Beata Synkiewicz-Musialska, Dorota Szwagierczak, Jan Kulawik and Elżbieta Czerwińska
This paper aims to report on fabrication procedure and presents microstructure and dielectric behaviour of LiZn0.92Cu0.08PO4 ceramic material with Li2CO3 as a sintering aid.
Abstract
Purpose
This paper aims to report on fabrication procedure and presents microstructure and dielectric behaviour of LiZn0.92Cu0.08PO4 ceramic material with Li2CO3 as a sintering aid.
Design/methodology/approach
Substrates based on LiZn0.92Cu0.08PO4 with Li2CO3 addition were prepared via solid-state synthesis, doping, milling, pressing and sintering. Characterization of the composition, microstructure and dielectric properties was performed using X-ray diffractometry, energy dispersive spectroscopy, scanning electron microscopy, impedance spectroscopy in the 100 Hz to 2 MHz range and time-domain spectroscopy in the 0.1–3 THz range.
Findings
Doped LiZnPO4 ceramic, which exhibits a low dielectric constant of 5.9 at 1 THz and low sintering temperature of 800 °C, suitable for low temperature co-fired ceramics (LTCC) technology, was successfully prepared. However, further studies are needed to lower dielectric losses by optimising the doping level, synthesis and sintering conditions.
Originality/value
Search for new low dielectric constant materials applicable in LTCC technology and optimization of processing are essential tasks for developing modern microwave circuits. The dielectric characterization of doped LiZnPO4 ceramic in the terahertz range, which was performed for the first time, is crucial for potential millimetre-wave applications of this substrate material.
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Agata Wawrzyniak, Agnieszka Elżbieta Woźniak, Anna Anyzewska, Małgorzata Kwiatkowska and Anna Kołłajtis-Dołowy
The purpose of this paper is to assess the Questionnaire Eating Behaviours (QEB), developed by the Science Committee of Human Nutrition of the Polish Academy of Sciences, as an…
Abstract
Purpose
The purpose of this paper is to assess the Questionnaire Eating Behaviours (QEB), developed by the Science Committee of Human Nutrition of the Polish Academy of Sciences, as an instrument to examine the opinions on food and nutrition and diet quality indicators in women in various age groups.
Design/methodology/approach
The study involved 161 healthy Polish women aged 18–92, divided into four age groups to assess the QEB questionnaire, as an instrument to examine the opinions on food and nutrition and diet quality indicators.
Findings
Women provided statistically significant responses to 40 per cent of the statements in the test. In the case of 60 per cent of responses proper answers increased with the age of the participant. Questionnaire determines that people whose opinions were more compliant with nutritional knowledge more often applied the principles of proper nutrition. Dependencies between the number of points from the test of opinions about food and nutrition and the Prohealthy-Diet-Index (pHDI-8) or the sum of points from the test and the Non-healthy-Diet-Index (nHDI-8) were indicated. People who obtained the higher pHDI-8 and the lower nHDI-8 coefficient better evaluated their diet.
Originality/value
The QEB questionnaire can be an effective, quick and cheap instrument recommended to examine the association between the opinion about food and nutrition and the quality of diet of people at various ages and useful in determining the directions of further education and improvement in the quality of diet, including its assessment in large population groups.