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has been developed over the years and is still being developed today. The Research Group of Interfacial Phenomena and Flotation was established in the Department, which was at that time headed by doc. Jerzy Szczypa. Then, in 1997 the Department of Interfacial Phenomena was established and currently, because of the reorganization of UMCS it functions as the Department of Interfacial Phenomena at the Institute of Chemical Sciences. Initially, the Group Research was focused on the problems of mineral enrichment using the flotation and foam separation methods. This also involved the research on the wettability of various solids, their surface free energy and methods of its determination, both theoretically and experimentally by measuring contact angles. The research on the electric a double layer and electrokinetic phenomena was also carried out. There were applied also gas chromatography and adsorption methods, as well as modern equipment for examining surface properties of solids and liquids. Over the years, the scope of research on these phenomena has expanded to include superhydrophobic surfaces, the use of plasma for solid surface modification, investigations on layers of biologically active substances on various substrates, and biopolymer films in terms of their biocompatibility and use in pharmacy and medicine. The stability of dispersed systems and emulsions, as well as the influence of external fields (electric and magnetic) on the stability of dispersed systems in terms of the scale deposition were studied. In parallel, extensive research was carried out on the adsorption, aggregation and wetting properties of different surfactants, sugar surfactants, biosurfactants, their multi-component mixtures and those with organic additives such as short-chain alcohols, which being developed. The details of the research and its published results can be found in the extensive bibliography attached to the paper.
konserwację napojów, takich jak mleko, sok, wino lub piwo, akceptację klientów, a także bezpieczeństwo żywności. Bardzo ważny jest wybór odpowiedniego materiału opakowaniowego, ponieważ odgrywa on kluczową rolę w utrzymaniujakości i świeżości produktu w momencie dystrybucji i przechowywania [1, 7]. W artykule przedstawiono szereg nowości literaturowych i rynkowych dotyczących stosowania nowych materiałów do opakowań napojów.
beverages such as milk, juice, wine or beer, customer acceptance, as well as food safety. It is very important to choose the right packaging material because it plays akey role in maintaining the quality and freshness of the product during distribution and storage [1, 7]. The article presents a number of novelties in the literature and market regarding the use of new materials for beverage packaging.
glycol improves the thermodynamics of the solution and increases the hydrophilicity of the membrane. The SEM method confirmed the microporous structure of membranes with an asymmetric structure and various pore sizes and porosities. Higher CA concentration resulted in better tensile properties.
poprawia termodynamikę roztworu i zwiększa hydrofilowość membrany. Metodą SEM potwierdzono m ikroporowatą strukturę membran o asymetrycznej budowie i różnej wielkości porów oraz porowatości. Większe stężenie CA skutkowało lepszymi właściwościami mechanicznymi przy rozciąganiu.
nowadays to avoid food wastage and contamination of the environment. The answer to the mentioned requirements may be found in the innovative approaches such as edible films, biopolymers or the application of additives, allowing longer use of food. Active packagings create a new path of food packaging, concentrated on creation of multi-functional system via formulation of active substances in polymer matrix of polymer packaging. The discussed packaging has a great potential for the application in contact with food due to their positive effect on ecological problems and other unique properties. The aim of the present paper is to discuss the modern solutions in production of biopolymers, employed in production of food packaging and development of more and more functional packaging. In the review, the activities connected with the creation of more ecological and functional, environment-friendly packagings have been submitted and the related barriers have been indicated.
zanieczyszczenia środowiska. Odpowiedzią na te wymagania są innowacyjne podejścia, takie jak: folie jadalne, biopolimery czy zastosowanie dodatków, które pozwolą dłużej korzystać z żywności. Opakowania aktywne to nowa ścieżka pakowania żywności, koncentrująca się na tworzeniu wielofunkcyjnego systemu poprzez formułowanie substancji aktywnych w matrycach polimerowych opakowań. Opakowania takie mają ogromny potencjał do zastosowania w kontakcie z żywnością ze względu na ich pozytywny wpływ na problemy ekologiczne i inne unikalne właściwości. Celem niniejszego artykułu jest przedstawienie nowoczesnych rozwiązań w wytwarzaniu biopolimerów wykorzystywanych do produkcji opakowań do żywności oraz tworzeniu opakowań bardziej funkcjonalnych. W przeglądzie pokazano działania związane z powstawaniem coraz bardziej ekologicznych i funkcjonalnych opakowań przyjaznych dla środowiska oraz wskazano jakie bariery z tym są związane.
