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1

Morphological variability of otolith organs in three congeneric Pagellus species

Bostanci Derya, Yedier Serdar, Türker Dilek, Işmen Ali

Oceanological and Hydrobiological Studies

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2024

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Vol. 53, No. 1

88--101

EN

Morphological features of sagittal otoliths in Pagellus acarne, P. bogaraveo, and P. erythrinus samples collected from the Aegean Sea were used to assess the variability both between Pagellus species and between otolith pairs employing scanning electron microscopy (SEM) and contour shape analysis. Twenty-one otolith morphological characters were compared in detail using SEM analysis. Twelve of these characters differ between Pagellus species and are suitable for distinguishing between the three congeneric Pagellus species. Wavelet functions of otolith contour shape were compared for six Pagellus groups. The wavelet functions obtained from the contour shape analysis showed high variability in the antero-dorsal, postero-dorsal, and antero-ventral regions of otoliths among the six groups analyzed. The results of principal component analysis (PCA) of the wavelet data provided a clear distinction between the groups under study. Cluster analysis supported the PCA results and basically divided them into two main branches. One of these branches contained only P. erythrinus, while P. acarne and P. bogaraveo were present in the other branch. This is the first study to provide detailed morphological characters and wavelet analysis of left- and right-side otoliths in these three congeneric Pagellus species from the Aegean Sea.

2

Experimental investigation of stereolithography and digital light processing additive manufactured pallets

Bairapudi Anil, Sastry C. Chandrasekhara, Krishnaiah J., Sundeep Dola, Eswaramoorthy K. V.

Materials Science Poland

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2024

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Vol. 42, No. 1

1--31

EN

Pallets are a tertiary form of packaging used for stacking, storing, protecting, or transporting goods in supply chains. They are utilized as a base for the unitization of goods for logistics and warehousing. Moreover, pallets can be manufactured using wood, plastic, metal, and corrugated paper, which can be used as material-handling equipment. With several products being transported worldwide and with year-on-year growth, it would be beneficial to make lightweight pallets. Such pallets are recyclable, easy to clean, cheap, and durable to maintain and store. Though most of the pallets are widely available for basic purposes, applications involving high-end bio-packings and transportation of special chemicals require specialized pallets to be manufactured like polymers to ensure a negligible chemical reaction, light in weight, and attenuation in freight capacity, thereby widespread reduction in wastage. With advancements, job to job and immediate requirements, additive manufacturing has the potential to close the gap for jobs with short lead times. If the design process of new pallets has limits the creation of specific codes, the transitions will be smoother in rapid prototyping. This work describes the development of polymer pallets by taking advantage of stereolithography (SLA) and digital light processing (DLP) technology for 3D printing pallets in correlation to injection moulding. After the pallets are designed and manufactured, AM technologies can be applied to specified standards, and the pallets then undergo tensile strength, elongation, and hardness tests. The analysis was carried out for configurable geometries adapting to fork lifting, conveyor, racking, and stacking conditions. Analytical and numerical solutions were carried out to understand the stress and deflections for each geometry and its wide range of applications for pallets.

3

Pogórze Przemyskie Landscape Park Complex as a Habitat for Rare and New to Poland Pinnularia Species

Noga Teresa, Skubisz Jolanta, Poradowska Anita

Journal of Ecological Engineering

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2024

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Vol. 25, nr 2

203--214

EN

The peat bog areas in southeastern Poland are a habitat for many interesting, often endangered, and rare or even new diatom species for Poland. Research conducted in the years 2022–2023 in three landscape parks (Pogórze Przemyskie Landscape Park, Południoworoztoczański Landscape Park, and Janowskie Forests Landscape Park) has allowed the identification of numerous rare and endangered species from the Pinnularia genus, including some that are new to Poland. The paper provides a detailed morphological and ecological characterization of six rare or endangered Pinnularia species, among which two were found to be new for Poland (Pinnularia lokana and P. esoxiformangusta).

