Mathematical Behavior of Optical Density of γ-Ray Radiography Images of Steel Pipes

2019 ◽  
Vol 55 (12) ◽  
pp. 967-974 ◽  
Author(s):  
Mohammad Taghan Sasanpour ◽  
Ali Taheri ◽  
Amir Movafeghi ◽  
Behrouz Rokrok
1965 ◽  
Vol 24 (1) ◽  
pp. 31-37 ◽  
Author(s):  
Jacques Vincent ◽  
Stanislas Haumont ◽  
Joseph Roels

Longitudinal sections of human cortical bone were submitted to thermal neutrons. γ-ray spectra were recorded repeatedly during 15 days following irradiation. They showed that Na24 is predominant as early as 3 hours after activation and that all the γ-emitters have decayed on the 15th day. When the γ-rays have disappeared, ß-rays are still produced by the sections. It was proved by the absorption curve in aluminium that all these ß-rays are issued from the P32 induced in the sections by activation of P31. Therefore autoradiograms registered 15 days after activation reveal the distribution of P32 in the sections. γ-ray spectra and ß-ray absorption curves of neutron activated sections of ivory demonstrated a mineral composition similar to that of bone. Autoradiograms of ivory sections activated for various times were used to establish the relation between the optical density of the autoradiograms and the radioactivity in P32. When the bone autoradiograms are compared with the ivory standards of known radioactivity, the optical densities of single osteons (Haversian systems), can be related to their phosphorus contents. Autoradiograms and microradiograms of the same sections were examined side by side. The least calcified osteons, that contain 80 per cent of the calcium of the fully calcified osteons, also contain about 80 per cent of the phosphorus of the fully mineralized osteons. It is concluded that the Ca:P ratio remains constant while mineralization of bone tissue is being completed.


Author(s):  
James R. Kremer ◽  
Paul S. Furcinitti ◽  
Eileen O’Toole ◽  
J. Richard McIntosh

Characteristics of electron microscope film emulsions, such as the speed, the modulation transfer function, and the exposure dependence of the noise power spectrum, have been studied for electron energies (80-100keV) used in conventional transmission microscopy. However, limited information is available for electron energies in the intermediate to high voltage range, 300-1000keV. Furthermore, emulsion characteristics, such as optical density versus exposure, for new or improved emulsions are usually only quoted by film manufacturers for 80keV electrons. The need for further film emulsion studies at higher voltages becomes apparent when searching for a film to record low dose images of radiation sensitive biological specimens in the frozen hydrated state. Here, we report the optical density, speed and relative resolution of a few of the more popular electron microscope films after exposure to 1MeV electrons.Three electron microscope films, Kodak S0-163, Kodak 4489, and Agfa Scientia 23D56 were tested with a JEOLJEM-1000 electron microscope operating at an accelerating voltage of 1000keV.


1991 ◽  
Vol 16 (4) ◽  
pp. 443-457
Author(s):  
R. Lehoucq ◽  
Ph. Durouchouxa
Keyword(s):  
Sn 1987A ◽  

1973 ◽  
Vol 29 (03) ◽  
pp. 536-546 ◽  
Author(s):  
M Lacombe ◽  
J Soria ◽  
C Soria ◽  
G d’Angelo ◽  
R Lavallee ◽  
...  

SummaryA new case of congenital dysfibrinogenemia characterized by a prolonged thrombin clotting time and a low optical density of the polymerization curve has been discovered in Montreal. The functional defect is due to an abnormal aggregation of fibrin monomers.The characteristics of this abnormal fibrinogen are serum gélification (Paracoagulation) at 37°, 22° and 4° C, a normal immuno-electrophoretic and electrofocusing pattern, a slight increase in the mobility in the α (A) chain by electrophoresis of the dissociated chains in polyacrylamide gel. However, no abnormality was found in the α (A) chain of the disulphide knot.


1978 ◽  
Vol 39 (02) ◽  
pp. 455-465 ◽  
Author(s):  
Yvonne Stirling ◽  
D J Howarth ◽  
Marguerite Vickers ◽  
W R S North ◽  
T W Meade

SummaryTwo automated methods for two-stage factor VIII assays have been compared with one another, and evaluated in practice. The Depex method records the clotting time when an electric circuit is completed by the formation of a fibrin thread across a hook-type electrode; the Electra method is based on an optical density technique of clot detection. The two methods gave comparable results for measured levels of factor VIII when haemophilic or “normal” plasmas were assayed. Results from the two methods in practice also suggest that both are valid at low and “normal” factor VIII levels. The Electra method is also probably suitable for assays of concentrates; however, the Depex method appears to give falsely high values in these circumstances, and experimental findings suggest that the reason may be that increased viscosity due to the high fibrinogen levels in factor VIII concentrates causes premature closure of the circuit between the two ends of the Depex electrode. The main advantage of the Depex method is that, provided 3 or 4 machines are available, a given number of assays can be completed more quickly than on Electra. The main advantages of Electra are that it is probably subject to less laboratory error than Depex, and that it is suitable for assaying concentrates as well as haemophilic and “normal” plasmas.


