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1

Metal-organic frameworks for efficient drug adsorption and delivery

Hyjek Kornelia, Jodłowski Przemysław

Scientiae Radices

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2023

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Vol. 2, Iss. 2

115-189

EN

In recent years, the number of materials used as drug delivery systems (DDS) has increased dramatically. The widespread use of DDSs has improved both the safety and efficacy of therapy. The systems currently in use pose numerous drawbacks and require proper improvements. Although many modern materials are being developed, metal-organic frameworks (MOFs) deserve special attention. Thermal and chemical stability, high specific surface area, low toxicity, high biocompatibility, and great potential for modification are the main features enabling MOFs to be used as DDS. In this review, we describe MOFs, their structure, synthesis, and characterization, as well as drug loading, drug release kinetics, and bioassays. A critical approach is to outline the disadvantages as well as the limitations of MOFs and to identify areas that need to be studied more thoroughly. Nonetheless, the prospective nature of MOFs as DDS and potential adsorbents in overdose or poisoning is presented and highlighted.

2

Ocena termicznego zagrożenia reakcji syntezy związków metaloorganicznych za pomocą kalorymetrii reakcyjnej

Geng Laihong, Li Weiping, Yang Zhigang, Guo Kai, Wang Tao, Wei Jinlong

Przemysł Chemiczny

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2023

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T. 102, nr 7

674--682

PL

Dziesięć reakcji syntezy związków metaloorganicznych oceniono pod kątem zagrożenia termicznego w warunkach adiabatycznych, wykorzystując kalorymetrię reakcyjną. Określono maksymalne temperatury badanych reakcji i adiabatyczny wzrost temperatury. Syntezy chlorku cykloheksylomagnezowego i butylolitu wykazały największe wartości ciepła właściwego i najwyższe maksymalne temperatury osiągnięte po 24 h w warunkach adiabatycznych.

EN

Ten reactions of synthesis of organometallic compds. were assessed by reaction calorimetry for thermal hazard under adiabatic conditions. The max. temps. of the studied reactions and adiabatic temperature rise were detd. The synthesis of cyclohexylmagnesium chloride and BuLi showed the highest sp. heats and highest max. temps. reached after 24 h under adiabatic conditions.

3

Badania nad syntezą i przygotowaniem zielonego dodatku do żywności

Zhao Liang

Przemysł Chemiczny

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2023

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T. 102, nr 8

821--824

PL

Etylomaltol został zsyntetyzowany przez elektrolityczną konwersję α-furanopropanolu do 1,4-dialkoksy-α-furanopropanolu, a następnie zakwaszenie kwasem siarkowym, utlenienie H₂O₂ i hydrolizę. Optymalne parametry procesu były następujące: ładunek 2,5 F/mol, NaBr jako elektrolit, zakwaszanie w temperaturze pokojowej, czas utleniania 150 min i temperatura hydrolizy 100°C.

EN

Etylomaltol was synthesized by electrolytic conversion of α-furanopropanol to 1,4-dialkoxy-α-furanopropanol and subsequent acidification with sulfuric acid, oxidn. with H₂O₂ and hydrolysis. The optimum process parameters were: 2.5 F/mol energization, NaBr as electrolyte, acidification at room temp., oxidn. time 150 min and hydrolysis temp. of 100°C.