4

Enhanced wear and corrosion performance of stainless steel 316L with addition of different weight percentages of GNP

Veeramallu Kalyanamanohar, Krishna Alluru Gopala

Composites Theory and Practice

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2024

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R. 24, nr 1

25--32

EN

The present study reports on the significant improvement in the wear and corrosion resistance of SS316L by adding Graphene nanoplatelets (GNP) of varying wt.% (0.25, 0.5, and 0.75), composites which were prepared by the pressureless sintering technique. The GNP addition can significantly improve the wear and corrosion resistance of SS316L. The wear and corrosion rates for the 0.5 wt.% GNP composite were reduced by 43% and 98%, respectively. The corrosion morphology showed that pitting corrosion was reduced by reinforcing 316L with 0.5 wt.% GNP. Moreover, the intergranular sites were more vulnerable to the corrosion medium when GNP was used at 0.75 wt.%. The worn surface morphology revealed that the tribofilm reduces the coefficient of friction and wear rate due to the lubricating nature of GNP. The presence of GNP was confirmed by Raman spectroscopy in terms of the tribofilm.

5

Synergistic toughening and strengthening of an epoxy resin modified by simultaneous use of two different modifiers

Białkowska Anita, Suroń Patryk, Kucharczyk Wojciech, Hanulikova Barbora, Bakar Mohamed

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 3

art. no. e149176

EN

The present work investigates the effect of modifying an epoxy resin using two different modifiers. The mechanical and thermal properties were evaluated as a function of modifier type and content. The structure and morphology were also analyzed and related to the measured properties. Polyurethane (PUR) was used as a liquid modifier, while Cloisite Na+ and Nanomer I.28E are solid nanoparticles. Impact strength (IS) of hybrid nanocomposites based on 3.5 wt% PUR and 2 wt% Cloisite or 3.5 wt% PUR and 1 wt% Nanomer was maximally increased by 55% and 30%, respectively, as compared to the virgin epoxy matrix, exceeding that of the two epoxy/nanoparticle binaries but not that of the epoxy/PUR binary. Furthermore, a maximum increase in IS of approximately 20% as compared to the pristine matrix was obtained with the hybrid epoxy nanocomposite containing 0.5 wt% Cloisite and 1 wt% Nanomer, including a synergistic effect, due most likely to specific interactions between the nanoparticles and the epoxy matrix. The addition of polyurethane and nanoclays increased the thermal stability of epoxy composites significantly. However, DSC results showed that the addition of flexible polyurethane chains decreased the glass transition temperatures, while the softening point and the service temperature range of epoxy nanocomposites containing nanofillers were increased. FTIR analysis confirmed the occurrence of interaction between the epoxy matrix and added modifiers. All SEM micrographs showed significant roughness of the fracture surfaces with the formation of elongated platelets, explaining the increase in mechanical properties of the epoxy matrix.

6

Możliwość wykorzystania technik mikroskopowych do oceny przebiegu procesu koagulacji

Turlej Tymoteusz

Przemysł Chemiczny

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2023

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T. 102, nr 11

1228--1231

PL

Przedstawiono wyniki badań dotyczących możliwości wykorzystania technik mikroskopowych do oceny przebiegu procesu koagulacji. Zaproponowano wykorzystanie zautomatyzowanego analizatora wielkości i kształtu ziaren Morphologi 4. Próbki zawiesiny rzecznej zostały poddane analizie, zarówno bez, jak i z dodatkiem koagulantu PAX 16. Przeprowadzono pomiary mikroskopowe za pomocą komórki wet-cell dla obu próbek. Ocena przebiegu procesu koagulacji została przeprowadzona przez porównanie obrazów zawiesiny bez i z dodatkiem koagulantu. Porównanie tych obrazów pozwoliło na ocenę skuteczności procesu koagulacji i zrozumienie wpływu koagulantu na morfologię cząstek. Wyniki tego badania mogą mieć zastosowanie w optymalizacji procesów koagulacji oraz w ocenie jakości wody w różnych zastosowaniach, takich jak uzdatnianie wody pitnej i oczyszczanie ścieków.

