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1.
Sensors (Basel) ; 24(1)2023 Dec 24.
Article in English | MEDLINE | ID: mdl-38202959

ABSTRACT

The main object of this research was to develop a security system to evaluate the intrusion into an object through a glass pane. More specifically, this study deals with sensing and evaluating signals from a contact glass-break detector, which is part of an intruder alarm system. Each alarm detector in an alarm system must accomplish certain security level requirements that strictly describe the requirements for the area of use and the detector's reliability. To date, no contact glass-break detector has been developed and fully tested to meet the stringent requirements of the highest security level. A contact glass-break detector was developed whose main part is an accelerometer that transmits signals from the glass pane. These signals were evaluated according to the developed methodology. It was verified that the proposed system can distinguish at the highest security level between false alarms and situations where the building has been intruded.

2.
Biotechniques ; 70(5): 263-270, 2021 05.
Article in English | MEDLINE | ID: mdl-33998838

ABSTRACT

Surface plasmon resonance imaging biosensors have a number of advantages that make them superior to other analytical methods. These include the possibility of label-free detection, speed and high sensitivity to low protein concentrations. The aim of this study was to create and analyze biochips, with the help of which it is possible to test cystatin C in patient urine samples and compare the results with the one-time traditional ELISA method. The main advantage of the surface plasmon resonance imaging method is the possibility of repeated measurements over a long period of time in accordance with clinical practice. The surface of the biochip was spotted with anticystatin C and a negative control of mouse IgG at a ratio of 1:1. The aforementioned biochip was first verified using standard tests and then with patient samples, which clearly confirmed the required sensitivity even for very low concentrations of cystatin C.


Subject(s)
Biosensing Techniques , Cystatin C/analysis , Surface Plasmon Resonance , Animals , Cystatin C/urine , Humans , Mice , Microarray Analysis
3.
Materials (Basel) ; 13(13)2020 Jun 29.
Article in English | MEDLINE | ID: mdl-32610497

ABSTRACT

This study describes the effect of electron radiation on the nano-mechanical properties of surface layers of selected polyamide (PA) types. Electron radiation initiates the cross-linking of macromolecules in the polyamide structure, leading to the creation of a 3D network which fundamentally changes the properties of the tested polymers. Selected types of polyamide (PA 6, PA 66 and PA 9T) were exposed to various intensities of electron radiation (33 kGy, 66 kGy, 99 kGy, 132 kGy, 165 kGy and 198 kGy). The cross-linked polyamides' surface properties were measured by means of the modern nano-indentation technique (Depth Sensing Indentation; DSI), which operates on the principle of the immediate detection of indenter penetration depth in dependence on the applied load. The evaluation was preformed using the Oliver-Pharr method. The effect of electron radiation on the tested polyamides manifested itself in the creation of a 3D network, which led to an increase of surface layer properties, such as indentation hardness, elastic modulus, creep and temperature resistance, by up to 93%. The increase of temperature and mechanical properties substantially broadens the field of application of these materials in technical practice, especially when higher temperature resistance is required. The positive changes to the nano-mechanical properties as well as mechanical and temperature capabilities instigated by the cross-linking process were confirmed by the gel volume test. These measurements lay the foundation for a detailed study of this topic, as well as for a more effective means of modifying chosen properties of technical polyamide products by radiation.

4.
Materials (Basel) ; 13(4)2020 Feb 19.
Article in English | MEDLINE | ID: mdl-32093045

ABSTRACT

This study's goal was to describe the influence of a wide range of ionizing beta radiation upon the changes in surface layer mechanical properties and structural modifications of selected types of polymer. Radiation crosslinking is a process whereby the impingement of high-energy electrons adjusts test sample structures, thus enhancing the useful properties of the material, e.g., hardness, wear-resistance, and creep, in order that they may function properly during their technical use. The selected polymers tested were polyolefin polymers like polyethylene (Low-density polyethylene LDPE, High-density polyethylene HDPE). These samples underwent exposure to electron radiation of differing dosages (33, 66, 99, 132, 165, and 198 kGy). After the crosslinking process, the samples underwent testing of the nano-mechanical properties of their surface layers. This was done by means of a state-of-the-art indentation technique, i.e., depth-sensing indentation (DSI), which detects the immediate change in the indentation depth associated with the applied force. Indeed, the results indicated that the optimal radiation dosage increased the mechanical properties by up to 57%; however, the beneficial levels of radiation varied with each material. Furthermore, these modifications faced examination from the structural perspective. For this purpose, a gel test, Raman spectroscopy, and crystalline portion determination by X-ray all confirmed the assumed trends.

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