traditional packaging materials from non-renewable sources in the coming years.
przez przemysł i oczekuje się, że w kolejnych latach zastąpią tradycyjne materiały opakowaniowe ze źródeł nieodnawialnych.
by a higher onset temperature. The activation energy calculated using imaginary impedance data and Nyquist plots was found to be consistent. Moreover, the dielectric permittivity decreased rapidly with increasing frequency. At high frequencies, there was no dependence of dielectric loss on temperature and frequency. The obtained biopolymer can be used in many applications such as microwave devices, deflection yoke, high-frequency capacitors, sensors, etc.
czym świadczyła wyższa temperatura początku rozkładu. Wykazano zgodność energii aktywacji obliczonej z wykorzystaniem danych dotyczących urojonej impedancji oraz na podstawie wykresów Nyquista. Przenikalność dielektryczna zmniejszała się gwałtownie wraz ze wzrostem częstotliwości. Przy wysokich częstotliwościach nie stwierdzono zależności stratności dielektrycznej od temperatury i częstotliwości. Otrzymany biopolimer można wykorzystać w wielu zastosowaniach, takich jak urządzenia mikrofalowe, jarzmo odchylające, kondensatory wysokiej częstotliwości, czujniki itp.
issues. The erosive impact of the wind can be minimized by enhancing the intactness of the soil surface. There is a prerequisite to adopt viable measures to strengthen soil against wind erosion. There are certain nature-based solutions that can fortify soil against wind erosion and the application of biopolymers is one of them. The objective of this study is to examine the viability of non-toxic biopolymers for stabilizing desert sand by improving its erosion resistance property and strength. In the present experiment, three biopolymers, sodium alginate (SA), pectin (P), and acacia gum (AG), were used with 1, 2, and 3% concentrations for 1 and 0.75 PV as stabilizing agents. The treatment with biopolymers was performed either by surficial treatment (spraying or pouring of solution) or by mixing and compact method based on the viscosity of prepared biopolymer solutions. The biotreated sand samples were tested in a wind tunnel at varying wind speeds of 10, 20, and 30 m/s to assess sand erosion. Surface strengths were assessed by measuring compressive strength using a pocket penetrometer. Crust thickness measurement was performed to check the penetration depth of biopolymer solution and binding of sand particles. All three biopolymers with 1% concentration gave a feasible solution for erosion against wind and binding of particles through SEM analysis. SA and P could not be sprayed for 2 and 3% concentrations due to high viscosity. This solution is also not feasible for the field application. Simultaneously, AG with 2 and 3% concentration was highly soluble, less viscous, and gave more surface strength due to higher percentage of biopolymer concentration.
wodą destylowaną umożliwia usunięcie z substancji ekstrahowanych zanieczyszczeń niehumusowych, w tym rozpuszczalnych w alkoholu amfilowym. W wyniku płukania usuwane są substancje zawierające azot, takie jak białka globularne, aminy, monomery kwasu nukleinowego i retrowirusy. Zmniejszenie zawartości azotu wpływa na zmiany w obliczeniowym składzie elementarnym, a w konsekwencji na charakterystykę kwasów.
dried at 60°C. Elemental anal. of sediments was carried out, and the content of heavy metals and ash was detd. The identification of humic substances was carried out using the FTIR method.
alginate and soy protein isolate. The solutions were poured and dried at 50°C for 24 h. Water content, solubility in water, color and opacity, water vapor permeability and mechanical properties of analyzed films were investigated. The obtained results showed different film properties of which citrus pectin turned out to show the most desired functional properties for instant coffee, including transparency, good sealability and solubility in water.
