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Number of results: 28
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Authors and Affiliations

Dariusz Wawrzyniak
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Abstract

The research into the occurrence of herbivorous heteroptera of Orthops genus on Sosnowski’s hogweed (Heracleum sosnowskyi Manden.) was carried out over 1999–2002 in the vicinity of Bydgoszcz. The analysis of the faunistic material collected of Heteroptera order showed the occurrence of 3 species where dominant heteroptera were represented by: Orthops campestris L. (48.57%) and Orthops kalmi L.(44.91%), while Orthops basalis Costa was scarce. The maximum abundance of these species coincided with full flowering and the beginning of hogweed fruit formation.

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Authors and Affiliations

Danuta Wrzesińska
Maria Wawrzyniak
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Abstract

Water extractsfrom selected Geraniaceae plants, to which paraffin oil was added as adjuvant, were tested. It was observed that the plant extracts researched limited Colorado potato beetle feeding and development and adding adjuvant increased the effects. The highest antifeedant activity towards Colorado potato beetlesand their larvae wasobs erved in extractsobtained from Pelargonium × hortorum Bailey and Geranium pusillum L. The extract from Pelargonium × hortorum Bailey added to food showed a negative effect on the development of female reproductive organs and embryo development and showed the highest effectiveness in field conditions.

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Authors and Affiliations

Robert Lamparski
Maria Wawrzyniak
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Abstract

The aim of this study was to provide an estimation of climate variability in the Hornsund area in Southern Spitsbergen in the period 1976-2100. The climatic variables were obtained from the Polar-CORDEX initiative in the form of time series of daily air temperature and precipitation derived from four global circulation models (GCMs) following representative concentration pathways (RCP) RCP 4.5 and RCP 8.5 emission scenarios. In the first stage of the analysis, simulations for the reference period from 1979 to 2005 were compared with observations at the Polish Polar Station Hornsund from the same period of time. In the second step, climatic projections were derived and monthly and annual means/sums were analysed as climatic indices. Following the standard methods of trend analysis, the changes of these indices over three time periods - the reference period 1976-2005, the near-future period 2021-2050, and far-future period 2071-2100 - were examined. The projections of air temperature were consistent. All analysed climate models simulated an increase of air temperature with time. Analyses of changes at a monthly scale indicated that the largest increases were estimated for winter months (more than 11°C for the far future using the RCP 8.5 scenario). The analyses of monthly and annual sums of precipitation also indicated increasing tendencies for changes with time, with the differences between mean monthly sums of precipitation for the near future and the reference period similar for each months. In the case of changes between far future and reference periods, the highest increases were projected for the winter months.
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Authors and Affiliations

Marzena Osuch
Tomasz Wawrzyniak
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Abstract

Binary vapour-liquid equilibrium of thymoquinone and carbon dioxide at the isothermal conditions was carried out at temperature 323.15 K and pressures from 6 to 10 MPa. The experimental data were fitted to the Soave-Redlich-Kwong equation of state. Results could be used for selection of process parameters in separation of volatiles from raw oil or for evaluation of existing separation technologies.

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Authors and Affiliations

Karina Gurgenova
Rafał Bogeł-Łukasik
Paweł Wawrzyniak
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Abstract

The role of seeds is crucial in tree production and development, and the future of forests depends on them. But what impact is climate change having on the seed life cycle? Will the trees that grow out of them manage to survive and adapt to the new environment?

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Authors and Affiliations

Mikołaj Wawrzyniak
Ewelina Ratajczak
Ewa Kalemba
Paweł Chmielarz
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Abstract

