and to the generosity of Sir Alfred Yarrow in placing such a magnificent piece of apparatus as the experimental tank at the disposal of the nation.Mr. Baker then read his paper on “ Ten Years’ Testing of Model Seaplanes.”

scholarly journals XIII. Revision of the atomic weight of gold

1889 ◽  
Vol 180 ◽  
pp. 395-441 ◽  
Keyword(s):  
Royal Society ◽  
Original Work ◽  
Atomic Weight ◽  
The Other ◽  
Organic Substances ◽  
Modern Methods ◽  
Gold Compounds ◽  
Chemical Section

Until lately gold ranked among the elementary substances of which the general properties had been well ascertained, but in regard to the atomic weights of which our knowledge was least satisfactory. That this constant should be determined as accurately as possible for gold was desirable in view of its bearing on the precise place assigned the metal in the “periodic” classification of the elements based on the ideas of Newlands, Odling, Mendelejeff, and L. Meyer. Furthermore, an exact know­ ledge of the atomic weight of gold might be conveniently applied in the determination of the atomic weights of some of the other elements. A practical laboratory reason for desiring to possess a trustworthy value for this constant was also presented by the facility with which gold compounds of many organic substances may be prepared, and the ease with which their composition may be ascertained by simple ignition in the air and weighing of the residual gold, the results leading to a knowledge of molecular composition when the atomic value of the weight of the metal obtained is assumed to be known. For the last three years and a half I have been occupied, during a large part of such time as has been available for original work, in devising and carrying out experiments aiming at the redetermination of the constant in question. The difficulties met with have been greater than were at first looked for, and have led to much time and labour being consumed in attempts to overcome them. About two years ago, when this work was already well under way but still in progress, there appeared the results of experiments aiming at the same end, by Kruss in Germany and by Thorpe and Laurie in England—experiments made with the care and accu­racy of modern methods, and apparently deserving of much confidence. My own work, however, was continued, as we cannot have too many careful independent determinations of atomic weights by different workers, and as I had used to a con­siderable extent other procesess than those on which the newly published determina­tions were based, while the chemists named had employed, in the main, one and the same method. A preliminary notice of my work was read in the Chemical Section of the British Association at the Manchester meeting of 1887. The details of my experiments and the results which I have reached are now laid before the Royal Society.

scholarly journals Markov chains and the determination of fair premiums

1967 ◽  
Vol 4 (3) ◽  
pp. 265-268 ◽  
Author(s):  
Stefan Vajda
Keyword(s):  
Stochastic Process ◽  
Markov Chains ◽  
Stochastic Processes ◽  
Mathematical Theory ◽  
The Other ◽  
Main Stream ◽  
Other Hand ◽  
Pure Mathematics ◽  
The University

The relationships between actuarial and pure mathematics are curious. Actuaries have contributed to the development of mathematical theory: it is sufficient to mention, as examples, Fredholm of an earlier, and Cramér of a more recent generation. Scandinavian mathematicians, in particular, have been concerned with a very special type of stochastic process, reflected in the collective theory of risk, and the work of Philipson, Ammeter and others in this field is well known to readers of this Bulletin. However, the main stream of the theory of stochastic processes has little contact with actuarial applications.On the other hand, many actuaries have studied and assimilated pure mathematics and have thrown light on actuarial matters by describing their own preoccupations in the terminology of modern, often abstract, mathematics. E. Franckx is one of their number.The Instituto di Matematica Finanziaria of the University of Trieste (Faculty of Economics and Commerce) has published a booklet entitledEssai d'une théorie opérationnelle des risques Markoviens which contains three lectures delivered by Professor Franckx in Trieste and a contribution which he presented to the 17th Congress of Actuaries, held in London in 1964.

scholarly journals XXVIII. On the forces caused by the communication of heat between a surface and a gas; and on a new photometer

1876 ◽  
Vol 166 ◽  
pp. 725-735 ◽  
Keyword(s):  
Kinetic Theory ◽  
Solid Surface ◽  
Royal Society ◽  
The Other ◽  
Other Hand ◽  
Careful Investigation ◽  
The Way

In a paper read before the Royal Society, April 1874, I pointed out that the communication of heat from a solid surface to a gas, whether accompanied by evaporation or not, must, according to the kinetic theory, be attended by a reactionary force equi­valent to an increase in the pressure of the gas on the surface, and, conversely, when heat is communicated from the gas to the surface the pressure against the surface is diminished; and I also suggested that these forces are the probable cause of the motion, resulting in some way from radiation, which Mr. Crookes had brought into such pro­minent notice. Since the publication of this paper neither my conclusions as to the existence of these “heat reactions,” nor the reasoning by which I supported them, have been controverted or even questioned; but, on the other hand, they have received important confirmation. The results at which Professors Tait and Dewar arrived after a careful investigation fully bear out my conclusions, not only as to the existence of the forces, but also as to the way in which they explain Mr. Crookes’s experiments.

Dermatoglyphics in Twins

1973 ◽  
Vol 22 (1) ◽  
pp. 91-98 ◽  
Author(s):  
Heloisa F. Peña ◽  
F.M. Salzano ◽  
Sidia M. Callegari
Keyword(s):  
Correlation Coefficients ◽  
The Other ◽  
Ridge Count ◽  
Genetic Determination ◽  
Qualitative Traits ◽  
Quantitative Measurements ◽  
Other Hand ◽  
Adult Twins

SummaryThe degree of genetic determination of 4 digital and 16 palmar characteristics was investigated in an unselected series of 49 MZ and 51 DZ adult twins. Low indications of heritability were obtained for the qualitative traits, but 6 of the 8 h2 estimates calculated for the quantitative measurements gave values above 0.70. In general, the results reported here are in agreement with those presented by other authors; however, the correlation coefficients observed for the A′d ridge count were lower than those of two other series. All palmar ridge counts seemed to be intercorrelated in a given individual; other expected relationships, however, were not observed. The fingerprints of MZ and DZ twins on the other hand, showed an unexplained difference.

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