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Number of results: 85
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Abstract

Powdered polyaniline (PANI) was synthesised chemically with different doping anions namely hydrochloric acid, sulphuric acid and para-toluenesulfonic acid (pTSA). Two-step synthetic procedure was utilised at low temperature. The highest reaction efficiency was found for chlorine-doped PANI. Structural characterization with FTIR revealed the vibration bands characteristic to formation of the emeraldine salt. The surface morphology of doped PANIs was studied by SEM images which showed near globular shape and porous structures with different size of the aggregated particles. They were smaller for Cl–- or pTS–-doped PANI while for SO42– the size was markedly larger. The XRD patterns revealed that there are ordered regions especially for pTS– doped PANI, while the highest conductivity value was recorded for Cl– doped one followed by organic pTS– doped and SO42– doped one.

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Authors and Affiliations

S. Golba
M. Popczyk
S. Miga
J. Jurek-Suliga
M. Zubek
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Abstract

Achene macro- and micromorphology and pericarp anatomy are described in four Polish species of Anemone (A. narcissiflora, A. nemorosa, A. ranunculoides, A. sylvestris). Biometric analysis showed that achene size varies greatly in all the studied species and is of limited diagnostic value. Three types of sculpture connected with the character of the indumentum were distinguished. The presence or absence of stomata on the achene style and the character of the hair base differentiated A. nemorosa and A. ranunculoides, which have the same type of pericarp ornamentation. The endocarp (number of layers and outline of its cells) was shown to be useful in the systematics of Anemone

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Authors and Affiliations

Irmina Maciejewska-Rutkowska
Wojciech Antkowiak
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Abstract

The study assessed the effect of cumulative tropospheric ozone on the morphology of an ozone-sensitive (Bel W3) and an ozone-resistant (Bel B) tobacco cultivar, and two petunia cultivars (Mirage, White Cascade). The plants were exposed at two sites differing in tropospheric ozone level for two months during the 2008 growing season. Similar sets of plants were cultivated in control conditions. Morphological parameters of the plants were measured every week during the experiment. The correlation between the recorded results and the cumulative concentrations of tropospheric ozone measured at the two exposure sites was estimated. The ozone-sensitive tobacco cultivar showed increased visible damage after four weeks of the experiment, although ozone was relatively low during the preceding weeks, possibly confirming the cumulative effect of ozone on the plant response. The ozone-resistant tobacco cultivar showed higher mean plant growth and leaf growth than the ozone-sensitive one throughout the experimental period, but at the exposure sites the ozone-sensitive cultivar showed plant growth similar to or higher than the controls, especially at the forest site where ozone concentrations were higher. This suggests a plant defense against reduction of leaf assimilation area (i.e., against leaf necrosis). Petunia cv. Mirage showed lower growth at the control site and had fewer flowers than White Cascade at all sites. White Cascade had more flowers than Mirage in the last week of the experiment at the forest site where tropospheric ozone was higher. Its mean growth was higher at the forest site than at the other exposure site

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Authors and Affiliations

Klaudia Borowiak
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Abstract

The effect of combination grain refinement with AlTi5B1 master (55 ppm) and Sr-modification with AlSr5 master (20, 30, 40, 50 and 60 ppm) on the microstructure, tensile and hardness properties of AlSi7MgTi cast alloy were systematically investigated. Eutectic silicon was studied by optical and scanning electron microscopy after standard (0.5% HF) and deep etching (HCl). Morphology of eutectic Si changes from compact plate-like (as-cast state) to fibbers (after modification). Si-fibbers in samples with 50 and 60 ppm Sr coarsen probably as a result of over-modification. The optimum mechanical properties has the experimental material which was grain refined and modified with 40 ppm of Sr (UTS = 220.6 MPa; ductility = 6.1%, and 82.3 HBW 5/250/15).

