A New Method for Quantitatively Evaluating Defects of the Green Body in Injection Moulding Based on X-Ray Digital Radiography

2013 ◽  
Vol 652-654 ◽  
pp. 2093-2098
Author(s):  
Wei Fang ◽  
Xin Bo He ◽  
Rui Jie Zhang ◽  
Xuan Hui Qu
Keyword(s):  
Density Distribution ◽  
Quantitative Evaluation ◽  
Digital Radiography ◽  
Injection Moulding ◽  
Particle Density ◽  
Dimensional Accuracy ◽  
Inference System ◽  
X Ray ◽  
Powder Content ◽  
Gray Values

Attempts have been made to develop a gray value-matching detection method for quantitative evaluation of defects and density of green parts in metal injection moulding, based on the analysis of X-ray digital radiography images. The results show that the range of gray values should be in about 1.4% when the dimensional accuracy is required within 0.3%, and voids are present where fluctuation of the gray value is larger than 10%. The quantitative evaluation of voids, powder content and density distribution through the gray value-matching can respectively predict severity of voids, shrinkage, and deformation in the sintering stage. Furthermore, the ability to detect defects and particle density distribution of this method allows for the development of an inference system to predict the optimal parameters.

scholarly journals Quantitative Evaluation of Unfilled Grout in Tendons of Prestressed Concrete Girder Bridges by Portable 950 keV/3.95 MeV X-ray Sources

2021 ◽  
Vol 11 (12) ◽  
pp. 5525
Author(s):  
Mitsuru Uesaka ◽  
Jian Yang ◽  
Katsuhiro Dobashi ◽  
Joichi Kusano ◽  
Yuki Mitsuya ◽  
...  
Keyword(s):  
Structural Analysis ◽  
Quantitative Evaluation ◽  
Prestressed Concrete ◽  
Quantitative Difference ◽  
Three Dimensional ◽  
Electron Linear Accelerator ◽  
X Ray ◽  
Girder Bridges ◽  
Girder Bridge ◽  
Gray Values

We have developed porTable 950 keV/3.95 MeV X-band (9.3 GHz) electron linear accelerator (LINAC)-based X-ray sources and conducted onsite prestressed concrete (PC) bridge inspection in the last 10 years. A T-shaped PC girder bridge with a thickness of 200–400 mm and a box-shaped PC girder bridge with a thickness of 200–800 mm were tested. X-ray transmission images of flaws such as thinning, fray, and disconnection caused by corrosion of PC wires and unfilled grout were observed. A three-dimensional structural analysis was performed to estimate the reduction in the yield stress of the bridge. In this study, we attempted to evaluate the unfilled grout quantitatively because it is the main flaw that results in water filling and corrosion. In the measured X-ray images, we obtained gray values, which correspond to the X-ray attenuation coefficients of filled/unfilled grouts, PC wires (steel) in a sheath, and concrete. Then, we compared the ratio of the gray values of the filled/unfilled grouts and PC wires to determine the stage of the unfilled grout. We examined this quantitative evaluation using the data obtained from a real T-shaped PC girder bridge and model samples to simulate thick box-shaped PC girder bridges. We obtained a clear quantitative difference in the ratios for unfilled and filled grouts, which coincided with our visual perception. We synthesized the experience and data and proposed a quantitative analysis for evaluating the unfilled grout for subsequent steps such as structural analysis and destructive evaluation by boring surveys.

Evaluation of the Radiopacities of Bulk-fill RestorativesUsing Two Digital Radiography Systems

2015 ◽  
Vol 40 (5) ◽  
pp. E197-E205 ◽  
Author(s):  
E Yasa ◽  
B Yasa ◽  
OS Aglarci ◽  
ET Ertas
Keyword(s):  
Digital Radiography ◽  
Complementary Metal Oxide Semiconductor ◽  
American National Standard Institute ◽  
Oxide Semiconductor ◽  
National Standard ◽  
X Ray ◽  
Cmos Sensor ◽  
Photostimulable Phosphor ◽  
The Mean ◽  
Gray Values

