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1
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Application of pyrolysis-capillary gas chromatography with NPD detection in thermal degradation of polyphosphazenes study

100%
Paulsdorf J., Wiemhöfer H.-D., Orinák A., Zámostný P., Bělohlav Z., Baxter D.
Open Chemistry
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2007
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vol. 5
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issue 1
271-290
EN
Polyphosphazenes represent a unique class of polymers with a backbone composed of alternating phosphorous and nitrogen atoms. The thermal behaviour and decomposition of a variety of polyphosphazenes depends on the type of side groups present. Especially those that bear aryloxy side groups, possess a high temperature stability as well as excellent flame resistance. Pyrolysis-capillary gas chromatography has been used in a study of three polyphosphazene samples for thermal stability characterisation. Degradation products were detected with three single detectors for flame ionisation (FID), nitrogen-phosphorous sensitivity (NPD) and mass spectrometry (MSD) at different pyrolysis temperatures ranging from 300°C up to 800°C. The NPD responses for phosphorous or nitrogen fragments of polyphosphazenes have been used for the construction of degradation product schemes and the examination of the thermal stability of the polyphosphazene’s backbone. Partial identification of the degradation products present in the gaseous phase was achieved by MSD. The polyphosphazenes thermal degradation conversion rates were at a maximum at 450–500°C. At various pyrolysis temperatures, the calculated N/P peak area ratio is a function of the degree of polyphosphazene-N=P-chain degradation, and reflective of the nitrogen - phosphorous detector sensitivity. NPD proved to be suitable tool for characterization of polyphospazene thermal stability.
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Degradability of organic-inorganic cellulose acetate butyrate hybrids in sea water

100%
Wojciechowska P., Heimowska A., Foltynowicz Z., Rutkowska M.
Polish Journal of Chemical Technology
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2011
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vol. 13
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issue 2
29-34
EN
Environmental degradability of novel organic-inorganic cellulose acetate butyrate hybrids obtained via solgel process was investigated. The degradation of hybrids was studied under marine exposure conditions in the Baltic Sea for a period of 25 weeks. The influence of characteristic parameters of sea water on the degree of degradation monitored by changes of weight and optical microscopy was discussed. The degraded samples were also examined by FT-IR spectroscopy. It has been established that the CAB/silica hybrids are more susceptible to biodegradation in sea water environment than pure cellulose acetate butyrate.
3
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Corrosion Inhibition of Mild Steel in Nitric Acid Media by some Schiff Bases Derived from Anisalidine

100%
Saxena N., Kumar S., Sharma M. K., Mathur S. P.
Polish Journal of Chemical Technology
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2013
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vol. 15
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issue 1
61-67
EN
Corrosion inhibition performance of mild steel in nitric acid solution containing different concentration of anisalidine derivative Schiff bases viz. N- (4-nitro phenyl) p-anisalidine (SB1), N- (4-chloro phenyl) p-anisalidine (SB2), N- (4-phenyl) p-anisalidine (SB3), N- (4-methoxy phenyl) p-anisalidine (SB4), N- (4-hydroxy phenyl) p-anisalidine (SB5) has been investigated using mass loss, thermometric and potentiostate polarization technique. Inhibition efficiencies of Schiff bases have been evaluated at different acid strength. The inhibition efficiency was found larger than their parent amines. Inhibition efficiencies of synthesized Schiff bases increase with inhibitor concentration. Inhibition efficiency increases up to 98.32% with ansalidine derivative Schiff base.
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Core/Clad Phosphate Glass Fibres Containing Iron and/or Titanium

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Ahmed I., Shaharuddin S. S., Sharmin N., Furniss D., Rudd C.
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issue 1
EN
Phosphate glasses are novel amorphous biomaterials due to their fully resorbable characteristics, with controllable degradation profiles. In this study, phosphate glasses containing titanium and/or iron were identified to exhibit sufficiently matched thermal properties (glass transition temperature, thermal expansion coefficient and viscosity) which enabled successful co-extrusion of glass billets to form a core/clad preform. The cladding composition for the core/clad preforms were also reversed. Fe clad and Ti clad fibres were successfully drawn with an average diameter of between 30~50 μm. The average cladding annular thickness was estimated to be less than 2 μm. Annealed core/clad fibres were degraded in PBS for a period of 27 days. The strength of the Fe clad fibres appeared to increase from 303 ± 73 MPa to 386 ± 45 MPa after nearly 2 weeks in the dissolution medium (phosphate buffered solution) before decreasing by day 27. The strength of the Ti clad fibres revealed an increase from 236 ± 53 MPa to 295 ± 61 MPa when compared at week 3. The tensile modulus measured for both core/clad fibres ranged between 51 GPa to 60 GPa. During the dissolution study, Fe clad fibres showed a peeling mechanism compared to the Ti clad fibres.
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Impact of photocatalysis on carotenoic acid dye-sensitized solar cells