4

Removal of silver from chloride solutions using new polymer materials

Pilśniak-Rabiega Magdalena, Wolska Joanna

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 174357

EN

This work presents the synthesis of polymer resins with heterocyclic functional groups, that is, N-(3-aminopropyl)-2-pipecoline, N-(3-aminopropyl)-2-pyrrolidinone, and trans-1,4-diaminocyclohexane for the recovery of Ag(I) from chloride solutions. The modification yield was 69.2, 74.6 and 88.3%, respectively. The best Ag(I) sorption was achieved from synthetic and real chloride solutions in the case of trans-1,4-diaminocyclohexane resin (sorption was 26.8 and 21.5 mg/g, respectively). The sorption kinetic data were well fitted to the pseudo-first-order kinetic model. The maximum sorption capacity of Ag(I) is 105.4, 117.8 and 130.7 mg Ag(I)/g for N-(3-aminopropyl)-2-pipecoline resin, N-(3-aminopropyl)-2-pyrrolidinone resin and trans-1,4-diaminocyclohexane resin, respectively. The trans-1,4-diaminocyclohexane modified resin was very selective towards Ag(I) compared to Cu(II), Pb(II), and Zn(II) from the real chloride leaching solution. The N-(3-aminopropyl)-2-pipecoline and N-(3-aminopropyl)-2-pyrrolidinone resins showed high preferences for Ag(I) over Pb(II) in real solution. These results indicated that the polymers can be applied in the recovery of Ag(I).

5

Synthesis of pneumatic systems in the control of the transport line of rolling elements

Szcześniak Adam, Szcześniak Zbigniew, Cedro Leszek

Acta Mechanica et Automatica

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2023

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Vol. 17, no. 2

254--262

EN

This paper presents the synthesis of a pneumatic control system for a selected configuration of the transport path for the delivery of rolling elements to spiral storage in inter-operational transport. The sequential control system sets the state of the manifolds to ensure a flow of workpieces to serve the subsequent storage. The essential module of the control system is the memory block. It is developed based on a storage filling sequence graph. The filling level of the storages can be monitored in one or two points using sensors. The rolling element displacement control sensors work together with appropriately designed systems to execute the delay of the rising and falling edge input signal. By using a two-level control of the filling level of the storages, it is possible to control the emptying status of the storages as a function of the technological time of removal of the items from the storage between the two control points. Control systems were synthesised and verified using Festo’s FluidSim computer programme.

6

Polimery z pamięcią kształtu i ich otrzymywanie

Andrzejewski Kewin, Czyżów Wiktor, Jacewicz Dagmara, Drzeżdżon Joanna

Wiadomości Chemiczne

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2022

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[Z] 76, 3-4

183--205

EN

SMP (shape-memory polymers) is an innovative class of programmable materials responsive to various stimuli. They are attracting increasing attention regarding possible new inventions, industrial use, and overall polymer research. After a brief introduction, this article examines the conventional shape-memory effect, methods of fabrication of shape memory polymers, and molecular and structural requirements for SMP to function. The shape memory behavior of such polymers is thoroughly presented, with the focus being on the thermo- and photo-induced SME. The uses in biomedical and industrial areas are also discussed.

7

Katalizatory wykorzystywane w syntezie biodiesla

Pobłocki Kacper, Walczak Juliusz, Drzeżdżon Joanna, Jacewicz Dagmara Elżbieta

Wiadomości Chemiczne

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2022

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[Z] 76, 3-4

129--144

EN

Rising prices of electricity, conventional fuels and heating require decisive steps in the further development of technologies based on renewable energy sources. These include geothermal- ; hydrothermal- ; aerothermal- ; and solar energy. Due to the fact that the petrochemical industry is one of the fastest growing branches of the economy, we would like to expand on the topic related to biofuels. Biodiesel is an alternative fuel similar to conventional diesel. It is usually made from animal fat, vegetable oil and waste cooking oil. Its biodegradability, nontoxicity and lack of sulfur and aroma content make it superior to conventional gasoline and diesel. During fuel consumption, it emits fewer air pollutants and greenhouse gases other than nitrogen oxides. In this literature review, we will discuss the latest trends in the world related to catalysts used in biodiesel synthesis.

8

Novel synthesis of PEGylated chitosan. Part II: Research

Wyrębska Łucja, Masłowska-Lipowicz Iwona, Słubik Anna

Technologia i Jakość Wyrobów

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2022

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R. 67

81--89

EN

This article is a continuation of the article: Synthesis and evaluation of the possibility of using some chitosan derivatives in the leather industry. Part I: Literature Review [1]. Part II describes the synthesis of methoxy poly (ethylene glycol) chitosan (mPEGylated chitosan). Methoxy poly(ethylene glycol) with two different molecular weights was used. The effective grafting of poly(ethylene glycol) (PEG) with chitosan was preceded by the activation of the hydroxyl group in the PEG molecule. Benzenesulfonyl chloride was used to activate the hydroxyl group. The course of the reaction for the preparation of PEG esters and PEG-chitosan was confirmed by chromatography.