SUMMARY This study investigated the radiopacity values of bulk-fill restoratives by using two digital radiography systems. Nine bulk-fill restoratives and a conventional composite were used in the study. Six disc-shaped specimens were prepared from each of these materials, three each at thicknesses of 1 mm and 2 mm, and tooth slices with these same thicknesses were obtained. As a control, an aluminum step wedge varying in thickness from 0.5 to 10 mm in was used. Three specimens of each of the materials, together with the tooth slice and the aluminum step wedge, were placed over a complementary metal oxide semiconductor (CMOS) sensor and a storage photostimulable phosphor (PPS) plate system and exposed using a dental x-ray unit. The images were analyzed using a software program to measure the mean gray values (MGVs). Five measurements were obtained from each of the restorative materials, the enamel, the dentin, and the stepwedge. The MGVs were converted to the equivalent aluminum thicknesses. Three-way analysis of variance (ANOVA) was used to determine the significance of the differences among the groups. A Tukey test was applied for pairwise comparisons (p<0.05). All composite-based restoratives were found to have greater radiopacities than enamel or dentin. Equia Fil had the lowest radiopacity value. Radiopacity increased as the thicknesses of the restorative material increased. The CMOS system showed significantly higher radiopacity values than the PSP system. In conclusion, all investigated bulk-fill restoratives passed the International Organization for Standardization and American National Standard Institute/American Dental Association requirements for radiopacity values when evaluated with the two digital radiography systems.

A study on α-RuCl3 crystal structure by scanning tunneling microscopy

1989 ◽  
Vol 47 ◽  
pp. 30-31
Author(s):  
H.-J. Cantow ◽  
H. Hillebrecht ◽  
S. Magonov ◽  
H. W. Rotter ◽  
G. Thiele
Keyword(s):  
Crystal Structure ◽  
Density Distribution ◽  
Scanning Tunneling Microscopy ◽  
Electron Density ◽  
Structure Determination ◽  
Electron Density Distribution ◽  
Scanning Tunneling ◽  
Monoclinic Space Group ◽  
Tunneling Microscopy ◽  
X Ray

From X-ray analysis, the conclusions are drawn from averaged molecular informations. Thus, limitations are caused when analyzing systems whose symmetry is reduced due to interatomic interactions. In contrast, scanning tunneling microscopy (STM) directly images atomic scale surface electron density distribution, with a resolution up to fractions of Angstrom units. The crucial point is the correlation between the electron density distribution and the localization of individual atoms, which is reasonable in many cases. Thus, the use of STM images for crystal structure determination may be permitted. We tried to apply RuCl3 - a layered material with semiconductive properties - for such STM studies. From the X-ray analysis it has been assumed that α-form of this compound crystallizes in the monoclinic space group C2/m (AICI3 type). The chlorine atoms form an almost undistorted cubic closed package while Ru occupies 2/3 of the octahedral holes in every second layer building up a plane hexagon net (graphite net). Idealizing the arrangement of the chlorines a hexagonal symmetry would be expected. X-ray structure determination of isotypic compounds e.g. IrBr3 leads only to averaged positions of the metal atoms as there exist extended stacking faults of the metal layers.

X-ray emission and X-ray photoelectron studies of electron density distribution in Cu(II) complexes with 2-imidazoline nitroxides

2006 ◽  
Vol 47 (3) ◽  
pp. 558-562 ◽  
Author(s):  
L. N. Mazalov ◽  
S. V. Trubina ◽  
G. K. Parygina ◽  
I. M. Oglezneva ◽  
E. A. Aseeva ◽  
...  
Keyword(s):  
Density Distribution ◽  
Electron Density ◽  
Electron Density Distribution ◽  
X Ray

MAGNETIC MICROSPECTROSCOPY BY A COMBINATION OF XMCD AND PEEM

2002 ◽  
Vol 09 (02) ◽  
pp. 877-881 ◽  
Author(s):  
S. IMADA ◽  
S. SUGA ◽  
W. KUCH ◽  
J. KIRSCHNER
Keyword(s):  
Circular Dichroism ◽  
Full Advantage ◽  
Quantitative Evaluation ◽  
Magnetic Circular Dichroism ◽  
Magnetic Moments ◽  
Magnetic Domain ◽  
X Ray ◽  
Circular Dichroïsm

The benefits of combining soft X-ray magnetic circular dichroism and photoelectron microscopy are demonstrated by applying this combination (XMCD–PEEM) not only to magnetic domain imaging but also to quantitative evaluation of the distribution of spin and orbital magnetic moments. The latter takes full advantage of the spectroscopic aspect of XMCD–PEEM.

Development of a novel direct X-ray detector using photoinduced discharge (PID) readout for digital radiography

2013 ◽  
Vol 8 (02) ◽  
pp. C02045-C02045
Author(s):  
D Heo ◽  
S Jeon ◽  
J -S Kim ◽  
R K Kim ◽  
B K Cha ◽  
...  
Keyword(s):  
Digital Radiography ◽  
X Ray
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