EN

Suspended river water samples were coagulated with PAX 16 and then morphol. analyzed using wet-cell microscopic measurements. The effectiveness of the coagulation process was evaluated by comparing images of the suspension without and with the addn. of coagulant. This method can be successfully used to evaluate the optimization of the coagulation process and the selection of coagulant dose.

7

Pickering emulsion polymerization of styrene towards alfa-functionalized polystyrene latex: parameters and process conditions

Tercki Dariusz, Orlińska Beata, Słotwińska Dominika, Sajdak Marcin

Polimery

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2023

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Vol. 68, nr 4

206--214

EN

Polymerization conditions in the Pickering emulsion of colloidal silica-stabilized polystyrene latex were optimized. The influence of process conditions on various parameters, including particle size and distribution was investigated. Monomodal particles distribution was obtained by conducting the process at a temperature of 80°C in a slightly acidic environment (pH = 5), while maintaining fast monomer conversion. It has been shown that the amount of stabilizer used in the polymerization process affects the rate of polymerization, therefore the temperature of the process should be adjusted to the amount of colloidal silica used in the process.

PL

Zoptymalizowano warunki polimeryzacji w emulsji Pickeringa lateksów polistyrenowych stabilizowanych krzemionką koloidalną. Zbadano wpływ warunków procesu na m.in wielkość i rozkład cząstek. Monomodalny rozkład cząstek uzyskano prowadząc proces w temperaturze 80°C w środowisku lekko kwaśnym (pH = 5), przy zachowaniu szybkiej konwersji monomeru. Wykazano, że ilość stabilizatora użytego w procesie polimeryzacji wpływa na szybkość polimeryzacji, dlatego też temperatura procesu powinna być dostosowana do ilości używanej w procesie krzemionki koloidalnej.

8

Morphological asymmetry in two marine fish species Acanthopagrus arabicus (Family: Sparidae) and Planiliza klunzingeri (Family: Mugilidae), collected from brackish and freshwater environments in southern Iraq

Jawad Laith A., Al-Saboonchi Azhar A., Musa Zainab J., Nazal Azhar M., Al-Dirawi Ahmed M. H.

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 2

228--239

EN

Morphological asymmetry was analysed in two marine fish species Acanthopagrus arabicus and Planiliza klunzingeri,in brackish and freshwater habitats in southern Iraq. For bothspecies, specimens from the Shatt al-Arab River and Shatt al-Basrah Canal exhibited greater asymmetry values for snout length. In both locations examined, the levels of asymmetry of the physical traits increased as the fish grew. The high levels of asymmetry in the two fish species may be linked to heavy metal pollutants in the two aquatic environments studied.

9

Investigation of additive manufactured micro-lattice structures for defence applications

Shaik Ameer Malik, Reddy Bobbili Veera Siva, Sastry C. Chandrasekhara, Krishnaiah J., Ramakrishna B.

Materials Science Poland

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2023

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Vol. 41, No. 2

383--400

EN

This study investigates the blast mitigation capabilities of A286 steel micro-lattice structures produced through additive manufacturing. The research explores the effects of different manufacturing conditions, such as stress relief and heat treatment, on the mechanical properties and blast resistance of honeycomb and gyroid lattice structures in correlation with armour steel structures. Comprehensive evaluations, including surface morphology, corrosion resistance, and compressive residual stress analysis, reveal notable findings for micro-lattice structures. Micro-lattice structures demonstrated 57.23% higher corrosion resistance compared to conventional materials, presently available in the form of rolled homogeneous armour, medium hardness armour, and high-nitrogen steel. Additionally, honeycomb lattice structures exhibit compressive residual stresses of up to 581.90 MPa, providing significant advantages in blast mitigation potential. These results underscore the significance of lattice geometry, material microstructure, and residual stress in enhancing blast resistance. The research offers valuable insights into optimizing additive manufactured structures as an alternative modular solution for defence applications.