W pracy analizowano wyniki pomiarów laboratoryjnych wykonanych na próbkach o zróżnicowanej litologii. Głównym celem było sprawdzenie, jak zmieniają się wartości prędkości fal sprężystych i dynamicznych modułów sprężystych w trójosiowym stanie naprężenia. Pomiary wykonano z wykorzystaniem nowatorskiego zestawu będącego na wyposażeniu Katedry Geofizyki, WGGiOŚ, AGH. Zestaw pomiarowy składa się z komory ciśnieniowej, prasy hydraulicznej i dźwigu oraz generatora fal sprężystych i specjalistycznego oprogramowania. Umożliwia pomiary prędkości fal podłużnych P i poprzecznych S wraz z pełną charakterystyką naprężeniowo-odkształceniową w trójosiowym stanie naprężenia. W pracy przedstawiono wyniki pomiarów uzyskane dla ciśnień okólnych odpowiednio dobranych dla głębokości występowania oraz wieku poszczególnych próbek. Pomiary wykonywano do momentu zniszczenia próbki. Wykonano analizę zmian prędkości przy stopniowym osiowym obciążaniu próbki. W efekcie uzyskano prędkości fal sprężystych oraz charakterystyki naprężeniowo-odkształceniowe. Uzyskano wyższe wartości prędkości fal sprężystych przy symulowanych ciśnieniach złożowych niż podczas pomiarów w warunkach atmosferycznych. Wyniki zestawiono z pozostałymi, dostępnymi rezultatami badań laboratoryjnych, np. porowatościami wyznaczonymi z eksperymentów NMR i porozymetrii rtęciowej. Równoczesne pomiary prędkości fal sprężystych P i S oraz charakterystyka naprężeniowo-odkształceniowa przy symulowanym ciśnieniu górotworu są efektywnym narzędziem do odtworzenia w laboratorium warunków złożowych i uzyskania wiarygodnych wartości dynamicznych i statycznych parametrów sprężystych i geomechanicznych.

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Authors and Affiliations

Edyta Puskarczyk
Paulina Krakowska
Kamila Wawrzyniak-Guz
Jadwiga Jarzyna
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Abstract

Rola nasion jest kluczowa w procesach produkcji i rozwoju drzew. To od nich zależy przyszłość lasów. Jaki wpływ na cykl życiowy nasion mają zmiany klimatu? Czy drzewa, które z nich wyrosną, przetrwają i adaptują się do nowego środowiska?

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Authors and Affiliations

Mikołaj Wawrzyniak
Ewelina Ratajczak
Ewa Kalemba
Paweł Chmielarz
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Abstract

Chemical heat pumps (CHP) use reversible exothermal and endothermal chemical reactions to increase the temperature of working fluids. In comparison to the “classical” vapour compression chemical heat pumps, CHP enables us to achieve significantly higher temperatures of a heated medium which is crucial for the potential application, e.g. for production of superheated steam. Despite the advantages presented, currently, there are no installations using CHP for lowgrade waste heat recovery available on the market. The scaling up of industrial processes is still one of the greatest challenges of process engineering. The aim of the theoretical and experimental concept study presented here was to evaluate a method of reclaiming energy from low temperature waste streams and converting it into a saturated steam of temperature from 120 to 150 ◦C, which can be useful in industry. A chemical heat pump concept, based on the dilution and concentration of phosphoric acid, was used to test the method in the laboratory scale. The heat of dilution and energy needed for water evaporation from the acid solutionwere experimentally measured. The cycle of successive processes of dilution and concentration has been experimentally confirmed. A theoretical model of the chemical heat pump was tested and coefficient of performance measured.

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Authors and Affiliations

Marzena Czapnik
Michał Tylman
Maciej Jaskulski
Paweł Wawrzyniak
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Abstract

The thermal state of permafrost is a crucial indicator of environmental changes occurring in the Arctic. The monitoring of ground temperatures in Svalbard has been carried out in instrumented boreholes, although only few are deeper than 10 m and none are located in southern part of Spitsbergen. Only one of them, Janssonhaugen, located in central part of the island, provides the ground temperature data down to 100 m. Recent studies have proved that significant warming of the ground surface temperatures, observed especially in the last three decades, can be detected not only just few meters below the surface, but reaches much deeper layers. The aim of this paper is evaluation of the permafrost state in the vicinity of the Polish Polar Station in Hornsund using the numerical heat transfer model CryoGrid 2. The model is calibrated with ground temperature data collected from a 2 m deep borehole established in 2013 and then validated with data from the period 1990-2014 from five depths up to 1 m, measured routinely at the Hornsund meteorological station. The study estimates modelled ground thermal profile down to 100 m in depth and presents the evolution of the ground thermal regime in the last 25 years. The simulated subsurface temperature trumpet shows that multiannual variability in that period can reach 25 m in depth. The changes of the ground thermal regime correspond to an increasing trend of air temperatures observed in Hornsund and general warming across Svalbard.
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Authors and Affiliations

