Wyniki wyszukiwania - Biblioteka Nauki

1

Potwierdzenie występowania Lycia zonaria (DEN. & SCHIFF.) (Lepidoptera: Geometridae) w Polsce

100%

Myskow E. , Zieleniewska M. , Zawisza M.

Wiadomości Entomologiczne

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2014

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tom 33

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nr 3

2

Rigid polyurethane foam composites with vegetable filler for application in the cosmetics industry

88%

Zieleniewska M. , Szczepkowski L. , Krzyżowska M. , Leszczyński M. , Ryszkowska J.

Polimery

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2016

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tom T. 61, nr 11-12

807--814

EN

This study was designed towards the development of rigid polyurethane foam (RPURF) composites for application in the cosmetics industry using ground hazelnut shell waste as filler. Additionally, the influence of the filler content on the structure of the composites, as well as on their physico-mechanical, thermal, and biological properties was investigated. The particle size distribution and chemical structure of the natural filler, was examined. The synthesized foams were analyzed using a variety of techniques such as infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Furthermore, the apparent density, water absorption, dimensional stability, compressive strength, and resistance to aging of the materials were determined. Due to the proposed application, the toxicity analysis of the synthesized materials was essential. The conducted research resulted in the development of the composition and preparation procedure for the synthesis of rigid polyurethane foam biocomposites incorporating a high content of ground hazelnut shell as filler.

PL

Otrzymano kompozyty sztywnych pianek poliuretanowych (RPURF) z udziałem odpadowych łupin orzecha laskowego, odpowiednie do zastosowań w przemyśle kosmetycznym. Określono wpływ zawartości napełniacza na strukturę, właściwości fizykomechaniczne, termiczne oraz biologiczne wytworzonych materiałów. Przeanalizowano wymiary cząstek oraz budowę chemiczną napełniacza. Pianki RPURF scharakteryzowano za pomocą spektroskopii w podczerwieni (FT-IR), analizy termograwimetrycznej (TGA), różnicowej kalorymetrii skaningowej (DSC), skaningowej mikroskopii elektronowej (SEM). Ponadto określono gęstość pozorną kompozytów, ich chłonność wody, stabilność wymiarową, wytrzymałość na ściskanie oraz odporność na warunki starzeniowe. Ze względu na przewidywaną aplikację oceniono też toksyczność pianek. Na podstawie wyników badań opracowano skład oraz metodę wytwarzania biokompozytów sztywnych pianek poliuretanowych z dużym udziałem napełniacza pochodzenia naturalnego w postaci zmielonych łupin orzecha laskowego.

3

The structure and properties of viscoelastic polyurethane foams with FyrolTM and keratin fibers

75%

Zieleniewska M. , Ryszkowska J. , Bryśkiewicz A. , Auguścik M. , Szczepkowski L. , Świderski A. , Wrześniewska-Tosik K.

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tom T. 62, nr 2

127--135

EN

The subject of the research presented in this article is viscoelastic polyurethane foams (VPF) made using a halogen free flame retardant additive – Fyrol™ – and keratin fibers. The foams were made with varying isocyanate index. For their modification, Fyrol PNX LE and Fyrol PNX were used as well as keratin fibers obtained from poultry feathers. Foams were characterized by means of techniques such as infrared spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The changes in the patterns of the foams were analyzed using a scanning electron microscope. Moreover, flammability of selected foams was defined using a cone calorimeter and oxygen index. Compression set of the foams was assessed. As a result, it was concluded that the use of a Fyrol mixture with keratinous fibers preferably reduces permanent deformation of foams and a fire hazard caused by their usage.

PL

Przedmiotem badań omówionych w artykule są poliuretanowe pianki wiskoelastyczne (VPF) otrzymane z dodatkiem bezhalogenowego środka uniepalniającego – Fyrol™ – i włókien keratynowych. Pianki wykonano w warunkach różnej wartości indeksu izocyjanianowego. Do ich modyfikacji wykorzystano Fyrol PNX LE (F-LE) i Fyrol PNX (F) oraz włókna keratynowe, pozyskane z piór drobiowych. Pianki charakteryzowano metodami spektroskopii w podczerwieni, analizy termograwimetrycznej, różnicowej kalorymetrii skaningowej oraz mikroskopii skaningowej. Oceniano także palność wybranych pianek na podstawie indeksu tlenowego (OI) oraz przebieg spalania za pomocą kalorymetru stożkowego. Na podstawie odkształcenia trwałego pianek po ściskaniu i OI stwierdzono, że modyfikacja pianek poliuretanowych mieszaniną Fyrolu z włóknami keratynowymi wpływa korzystnie na zmniejszenie odkształcenia trwałego pianek oraz ich palność, a w konsekwencji na ograniczenie zagrożenia pożarowego spowodowanego ich użytkowaniem.