i cytrusowa, alginian sodu i izolat białka sojowego. Roztwory wylano i suszono w temperaturze 50°C przez 24 h. Zbadano zawartość wody, rozpuszczalność w wodzie, barwę i nieprzezroczystość, przenikalność pary wodnej oraz właściwości mechaniczne analizowanych folii. Uzyskane wyniki wykazały różne parametry folii. Pektyna cytrusowa wykazywała najbardziej pożądane właściwości użytkowe dla kawy rozpuszczalnej, w tym przezroczystość, dobrą zgrzewalność i rozpuszczalność w wodzie.
differential scanning calorimetry (DSC) was used to evaluate the thermal properties. Tensile and flexural mechanical properties as well as Shore hardness were also determined.
właściwości termicznych zastosowano różnicową kalorymetrię skaningową (DSC). Oznaczono również właściwości mechaniczne przy rozciąganiu i zginaniu oraz twardość metodą Shore’a.
also describes the issues of biocompatibility, the principles of sustainable chemistry and sustainable development, as well as market trends and future application directions.
również zagadnienia dotyczące biokompatybilności, zasad zrównoważonej chemii i zrównoważonego rozwoju oraz trendy rynkowe i perspektywiczne kierunki zastosowań.
of gas, liquid, and solid components. This becomes crucial when the chosen research methodology requires the removal of water from samples or their transfer to a cryostat. In the current research, mechanical and topographical examination of cartilage was performed. The materials were generously provided by the Department of Anatomy at the Medical University of Silesia, thereby eliminating any concerns regarding their origin or ethical use for scientific purposes. Our research methodology involved the application of atomic force microscopy (AFM), which minimally disrupts the internal equilibrium among the aforementioned phases. Cartilage, recognized as a ‘universal support material’ in animals, proves to be highly amenable to AFM research, enabling the surface scanning of the examined material. The quantitative results obtained facilitate an assessment of the internal structure and differentiation of cartilage based on its anatomical location (e.g., joints or ears). Direct images acquired during the examination offer insights into the internal structure of cartilage tissue, revealing morphological disparities and variations in intercellular spaces. The scans obtained during the measurements have unveiled substantial distinctions, particularly in the intercellular ‘essence’, characterized by granularities with a diameter of approximately 0.5 μm in ear cartilage and structural elements in articular cartilage measuring about 0.05 μm. Thus, AFM can be a valuable cognitive tool for observing biological samples in the biological sciences, particularly in medicine (e.g. clinical science).
product separated from the widely understood biomass, most usually generated in the pulp and paper industry, falls in line with this trend. In this context, the importance of cellulose, which is used in the production of paper and by-products is greater. Whereas lignin, in the vast majority, i.e. approx. 95-98%, constitutes an energy source generated as a result of its combustion. However, nowadays, due to the huge potential arising from the specific structure of lignin and its properties, attempts are being made at using this material in many different applications within the so-called high added value. Lignin, as a commonly used polymer of unique chemical structure and properties, has recently become a source of many studies utilizing its potential in the preparation of functional materials and/or biomaterials, including hybrid ones. Such systems consist of appropriate inorganic and organic elements, which as a whole constitute a functional product with special properties, not exhibited by individual components. This provides unlimited possibilities in terms of engineering, shaping and practical application in newly developed systems. The huge interest in hybrid materials and/or biomaterials results from their potential applications, namely, in medicine, electronics, optics, electrochemistry, energy storage etc. Therefore, it nowadays becomes justified and important to try and develop new, functional systems, which owing to their specific properties could result in interesting application-wise possibilities in everyday life. Therefore, the attempt to use lignin as a source of many attractive and prospective possibilities is not without significance.