100%
Jöhr R., Zajac L., Günzburger G., Hug H., Such B., Szymonski M., Meyer E., Glatzel T.
Hybrid Materials
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2015
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vol. 2
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issue 1
EN
Sensitized mesoporous titania is of increasing interest for catalysis and photovoltaic devices such as dye-sensitized solar cells (DSCs). For photovoltaic applications, the catalytic properties of TiO2 can cause degradation of the dyes during device fabrication. This is especially the case if natural sensitizers are used. We addressed this issue by fabrication of carotenoic acid sensitized solar cells under inert and ambient assembly conditions. The DSCs were investigated by currentvoltage and quantum efficiency measurements. Further characterization of the cells was made using impedance spectroscopy. The conversion efficiency of the DSCs prepared under inert conditions improved by at least 25% and the devices showed an enhanced reproducibility. The improvement of the DSCs correlated with the conversion efficiency of the sensitizers under inert conditions. We conclude that the photocatalytic bleaching depends on the electron injection efficiency of the sensitizer. Hence carotenoic acids support their own degradation. However, the photocatalytic decomposition of the sensitizers can be avoided by fabrication of the DSCs under inert conditions.
6
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Impact of Land Use Changes and Dynamic Vegetation Changes on Vascular Flora Diversity in Małków–Bartochów (the Warta River Valley)

88%
Woziwoda B., Michalska-Hejduk D.
Acta Universitatis Lodziensis. Folia Biologica et Oecologica
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2011
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vol. 7
125-138
EN
The paper presents the changes of vascular plant flora in the Małków–Bartochów peatland area (the Warta River valley) which took place over a 40-year period. Vanishing, permanent and new components of the flora are presented with a special focus on valuable (protected by the law, threatened and locally rare) species. Changes in the share of ecological groups are estimated and discussed. Anthropogenic and natural factors, directly or indirectly influencing (in the past and at present) flora composition, are noted and analyzed.
7
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Monitoring and remediation technologies of organochlorine pesticides in drainage water

88%
Ismail A., Derbalah A., Shaheen S.
Polish Journal of Chemical Technology
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2015
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vol. 17
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issue 1
115-122
EN
This study was carried out to monitor the presence of organochlorine in drainage water in Kafr-El-Sheikh Governorate, Egypt. Furthermore, to evaluate the efficiencies of different remediation techniques (advanced oxidation processes [AOPs] and bioremediation) for removing the most frequently detected compound (lindane) in drainage water. The results showed the presence of several organochlorine pesticides in all sampling sites. Lindane was detected with high frequency relative to other detected organochlorine in drainage water. Nano photo-Fenton like reagent was the most effective treatment for lindane removal in drainage water. Bioremediation of lindane by effective microorganisms (EMs) removed 100% of the lindane initial concentration. There is no remaining toxicity in lindane contaminated-water after remediation on treated rats relative to control with respect to histopathological changes in liver and kidney. Advanced oxidation processes especially with nanomaterials and bioremediation using effective microorganisms can be regarded as safe and effective remediation technologies of lindane in water.
8
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Rutherford Backscattering Spectroscopy of Mass Transport by Transformation of PbI2into CH3NH3PbI3within np-TiO2

75%
Lang F., Juma A., Somsongkul V., Dittrich T., Arunchaiya M.
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issue 1
EN
Mass transport during transformation of PbI2 infiltrated in nanoporous TiO2 into CH3NH3PbI3 has been investigated by Rutherford backscattering spectroscopy (RBS). Fast initial reaction kinetics were confirmed using optical ex-situ and in-situ measurements. Mapping with energy dispersive X-ray spectroscopy of the cross section of samples revealed a homogeneous PbI2 infiltration in nanoporous TiO2 before transformation but an accumulation of Pb and I at the surface after transformation, in accordance with a depletion of Pb and I in a near surface region. Quantitative depth profiles of Pb and I were obtained from RBS analysis. An instant degradation of CH3NH3PbI3 to PbI2 and volatiles upon ion radiation was found. The concentration profiles of Pb could be simulated with a one dimensional diffusion model taking into account an effective diffusion coefficient of Pb in the nanocomposite (about 1.5 10-11 cm2/s) as well as a parameter considering frazzling at the surface due to formation of crystallites.
9
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The influence of landscape structure on the quality index of surface waters