Tomasz Wawrzyniak
Marzena Osuch
Jarosław Napiórkowski
Sebastian Westermann
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Abstract

Fresh water is essential for life. More and more countries around the world are facing scarcity of drinking water, which affects over 50% of the global population. Due to human activity such as industrial development and the increasing greenhouse effect, the amount of drinking water is drastically decreasing. To address this issue, various methods of sea and brackish water desalination are used. In this study, an energy analysis (specific energy consumption, SEC) of two laboratory membrane processes, reverse osmosis (RO) and pervaporation (PV), was conducted. A model feed system saline water at 0.8, and 3.5% wt. NaCl was used. The efficiency and selectivity of membranes used in PV and RO were examined, and power of the devices was measured. The desalination processes were found to have a high retention factor (over 99%) for both PV and RO. For PV, the permeate fluxes were small but they increased with increasing feed flow rate, process temperature and salt content in the feed. The calculated SEC values for both laboratory processes ranged from 2 to 70 MWh/m 3. Lowering the process temperature, which consumes 30 to 60% of the total energy used in the PV process, can be an important factor in reducing energy consumption.
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Authors and Affiliations

Izabela Gortat
1
ORCID: ORCID
Joanna Marszałek
1
ORCID: ORCID
Paweł Wawrzyniak
1

  1. Lodz University of Technology, Faculty of Process and Environmental Engineering, Wólczańska 213, 93-005 Łódź, Poland
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Abstract

The study was undertaken to determine the effect of continuation or changes of the diet on the morphometry and histomorphometry of bone in male and female Wistar rats with experimen- tally induced obesity by high energetic diet. Sixty-four 90-day-old Wistar rats obtained from obese parents (16 male, 16 female) and control parents (16 male, 16 female) were used in this study. After 21 days of the baby period, rats were divided into four groups: obese rats fed with high energy feed (F/F), control rats fed with a standard diet (C/C), obese rats with changed diet from high energy diet to control diet (F/C) and control rats with changed diet from control diet to high energy diet (C/F). After 90 days of experimental feeding, the rats were sacrificed. Thereafter, body weight and the isolated humerus were measured and next, the histological stainings and counts were done. Our results revealed that change in the parent’s diet from F to C in the female leads to increased bone growth length and reduction of body weight in female and male. Reverse diet changes (from C to F) lead to decreased bone length only in the female. Moreover, the con- tinuation by offspring of both sexes with a high-energy diet contributes to a reduction in osteo- cytes, reduction in bone marrow cavity and cortical expansion, but a change in nutrition from parents’ standard diet to high-energy diet leads to increase in osteocytes dimensions. The contin- uation of feeding with F diet promotes the accumulation of adipocytes in the bone marrow in female and male, and correction of nutrition from F to standard diet leads to a reduction in their number in the bone marrow compared to groups continuing feeding with high-energy diet.

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Authors and Affiliations

D. Wolski
A. Wawrzyniak
M. Bieńko
J. Michalik
R.P. Radzki
M.B. Arciszewski
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Abstract

