If the fluctuations are irregular and non-periodic, teristics the sound is called a noise; if they are cyclic and follow a regular and sufficiently rapid periodic law, the sound is musical.
Deferring the detailed discussion of cyclic or ringed hydrocarbons, a correlation of the various types or classes of compounds which may be derived from hydrocarbon nuclei will now be given.
It will be seen that each type depends upon a specific radical or atom, and the copulation of this character with any hydrocarbon radical (open or cyclic) gives origin to a compound of the same class.
It may be noticed here that cyclic nuclei can only contain the groups > CH 2.
We proceed to consider various simple derivatives of the alcohols, which we may here regard as hydroxy hydrocarbons, R OH, where R is an alkyl radical, either aliphatic or cyclic in nature.
Cyclic Hydrocarbons and Nuclei.
Here we meet with a great diversity of types: oxygen, nitrogen, sulphur and other elements may, in addition to carbon, combine together in a great number of arrangements to form cyclic nuclei, which exhibit characters closely resembling open-chain compounds in so far as they yield substitution derivatives, and behave as compound radicals.
Zincke; and his researches have led to the discovery of many chlorinated oxidation products which admit of decomposition into cyclic compounds containing fewer carbon atoms than characterize the benzene ring, and in turn yielding openchain or aliphatic compounds.
During recent years an immense number of ringed or cyclic compounds have been discovered, which exhibit individual characters more closely resembling benzene, naphthalene, &c. than purely aliphatic substances, inasmuch as in general they contain double linkages, yet withstand oxidation, and behave as nuclei, forming derivatives in much the same way as benzene.
As a useful preliminary it is convenient to divide heterocyclic ring systems into two leading groups: (I) systems resulting from simple internal dehydration (or similar condensations) of saturated aliphatic compounds - such compounds are: the internal anhydrides or cyclic ethers of the glycols and thioglycols (ethylene oxide, &c.); the cyclic alkyleneimides resulting from the splitting off of ammonia between the amino groups of diaminoparaffins (pyrrolidine, piperazine, &c.); the cyclic esters of oxycarboxylic acids (lactones, lactides); the internal anhydrides of aminocarboxylic acids (lactams, betaines); cyclic derivatives of dicarboxylic acids (anhydrides, imides, alkylen-esters, alkylenamides, &c.).
The transition between the two classes as differentiated above may be illustrated by the following cyclic compounds, each of which contains a ring composed of four carbon atoms and one oxygen atom: CH CH/ CH CH/ CH CO I CH CO' CH =CH c Tetramethylene But yrolactone.
The associations of his home, not far from Corinth, where Arion was said to have established the cyclic choruses of satyrs, may account for his preference for this kind of drama.
Wallach (Ann., 1900, 312, p. 171) has shown that the saturated cyclic ketones yield oximes which by an application of the Beckmann reaction are converted into isoximes, and these latter on hydrolysis with dilute mineral acids are transformed into acyclic amino-acids; thus from cyclohexanone, e-amidocaproic acid (e-leucine) may be obtained: CH2" C NOH C CH 2 CH 2 7: ?12?CH2 CH2 NH /CH2 CH2 C02H CH2', An ingenious application of the fact that oximes easily lose the elements of water and form nitriles was used by A.
The cycle of Guillaume has more unity than the other great cycles of Charlemagne or of Doon de Mayence, the various poems which compose it forming branches of the main story rather than independent epic poems. There exist numerous cyclic MSS.
After a few repetitions of the reversal, the process becomes strictly cyclic, the upward and downward curves always following with precision the paths indicated in the figure.
In order to establish the cyclic condition, it is sufficient to apply alternately the greatest positive and negative forces employed in the test (greatest H=about ?5 C.G.S.
By the alternate application and withdrawal of a small magnetizing force a cyclic condition may be established in an iron rod.
In the latter case the first application of stress is always attended by an increase-often a very great one-of the magnetization, whether the field is weak or strong, but after a load has been put on and taken off several times the changes of magnetization become cyclic. From experiments of both classes it appears that for a given field there is a certain value of the load for which the magnetization is a maximum, the maximum occuring at a smaller load the stronger the field.
The effects of longitudinal pressure are opposite to those of traction; when the cyclic condition has been reached, pressure reduces the magnetization of iron in weak fields and increases it in strong fields (Ewing, Magnetic Induction, 1900, 223).
Became definite and cyclic. When the permanent magnetic condition had been thus established, it was found that in the case of all the metals, except the two alloys containing large percentages of nickel, the magnetic moment was temporarily increased by cooling to - 186°.
Rhoads obtained a cyclic curve for iron which indicated thermo-electric hysteresis of the kind exhibited by Nagaoka's curves for magnetic strain.
TRIAZINES, in organic chemistry, a series of cyclic compounds, containing a ring system composed of three carbon and three nitrogen atoms. Three series are possible, the positions of Marine Trias Of The Alpine And Indian Types.
Nanak seems to have been produced by the same cyclic wave of reformation as fourteen years later gave Martin Luther to Europe.
Thus, in (5), the cyclic constant k = 27rm.
But there is no evidence for his "cyclic date" of 2517 B.C., on which his system depended, and there is little doubt that the beginning of the historical period of Berossus is to be set, not in 2506 B.C., but in 2232 B.C. The two systems of Sayce,' that of Rogers,' the three systems of Winckler, 5 both those of Delitzsch, 6 and that of Maspero, 7 may be grouped together, for they are based on the same principle.
