Intermediate Resonance Absorption at Low Energies

Experimental point-projection shadow microscope (PPM) images of uncoated, unstained purple membrane (PM, bacteriorhodopsin, a membrane protein from Halobacterium holobium) were obtained recently using 100 volt electrons. The membrane thickness is about 5 nm and the hexagonal unit cell dimension 6 nm. The images show contrast around the edges of small holes, as shown in figure 1. The interior of the film is opaque. Since the inelastic mean free path for 100V electrons in carbon (about 6 Å) is much less than the sample thickness, the question arises that how much, if any, transmission of elastically scattered electrons occurs. A large inelastic contribution is also expected, attenuated by the reduced detection efficiency of the channel plate at low energies. Quantitative experiments using an energy-loss spectrometer are planned. Recently Shedd has shown that at about 100V contrast in PPM images of thin gold films can be explained as Fresnel interference effects between different pinholes in the film, separated by less than the coherence width.

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Electrical Damage Due to Low Energy Plasma Processing of GaAs Structures

MRS Proceedings ◽

10.1557/proc-223-209 ◽

1991 ◽

Vol 223 ◽

Author(s):

Hans P. Zappe ◽

Gudrun Kaufel

Keyword(s):

Chemical Processes ◽

Low Energy ◽

Electrical Behavior ◽

Rapid Thermal Anneal ◽

High Temperature Anneal ◽

Significant Damage ◽

Low Energies ◽

Long Time ◽

Physical Plasma

ABSTRACTThe effect of numerous plasma reative ion etch and physical milling processes on the electrical behavior of GaAs bulk substrates has been investigated by means of electric microwave absorption. It was seen that plasma treatments at quite low energies may significantly affect the electrical quality of the etched semiconductor. Predominantly physical plasma etchants (Ar) were seen to create significant damage at very low energies. Chemical processes (involving Cl or F), while somewhat less pernicious, also gave rise to electrical substrate damage, the effect greater for hydrogenic ambients. Whereas rapid thermal anneal treatments tend to worsen the electrical integrity, some substrates respond positively to long-time high temperature anneal steps.

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EXPERIMENTAL STUDY OF REACTION OF ETHANOL WITH OXYGEN BEHIND SHOCK WAVES USING ATOMIC RESONANCE ABSORPTION SPECTROSCOPY METHOD

NONEQUILIBRIUM PROCESSES. Vol. 2. Fundamentals of combustion ◽

10.30826/nepcap2018-2-35 ◽

2020 ◽

Author(s):

N. S. Bystrov ◽

◽

A. V. Emelianov ◽

A. V. Eremin ◽

P. I. Yatsenko ◽

...

Keyword(s):

Experimental Study ◽

Shock Waves ◽

Absorption Spectroscopy ◽

Vacuum Ultraviolet ◽

Resonance Absorption ◽

Atomic Resonance ◽

Quantitative Measurements ◽

Series Of Experiments ◽

Kinetics Of Reaction ◽

Oxygen Atoms

The kinetics of reaction of C2H5OH with N2O behind shock waves is studied. The quantitative measurements of the time profiles of concentration of O atoms were carried out by the method of atomic resonance absorption spectroscopy (ARAS) using resonance vacuum-ultraviolet line of O-atom at 130.5 nm. For the calibration of absorption intensity of oxygen atoms depending on its concentration, the special series of experiments in the mixture containing different amounts of N2O in Ar was carried out at T = 2100 ± 50 K when molecule of N2O is completely dissociated. An experimental study of the appearance and consumption of oxygen atoms during the reaction of ethanol with oxygen in mixture 10 ppm N2O + (10 ... 0.1) ppm C2H5OH + Ar at temperatures of 16002300 K and pressures of 200-300 kPa have been carried out. A kinetic analysis of obtained data was performed using the Chemkin package.

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Detection of Cefazolin Based on the Plasma Resonance Absorption of Gold Nanoparticles

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1095.2012.00231 ◽

2012 ◽

Vol 29 (4) ◽

pp. 455

Author(s):

Jingyun LI ◽

Yi WANG ◽

Jiali XU ◽

Yuanfang LI

Keyword(s):

Gold Nanoparticles ◽

Resonance Absorption ◽

Plasma Resonance

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