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1
PL
Przedstawiono wyniki morfologicznych i strukturalnych badań porowatego azotanu(V) amonu (AN-PP) pochodzącego od wytwórców polskich, rosyjskich, francuskich i chińskich. Badania struktury oraz morfologii przeprowadzono, stosując spektroskopię w podczerwieni (IR), dyfrakcję rentgenowską (XRD) oraz skaningową mikroskopię elektronową (SEM). W wyniku badań SEM zaobserwowano występowanie różnic morfologicznych powierzchni kryształów AN-PP, na które miało wpływ pochodzenie azotanu(V) amonu.
EN
Com. NH₄NO₃ samples of increased porosity (AN-PP) made in Poland, Russia, China and France were studied for morphol. and crystallog. by IR spectroscopy, X-ray diffraction and scanning electron microscopy. Differences in crystal structure between tested AN-PP crystals depended on NH₄NO₃ origin.
EN
Polyurethane elastomers (PUR) based on 2,2,4(2,4,4)-trimethyl-hexamethylenediisocyanate (TMDI) and polyestrodiol (Desmophen D1200) were prepared using various carbohydrates or their derivatives: monosaccharide (glucose), disaccharide (sucrose), sugar alcohol (mannitol and sorbitol). The effect of stoichiometry of ingredients and type of carbohydrates is discussed in relation to their susceptibility to enzymatic degradation catalysed by lipase from Candida antarctica (Novozym 735). The study supports the suitability of carbohydrates or sugar alcohols as important components of PUR for biomedical applications.
PL
Elastomery poliuretanowe (PUR) otrzymano z wykorzystaniem 2,2,4(2,4,4)-trimetyloheksametylenodiizocyjanianu (TMDI), poliestrodiolu (Desmophen D1200) oraz różnych węglowodanów lub ich pochodnych: monosacharydu (glukozy), disacharydu (sacharozy), alkoholi cukrowych (mannitol i sorbitol). Określono wpływ stechiometrii składników i rodzaju węglowodanów na podatność otrzymanych poliuretanów na degradację enzymatyczną katalizowaną lipazą uzyskaną z Candida antarctica (Novozym 735). Potwierdzono możliwość wykorzystania węglowodanów i alkoholi cukrowych jako istotnych składników PUR do zastosowań biomedycznych.
EN
Although many studies have been conducted on the morphological variations and its effects on flotation recoveries of a single mineral system, a systematic study for the flotation behavior of mixtures of minerals has not dwelled much. In this study, th flotation behavior of chromite and serpentine minerals was investigated to distinguish and isolate the contribution of morphology in single and binary systems. For this purpose, the shape analyses for the minerals ground as single and mixture were performed, and their flotation behaviors determined with the micro-flotation experiments. Additionally, the zeta potential measurements were carried out in the presence of sodium oleate as a collector. The shape analysis of the ground samples showed that while the roundness values of chromite and serpentine (gangue) minerals as single were quite different, the particle shape of chromite favored serpentine in the mixture system which in turn suggested that the mineral with the high hardness value dominates the shape characteristics in binary grinding conditions. Accordingly, while the flotation characteristics of chromite in the mixture followed the same trend with the flotation of a single chromite system as a function of particle shape, almost a reverse trend was obtained for the shape and flotation of serpentine in the mixture compared to a single serpentine system. Thus, at roundness values of chromite particles from 0.797 to 0.732, the flotation recoveries of chromite in the mixture increased from 51.0% to 75.4%. On the other hand, likewise chromite, the flotation recoveries of serpentine increased from 20.0% to 37.3% proportional to the roundness range of 0.757 and 0.709. These findings in turn showed that the grinding conditions dictate the soft component to be monitored by the harder and denser component which dominates the angularity and floatability of the mixture.
