Wyniki wyszukiwania - Biblioteka Nauki

1

Properties of films fabricated from ZnS/Mn2+ nanoparticles

100%

Zdyb A. , Cieślak K. , Olchowik J. M.

Materials Science Poland

|

2008

|

tom Vol. 26, No. 2

389--394

EN

Nanoparticles of manganese doped zinc sulfide (ZnS/Mn2+) were obtained by wet chemical method. AFM images of the nanoparticles were analysed and their size distribution was estimated. The layer of ZnS/Mn2+ nanoparticles reveals a semiconducting character. Conductivity increases with temperature and its value is of the order of 10-9 źcm-1.

2

Nanoengineered hybrid silica/organic nanoparticles and ionized gases for bone regeneration through smart scaffolds

80%

Thomann J. S. , Chekireb M. C. N. , Langueh C. , Changotade S. , Rohman G. , Corne G. , Duday D.

Engineering of Biomaterials

|

2018

|

tom Vol. 21, no. 148

60

3

A comparative study of biosynthesized marine natural-product nanoparticles as antifouling biocides

80%

Abdelsalam K. M. , Shaltout N. A. , Ibrahim H. A. , Tadros H. R. Z. , Aly-Eldeen M. A.-E. , Beltagy E. A.

Oceanologia

|

2022

|

tom No. 64 (1)

35--49

EN

In this study, biosynthesized nanoparticles using chitosan, Ulva fasciata, and Avicennia marina leaves extracts (A, B, and C, respectively), were evaluated as paint additives to control marine fouling on different substrates. These biocidal nanoparticle compounds were prepared using a green biosynthesis method. Their characterizations were conducted using Fourier-Transform Infrared spectroscopy and Transmission electron microscopy. Each nanoparticle compound was mixed with a prepared paint, resulting in three formulations for each (e.g. 1C, 2C, 3C), containing 20%, 40%, and 60% by weight. Painted PVC, wood, and steel with these nine paints, and the control were immersed in seawater for different periods. After two months of immersion, the least number of fouling species, (one species) was recorded on both the wood and steel panels that were coated with paint (1C). Meanwhile, after four months, the least numbers of fouling (four and six species) were recorded on wood and steel panels that were coated with paint (3C). After around seven months of immersion, the least numbers of fouling species (five and ten) were recorded on wood and steel panels that were coated with paints (1C and 3C), respectively. The steel panel coated with (3C), harbored ∼2% of the total number of barnacles found on the control, after 7 months of immersion. The superior antifouling agent efficiency of extract (C) nanoparticles can be attributed to its constituents of polyphenols, ammonium compounds, and high concentrations of alcohols, besides the presence of both aromatic and aliphatic amide and amide derivatives.

4

Nonoparticles materials in diesel particular filtres

80%

Merkisz J. , Fuć P. , Lijewski P.

Logistyka

|

2010

|

tom nr 6

EN

The reduction of platinum (Pt) loadings in the catalytic bed constitutes a primary means of reducing cost to the levels required for mass- produced vehicles. We have produced and tested, on the laboratory scale a series of innovative catalysts as an active part of a new PM- filter consisting of Pd-Au-Ag-Ni-Co (non Pt) nanometric, powder alloy. The hollow part structure of TiO2-x-RuO2-x has been proposed as the active layer on the catalyst support, composed of SiC. We have previously demonstrated that single layers of Pt atoms on some other materials, such as palladium (Pd) or gold- nickel alloys, have higher activities than the analogous all-Pt catalysts. Such control of the composition and structure of the top-most atomic layers of catalyst particles gives hope of achieving the four-fold increase in mass activity catalysts needed to reach automotive catalyst cost targets.

5

Effect of Nanoparticles on the Performance of Solar Flat Plate Collectors

80%

Hamdan M. , Sarsour M.