Calretinin (CR), a calcium-binding protein from EF-hand family, is localised in non-pyramidal GABA-ergic interneurons of the hippocampus. CR takes part in maintaining calcium binding homeostasis, which suggests its neuroprotective role. Hippocampal neurons contain membrane transient receptor potential vanilloid 1 (TRPV1) which binds to capsaicin (CAP) contained in habanero pepper fruits. Few in vivo studies have revealed the effect of CAP on interneurons containing CR. The aim of the present study was to investigate the CR immunoreac- tivity in interneurons of the hippocampal CA1 field and dentate gyrus (DG) in adult rats after intragastric admin- istration of the habanero pepper fruits. Wistar rats received a peanut oil – control group (C), and oil suspension of habanero pepper fruits at doses of 0.025 g dm/kg b.w. – group I and 0.08 g dm/kg b.w. – group II for 28 days. After euthanasia, the brains were collected and embedded in paraffin blocks using a routine histological tech- nique. Frontal hippocampal sections were immunohistochemically stained for CR by using a peroxidase-antiper- oxidase method. CR immunoreactive (CR-IR) interneurons were morphologically and morphometrically ana- lyzed under a light microscope. The results showed similar shapes and distribution of cells in both areas of the brain in group C and I of animals. However, CR-IR interneurons in the hippocampal CA1 field and in DG were occasionally observed in the group II of rats.

The results of morphometric studies did not reveal statistically significant differences in the surface area and shape index of cells between examined brain regions from groups I and II compared to group C.

Only in group II of rats, an increase in the digital immunostaining intensity of CR-IR interneurons was found in DG. Low number of CR-IR interneurons in the hippocampal CA1 field and in the DG, under the influence of a large dose of habanero pepper fruits containing CAP, may be caused by the activation of TRPV1 receptors and the increase in Ca2+ ions in these cells. This phenomenon may ultimately lead to neuronal death and may disturb neuronal conduction.

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Authors and Affiliations

J. Jaworska-Adamu
A. Krawczyk
K. Rycerz
M. Gołyński
A. Wawrzyniak
K. Lutnicki
I. Balicki
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Abstract

In this work, the influence of plastic injection molding conditions, mainly plasticizing conditions: plasticizing pressure (back pressure) and decompression (suck-back) after dosing on weight, thickness, mechanical properties and structure of HDPE parts obtained by injection molding with the addition of chemical blowing agent was done. In order to enable the manufacturing of correctly made molded parts under given plasticizing conditions, other parameters (hold time and hold pressure, injection velocity and injection time) were also changed. It was found that making correct molded parts using decompression requires increased hold pressure and hold time. The share of the porous structure in the parts is inversely proportional to the decompression as well as the hold pressure and hold time, while the plasticizing pressure has little effect on thickness, mass, tensile strength and elongation at maximum force, however, it affects the structure of the molded parts to some extent.
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Authors and Affiliations

P. Palutkiewicz
1
ORCID: ORCID
P. Postawa
1
ORCID: ORCID
J. Wawrzyniak
1
ORCID: ORCID

  1. Czestochowa University of Technology, Faculty of Mechanical Engineering and Computer Science, Department of Technology and Automation, 21 Armii Krajowej Av., 42-201 Czestochowa, Poland
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Abstract

Round goby (Neogobius melanostomus (Pallas, 1814)) is an invasive species in the Oder River. In this study, age of 147 fish was determined using scales and otoliths, and the Fraser-Lee back-calculation method was used for population structure and theoretical length growth rates with 3 mathematical models of growth: von Bertalanffy, Ford–Walford and 2nd degree polynomial. Fish condition was determined using Fulton, Le Cren and Clark equations. Average total length and weight of fish was 162.00 mm and 83.00 g, respectively. Males were more abundant than females, representing 70% of the fish caught, and achieved greater total lengths and weights. Age 2+ dominated females and 3+ males age groups. Of the three mathematical models used to estimate fish growth, the 2nd degree polynomial model had the best fit to back-calculated lengths. Males had slightly higher growth rates than females in the first two years of life but comparable in subsequent years. The diet consisted of various benthic organisms that varied with fish age. The most frequently occurring food com-ponent was Dreissena polymorpha, which accounted for approximately 70% in the diet of fish with a body length greater than 191 mm.

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Authors and Affiliations

Agnieszka Rybczyk
ORCID: ORCID
Przemysław Czerniejewski
ORCID: ORCID
Sławomir Keszka
Mariola Janowicz
Adam Brysiewicz
ORCID: ORCID
Wawrzyniec Wawrzyniak
ORCID: ORCID

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