EN
The purpose of studying the properties of zinc-manganese nanoferrite was to compare organic fuels that were produced in conditions created by the auto gel combustion method, using citric acid, glycine, and urea with different pH values: (citric acid = 6, glycine = 3 and urea = 0). The samples were prepared in stoichiometric ratios to gain Mn0.5Zn0.5Fe2O4, and all the samples were calcined in the same condition (500 °C and 30 minutes). It should be noted that the entire process of synthesis was photographed to analyze the effect of fuels during the combustion process. Combustion reactions were studied by simultaneous thermal analysis (STA), FT-IR spectroscopy, and X-ray diffraction (XRD), also the Rietveld method was used to determine the type and amount of crystalline phases. Magnetic properties of the samples were measured by vibration sample magnetometer (VSM), and their morphology and powder agglomeration was observed by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). Superior magnetic properties of the sample synthesized with glycine were achieved. Urea gave the smallest particle size, while citric acid produced intermediate properties.
EN
This investigation concerns the synthesis as well as structural and morphological characterizations of pure and Ce-doped ZnO nanorods. The samples were synthesized by simple low-temperature hydrothermal process using respectively NaOH and KOH as caustic bases. The as-synthesized nanorods were characterized in terms of their morphological, structural, compositional and vibrational properties. The sizes of the rods were found to be 1.5 μm to 2 μm in length and 250 nm to 300 nm in diameter. The presence of Ce ions in ZnO (NaOH) favored the agglomeration of the rods to form flower-like nanostructures. EDAX measurements showed Zn rich materials with high oxygen vacancy concentration. XRD results indicated that the synthesized ZnO nanorods possess a pure wurtzite structure with good crystallinity. It has also been found that Ce doping deteriorates the crystalline quality of ZnO (NaOH) and improves that of ZnO (KOH). The insignificant intensities observed in FT-IR signals confirm that the synthesized nanorods are of high purity. The Raman spectroscopy studies showed that Ce ions shift the vibrational modes towards lower frequencies. The peaks related to E2 (high) mode in ZnO (KOH) are relatively intense compared to those of ZnO (NaOH). The peaks are found to be shifted and asymmetrically broadened due to anharmonic effects originating from quantum-phonon-effect confinement.
EN
Purpose: This research examined the effects of artificial-aging temperature and time on tensile strength, hardness, microstructure, and fault morphology in AlSiMg. Design/methodology/approach: This research was conducted using aluminium alloy at 120°C, 150°C, and 180°C artificial-aging temperature and 6 hours holding time. The tensile test used ASTM B211-03 standard and hardness test adapted to ALCOA 6061 standard. Findings: Tensile test results indicated the highest tenacity on aluminium alloy at a 150ºC temperature that was 47.263% strain level. In addition to the strain level, this research also obtained the highest tensile strength level at 180ºC that was 62.267 kgf/mm2 and the highest hardness value that was 110 HV. The increase in tensile strength and hardness at 180°C was caused by the increase in Mg, Si, and Al. Based on the microstructure test, the highest tenacity was obtained at 150°C temperature as the result of closed and gathered Mg2Si precipitates; while at 180°C temperature, the precipitates appeared to be more distributed, causing a rise in hardness value and tensile strength. AlSiMg tenacity also exhibited from the number of dimples compared to cleavages at 150°C temperature. Research limitations/implications: The limitation that found in this research was conducted using AlSiMg aluminium Al6061 specimen with an artificial-aging treatment at 120ºC, 150°C, and 180°C temperature for 6 hours and then compared to the raw material. AlSiMg tensile specimen was made according to ASTM E8-E8M standard. Practical implications: This research can be applied in industrial manufacture process to find tensile strength, hardness, microstructure, and fault morphology of Al6061 alloy. Originality/value: According to research result, can be understood that by conducting these experiments, Artificial-aging treatment temperature variations in AlSiMg aluminium alloy could increase hardness.
EN
Cylindrical-electrode-assisted solution blowing spinning (CSBS) is a novel nanofiber preparation method. The electric field of CSBS not only is one of the main innovations of this technology but also plays a key role in the preparation of nanofibers. In this article, the electric field of CSBS and the influences of electric field on the preparation of nanofibers were studied systematically for the first time by simulations, theoretical analyses, and experiments. This paper innovatively established the coaxial capacitor model for studying the CSBS electric field. The effects of electric field on the preparation and morphology of CSBS nanofibers were theoretically investigated by using this model. The theoretical formulas that can express the relationships between the various electric field variables were obtained. The electric field strength distribution, voltage distribution, and the relationships between the electric field parameters of CSBS were obtained by finite element simulations. The simulations’ results show that reducing the diameter of cylinder (DC) or increasing the voltage increase the electric field strength of the jet surface. Experimental results reveal that increasing voltage or reducing DC can reduce the diameter of nanofibers. The experimental and simulation results prove the correctness of the theoretical research conclusions. The theoretical and simulation conclusions of this paper lay a theoretical foundation for further study of CSBS electric field. The experimental conclusions can directly guide the controllable preparation of CSBS nanofibers.
