<title>Real-time in-situ determination of free Cu(II) at picomolar levels in sea water using a fluorescence lifetime-based fiber optic biosensor</title>

A method for real-time determination of the percent cure of epoxies via in situ fiber-optic Raman spectroscopy has been developed. This method utilizes a probe design developed for real-time monitoring of polymer curing and multivariate analysis to interpret the data and determine percent cure. This method was demonstrated to be reliable to ±0.54% of cure in laboratory samples over a 50–99% cure range. A preliminary study measuring cure percentage in an industrial, glass-reinforced composite has been shown to be reliable to ±0.82% in the 40–90% cure range.

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Real-Time Analysis Of In-Situ Spectroscopic Ellipsometric Data During Mbe Growth Of III-V Semiconductors

MRS Proceedings ◽

10.1557/proc-222-75 ◽

1991 ◽

Vol 222 ◽

Cited By ~ 10

Author(s):

B. Johs ◽

J. L. Edwards ◽

K. T. Shiralagi ◽

R. Droopad ◽

K. Y. Choi ◽

...

Keyword(s):

Real Time ◽

Optical Constants ◽

Growth Parameters ◽

Ex Situ ◽

Time Analysis ◽

Mbe Growth ◽

In Situ Data ◽

Real Time Analysis

ABSTRACTA modular spectroscopic ellipsometer, capable of both in-situ and ex-situ operation, has been used to measure important growth parameters of GaAs/AIGaAs structures. The ex-situ measurements provided layer thicknesses and compositions of the grown structures. In-situ ellipsometric measurements allowed the determination of growth rates, layer thicknesses, and high temperature optical constants. By performing a regression analysis of the in-situ data in real-time, the thickness and composition of an AIGaAs layer were extracted during the MBE growth of the structure.

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Determination of 137Cs in Sea Water Samples Using Gamma Spectrometry

HNPS Proceedings ◽

10.12681/hnps.2975 ◽

2020 ◽

Vol 13 ◽

pp. 247

Author(s):

N. Evaggeliou ◽

Ch. Lykomitrou ◽

A. Zafiropoulou

Keyword(s):

Gamma Spectrometry ◽

Comparative Evaluation ◽

Sea Water ◽

Germanium Detector ◽

Advantages And Disadvantages ◽

High Purity Germanium ◽

Co Precipitation ◽

Radioanalytical Procedures

In the present study a comparative evaluation of two methods for 137Cs determination (pretreatment for gamma spectrometry) is attempted. One of them is the conventional AMP (ammonium molybdophosphate, (ΝΗ4)3Ρ(Μo3O10)4) method (radiochemical treatment based on coprecipitation) and the other one is a method based on pre-concentration of cesium in situ by using the Mark III Centrifugal Pump. The pump, which is described analytically in the study, is composed of a motor (pump), four cartridge housings (containing the scavengers), a flow meter and a pressure tube (containing the battery pack and the timer board). For justification, this method is compared with the AMP co-precipitation one. Following up the radioanalytical procedures, the gamma spectrometry system (relative efficiency of high purity germanium detector 90%) is also demonstrated, as conformed to mea suring obtained parameters. Finally, the advantages and disadvantages of these two methods are recorded and the application of each one is suggested.

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