PL

Praca jest kontynuacją artykułu: Synteza i ocena możliwości wykorzystania niektórych pochodnych chitozanu w przemyśle skórzanym. Część I: Przegląd literatury [1]. W części II opisano syntezę metoksypoli(glikolu etylenowego) chitozanu (mPEGylowanego chitozanu). Stosowano metoksypoli(glikol etylenowy) o dwóch różnych masach cząsteczkowych. Efektywne szczepienie poli(glikolu etylenowego) (PEG) chitozanem poprzedzone było aktywacją grupy hydroksylowej w cząsteczce PEG. Chlorek benzenosulfonylu zastosowano do aktywacji grupy hydroksylowej. Przebieg reakcji otrzymywania estrów PEG i PEG-chitozanu potwierdzono chromatograficznie.

9

Badania nad zwiększeniem skali syntezy TEX

Prasuła Piotr, Szkudlarek Monika, Gołofit Tomasz

Problemy Techniki Uzbrojenia

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2022

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R. 51, z. 160

79--96

PL

Bezpieczeństwo pracy to obecnie najistotniejsze wyzwanie przed którym stoi cały świat. W przemyśle zbrojeniowym główna uwaga skupia się na wytwarzaniu form użytkowych zawierających mało wrażliwe materiały wybuchowe. 4,10-dinitro-2,6,8,12-tetraoksa-4,10-diazaizowurcytan (TEX) jest przykładem mało wrażliwego kruszącego materiału wybuchowego posiadającego dobre parametry detonacyjne oraz niewielką wrażliwość na bodźce mechaniczne. W pracy przedstawiono wykonanie syntezy TEX w zwiększonej skali laboratoryjnej oraz przeprowadzenie badań laboratoryjnych takich, jak pomiar gęstości, spektroskopia Ramana, spektroskopia w podczerwieni oraz analiza termiczna, oznaczenie wrażliwości na tarcie i uderzenie. Przygotowano odlewane mało wrażliwe kompozycje wybuchowe na bazie TEX. Kompozycje te zostały przebadane w laboratorium, wykonano ładunki i przeprowadzono pomiar prędkości detonacji otrzymanych układów.

EN

Work safety is currently the most important challenge facing the whole world. In the arms industry, the main focus is on the production of formulations containing low-sensitive explosives. 4,10-dinitro-2,6,8,12-tetraoxa-4,10 diazoisovurcate (TEX) is an example of a low-sensitive blasting explosive with good detonation parameters and low sensitivity to mechanical stimuli. In this work, the synthesis of TEX was performed on an enlarged laboratory scale, and then laboratory tests were performed, such as density measurement, Raman spectroscopy, infrared spectroscopy and thermal analysis, measurement of sensitivity to friction and impact. Low-sensitive explosive compositions based on TEX were made. These compositions were tested in the laboratory, charges were made and the detonation velocity of the obtained products was measured.

10

Some applications of barium titanate prepared by different methods

Sydorchuk Volodymyr, Khalameida Svitlana, Skwarek Ewa, Biedrzycka Adrianna

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 2

art. no. 147192

EN

The paper presents some application of barium titanate synthesized by different methods. Barium titanate samples were prepared by four procedures: solid state, mechanochemical as direct synthesis and modification as well as hydrothermal and microwave. The obtained samples were systematically studied using X-ray diffraction, nitrogen adsorption, Fourier transform infrared spectroscopy (FTIR), potentiometric titration, and quasi-elastic light scattering and zeta potential measurements. The values of pHpzc (point of zero charge) and pHIEP (isoelectric point) characteristic of the electrical double layer were determined. The prepared samples were tested as photocatalysts under visible light. As a result, relationship between the conditions of barium titanate synthesis, its physicochemical and electrokinetic parameters, as well as photocatalytic activity under visible light was first established.