EN
In this study, we demonstrate a facile and cost-effective way to synthesize Nd-Fe-B of various shapes such as powders, rods and fibers using electrospinning, heat-treatment and washing procedures. Initially Nd-Fe-B fibers were fabricated using electrospinning. The as-spun Nd-Fe-B fibers had diameters ranging 489 to 630 nm depending on the PVP concentration in reaction solutions. The different morphologies of the Nd2Fe14B magnetic materials were related to the difference in thickness of the as-spun fibers. The relationships between the as-spun fiber thickness, the final morphology, and magnetic properties were briefly elucidated. The intrinsic coercivity of Nd2Fe14B changed with the change in morphology from powder (3908 Oe) to fiber (4622 Oe). This work demonstrates the effect of the Nd-Fe-B magnetic properties with morphology and can be extended to the experimental design of other magnetic materials.
10
Content available remote Research of 316L metallic powder for use in SLM 3D printing
EN
3D metal printing is an increasingly popular production of steel parts. The most widespread and most accurate method is SLM (Selective Laser Melting), which uses metallic powder as the input material. The article is dedicated to researching the supplied powder from Renishaw. The powder is made by gas atomization and 3 phases of powder (virgin, sift and waste) that are present in the SLM process are examined. Powder morphology by SEM electron microscopy is investigated and the porosity of the powder is measured by optical method. Next, the powder grain size fraction is examined. In conclusion, there are recommendations and other directions of possible research. The main quantitative result from research is that, in general, small particles are reduced in the sift powder and the number of larger particles is increased, but the powder is still usable for further use.
EN
Most of the orthodontic archwires used in the clinical practice nowadays contain nickel (Ni), however, many patients, especially kids, are allergic to Ni. One possible Ni-free alternative is the Titanium-Niobium (Ti-Nb) archwire. Unfortunately, there is not enough information about its mechanical properties in the literature, especially after clinical usage. Therefore, the aim of this work was to investigate and compare the mechanical properties, chemical composition, structure and morphology of as received and used in clinical practice Ti-Nb orthodontic archwires. Materials and methods: We investigated and compared as received and clinically retrieved after 4 and 6 weeks respectively Ti-Nb archwires with dimensions 0.43 × 0.64 mm (0.017 in. × 0.025 in.). The following methods were used: instrumented indentation testing (nanoindentation), X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Results: The nanoindentation investigations of as received and used Ti-Nb archwires revealed a decreasing in their indentation hardness with increased periods of use in the patient’s mouth. Moreover, an increasing of the concentration of Ti in the content of the TiNb alloy was associated with an increased period of use in the oral cavity. The SEM analysis showed changes in surface morphology with increasing the period of use of the archwires. Conclusions: The results showed that there are slight changes in the mechanical and physicochemical properties of the investigated wires after their use in the patient’s mouth. That is why we do not recommend them for recycling.
12
Content available Urban liveability as result of different aspects
EN
Nowadays it is possible to identify a series of parameters that contribute to defining the liveability characteristics of a public space. It is important that all the parameters are satisfied because they are elements that interfere with each other. Morphological characteristics, which partly contribute to defining the environmental performance of the space, together with the functional characteristics of the area, determined by the presence of activities, must be assessed together; however, evaluating them not only in qualitative but also in quantitative terms is not always easy to do. The paper presents a way to evaluate this characteristic of urban space through examples.
