The present work, aims to inspect by ultrasonic method numbers of imported steel
billets, which cause stopping and breaking in the production – lines.
The inspection was done by using ultrasonic detector,(echo – pulse method), a
straight – beam pr
obe was used as a transducer and receiver, at the same time.
The results of inspection showed the possibility of accurate defect determination in
steel billets, and also showed a good agreement between the experimental results and the
number of stopping and breaking in production in factory, and also the necessity to use that
inspection method in the imported billets which cause the continuous breaking in the
production – lines.
The use of Nickel-Titanium rotary instruments have been increasing in the last two
decades. But the probability of fracture is still the most important hindrance that confuse
the practitioners. And many clinicians claim that the removal process is
very difficult and
often irretrievable. When compared with stainless steel instruments, hence this study aims
to compare between the two types effect of endodontic instruments on the success of
microsonic technique in removing or bypassing it, and the degree of difficulty.
Aim of the study: To study the effectiveness of using dental operating microscope
and ultrasonics with Hedstrom files in removing gutta-percha and sealer from root canals.
Materials and Methods: Twenty single straight rooted, extracted human mandib
ular
premolars were prepared, filled with gutta-percha and sealer (Zinc oxide with eugenol).
Specimens were then divided into two groups (N1=N2=10), and root filling material was
removed using H-files with Eucalyptol (group 1); H-files with Eucalyptol, followed by
using microscope with ultrasonic tip (group 2). After retreatment, the efficacy of each
technique was examined at 8× magnification with a stereomicroscope then the images were
analyzed using Auto-CAD 2010 according to Hulsmann and Stotz scale.
Data were statistically analyzed using Mann–Whitney U-tests.
Sweeteners are used as alternatives of Sugar because of their slow
absorption and incomplete metabolism in human body, which are positively
destinies in setting free small amount of calorie.
This research presents the influence of ultrasonic on th
e sorbitol synthesis,
starting from Glucose by implementing hydrogenation using Lithium
Aluminum Hydride. The result we have reached by using the ultrasonic as
compared with mechanical mixing or other method have lead us to two
conclusions:
The first was that we have obtained almost the same quantity of the sorbitol.
The second was that by using ultrasonic, micelles of colloid Aluminum
hydroxide were accumulated. This accumulation resulted in an easy separation
by purification, which eventually lead to a super pure sorbitol solution.
We hope that these results will be useful for the Crystallography science.
