Publications by authors named "Pavels Onufrijevs"

Global energy consumption is increasing yearly, yet the world is trying to move toward carbon neutrality to mitigate global warming. More research is being done on energy storage devices to advance these efforts. One well-known and widely studied technology is Zn-ion batteries (ZIBs).

View Article and Find Full Text PDF

The use of biobased materials in additive manufacturing is a promising long-term strategy for advancing the polymer industry toward a circular economy and reducing the environmental impact. In commercial 3D printing formulations, there is still a scarcity of efficient biobased polymer resins. This research proposes vegetable oils as biobased components to formulate the stereolithography (SLA) resin.

View Article and Find Full Text PDF

Titanium (Ti) is widely recognized for its exceptional properties and compatibility with medical applications. In our study, we successfully formed laser-induced periodic surface structures (LIPSS) on Ti plates with a periodicity of 520-740 nm and a height range of 150-250 nm. To investigate the morphology and chemical composition of these surfaces, we employed various techniques, including field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy.

View Article and Find Full Text PDF

In this work we study the mechanisms of laser radiation interaction with elementary semiconductors such as Si and Ge and their solid solution SiGe. As a result of this investigation, the mechanisms of nanocones and microcones formation on a surface of semiconductor were proposed. We have shown the possibility to control the size and the shape of cones both by the laser.

View Article and Find Full Text PDF

In this work, we study the mechanism of nanocone formation on a surface of elementary semiconductors by Nd:YAG laser radiation. Our previous investigations of SiGe and CdZnTe solid solutions have shown that nanocone formation mechanism is characterized by two stages. The first stage is characterized by formation of heterostructure, for example, Ge/Si heterostructure from SiGe solid solutions, and the second stage is characterized by formation of nanocones by mechanical plastic deformation of the compressed Ge layer on Si due to mismatch of Si and Ge crystalline lattices.

View Article and Find Full Text PDF

On the basis of the analysis of experimental results, a two-stage mechanism of nanocones formation on the irradiated surface of semiconductors by Nd:YAG laser is proposed for elementary semiconductors and solid solutions, such as Si, Ge, SiGe, and CdZnTe. Properties observed are explained in the frame of quantum confinement effect. The first stage of the mechanism is characterized by the formation of a thin strained top layer, due to redistribution of point defects in temperature-gradient field induced by laser radiation.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessionu349iddrl7vg5vic52ovv3r0vpj6esrs): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once