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Authors and Affiliations

L. Kuchariková
E. Tillová
M.S. Bonek
M. Chalupová
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Abstract

Presented paper deals with the morphological category of aspect in Cantonese. Given the lack of a morphological category of tense in Cantonese, aspect holds a particular position in this system, as it is the sole morphological means expressing temporal relations. The aim of the paper is to present the functioning of the various aspects of Cantonese, both perfective and imperfective, based on the theoretical framework presented beforehand, which draws on the previous achievements of linguists in this field. The second section presents what specific morphological means are used to express the category of aspect in Cantonese, which is then followed by a brief discussion of the relation between resultative verb compounds and the perfective aspect. The last, and by far the largest section, presents corpus material which exemplifies the use of different aspect markers. The paper is an attempt to respond to the hitherto lack of consensus among Sinologists about the number as well as the types of aspects that occur in Cantonese.
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Authors and Affiliations

Adrian Kędzior
1

  1. Jagiellonian University in Cracow
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Abstract

Despite great technological progress scientists still are not capable of ascertaining how many species are there on Earth. Systematic studies are not only time-consuming, but sometimes also significantly impeded by constraints of available equipment. One of the methods for morphology evaluation, which is gradually more often used for taxonomical research is microcomputed tomography. It’s great spatial resolution and ability to gather volumetric data during single acquisition without sectioning specimen are properties especially useful in evaluation of small invertebrates. Nondestructive nature of micro-CT gives possibility to combine it with other imaging techniques even for single specimen. Moreover, in case of rare organisms studies it allows to collect full structural data without fracturing their bodies. Application of proper staining, exposure parameters or specific sample preparation significantly improves quality of performed studies. The following article presents summary of current trends and possibilities of microtomography in morphology studies of small invertebrates.
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Authors and Affiliations

Teresa Nesteruk
Łukasz Wiśniewski
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Abstract

The elemental composition and morphology of aerobic granules in sequencing batch reactors (GSBRs) treating high-nitrogen digester supernatant was investigated. The investigation particularly focused on the effect of the number of anoxic phases (one vs. two) in the cycle and the dose of external organics loading (450 mg COD/(L·cycle) vs. 540 mg COD/(L·cycle)) on granule characteristics. Granules in all reactors were formed of many single cells of rod and spherical bacteria. Addition of the second anoxic phase in the GSBR cycle resulted in enhanced settling properties of the granules of about 10.6% and at the same time decreased granule diameter of about 19.4%. The study showed that external organics loading was the deciding factor in the elemental composition of biomass. At 540 mg COD/(L·cycle) the granules contained more weight% of C, S and N, suggesting more volatile material in the granule structure. At lower organics loadings granules had the higher diameter of granules which limited the diffusion of oxygen and favored precipitation of mineral compounds in the granule interior. In this biomass higher content of Mg, P and Ca, was observed.

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Authors and Affiliations

Agnieszka Cydzik-Kwiatkowska
Paulina Rusanowska
Katarzyna Głowacka
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Abstract

Monitoring of activated sludge flocs may provide important information for effective operation and control of wastewater treatment. The research objective is to demonstrate methodology for activated sludge image processing aimed to describe morphological characteristics of activated sludge flocs. The proposed software- -based method was presented and verified by analysis of several activated sludge samples. The results show high efficiency of image segmentation and floc recognition of more than 94% floc components. The analysis of a series of 50 pictures gives rapid and reliable results and can be performed in an automatic or semiautomatic mode. Given inherent heterogeneity of activated sludge flocs, multiple and repeated sample images capture (processing of 50 pictures at a time, repeated at least 4 times ) is recommended.

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Authors and Affiliations

Anna Gnida
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Abstract

The paper presents the results of studies on quartzite milling in a ball mill. The milling was conducted in a batch system, for diversified compositions of balls. The milling product was subjected to granulometrical, morphological and strength analyses. On the basis of the developed Reid's theory and using the Austin-Gardner equation, a form of the function circumscribing the specific rate of comminution of selected size fractions was determined. The values of the breakage rate function bi, j for the mill's apparatus conditions were determined. The impact was investigated for a variable number of grinding media contact points on the values of specific rate S and the values of the breakage rate function bi, j. Furthermore, the values of coefficients occurring in the equations circumscribing the specific rate of milling S and breakage parameter bi, j were determined.

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Authors and Affiliations

Tomasz Olejnik
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Abstract

At thermal junctions of aluminium alloy castings and at points where risering proves to be difficult there appear internal or external

shrinkages, which are both functionally and aesthetically inadmissible. Applying the Probat Fluss Mikro 100 agent, which is based on

nano-oxides of aluminium, results in the appearance of a large amount of fine microscopic pores, which compensate for the shrinking of

metal. Experimental tests with gravity die casting of AlSi8Cu3 and AlSi10Mg alloys have confirmed that the effect of the agent can be of

advantage in foundry practice, leading to the production of castings without local concentrations of defects and without the appearance of

shrinkages and macroscopic gas pores. Also, beneficial effect on the mechanical properties of the metal has been observed.

