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1

Gas permeability of zeolites - description of the phenomenon

Wałowski Grzegorz

Polish Technical Review

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2026

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No. 1

22--25

EN

This article presents gas flow through porous beds, indicating the results of gas permeability measurements related to the total pressure drop. A clear difference in gas permeability was observed with respect to a given flow direction – this creates unlimited possibilities for heat storage and utilization of zeolites in the context of unconventional energy generation. An important premise is the low energy input required for gas flow in the zeolite system.

PL

W niniejszym artykule omówiono przepływ gazu przez złoża porowate, przedstawiając wyniki pomiarów gazoprzepuszczalności w odniesieniu do całkowitego spadku ciśnienia. Zaobserwowano wyraźną różnicę w gazoprzepuszczalności w zależności od kierunku przepływu – stwarza to nieograniczone możliwości w zakresie magazynowania ciepła i wykorzystania zeolitów w kontekście niekonwencjonalnego wytwarzania energii. Ważnym założeniem jest niski nakład energii wymagany do przepływu gazu w układzie zeolitowym.

2

Zastosowanie mezoporowatych adsorbentów w procesie immobilizacji enzymów

Geszke-Moritz Małgorzata, Kamasa Karolina, Moritz Michał

Przemysł Chemiczny

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2025

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T. 104, nr 6

642--645

PL

Przegląd literaturowy dotyczący zastosowania mezoporowatych krzemionek, szkieletów metaloorganicznych oraz struktur organicznych jako nośników enzymów. Układy nośnik-unieruchomiony enzym znalazły zastosowanie w procesach technologicznych (reakcje hydrolizy, transestryfikacji), diagnostyce laboratoryjnej i neutralizacji substancji szkodliwych. Immobilizacja zazwyczaj zmniejsza aktywność enzymów, zwiększając jednocześnie ich stabilność termiczną oraz odporność na czynniki środowiskowe (pH).

EN

A review, with 25 refs., of use of mesoporous silicas, metal-org. framework and covalent org. framework as the enzyme support. The carrierimmobilized enzyme systems used in technol. processes (hydrolysis, transesterification), laboratory diagnostics and toxic substance neutralization were described. Immobilization decreased the enzyme activity and simultaneously increased their thermal stability to environmental factors (pH).

3

Recent achievements and applications of silsesquioxane-based hybrid materials - an overview

Piórecka Kinga, Kurjata Jan, Stańczyk Włodzimierz A.

Polimery

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2025

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Vol. 70, nr 3

151--165

EN

Based on a literature review from the last 3 years, potential applications of hybrid materials based on silsesquoxanes in engineering, catalysis, biomedicine, and drug delivery systems are presented. Methods of synthesis of such materials are also discussed, considering publications from previous years. Silsesquioxanes are characterized by a defined stable three-dimensional structure consisting of an inorganic core (Si-O-Si) and organic substituents. The rigid core and multifunctionality of substituents make silsesquioxanes ideal candidates for use in the synthesis of innovative materials in the areas of chemistry and biomedicine.

PL

Na podstawie przeglądu literaturowego z ostatnich 3 lat przedstawiono potencjalne zastosowania materiałów hybrydowych na bazie silseskwioksanów w inżynierii, katalizie, biomedycynie i systemach podawania leków. Omówiono również metody syntezy tego typu materiałów, biorąc pod uwagę publikacje z wcześniejszych lat. Silseskwioksany charakteryzują się zdefiniowaną stabilną trójwymiarowa strukturą składającą się z nieorganicznego rdzenia (Si-O-Si) oraz organicznych podstawników. Sztywny rdzeń i wielofunkcyjność podstawników czynią silseskwioksany idealnymi kandydatami do stosowania w syntezie innowacyjnych materiałów w obszarach chemii i biomedycyny.

