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PL
W pracy pokazano wpływ domieszek na właściwości strukturalne bioszkieł. Przedstawiono sposoby otrzymywania i domieszkowania jonami srebra, miedzi lub żelaza, cienkich warstw bioszkla otrzymanego metoda zol-żel. Określono aktywność bakteryjną Gram-ujemnych pałeczek ropy błękitnej Pseudomonas aeruginosa and Gram-dodatniego gronkowca złocistego Staphylococcus aureus w domieszkowanych próbkach. Zbadano wpływ promieniowania ultrafioletowego na przeżywalność bakterii.
EN
A recent study has shown that the occurrence of structural alteration of the bioglass which accompanies the remarkable change in glass properties depends on the ions to be incorporated. In this paper, the preparation and antibacterial activity of doped with silver, copper and iron (respectively) bioactive glass thin films, obtained by sol–gel processing, are reported. The antibacterial activity against Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus has been examined. The influence of UV irradiation of different doses on these samples has been investigated.
EN
Advances in biomedical materials now make it possible to grow constructs outside the body and to use them for repairing tissues. The following properties of artificial bone replacement materials are important: the mechanical ones and the bioactivity. Composite materials are designed to provide a combination of good mechanical properties (corundum) and bioglass (bioactivity), which cannot be achieved with a single phase material. The influence of the mechanochemical treatment of microcrystalline sintered corundum (MCC) substrates on certain physico-mechanical properties of bioglass composites has been investigated. The composites consist of MCC and glass CaO-P2O5-SiO2 system. The following methods are used: estimation of the MCC degree reduction size: grain size distribution; description of the morphology and biocomposites structure: SEM, AFM; description of certain physico-mechanical properties: adhesion force.
3
Content available remote Relaxation processes on intersurface of bioglass composite materials
EN
The basic problems one encounters when designing materials for medical applications are biocompatibility and mechanical properties. Recently, a development in the technology of composite materials has been observed. Bioactive glasses are used as a coating on porous corundum (good mechanical properties) implant materials. The technique used for producing glass components involves chemical routes, by the sol-gel process. The effect of a physiological solution on the surface properties of bioglasses and composites slightly differing in their chemical compositions has been examined by dielectric spectroscopy and DTA method. The temperature dependence of conductivity has been measured many times during the reduction and annealing processes, i.e., at various reduction and relaxation stages. The layer formation and the type of electrical charge on the surface of an implant plays a significant role in the generation and remodeling of a bone tissue. Moreover, our measurements allow to preliminary identify the transport mechanism in the considered material.
PL
Szkła i amorficzne materiały silnie różnią się właściwościami dynamicznymi od ich krystalicznych odpowiedników. W kryształach typowymi ekscytonami są fonony. Nieuporządkowanie struktury w szkłach obniża średnią drogę wszystkich fononów. W tej pracy przedstawiono model pasmowy dielektryka, w którym znajdują się dodatkowe pasma emisyjne. Źródłem tych pasm są defekty powstające w wyniku oddziaływania roztworu fizjologicznego. Te badania wskazują, że roztwór fizjologiczny wpływa nie tylko na powierzchniową warstwę biomateriału, ale także na strukturę poziomów energetycznych.
EN
Glasses and amorphous materials strongly differ in their dynamic properties from their crystalline counterparts. In crystal the typical excitations are phonons. In glasses disorder reduces the mean free path of all phonons. Typical for glasses are - coexisting with the long wavelength phonons - additional low energy excitations: tunneling and relaxations. In this paper presented the dielectrics band model and addition emission centers took place. The source of this addition levels was the defected influence of physiological solution. These investigations indicate that the solution influence not only for surface of biomaterials, but also on structure on their energy levels.
6
Content available remote Photostimulated defect formation in gel-derived biomaterial
EN
Intensive research in the field of biomaterials proved that introducing bone implants to a human body causes a modification of an electric field connected with the bone surface. It is possible that this may be, to a great extend, the cause of an adverse reaction of the body to the implant. The surface of implant materials may be highly variable depending on the preparation procedure and external agents. The aim of the investigation was to confirm the porosity of the biomaterials (gel glasses, corundum and cement), using a scanning and optical microscope, and thermoluminescence. The charge transfer was measured by a photo-stimulated exoemission method. The measurement results prove a high sensitivity of our experimental method to the effects of the surface glass modifications. Moreover, the results of our measurements allow preliminary identification of the transport mechanism in the material under consideration.
7
Content available remote Optical and structural properties of sol-gel derived bioactive glasses
EN
The preparation of sol-gel derived bioactive glass thin films coated on corundum has been described. Their morphology and physicochemical features were characterized by means of XRD, SEM and UV-VIS-IR methods.
8
Content available remote Radiation-induced paramagnetic centers in Bioglass(R).
EN
The X-band (v=9.4 GHz) electron spin resonance (ESR) and thermally stimulated luminescence (TSL) spectra of the UV-, X-, and gamma -irradiated Bioglass(R) samples of different composition (Bioglass(R) I and Bioglass(R) II) have been investigated. The efficiency of generation of electron and hole centers strongly depends on basic Bioglass(R) composition and is almost independent of ionizing radiation type and presence of Fe/sup 3+/ non-controlled impurity in the glass network. The spin Hamiltonian parameters (g and a values) and thermal stability of the radiation-induced centers have been evaluated. The results of TSL measurements show good agreement with ESR data. The energetic structure, formation peculiarities and specific models of the radiation-induced paramagnetic centers in the Bioglass(R) network are discussed.
PL
W pracy przebadano wpływ 3 typów roztworów fizjologicznych na właściwości powierzchniowe implantów kości. W wyniku oddziaływania roztworu fizjologicznego na tworzywo hydroksyapatytowe i zmodyfikowane bioszkła na ich powierzchni powstaje naładowana warstwa. Ten ładunek powierzchniowy był mierzony metodą optycznie stymulowanej exoemisji elektronów, której wyniki potwierdzają występowanie w modelu pasmowym tych dielektryków dodatkowych centrów emisji powstających pod wpływem defektującego działania roztworów modyfikujących materiał. przeprowadzone badania dowodzą, że roztwory wpływają nie tylko na powierzchnie biomateriałów, ale także na ich strukturę poziomów energetycznych. Na stabilność generowanego ładunku ma również wpływ długość fali ultrafioletu stymulującego proces emisji ładunku z powierzchni materiałów. Przeprowadzono dyskusje możliwych mechanizmów zmiany w czasie ładunku generowanego na powierzchni.
EN
In this paper influence of 3 type of physiological solution on the surface properties was investigated. As result of the initial ion exchange process on the surface of biomaterials a charge layer is formed. This surface charge was investigated by optical stimulated exoelectron emission. In this dielectrics band model an addition emission centers took place. The mean value of the emission intensity is reproducible, but the source of this addition levels was the defected influence physiological solution. These investigations indicate that the solution influence not only for surface of biomaterials, but also on the structure of their energy levels. On the stability of generation of charge, the wavelength of UV stimulated light was influenced. We discuss the possibility of probable mechanism of charge transfer on the surface.
10
Content available remote Electron emission stimulated by waveguide radiation.
EN
The influence of laser light simulation on electron emission from planer waveguide surface has been investigated. The measurement technique proposed by Zatsepin has applied to simulate electron emission under the action of intrinsic UV radiation of the waveguide. the results obtained are discussed in terms of point defects in the structure.
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