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1

Biological properties of nanosilver-loaded PMMA bone cement doped with bioactive glass

Wekwejt Marcin, Chen Si, Łukowicz Krzysztof, Pałubicka Anna, Osyczka Maria, Michno Anna, Michálek Martin, Zieliński Andrzej

Engineering of Biomaterials

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2021

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Vol. 24, no. 163

83

2

Computational fluid dynamics simulation of heat transfer from densely packed gold nanoparticles to isotropic media

Radomski Piotr, Ziółkowski Paweł, de Sio Luciano, Mikielewicz Dariusz

Archives of Thermodynamics

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2021

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Vol. 42, no 3

87--113

EN

This work aims to determine and compare heat generation and propagation of densely packed gold nanoparticles (Au NPs) induced by a resonant laser beam (532 nm) according to the Mie theory. The heat flux propagation is transferred into the materials, which here are: silica glass; soda-lime-silica glass; borosilicate glass; polymethyl methacrylate (PMMA); polycarbonate (PC); and polydimetylosiloxane (PDMS). This analysis aims to select the optimum material serving as a base for using photo-thermoablation. On the other hand, research focused only on Newtonian heat transfer in gold, not on non-Fourier ones, like the Cattaneo approach. As a simulation tool, a computational fluid dynamics code with the second-order upwind algorithm is selected. Results reveal a near-Gaussian and Gaussian temperature distribution profile during the heating and cooling processes, respectively. Dependence between the maximum temperature after irradiation and the glass thermal conductivity is observed confirming the Fourier law. Due to the maximum heating area, the borosilicate or soda-lime glass, which serves as a base, shall represent an excellent candidate for future experiments.

3

Herbatka u Calineczki, czyli szkło i ceramika w miniaturze

Jusiak Zofia, Popiel-Machnicka Aneta

Szkło i Ceramika

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2020

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R. 71, nr 1

40--42

PL

Wizyta w Muzeum Domków dla Lalek w Warszawie to fascynująca podróż w czasie, podczas której zobaczyć można blisko 150 historycznych domów, pokoi, sklepów, szpitali, szkół, izb ludowych, a nawet świątyń, kaplic i ołtarzy dla lalek.

4

Zmiana kształtu soczewki wywołana naciskiem oprawy okularowej

Bednarski Arkadiusz, Karp Dariusz

Optyka

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2019

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Nr 4

62--64

PL

Artykuł oparty jest na pracy dyplomowej pod tytułem „Zmiana kształtu soczewki wywołana naprężeniami oprawy okularowej”. Badania uwzględniają parametry soczewek okularowych takie jak moc czołowa, jakość odwzorowanego obrazu, powłoki antyrefleksyjne – zaprezentowano zmiany tych właściwości pod wpływem koncentrycznego nacisku na soczewkę. Wykonano doświadczenia z użyciem pierścienia zaciskowego z możliwością zmiany średnicy. W środku obejmy umieszczano kolejne soczewki o różnych mocach z przedziału od -4,00D do +4,00D z materiału CR-39 i dokonywano kolejnych pomiarów mocy czołowej tylnej, obserwacji rozkładu naprężeń na polaryskopie oraz odwzorowania testu dystorsji przez obciążoną soczewkę. Zostały postawione założenia, że zbyt duże naprężenia mogą skutkować modulacją mocy optycznej poprzez zmianę kształtu soczewki. Kolejne konsekwencje to uszkodzenia krawędzi soczewek, przerwanie uszlachetniających powłok naniesionych na powierzchnię oraz spowodowanie pogorszenia jakości odwzorowanego obrazu.

