MASS SPECTROGRAPHIC DETECTION OF MOLECULAR SPECIES IN GROUP III-V COMPOUNDS

1962 ◽  
Vol 66 (3) ◽  
pp. 575-576 ◽  
Author(s):  
A. J. Ahearn ◽  
C. D. Thurmond
2018 ◽  
Vol 14 (2) ◽  
pp. 96-107
Author(s):  
César Palacios A. ◽  
Noemi Guerra ◽  
Marco Guevara ◽  
María José López

The performance of solar cells has improved quickly in recent years, the latest research focuses on thin cells, multijunction cells, solar cells of the group III-V compounds, Tandem cells, etc. In the present work, numerical simulations are developed, using SENTAURUS TCAD as a tool, in order to obtain a solar cell model based on Galium Arsenide (GaAs). This solar cell corresponds to the so-called "Thin Films" due to the fact that can make layers thinner than we would have if we work with conventional semiconductors, such as; Silicon or Germanium; thus opening the possibility of placing the cell as a top layer within a tandem solar cell configuration with compounds of group III-V. That is why two types of simulations are performed with respect to the contact of the rear contact; one corresponds to the cell with a lower contact equal to the length of the cell and the other with a small contact of 5 μm. In addition, the cell undergoes an optimization process by modifying the geometry and doping of the layers that comprise it, in order to improve its performance. To achieve this objective, the initial conditions and the appropriate simulation parameters must be determined, which have been selected and corroborated with the literature, allowing us to arrive at coherent results and optimal models of solar cell design through numerical simulations.


1972 ◽  
Vol 26 (3) ◽  
pp. 364-369 ◽  
Author(s):  
M. S. Wang

Methods for determination of trace and ultratrace impurities in group III–V compounds by emission spectroscopy have been investigated. Cleaning of organic and inorganic surface contaminants must be carefully carried out so that ultratrace determination is possible. The method takes advantage of preferential volatilization of group III-V compounds in a dc arc. Sequential exposure is used to improve signal-to-noise ratio. Concentrating the impurities in the electrode by arcing off some of the arsenic in gallium arsenide improves detection limits of relatively nonvolatile elements. The analytical results agree well with other techniques. Electrical properties of compounds also correlate well with the data. The coefficients of variation range from 20 to 40%.


Author(s):  
K.K. SEKHRI ◽  
C.S. ALEXANDER ◽  
H.T. NAGASAWA

C57BL male mice (Jackson Lab., Bar Harbor, Maine) weighing about 18 gms were randomly divided into three groups: group I was fed sweetened liquid alcohol diet (modified Schenkl) in which 36% of the calories were derived from alcohol; group II was maintained on a similar diet but alcohol was isocalorically substituted by sucrose; group III was fed regular mouse chow ad lib for five months. Liver and heart tissues were fixed in 2.5% cacodylate buffered glutaraldehyde, post-fixed in 2% osmium tetroxide and embedded in Epon-araldite.


Author(s):  
Anton Bózner ◽  
Mikuláš Gažo ◽  
Jozef Dostál

It is anticipated that Japanese quail /Coturnix coturnix japonica/ will provide animal proteins in long term space flights. Consequently this species of birds is of research interest of international space program INTERCOSMOS. In the year 1987 we reported on an experiment /2/ in which the effect of chronic acceleration of 2 G hypergravitation, the hypodynamy and the simultaneous effect of chronic acceleration and the location in the centre of the turntable of the centrifuge on the protein fractions in skeletal muscles was studied. The ultrastructure of the heart muscle was now in this experiments examined as well.Japanese quail cockerels, aged 48 days were exposed to 2 G hypergravitation /group IV/ in a 6,4 m diameter centrifuge, to hypodynamy /group III/ and their combination /group V/, respectively for 6 days / Fig.1/. The hypodynamy in group III was achieved by suspending the birds in jackets without contact the floor. The group II was located in the centre ofthe turntable of the centrifuge. The control group I. was kept under normal conditions. The quantitative ultrastructure of myocard was evaluated by the methods of Weibel/3/ - this enables to determine the number, relative size and volume of mitochondria volume of single mitochondria, defficiency of mitochondrial cristae and volume of myofibrils.


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