4

Kompozyty poliuretanowe o różnych osnowach napełniane mikrosferami szklanymi

75%

Ryszkowska J. , Zieleniewska M. , Bryśkiewicz A. , Mizera K. , Chrząszcz M. , Kozon D. , Lipert K.

Polimery

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2017

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tom T. 62, nr 1

11--18

PL

Przedmiotem pracy są kompozyty poliuretanowe z dwóch różnych typów poliuretanów napełnianych mikrosferami szklanymi przeznaczone do wytwarzania form stosowanych w technologii odlewania próżniowego (VC). Oceniano wpływ napełniacza na właściwości wytworzonych kompozytów. Wyznaczono lepkość przedmieszek, a usieciowane kompozyty scharakteryzowano metodami analizy termomechanicznej (DMA) oraz analizy struktury z zastosowaniem spektroskopii w podczerwieni (FT-IR) i skaningowej mikroskopii elektronowej (SEM). Przedstawiono również wyniki badań wytrzymałościowych.

EN

The paper concerns composites made of polyurethane materials intended for the production of molds used in the vacuum casting process (VC). Two types of polyurethanes were applied to prepare the composites filled with glass microspheres. The influence of the filler on the properties of the resulting polyurethane composites was investigated. The viscosity of the premixes for the preparation of these composites was determined. The crosslinked composites were characterized using thermomechanical analysis (DMA), while their structure was investigated by infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The results of strength tests are also presented.

5

Performance of a matching pursuit based classifier on vep: a potential parameter for assessment of the state of patients with disorders of consciousness

75%

Dovgialo M. , Chabuda A. , Duszyk A. , Pietrzak M. , Rozanski P. , Zieleniewska M. , Durka P. J.

Acta Neurobiologiae Experimentalis

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2017

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tom 77

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nr Suppl.1

EN

INTRODUCTION: P300 event‑related potential reflects the brain response to external stimuli. Attention paid to one of many repeatedly presented stimuli can be detected from the relative strengths of the responses; if the subject actively counts the occurrences of one of the stimuli (target), specific waveform responsе, namely the P300 potential, may be observed, and it will be absent during the unattended (non‑target) stimuli. This difference can be used as an indicator of conscious information processing in unresponsive patients suffering from disorders of consciousness (DoC). However, P300 waveforms recorded from those patients may significantly differ from the classical shape known from healthy subjects. AIM(S): We test the possibility of replacing the classical indicators used for assessing the difference between responses to target and non-target stimuli by cross-validation of a classifier detecting responses, based upon multivariate matching pursuit (MMP) parameterization. METHOD(S): Visual P300 potentials were recorded in a standard paradigm from a group of healthy subjects and patients in different states of disorder of consciousness. MMP algorithm was used as parametrization, and based upon a subset of recorded data a classifier was trained to distinguish responses to target and non-target stimuli. RESULTS: Cross‑validation performance of the classifier measured as the area under corresponding ROC curves discriminates the healthy group from DoC patients, and in some cases correlates with the severity of DoC. CONCLUSIONS: Replacing estimation of the statistical significance of the average P300 amplitudes by the performance of MMP‑based classification assessed by cross‑validation allows for nonparametric detection of conscious responses in DoC patients, whose ERPs do not always exhibit the classical components. FINANCIAL SUPPORT: This research was supported by the Polish National Science Centre grant 2015/17/B/ ST7/03784.

6

Zastosowanie odpadów poprodukcyjnych do wytwarzania sztywnych pianek poliuretanowych

75%

Kurańska M. , Zieleniewska M. , Auguścik M. , Radwańska J. , Ryszkowska J. , Szczepkowski L. , Prociak A.