10

Comparative Anatomical and Morphological Study of Three Populations of Salvia aethiopis L. Growing in the Southern Balkhash Region

Nurmahanova Akmaral, Ibisheva Nazerke, Kurbatova Natalia, Atabayeva Saule, Seilkhan Ainur, Tynybekov Bekzat, Abidkulova Karimi, Childibaeva Assel, Akhmetova Aigul, Sadyrova Gulbanu

Journal of Ecological Engineering

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2023

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Vol. 24, nr 9

27--38

EN

The manuscript presents the results of morpho-anatomical structure of vegetative organs of Salvia aethiopis L. S. aethiopis L. is a promising medicinal plant of flora of Kazakhstan, which is able to grow under certain soil and climatic conditions. According to its anatomical and morphological features, S. aethiopis L. is a drought-resistant plant that does not tolerate excess moisture. The aim of the study was to investigate the morpho-anatomical structure of S.aethiopis L. plants growing in three different populations of the South Balkhash region of the country. As a result of the study of the morpho-anatomical structure of vegetative organs of the studied plants, the following features of xeromorphic structure of S.aethiopis L. were noted: strong pubescence of all above-ground parts of plants by simple, globular and glandular hairs, well expressed cuticle with small spinules, presence of cuticular thickening of guard cells, large number of stomatal apparatus on lower epidermis. A comparative analysis of the structure of plants of three different populations showed that in the stem of plants of population № 1 the primary cortex and the diameter of the central cylinder are more pronounced in comparison with plants growing in populations № 2 and № 3, which is due to the growing conditions of these populations. In plants of population № 1, an increase in the thickness of the leaf blade as well as inclusions of essential oils, which are localized in single or paired essential oil passages, were noted. In plants of populations № 1 and № 2, the more essential oil passages were observed. The studied plants of population № 1 have the most pronounced thickness of the primary bark than plants of populations № 2 and № 3. The revealed changes in the morpho-anatomical structure of plants are associated with the influence of various environmental and anthropogenic factors depending on the location of the studied plants.

11

Study of Si morphology in AlSi21CuNiMg cast alloy using col our and deep etching

Tillová Eva, Chalupová Mária, Kuchariková Lenka, Bonek Mirosław, Uhríčik Milan, Pastierovičová Lucia

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 2

art. no. e144618

EN

The effect of possible modification and refining effect of Al-Cu-P-based pre-alloy combined with Fe on the microstructure and the silicon morphology change in hypereutectic Al-Si cast alloy was studied. The samples in the as-cast state were observed by optical and scanning electron microscopy with energy-dispersive X-ray spectroscopy. The 3D morphology of both primary and eutectic silicon was observed by using colour and deep etching in detail. The results showed that the AlCu19P1.4 pre-alloy (1.07 wt.%) combined with the addition of Fe (0.02 wt.%) has a significant effect on the change of the amount, size and morphology of primary Si. This is significantly refined and changes the shape from a coarse irregular star-shaped, polyhedral, or plate-like shape to a fine polyhedral shape. The average size of the primary Si is reduced by about of 78 % from 135 μm to 28 μm and the number of primary Si particles increased from 7.4 to 237. No change in the morphology of the eutectic Si was observed; a refinement of the structure from a coarse needle/plate-like to a fine plate-like structure was seen. The depth etching method using HCl was very effective in the study of the 3D silicon morphology observed, which could be observed in detail without the presence of artefacts.

12

Mechanical properties and Mullins effect in rubber reinforced by montmorillonite

Białkowska Anita, Przybyłek Małgorzata, Sola-Wdowska Marta, Masař Milan, Bakar Mohamed

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 5

art. no. e147059

EN

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.

13

Flammability and morphology of Agel leaf fibre- epoxy composite modified with carbon powder for fishing boat applications

Kurniasih P., Wirawan W. A., Narto A., Pribadi O. S., Imron N. A., Rachman N. F., Pradipta A.