4

Fabrication and microstructural studies of porous non-isocyanate polyurethanes (NIPU) and NIPU/POSS hybrid nanomaterials obtained with the particle leaching method

Stachak Piotr, Korzeniak Paulina, Hebda Edyta, Wroński Sebastian, Tarasiuk Jacek, Ozimek Jan, Pielichowski Krzysztof

Chemical and Process Engineering : New Frontiers

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2025

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Vol. 46, nr 3

art. no. e105

EN

on-isocyanate polyurethanes (NIPUs) were synthesised by reacting trifunctional cyclic carbonate with poly(propylene oxide)-derived diamine and further chemically modified with polyhedral oligomeric silsesquiox- ane (POSS) moieties to obtain NIPU/POSS hybrids. The materials were manufactured in a porous form using sodium bicarbonate in the particle leaching method. FTIR spectra confirmed the creation of urethane groups in the synthesised materials and the incorporation of POSS particles into the NIPU matrix in the reaction between the oxirane rings present in POSS and the used amines. The SEM and computer micro-tomography (—-CT) images obtained confirmed that the use of the selected size of the sodium bicarbonate crystals allowed pores to be obtained with controlled dimensions. The amount of POSS added (5, 10 and 15 wt.%) did not affect the pore size or its shape. Initial submersion studies using Ringer solution to test in vitro biodegradation behaviour show only small fluctuations in pH and conductivity.

5

Od mofów „w pigułce” do pigułek w mofie : przewodnik teoretyczno-praktyczny

Pander Marzena, Skałecka Natalia, Prus Julia, Stani Oliwia, Bury Wojciech

Wiadomości Chemiczne

|

2024

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[Z] 78, 11-12

1697--1729

EN

The design, synthesis, and characterization of novel materials with unique properties represent an important field of modern chemistry. Metal-Organic Frameworks (MOFs) [1], a class of porous coordination polymers, exemplify such innovative materials. Despite their initial discovery less than 30 years ago, the field of MOFs has expanded rapidly, and is represented now by over 100 000 different structures [2]. The precise design of organic and inorganic building blocks (metal nodes and organic linkers), which can be regarded as chemical Lego® bricks, enables the realization of an almost limitless array of structural architectures, limited only by the imagination of a chemist. This versatility offers the potential to create advanced materials with tailored properties for specific applications, which include sorption and separation processes [3], heterogenous catalysis [4], drug delivery [5], sensing [6] or energy storage [7]. The aim of this tutorial review is to explore and highlight key aspects of modern porous materials, with a particular focus on MOFs. Basic definitions and classification of this class of materials are provided, alongside an overview of its dynamic development in recent years. The structural composition of these materials is discussed in relation to the principles of reticular chemistry, including nomenclature and topological representations. The increasing complexity within this field and the evolution of MOFs is addressed through the introduction of their generations. The main part of this paper focuses on Zr-based MOFs, a distinctive group known for their unique stability and structural versatility, as well as the ability to endure various post-synthetic modifications. The broad spectrum of their applications, from controlled drug delivery to highly efficient heterogeneous catalysis, is presented to showcase the main achievements in this area. This review aims to highlight how advancements in MOF research are paving the way for new developments in material science, encouraging readers for further in-depth exploration of this compelling area of modern chemistry.

6

Kowalencyjne szkielety organiczne : otrzymywanie, właściwości, zastosowanie

Makowski Damian, Bajorowicz Beata

Wiadomości Chemiczne

|

2024

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[Z] 78, 3-4

219--241

EN

Covalent organic frameworks (COFs) are a novel and unique crystalline porous organic polymers formed by the reversible condensation of building units containing light elements and linked by strong covalent bonds. Covalent organic frameworks consist of linkers (building units) and chemical bonds formed between two building units. By carefully selecting the appropriate linkers and bonds, it is possible to create covalent organic frameworks with distinct features. This work provides a concise overview of covalent organic frameworks, including their structural, surface, optical, and electronic properties. The preparation strategies most commonly employed for COFs are also presented, along with relevant examples. The potential applications of covalent frameworks in various fields such as: photocatalysis, medicine, gas separation and storage, photovoltaics and sensors are also discussed, highlighting the need for further development of this important class of materials.

7

Research of Hybrid Aluminium Castings with the Use of Porous Cores

Brůna M., Medňanský Martin, Oslanec P.