EN
The study attempts to identify the main theoretical and methodological positions of morphology. These positions are formulated in the natural sciences (biology) and humanities disciplines (linguistics) and can form the basis for studying the morphology of the city. Morphology has the status of an independent school of science and is a fundamental teaching in biology and linguistics. The choice of the outlined above scientific fields is made due to the similarity of morphological guides. They can be compiled into the description of tasks, the study of the conceptual apparatus, the classification of forms and the processes of mastering which are related to the formation.
PL
W badaniu podjęto próbę określenia podstawowych teoretycznych i metodologicznych stanowisk morfologii sformułowanych w obszarach wiedzy przyrodniczej (biologia) i humanitarnej (językoznawstwo) jakie mogą stanowić podstawę do badania morfologii miasta. W biologii i językoznawstwie morfologia ma status niezależnego kierunku naukowego i podstawowego nauczania. Wybór wyżej wymienionych gałęzi naukowych wynika z podobieństwa ustawień morfologicznych, które można ogólnie podsumować do zadań opisywania, badania aparatu pojęciowego, klasyfikacji form i opanowywania procesów związanych z kształtowaniem.
EN
Five divalent transition metals Cu(II), Co(II), Ni(II), Mn(II) and Zn(II) complexes have been synthesized using 3-hydroxy-4-[N-(2-hydroxynaphthylidene)-amino]-naphthalene-1-sulfonic acid (H3L) Schiff base as a ligand derived from the condensation reaction between 4-amino-3-hydroxynaphthalene-1-sulfonic acid and 2-hydroxy-1-naphthalde-hyde. The synthesized complexes were characterized using microanalytical, conductivity, FTIR, electronic, magnetic, ESR, thermal, and SEM studies. The microanalytical values revealed that the metal-to-ligand stoichiometry is 1:1 with molecular formula [M2+(NaL)(H2O)x].nH2O (where x = 3 for all metal ions except of Zn(II) equal x = 1; n = 4, 10, 7, 4, and 6 for Cu(II), Co(II), Ni(II), Mn(II) and Zn(II), respectively). The molar conductivity result indicates that all these complexes are neutral in nature with non-electrolytic behavior. Dependently on the magnetic, electronic, and ESR spectral data, octahedral geometry is proposed for all the complexes except to zinc(II) complex is tetrahedral. Thermal assignments of the synthesized complexes indicates the coordinated and lattice water molecules are present in the complexes. SEM micrographs of the synthesized complexes have a different surface morphologies. The antimicrobial activity data show that metal complexes are more potent than the parent ligand.
EN
In the present study, the dopant effect of Zn on the crystal structure, thermal properties and morphology of magnesium aluminate (MgAl2O4) spinel (MAS) structure was investigated. A pure and two Zn-containing MASs (e.g. MgAl1.93Zn0.07O and MgAl1.86Zn0.14O) were synthesized for this purpose via a wet chemical method, and the as-prepared samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, differential thermal analysis (DTA), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy techniques. It was found that the crystal structure, thermal properties and morphology of the MAS system change with the increase in the amount of Zn. MgO phase formation was observed. The values of the lattice parameter, unit cell volume and crystallite size increased, and the crystallinity percentage decreased. The morphology was also affected by adding of Zn.
EN
We survey research using neural sequence-to-sequence models as computational models of morphological learning and learnability. We discuss their use in determining the predictability of inflectional exponents, in making predictions about language acquisition and in modeling language change. Finally, we make some proposals for future work in these areas.
EN
Atmospheric pollution by particulate matter has become increasingly important in recent years, because it was found that these airborne particles have various adverse effects on the environment and human health. To extend the knowledge of such pollutants, detailed characterization of sizes, morphology and chemical composition of individual airborne particles is desired. In the presented research, the air microparticles were taken from discarded fiberglass tape filters which are commonly used in MP101M continuous suspended particulate analysers to determine the mass concentration of the particulate matter. These samples, which were collected in Kutna Hora (Czech Republic), were studied using the methods of scanning electron microscopy and energy-dispersive X-ray spectroscopy. Based on microscopic photographs, various geometrical parameters (Feret’s diameter, perimeter, cross-section surface area, circularity, aspect ratio, roundness and solidity) of 237 particles were assessed, while the spectroscopy measurements revealed elemental composition of these particles. Statistical evaluation of the measured data was done using the methods of principal component analysis and compositional data analysis. By these methods, certain relationships among the geometrical parameters and the content of chemical elements in the particles were found. This research also demonstrated that the fiberglass air filters can easily be reused to gain additional information about airborne particles in various places at any time. The character of the particles can also provide information about a possible source of contamination.