11

Silver(I) recovery on thiomorpholine - modified functional polymer

Pilśniak-Rabiega Magdalena, Wolska Joanna

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 156609

EN

The functional polymer containing heterocyclic ligands was synthesized by microwave modification of a crosslinked poly(vinylbenzyl chloride–divinylbenzene) matrix with thiomorpholine. The modification yield was 89.3%. The sorbent was used to recover Ag(I) from the synthetic and real chloride solutions. The maximum sorption capacity of Ag(I) was approximately 180 mg Ag/g. The sorption kinetic data were well-fitted to the pseudo-first-order kinetic model. The degree of silver desorption was approximately 50.0% using a 1.0% potassium cyanide solution in a 0.50% hydrogen peroxide solution. The resin retained its capacity toward Ag(I) in five consecutive sorption/desorption cycles. The thiomorpholine modified resin was highly selective toward Ag(I) in relation to Cu(II), Pb(II), Co(II), Ni(II), and Zn(II) from the real chloride leaching solution.

12

Study of synthesis parameters on the physical properties and morphology of smart PNIPAAm hydrogels

dos Santos Luiza Braga Ferreira, de Souza Soares Francielly Moura, Santos Monteiro Emilia, Coimbra Maria Elisa Rodrigues, Elias Carlos Nelson

Materials Science Poland

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2022

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Vol. 40, No. 2

196--205

EN

Bone loss is common in human old age and new materials that promote bone regeneration are an active line of research. In the present work, seven smart hydrogels based on PNIPAAm were synthesized with the prospective to be used in tissue engineering as a scaffold for bone growth. By changing the stoichiometric concentrations of the reagents and the synthesis parameters, hydrogels with different physical properties and morphology were obtained. Swelling, degradation properties, and crystallinity were analyzed. Physical properties were characterized using 1H-NMR, FTIR, and TGA. The results showed that the swelling degree (degree of mass expansion) varied at room temperature from 1,400% for less rigid hydrogels to 550% for stiffer hydrogels. With heating to body temperature, swelling decreases to 300% and 200%, respectively. The samples presented three-dimensional morphology, but they acquired different structures according to the magnetic stirring during the synthesis process. The crosslink and initiator concentrations have an important effect on the polymeric structure and thermal stability of the hydrogels. The PNIPAAm synthesized using 8.9 and 15.7 mol % of MBA are the most promising compounds to be used in the future as a scaffold for biomedical applications due to their high thermal stability, satisfactory 3D surface morphology, and shrinking-swelling property.

13

Catalytic Debenzylation of 2,4,6,8,10,12-Hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo [5.5.0.0.3,1105,9] Dodecane with Pd(OH)2/Al2O)3 in a Batch Suspension Reactor and Optimization of the Reaction Parameters via the Taguchi Method

Bayat Yadollah, Azizkhani Vahid

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 3

231--247

EN

In this paper, the Taguchi method was used for the optimization of the reaction parameters for the synthesis of 2,6,8,12-tetraacetyl-4,10-dibenzyl-2,4,6,8,10,12-hexaazatetracyclo[5,5,0,03,11,05,9]dodecane in the presence of Pd(OH)2/Al2O)3 catalyst in a batch suspension reactor. In order to achieve optimal conditions for this reaction, the experimental studies were conducted under varying reaction parameters, such as temperature, pressure, catalyst to substrate weight ratio, reaction time, and co-catalyst amount. The setting of the reaction parameters was determined in Qualitek-4 (Nutek®) software using the Taguchi experimental design method. Identification of the significant factors and their attributed levels in the Taguchi method were statistically performed via the analysis of variance (ANOVA) technique.