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 3

18--24

EN

The paper focuses on the research of hybrid aluminium castings produced by overcasting technology. This is an advanced technology for ensuring the lightness of castings by using the principle of overcasting a core with a porous cellular structure produced by foaming. Process parameters in the foaming phase of the material have a great influence on the resulting porous structure. The article focuses on controlling the influence of pressure during the foaming process on the resulting porosity and evaluating by X-ray tomograph and measuring the relative density. Variants using an initial pressure of 0.3 MPa appear to be the most satisfactory. The challenge of this technology is to ensure adequate bonding of the metals at the interface between the porous core and the solidified metal without penetrating the coating layer. For this reason, the surface treatment of foamed cores with various etchants has been proposed to disrupt the oxide layer on their surface. Macrographs of the uncoated sample and samples etched with 0.5% HF and 10% H3PO4 demonstrated the need for core surface treatment to prevent liquid metal penetration. EDX analysis confirmed the presence of AlPO4 at the core/casting interface in the treated sample.

8

Potential of Indirect Regenerative Evaporative Cooling System (M-Cycle) for Electronic Applications

Olbrycht Robert, Kałuża Marcin, Felczak Mariusz, Levchenko Dmytro, Więcek Bogusław

Pomiary Automatyka Robotyka

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2023

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R. 27, nr 3

19--25

EN

The article presents a simple prototype system based on the concept of indirect regenerative evaporative cooling (IREC) thermodynamic cycle for electronics applications. The key problem of selecting porous capillary material is discussed and preliminary experimental results are presented using IR thermography. The presented research is an initial step towards the development of a laboratory-validated, fully operational IREC system for high-power electronics.

PL

W artykule przedstawiono prototypowy układ chłodzenia oparty na koncepcji cyklu termodynamicznego pośredniego regeneracyjnego chłodzenia wyparnego (IREC) do zastosowań w elektronice. Omówiono kluczowy problem doboru porowatego materiału kapilarnego i przedstawiono wstępne wyniki eksperymentów z wykorzystaniem termografii w podczerwieni. Przedstawione badania stanowią wstępny krok w kierunku opracowania zweryfikowanego laboratoryjnie, w pełni funkcjonalnego systemu IREC do odprowadzania ciepła w systemach elektronicznych dużej mocy.

9

The analytical expressions to describe wave propagation and heat release during microwave treatment of porous inhomogeneous plate based on the W.K.B. solution model

Holubets Taras, Terletskiy Rostyslav, Yuzevych Vlodymyr

Advances in Materials Science

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2023

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Vol. 23, nr 1(75)

69--81

EN

In this paper study for wave propagation in non-homogeneous porous plate sample with slowly varyingrefractive indexis presented. It is based on simple symmetricsolution of the wave equation for linearlypolarized electromagnetic wave aligned into the porous plate perpendicularlyto the external surface. Using correct boundary conditions both the transverseelectric (T.E) and transversemagnetic (T.M) modes, named shortly by (T.E.M) mode for electromagnetic wave, are considered. The Wentzel-Kramers-Brillouin (W.K.B.) solutions for symmetric incident irradiation of fixed power generated at the plate surfaceswas obtained. It isdonethe analysis of the reflection and transmission coefficients on the surfaces of plate.

10

Effect of MHD on unsteady oscillatory Couette flow through porous media

Sharma Bhupendra K., Sharma Pawan Kumar, Cauhan Sudhir Kumar

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 1

188--202

EN

This paper describes the effects of a magnetic field on unsteady free convection oscillatory systems. When temperature and species concentration fluctuate with time around a non-zero constant, "Couette flow" across a porous medium occurs. The system of non-linear ODEs that governs the flow is solved analytically using the perturbation approach because the amplitude of fluctuations is very tiny. Mean flow and transient velocity, transient concentration, transient temperature, heat transfer, mean skin friction and phase and amplitude of skin friction. All have approximate solutions. The influence of different parameters on flow characteristics has been specified and discussed.