EN

The article is based on a diploma thesis entitled „Change in lens shape induced by tension of the frame”. The research takes into account the parameters of spectacle lenses such as vertex power, the quality of the image, antireflection coatings – the changes in these properties are presented under the influence of concentric pressure on the lens. Experiments were performed using a clamp ring with the possibility of changing the diameter. In the center of the clamp there were placed other lenses with different spherical powers from -4,00D to +4,00D made from CR-39 material and subsequent measurements of the vertex power, observation of the stress distribution on the polariscope and projection of the distortion test throw lens under pressure were made. The assumptions have been made that too high stresses can result in modulation of the optical power by changing the shape of the lens. Further consequences include damage to the edges of the lenses, interruption of antireflection coatings applied to the surface and causing deterioration of the quality of the projected image.

5

Germanate glasses co-doped with Ce3+/Ln3+ (Ln = Pr, Tb, Dy) for white light emitting diodes

Górny Agata, Sołtys Marta, Pisarska Joanna, Pisarski Wojciech A.

Optica Applicata

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2019

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Vol. 49, nr 3

383--391

EN

Glasses doped with lanthanides ions may be good white light emitters due to their interesting physical and spectroscopic properties. In this paper, the optical spectroscopy of rare earths doped glasses with a special emphasis on application as white LED were presented. The luminescent glass materials containing Ln3+ (Ln = Pr, Tb, Dy) and Ce3+ ions were obtained. The glasses samples were prepared by a traditional melt-quenching technique. The optical properties of glasses containing various concentrations of rare earth ions were analyzed. It was observed that luminescence bands corresponding to characteristic transitions of Ln3+ and cerium ions are present on spectra measured under direct excitation of Ce3+. Therefore, it indicates that the energy transfer process between Ce3+ /Pr3+, Ce3+ /Tb3+, Ce3+ / Dy3+ ions in glasses occurs. Some parameters such as correlated color temperature (CCT) and chromaticity coordinates (CIE) that characterize white LEDs were analyzed and discussed in detail.

6

The biological role of CaO/SiO2 ratio and P2O5 content in sol-gel bioactive glasses incorporated into PLGA

Lukowicz Krzysztof, Zagrajczuk Barbara, Cholewa-Kowalska Katarzyna, Łączka Maria, Osyczka Anna M.

Engineering of Biomaterials

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2019

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Vol. 22, no. 153 spec. iss.

83

7

Osteogenic potential of experimental bioactive surfaces in BMP-responsive mouse osteoblastic cells and human adipose derived ASC52telo cell

Nowak A., Cholewa-Kowalska Katarzyna, Łączka Maria, Osyczka Anna Maria

Engineering of Biomaterials

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2019

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Vol. 22, no. 153 spec. iss.

84

8

Bioactive glasses: benefits and drawbacks for use in bone tissue engineering

Massera Jonathan

Engineering of Biomaterials

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2019

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Vol. 22, no. 153 spec. iss.

8

9

Specjalistyczny zastęp ratowników z KWK „Pniówek”

Skrzydło Andrzej, Markowski Waldemar, Sojka Marek

Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie

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2019

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nr 11

9--12

PL

W artykule opisano przykładowe akcje ratownicze i prace szczególnie odpowiedzialne, wykonane przez zespół specjalistów ratowniczych z „Wysokościowego zastępu ratowniczego do prac w wyrobiskach pionowych i o dużym nachyleniu KWK »Pniówek« z wykorzystaniem technik alpinistycznych”. Przedstawiono również nowoczesny sprzęt alpinistyczny stosowany przez ratowników – alpinistów.

