scholarly journals Theoretical Basis and Experimental Means of the Hydrophilic Nanostructure Formation Process on the Titanium Surface by Direct Laser Irradiation

2018 ◽  
Author(s):  
Sharif E. Guseynov ◽  
Jekaterina V. Aleksejeva ◽  
Ruslans Aleksejevs ◽  
Uldis Zaimis
Keyword(s):  
Laser Irradiation ◽  
Formation Process ◽  
Theoretical Basis ◽  
Titanium Surface ◽  
Nanostructure Formation ◽  
Direct Laser

Two- and Three-Dimensional Photonic Crystals Produced by Pulsed Laser Irradiation in Silver-Doped Glass

2004 ◽  
Vol 99-100 ◽  
pp. 65-72
Author(s):  
Yuri S. Kaganovsky ◽  
I. Antonov ◽  
M. Rosenbluh ◽  
J. Ihlemann ◽  
A.A. Lipovskii
Keyword(s):  
Photonic Crystals ◽  
Laser Irradiation ◽  
Uv Irradiation ◽  
Elevated Temperatures ◽  
Pulsed Laser ◽  
Silver Nanoclusters ◽  
Direct Laser ◽  
Doped Glass ◽  
2D And 3D ◽  
Pulsed Laser Irradiation

Two types of silver-doped glass were used for direct laser recording of 2D and 3D photonic crystals. The first contained a diffusion layer (20 microns thick) with embedded silver nanoclusters of 20-nm average radius. 2D and 3D photonic crystals of submicron lattice parameters were fabricated by nanosecond pulsed laser irradiation (l, = 355 nm) using four or five coherent intersecting beams. Under irradiation the clusters absorbing light energy are heated to high temperatures and become mobile due to the formation of liquid shells around them. Adjacent clusters move towards each other and towards the irradiated surface under local temperature gradients, form agglomerates and merge in periodically located "spots" of high light intensity in the interference field. The second type of glass, photosensitive to UV irradiation, contained in the bulk Ag+ and Ce3+ ions. Under UV irradiation excited electrons passed from Ce3+ to Ag+. The Ag atoms became neutral and under subsequent heat treatment of the glass at elevated temperatures have a tendency to form nanoclusters, thus “developing” the UV recorded patterns. Using nanosecond pulsed irradiation of 308 nm we have recorded 3D photonic crystals in the bulk of such glass.

scholarly journals Subjunctive aspects of sociological support of the modern teacher formation process in the development context of the new Ukrainian school system

2021 ◽  
Vol 5 (S1) ◽  
pp. 439-450
Author(s):  
Natalia Hlebova ◽  
Karina Oleksenko ◽  
Roman Oleksenko ◽  
Lyudmila Afanasieva
Keyword(s):  
Formation Process ◽  
School System ◽  
Theoretical Basis ◽  
Mutual Influence ◽  
Educational Communication ◽  
Educational Process ◽  
Teacher Formation ◽  
Modern School ◽  
Development Context ◽  
Potential Factors

Purpose. Consider the subjunctive aspects of sociological support of the modern teacher formation process in the development context of the New Ukrainian School system. Theoretical basis. Theoretical basis is social and humanistic concepts of socio-philosophical, cultural, sociological, social and psychological approaches to the study of social factors in full Ukrainian school graduate adaptation in the broad context of socio-cultural realities. Scientific novelty. Based on the sociological design methodology and empirical research materials analysis of the educational and pedagogical environment state, an attempt has been made to identify the possibility of sociological procedures integration to identify the mutual influence of the educational process subjects in the modern school. Findings. It is summarized that such forms of modern teacher feedback on methods and work results as sociological assessment of stakeholder positions is an important aspect of supporting the new Ukrainian school development process. Based on the sociological assessment of priority mechanisms to improve the teaching efficiency, the respondents' qualification level as information network users and potential factors for improving their skills, the topical directions for increasing the productivity of using social networks for educational communication were identified.

Preparation of multifunctional porous carbon electrodes through direct laser writing on a phenolic resin film

2019 ◽  
Vol 7 (37) ◽  
pp. 21168-21175 ◽  
Author(s):  
Junbo Liu ◽  
Lijing Zhang ◽  
Cheng Yang ◽  
Shengyang Tao
Keyword(s):  
Laser Irradiation ◽  
Joule Heating ◽  
Porous Carbon ◽  
Phenolic Resin ◽  
Carbon Materials ◽  
Electrochemical Sensors ◽  
Carbon Electrodes ◽  
Direct Laser Writing ◽  
Direct Laser ◽  
Porous Carbon Electrodes

Multifunctional porous carbon materials prepared by laser irradiation on a phenolic resin were engineered into electrochemical sensors, microsupercapacitors, and Joule-heating devices.