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2016

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tom T. 95, nr 2

250--255

PL

Analizowano wpływ odpadów poprodukcyjnych w postaci zmielonych łupin orzecha włoskiego, orzecha laskowego, orzecha ziemnego, nasion truskawek, jak również wytłoków z czarnej porzeczki na właściwości sztywnych pianek poliuretanowych otrzymanych z udziałem bio-poliolu z oleju rzepakowego. Otrzymane materiały poliuretanowe analizowano pod kątem ich zastosowania jako pumeksy kosmetyczne. Wyznaczono m.in. wpływ rodzaju napełniacza na wytrzymałość mechaniczną, kruchość, stabilność wymiarową w podwyższonej temperaturze oraz chłonność wody otrzymanych pianek. Ponadto przeprowadzono analizę struktury komórkowej oraz stabilności termicznej otrzymanych bio-kompozytów.

EN

The ground waste walnut, hazelnut and peanut shells, strawberry seeds and black currant pomace were used as fillers of a polyurethane matrix processed to rigid rapeseed polyol-based composite foams. The foams were studied for mech. strength, brittleness, dimensional stability at elevated temp. In addn., an anal. of cell structure and thermal stability of the resulting materials was carried out. The products were recommended as cosmetic pumices.

7

Brain-computer interfaces and disorders of consciousnes

75%

Durka P. J. , Chabuda A. , Dovgialo M. , Duszyk A. , Pietrzak M. , Rozanski P. , Zieleniewska M.

Acta Neurobiologiae Experimentalis

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2017

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tom 77

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nr Suppl.1

EN

We will start with a brief introduction of the state of the art in EEG-based brain-computer interfaces (BCIs). Similar technologies, that is experimental paradigms and signal processing methods derived from the field of BCI, are believed to be promising candidates to solve one of the major problems of contemporary neuroscience, which is the lack of a stable method for assessment of patients with disorders of consciousness (DoC), commonly (and not quite correctly) addressed as “coma”. This situation motivates the research project started recently in cooperation with a model hospital for children with severe brain damage (Warsaw’s “Alarm Clock Clinic”). In the second part of this talk we will briefly present some of the preliminary results. P300 event-related potential is the classical electroenceph alographic indicator of conscious information processing. It occurs as a component in the EEG trials synchronized to those stimuli, that the subject was paying attention to, e.g. counting. In the standard P300-BCI paradigm, concentration on one of the subsequently flashing stimuli can be used as a conscious choice of one of the options, allowing for non-muscular transfer of information directly from the brain. If reliably detected in a DoC patient in response to the stimulus that the patient was asked to count, it proves the patient’s ability to understand and follow commands. Also, it offers a possibility of establishing a non‑muscular communication channel. A similar reasoning proves the usefulness of detection of the movement imagery reflections in EEG. Finally, brain’s recovery can be also reflected in regaining the sleep pattern known from healthy subjects, also observable in EEG recordings. Detailed presentations of preliminary results from these approaches will be available in the poster session. FINANCIAL SUPPORT: This research was supported by the Polish National Science Centre grant 2015/17/B/ ST7/03784.

8

Classification of time-frequency EEG responses of patients with disorders of consciousness

75%

Chabuda A. , Rozanski P. , Dovgialo M. , Duszyk A. , Pietrzak M. , Zieleniewska M. , Durka P. J.

Acta Neurobiologiae Experimentalis

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2017

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tom 77

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nr Suppl.1

EN

INTRODUCTION: Event-related (de-)synchronization (ER(D)S) is a short‑lasting modulation of specific frequency bands (e.g. alpha band) of EEG, which occurs in response for external stimuli (visual, haptic) or with motor imagery and execution of movements. Since it’s both time- and frequency‑specific, it is typically analysed in time‑frequency space, using Fourier or wavelet methods. AIM(S): As part of the research project of University of Warsaw’s Faculty of Physics and Warsaw’s “Alarm Clock Clinic” (Klinika Budzik), we try to assess whether the presence of a ER(D)S in EEG can be used as an indicator of consciousness in DOC (disorders of consciousness) patients. METHOD(S): Results from two paradigms are presented: 1) motor imagery experiments consisting of a series of auditory commands (“move your hand/leg”) and, 2) haptic stimulation sessions of vibrations applied to patient’s shoulder/hand, while the patient was instructed to focus on stimuli delivered to given location. EEG (23 electrodes from extended 10-20 system) and EMG signals were recorded. EEG data were analysed in time-frequency space to identify whether any statistically significant ER(D)S had occurred. RESULTS: Assessments of possible conscious responses reflected in EEG were correlated with the patients’ CRS‑R (Coma Recovery Scale-Revised) diagnosis and, in case of ER(D)S, with corresponding EMG signal. We present results of several possible indicators, based both on the statistical significance of time‑frequency features, as well as on the cross‑validated classification accuracy. CONCLUSIONS: While the major problem we encountered was caused by severe contamination of EEG with involuntary movement artifacts, we noted that EEG patterns of DOC patients are far from uniform, which is related not only to the patients’ neurological state, but also to physical skull defects and reconstructions. Instead of the classical approach of comparing the patterns of patients to the control group, we propose to look for any statistically stable traces of conscious responses. FINANCIAL SUPPORT: This research was supported by the Polish National Science Centre grant 2015/17/B/ ST7/03784.