EN

n 1998, a "High-altitude rescue team for works in vertical and steep slope excavations of the Pniówek coal mine with the use of climbing equipment" , consisting of 22 rescuers, was established as of 1/08/2019. The basic climbing equipment used by the team is manufactured by Petzl: Avao Bod Croll Fast harness, ASAP fall--arrester, self-braking descenders with auto-lock function I'D or RIG and Ascension handled rope clamp for rope ascents. The members of the team, in addition to works related to the inspection and repair of coal tanks and shafts without hoisting equipment, take part in rescue operations and various types of particularly responsible tasks. The first rescue operation was carried out by the members of the team already in 1999, during the liquidation of shaft III in the Morcinek coal mine. In 2005, an injured employee who fell into a retention tank at the level of 830 m in the Pniówek coal mine was evacuated. Subsequently, the rescue team performed works related to: reconstruction of the ventilation duct in the area of the ventilation shaft V of the "Pniówek" coal mine – in 2007; replacement of the elevation sheathing of the "Ludwik" shaft tower – in 2010; removal of the consequences of breaking and falling of the power cable into shaft II of the "Zofiówka" coal mine – in 2014. A very complicated task carried out by the high-altitude team were the works performed in 2016 in shaft V of the Pniówek coal mine. The safety works in the shaft were carried out by a high-altitude mine rescue team, instead of an external company, which saved money and time.

10

Sektorowy Program „Innowacyjny Recykling”

Poznański K.

Recykling

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2016

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nr 2

50--51

PL

W imieniu przedsiębiorców reprezentujących kilka kluczowych przemysłów recyklingowych w Polsce w ub.r. złożony został w Narodowym Centrum Badań i Rozwoju wniosek o ustanowienie Programu Sektorowego „Innowacyjny Recykling”.

11

Direct crystallization of silicate-phosphate glass from NaMgPoO4-SiO2 system

Wajda A., Długoń E., Sitarz M.

Engineering of Biomaterials

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2016

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Vol. 19, no. 138 spec. iss.

121

12

Sonic characterization of porous Si3N4 produced by various pore formers

Topateş G., Eren Gültekin E.

Journal of Achievements in Materials and Manufacturing Engineering

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2014

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Vol. 63, nr 1

13--18

EN

Purpose: Study aims to investigate the elastic properties of porous Si3N4 thus three different starch type as pore former additives were used to obtain different pore characteristics. Design/methodology/approach: Porous Si3N4 ceramics were fabricated by partial sintering and pore former addition. Pore formers consisted of elliptic, round and angular particles were used. Elastic, shear and bulk moduli of the samples were measured by ultrasonic measurement using ultrasonic A-scan. Findings: Starches whose particles are isometric and angular lead to higher elastic properties thus it’s possible to tailor the elastic properties by using pore formers with different morphologies. Starches whose particles are isometric and angular lead to higher elastic properties thus it’s possible to tailor the elastic properties by using pore formers with different morphologies Research limitations/implications: The porosity of fabricated ceramics varied between 50-70% and pore size were restricted to around 1 μm as a result of a small grain width of beta-Si3N4 grains and interlocking structure formed by these grains. Practical implications: The Young’s (elastic) modulus of sample without pore former was 30 and it decreased to 10-17 GPa by using different pore formers. Same trend also observed for shear modulus. Originality/value: Even though using similar size and same amount of pore former, slight differences were observed as a result of different geometry of pore former particles and hence pore geometry.

13

Wpływ okularów ajurwedyjskich na układ wzrokowy człowieka

Frąckowiak S., Przekoracka-Krawczyk A., Naskręcki R.

Optyka

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2011

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Nr 4

43--46

PL

Celem badań przeprowadzonych w ramach niniejszej pracy było zbadanie długotrwałego wpływu okularów ajurwedyjskich na układ wzrokowy człowieka. W szczególności sprawdzono, jaki rodzaj zmian w układzie wzrokowym człowieka wywołują okulary ajurwedyjskie. Do badań i analizy wybrano następujące parametry: ostrość wzroku, stan refrakcji, forię z zakresami wergencji, amplitudę akomodacji, położenie punktu bliskiego oraz odpowiedź akomodacji. Osiem osób, stanowiących próbę badawczą, zostało przebadanych dwukrotnie. Pierwsze badanie miało na celu określenie wartości wyjściowych parametrów. Następnie badani zobowiązali się nosić okulary ajurwedyjskie godzinę dziennie przez sześć tygodni. Powtórne badania wykazały, że użytkowanie okularów ajurwedyjskich nie zmienia refrakcji, amplitudy akomodacji oraz forii do dali. Zmianie ulega natomiast ostrość wzroku, foria do bliży oraz odpowiedź akomodacji.