75%
Fedoniuk T. P., Fedoniuk R. H., Romanchuk L. D., Petruk A. A., Pazych V. M.
Journal of Water and Land Development
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2019
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issue 43
10
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A Review on Strontium Oxide Nanoparticles

75%
Senthilkumar V., Nisha S., Saravanan M.
World News of Natural Sciences
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2023
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vol. 50
147-158
EN
This review article provides a comprehensive overview of the synthesis, characterization, and potential applications of strontium oxide nanoparticles (SrONPs). The focus is on discussing the stability of SrONPs, including their resistance to degradation and corrosion in harsh chemical environments. The review highlights their robust thermal and electrical resistivity, making them suitable for high-temperature applications and maintaining reliable performance in electrical systems. Various characterization techniques, such as UV-Visible spectrometry, FTIR spectroscopy, SEM, XRD, and dynamic light scattering, are utilized to analyze the properties of SrONPs. Additionally, the review explores their potential applications, including their antibacterial properties and suitability for diverse fields such as electronics, energy storage, lighting, and wastewater treatment. This review provides a comprehensive understanding of SrONPs, emphasizing their stability, versatility, and potential for wide-ranging industrial and biomedical applications.
11
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Autofagia, czyli wielkie sprzątanie

63%
Orzechowski A.
Kosmos
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2017
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vol. 66
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issue 2
153-166
PL
Autofagia jest procesem fizjologicznym zachodzącym u eukariontów (rośliny, grzyby i zwierzęta), polegającym na degradacji różnych składników komórki rozpoznanych jako uszkodzone lub zbędne. W zasadzie, każdy proces prowadzący do przekazania materiału komórkowego lizosomom należy uważać za autofiagię. W zjawisku kontrolowanej autodestrukcji lizosomy pełnią rolę komórkowego "zakładu oczyszczania i utylizacji odpadów". W pewnym uproszczeniu można uznać, że autofagia jest dla komórki "sprzątaczką" z umiejętnością recyklingu. Pomimo że o autofagii wiedziano już w latach 60. ubiegłego wieku, rodzaje autofagii (mikro-, makro- i autofagia zależna od białek opiekuńczych) oraz przebieg i mechanizmy sprawcze zostały poznane i szczegółowo opisane dopiero po wprowadzeniu nowych technik biologii molekularnej w czym szczególnie zasłużył się Yoshinori Ohsumi, uhonorowany w roku 2016 Nagrodą Nobla z Fizjologii lub Medycyny. Obecnie wiadomo, że autofagia nadzoruje ważne fizjologiczne funkcje, ale nabiera szczególnego znaczenia w warunkach stresu komórkowego, kiedy dochodzi do uszkodzenia komórki. Taka sytuacja ma miejsce w stanach chorobowych, przy czym wiele obserwacji zebranych od chorych i dane doświadczalne wskazują nieprawidłowo działającą autofagię jako przyczynę choroby.
EN
Autophagy is a physiological process found in eukariotes (plants, fungi, and animals) in which different cellular constituents identified as damaged or obsolete are degraded. In principle, every process of trafficking cell components into the lysosomes should be regarded as autophagy. In the progressive and controlled autodestruction the lysosomes represent waste disposal and recycling centre. Truthfully, autophagy could be considered a "housekeeper" with recycling capability. Alhough autophagy is known from early sixties of the last century, individual forms of autophagy (micro-, makro-, and chaperone-mediated autophagy, CMA) as well as precise course was not described in details unless molecular biology techniques were applied, for which Yoshinori Ohsumi was honoured with Nobel Prize in Physiology or Medicine in 2016. Nowadays, it is widely accepted that autophagy controls important physiological functions where cellular components need to be degraded and recycled, and it is even more important in stress conditions, when cells undergo damage. Such situations come up in diseases, moreover a great deal of observations obtained from sick individuals as well as experimental data confirm abnormal autophagy as a cause of disease.
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Study of the Biodegrability of Degradable/Biodegradable Plastic Material in a Controlled Composting Environment

