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1

Improving the Water-Repellent and Antifungal Properties of Electrospun Cellulose Acetate Materials by Decoration with ZnO Nanoparticles

Nachev Nasko, Spasova Mariya, Manolova Nevena, Rashkov Iliya, Naydenov Mladen

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 3 (147)

40--45

EN

Suitable conditions for the preparation of nano- and microstructured materials from cellulose acetate and cellulose acetate/ZnO from solutions/suspensions in aceton/water by electrospinning/electrospraying were found. The materials obtained were characterised by scanning electron microscopy (SEM), X-ray diffraction analysis (XRD) and contact angle measurements. The antifungal activity of the materials obtained against Phaeomoniella chlamydospora, which is one of the main species causing diseases in grapevines, was studied as well. It was found that electrospinning of CA solutions with a concentration of 10 wt% reproducibly resulted in the preparation of defect-free fibres with a mean fibre diameter of ~780 nm. The incorporation of ZnO nanoparticles resulted in the fabrication of hybrid materials with superhydrophobic properties (contact angle 152°). The materials decorated with ZnO possessed antifungal activity against P. chlamydospora. Thus, the fibrous materials of cellulose acetate decorated with ZnO particles obtained can be suitable candidates to find potential application in agriculture for plant protection.

PL

W pracy wskazano odpowiednie warunki do otrzymywania materiałów nano- i mikrostrukturalnych z octanu celulozy i octanu celulozy/ZnO z roztworów/zawiesin w acetonie/wodzie metodą elektroprzędzenia/elektrorozpylania. Uzyskane materiały scharakteryzowano za pomocą skaningowej mikroskopii elektronowej (SEM), dokonano analizy dyfrakcji rentgenowskiej (XRD) oraz pomiarów kąta zwilżania. Zbadano również działanie przeciwgrzybiczne uzyskanych materiałów przeciwko Phaeomoniella chlamydospora, który jest jednym z głównych gatunków wywołujących choroby winorośli. Stwierdzono, że podczas elektroprzędzenia z roztworów CA o stężeniu 10% wag. w sposób powtarzalny otrzymywano włókna wolne od defektów o średniej średnicy ~ 780 nm. Wprowadzenie nanocząstek ZnO zaowocowało wytworzeniem materiałów hybrydowych o właściwościach superhydrofobowych (kąt zwilżania 152°). Materiały z dodatkiem ZnO wykazywały działanie przeciwgrzybiczne przeciwko P. chlamydospora. Stwierdzono, że otrzymane materiały mogą być stosowane w rolnictwie do ochrony roślin.

2

Investigation of the Deposition Time of Electrosprayed Textile Chemicals

Kapar Bilgen, Gunesoglu Cem

Fibres & Textiles in Eastern Europe

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2019

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Vol. 27, no. 2 (134)

74--77

EN

Deposition time should be considered as an important parameter in the assessment of the electrospraying process as an application alternative because it would determine the treatment time and cost of the application. In this study, commercially available textile softeners and liquid repellents on electrosprayed on a collecting ground to statistically investigate the effect of the intrinsic properties of the chemicals and set-up parameters of electrospraying on the deposition time and to find out the mathematical relation between the deposition time and selected parameters. The results showed that the processhad ahigher deposition time when the chemicals were poured in diluted emulsions. Also the chemical type and electric field intensity had a strong contribution.

PL

Czas osadzania jest traktowany jako ważny parametr w ocenie procesu elektrorozpylania jako alternatywa dla aplikacji, ponieważ określa czas obróbki i koszt aplikacji. W pracy poddano elektrorozpyleniu dostępne na rynku środki do zmiękczania tkanin i środki odbarwiające. Środki chemiczne rozpylono na podłożu zbierającym w celu statystycznego zbadania wpływu swoistych właściwości chemikaliów i parametrów ustawiania elektrorozpylania na czas osadzania i w celu znalezienia matematycznego równania określającego zależność między czasem osadzania a wybranymi parametrami. Wyniki wykazały, że proces miał dłuższy czas osadzania, gdy chemikalia były wlewane w rozcieńczone emulsje. Również duży wpływ miały typ chemiczny i intensywność pola elektrycznego.

3

Elektrorozpylanie - dogodny sposób jonizacji analitów w przypadku stosowania bezpośrednich procedur pomiarowych opartych na wykorzystaniu spektrometrii mas

Byliński H., Woźniak M. K., Gębicki J., Namieśnik J.

Analityka : nauka i praktyka

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2018

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nr 3

20--25

PL

Bezpośrednie techniki pomiarowe umożliwiające analizę w czasie rzeczywistym są jednym z najważniejszych kierunków rozwoju współczesnej analityki i bioanalityki.

4

Application of numerical modelling to scaling-up of electrically induced extraction from an organic mixture using an ionic liquid

Kamiński K., Weatherley L.R., Petera J.

Chemical and Process Engineering

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2016

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Vol. 37, nr 1

133--148

EN

Liquid-liquid extraction provides an environmentally friendly process as an alternative to azeotropic distillation, pervaporation and reverse osmosis because these techniques require the use of large amounts of energy, may involve volatile organic compounds, and operation at high pressureIonic liquids (ILs) continue to gain wide recognition as potential environmentally friendly solvents due to their unique properties. However due to their current high cost, their use in industry is seriously limited without an efficient methodology for recovery and recycle. In this paper we describe an innovative methodology for a liquid-liquid extraction process based on an electrically induced emulsion of an ionic liquid as the extracting solvent dispersed in an organic mixture. This offers a most efficient exploitation of the solvent. On the other hand we present our own design of a pilot (semi-industrial) scale extractor based on this methodology and which demonstrates effective recovery of the ionic liquid. In order to achieve this goal we used a numerical modelling tool implemented using our own simulation software based on the finite element method. We also used our original previous experience with generating and investigating liquid-liquid electrosprays using phase Doppler anemometry. Finally we present recommendations for contactor geometry and for the preferred operating conditions for the extractor.

