Light Emission and Absorption Spectroscopic Study of HCCI Combustion

2009 ◽  
Author(s):  
Akira Iijima ◽  
Koji Yoshida ◽  
Hideo Shoji
2012 ◽  
Author(s):  
Mitsuo Asanuma ◽  
Akira Iijima ◽  
Koji Yoshida ◽  
Hideo Shoji ◽  
Go Emori

2017 ◽  
Vol 122 (1) ◽  
pp. 839-849 ◽  
Author(s):  
Annamaria Panniello ◽  
A. Evelyn Di Mauro ◽  
Elisabetta Fanizza ◽  
Nicoletta Depalo ◽  
Angela Agostiano ◽  
...  

Author(s):  
Akira Iijima ◽  
Hideo Shoji

The principal issues of Homogeneous Charge Compression Ignition (HCCI) combustion that must be addressed include ignition timing control and expansion of the stable operation region. Detailed analyses of ignition and combustion mechanisms must be undertaken to resolve these issues. In this study, spectroscopic technique was used to investigate the effects of the air-fuel ratio (AFR) and residual gas state on ignition and combustion characteristics. Spectroscopic measurement was made of light emission spectra. The results revealed that the distribution profile of the light emission intensity of the hot flame differed substantially depending on the air-fuel ratio (AFR). In high AFR condition, a continuous spectrum attributed to carbon monoxide-oxygen (CO-O) glow is seen between 300–500 nm, but there is no strong light emission such as that from the OH radical. However, decreasing the AFR, a strong light emission is seen a little after the CO-O glow in a wavelength range from visible light to the near-infrared region (500–850 nm). It is also clear that increasing the internal EGR declined the cool flame magnitude, which substantially altered the ignition characteristics of HCCI combustion. Specifically, when a low-octane fuel was used, the heat release rate waveform for HCCI combustion showed two-stage ignition, which was clearly observed in the light emission spectra.


1965 ◽  
Vol 5 ◽  
pp. 120-130
Author(s):  
T. S. Galkina

It is necessary to have quantitative estimates of the intensity of lines (both absorption and emission) to obtain the physical parameters of the atmosphere of components.Some years ago at the Crimean observatory we began the spectroscopic investigation of close binary systems of the early spectral type with components WR, Of, O, B to try and obtain more quantitative information from the study of the spectra of the components.


Author(s):  
Ben O. Spurlock ◽  
Milton J. Cormier

The phenomenon of bioluminescence has fascinated layman and scientist alike for many centuries. During the eighteenth and nineteenth centuries a number of observations were reported on the physiology of bioluminescence in Renilla, the common sea pansy. More recently biochemists have directed their attention to the molecular basis of luminosity in this colonial form. These studies have centered primarily on defining the chemical basis for bioluminescence and its control. It is now established that bioluminescence in Renilla arises due to the luciferase-catalyzed oxidation of luciferin. This results in the creation of a product (oxyluciferin) in an electronic excited state. The transition of oxyluciferin from its excited state to the ground state leads to light emission.


Author(s):  
C. Jacobsen ◽  
J. Fu ◽  
S. Mayer ◽  
Y. Wang ◽  
S. Williams

In scanning luminescence x-ray microscopy (SLXM), a high resolution x-ray probe is used to excite visible light emission (see Figs. 1 and 2). The technique has been developed with a goal of localizing dye-tagged biochemically active sites and structures at 50 nm resolution in thick, hydrated biological specimens. Following our initial efforts, Moronne et al. have begun to develop probes based on biotinylated terbium; we report here our progress towards using microspheres for tagging.Our initial experiments with microspheres were based on commercially-available carboxyl latex spheres which emitted ~ 5 visible light photons per x-ray absorbed, and which showed good resistance to bleaching under x-ray irradiation. Other work (such as that by Guo et al.) has shown that such spheres can be used for a variety of specific labelling applications. Our first efforts have been aimed at labelling ƒ actin in Chinese hamster ovarian (CHO) cells. By using a detergent/fixative protocol to load spheres into cells with permeabilized membranes and preserved morphology, we have succeeded in using commercial dye-loaded, spreptavidin-coated 0.03μm polystyrene spheres linked to biotin phalloidon to label f actin (see Fig. 3).


Author(s):  
Gisèle Nicolas ◽  
Jean-Marie Bassot ◽  
Marie-Thérèse Nicolas

The use of fast-freeze fixation (FFF) followed by freeze-substitution (FS) brings substantial advantages which are due to the extreme rapidity of this fixation compared to the conventional one. The initial step, FFF, physically immobilizes most molecules and therefore arrests the biological reactions in a matter of milliseconds. The second step, FS, slowly removes the water content still in solid state and, at the same time, chemically fixes the other cell components in absence of external water. This procedure results in an excellent preservation of the ultrastructure, avoids osmotic artifacts,maintains in situ most soluble substances and keeps up a number of cell activities including antigenicities. Another point of interest is that the rapidity of the initial immobilization enables the capture of unstable structures which, otherwise, would slip towards a more stable state. When combined with electrophysiology, this technique arrests the ultrastructural modifications at a well defined state, allowing a precise timing of the events.We studied the epithelium of the elytra of the scale-worm, Harmothoe lunulata which has excitable, conductible and bioluminescent properties. The intracellular sites of the light emission are paracrystals of endoplasmic reticulum (PER), named photosomes (Fig.1). They are able to flash only when they are coupled with plasma membrane infoldings by dyadic or triadic junctions (Fig.2) basically similar to those of the striated muscle fibers. We have studied them before, during and after stimulation. FFF-FS showed that these complexes are labile structures able to diffentiate and dedifferentiate within milliseconds. Moreover, a transient network of endoplasmic reticulum was captured which we have named intermediate endoplasmic reticulum (IER) surrounding the PER (Fig.1). Numerous gap junctions are found in the membranous infoldings of the junctional complexes (Fig.3). When cryofractured, they cleave unusually (Fig.4-5). It is tempting to suggest that they play an important role in the conduction of the excitation.


Agronomie ◽  
2003 ◽  
Vol 23 (8) ◽  
pp. 719-724 ◽  
Author(s):  
Giovanni Gigliotti ◽  
Alceo Macchioni ◽  
Cristiano Zuccaccia ◽  
Pier Lodovico Giusquiani ◽  
Daniela Businelli

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