Archives of Materials Science and Engineering

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2023

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Vol. 122, nr 1

13--21

EN

Purpose: Fibre Reinforced Polymer Composites have been extensively developed to construct fishing vessels. This study reports on the successful development of the Agel Leaf Fibre (ALF)- Epoxy composite reinforced with carbon powder and fabricated using the Vacuum Infusion method. Design/methodology/approach: The composites were prepared by varying the carbon powder filler content at volumes of 0%, 10%, and 30%. The fire resistance of the composites was investigated using a burning test according to ASTM D-3014 standards. The morphology of the composites was observed through SEM analysis and analysed using ImageJ software. Findings: The research findings reveal that adding 30% carbon powder in the HCP composite reduced the burning rate by 42.624 mm/sec and the time to ignition by 17.33 seconds, indicating improved fire resistance properties. The carbon powder inhibited flame propagation and reduced the combustion rate by 0.49%. The SEM examination confirmed that the fibre porosity decreased, resulting in a denser composite with enhanced fibre-matrix adhesion. Therefore, the implementation of fire-resistant composite materials in fishing vessel construction can be realised. Research limitations/implications: The present study primarily examined the immediate effects of carbon powder additions on the morphology of the composites. However, it is crucial to consider these composites’ long-term stability and durability. Future research should investigate the ageing behaviour, considering environmental factors such as humidity, temperature, and UV radiation, to assess their impact on the morphology and flammability resistance of the composites. Additionally, it is essential to acknowledge that other factors, including fibre orientation, fibre length, and matrix properties, can significantly influence the overall performance of the composites. Practical implications: The enhanced flammability resistance of Agel Leaf Fibre-Epoxy composites with carbon powder additions holds significant benefits for fishing boat applications. In marine environments, the risk of fire incidents on fishing boats is high, making materials with good fire resistance highly desirable. Therefore, implementing fire-resistant composite materials in fishing boat construction can be realised to reduce the risk of fire incidents in high-seas fishing vessels. Originality/value: Composites with added carbon powder exhibited smaller flames, slower burning rates, and a lack of significant flame propagation. This suggests that adding carbon powder acts as an oxygen barrier and reduces the availability of fuel within the composite.

14

Wykorzystanie geometrii fraktalnej do opisu składu granulometrycznego i morfologii materiałów drobnouziarnionych

Banaś Marian, Hilger Bartłomiej

Przemysł Chemiczny

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2022

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T. 101, nr 11

1019--1022

PL

Geometria fraktalna jest użytecznym narzędziem wykorzystywanym w wielu dziedzinach nauki i techniki, m.in. w analizie obrazów, analizie danych finansowych, i medycynie. Stosuje się ją również do opisu morfologii fazy stałej, materiałów drobnouziarnionych, które mogą pochodzić z różnych procesów, a przez to charakteryzować się najróżniejszymi kształtami. Celem pracy jest przedstawienie sposobów opisu morfologii materiałów drobnouziarnionych za pomocą geometrii fraktalnej. W pracy zawarto informacje na temat stosowanych rozmiarów zastępczych dla cząstek fazy stałej, a także współczynników kształtów oraz metod opisywania prędkości opadania cząstek takiej fazy w płynie.

EN

Fractal geometry was used to describe the particle morphology, properties and behaviour (falling rate, permeability) in order to precisely define the particle shape in numerical form (fractal dimension). Information on the equivalent diameters of solid particles, shape factors and methods used to describe the free fall velocity of particles in a fluid were presented. The method of numerical detn. of the fractal dimension using the results of measurements obtained from a laser diffractometer was described.