63%
Vaverková M., Toman F., Adamcová D., Kotovicová J.
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vol. 19
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issue 3
347-358
EN
The objective of this study was to determine the degrability/biodegradability of disposable plastic bags available on the market that are labeled as degradable/biodegradable and those certified as compost. The investigated materials were obtained from chain stores in the Czech Republic and Poland. Seven kinds of bags (commercially available) were used in this study. One of them was a disposable bag made of HDPE and mixed with totally degradable plastic additive (TDPA additive). Another was a disposable made of polyethylene with the addition of pro-oxidant additive (d2w additive). One was labeled as 100% degradable within various periods of time, from three months up to three years, and four were certified as compostable. The test was carried out in a controlled composting environment. The biodisintegration degree of the obtained pieces was evaluated following a modified version of ČSN EN 14806 Norm "Packaging - Preliminary evaluation of the disintegration of the packaging materials under simulated composting conditions in a laboratory scale test" and a modified version of ČSN EN ISO 20200 "Plastics - Determination of the degree of disintegration of plastic materials under simulated composting conditions in laboratory-scale test" (ISO 20200:2004). The emphasis was put on determination whether the bags are degradable/biodegradable or not.
PL
Celem badań było określenie degradacji/biodegradacji "jednorazowych" plastikowych toreb dostępnych na rynku, które są oznaczone jako degradowalne/biodegradowalne, jak również toreb certyfikowanych jako nadające się do kompostowania. Badane materiały są dostępne w sieci sklepów w Czechach oraz w Polsce. Badaniu poddano siedem próbek. Jedną z nich była jednorazowa torba wykonana z folii HDPE (polietylenu łatwo degradowalnego) z dodatkiem TDPA (powodującego całkowitą degradację folii polietylenowej). Badano też torby wykonane z różnymi dodatkami, co powodowało ich rozkład w określonym czasie. Testy zostały przeprowadzone w kontrolowanych warunkach kompostowania. Stopień rozkładu określono za pomocą zmodyfikowanej wersji normy ČSN EN 14806 "Opakowania - Ocena wstępna rozpadu materiałów opakowaniowych w symulowanych warunkach kompostowania w badaniach w skali laboratoryjnej" oraz zmodyfikowanej wersji normy ČSN EN ISO 20200 "Tworzywa sztuczne - Oznaczanie stopnia rozpadu tworzyw sztucznych w symulowanych warunkach kompostowania w skali laboratoryjnej" (ISO 20200:2004). Głównym celem badań było określenie, czy jednorazowe torby ulegają degradacji/biodegradacji czy nie.
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THE EFFECT OF BIODEGRADATION/DEGRADATION OF DEGRADABLE PLASTIC MATERIAL ON COMPOST QUALITY

63%
Adamcová D., Toman F., Vaverková M., Kotovicová J.
Ecological Chemistry and Engineering S
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2013
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vol. 20
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issue 4
783-798
EN
The objective of this study was to find out whether the quality of compost would change during the process of composting carrier bags claimed by manufacturers as compostable or biodegradable in terms of parameters stipulated in the standard ČSN 46 5735 Industrial composts. Eight samples were subjected to the composting process in laboratory conditions. The compost samples were analyzed in the accredited laboratory. All samples met parameters stipulated for Class II. Seven samples of the eight met parameters stipulated in the standard ČSN 46 5735 for Class I. The samples had no influence on compost characteristics: strength, content of water and salt, pH value, content of nutrients or proportion of organic substances; other components of the compost remained unchanged. Optical changes of the compost did not occur either.
PL
Celem badań było określenie wpływu procesu kompostowania „jednorazowych” plastikowych toreb dostępnych na rynku, które są oznaczone jako biodegradowalne/degradowalne, jak również toreb certyfikowanych jako nadające się do kompostu, na jakość kompostu oraz dotrzymania wymagań określonych w normie CSN 46 5735 Komposty przemysłowe. Osiem próbek poddano procesowi kompostowania w warunkach laboratoryjnych. Próbki powstałego kompostu analizowano w akredytowanym laboratorium. Wszystkie próbki spełniały parametry określone w normie dla klasy II. Siedem z ośmiu próbek spełniało parametry określone w normie CSN 46 5735 dla klasy I. Próbki poddane recyklingowi organicznemu nie miały wpływu na właściwości kompostu: konsystencję, zawartość wody i soli, wartość pH, zawartość składników odżywczych lub stosunek substancji organicznych; składniki kompostu pozostały niezmienione. Nie zaobserwowano także zmian w wyglądzie kompostu
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