The diffraction of light by high frequency sound waves. Part III. Doppler effect and coherence phenomena

The theory developed in part I of this series of papers has been developed in this paper to find the Doppler effects in the diffraction components of light produced by the passage of light through a medium containing (1) a progressive supersonic wave and (2) a standing supersonic wave. (1) In the case of the former the theory shows that the nth order which is inclined at an angle sin-1 (-nλ/λ∗) to the direction of the propagation of the incident light has the frequency ν-nν∗ where ν is the frequency of light, ν∗ is the frequency of sound and n is a positive or negative integer and that the nth order has the relative intensity J2n(2πμL/λ) where μ is the maximum variation of the refractive index, L is the distance between the faces of the cell of incidence and emergence and λ is the wavelength of light. (2) In the case of a standing supersonic wave; the diffraction orders could be classed into two groups, one containing the even orders and the other odd orders; any even order, say 2n, contains radiations with frequencies ν±2rν∗ where r is an integer including zero, the relative intensity of the ν±2rν∗ sub-component being J2n-r(πμL/λ) J2n+r(πμL/λ); and odd order, say 2n+1, contains radiations with frequencies ν ± 2r+1̅ν∗, the relative intensity of the ν ± 2r+1̅ν∗ sub-component being J2n-r , (πμL/λ) J2n+r+1(πμL/λ). These results satisfactorily interpret the recent results of Bar that any two odd orders or even ones partly cohere while an odd one and an even one are incoherent

The diffraction of light by sound waves of high frequency. Part II

The theory of the diffraction of light by sound waves of high frequency developed in our earlier paper is extended to the case when the light beam is incident at an angle to the sound wave-fronts, both from a geometrical point of view and an analytical one. It is found that the maxima of intensity of the diffracted light occur in directions which make definite angles, denoted by θ, with the direction of the incident light given by sin(θ+Φ) - sin Φ = ±[(nλ)/(λ∗ )], n (an integer) ≥ 0 where λ and λ∗ are the wave-lengths of the incident light and the sound waves in the medium. The relative intensity of the mth order to the nth order is given by Jm2( ν0 secΦ[(sint)/t] ) / Jn2 ( ν0 secΦ[(sint)/(t)]) where ν0=2πμL /λ,t=πL tanΦ/λ∗, Φ is the inclination of the incident beam of light to the sound waves, μ is the maximum variation of the refractive index in the medium when the sound waves are present and L secΦ is the distance of the light path in the medium. These results explain the variations of the intensity among the various orders noticed by Debye and Sears for variations of Φ in a very gratifying manner

The two types of X-ray reflection in crystals

The new type of X-ray reflection forming the subject of this paper was first described and an explanation of it on the basis of the quantum theory given in a series of papers published earlier this year by Raman and Nilakantan in these Proceedings and elsewhere. The present report is intended to be a self-contained theoretical exposition of the subject and incorporates the ideas already expounded in the papers by Raman and Nilakantan, as also the fuller mathematical treatment by Raman and Nath published in these Proceedings for July 1940. Recent experiments by Nilakantan with diamond completely establish the quantum theoretical explanation of the phenomenon

An expedient route for the reduction of carboxylic acids to alcohols employing 1-propanephosphonic acid cyclic anhydride as acid activator

A simple and efficient method for the synthesis of alcohols from the corresponding carboxylic acids is described. Activation of carboxylic acid with 1-propane phosphonic acid cyclic anhydride (T3P) and subsequent reduction of the intermediate phosphonic anhydride with NaBH 4 yield the alcohol in excellent yields with good purity in less duration. Reduction of several alkyl/aryl carboxylic acids and N α-protected amino acids/peptide acids as well as N β-protected amino acids was successfully carried out to obtain corresponding alcohols in good yields and the products characterized. The procedure is mild, safe, simple and the isolation of the products is easy. © 2012 Elsevier Ltd. All rights reserved

Changes in nitrate and nitrite levels of blanched amaranthus during refrigeration storage.

Changes in nitrate and nitrite contents (leaves and stem) of Amaranthus gangeticus (AG) and Amaranthus paniculatus (AP), resulting from blanching, storage time (0-4 days), storage temperature (0 and 4ºC), and reheating were analysed. Results showed that fresh AG (1859 ± 7.07 mg/kg) had higher nitrite content than AP (1262 ± 2.12 mg/kg). Nitrites content was 506 ± 2 and 825 ± 3.5 mg/kg for AG and AP, respectively. Reheating and storage times significantly increased the conversion of nitrate to nitrite in AG and AP. Storage at 0 and 4oC exhibited a significant change (P < 0.05) in nitrate and nitrite contents for both samples. Higher nitrite content was found in AP when stored at 4oC and 0oC. The present study indicated that storage time and temperature affected the nitrite contents in blanched AG and AP when stored in low temperatures. Apart from that reheating was also found to increase the formation of nitrite

Quantification of execution and emission efficiency of a fueled diesel engine

A significant portion of the automobile and industrial sector is mostly dependent on the running of diesel engines as it is efficient and shifts a large of the goods around the globe and power various equipment. Also, as the use of energy as diesel fuel is increasing enormously with the expansion of industrial growth, diversification, this led to the accelerating global emissions, global climatic change, health issues, and exhaustion of fuels. To succumb this, alternative fuel is needed to fight against the ill effects and as a replacement to diesel fuel. Thus, vegetable oils as alternative fuels are drawing more attention as they are renewable and do not address the problem of greenhouse gas. In the present work, the cottonseed oil was chosen as the favorite among the vegetable oils due to its advantages like less pollutant level, excessive availability, etc. The transesterification process was used to produce the cottonseed oil biodiesel. This research aims to investigate efficiency, emission characteristics by using smooth diesel, cottonseed oil, and mixtures with varying composition from 20 % to 80 % in 20 % steps to identify sustainable fuel as a substitute for existing fuel and to overcome fuel demand and enviro effects. This test was conducted on single-cylinder four-stroke water-cooled diesel engines. From the results, it was revealed that cottonseed oil and its blends have a significant influence on performance and emission characters

1-Chloro-4-(3,4-dichloro­phen­yl)-3,4-dihydro­naphthalene-2-carbaldehyde

The title compound, C17H11Cl3O, was synthesized via the Vilsmeier–Haack reaction. The dihydro­naphthalene ring system is non-planar, the dihedral angle between the two fused rings being 10.87 (13)°; it forms a dihedral angle of 81.45 (10)° with the dichloro­phenyl ring. The crystal structure features inter­molecular C—H⋯O hydrogen bonds