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Authors and Affiliations

J. Roučka
J. Hotař
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Abstract

Selected results of investigations concerning a shallow water part of the coastal zone, covering the surf zone and the swash zone, are presented. The above research has been carried out by means of field measurements, as well as data-driven and theoretical modelling. The investigations have led to development of a mathematical model of wave transformation and run-up on the shore in the Lagrangian system, as well as identification of infragravity waves (edge waves) in the multi-bar morphological beach system and their linkage with rhythmic shoreline forms (cusps). Some empirical relationships have been obtained for the description of number of bars in a bar system and dissipation of wave energy over such morphological structure. The experimental findings are based on field studies carried out at the IBW PAN Coastal Research Station (CRS) in Lubiatowo.

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Authors and Affiliations

J. Kapiński
R. Ostrowski
Z. Pruszak
G. Różyński
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Abstract

In this study, the effect of gas pressure on the shape and size of the AZ91 alloy powder produced by using the gas atomization method was investigated experimentally. Experiments were carried out at 820°C constant temperature in 2-mm nozzle diameter and by applying 4 different gas pressures (0.5, 1.5, 2.5 and 3.5 MPa). Argon gas was used to atomize the melt. Scanning electron microscope (SEM) to determine the shape of produced AZ91 powders, XRD, XRF and SEM-EDX analysis to determine the phases forming in the internal structures of the produced powders and the percentages of these phases and a laser measuring device for powder size analysis were used. Hardness tests were carried out to determine the mechanical properties of the produced powders. The general appearances of AZ91 alloy powders produced had general appearances of ligament, acicular, droplet, flake and spherical shape, but depending on the increase in gas pressure, the shape of the powders is seen to change mostly towards flake and spherical. It is determined that the finest powder was obtained at 820°C with 2 mm nozzle diameter at 3.5 MPa gas pressure and the powders had complex shapes in general.

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Authors and Affiliations

M. Akkaş
T. Çetin
M. Boz
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Abstract

The pollen morphology of many collections of taxa of the tribe Nigelleae from the family Ranunculaceae which occur worldwide is presented in this study. A total of 88 specimens from 21 taxa, some of which were recently proposed, belonging to the genera Komaroffia, Garidella, and Nigella of Nigelleae were examined using light microscopy (LM) and scanning electron microscopy (SEM). In the tribe, the pollen type is mostly trizonocolpate, but in many taxa and specimens, both trizonocolpate and non-trizonocolpate types occur together. The pollen grains are small to medium (25–53.75 μm × 20–55 μm) in size and oblate to prolate in shape. The exine pattern at the mesocolpium in all the taxa investigated is similar: micro-echinate in LM and micro-echinate-punctate in SEM. The colpus membrane in Komaroffia and Nigella is micro-echinate in both LM and SEM. In Garidella, it is micro-echinate in LM but echinate (spinulose) in SEM. In this study, multivariate analyses, principal component analysis (PCA), and unweighted pair group method with arithmetic mean (UPGMA), were used to evaluate relationships between the genera and species within the tribe with respect to pollen morphology. PCA results show three main groups in the tribe: Garidella, Komaroffia, and Nigella. Moreover, the UPGMA tree also chiefly supports generic segregation into the smaller genera. An overall synthesis of the pollen characteristics of the three genera is provided and discussed.

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Authors and Affiliations

Serap Işık
Emel Oybak Dönmez
Zübeyde Uğurlu Aydin
Alİ A. Dönmez
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Abstract

Until recently, Festuca arietina was practically an unknown species in the flora of Eastern Europe. Such a situation can be treated as a consequence of insufficient studying of Festuca valesiaca group species in Eastern Europe and misinterpretation of the volume of some taxa. As a result of a complex study of F arietina populations from the territory of Ukraine (including the material from locus classicus), Belarus and Lithuania, original anatomy, morphology and molecular data were obtained. These data confirmed the taxonomical status of F arietina as a separate species. Eleven morphological and 12 anatomical characters, ITS1-5.8S-ITS2 cluster of nuclear ribosomal genes, as well as the models of secondary structure of ITS1 and ITS2 transcripts were studied in this approach. It was found for the first time that F arietina is hexaploid (6x = 42), which is distinguished from all the other narrow-leaved fescues by specific leaf anatomy as well as in ITS1-5.8S-ITS2 sequences. Molecular data indicating possible hybridogenous origin of F arietina, fall in line with the anatomical-morphological data and explain the tendency toward sclerenchyma strands fusion with formation of a continuous ring in F arietina, as well as E arietina ecological confinement to psammophyte biotopes.