Journal of Ecological Engineering

|

2018

|

tom Vol. 19, nr 2

1--7

EN

Solar energy constitutes superior renewable source due to its availability, natural distribution and no necessity for transportation. It can be designed to fulfill the requirements of power demands, and can work in synchronization with battery banks and diesel generators or any other power source to provide a continuous and stable power. Solar energy is already one of the best solutions to fulfill power demands. A solar thermal collector is a key element for the collection and conversion of solar energy into thermal energy. There are different types of solar collectors, the most important one is the conventional 'Flat-Plate' kind, which absorbs the incident radiation and converts it to thermal energy. The main objective of this work is to study the effect of Titanium Oxide (TiO2) and Zinc Oxide (ZnO) water-based nanofluids on the performance of solar flat plate collector. In order to achieve this objective, three identical flat plat solar collectors were used with appropriate instrumentations necessary to experimentally calculate their performance. The working fluid in the first collector was pure water, while in the second collector, it was Titanium Oxide water-based nanofluid and in the third one – Zinc Oxide water-based nanofluid. Two different values of volume fraction of both oxides were used as well. It was found that the addition of Titanium Oxide and Zinc Oxide nanoparticles leads to an increase in the efficiency of the solar collector. The efficiency of the collector was found to be maximum over all values of (Tin – Tamb) when a 0.2% volume fraction of Titanium Oxide was used with a maximum efficiency of 40%, followed by the case of 0.6% volume fraction of Titanium Oxide. Furthermore, zinc oxide caused a maximum improvement in the performance of solar flat plate collector when 0.6% was used, followed by 0.2% concentration. Finally, it was found that titanium oxide is characterized by more pronounced improvement in the performance of solar flat plate collector.

6

Active sol-gel powders.

80%

Borek B. , Jasierski M. , Laskowski S. , Mazurek B. , Maruszewski K.

Prace Naukowe Instytutu Podstaw Elektrotechniki i Elektrotechnologii Politechniki Wrocławskiej. Konferencje

|

2006

|

tom Vol. 44, nr 18

146-148

EN

The sol-gel technology provides a relatively simple and cheap method of production of submicron-sized powders. Also, due to its wet-chemistry character doping and chemical modifications of such powders are fairly straightforward. Enables it obtaining various active powders for a broad possible variety of applications.

7

One-step fabrication of gentamicin nanoparticles embedded in polymeric biomaterials surface: sonochemical approach

80%

Gołda-Cępa M. , Chytrosz P. , Kotarba A.

Engineering of Biomaterials

|

2017

|

tom Vol. 20, no. 143 spec. iss.

20

8

Application of neutron activation for investigation of Fe3O4 nanoparticles accumulation by plants

80%

Bystrzejewska-Piotrowska G. , Asztemborska M. , Stęborowski R. , Polkowska-Motrenko H. , Danko B. , Ryniewicz J.

Nukleonika

|

2012

|

tom Vol. 57, No. 3

427-430

EN

As a result of the rapid development of nanotechnology and increasing application of nanoproducts in many areas of everyday life, there is a growing risk of production of nanowastes potentially dangerous for the environment. This makes it necessary to investigate the accumulation and toxicity of nanoparticles (NPs) at different trophic levels. In the studies neutron activation was applied for the investigation of iron (II,III) oxide nanoparticle (Fe3O4-NPs) accumulation by Lepidium sativum and Pisum sativum L. Plants were cultivated on growth medium contaminated with different concentrations (0.01-10 mmolźL-1) of Fe3O4-NPs. For the identification of the presence of Fe3O4-NPs in plant tissues gamma spectrometry following iron oxide (II,III) nanoparticles irradiation was applied. Both plant species were found to accumulate iron (II,III) oxide nanoparticles. The highest content of NPs was found in plant roots, reaching 40 g/kg for Pisum sativum L. More than 90% of accumulated NPs were found in roots. Accumulation of Fe3O4-NPs was found to depend on the concentration of nanostructures in the growth medium. The transfer factor for Lepidium sativum roots and shoots and Pisum sativum L. shoots decreased with increasing NP concentration in the medium; for Pisum sativum L. roots the tendency was reversed. Neutron activation of nanoparticles was shown to be a powerful tool for tracing the environmental fate of NPs and their uptake and accumulation in organisms.