A dissolved in B and B dissolved in A, since both of these solutions emit vapours of the same composition (this follows since the same vapour must be in equilibrium with both solutions, for if it were not so a cyclic system contradicting the second law of thermodynamics would be realizable).
It is not improbable that it represents a free and individual working over of the original Fescamp version, and that in its later shape it was intended to form, and did at one time form, the Quest section of the cyclic redaction of the Arthurian prose romances, being dislodged from this position by the Galahad Quese.
The city was enriched with notable temples and public works (see § Archaeology), and became the home of several Cyclic poets and of Arlon, the perfecter of the dithyramb.
These brief allusions were elaborated by the "cyclic" poets, and the adventures of Philoctetes formed the subject of tragedies by Aeschylus, Sophocles and Euripides.
His materials are borrowed from the cyclic poems from which Virgil (with whose works he was probably acquainted) also drew, in particular the Aethiopis of Arctinus and the Little Iliad of Lesches.
It is true that the theory of vortex rings in hydrodynamics is of a simpler type; but electric currents cannot be likened to permanent vortex rings, because their circuits can be broken and the element of cyclic steadiness on which the simplicity depends is thereby destroyed.
It should be noted that Tristan is never more than superficially connected with Arthur, an occasional visitor at his court; though in its later form ranked among the Arthurian romances, the Tristan is really an independent story, and does not form a part of the ordinary cyclic redaction.
Many cyclic ketones are known, and in most respects they resemble the ordinary aliphatic ketones (see Polymethylenes; Terpenes).
The name Cycleus given to his father indicates the connexion of the son with the "cyclic" or circular chorus which was the origin of tragedy.
The terms affected with the coefficients ~3,-., on the other hand are such as occur in cyclic systems with latent motion (DYNAMICS, Analytical); they are called the gyrostatic terms. If we multiply (33) by 4~.
The same line of argument may be extended to the Hymns, and even to some of the lost works of the post-Homeric or so-called " Cyclic " poets.
Yet Arctinus of Miletus was said to have been a " disciple of Homer," and was certainly one of the earliest and most considerable of the " Cyclic " poets.
Authorship which is so common with other " Cyclic " poems. How has this come about?
The quotation from the Iliad is of interest because it is made in order to show that Homer supported the story of the travels of Paris to Egypt and Sidon (whereas the Cyclic poem called the Cypria ignored them), and also because the part of the Iliad from which it comes is cited as the " Aristeia of Diomede."
An examination of these arguments throws light on two chief aspects of the relation between Homer and his " cyclic " successors.
This conclusion he then supports by the character attributed to the " Cyclic " poems (whose want of unity showed that the structure of the Iliad and Odyssey must be the work of a later time), by one or two indications of imperfect connexion, and by the doubts of ancient critics as to the genuineness of certain parts.
Wolf had argued that if the cyclic writers had known the Iliad and Odyssey which we possess, they would have imitated the unity of structure which distinguishes these two poems. The result of Welcker's labours was to show that the Homeric poems had influenced both the form and the substance of epic poetry.
The tendency to amplify and complete the story shows itself still more in the Cyclic poets.
Noticed above between the Iliad and the Odyssey, and between Homer and the early Cyclic poems. And the peculiar degradation of Homeric characters which appears in some poets (especially Euripides) finds a parallel in the later chansons de geste.3 The comparison of Homer with the great literary epics calls for more discursive treatment than would be in place here.
Although originally described as acetylketen, it has proved to be a cyclic compound (Ber., 1909, 4 2, p. 4908).
With the fall of water there is an increase in the specific gravity, which in 1850 was 1.17, and in September 1901 was I 179; in 1850 the proportion of solids by weight was 22.282%, in September 1901 it was 25.221; at the earlier of these dates the solids in a litre of water weighed 260.69 grams, at the latter date 302'122 grams. The exact cause of this cyclic variation is unknown: the low level of 1906 is usually regarded as the result of extensive irrigation and ploughing in the surrounding country, which have robbed the lake, in part, of its normal supply of water.
Pyrocatechin readily condenses to form heterocyclic compounds; cyclic esters are formed by phosphorus trichloride and oxychloride, carbonyl chloride, sulphuryl chloride, &c.; whilst ortho-phenylenediamine, o-aminophenol, and o-aminothiophenol give phenazine, phenoxazine and thiodiphenylamine.
POLYMETHYLENES, in chemistry, cyclic compounds, the simplest members of which are saturated hydrocarbons of general formula C 7, H 2nj where n may be r to 9, and known as tri-, tetra-, penta-, hexa-, and hepta-methylene, &c., or cyclo- propane, -butane, -pentane, -hexane, -heptane, &c.: - CH 21 CH 2 CH 2 CH2.CH2 CH2 CH2 CH2?C1H,, I I H ?
Senderens, loc. cit.); by the reduction of cyclic esters with CH 2 CH2 / NCH2- -CHI sodium and alcohol (L.
Blanc, Comptes rendus, 1903, 136, p. 1676; 137, p. 60); and by the addition of the elements of water to the unsaturated cyclic hydrocarbons on boiling with dilute acids.