EN

Long-term influence of ayurvedic glasses on human visual system was checked in this research. For eight patients such selected parameters as visual acuity, refraction, phoria and fusional vergence ranges, amplitude of accommodation, near point position and accommodation response were tested during six weeks. During this time, the patients were obliged to wear ayurvedic glasses one hour every day. As it turned out, there has not been a change in refraction, amplitude of accommodation or distance phoria. However, there has been a change in visual acuity, near phoria and accommodation response.

14

Borate glasses with PbO and PbCl2 containing Dy3+ ions

Pisarska J.

Optica Applicata

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2010

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Vol. 40, nr 2

367--374

EN

Oxychloroborate glasses containing Dy3+ ions in the B2O3–PbCl2–PbO–Al2O3–WO3 system were studied using X-ray diffraction, Raman, FT-IR, absorption, excitation and luminescence spectroscopy. The results concerning glass preparation, short-range order structure and optical properties are reported. X-ray diffraction analysis evidently indicates that the fully amorphous system was prepared. Coexistence of trigonal BO3 and tetrahedral BO4 units was evidenced by Raman and FT-IR spectroscopy. The electronic states belonging to the 4f9 configuration of trivalent Dy3+ were determined from the absorption and excitation spectra. The luminescence bands at 480, 573 and 662 nm were registered in oxychloride glasses, which correspond to transitions originating from the 4F9/2 state to the 6HJ/2 (J = 11, 13, 15) states of Dy3+.

15

The thermal stability, local structure and electrical properties of lithium-iron phosphate glasses

Jóźwiak P., Garbarczyk J. E., Wasiucionek M., Gorzkowska I., Gendron F., Mauger A., Julien C.

Materials Science Poland

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2009

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Vol. 27, No. 1

307--318

EN

Amorphous analogues of lithium-iron phosphates (LFP), which are promising cathode materials for Li ion batteries, were prepared by the standard press-quenching method and their thermal stability, as well as structural and electrical properties, were studied for the first time. The glass transition temperature, Tg, determined by the differential thermal analysis (DTA) is composition-dependent and lies in the 492-523 °C range. The local structure, studied by the FTIR absorption spectroscopy, and the thermal stability are found to be almost insensitive to the lithium content. Studies on the electrical properties, carried out by impedance spectroscopy, have shown that the total electrical (predominantly polaronic) conductivity at 450 °C approaches 10-2 Socm-1. The room temperature conductivity of samples after their nanocrystallization (induced by annealing at the temperature of the beginning of crystallization) was higher by a factor of 4-10 (depending on composition) than that of the as-received glass. Therefore, nanocrystallization seems to be a promising way to enhance the electrical conductivity of amorphous lithium-iron phosphates.

16

Silicon nitride ceramics - review of structure, processing and properties

Hampshire S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 1

43-50

EN

Purpose: The purpose of this review is to examine the development of silicon nitride and the related sialons and their processing into a range of high-grade structural ceramic materials. Design/methodology/approach: Silicon nitride is one of the major structural ceramics that possesses high flexural strength, good fracture resistance, good creep resistance and high hardness. These properties arise because of the processing route which involves liquid phase sintering and the development of microstructures in which high aspect ratio grains and intergranular glass phase lead to excellent fracture toughness and high strength. Findings: This review has examined the development of silicon nitride and the related sialons and their processing into a "family" of structural ceramic materials with high hardness, strength, fracture toughness, creep resistance and wear resistance. Practical implications: The development of knowledge of microstructure-property relationships in silicon nitride materials is outlined, particularly recent advances in understanding of the effects of grain boundary chemistry and structure on mechanical properties. Originality/value: This review should be of interest to scientists and engineers concerned with the processing and use of ceramics for engineering applications.

17

Calculations of second-order nonlinear optical suscetibilities in glasses

Golis E. P.

