Quantitative Use of Film Density Variations for Thickness Variation Determination by Polychromatic X-Radiography

1995 ◽  
Vol 6 (1) ◽  
pp. 57-68
Author(s):  
Jørgen Rheinlander
Author(s):  
G. Botton ◽  
G. L’Espérance ◽  
M.D. Ball ◽  
C.E. Gallerneault

The recently developed parallel electron energy loss spectrometers (PEELS) have led to a significant reduction in spectrum acquisition time making EELS more useful in many applications in material science. Dwell times as short as 50 msec per spectrum with a PEELS coupled to a scanning transmission electron microscope (STEM), can make quantitative EEL images accessible. These images would present distribution of elements with the high spatial resolution inherent to EELS. The aim of this paper is to briefly investigate the effect of acquisition time per pixel on the signal to noise ratio (SNR), the effect of thickness variation and crystallography and finally the energy stability of spectra when acquired in the scanning mode during long periods of time.The configuration of the imaging system is the following: a Gatan PEELS is coupled to a CM30 (TEM/STEM) electron microscope, the control of the spectrometer and microscope is performed through a LINK AN10-85S MCA which is interfaced to a IBM RT 125 (running under AIX) via a DR11W line.


Author(s):  
Suresh Kulkarni ◽  
Ranjit P. ◽  
Nikunj Patel ◽  
Someshwara B. ◽  
Ramesh B. ◽  
...  

The present investigation deals with the formulation of fast disintegrating tablets of Meloxicam that disintegrate in the oral cavity upon contact with saliva and there by improve therapeutic efficacy. Meloxicam is a newer selective COX-1 inhibitor. The tablets were prepared by wet granulation procedure. The influence of superdisintegrants, crosspovidone, croscaremellose sodium on disintegration time, wetting time and water absorption ratio were studied. Tablets were evaluated for weight and thickness variation, disintegration time, drug content, in vitro dissolution, wetting time and water absorption ratio. The in vitro disintegration time of the best fast disintegrating tablets was found to be 18 sec. Tablets containing crospovidone exhibit quick disintegration time than tablets containing croscaremellose sodium. The fast disintegrating tablets of Meloxicam with shorter disintegration time, acceptable taste and sufficient hardness could be prepared using crospovidone and other excipients at optimum concentration.


2020 ◽  
pp. 38-45
Author(s):  
В.В. Павлюченко ◽  
Е.С. Дорошевич

Based on the developed methods of hysteresis interference, the calculated dependences U(x) of the electric voltage taken from the magnetic field transducer on the x coordinate were obtained. A magnetic carrier with an arctangent characteristic was exposed to a series of bipolar pulses of the magnetic field of a linear inductor of one, two, three, four, five and fifteen pulses. An algorithm is presented for the sequence of changes in the magnitude of the total strength of the magnetic field pulses on the surface of an aluminum plate, which provides the same amplitude of hysteresis oscillations of the electric voltage and makes it possible to obtain a linear difference dependence U(x) for wedge-shaped and flat aluminum samples. The results obtained make it possible to increase the accuracy and efficiency of control of the thickness of the object and its thickness variation in the given directions, as well as the defects of the object.


1988 ◽  
Vol 150 (5) ◽  
pp. 1200-1201
Author(s):  
P Aliabadi
Keyword(s):  

Author(s):  
Ritesh Ray Chaudhuri ◽  
William Simpson ◽  
Daniel Fedor ◽  
Prabhakar Bharatan ◽  
Joseph Thompson ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Azza Ahmed ◽  
Amani Baldo ◽  
A. Sulieman ◽  
Hind Mirghani ◽  
Fouad A. Abolaban ◽  
...  

AbstractThis work aimed to investigate the effect of different shim techniques, voxel sizes, and repetition time (TR) on using theT2 and T2* sequences to determine their optimum settings to investigate the quantification of iron in transfused dependent sickle cell patients. The effect of each of these parameters was investigated on phantoms of different Gadolinium (Gd) concentrations, on 10 volunteers and 25 patients using a1 5T MRI Philips scanner. No significant difference between the three shim techniques was noticed in either T2 or T2* sequence measurements. Pixel sizes of 1 × 1 and 2 × 2 mm provided optimum results for T2 measurements. At 1 × 1 mm pixel size the T2* measurements experienced less error in measurements than the size of 2.5 × 2.5 mm used in the literature. Even though the slice thickness variation did not provide any changes in T2 measurements, the 12 mm provided optimum T2* measurements. TR variation did not yield significant changes on either T2 or T2* measurements. These results indicate that both T2 and T2* sequences can be further improved by providing more reliable measurements and reducing acquisition time.


Author(s):  
Kai Xiong Cheong ◽  
Alvin Wei Jun Teo ◽  
Chui Ming Gemmy Cheung ◽  
Issac Horng Khit Too ◽  
Usha Chakravarthy ◽  
...  

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