In X-ray TICT, when X-ray is transmitted in the materal, the phenomenon of energy spectrum hardening takes place, resulting in artifacts. Thus, hardening correction has to be done. In the present paper, the phenomenon of X-ray beam hardening resulting in analyized, and the relation between the X-ray beam sum and the transmission thickness in testing composites workpiece is discussed. According to the Beer law and the characteristics of the interaction between X-ray and the material, and getting the data of X-ray beam sum, the relation equation between the beam sum and transmission thickness is simulated firstly, and testing composites workpiece. Then, the relation and the method of equivalence are carried out between the equivalent transmission thickness and the transmission thickness for X-ray beam sum being corrected for monochromatic ray beam. Finally, the attenuation coefficient beam hardening simulated value for X-ray equivalent monochromatic is reasoned out in testing composites workpiece. Then, the attenuation coefficient simulated value that has been corrected is used for product back-projection reconstruction. Thus, the effect caused by X-ray beam hardening is wipped off effectively in testing composites workpiece.
Download full-text PDF |
Source |
---|
Appl Microbiol Biotechnol
January 2025
Process Synthesis and Process Dynamics, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany.
The production of biodegradable and biobased polymers is one way to overcome the present plastic pollution while using cheap and abundant feedstocks. Polyhydroxyalkanoates are a promising class of biopolymers that can be produced by various microorganisms. Within the production process, batch-to-batch variation occurs due to changing feedstock composition when using waste streams, slightly different starting conditions, or biological variance of the microorganisms.
View Article and Find Full Text PDFJ Nat Prod
January 2025
Department of Chemical and Biological engineering, School of Engineering and Technology, National University of Mongolia, Ulaanbaatar 14201, Mongolia.
A chemical examination of a root extract of led to the isolation and identification of 23 compounds, including oxazole-type alkaloids and isoflavonoid derivatives. Notably, three oxazole-type alkaloids (, , and ) and two isoflavonoid derivatives ( and ) were obtained from a natural source for the first time. In addition, derived 2,5-diphenyloxazoles and their derivatives were synthesized.
View Article and Find Full Text PDFAm J Health Promot
January 2025
Institute for Behavioral and Community Health, San Diego State University, San Diego, CA, USA.
Purpose: Social support, particularly from family, is crucial for physical activity (PA) among youth. This study examined the association between father support and moderate-to-vigorous physical activity (MVPA) in Latina pre-teens and explored the moderating role of body mass index (BMI).
Design: Cross-sectional analysis.
J Esthet Restor Dent
January 2025
Operative Department, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.
Objective: To investigate the effect of cervical margin relocation with four different injectable restorative materials on the fracture resistance of molars receiving mesio-occluso-distal CAD/CAM nanoceramic onlay restorations.
Materials And Methods: One hundred and five sound mandibular molars received a standardized mesio-occluso-distal onlay preparation, with cervical margins located 2 mm apical to the cemento-enamel junction. The molars were randomly allocated into five groups (n = 21) according to the cervical relocating materials used: Group I had no cervical margin relocation; Group II used a highly viscous glass ionomer; Group III used a highly-filled injectable resin composite; Group IV used a resin-modified glass ionomer; and Group V used a bioactive ionic resin.
J Esthet Restor Dent
January 2025
Department of Restorative Dentistry, Faculty of Dentistry, Kırıkkale University, Kırıkkale, Türkiye.
Objective: This in vitro study aims to evaluate the effect of placing polyethylene fibers used in large Class II MOD (mesio-occlusion-distal) cavities into different flowable resin composites and in different positions on the fracture resistance of the restoration.
Materials And Methods: Ninety healthy human molars were used in the study. No treatment was performed on 10 of these teeth and they were used as the control group.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!