9

Decoration of electrospun fibers with chitosan nanoparticles loaded with essential oils for bactericidal and anti-inflammatory application

80%

Wilgocki-Ślęzak J. , Irusta S. , Kyzioł A.

Engineering of Biomaterials

|

2017

|

tom Vol. 20, no. 143 spec. iss.

32

10

Microstructure and properties of alloyed silver-gold nanoparticles

80%

Prymak O. , Ristig S. , Meyer-Zaika W. , Raabe D. , Epple M.

Engineering of Biomaterials

|

2014

|

tom Vol. 17, no. 128-129

77

EN

Alloyed silver-gold nanoparticles recently raised an interest in biomedicine as potential antibacterial and surface-functionalized agents for imaging, drugdelivery, and tumor thermo-therapy [1,2]. The here synthesized alloyed AgAu nanoparticles with different compositions of silver and gold, as determined by atomic absorption spectroscopy (AAS), were prepared by reduction with citrate and tannic acid in aqueous media and subsequently functionalized by the addition of polyvinylpyrrolidone (PVP) [3]. UV spectroscopy confirmed that the particles consisted of alloyed Ag:Au and are not of a separate core-shell structure. The resulting nanoparticles were monodisperse and had a uniform size of ~6 nm, except pure Ag and Ag:Au-90:10, as shown by differential centrifugal sedimentation (DCS) and transmission electron microscopy (TEM). By means of X-ray powder diffraction (XRD) and use of Rietveld refinement [4], the precise lattice parameters, crystallite size and microstrain were determined. Based on the results by XRD, DCS and TEM it was shown, that the nanoparticles were not twinned, except pure Ag and Ag:Au-90:10. Additionally, a distinct deviation from Vegard’s linear rule of alloy mixtures for the lattice parameter was found for the nanoparticles. This effect was also found for AgAu bulk materials, but was much more pronounced in the nanostate. Further investigations of the crystal structure of the alloyed nanoparticles by means of synchrotron radiation might be helpful to gain more information about the interactions of silver and gold atoms.

11

Herbal Extract-Induced Silver Nanoparticles for Antibacterial Cotton Fabric

80%

Rajput S. K. , Singh M. K. , Shakyawar D. B.

Fibres & Textiles in Eastern Europe

|

2023

|

tom Vol. 31, no. 3

22--29

EN

Herbal extract-induced metallic nanoparticles have replaced the traditionally synthesized nanoparticles to achieve sustainability in antimicrobial textiles. Silver nanoparticles (NPs) were created by the bio-reducion of silver nitrate with eucalyptus corymbia leaf extract. The bi-lateral activities of herbal extract, like the reduction and capping of silver nanoparticles, have added new dimensions in the bactericidal sector. Silver nanoparticles were characterized by UV-visible spectroscopy, a particle size analyzer, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and X-ray diffractometry. In this study these biosynthesized nanoparticles were applied on cotton fabric alone and along with chitosan by the pad-dry-cure method to create antibacterial clothing. Antibacterial efficiency was characterized using the colony counting method (serial dilution method). The treated fabric shows excellent antibacterial efficiency.

12

Incorporation of zirconia and germania and ternary compounds of ZrO2-GeO2 into silica sol-gel matrices

80%

Gurin V. S. , Alexeenko A. A. , Kasparov K. N. , Tyavlovskaya E. A.

Materials Science Poland

|

2005

|

tom Vol. 23, No. 1

49--60

EN

Silica sol-gel glasses were doped with zirconia and germania. Nanoparticles composed from these oxides and the binary oxides Zr-Ge-O were produced within the matrices. XRD, TEM, and XPS studies were used to determine the phase composition and energy of the electronic states of the elements. The optical features of the materials were chracterized by UV/Visible absorption and photoluminescence. Nanoparticles of ZrGeO4 and Zr3GeO8 within the solid matrices were fabricated for the first time.