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Authors and Affiliations

I Bednarska
I Kostikov
A Tarieiev
V Stukonis
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Abstract

Berber languages outside Mauritania have a number of different morphological classes of vowel-final and semivowel-final verbs (“final weak verbs”). The situation in Zenaga of Mauritania looks very different. In this article, the Zenaga reflexes of the non- Mauritanian weak verbs are compared by studying all relevant cognates. As a result, it proves possible to establish to what extent the main weak verb classes of non- Mauritanian Berber are reflected in Zenaga, and to what extent certain irregularities can be understood from Zenaga-internal developments.

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Authors and Affiliations

Maarten Kossmann
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Abstract

Usnea aurantiaco-atra is the dominant flora around King George Island, Antarctica, whose specimens exhibited various phenotypes, even for those with the same ITS sequences in both mycobiont and photobiont. A comprehensive analysis of morphological traits of U. aurantiaco-atra including the reproductive structures, growth forms and ornamentation, cross section of the branches, and the substratum was carried out. Four arbitrary groups were identified based on their reproductive characters, but these groups cannot be distinguished from molecular phylogenetic trees based on fungal or algal ITS sequences. Further, the complicated morphological diversity of the thalli with the same ITS haplotypes in both mycobiont and photobiont suggest that some other factors in addition to the symbionts could influence the morphology of lichens. This implies that lichen is indeed a complex-mini-ecosystem rather than a dual symbiotic association of fungus and alga. Also, a lichenous fungi Phacopsis sp. was identified based on its anatomical characters and ITS sequence, which was also responsible for the black burls-like structures on U. aurantiaco-atra.
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Authors and Affiliations

Shunan Cao
Hongyuan Zheng
Yunshu Cao
Chuanpeng Liu
Lingxiang Zhu
Fang Peng
Qiming Zhou
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Abstract

In the morphosyntactic literature, there exist two approaches to the problem of argument structure in English nominal synthetic compounds such as furniture moving or dog training. According to Borer (2012), such synthetic compounds belong to the class of referential nominals and thus lack argument structure. On the other hand, Alexiadou (2017) maintains that the external argument is present in the structure of synthetic compounds due to their ability to co-occur with by-phrases. In this paper, we present an extensive set of corpus data to show that synthetic -ing compounds do project the external argument, which is evidenced by their ability to license not only by-phrases but also agent-oriented adjectives and instrumental phrases. Importantly, the corpus data indicates that certain synthetic -ing compounds display the capacity to occur in aspectual contexts; nominal compounds fall in two classes in that regard.

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Authors and Affiliations

Sebastian Wasak
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Abstract

On the Polish-Czech Odra river section between Chalupki (Poland) and the Olza river mouth there are unique in European scale meanders (km 21.3 - 26.8). In the 20th century the break-up of two meanders caused by floods in 1967 and 1997 occurred. The total length ofmeandering section has become shorter and the hydraulic gradient increased. The sediments eroded and transported by the stream have settled in different zones of the meandering section. In 1997 the inlet to the meander I was blocked by settled sediments causing the break-up of this meander. The paper presents the preliminary estimation ofmorphological changes of the river bed and the physical and rheological characteristics for settled sediments.
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Authors and Affiliations

Robert Głowski
Robert Kasperek
Włodzimierz Parzonka
Mirosław Wiatkowski
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Abstract

In this study the effect of anionic surfactants on the morphology of activated sludge floes and biomass activity is quantitatively described. Three anionic surfactants: sodium dodecyl sulphate, sodium alkylbenzene sulphonate and sodium alkyltrioxyethylene sulphate were tested. The batch experiments were performed for a wide range of initial concentrations of anionics in wastewater from 2.5 to 2500 mgdm3. In spite of different chemical structure the action of all tested anionic surfactants resulted in the decrease of activated sludge floes dimensions at the similar level. It occurred that in the range of anionics concentrations, which are typical for domestic wastewater (2.5-25 mgdm3), they contributed to the decrease of mean projected area of floes by about 30%, whereas at the concentrations of 250 and 2500 mg-dm3 mean projected area decreased usually by 50-60%. Sodium alkylbenzene sulphonate exerted the strongest inhibition effect on dehydrogenase activity of activated sludge biomass. This effect coincided with the decreased degrees of removal for this surfactant and its biodegradation products, especially at its lower initial concentrations in wastewater.
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Authors and Affiliations