PL
Zanieczyszczenie powietrza przez pył zawieszony (PM) staje się w ostatnich latach coraz bardziej znaczące. Stwierdzono, że unoszące się w powietrzu cząsteczki niosą różne niekorzystne skutki dla środowiska i zdrowia ludzkiego. Aby poszerzyć wiedzę na temat takich zanieczyszczeń, pożądana jest szczegółowa charakterystyka rozmiarów, morfologii i składu chemicznego poszczególnych cząstek zawieszonych w powietrzu. W prezentowanych badaniach mikrocząsteczki powietrza zostały pobrane z filtrów taśmowych z włókna szklanego, które są powszechnie stosowane w analizatorach cząstek stałych MP101M. Próbki zostały zebrane w Kutnej Horze (Republika Czeska), były badane metodami skaningowej mikroskopii elektronowej i spektroskopii rentgenowskiej z rozpraszaniem energii. Na podstawie zdjęć mikroskopowych oceniono różne parametry geometryczne (m.in. średnicę Fereta, obwód, powierzchnię przekroju poprzecznego, krągłość, współczynnik kształtu) 237 cząstek, a pomiary spektroskopowe pozwoliły na określenie składu pierwiastkowego tych cząstek. Statystyczną ocenę otrzymanych wyników wykonano metodami analizy głównych składowych i metodami analizy zmiennych złożonych. Stwierdzono istnienie pewnych zależności pomiędzy parametrami geometrycznymi a zawartością pierwiastków chemicznych w cząstkach. Badania te wykazały również, że filtry powietrza z włókna szklanego mogą być z łatwością ponownie wykorzystane do uzyskania dodatkowych informacji o cząstkach zawieszonych w powietrzu w różnych miejscach w dowolnym czasie. Charakter cząsteczek może również dostarczyć informacji o możliwym źródle zanieczyszczeń.
EN
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 characteristicto 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 SO4 2- 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 SO4 2- doped one.
EN
Springs are a vital source of water supply in Quaternary volcanic environments, such as Rinjani Volcano on Lombok Island, and yet little is known about their emergence and recharge areas. Knowledge of spring recharge area can substantially support further spring analysis and management. This study was performed in two spring zones on the southern flank of Rinjani Volcano. It combined the available morphological, lithological, and hydrological datasets to build a conceptual model of the spring recharge areas. According to the analysis results, the conceptual model allowed to describe the flow medium, the aquifer type, and the characteristics of the flow system. The local morphology controlled the direction and gradient of groundwater flow to the springs. The analysis also revealed that the spring water in the study area was meteoric water, which mainly came from rainwater infiltration. Therefore, the boundaries of the spring recharge areas were represented by the morphological divides.
EN
The biodegradable polyurethane/polylactide blend was treated with low temperature hydrogen peroxide plasma, ethylene oxide and immersing in ethanol combined with ultraviolet radiation. The samples sterilized by hydrogen peroxide and ethylene oxide stood practically unaffected, while UV/EtOH caused distinct changes in their mechanical properties. For example the significant reduction of tensile strength occurred, elongation at break became twice lower, while the Young’s modulus increased by 23%. The XPS measurements showed that after all types of treatment atomic carbon and nitrogen concentrations in the surface layer was slightly lower than in the bulk. Instead the surface layer was more enriched with oxygen. Ethylene oxide sterilization caused that both surfaces became more hydrophobic i.e. the contact angle increased about 15% for the top surface and 8% for the bottom surface, respectively. Sterilization with ethanol and UV radiation changed the nature of surface into more hydrophilic, the contact angle of the top surface was reduced about 6% and the bottom about 24%. The FT-IR spectra of all sterilized samples were recorded and discussed. From all used sterilization methods only hydrogen peroxide plasma is fully suitable for biodegradable PU/PLA blend.
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