10 research outputs found

    Оценка точности химико-аналитических приборов по результатам их градуировки

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    In the production of micro devices for applications in chemistry, biotechnology and medical technologies surface properties become more and more important The microscale topography and surface chemistry have influence on wetting properties and cell behavior. Therefor the design of material surface determines the success of artificial devices in contact with biological systems. For applications in the field of medical implants laser technologies have been developed for micro structuring of polymers to modify the surface properties with respect to wettability and controlled cell growth. The technology is based on excimer laser treatment of polymer surfaces using laser wavelength 193 nm (ArF) with different fluences and cumulated energies. Depending on the processing parameters and examined polymers either hydrophobic or hydrophilic surfaces can be increased. The water contact angle of polydimethylsiloxane (PDMS) for example can be increased from 113° to approx. 150° so that the surface exhibits the so called lotus effect. The laser generated micro patterns reveal influence on cell density and cell distribution which can be used for cell guidance. Results for cell growing experiments are shown for different polymers

    Тепловая экономичность привода питательных насосов электростанций

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    In the production of micro devices the surface properties become more and more important for chemistry, biotechnology and medical technology with respect to wetting properties and chemical composition of the surface. Typical applications are implants as well as micro fluidic systems or miniaturized devices for DNA- and proteome analysis (biochips). In this paper newly designed laser technologies based on UV-laser treatment of polymers for surface processing are described to manipulate wetting properties, cell growth and immobilization of functional molecules with high spatial resolution. Depending on the processing parameters and used polymers either hydrophobic or hydrophilic properties can be enhanced (i.e. laser induced lotus/anti-lotus effect). Enhanced roughness and changes of the chemical composition have also influence on cell growth on polymer surfaces. Thus guiding aids for cells e.g. on medical implants can be generated by laser irradiation. Due to photo oxidation processes while UV-treatment in air, functional groups are created that are suited for covalent bonding of (bio)moelcules onto the surfaces. A second process for the locally selective immobilization of anchor molecules based on azide functionalized templates suitable for further modification steps is presented by means of irradiating polymers under solutions of these linkers

    Использование аналитики при создании бренда территории

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    Рассматриваются компоненты брендинга и бренда территории, раскрываются возможности использования аналитики при его создании и продвижении. Под аналитикой понимается обширное использование данных, статистического и количественного анализа, описательных и прогнозных моделей для принятия решений и действий, на основе реальных фактов. Делается вывод о том, что аналитика является наиболее эффективным механизмом при создании и продвижении бренда территории

    Development of a microreactor for solid phase synthesis

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    Laser micromanufacturing is well suited for the fabrication of microreaction systems. The use of high performance polymers in combination with microstructuration and microjoining technologies allows us to develop sealed microreaction systems. These are suited for organic synthesis even with aggressive reagents and under inert atmospheres. The microreaction system presented in this paper will enable us to perform combinatorial solid phase chemistry very efficiently. The most striking novelty of our microreactor matrix is the mixing of the reaction vessels by means of an oscillating membrane. That generates turbulence in the above suspension of a polymer resin. The addition of reagents and the work up / washing of the resin will be extremely fast and gentle

    Nanoscale biofunctionalization of polymer surfaces by laser treatment for controlled cellular differentiation

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    In this chapter we will discuss how nanostructures can interact with stem cells. After an introduction regarding the basic concepts of stem cells, their properties, and their uses in the medical field, we will then examine how stem cells can recognize physical forces and how this can be reproduced in vitro using materials produced in micro-and nanofabrication processes. Afterwards we will describe the principles and applications of a novel direct laser ablation technique, multibeam interference, and how patterns produced with such a method can be employed in stem cell research

    К вопросу о радиолокационном методе исследования метеоров

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    Das Potential der Laserstrahlung als Werkzeug zur Herstellung von Mikroreaktoren wurde anhand von Demonstratoren und Mikrostrukturen aus verschiedenen Polymeren und Gläsern demonstriert. Mit gepulster UV- Excimerlaserstrahlung (Wellenlängen 193 nm und 248 nm) wurden Mikrokanäle, Mikrobohrungen, Mikronäpfchen und Reaktionsvolumina im Maskenprojektionsverfahren hergestellt. Die Strukturgrößen liegen im Bereich 50-7000 mu m bei Strukturauflösungen < 10 mu m. Die Herstellungsdauer der Demonstratoren liegt im Bereich < 1 h, so daß dieses flexible Herstellungsverfahren insbesondere zur Prototypenherstellung - und zur Klein- und Mittelserienproduktion geeignet ist. Mikrostrukturen in den Standard- und Hochleistungspolymeren wie PC und PEEK sowie in Kalk-Natron-Silikatglas wurden beispielhaft für eine große Auswahl an strukturierbaren Werkstoffen dargestellt. Prozeßbedingte Ablagerungen (SchmeIze und Debris), die während des vorwiegend fotochemischen Matenialabtrags der Polymere auf der Oberfläche entstehen und die enters beeinflußen, werden durch ein Reinigungsverfahren mit Isopropanol nahezu vollständig entfernt. Zur Reinigung der Oberfläche beim fotothermischen Materialabtrag von Glas müssen die prozeßbedingten Ablagerungen während des Materialabtrags mit einer reaktiven F2/He-Prozeßgasatmosphäre modifiziert werden. Physikalische und chemische Wechselwirkungsprozesse von Schmelze und Debris mit dem Prozeßgas bewirken eine Reduzierung der Ablagerungen durch ein Reingungsverfahren mit Mucasol im Ultraschallbad auf eine Dicke < 20 nm. Die so entstehenden, planaren und mikrostrukturierten Werkstückoberflächen sind zur Herstellung geschlossener Mikroreaktoren durch anschließendes Fügen mit einem planaren Deckel geeignet

    Cyclization of Vinyl and Aryl Azides into Pyrroles, Indoles, Carbazoles, and Related Fused Pyrroles

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