A quick method to determine the capacitance characteristics of thin layer X5R multilayer capacitors

2012 ◽  
Vol 32 (1) ◽  
pp. 167-173 ◽  
Author(s):  
R. Mikkenie ◽  
O. Steigelmann ◽  
W.A. Groen ◽  
J.E. ten Elshof
2015 ◽  
Vol 799-800 ◽  
pp. 407-412 ◽  
Author(s):  
Mohamed O. Helmy ◽  
Ahmed M. Fath El-Bab ◽  
Hassan El-Hofy

The accuracy and clogging of microchannels are important for assessing the quality of lab on chip (L-O-C) devices. The clogging affects the fluid mixing efficiency and influences the bonding of substrate. In this paper, inexpensive and quick method for microchannel fabrication in polymethyl methacrylate (PMMA) while reducing the thermal damage is introduced. Accordingly, the substrate was covered with a thin layer of water during CO2laser ablation. The effect of water cooling on the clogging formation, heat affected zone and the microchannel geometry in terms of depth and width is investigated. Clogging formation mechanism in the intersection of Y-channel is studied to improve its quality for microfluidics applications. During the experimental work, the CO2laser power was varied from 2.4 to 6 W at scanning speed from 5 to 12.5 mm/s. The results showed that covering the PMMA substrate with a thin layer of water prevented clogging formation and reduced the heat affected zone.


Author(s):  
Lorna S F Hsu ◽  
J I Sharrard ◽  
C Love ◽  
T C Marrs

We report a quick method for the detection of cocaine and its major metabolites by thin-layer chromatography with confirmation by gas-liquid chromatography. Because it is possible to use the same chloroform-isopropanol extracts of urine in both procedures, the method is convenient for screening large numbers of urine samples.


1971 ◽  
Vol 17 (1) ◽  
pp. 49-50 ◽  
Author(s):  
Theodore N Hackett ◽  
Patrick F Bray

Abstract Increased urinary excretion of o-hydroxyphenylacetic acid is a generally accepted sign of phenylketonuria. Most reported methods for measuring this metabolite require 24 h. We describe a procedure for its separation in 90 min by thin-layer chromatography. Thus, essential dietary therapy is speeded.


Author(s):  
William J. Baxter

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.


Crisis ◽  
2010 ◽  
Vol 31 (2) ◽  
pp. 109-112 ◽  
Author(s):  
Hui Chen ◽  
Brian L. Mishara ◽  
Xiao Xian Liu

Background: In China, where follow-up with hospitalized attempters is generally lacking, there is a great need for inexpensive and effective means of maintaining contact and decreasing recidivism. Aims: Our objective was to test whether mobile telephone message contacts after discharge would be feasible and acceptable to suicide attempters in China. Methods: Fifteen participants were recruited from suicide attempters seen in the Emergency Department in Wuhan, China, to participate in a pilot study to receive mobile telephone messages after discharge. All participants have access to a mobile telephone, and there is no charge for the user to receive text messages. Results: Most participants (12) considered the text message contacts an acceptable and useful form of help and would like to continue to receive them for a longer period of time. Conclusions: This suggests that, as a low-cost and quick method of intervention in areas where more intensive follow-up is not practical or available, telephone messages contacts are accessible, feasible, and acceptable to suicide attempters. We hope that this will inspire future research on regular and long-term message interventions to prevent recidivism in suicide attempters.


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