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Himalayan nettle: a promising fibre on the rise
No full textThe nettle is widely known as an "unloved" plant due to its unpleasant and even painful texture when
incorrectly handled. However, it has very interesting therapeutic properties and stands out for its high
sustainability, from cultivation, extraction, and fibre processing to the development of a long-lasting
end-product with unique characteristics.
With this paper we sought to demonstrate the growing relevance of the nettle fibre for the fashion
industry, mainly their spinnability properties. For this purpose, a hand spun Himalayan nettle yarn
(588,24 Tex) was bought and it were studied. A woven fabric with different wool/nettle compositions
was produced and their main properties analysed. Our findings proved that due to the irregularity of the
acquired yarn, it is not possible to obtain scientific statements concerning the properties of nettle yarn.
However, this is a work in progress, which aims for more promising results
Innovative thermally stablized low twist hybrid yarns from recycled carbon fibre for thermosplastic composites
No full textHybrid yarns consisting of rCF and thermoplastic fibre offer a good potentials to improve mechanical
properties of carbon fibre reinforced composites due to high fiber length, homogeneous mixing and high
rCF content [1]. However, the twisting of the yarn in conventional spinning processes leads on one hand
to the damage in rCF during spinning because of its high brittleness and sensitivity to shear forces. On
the other hand, mechanical properties e.g. tensile and flexural strengths of composites decrease
significantly with the increase of twist as a result of low fibre orientation [2]. On the contrary, the yarn
strength and the stability of the spinning process are strongly dependent on the level of yarn twist. In
our previous paper [3], the development of low twist hybrid yarns (75-30 T/m) consisting of rCF and
polyamide 6 (PA6) fibre for high performance thermoplastic composites has been reported. However,
hybrid yarns with low twist levels suffer from low spinning stability and poor yarn strength, which limits
their further processablity in weaving or knitting processes. Therefore, the focus of this work is the
development of a method to reduce yarn twist but still ensuring a stable spinning process, high yarn and
composite strengths
In-situ stress analysis of fiber reinforced plastics under bending load until failure by using integrated textile-based piezoresistive sensors
No full textThe application of fiber reinforced composites (FRC) for load-bearing and safety-relevant components
requires regular inspections to assess the structural conditions. A suitable solution are integrated textilebased
piezoresisitive sensors for structural health monitoring applications. This research work focusses
on the evaluation and comparison of the electromechanical strain sensing behaviour of steel wires and
carbon fibers on the fiber and composite scale. The electromechanical properties are investigated by
using a uniaxial fiber tensile test with a simultaneous electrical resistance measurement. Glass fiber
reinforced plastic (GFRP) specimen with in-situ sensors are tested in quasistatic and cyclic three-point
bending tests. The acquired sensor signals are used for a comprehensive stress analysis and better
understanding of the failure behaviour. The cyclic testing procedure showed reproducible sensor signals
The quality of the night sky in astronomical observatories based on monitoring by the ALPS network
No full textPolska jest krajem o dużym i narastającym zanieczyszczeniu
światłem. Dla astronomii jakość nocnego nieba, na którą w istotny sposób
wpływa zanieczyszczenie światłem, jest kluczowa dla możliwości prowadzenia
badań naukowych. ALPS to sieć automatycznych stacji przeznaczonych do
ciągłego monitoringu nieba. Stacje te rejestrują obrazy całego nieba oraz
dokonują pomiaru jego jasności. Znajdują się one obecnie głównie w obserwatoriach
astronomicznych. Głównym celem projektu jest badanie poziomu
jasności nocnego nieba z uwzględnieniem warunków meteorologicznych oraz
śledzenie zmian i źródeł zanieczyszczenia światłem.
Na podstawie zebranych dotychczas danych ALPS określony został stopień
degradacji nocnego nieba w obserwatorium astronomicznym w Białkowie,
obserwatorium astronomicznym w Piwnicach i obserwatorium astronomicznym
w Sopotni Wielkiej. Otrzymane wyniki pokazują, że konieczne jest pilne
podjęcie działań mających na celu ochronę nocnego nieba nad obserwatoriami
astronomicznymi w Polsce.Poland is a country with high and increasing light pollution. For
astronomy, the quality of the night sky, which can be significantly affected by
light pollution is crucial to the conduct of scientific research.
ALPS is a network of automatic stations designed for continuous monitoring of
the sky. The stations record images of the entire sky and measure its
brightness. At present, they are mainly located in astronomical observatories.
The main goal of the project is to study the brightness of the night sky, taking
into account meteorological conditions, and to track changes and sources of
light pollution.
Based on the ALPS data collected so far, the degree of night sky degradation
in the astronomical observatory in Białków, the astronomical observatory in
Piwnice and the astronomical observatory in Sopotnia Wielka was determined.
The results obtained show that urgent measures are needed to protect the
night sky over astronomical observatories in Poland
The Potential of Using Blockchain Technology in the Area of Stakeholder Relationships
No full textOrganisations should look after the interests and meet the expectations
of a wide range of stakeholders. Therefore, it is necessary to properly shape
that relationship. Stakeholder relationship management can be supported by
emerging technologies such as blockchain. This study focuses on the potential
associated with using this technology in the area of stakeholder relationshi
Comparison of bacterial cellulose produced from nata-de-coco and kombucha
No full textIn the current study, two different bacterial cellulose including nata-de-coco bacterial cellulose (NBC)
and kombucha bacterial cellulose (KBC) were compared. The morphological features, functional groups
and crystals were carried out by scanning electron microscopy (SEM), attenuated total reflectance
Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD). Thermogravimetric
analysis was used to investigate the stability. Mechanical property and water content were evaluated by
tensile strength tester and gravimetric method. Results revealed slightly loose fibril arrangement in KBC
compared to NBC. The crystallinity, thermal and mechanical properties of KBC were lower than those
of NBC. Water content of KBC was slightly higher than that of NBC
Effect of light pollution on the physiology of city bird
No full textGlobalny postęp urbanizacji jest przyczyną ciągłego wzrostu
skażenia światłem, które staje się coraz większą uciążliwością nie tylko dla
ludzi, ale także dla pozostałych mieszkańców miasta, tj. flory i fauny. W miarę
poznawania szkodliwości skażenia światłem dla zdrowia i funkcjonowania
organizmu człowieka, mechanizmy uczestniczące w zakłócaniu rytmów dobowych
i syntezy melatoniny przez nocne światła miejskie stają się powoli
zrozumiałe. Natomiast w odniesieniu do zwierząt zamieszkujących miasta
wiedza ta jest ciągle raczej skromna. Celem niniejszego opracowania jest
przegląd istniejących badań dotyczących fizjologii i behawioru ptaków
śpiewających zaadaptowanych do życia w skażonych światłem miastach. Aby
jednak mieć wgląd w uczestniczące w tym mechanizmy molekularne,
przedstawiono także wyniki badań eksperymentalnych prowadzonych
w warunkach laboratoryjnych.Globally progressing urbanization generates a continuous increase in
light pollution which become more and more oppressive not only for humans
but also for other city dwellers, i.e. flora and fauna. With advances in the
research on the noxious effect of light pollution on human physiology and
health, the mechanisms involved in the disruption of diurnal rhythms and
melatonin synthesis by the light at night slowly start to be understood. On the
contrary, similar knowledge concerning city-dwelling animals is still rather
scarce. The aim of the present chapter is to summarize available data on the
physiology and behavior of the songbird species adapted to life in lightpolluted
cities. To have an insight into the molecular mechanisms involved in
these adaptations, the results of experimental data obtained in the laboratory
conditions are also presented
