Transfer and storage of vibrational energy in liquids: Liquid nitrogen and its solutions with carbon monoxide

1980 ◽  
Vol 73 (10) ◽  
pp. 4904-4913 ◽  
Author(s):  
David W. Chandler ◽  
George E. Ewing
2000 ◽  
Vol 65 (7) ◽  
pp. 1073-1081 ◽  
Author(s):  
Valerie Holubová ◽  
Iva Chvílíčková ◽  
Vlastimil Kubáň

Extraction procedures (steam distillation, supercritical fluid extraction and solvent extraction) for isolation of monoterpene hydrocarbons from fresh needles of Picea abies and Picea omorica were optimised. The procedures were compared with the aim of minimizing consumption of needles and improving the extraction efficiency and repeatability. An influence of homogenisation procedures and storage conditions (liquid nitrogen, -18 and 4 °C) on the total content and composition of essential oils was studied. Cryogenic grinding (liquid nitrogen) combined with the extraction with cold hexane (extraction time 2 h) and subsequent GC-MS determination in freshly homogenised needles gives the best results (1.5-4 times better extraction efficiency, RSD < 10% for P. abies and < 25% for P. omorica). Limits of detections (3 S/N) for individual monoterpene hydrocarbons from units to tens of ng/g and recoveries 97.2-101.4% were found in fresh needles (calculated to fresh weight). While cooling to 4 °C is unacceptable, freezing at -18 °C for the period of 18 days in the dark gives also good results.


2012 ◽  
Vol 476-478 ◽  
pp. 1336-1340
Author(s):  
Kai Feng Li ◽  
Rong Liu ◽  
Lin Xiang Wang

The concept of energy harvesting works towards developing self-powered devices that do not require replaceable power supplies. Energy scavenging devices are designed to capture the ambient energy surrounding the electronics and convert it into usable electrical energy. A number of sources of harvestable ambient energy exist, including waste heat, vibration, electromagnetic waves, wind, flowing water, and solar energy. While each of these sources of energy can be effectively used to power remote sensors, the structural and biological communities have placed an emphasis on scavenging vibrational energy with ferroelectric materials. Ferroelectric materials have a crystalline structure that provide a unique ability to convert an applied electrical potential into a mechanical strain or vice versa. Based on the properties of the material, this paper investigates the technique of power harvesting and storage.


Author(s):  
Lucia De Santis ◽  
◽  
Lodovico Parmegiani ◽  
Catello Scarica

Author(s):  
G.P. Morie ◽  
C.H. Sloan

AbstractA gas chromatographic method for the determination of carbon monoxide and carbon dioxide in cigarette smoke was developed. A column containing Porapak Q packing and a cryogenic temperature programmer which employed liquid nitrogen to cool the column to subambient temperatures was used. The separation of N


In the previous paper of this series it was shown :— (1) that when nitrogen is added as a diluent to a mixture of 2CO+O 2 undergoing combustion in a bomb at an initial pressure of 50 atmospheres, it exerts a peculiar energy-absorbing influence upon the system, far beyond that of other diatomic gases, or of argon; (2) that by virtue of such influence, it retards the attainment of maximum pressure in a much greater degree than can be accounted for on the supposition of its acting merely as a diatomic diluent; (3) that the energy so absorbed by the nitrogen during the combustion period, which extends right up to the attainment of maximum pressure, is slowly liberated thereafter as the system cools down ; and that consequently the rate of cooling is greatly retarded for a considerable time interval after the attainment of maximum pressure; (4) that there is no such energy-absorbing effect ( i. e ., other than a purely "diluent" one) when nitrogen is present in a 2H 2 +O 2 mixture similarly undergoing combustion ; but that, on the contrary, the presence of hydrogen in a CO-air mixture undergoing combustion at such high pressures so strongly counteracts the said " energy-absorbing " influence of the nitrogen, that it must be excluded as far as possible from the system before any large nitrogen-effect can be observed. These facts were explained on the supposition that there is some constitutional correspondence between CO and N 2 molecules (whose densities are identical) whereby the vibrational energy (radiation) emitted when the one burns is of such a quality as can be readily absorbed by the other, the two thus acting in resonance. It was further supposed that, in consequence of such resonance, nitrogen becomes chemically " activated " when present during the combustion of carbon monoxide at such high pressures ; and in conformity with this supposition, it was shown that such "activated" nitrogen is able to combine with oxygen more readily than does nitrogen which has merely been raised to a correspondingly high temperature in a hydrogen-air explosion.


1979 ◽  
Vol 15 (9) ◽  
pp. 973-974
Author(s):  
S. Akhmanov ◽  
F. Gadjiev ◽  
N. Koroteev ◽  
R. Orlov ◽  
I. Shumay

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