Prace Naukowe. Chemia i Ochrona Środowiska / Akademia im. Jana Długosza w Częstochowie

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2005

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Vol. 10

109--115

18

EPR and optical properties of Li₂B₄O₇:Mn glass samples under the influence of y-irradiation and annealing

Podgórska D., Kaczmarek S. M., Włodarski M., Kwaśny M., Warchoł S., Rizak V. M., Drozdowski W., Berkowski M.

Biuletyn Wojskowej Akademii Technicznej

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2005

|

Vol. 54, nr 1

45-59

EN

Li₂B₄O₇ glasses doped with Mn²⁺ (0.1 mol. %), have been investigated using electron paramagnetic resonance (EPR) method at 9.4 GHz. Mn ion is found enter substantially for the Li⁺ ion as Mn²⁺ and/or Mn¹⁺, and, probably for the B³⁺ ion or interstitial as Mn³⁺. In consequence at least two types of the manganese ions arise in the EPR spectrum in the same range of magnetic field. The EPR spectrum of glass system exhibits three resonance signals, at g ≈ 2.00, g ≈ 2.68 and g ≈ 4.60 and is very similar to others reported for Mn²⁺ ions glass systems. Only 620 nm emission was observed in the photoluminescence spectrum of the "as-grown" glass, while 430 nm and 610 nm emissions in radiolu-minescence spectrum of the system. Four month after ɣ-irradiation we observed three emission peaks centered at 430, 540 and 620 nm. The 430 nm emission was excited with 225, 277 and 374 nm absorption, the 540 nm emission was excited with 225 and 411 nm absorptions, and the 620 nm emission was excited with 225, 360, 411 and 550 nm absorptions.

PL

Badano szkła Li₂B₄O₇ domieszkowane Mn (0,1 mol %) wykorzystując metodę elektronowego rezonansu paramagnetycznego dla częstotliwości 9,4 GHz. Stwierdzono, że jon Mn podstawia się w położenie jonu Li⁺ jako Mn²⁺ oraz/lub jako Mn¹⁺, a także prawdopodobnie w położenie jonu B³⁺ jako Mn³⁺. W konsekwencji, co najmniej dwa rodzaje jonów Mn reprezentowane są w widmie EPR. Widmo EPR szkła LBO domieszkowanego Mn wykazuje obecność trzech sygnałów rezonansowych, dla g ≈ 2,00, g ≈ 2,68 oraz g ≈ 4,60. W przypadku szkła LBO:Mn badanego tuż po wzroście, w widmie fotoluminescencji stwierdzono obecność emisji z maksimum dla 620 nm, zaś w widmie radioluminescencji emisji 430 nm i 610 nm. Naświetlenie tego szkła kwantami gamma przesuwa widmo emisji w stronę fal długich obniżając jego intensywność, Cztery miesiące po tym naświetleniu w widmie fotoluminescencji obserwuje się dodatkową emisję dla 540 nm wzbudzaną przez absorpcję dla 225 nm i 411 nm.

19

EPR and optical properties of Li₂B₄O₇:Mn and Li₂B₄O₇:Eu, Mn single crystals under the influence of ɣ-irradiation and annealing

Podgórska D., Kaczmarek S. M., Drozdowski W., Kwaśny M., Warchoł S., Rizak V. M., Berkowski M.