1977 ◽  
Vol 37 (02) ◽  
pp. 329-338 ◽  
Author(s):  
Tadahiro Sano ◽  
Takeshi Motomiya ◽  
Hiroh Yamazaki ◽  
Takio Shimamoto

SummaryA new method for assessment of platelet sensitivity to ADP-aggregation was devised. Its reproducibility and the correlations between the values obtained by this method, the optical density (O. D.) method, and the screen filtration pressure (SFP) method were assessed. In summary, this method may be said to have three main points:1. It can be performed without centrifugation, avoiding mechanical stress to platelets, using only 0.8 ml. of blood and inexpensive equipment.2. It may reflect different aspects of platelet function from the O. D. method and the SFP method, despite the positive significant correlations between the values obtained by these three methods.3. It was proved to be highly reproducible and is thought to be useful clinically.By using this method, the effect of sustained isometric exercise by handgripping on platelet aggregability was assessed in coronary sclerotic and cerebral arteriosclerotic patients on placebo and EG-626, a newly synthesized cyclic AMP phosphodiesterase inhibitor. On placebo, an enhancement of platelet sensitivity was observed after isometric exercise in coronary and cerebral arteriosclerotic patients but not in healthy control subjects. The enhancement was prevented by pretreatment of EG-626, administered orally 1.5 hours prior to exercise.


Author(s):  
N. G. Zinov’eva

Structure of the Russian export and import of steel industry products presented by results of 9 months of 2019 operation. It was shown, that the total share of pig iron, ferroalloys and semi-products (40.3%) in the ferrous metals export from Russia is practically the same as the share of rolled products and steel pipes (39.4%), whereas the shares in the import structure were 7.7 and 75% accordingly. The share the far abroad countries in the Russian export and import of finished steel products (in natural terms) accounted for 80.6 and 28.7% accordingly, while the share of CIS countries – 19.4 and 71.3% accordingly. For 9 months of 2019 the Russian export of semi-products declined by 10.9% comparing with the analogue period of 2018 and accounted for 10.9 m tons. 54.6% of the total export shipping of semi-products were directed to Mexico, Turkey, Egypt and Taiwan. Within the nearest years the Russian export of semi-products and billets, in particular, will be effected by the further development of the semi-products production in in the countries of Middle East, Turkey, Vietnam and India. The domestic market remained to be more attractive for many Russian companies. For the 9 months of 2019, export of long and flat products accounted for 3 and 5.7 m tons accordingly, declining comparing with the analogue period of the previous year by 11 and 15.6% accordingly. Import of long and flat products decreased by 12 and 0.5%, accounting for 1.0 and 2.9 m tons accordingly. By the results of 9 months of 2019, import declined and export shipping of coated sheet increased. Taking into account the expansion of steel grades assortment by Russian plants, increase of capacities for production of sheet with different coatings, this tendency is likely to remain.


2020 ◽  
Vol 3 (2) ◽  
pp. 781-790
Author(s):  
M. Rizwan Akram ◽  
Ali Yesilyurt ◽  
A.Can. Zulfikar ◽  
F. Göktepe

Research on buried gas pipelines (BGPs) has taken an important consideration due to their failures in recent earthquakes. In permanent ground deformation (PGD) hazards, seismic faults are considered as one of the major causes of BGPs failure due to accumulation of impermissible tensile strains. In current research, four steel pipes such as X-42, X-52, X-60, and X-70 grades crossing through strike-slip, normal and reverse seismic faults have been investigated. Firstly, failure of BGPs due to change in soil-pipe parameters have been analyzed. Later, effects of seismic fault parameters such as change in dip angle and angle between pipe and fault plane are evaluated. Additionally, effects due to changing pipe class levels are also examined. The results of current study reveal that BGPs can resist until earthquake moment magnitude of 7.0 but fails above this limit under the assumed geotechnical properties of current study. In addition, strike-slip fault can trigger early damage in BGPs than normal and reverse faults. In the last stage, an early warning system is proposed based on the current procedure. 


2002 ◽  
Vol 722 ◽  
Author(s):  
Ram W. Sabnis ◽  
Mary J. Spencer ◽  
Douglas J. Guerrero

AbstractNovel organic, polymeric materials and processes of depositing thin films on electronics substrates by chemical vapor deposition (CVD) have been developed and the lithographic behavior of photoresist coated over these CVD films at deep ultraviolet (DUV) wavelength has been evaluated. The specific monomers synthesized for DUV applications include [2.2](1,4)- naphthalenophane, [2.2](9,10)-anthracenophane and their derivatives which showed remarkable film uniformity on flat wafers and conformality over structured topography wafers, upon polymerization by CVD. The chemical, physical and optical properties of the deposited films have been characterized by measuring parameters such as thickness uniformity, solubility, conformality, adhesion to semiconductor substrates, ultraviolet-visible spectra, optical density, optical constants, defectivity, and resist compatibility. Scanning electron microscope (SEM) photos of cross-sectioned patterned wafers showed verticle profiles with no footing, standing waves or undercut. Resist profiles down to 0.10 νm dense lines and 0.09 νm isolated lines were achieved in initial tests. CVD coatings generated 96-100% conformal films, which is a substantial improvement over commercial spin-on polymeric systems. The light absorbing layers have high optical density at 248 nm and are therefore capable materials for DUV lithography applications. CVD is a potentially useful technology to extend lithography for sub-0.15 νm devices. These films have potential applications in microelectronics, optoelectronics and photonics.


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