9

Biobased polyurethane foams modified with natural fillers

63%

Prociak A. , Kurańska M. , Malewska E. , Szczepkowski L. , Zieleniewska M. , Ryszkowska J. , Ficoń J. , Rząsa A.

Polimery

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2015

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tom T. 60, nr 9

592--599

EN

Two biopolyols have been synthesized from rapeseed oil and applied to obtain rigid and flexible polyurethane foams. Biopolyols were prepared using a two-step method of epoxidation and opening of the oxirane rings. It was found that, regardless of the type of prepared foams, the addition of biopolyols to the polyurethane composition reduces its reactivity, which was confirmed by changes of the dielectric polarization, as well as the reduction of the maximum temperature in the foam core during the foaming process. In the case of the rigid polyurethane polyol, biomodification caused a decrease of the apparent density of the foams, but the foam involving biopolyol had a higher compressive strength. An increase of added ground walnut shells in rigid polyurethane foams also improved their mechanical properties. The introduction of a biopolyol based on rapeseed oil and ultra-fine cellulose to the polyurethane formulation resulted in high resilience flexible foams with improved comfort factor.

PL

Z oleju rzepakowego zsyntetyzowano dwa rodzaje biopolioli, które zastosowano następnie do wytworzenia sztywnych i elastycznych pianek poliuretanowych. Biopoliole otrzymywano dwuetapową metodą epoksydacji i otwarcia pierścieni oksiranowych. Stwierdzono, że — niezależnie od rodzaju pianek — użyty biopoliol wpływa na zmniejszenie reaktywności systemu poliuretanowego, co potwierdzają zmiany polaryzacji dielektrycznej, a także obniżenie maksymalnej temperatury w rdzeniu pianek w trakcie procesu spieniania. W przypadku sztywnych pianek poliuretanowych modyfikacja biopoliolem spowodowała zmniejszenie gęstości pozornej pianek i poprawę ich wytrzymałości na ściskanie. Wprowadzenie napełniacza w postaci zmielonych skorup orzecha do kompozycji pianek sztywnych również poprawiło ich właściwości mechaniczne. Zastosowanie modyfikacji biopoliolem z oleju rzepakowego oraz dodatkiem ultradrobnych cząstek celulozy umożliwiło wytworzenie pianek elastycznych o zwiększonej wartości współczynnika komfortu z zachowaniem dużej odbojności.

10

Bio-poliole z oleju rzepakowego jako surowce do kompozytów naturalnych z napełniaczami naturalnymi dla kosmetyki

63%

Kurańska M. , Michałowski S. , Radwańska J. , Jurecka M. , Zieleniewska M. , Szczepkowski L. , Ryszkowska J. , Prociak A.

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2016

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tom T. 95, nr 2

256--262

PL

Przedstawiono charakterystykę bio-polioli z oleju rzepakowego wytwarzanych w Katedrze Chemii i Technologii Polimerów Politechniki Krakowskiej oraz wpływ wybranych bio-komponentów na właściwości sztywnych pianek poliuretanowych o gęstości pozornej ok. 70 kg/m3. Zbadano wpływ bio-polioli o różnych liczbach hydroksylowych oraz rodzaju i zawartości napełniacza na proces spieniania kompozycji poliuretanowych. Wytworzono i zbadano pianki zawierające bio-poliole oraz napełniacze naturalne w postaci zmielonych łupin orzecha włoskiego lub odpady poprodukcyjne z czarnej porzeczki. Określono wpływ rodzaju i ilości zastosowanych bio-komponentów na właściwości fizykomechaniczne otrzymanych materiałów kompozytowych.