Biuletyn Wojskowej Akademii Technicznej

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2005

|

Vol. 54, nr 1

61-80

EN

Single crystals of Li₂B₄O₇ doped with Mn²⁺ (0.014 mol %) and co-doped with Mn (0.005 mol %) and Eu³⁺ (0.5 mol %) have been investigated using EPR method at 9.4 GHz. In both systems the Mn ion is found to enter substantially for the Li⁺ ion as Mn²⁺ and/or Mn¹⁺, and, probably for the B³⁺ ion or interstitial as Mn³⁺. In consequence at least two types of the manganese ions arise in the EPR spectrum in the same range of magnetic field. In the EPR spectrum of Li₂B₄O₇:Mn crystal one can recognize g ≈ 2.00 and, g ≈ 2.89 lines. Annealing in the Ar atmosphere does not significantly change the spectrum (g = 1.97(8)) while irradiation with ɣ-quanta with a dose of 5 x 10⁴ Gy decreases to some extent the intensity of Mn²⁺ EPR signal (g = 1.99 ± 0.01) introducing new EPR line (g = 2.14 ± 0.01), giving evidence on formation of other (Mn¹⁺, Mn⁶⁺, Mn⁰) valence states of manganese. Moreover, F-type and/or Vk color centers are formed. The optical investigations of "as-grown" and ɣ-irradiated samples were performed giving evidence on Mn⁰ and Mn⁶⁺ formation in the crystal after y-irradiation. 430 nm and 610 nm emissions in radioluminescence spectrum of both systems we observed. Measurements of the crystals reveal the strong thermoluminescence peak at about 95 K, assigned probably to F⁺ center and smaller ones assigned to manganese at different valence states.

PL

Badano monokryształy Li₂B₄O₇ domieszkowane Mn²⁺ (0,014 mol %) oraz kodomieszkowane Mn²⁺ (0,005 mol %) i Eu³⁺ (0,5 mol %) wykorzystując metodę elektronowego rezonansu paramagnetycznego dla częstotliwości pola magnetycznego 9,4 GHz. W obu systemach jon Mn podstawia się w położenie jonu Li⁺ jako Mn²⁺ oraz/lub jako Mn¹⁺, a także prawdopodobnie w położenie jonu B³⁺ jako Mn³⁺. W konsekwencji co najmniej dwie linie rezonansowe obserwuje się w widmie EPR tych kryształów, g ≈ 2,00 oraz g ≈ 2,89. Wygrzewanie w argonie nie zmienia tego widma (g = 1,97(8)), podczas gdy naświetlanie kwantami gamma dawką 5 x 10⁴ Gy znacznie zmniejsza intensywność sygnału rezonansowego jonu Mn²⁺ (g = 1,99 ± 0,01) wprowadzając dodatkową linię (g = 2,14 ± 0,01), która dokumentuje obecność w krysztale jonów Mn (Mn¹⁺, Mn⁶⁺, Mn⁰) o innym niż 2 stanie walencyjnym. Ponadto powstają centra barwne typu F oraz Vk. Przeprowadzono badania absorpcji kryształów naświetlonych kwantami gamma, które potwierdziły obecność w naświetlonych kryształach jonów atomów Mn⁰ i jonów Mn⁶⁺. W widmie radioluminescencji obserwowaliśmy emisje z maksimami dla 430 nm i 610 nm. Badania termoluminescencji pokazały silny pik termoluminescencji dla około 95 K, związany prawdopodobnie z centrum F⁺ i znacznie mniej intensywne piki, które można przypisać jonom Mn o różnych walencyjnościach (od 0 do 6).

20

Fiber Reinforced Transparent Glass

Hülsenberg D., Fehling P., Leutbecher T., Raab D.

Machine Dynamics Problems

|

2004

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Vol. 28, No. 3

131-137

EN

The paper deals with different (matrix) glasses reinforced with coated Nextel 440 fibers. The mechanical properties of the composite materials depend strongly on the thermal expansion difference between matrix and fiber and on the type of fiber coating. A fiber pullout during loading is desired in order to get a damage tolerant behaviour. But not each from the mechanical point of view successful fiber/matrix pair is suitable for a transparent composite. Such a transparent composite demands fibers and a matrix glass with adapted refractive index, without internal stress and holes, and fiber coating which does not influence the optical transmission in the visible wavelength range. The Nextel 440 fiber (produced by 3 M) and the code 8650 matrix glass (produced by Schott) are fitted components. The coating should be a double layer for sliding and protecting. Moreover a hot pressing process in oxydizing atmosphere is helpful.