11

Free vibration analysis of sandwich beam with porous FGM core in thermal environment using mesh-free approach

Hung Tran Quang, Tu Tran Minh, Duc Do Minh

Archive of Mechanical Engineering

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2022

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LXIX, nr 3

471--496

EN

Thermally induced free vibration of sandwich beams with porous functionally graded material core embedded between two isotropic face sheets is investigated in this paper. The core, in which the porosity phase is evenly or unevenly distributed,has mechanical properties varying continuously along with the thickness according to the power-law distribution. Effects of shear deformation on the vibration behavior are taken into account based on both third-order and quasi-3D beam theories. Three typical temperature distributions, which are uniform, linear, and nonlinear temperature rises, are supposed. A mesh-free approach based on point interpolation technique and polynomial basis is utilized to solve the governing equations of motion. Examples for specific cases are given, and their results are compared with predictions available in the literature to validate the approach. Comprehensive studies are carried out to examine the effects of the beam theories, porosity distributions, porosity volume fraction, temperature rises, temperature change, span-to-height ratio, different boundary conditions, layer thickness ratio, volume fraction index on the vibration characteristics of the beam.

12

The characterization of scaffolds based on dialdehyde chitosan/ hyaluronic acid

Grabska-Zielińska Sylwia, Sosik Adrianna, Małkowska Anna, Olewnik-Kruszkowska Ewa, Stein-Brink Kerstin, Kleszczyński Konrad, Kaczmarek-Szczepańska Beata

Engineering of Biomaterials

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2021

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Vol. 24, no. 163

76

13

The stability of poro elastic wave equations in saturated porous media

Xiong Fansheng, Sun Weitao, Liu Jiawei

Acta Geophysica

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2021

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Vol. 69, no. 1

65--75

EN

Poro-elastic wave equations are one of the fundamental problems in seismic wave exploration and applied mathematics. In the past few decades, elastic wave theory and numerical method of porous media have developed rapidly. However, the math ematical stability of such wave equations have not been fully studied, which may lead to numerical divergence in the wave propagation simulation in complex porous media. In this paper, we focus on the stability of the wave equation derived from Tuncay’s model and volume averaging method. By analyzing the stability of the frst-order hyperbolic relaxation system, the mathematical stability of the wave equation is proved for the frst time. Compared with existing poro-elastic wave equations (such as Biot’s theory), the advantage of newly derived equations is that it is not necessary to assume uniform distribution of pores. Such wave equations can spontaneously incorporate complex microscale pore/fracture structures into large-scale media, which is critical for unconventional oil and gas exploration. The process of proof and numerical examples shows that the wave equations are mathematically stable. These results can be applied to numerical simulation of wave feld in reservoirs with pore/fracture networks, which is of great signifcance for unconventional oil and gas exploration.

14

Zeolity jako nośniki leków

Musielak Ewelina, Feliczak-Guzik Agnieszka, Nowak Izabela

Przemysł Chemiczny

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2020

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T. 99, nr 6

949--952

PL

Przedstawiono przegląd literatury dotyczącej zastosowania zeolitów, krzemionkowych materiałów porowatych o uporządkowanej strukturze, w terapii chorób nowotworowych i bakteryjnych, chorobie Alzheimera oraz jako adiuwantów leków przeciwnowotworowych i środków kontrastowych w obrazowaniu metodą rezonansu magnetycznego.

EN

A review, with 60 refs., of structure and phys.-chem. properties of zeolites used in pharmacotherapy. The use of ordered porous silica materials in therapies for cancer and bacterial origin, in Alzheimer’s disease and as cancer adjuvants and contrast agents in magnetic resonance imaging was discussed.

15

Zastosowanie modelu gazu zapylonego do wyznaczania parametrów strukturalnych materiałów porowatych

Tabiś Bolesław, Boroń Dominika

Przemysł Chemiczny

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2020

|

T. 99, nr 6

888--891

PL

Przedstawiono metodę jednoczesnego wyznaczania współczynników dyfuzji Knudsena i efektywnego współczynnika dyfuzji cząsteczkowej gazów w porowatych ciałach stałych. Omówiono sposób wyznaczania parametrów strukturalnych materiałów makroporowatych. Zastosowano do tego celu model gazu zapylonego. Przedstawiono algorytm postępowania, od wskazówek dotyczących sposobu uzyskania danych doświadczalnych, aż do ich interpretacji. Zagadnienie to zilustrowano na przykładzie dwuskładnikowego roztworu gazowego azot-metan, ale zaproponowana metoda ma znaczenie ogólne.