scholarly journals Efficacy of Er:YAG laser irradiation for decontamination and its effect on biocompatibility of different titanium surfaces

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Peijun Huang ◽  
Xue Chen ◽  
Zhongren Chen ◽  
Min Chen ◽  
Jinzhi He ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Laser Irradiation ◽  
Titanium Surface ◽  
Er:Yag Laser ◽  
Fluorescent Detection ◽  
Microbial Biofilm ◽  
Optimal Energy ◽  
Wide Range ◽  
Proliferation Activity ◽  
Titanium Surfaces

Abstract Background Erbium yttrium–aluminum–garnet (Er:YAG) laser have been shown to be suitable for decontamination of titanium surfaces at a wide range of energy settings, however, high intensity of laser irradiation destroy titanium surface and low intensity cannot remove enough microbial biofilm. The aim of this study was to investigate the optimal energy setting of Er:YAG laser for decontamination of sandblasted/acid-etched (SLA) and hydroxyapatite (HA) titanium surfaces. Material and methods After supragingival biofilm construction in vivo, SLA and HA titanium discs were divided into three groups: blank control (BC, clean discs), experimental control (EC, contaminated discs) and experimental groups (EP, contaminated discs irradiated by Er:YAG laser at 40, 70, and 100 mJ/pulse). Scanning electron microscopy (SEM), live/dead bacterial fluorescent detection, and colony counting assay were used to detect the efficacy of laser decontamination. To investigate the effect of laser decontamination on titanium surface biocompatibility, MC3T3-E1 cell adhesion and proliferation activity were examined by SEM and CCK-8 assay. Results Er:YAG laser irradiation at 100 mJ/pulse removed 84.1% of bacteria from SLA titanium surface; laser irradiation at 70 and 100 mJ/pulse removed 76.4% and 77.85% of bacteria from HA titanium surface respectively. Laser irradiation improved MC3T3-E1 cell adhesion on both titanium surfaces. For SLA titanium discs, 100 mJ/pulse group displayed excellent cellular proliferation activity higher than that in BC group (P < 0.01). For HA titanium discs, 70 mJ/pulse group showed the highest activity comparable to BC group (P > 0.05). Conclusions With regards to efficient microbial biofilm decontamination and biocompatibility maintenance, Er:YAG laser at 100 mJ/pulse and 70 mJ/pulse are considered as the optimal energy settings for SLA titanium and HA titanium surface respectively. This study provides theoretical basis for the clinical application of Er:YAG laser in the treatment of peri-implantitis.

scholarly journals Formation of the oxide coating on the titanium surface by multipulse femtosecond laser irradiation

2018 ◽  
Vol 1115 ◽  
pp. 042066
Author(s):  
M V Zhidkov ◽  
E V Golosov ◽  
T N Vershinina ◽  
S I Kudryashov ◽  
Yu R Kolobov ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Titanium Surface ◽  
Oxide Coating ◽  
Femtosecond Laser Irradiation

Thermal Convection and Stress Analysis of the Cooling System for a Terahertz Radiation Detector

2015 ◽  
Author(s):  
Angela Wu ◽  
Arturo Pacheco-Vega ◽  
Jeanette Cobian
Keyword(s):  
Fluid Flow ◽  
Laser Irradiation ◽  
Cooling System ◽  
Rectangular Channel ◽  
Radiation Detector ◽  
Three Dimensional ◽  
Operating Conditions ◽  
Temperature Fields ◽  
Stress Strain ◽  
Direct Laser

Detailed three-dimensional numerical simulations have been carried out to find the velocity and temperature fields, in combination with shear and normal stresses, of the fluid flow inside a rectangular channel with large aspect-ratio. The channel under analysis is aimed to cool a thermochromic liquid crystal material (TLC) that is able to capture laser irradiation in the terahertz range. The TLC is manufactured on an extremely-thin substrate. The overall objective of the cooling system is to maintain a nearly-homogeneous temperature of the TLC-domain that is not exposed to the direct laser irradiation, while minimizing the deformation in the TLC caused by the fluid-solid interaction. The fluid flow, stress-strain and heat transfer simulations are carried out on the basis of three-dimensional Navier-Stokes and energy equations for an incompressible flow, coupled with the stress-strain equation for the TLC-layer, to determine values of velocity, pressure and temperature for the fluid inside the channel and the stresses and deformation of the TLC layer, under different operating conditions. These values are then used to find, from a specific set, the value of the channel gap that enables a nearly-uniform temperature distribution in the fluid and the least amount of deformation in the solid layer, within the expected operating conditions. Results from this analysis indicate that, for all the inlet velocities considered, there is a common value of the channel gap, that represents the optimum for the cooling system.

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