5

Analysis of the morphology and properties of PAN/Bi2O3 composite nanomaterials produced by electrospraying method

Tański T., Matysiak W., Markovičová L., Florek-Szotowicz N., Snopiński P., Krzemiński Ł., Wiśniowski M.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 73, nr 2

176--184

EN

Purpose: The aim of the study was the preparation of the composite nanofibers with the polymer matrix reinforced by the reinforcement phase in the form of Bi2O3 ceramic nanoparticles using the electrospinning method from the 10% PAN/DMF solutions with the mass concentration of Bi2O3 nanoparticles of the order of 5 and 10%, and the investigate their morphology and physical properties as a function of the mass concentration of the reinforcing phase and the applied process parameters. Design/methodology/approach: In order to analyze the structure of the used Bi2O3 nanoparticles were used high-resolution transmission electron microscope (TEM) and X-ray diffraction analysis (XRD). To examine the morphology and chemical composition of the resulting of materials was carried out using a scanning electron microscope (SEM) with energy dispersive spectrometer (EDS). In order to analyze the physical properties of obtained composite materials was made the UV-VIS spectroscopy study, which are then used to determine the band structure of the obtained nanocomposite materials and to determine the effect of mass concentration of the reinforcing phase on the value of the energy band gap. Findings: The influence of parameters of the electrospinning process on morphology of the composite materials and influence of mass concentration of reinforcing phase on electrical structure obtained materials were determined. Practical implications: Analysis of the electrical properties resulting composite material showed that the PAN composite material reinforced ceramic Bi2O3 nanoparticles is a potentially attractive dielectric material which may be used in the field of optoelectronics. Originality/value: The Bi2O3 particles, due to their energy structure and the photocatalytic properties applied as the strengthening phase for polymers fibers and particles are attractive alternative for composite materials from PAN/TiO2 used as the photocatalytic and dielectric materials.

6

Manufacturing And High Temperature Oxidation Properties Of Electro-Sprayed Fe-24.5% Cr-5%Al Powder Porous Metal

Lee K-A., Oh J-S., Kong Y-M., Kim B-K.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2B

1169--1173

EN

Fe-Cr-Al based Powder porous metals were manufactured using a new electro-spray process, and the microstructures and high-temperature oxidation properties were examined. The porous materials were obtained at different sintering temperatures (1350°C, 1400°C, 1450°C, and 1500°C and with different pore sizes (500 μm, 450 μm, and 200 μm). High-temperature oxidation experiments (TGA, Thermal Gravimetry Analysis) were conducted for 24 hours at 1000°C in a 79% N2+ 21% O2, 100 mL/min. atmosphere. The Fe-Cr-Al powder porous metals manufactured through the electro-spray process showed more-excellent oxidation resistance as sintering temperature and pore size increased. In addition, the fact that the densities and surface areas of the abovementioned powder porous metals had the largest effects on the metal’s oxidation properties could be identified.

7

ESI-ion trap multistage and MALDI-TOF mass spectrometry study of protonated per-O-acetyl indole glucosides

Bekesova S., Cmelik R., Humenik M., Kutschy P., Kovacik V.

Chemia Analityczna

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2005

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Vol. 50, No. 1

223-233

EN

Structure of the title compounds -synthetic precursors of phytoalexin analogs- includes per-O-acetylated D-glucose and N-pheny! substituted indole carboxamide or carbothioamide moieties. Fragmentation mechanisms of these compounds have been studied by electrospray (ESI) ion trap (IT) multistage (MSn=1-5) mass spectrometry and matrix assisted laser desorption/ionization time-of-flight (M ALDT-TOF) techniques. In the primary ionization process, per-O-acetylated indole glucoside cationized (H. Na and K) adducts have been observed. Three fragmentation pathways of the protonated molecules are described. Two of the routes are dominated by the cleavage of the saccharidic part, while in the third one the cleavage of aglycons is a predominant process. Fragmentation of the carbonyl group differs from that of the thiocarbonyl analog. The influence of electron-donating or electron-accepting groups of the aromatic ring on the fragmentation pathways is also discussed. The presented theoretical data on the ESI and MALDI behavior of the saccharidic as well as of the indole and phenyl aglycon parts can facilitate structure elucidation of the analogous compounds.

PL

Elementami struktury tytułowych glukozydów - syntetycznych prekursorów analogów • fitoaleksyny - są N-fenylo podstawione karhoksoamidy lub karbotioamidy indolu i per-O-acelylowana D-glukoza. Fragmentację tych związków badano stosując wielostopniowa (MSn, n= 1-5) spektrometrię mas z jonizacją przez elektro rozpylanie oraz spektrometrię mas czasu przelotu z jonizacją przez desorpcję laserową z udziałem matrycy. W pierwszym procesie jonizacji obserwowano kationowane (H, Na, K) addukty glukozydu per-O-acetyl indolu. Opisano trzy drogi frakcjonowania protonowanych cząsteczek. Dwie z nich są zdominowane przez rozszczepienie części sacharydowej. w trzeciej dominuje rozszczepienie części aglikonowej. Fragmentacja grup karbony Iowy cli różni się od fragmenlac j i analogów tiokarbonylowych. Przedyskutowano wpływ grup elektrono-donorowych i elek-trono-akceptorowych w pierścieniu aromatycznym na drogi fragmentacji. Przedstawione teoretyczne dane, dotyczące zachowania się w ESI i MALDI części sacharydowej i części aglikonu indolowego i fenylowego, ułatwiają wyjaśnienie struktury analogicznych związków.