EN

A quant. description of the diffusive mass movement in porous materials with pores diam. above 100 nm was provided. The method for detg. construction parameters characterizing such materials was discussed. The method of simultaneous detn. of effective mol. diffusion coeffs. and Knudsen diffusion coeffs. was developed. The N2-CH4 binary gaseous mixt. was tested using the method.

16

Izobaryczna metoda stacjonarna wyznaczania współczynników dyfuzji w materiałach porowatych

Boroń Dominika

Przemysł Chemiczny

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2020

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T. 99, nr 5

785--788

PL

Przedstawiono podstawy teoretyczne i algorytm postępowania służący do doświadczalnego wyznaczania współczynników dyfuzji w makroporowatych ciałach stałych. Uwzględniono jednoczesną dyfuzję molekularną i dyfuzję Knudsena. Zaproponowano i przetestowano metodę estymacji skorelowanych współczynników dyfuzji. Ten sposób można zastosować do pomiarów prowadzonych w warunkach ustalonych pod ciśnieniem atmosferycznym, z użyciem dwuskładnikowych roztworów gazowych o zróżnicowanym składzie. Zilustrowano go na przykładach dwóch układów dyfuzyjnych różniących się stosunkiem mas cząsteczkowych składników: {H₂, N₂} oraz {CO₂, H₂}.

EN

Fundamentals and an algorithm for exptl. detn. of diffusion coeffs. in macroporous solids under steady state conditions and const. pressure were presented. Two binary gaseous mixts. of in mol. mass-differing compds. (H₂+N₂ and CO₂+H₂) were taken into consideration as examples.

17

MHD free convection-radiation interaction in a porous medium - part II: soret/dufour effects

Vasu B., Gorla Rama Subba Reddy, Murthy P. V. S. N., Prasad V. R., Beg O. A., Siddiqa S.

International Journal of Applied Mechanics and Engineering

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2020

|

Vol. 25, no. 2

157--175

EN

This paper is focused on the study of two dimensional steady magnetohydrodynamics heat and mass transfer by laminar free convection from a radiative horizontal circular cylinder in a non-Darcy porous medium by taking into account of the Soret/Dufour effects. The boundary layer equations, which are parabolic in nature, are normalized into non-similar form and then solved numerically with the well-tested, efficient, implicit, stable Keller–Box finite-difference scheme. Numerical results are obtained for the velocity, temperature and concentration distributions, as well as the local skin friction, Nusselt number and Sherwood number for several values of the parameters, namely the buoyancy ratio parameter, Prandtl number, Forchheimer number, magnetohydrodynamic body force parameter, Soret and Dufour numbers. The dependency of the thermophysical properties has been discussed on the parameters and shown graphically. Increasing the Forchheimer inertial drag parameter reduces velocity but elevates temperature and concentration. Increasing the Soret number and simultaneously reducing the Dufour number greatly boosts the local heat transfer rate at the cylinder surface. A comparative study of the previously published and present results in a limiting sense is made and an excellent agreement is found between the results.

18

Cement paste microporosity analysis: a comparison of different experimental techniques

Bednarska Dalia, Koniorczyk Marcin

Technical Transactions

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2019

|

Vol. 116, iss. 9

71--80

EN

Microstructure defines almost all material physical properties of a substance. Thus, its proper identification is essential for the assessment of material durability. Porous materials constitute the vast majority of those applied in civil engineering. The most important parameters describing a porous structure are the specific surface area, the shape and volume of pores and the pore size distribution. There are several methods which provide such results; however, each of them has some drawbacks. The main purpose of this paper is to compare results obtained by means of various methods commonly applied to the investigation of microstructure. These methods are mercury intrusion porosimetry (MIP), low temperature sorption of nitrogen and thermoporometry (TPM). The experimental research is conducted on aluminium oxide, which is characterised by unimodal pore size distribution and hardened cement paste prepared using portland cement (CEM I 42.5R with water-cement ratio equal to 0.5. The results obtained by the above-mentioned methods are thoroughly described and compared in this paper. Each of the presented approaches has some limitations; therefore, in order to receive a reliable description of porous microstructure, one has to apply at least two different experimental methods.