14

Wpływ zeolitu syntetycznego na syntezę tobermorytu

Skawińska Anna, Owsiak Zdzisława

Cement Wapno Beton

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2022

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R. 27, nr 5

320--329

PL

W artykule przedstawiono wyniki badań wpływu dodatku zeolitu syntetycznego na powstawanie tobermorytu w mieszaninie tlenku wapnia z kwarcem. Zeolit syntetyczny otrzymano przez termiczną aktywację haloizytu, a następnie gotowaniu w roztworze wodorotlenku sodu. W pracy badano powstawanie tobermorytu przy stałym stosunku molowym CaO/SiO2 wynoszącym 0,86 w warunkach autoklawizacji odpowiadających ciśnieniu nasyconej pary wodnej w temperaturze 180ºC. Czas syntezy wynosił 4 i 12 godzin. Zeolit syntetyczny dodawany był w ilości 5%, 15% oraz 30% masy suchych składników. Badania wykazały, że zeolit syntetyczny wpływa na powstawania uwodnionych krzemianów wapnia o małym uporządkowaniu struktury. Po 4 godzinach autoklawizacji na dyfraktogramie próbek z dodatkiem zeolitu syntetycznego notuje się niewielki refleks tobermorytu. W próbkach, w których został przekroczony stosunek molowy Al/(Al+Si) > 0.15 pojawiają się hydrogranaty z grupy hibschit-katoit. W pracy wykazano, że hydrogranaty z grupy hibschit-katoit pojawiają się w próbkach z dodatkiem 15% oraz 30% zeolitu po 4 godzinach obróbki hydrotermalnej. Intensywność refleksu katoitu zmniejsza się wraz z wydłużeniem czasu autoklawizacji i zanika dla próbki z 15% zeolitu po 12 godzinach autoklawizacji. Dla tych próbek wykazano również obecność portlandytu.

EN

This paper presents the results of a study of the effect of synthetic zeolite addition on the formation of tobermorite in a burnt lime-quartz mixture. Synthetic zeolite was obtained by thermal activation of halloysite followed by boiling in sodium hydroxide solution. In this study, the formation of tobermorite was investigated at a constant CaO/SiO2 molar ratio of 0.86 under autoclaving conditions corresponding to saturated steam pressure at 180ºC. The synthesis times were 4 and 12 hours. Synthetic zeolite was added at 5%, 15% and 30%. Studies have shown that synthetic zeolite influences the formation of hydrated calcium silicates with poor crystallinity. After 4 hours of autoclaving for samples with synthetic zeolite, a small peak of tobermorite can be found on the XRD pattern. In samples where the molar ratio of Al/(Al+Si) > 0.15 was exceeded, hydrogarnets of the hibschite-katoite group appear. The paper shows that hydrogarnets of the hibschite-katoite group appear for samples with 15% and 30% zeolite after 4 hours of hydrothermal treatment. The intensity of the katoite reflection decreases with increasing autoclaving time and disappears for the sample with 15% zeolite after 12 hours of autoclaving. The presence of portlandite was also demonstrated in these samples.

15

Synteza i zastosowanie aldehydu hydroksypiwalowego

Monasterska Edyta, Siewniak Agnieszka, Pankalla Ewa, Chrobok Anna

Przemysł Chemiczny

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2021

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T. 100, nr 1

62--66

PL

Aldehyd hydroksypiwalowy (HPA) jest półproduktem do wytwarzania wielu cennych związków wykorzystywanych m.in. w przemyśle farb i lakierów, w przemyśle farmaceutycznym oraz w produkcji tworzyw sztucznych jako dodatki podnoszące ich jakość. Na skalę przemysłową HPA otrzymuje się w wyniku kondensacji krzyżowej aldehydu izomasłowego z formaldehydem wobec katalizatorów zasadowych. Przedstawiono metody syntezy HPA ze szczególnym uwzględnieniem stosowanych układów katalitycznych.

EN

A review, with 37 refs., of methods for synthesis and applications of hydroxypivaldehyde.

