At double-line junctions trains passing over the diamond crossings evidently block traffic going in the opposite direction to that in which they are travelling.
Complications follow upon this in other forms. Even in Mytilus and Arca a connexion is here and there formed between the ascending and descending rami of a filament by hollow extensible outgrowths called " interlamellar junctions " (il.
If A and Bare constant, the Peltier effects at the hot and cold junctions are equal and opposite, and may therefore be neglected.
The centres of the cotton trade are Hubli and Gadag, junctions on the Southern Mahratta railway, which traverses the district in several directions.
The same arrangement is employed at junctions where different running lines converge.
In Great Britain the Board of Trade requires facing points to be avoided as far as possible; but, of course, they are a necessity at junctions where running lines diverge and at the crossing places which must be provided to enable trains to pass each other on single-track lines.
Thus the defects, whether of this secretion or of that, and again of motor activity, the state of the valvular junctions, the volume of the cavities, and their position in the abdomen, may be ascertained, and dealt with as far as may be; so that, although the fluctuations of chemical digestion are still very obscure, the application of remedies after a mere traditional routine is no longer excusable.
The microscope shows that the neighbouring filaments are held together by patches of cilia, called " ciliated junctions," which interlock with one another just as two brushes may be made to do.
12) give place to solid permanent inter-filamentar junctions, so that the filaments are converted, as it were, into a trellis-work.
Then let us suppose that the inter-lamellar junctions already noted in Mytilus become very numerous, large and irregular; by them the two trellis-works of filaments would be united so as to leave only a sponge-like set of spaces between them.
A,Part of four filaments seen from the outer face in order to show the ciliated junctions c.j.
B,Diagram of the posterior face of a single complete filament with descending ramus and ascending ramus ending in a hook-like process;ep.,ep.,the ciliated junctions; il,j ., inter-lamellar junction.
Classification Of Lamellibranchia The classification originally based on the structure of the gills by P. Pelseneer included five orders, viz.: the Protobranchia in which the gill-filaments are flattened and not reflected; the Filibranchia in which the filaments are long and reflected, with non-vascular junctions; the Pseudo-lamellibranchia in which the gill-lamellae are vertically folded, the interfilamentar and interlamellar junctions being vascular or non-vascular; the Eulamellibranchia in which the interfilamentar and interlamellar junctions are vascular; and lastly the Septibranchia in which the gills are reduced to a horizontal paltition.
Branchial filaments united by vascular interfilamentar junctions and vascular interlamellar junctions; the latter contain the afferent vessels.
The temperature at different heights was measured by iron wires forming thermo-junctions with the mercury in the inner tube.
The chief difficulty, as usual, was the determination of the gradient, which depended on a difference of potential of the order of 20 microvolts between two junctions inserted in small holes 2 cms. apart in a bar 1 .
The Central Wales section of the London & North-Western railway from Craven Arms to Swansea crosses the north-west corner of the county, and is intersected at Builth Road by a branch of the Cambrian, which, running for the most part on the Radnorshire side of the Wye, follows that river from Rhayader to Three Cocks; the Midland railway from Hereford to Swansea runs through the centre of the county, effecting junctions at Three Cocks with the Cambrian, at Talyllyn with the Brecon & Merthyr railway (which connects the county with the industrial areas of East Glamorgan and West Monmouthshire), and at Capel Colbren with the Neath and Brecon line.
In Sambas, Montrado and some parts of Pontianak, the greater density of the population is due to the greater fertility of the soil, the opening of mines, the navigation and trade plied on the larger rivers, and the concentration of the population at the junctions of rivers, the mouths of rivers and the seats of government.
Besides the junctions at Suczawa and Verciorova, the Rumania system meets the Hungarian through the Gyimes, Rothenthurm and Vulkan Passes; the Russian by lines from Jassy and Galatz to Kishinev in Bessarabia; the Bulgarian and Servian by means of numerous] ferries.
In series in the order, 1000, 100, 10, i; 1, 10, 100, 1000, the junctions between each pair being connected to brass blocks, a series of which are mounted upon an ebonite slab that forms the lid of the box.
But his name will always be associated with the thermal effects at junctions in a voltaic circuit.
Seebeck (1822), employing a galvanometer then recently invented, which was more suited for the detection of small electromotive forces, found that a current was produced if the junctions of the two metals were at different temperatures.
We have also in any case the relations (41) (42) (43) of the current, C, for any given pair of metals, was found to vary directly as the difference of temperature, t-t', between the hot and cold junctions, and inversely as the resistance, R, of the circuit.
- The limiting value, dE/dt, of the coefficient, p, for an infinitesimal difference, dt, between the junctions is called the Thermoelectric Power of the couple.
More accurately it may be stated that the thermoelectromotive force in any given circuit containing a series of different metals is a function of the temperatures of the junctions only, and is independent of the distribution of the temperature at any intermediate points, provided that each of the metals in the series is of uniform quality.
The junctions of the magnetic and the non-magnetic steel are therefore at different temperatures if the flame is moved, and a current is produced just as if a piece of different metal with junctions at different temperatures had been introduced into the circuit.
In the circuit, provided that the two junctions with the metal introduced are kept at the same temperature.
This law is commonly applied in connecting a thermocouple to a galvanometer with coils of copper wire, the junctions of the copper wires with the other metals being placed side by side in a vessel of water or otherwise kept at the same temperature.
If C is the intensity of the current through a simple thermocouple, the junctions of which are at temperatures t and 1', a quantity of heat, P X C, is absorbed by the passage of the current per second at the hot junction, t, and a quantity, P X C, is evolved at the cold junction, t'.
Consider an elementary couple of two metals A and B for which s has the values s and s" respectively, with junctions at the temperature T and T+dT (absolute), at which the coefficients of the Peltier effect are P and P+dP. Equating the quantity of heat absorbed to the quantity of electrical energy generated, we have by the first law of thermodynamics the relation dE/dT =dP/dT+(s' - s").
He enclosed various metallic junctions in a Bunsen ice calorimeter, and observed the evolution of heat per hour with a current of about 1.6 amperes in either direction.
4, which is given as an illustration, the cold junctions are supposed to be at o° C. and the hot junctions at 100° C. Noll's values (Table I.) are taken for the E.M.F., and it is supposed that the coefficient of the Thomson effect is zero in lead, i.e.
As located entirely in the conductors themselves, and not at all at the junctions, if p or (p" - p) is the difference of the E.M.F.s per degree in corresponding elements of the two metals.
In this case, however, in order to account for the phenomenon of the Peltier effect at the junctions, it is necessary to suppose that there is a real convection of heat by an electric current, and that the coefficient P or pT is the difference of the quantities of heat carried by unit quantity of electricity in the two metals.