PL

Wśród materiałów budowlanych przeważającą większość stanowią materiały porowate. Dokładna znajomość mikrostruktury jest kluczowa w ocenie ich wytrzymałości i trwałości. Istnieje wiele metod eksperymentalnych służących do analizy struktur porowatych. W niniejszym opracowaniu porównane zostały następujące techniki: porozymetria rtęciowa (MIP), niskotemperaturowa adsorpcja azotu oraz termoporometria (TPM). Badaniom eksperymentalnym poddano dwa materiały. Pierwszy z nich, tlenek glinu, jest materiałem referencyjnym o unimodalnym rozkładzie porów. Zgodnie z deklaracją producenta dominująca średnica porów wynosi 7.3 nm. Drugim zastosowanym materiałem jest zaczyn cementowy przygotowany na bazie cementu portlandzkiego CEM I 42,5R. Stwardniały zaczyn charakteryzuje się skomplikowanym rozkładem porów. Opisane techniki analizy mikrostruktury są komplementarne. Aby uzyskać wiarygodny opis struktury wewnętrznej materiałów o skomplikowanym rozkładzie porów należy zastosować co najmniej dwie metody badawcze.

19

Method of Formation of Thermophysical Properties of Porous Materials

Koshlak Hanna, Pavlenko Anatoliy

Rocznik Ochrona Środowiska

|

2019

|

Tom 21, cz. 2

1253--1262

EN

The study of the porosity of thermal insulation made of refractory materials is an important task for the power industry, since the thermal conductivity of porous materials depends on the shape and especially the location of the pores. An analytical review of existing technologies shows that research in this area is not enough to simulate the process of heat and mass transfer in porous alumina material. Experimental determination of the characteristics of heat and mass transfer in porous materials during the formation of a porous structure is a pressing scientific problem. This article analyzes the influence of the composition of materials on the formation of pores, as well as the effect of various impurities and temperature on the thermal conductivity of the material.

PL

Porowatość izolacji termicznej wykonanej z materiałów ogniotrwałych jest ważnym zadaniem dla energetyki, ponieważ przewodność cieplna materiałów porowatych zależy od kształtu, a zwłaszcza od lokalizacji porów. Analiza analityczna istniejących technologii pokazuje, że badania w tej dziedzinie nie są wystarczające do symulacji procesu przenoszenia ciepła i masy w porowatym materiale z tlenku glinu. Eksperymentalne określenie charakterystyki transferu ciepła i masy w materiałach porowatych podczas tworzenia struktury porowatej jest palącym problemem naukowym. W artykule przeanalizowano wpływ składu materiałów na powstawanie porów, a także wpływ różnych zanieczyszczeń i temperatury na przewodność cieplną materiału.

20

Porowate materiały poliuretanowe do zastosowań w diagnostyce medycznej

Swinarew Andrzej S., Muskus Maciej, Gabor Jadwiga, Paluch Jarosław, Popczyk Magdalena, Swinarew Beata, Stanula Arkadiusz, Kubik Klaudia K., Okła Hubert, Liszka Barbara

Przemysł Chemiczny

|

2019

|

T. 98, nr 2

251--256

PL

Opracowano proces wytwarzania pianek węglowych (synteza, karbonizacja), a także dokonano ich szerokiej charakterystyki, wykorzystując mikroskopię świetlną, skaningową mikroskopię elektronową SEM, mikrotomografię komputerową μCT, spektroskopię w podczerwieni FT-IR i chromatografię gazową sprzężoną z detektorem mas GC-MS. Wyniki przeprowadzonych badań umożliwiły wyselekcjonowanie pianek o najlepszych właściwościach sorpcyjnych, które mogą znaleźć zastosowanie w diagnostycznych badaniach fazy oddechowej.

EN

Polyurethane (PUR) foams were synthetized from polyols and methylene diphenyl diisocyanate polymers at mass ratios 1:1, 1:3 and 3:1 without any catalyst or in its presence. The porous structure of the PUR foams was detd. by using scanning electron microscopy and high-resolution 3D computed tomog. The PUR foams showed a good sorbability and could be used in the human diagnostic (respiratory phase).