15

Influence of chemical foaming on the structure and selected properties of glass fiber reinforced PA6

Konczal Natalia, Nowinka Bartosz, Bieliński Marek

Polimery

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2022

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Vol. 67, nr 10

475--482

EN

The effect of the chemical foaming on the structure (SEM) and selected properties of glass fi ber (30, 60 wt%) reinforced polyamide 6 (PA 6) was investigated. Density, tensile properties and Charpy impact strength were determined. Hydrocerol ITP 825 was used as a blowing agent in the amount of 2 wt%. The size of the pores and the foaming degree depended on the distance from the injection point. The smallest pore size (64 μm) was observed for 60 wt% glass fiber reinforced PA6.

PL

Zbadano wpływ procesu spieniania chemicznego na strukturę (SEM) oraz wybrane właściwości poliamidu 6 wzmocnionego włóknem szklanym (30, 60 % mas.). Oznaczono gęstość, właściwości mechaniczne przy rozciąganiu i udarność Charpy’ego. Jako porofor stosowano Hydrocerol ITP 825 w ilości 2% mas. Wielkość porów i stopień spieniania zależały od odległości od punku wtryskiwania. Najmniejszą wielkość porów (64 μm) stwierdzono w przypadku poliamidu zawierającego 60% mas. włókna szklanego.

16

The effect of shape and roughness on flotation and aggregation of quartz particles

Guven Onur

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 154021

EN

A combination of grinding and abrasion processes was applied to control the shape and roughness of quartz particles to investigate their roles in flotation recoveries and aggregation rates at different collector concentrations. The results showed that while the roundness values (Ro) of quartz particles varied in the range of 0.56-0.58 (Ro) at 480 and 1920 sec grinding, the roughness values of particles varied between 3.12-4.02 μm at 60 and 240 min abrasion. The flotation and aggregation tests showed while the flotation recovery increased from 31.3 % to 34.2 % in reverse proportion to their roundness values at 1x10-6 M DAH concentrations, a similar increasing trend from 34.1% to 38.1 % as a function of their roughness value from 3.12 μm to 4.02 μm. On the other hand, in the case of aggregation tests, while the turbidity values decreased from 40.6 NTU to 32.1 NTU at 1x10-6 M DAH concentrations for rounder particles, it was found as 36.2 NTU to 31.8 NTU for rougher ones. The overall results of this study indicated that tuning the morphology of quartz particles may be used to adjust both the flotation and aggregation rate of particles.

17

Idiosyncratic frequency as a measure of derivation vs. inflection

Copot Maria, Mickus Timothee, Bonami Olivier

Journal of Language Modelling

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2022

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Vol. 10, No. 2

193--240

EN

There is ongoing discussion about how to conceptualize the nature of the distinction between inflection and derivation. A common approach relies on qualitative differences in the semantic relationship between inflectionally versus derivationally related words: inflection yields ways to discuss the same concept in different syntactic contexts, while derivation gives rise to words for related concepts. This differential can be expected to manifest in the predictability of word frequency between words that are related derivationally or inflectionally: predicting the token frequency of a word based on information about its base form or about related words should be easier when the two words are in an inflectional relationship, rather than a derivational one. We compare prediction error magnitude for statistical models of token frequency based on distributional and frequency information of inflectionally or derivationally related words in French. The results conform to expectations: it is easier to predict the frequency of a word from properties of an inflectionally related word than from those of a derivationally related word. Prediction error provides a quantitative, continuous method to explore differences between individual processes and differences yielded by employing different predicting information, which in turn can be used to draw conclusions about the nature and manifestation of the inflection–derivation distinction.

18

The Morphological and Physiological Appearance of Two Vegetable Plants Due to Lead Exposure