13

Nanocząstki jako „nowoczesny” czynnik stresowy dla roślin

80%

Pietrzak M.

Eliksir

|

2018

|

tom nr 2

26--28

14

Adhesion of bacterial films on polymer food films covered by graphene oxide emulsion and graphene nanoparticles

80%

Kopczyńska E. , Czerwińska E. , Mitura K. A.

Engineering of Biomaterials

|

2018

|

tom Vol. 21, no. 148

100

15

Polymer carriers modified by plasma and functionalized with Au nanoparticles as substrates for mouse 3T3 fibroblasts

80%

Bacakova M. , Makajova Z. , Slepickova-Kasalkova N. , Svorcik V. , Bacakova L.

Engineering of Biomaterials

|

2011

|

tom Vol. 14, no. 109-111 spec. iss.

5

EN

Polymers have been o f ten applied in biology and medicine for construction of tissue replacements. However, the inert surface o f the most polymers is not able to support and control cell adhesion, migration, proliferation, differentiation and other cell functions. Hence, the modification of polymer surface led to achieve appropriate properties. The polymer surface can be modified by plasma discharge by which the polymer surface chemistry and morphology is changed. Plasma treatment leads to creation of radicals, unsaturated bonds and new chemical groups, mainly oxygen containing groups. Oxidized groups increase the wettability of polymers, which supports adsorption of cell adhesion-mediating extracellular matrix (ECM) molecules in appropriate spatial conformation increasing accessibility of specific sites in these molecules by cell adhesion receptors. In addition, other surface properties of polymers are altered by plasma etching which strongly influence cell-material interaction. Radicals and unsaturated chemical bonds which are created by plasma can be utilized for grafting new chemical groups, biomolecules and nanoparticles. The biomolecules grafted on the polymer surface, such as amino acids, RGD-containing oligopeptides (i.e., ligands for integrin receptors), ECM molecules, enazymes, hormones, and also carbon and gold nanoparticles, not only have specific biological effects on cells but also change physical and chemical properties of the polymer surface, and by this way they support its bioactivity. This study is focused on physiochemical properties and biocompatibility of modified polymers. The studied materials were poly(L-lactide) (PLLA) foils, nanofibrous PLLA meshes and polyethylene terephtalate (PTFE) foils. PLLA and PTFE foils were modified in plasma with Ar + ions for time intervals of 50, 10 0 and 300 s with power 8 W, and then grafted with Au nanoparticles. Changes in the surface wettability were determined by reflection goniometry . The presence an d concentration o f Au nanoparticles were examine d by X-ray Photoelectron Spectroscopy (XPS). For the biocompatibility testing, the polymers were seeded by mouse embryonic fibroblasts of the line 3T3, i.e., t he cells of ten utilized as a feeder for keratinocytes. The cell adhesion and growth was evaluated by the number of cells, their morphology and the size of cell adhesion area in the 1st, 3rd and 6th day after seeding. The results indicate that the water drop contact angle increases with the time of exposure to plasma, which means that the vettability decreases. However, the following exposure of plasma-irradiated polymers to a sodium citrate solution (i.e., a storage solution for Au nanoparticles) and grafting with Au nanoparticles decrease the contact angle, i.e., increase the material surface wettability. Our tests of biocompatibility indicate that the modification of the polymer surface in fluences positively the cell behavior. The cells adhered at higher numbers and by a larger cell adhesion area on modified polymers; it was mainly manifested on PTFE.

16

Synthesis and study of structural properties of Sn doped ZnO nanoparticles

80%

Javid M. A. , Rafi M. , Ali I. , Hussain F. , Imran M. , Nasir A.