Ewa Liwarska--Bizukojc
Marcin Bizukojc
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Abstract

Fumonisins are highly toxic metabolites produced by Fusarium proliferatum and Fusarium verticillioides. Little is known about the effects of a chronic low level of fumonisins on intestinal structure and innervation in monogastric animals, even though the intestine is the first organ exposed to fumonisins. The influence of the most prevalent strains of fumonisins, FB1 and FB2, on intestinal and liver morphology, the enteric nervous system and intestinal epithelial cell prolif- eration was investigated in an experimental rat model of fumonisin intoxication. Adolescent (5-weeks-old), male Wistar rats were randomly divided into a control group (C group) not treated with fumonisins or intoxicated with fumonisins (FB group). FB1 together with FB2 were daily administered intragastrically at a dose of 90 mg/kg body weight for 21 days. The damaging effect was assessed by determination of the activity of ALAT and AspAT. Samples from the small intes- tine and liver were taken and blood samples were collected to determine the activity of gamma-glutamyl transferase (GGT) and amylase. The exposure to FBs resulted in histopathological degenerative alterations in hepatocytes, including mild vacuolar degeneration and ballooning. FB exposure was also toxic in the duodenum and jejunum, where significant changes in morphology, cell proliferation, collagen wall fibres and innervation were observed. Taken together, the results obtained strengthen the hypothesis that chronic exposure to FBs could induce intestinal damage, including damage to the enteric nervous system and may have consequences for general health.

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Authors and Affiliations

H. Rudyk
E. Tomaszewska
M.B. Arciszewski
S. Muszyński
A. Tomczyk-Warunek
P. Dobrowolski
J. Donaldson
O. Brezvyn
I. Kotsyumbas
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Abstract

The present work investigated the properties of rubber vulcanizates containing different nanoparticles (Cloisite 20A and Cloisite Na+) and prepared using different sonication amplitudes. The results showed that a maximum improvement in tensile strength of more than 60% over the reference sample was obtained by the nanocomposites containing 2 wt.% Cloisite 20A and 1 wt.% Cloisite Na+ and mixed with a maximum amplitude of 270 µm. The modulus at 300% elongation increased by approximately 18% and 25% with the addition of 2 wt.% Cloisite 20A and 3 wt.% Cloisite Na+, respectively. The shape retention coefficient of rubber samples was not significantly affected by the mixing amplitude, while the values of the softness measured at the highest amplitude (270 µm) were higher compared to those of mixtures homogenized with lower amplitudes. The loading-unloading and loading-reloading processes showed similar trends for all tested nanocomposites. However, they increased with increasing levels of sample stretching but were not significantly affected by filler content at a given elongation. More energy was dissipated during the loading-unloading process than during the loading-reloading. SEM micrographs of rubber samples before and after cycling loading showed rough, stratified, and elongated morphologies. XRD results showed that elastomeric chains were intercalated in the MMT nanosheets, confirming the improvement of mechanical properties. The difference between the hydrophilic pristine nanoclay (Cloisite Na+) and organomodified MMT (Cloisite 20A) was also highlighted, while the peaks of the stretched rubber samples were smaller, regardless of the rubber composition, due most probably to the decrease of interlayer spacing.
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Authors and Affiliations

Anita Białkowska
1
Małgorzata Przybyłek
1
Marta Sola-Wdowska
1
Milan Masař
2
Mohamed Bakar
1
ORCID: ORCID

  1. University of Technology and Humanities in Radom, Faculty of Chemical Engineering and Commodity Science, Poland
  2. Tomaš Bata University in Zlin, Centre of Polymer Systems, Czech Republic
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Abstract

The aim of this paper is to examine the phenomenon of infixation in the Spanish language. This study has been divided into five parts, with the exception of the introduction. The first one presents ways of classifying various affixes according to their position within words. In the next two parts, two different types of infixation in Spanish are presented. The first of them concerns diminutive forms and has an expressive function in them. The second one appears in vesreisms (Sp. vesreísmos), where it indicates the grammatical gender of nouns and adjectives. The first infixes occur in all varieties of the Spanish language, while the latter are dialectal. In the fourth part, an attempt is made to propose further arguments in favor of recognizing the existence of infixed forms in Spanish. In the last part of the article, some conclusions are drawn on the basis of the examples and observations presented in the previous parts of the study.
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Authors and Affiliations

Piotr Sorbet
1
ORCID: ORCID

  1. Maria Curie-Skłodowska University, Lublin

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