Lestari Mahayu Woro, Rosyidah Anis

Journal of Ecological Engineering

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2022

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Vol. 23, nr 6

213--222

EN

This research aimed to determine the effect of different concentrations of Lead (Pb) on the morphology of kale and spinach plants. The process involved planting kale and spinach seeds in tubs and transferring them to polybags with planting media in the form of soil and sand at a ratio of 4:1 after strong roots were developed. It is important to note that the media were analyzed to ensure the Pb content in the soil was below the threshold before planting. Pb was later provided 1 week before planting in the form of PbNO3 in the media at a dose of 1 and 2 g/polybag and mixed effectively to ensure even distribution, while the sample used as the control was not given any Pb. The transplanting process was conducted after the plants were 18 days old in the nursery and the initial observations at 9 DAT showed that the kale leaves were darker with a score of 3 than spinach with a score of 1, but the spinach leaves became darker in color with score 3 as the age of the plants increased. Moreover, the kale changed to a lighter color with a score of 2 from the 9th day of observation after transplanting, while spinach requires 15 DAT to become score 2 until the end of the observation. It should be pointed out that both plants showed morphological changes due to the existence of the Pb but their base leaves did not reflect any effect. The kale leaf tip became blunt, while the spinach leaf tip was not affected and both plants were discovered to have longer roots and more root hairs in the control compared to the treatments. Furthermore, the total chlorophyll of spinach in the control was higher than kale but observed to reduce as the concentration of Pb increased in the treatments. The morphology and physiology of spinach and kale plants changed due to the Pb exposure with the spinach was discovered to be more sensitive as indicated by more visible morphological damage to its leaves at the end of the observation. It is possible to use the morphology of spinach and kale to detect Pb-contaminated land.

19

From Descriptive to Accurate Horseshoe Crab Size Variations in Wild Populations

Chan Li Yu, John Akbar, Shahimi Salwa, Meilana Lusita, Lian Chong Ju, Hoe Loh Ing, Ho Wong Chee, Kumaran Jayaraj Vijaya, Pati Siddhartha, Nelson Bryan Raveen

Journal of Ecological Engineering

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2022

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Vol. 23, nr 12

273--284

EN

Horseshoe crabs have survived until Holocene, but their persistence beyond the Anthropocene is challenged by drastic environment changes that entail impoverishments and the resultant unusual growth sizes. Previously, allometry via morphometric ratio was introduced to classify horseshoe crabs into normal-abnormal growth. However, the descriptive size and weight analysis indicated a considerable portion of Tachypleus gigas with normal allometry. This error was caused by the median sorting of values. Therefore, the same data was treated with correlation before generating a linear equation. By being sexual dimorphs, these arthropods actually have gender-specific morphology indicators which could generate a functional allometry. Since the assessed arthropods were mature, the 19 % yield of smaller female T. gigas was possibly due to degradation effects from poor diets or stress. Yet, for this population, an added risk was female-only harvest. Perhaps, close sizing to male counterparts could be perceived a survival strategy by the female T. gigas. More evidence is needed to strengthen this opinion but for now, this assessment method is novel for accurate allometry assessments in the species with sexual dimorphism. Overall, capture fisheries could have negative impacts and when made severe by sex-specific harvest, the unaccounted practices could collapse sustaining populations.

20

Interfacial Structure of Polytrimethylene Terephthalate/Polyethylene Terephthalate Bicomponent Filament

Yang Zhuli, Wang Fumei, Guan Fuwang, Luo Jin, Qiu Yiping, Zhang Chuyang

Fibres & Textiles in Eastern Europe

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2022

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Vol. 30, no. 1 (151)

71--76

EN

The interfacial structure and binding forces of polytrimethylene terephthalate/polyethylene terephthalate filament were investigated through the methods of Carbon-13 nuclear magnetic resonance (13C-NMR), differential scanning calorimeter (DSC), scanning electron microscopy (SEM) and optical microscopy. When two molten polymers met during the spinning process, an interface layer between the PTT and PET components formed and played an important role in binding the two components together. When the blending time was sufficient, an ester-interchange reaction took place with the generation of the copolymer. The PET recrystallisation was observed in the DSC curve under the influence of entangled PTT molecular chains. The morphology of the cross-section and side view proved that the linear boundary line was short and weaker in binding without a chemical bond and molecular diffusion. Side-by-side bi-component fiber and split-type fiber was able to be controllably spun by adjusting the spinning parameters.