Materials Science Poland

|

2016

|

tom Vol. 34, No. 4

741--746

EN

Pure and Sn-doped ZnO nanostructures were synthesized by simple chemical solution method. In this method we used zinc nitrate and NaOH as precursors. Sn doping content in ZnO was taken with the ratio 0, 5, 10, 15 and 20 percent by weight. Physical properties of Sn-doped ZnO powder were studied by XRD analysis which revealed that Sn doping had a significant effect on crystalline quality, grain size, intensity, dislocation density and strain. The calculated average grain size of pure ZnO was 21 nm. The best crystalline structure was found for 0 wt.%, 5 wt.% and 10 wt.% Sn doping as observed by FESEM and XRD. However, higher Sn-doping (> 10 wt.%) degraded the crystallinity and the grain size of 27.67 nm to 17.76 nm. The structures observed in FESEM images of the samples surfaces were irregular and non-homogeneous. EDX depicted no extra peak of impurity and confirmed good quality of the samples.

17

Gray Water Recovery System Model by Solar Photocatalysis with TiO2 Nanoparticles for Crop Irrigation

80%

Carbajal-Morán H. , Zárate-Quiñones R. H. , Márquez-Camarena J. F.

Journal of Ecological Engineering

|

2021

|

tom Vol. 22, nr 4

78--87

EN

The objective of the study was to establish the configuration of the system model to allow the effective recovery of gray water by solar photocatalysis with TiO2 nanoparticles for irrigation of crops. A programmable solar photoreactor based on an S7 1500 PLC and online measurement sensors were used as materials. The inductive method was used to analyze the samples and the deductive method to determine the water quality. The research design used was experimental based on the response surface methodology (MSR) with 20 experiments, 6 of which were central experiments and 6 were axial experiments; these experiments were carried out on sunny days. As a result of the research, a gray water recovery model was obtained, part of this being an electronic system with a programmable photocatalyst, which allowed the development of the experiments. It was concluded that with a solar UV index of 12.21, a dose of titanium dioxide (TiO2) nanoparticles 1.973 g/L and with an exposure period of 60.041 minutes of the solar photocatalyst to UV radiation on sunny days, gray water was recovered in 90% with a confidence level of 95% and a significance α = 0.05, which translates into excellent quality according to the water quality index established in Peru (ICA-PE).

18

Sonochemical synthesis of drug molecules nanoparticles: towards controlled drug release

80%

Chytrosz P. , Golda-Cepa M. , Kotarba A.

Engineering of Biomaterials

|

2018

|

tom Vol. 21, no. 148

69

19

UV-Vis studies of 800 keV Ar ion irradiated NiO thin films

80%

Mallick P. , Mishra D. K. , Kumar P. , Kanjilal D.

Materials Science Poland

|

2015

|

tom Vol. 33, No. 3

555--559

EN

We report the evolution of optical absorption properties of 800 keV Ar ion irradiated NiO thin films through UV-Vis characterization. Our results indicate the existence of both Mott-Hubbard (d → d transition) and charge-transfer (p ! d transition) characteristic of NiO. The optical band gap of NiO increases from 3.58 to 3.75 eV when irradiated at the fluence of 5 x 1014 ions cm-2 but it does not show any remarkable variation upon 800 keV Ar ion irradiation at higher fluences. The refractive index and electron polarizability at different ion fluences have been determined from the optical band gap. Both refractive index and electron polarizability follow an opposite trend to that of the energy gap as a function of ion fluence.

20

Problemy jakości nowoczesnych środków kosmetycznych

80%

Moskaluk-Grochowicz A. , Szewczyk P.

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

|

2010

|

tom z. 50

5-20

PL

pracy przedstawiono niektóre nowoczesne środki kosmetyczne, zawierające między innymi nanocząstki różnych materiałów, oraz omówiono wyniki badań ankietowych wybranej grupy kobiet w zakresie ich ogólnej wiedzy na temat stosowanych kosmetyków, z punktu widzenia ich jakości oraz potencjalnego wpływu na zdrowie.

EN

In this work some modern cosmetic products containing, between others, nanoparticles of different materials were presented and results of a questionnaire survey of a chosen group of women concerning their general knowledge on the used cosmetics from the point of view of their quality and potential influence on health were discussed.