scholarly journals XV. On the connexion between the phenomena of the absorption of light, and the colours of thin plates

1837 ◽  
Vol 127 ◽  
pp. 245-252 ◽  
Keyword(s):  
Narrow Range ◽  
Great Majority ◽  
Thin Plates ◽  
Third Order ◽  
The Third ◽  
John Herschel ◽  
Absorption Of Light ◽  
Series Of Experiments ◽  
General Opinion ◽  
Material Substances

Since the phenomena of the absorption of light by coloured media began to be studied with attention, various philosophers have regarded them as inexplicable by the theory of the colours of thin plates, and have consequently regarded Sir Isaac Newton’s theory of the colours of natural bodies as either defective in generality, or altogether unfounded. Mr. Delaval was the first person who brought an extensive series of experiments to bear upon this subject. Dr. Thomas Young considered it “impossible to suppose the production of natural colours perfectly identical with those of thin plates,” unless the refractive density of the particles of colouring bodies was at least twenty or thirty times as great as that of glass or water, which he con­sidered as “difficult to believe with respect to any of their arrangements constituting the diversities of material substances.” Sir John Herschel has expressed a still more decided opinion upon this subject. He regards “the speculations of Newton on the colours of natural bodies” as only “a premature generalization,” and "limited to a comparatively narrow range; while the phenomena of absorption, to which he considers the great majority of natural colours as referable, have always appeared to him to constitute a branch of photology sui generi .” The general opinion advanced by these three philosophers I have long entertained; and with the view of supporting them I have analysed a great variety of colours which are exhibited by the juices of plants. In a paper "On the Colours of Natural Bodies,” I have shown that the green colour of plants, the most prevalent of all the colours of natural bodies, in place of being a green of the third order , as Newton and his com­mentators assert, is a colour of no order whatever, and having in its composition no relation at all to the colours of thin plates.

scholarly journals The kinetics of the combination of hydrogen and oxygen

1928 ◽  
Vol 118 (779) ◽  
pp. 170-183 ◽  
Keyword(s):  
Gas Phase ◽  
Constant Temperature ◽  
Catalytic Reaction ◽  
Chemical Change ◽  
Third Order ◽  
Fundamental Interest ◽  
The Third ◽  
Series Of Experiments ◽  
Kinetics Of

Although there are few gaseous reactions of more fundamental interest than the union of hydrogen and oxygen, it can hardly be said that the kinetics of this combination are at all completely understood. Many investigations have been made of the catalytic reaction which occurs in contact with various surfaces, and of the phenomena accompanying the production of flame or explosion in the gas. Little is known about the conditions governing the rate of the actual chemical change in the gas phase, because although flames and explosions depend very much upon these they are determined by a great many other factors as well. In 1899 Bodenstein, following up some work initiated by Victor Meyer, made a long series of experiments by streaming mixtures of the two gases through porcelain vessels, heated to a constant temperature, and then analysing the products. He came to the conclusion that the reaction is of the third order, following the equation d [H 2 O]/ dt = k [H 2 ] 2 [O 2 ]. Since the rate of combination was very different in different vessels, he inferred that the reaction was taking place almost entirely on the surface of the vessel.

Probe size and 5th-order aberration

1987 ◽  
Vol 45 ◽  
pp. 134-135 ◽  
Author(s):  
Zhifeng Shao
Keyword(s):  
Electron Probe ◽  
Spherical Aberration ◽  
Wave Length ◽  
Cylindrical Symmetry ◽  
Electron Wave ◽  
Third Order ◽  
The Third ◽  
Probe Radius ◽  
Small Probe ◽  
Probe Size

A small electron probe has many applications in many fields and in the case of the STEM, the probe size essentially determines the ultimate resolution. However, there are many difficulties in obtaining a very small probe.Spherical aberration is one of them and all existing probe forming systems have non-zero spherical aberration. The ultimate probe radius is given byδ = 0.43Csl/4ƛ3/4where ƛ is the electron wave length and it is apparent that δ decreases only slowly with decreasing Cs. Scherzer pointed out that the third order aberration coefficient always has the same sign regardless of the field distribution, provided only that the fields have cylindrical symmetry, are independent of time and no space charge is present. To overcome this problem, he proposed a corrector consisting of octupoles and quadrupoles.

Children’s Recall of Approximations to English

1973 ◽  
Vol 16 (2) ◽  
pp. 201-212 ◽  
Author(s):  
Elizabeth Carrow ◽  
Michael Mauldin
Keyword(s):  
Language Development ◽  
Fourth Order ◽  
Third Order ◽  
Memory Processes ◽  
The Third ◽  
General Index ◽  
General Linguistic

As a general index of language development, the recall of first through fourth order approximations to English was examined in four, five, six, and seven year olds and adults. Data suggested that recall improved with age, and increases in approximation to English were accompanied by increases in recall for six and seven year olds and adults. Recall improved for four and five year olds through the third order but declined at the fourth. The latter finding was attributed to deficits in semantic structures and memory processes in four and five year olds. The former finding was interpreted as an index of the development of general linguistic processes.

scholarly journals Ultrafast Third-Order Nonlinear Optical Response Excited by fs Laser Pulses at 1550 nm in GaN Crystals

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3194
Author(s):  
Adrian Petris ◽  
Petronela Gheorghe ◽  
Tudor Braniste ◽  
Ion Tiginyanu
Keyword(s):  
Harmonic Generation ◽  
Nonlinear Optical ◽  
Laser Pulses ◽  
Third Harmonic Generation ◽  
High Repetition Rate ◽  
Third Order ◽  
Third Harmonic ◽  
The Third ◽  
High Repetition ◽  
Gan Crystal

The ultrafast third-order optical nonlinearity of c-plane GaN crystal, excited by ultrashort (fs) high-repetition-rate laser pulses at 1550 nm, wavelength important for optical communications, is investigated for the first time by optical third-harmonic generation in non-phase-matching conditions. As the thermo-optic effect that can arise in the sample by cumulative thermal effects induced by high-repetition-rate laser pulses cannot be responsible for the third-harmonic generation, the ultrafast nonlinear optical effect of solely electronic origin is the only one involved in this process. The third-order nonlinear optical susceptibility of GaN crystal responsible for the third-harmonic generation process, an important indicative parameter for the potential use of this material in ultrafast photonic functionalities, is determined.

Boundary-Value Problems for Third-Order Lipschitz Ordinary Differential Equations

2014 ◽  
Vol 58 (1) ◽  
pp. 183-197 ◽  
Author(s):  
John R. Graef ◽  
Johnny Henderson ◽  
Rodrica Luca ◽  
Yu Tian
Keyword(s):  
Differential Equation ◽  
Differential Equations ◽  
Ordinary Differential Equations ◽  
Boundary Value Problems ◽  
Order Differential Equation ◽  
Boundary Value ◽  
Point Boundary ◽  
Third Order ◽  
Optimal Length ◽  
The Third

AbstractFor the third-order differential equationy′″ = ƒ(t, y, y′, y″), where, questions involving ‘uniqueness implies uniqueness’, ‘uniqueness implies existence’ and ‘optimal length subintervals of (a, b) on which solutions are unique’ are studied for a class of two-point boundary-value problems.

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