by-products and wastes, which pose a serious threat to the environment as well as to the health and the life of living organisms. There is therefore a need to limit the use of toxic substances at every stage of production, and where this is not possible, appropriate waste management and the development of effective methods of harmful substances removal. In this respect, it seems crucial to introduce the principles of Green Chemistry as widely as possible. Green Chemistry is a concept whose main assumptions focus on designing and conducting chemical processes in a way that minimizes the use and formation of harmful substances as much as possible. This staretgy is based on twelve principles that overlap with the main assumptions of environmental chemistry to improve environmental protection and reduce pollution. There are many techniques and methods that fit into the assumptions of the broadly understood Green Chemistry, the implementation of which allows for sustainable management of post-production waste and by-products as well as their effective disposal. One of such concepts assumes the use of waste substances as a valuable raw material, not only for energy, but above all as a precursor and/or component for the production of innovative materials with high utility potential. Another idea is the use of enzymes, i.e. natural biocatalysts that allow chemical transformations to be carried out under mild process conditions, without the need to use harmful solvents. What's more, enzymes can be used not only at the stage of conversion/synthesis of substrates, but they can also be efficient tools for removing harmful substances. Hence, it seems necessary to undertake attempts aimed at the widest possible management of waste substances, as well as conduct research, the effect of which is the production of functional biocatalytic systems for various applications.
właściwości chitozanu oraz omówiono jego zastosowanie w rolnictwie do otoczkowania nawozów.
galaktoglukomannany, lignina oraz guma gellanowa mogą być stosowane jako substancje wiążące w otoczkowaniu nasion lub jako nośnik substancji aktywnych i mikroorganizmów. Biopolimery zawarte w otoczkach lub zaprawach nasiennych mogą ponadto przyczyniać się do ograniczenia niekorzystnego wpływu środowiska i patogenów na kiełkujące nasiona.
galaktoglucomannans, lignin and gellan gum, can be used as binders in seed coating or carriers of active substances and microorganisms. Moreover, biopolymers contained in the seed coatings and seed dressings can protect germinating seeds from unfavorable influence of environment and pathogens.
prepared from bioresorbable materials with variable surface, geometry, porosity, as well as mechanical and surface properties. They support bone healing and are suitable for tissue regeneration due to their biodegradability and biocompatibility. We believe that materials from biodegradable polymers will play an increasingly important role in future medicine.
polimerów jest związana z możliwością kontrolowania ich właściwości. Zaletą materia-łów polimerowych jest możliwość zmiany powierzchni, geometrii, porowatości, właściwości mechanicz-nych ipowierzchniowych, atakże ich biodegradowalność ibiokompatybilność. Materiały z polimerów biodegradowalnych będą zapewne odgrywać coraz poważniejszą rolę w medycynie przyszłości.
secondary infections it is essential to enhance the antimicrobial (especially antibacterial and antiviral) properties of the materials used in PPE. There are some attempts to modify materials by, for example, silver nanoparticles or zinc oxides. The increasing demand for personal protective equipment, mostly masks, leads to an increase of environmental problem of non-biodegradable wastes. Therefore some researches on use of safer for user’s health sustainable antimicrobial and biodegradable biopolymer fibers, such as cellulose, starch, chitosan, poly(lactic acid) (PLA) or poly(glycolic acid) (PGA), have been done. These biopolymers and their properties are discussed in this article.
(PP). W celu poprawy właściwości przeciwbakteryjnych i przeciwwirusowych stosowanych materiałów, dokonuje się prób modyfikacji ich za pomocą np. nanocząstek srebra lub tlenków cynku. Zwiększenie zapotrzebowania na środki ochrony osobistej, zwłaszcza na maseczki, prowadzi do zwiększenia ilości odpadów, w dużej mierze nie biodegradowalnych. W celu rozwiązania tego problemu oraz poprawy właściwości przeciwbakteryjnych i przeciwwirusowych materiałów z użyciem bezpieczniejszych dla zdrowia użytkowników substancji, prowadzi się badania nad wykorzystaniem włókien z biopolimerów, takich jak celuloza, skrobia, chitozan, poli(kwas mlekowy) (PLA) lub poli(kwas glikolowy) (PGA). Właściwości antybakteryjne i antywirusowe, a także zagadnienia biodegradowalności tych biopolimerów, zostały omówione w niniejszym artykule.
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