Application Of Ultrasonic Treatment Research Articles

Сравнительная характеристика микрофлоры корневого дентина при применении различных вариантов медикаментозной обработки корневых каналов зубов

Application of ultrasonic treatment combined with conventional methods of endodontic treatment contributes to reduce the cases of relapses and the time of treatment, and causes the highest economic effect. The proposed method allows to successfully treating chronic granulating periodontitis and to save the need for prosthetics abutment teeth. The purpose of this study is to increase the effectiveness of treatment of granulating periodontitis by optimizing antiseptic treatment of root canals by means of ultrasound. In a series of studies the material of the examination and treatment of patients in the therapeutic department «Lipetsk municipal dental polyclinic №2» was examined. The basis for receiving scientific data – contingent of 127 patients from 26 to 51 years with granulating form of chronic periodontitis, of these were 83 women and 44 men. Depending on the tactics of the treatment the patients were divided into two groups: the 1st group – 43 patients who were treated by the traditional method of treatment of periodontitis; the 2nd group – 84 persons were treated by means of ultrasound. Clinical examination of patients included visual diagnostics, sensing, thermometry, percussion, determination of conductivity of the tooth pulp, radiovisiographic and x-ray study. It is established, that after use of a 3% solution of sodium hypochlorite the changes are observed not qualitative composition of the microflora, but quantitative. The methods of ultrasonic treatment of chronic granulating periodontitis are developed. The ultrasound effect on the microflora of each root channel is conducted during 30 seconds with the frequency of 30 kHz. The structure of the dentin of the root canal with the help of scanning electronic microscopy, before and after the influence of ultrasound is studied and described. After exposure to 3% of sodium hypochlorite, activated by ultrasound, on the wall of the root canal by granulating periodontitis the growth of microorganisms didn’t revealed in 94,8% of cases.

Application of Ultrasonic Treatment on Collecting Recombinant Protein from Yeast

An appropriate ultrasonication of collecting foreign recombinant protein (human-adiponectin) from yeast was established. Regarded the bioactivity of foreign recombinant protein tested by Western Blotting analysis as parameter, a L9(33) orthogonal array design based on a series of single-factor experiments was employed to optimize conditions for ultrasonic disruption. The results showed that the ultrasonic power of 450 W, duration time on 25 min and operation interval (work time: intermittent time) of 10:10 (s/s) were optimal process with the highest protein bioactivity, and meanwhile, the cell breaking rate was (67.8±2.1) %.

Application of Ultrasonic Treatment on the Stripping of Cellulose Sponge

Cellulose sponge has the characteristic of porous and spongy. It’s difficult to strip in conventional processing. This paper describes a process using ultrasonic aided in solution of thiourea dioxide and sodium hydroxide. The cellulose sponge can be faster and better handled in this process. It will have a better stripping effect. And the optimization parameter of ultrasonic process is described for: thiourea dioxide 30 g/l, sodium hydroxide 40 g/l, the time of 10 min, the temperature of 70 °C. Under the condition of this operation, cellulose sponge stripping rate was 98.8%, the breaking strength loss rate was 27.6%.

Decrosslinking of crosslinked high‐density polyethylene via ultrasonically aided single‐screw extrusion

A novel environmentally friendly process for decrosslinking of the peroxide crosslinked HDPE (XHDPE) via ultrasonic assisted single (SSE) is developed and its process characteristics are established. The specific ultrasonic energy decreases with the flow rate and increases with the ultrasonic amplitude, while die pressure increases with the flow rate and decreases with the ultrasonic amplitude. Application of ultrasonic treatment during extrusion enables an increase of productivity. Gel fraction, crosslink density, dynamic and mechanical properties, and thermal behavior of the virgin HDPE, XHDPE, and decrosslinked XHDPE are measured. Gel fraction and crosslink density of the decrosslinked XHDPE are decreased with increasing flow rate and ultrasonic amplitude. A unique linear relation between the normalized gel fraction and the normalized crosslink density is found, regardless of the type of extruders and processing conditions. SEM images reveals that the decrosslinked XHDPE is a composite of submicron size gel particles embedded in its sol matrix. The sol extracted from the decrosslinked XHDPE exhibits a higher complex viscosity and higher level of branching than the virgin HDPE. An increase of the ultrasonic amplitude leads to a decrease of the complex viscosity, storage and loss moduli, and an increase of the loss tangent of the decrosslinked XHDPE. The thermal behavior and mechanical properties of the decrosslinked XHDPE show a weak dependency on processing conditions. At some processing conditions, mechanical properties of the decrosslinked XHDPE are close or higher to those of XHDPE. POLYM. ENG. SCI., 54:2715–2730, 2014. © 2013 Society of Plastics Engineers

Increasing coal quality by oil agglomeration after ultrasonic treatment

In the present study, oxidized and high sulphur fine coal was subjected to oil agglomeration process after ultrasonic treatment. Power and time of ultrasonic treatment were selected as variable. Combustible recovery, ash rejection, pyritic sulphur rejection, ash separation efficiency and pyritic sulphur separation efficiency of the agglomeration process with and without ultrasonic treatment were determined. In addition, calorific value of the clean coal produced by agglomeration process was measured. In the agglomeration process without ultrasonic treatment, calorific value, combustible recovery, ash rejection and pyritic sulphur rejection were obtained to be 6518kcal/kg, 63.78%, 75.19% and 92.64%, respectively. Ultrasonic treatment enhanced the performance of oil agglomeration process. By the application of ultrasonic treatment before agglomeration process, calorific value, combustible recovery, ash rejection and pyritic sulphur rejection were increased to maximally 6939kcal/kg, 66.13%, 87.24% and 97.44%, respectively. In the study, changes on the surface structure of the coal after ultrasonic treatment were also examined. Particle breakage, formation of cracks and cavities, and altering of surfaces into fresh-clean surfaces were observed. Increase in time and power of ultrasonic treatment had slight positive effect on ash and pyritic sulphur rejections.

Practical Considerations on the Application of Ultrasonic Treatment to Mg-Al Shape Castings

This paper investigates the use of ultrasonic treatment on the grain refinement of Mg-Al alloys in castings similar to commercial gravity castings. It shows that it is a very effective form of grain refinement but it is limited spatially and by the advancing solidification front if partially-solidified product is washed into the die. It was found that the best way to obtain a homogeneous fine grain size through-out the casting was to combine a grain refining addition, SiC, with ultrasonic treatment during the initial stages of solidification.

Tailored One- and Two-Dimensional Self-Assembly of a Perylene Diimide Derivative in Organic Solvents

We report on studies of the tailored self-assembly of the perylene diimide derivative, N,N'-ditridecylperylene-3,4,9,10-tetracarboxylic diimide, into structures with fibrous gel-type, one-dimensional, and two-dimensional morphologies. This approach for producing highly ordered nanostructures of well-defined morphologies utilizes a property of π-conjugated molecules to assemble in poor organic solvents due to π-π interaction between the aromatic cores and takes advantage of the temperature dependence of solubility. The morphology control is based on a fine-tuning of anisotropic, intermolecular solute-solute interactions that are attenuated by the solute-solvent interaction in organic solvents of different chemical structure. We discuss the role of light illumination in the self-assembly process as well as application of ultrasonic treatment as a way of mechanical tailoring of morphology. This approach paves the way toward the molecular-scale tailoring of structural properties of organic semiconducting materials for electronic and optoelectronic applications.