16

Novel functional polymers for recovery of silver

Pilśniak-Rabiega Magdalena, Wolska Joanna

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 6

36--54

EN

In this study, the functional polymers containing heterocyclic ligands were synthesized by microwave modification of a crosslinked poly(vinylbenzyl chloride–divinylbenzene) matrix with 4-tertbutylpyridine, pyrrolidine, and 3-morpholinopropylamine. The sorbents were used to recover Ag(I) from the synthetic and real chloride solutions (4.00 mol/dm3 of NaCl, 0.100 mol/dm3 of HCl). The best Ag(I) sorption was achieved from synthetic and real chloride solutions in the case of pyrrolidine resin (16.2 and 16.7 mg/g, respectively). The sorption kinetic data were well fitted to the pseudo-first-order kinetic model. The degree of silver desorption was approximately 90% using a 1.0% potassium cyanide solution in a 0.50% hydrogen peroxide solution. All resins showed good selectivity for Ag(I) compared to Cu(II), Pb(II), Co(II), Ni(II), and Zn(II) in real chloride solution. On the basis of this study, it can be concluded that the obtained sorbents can be used to recover Ag from various sources such as ores, wastewater, and jewelry scraps.

17

The use of the linear form of dynamical equations of the satellite attitude control system for its analysis and synthesis

Moldabekov Meirbek, Sukhenko Anna, Shapovalova Darya, Yelubayev Suleimen

Journal of Theoretical and Applied Mechanics

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2021

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Vol. 59 nr 1

109--120

EN

At present, the methods based on using linearized dynamical equations are applied for syn- thesis of an attitude control system of a satellite with nonlinear dynamics. Linearized equa- tions describe the satellite dynamics approximately, which is the main their disadvantage. This article shows that basing on the angular momentum theorem, the nonlinear dynamical equations of the satellite attitude control system can be represented in the form of linear differential equations with variable coefficients, which makes it possible to use engineering methods of stability analysis and analysis of transient quality in the process of synthesis of the satellite attitude control system.

18

An Overview of the Methods of Synthesis, Realization and Implementation of Orthogonal 3-D Rotation Filters and Possibilities of Further Research and Development

Poczekajło Paweł

International Journal of Electronics and Telecommunications

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2021

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Vol. 67, No. 2

295--300

EN

In the paper, an overview of the methods and algorithms of synthesis, realization and implementation used by the author to obtain orthogonal 3-D filters with a structure made of Givens rotations has been presented. The main advantage of orthogonal filters, which may have a lower sensitivity to quantization of the coefficients, was indicated. The author proposed a number of possible changes and modifications of individual stages, which may result in obtaining filters with even better parameters. The work will be the basis for the direction of further research.

19

The Complexity of Synthesis of b-Bounded Petri Nets

Tredup Ronny

Fundamenta Informaticae

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2021

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Vol. 183, nr 1-2

125--167

EN

For a fixed type of Petri nets τ, τ-SYNTHESIS is the task of finding for a given transition system A a Petri net N of type τ(τ-net, for short) whose reachability graph is isomorphic to A if there is one. The decision version of this search problem is called τ-SOLVABILITY. If an input A allows a positive decision, then it is called τ-solvable and a sought net N τ-solves A. As a well known fact, A is τ-solvable if and only if it has the so-called τ-event state separation property (τ-ESSP, for short) and the τ-state separation property (τ-SSP, for short). The question whether A has the τ-ESSP or the τ-SSP defines also decision problems. In this paper, for all b ∈ ℕ, we completely characterize the computational complexity of τ-SOLVABILITY, τ-ESSP and τ-SSP for the types of pure b-bounded Place/Transition-nets, the b-bounded Place/Transitionnets and their corresponding ℤb+1-extensions.

20

Tin-free bioelastomeric polyurethanes for medical applications

Niedźwiedź Malwina, Demirci Gokhan, Kantor-Malujdy Nina, Sobolewski Peter, El Fray Mirosława

Engineering of Biomaterials

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2021

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Vol. 24, no. 163

55