EN

Four polyols were synthesized by epoxidation of rapeseed oil with H2O2 and by oxirane ring opening with diethylene glycol and then used for prodn. of rigid polyurethane biocomposite foams (apparent d. approx. 70 kg/m3) filled with ground walnut shells and post-prodn. pomace from black currant. The effect of bio-polyols and fillers on foaming pressure and temp., dielectric polarization of reaction mixt. and on dimensional stability in air and water, mech. strength and brittleness of the polyurethane foams was studied. The addn. of fillers did not affect the composite foam properties, while the bio-polyol properties played a crucial role.

11

Overnight eeg profiles in monitoring the process of regaining consciousness

63%

Zieleniewska M. , Piotrowski T. , Duszyk A. , Piwonski K. , Chabuda A. , Dovgialo M. , Pietrzak M. , Rozanski P. , Durka P. J.

Acta Neurobiologiae Experimentalis

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2017

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tom 77

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nr Suppl.1

EN

INTRODUCTION: Previous research on disorders of consciousness (DOC) phenomena indicated significant changes in circadian activity and sleep architecture that correlated with patient’s diagnosis. Although polysomnography seems to provide a valuable tool in assessing consciousness level, the main obstacle is the absence of specific staging criteria in scoring sleep patterns of patients with DOC and the inaccuracy of neuropsychological diagnosis. AIM(S): The aim of the study was to identify potential quantitative EEG indices in polysomnographic sleep patterns in patients regaining consciousness with main focus on slow wave activity regulation (SWA) and sleep spindles. Besides visual scoring of PSG recordings, we also performed an automatic SWA and sleep spindles detection and parametrization based on the matching pursuit (MP) algorithm. METHOD(S): Preliminary results of one MCS patient are presented. Overnight multichannel EEG recordings and neuropsychological examination with Coma Recovery Scale-Revised (CRS-R) were performed every 2 months during patient’s one-year stay in a model hospital for children with severe brain damages. Each recording was visually scored by an expert with modified AASM sleep scoring criteria, adjusted to specific characteristics of pediatric DOC sleep patterns. We also performed automatic analysis of EEG sleep profiles based on the MP algorithm. RESULTS: Overall, the overnight EEG profiles of SWA and sleep spindles correlated with visual scores and neuropsychological assessment with CRS-R. Apart from that, for one patient (whose data are hereby presented), some of the SWA and sleep spindles characteristics preceded improvement in the CRS‑R diagnosis. These effects were not clearly detectable in the visual assessment of the polysomnograms. CONCLUSIONS: Preliminary results indicate that automatic parametrization of sleep structures, obtained from the MP algorithm, might provide a valuable tool in monitoring patient’s consciousness level during the rehabilitation process. FINANCIAL SUPPORT: This research was supported by the Polish National Science Centre grant 2015/17/N/ ST7/03769.

12

Semi-rigid polyurethane foams with rapeseed polyol of different viscosity

63%

Ryszkowska J. , Auguścik M. , Zieleniewska M. , Szczepkowski L. , Kurańska M. , Bąk S. , Antos-Bielska M. , Prociak A.

Polimery

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2018

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tom T. 63, nr 1

10--17

EN

The subject of research presented in this article are the semi-rigid polyurethane foams (SRFPUR) produced with a formula developed by the company FAMPUR. It consisted of replacing the petrochemical polyol with two types of rapeseed oil-based polyols of different viscosity. Foams were characterized using such techniques as infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry. With the use of scanning electron microscope changes in the structure of materials were analyzed. In addition, the apparent density, number of closed cells, and properties of materials during compression tests were determined.

PL

Na podstawie receptury opracowanej przez firmę FAMPUR wytworzono półsztywne pianki poliuretanowe (SRFPUR). Poliol petrochemiczny zastąpiono dwoma różniącymi się lepkością typami polioli z oleju rzepakowego. Pianki scharakteryzowano za pomocą spektroskopii w podczerwieni, analizy termograwimetrycznej i różnicowej kalorymetrii skaningowej. Zmiany struktury materiałów badano metodą mikroskopii skaningowej. Oznaczono też gęstość pozorną, liczbę komórek zamkniętych oraz właściwości wytworzonych pianek w próbie ściskania.