The INF Treaty of 1987

Der von Ronald Reagan und Michail Gorbatschow am 8. Dezember 1987 unterzeichnete »Intermediate-Range Nuclear Forces Treaty«, kurz INF-Vertrag, stellte einen Meilenstein der nuklearen Abrüstungsverhandlungen zwischen den Vereinigten Staaten von Amerika und der Sowjetunion dar. Im Jahr 2019 wurde er von Russland und den USA gekündigt. Der englischsprachige Band untersucht die Vorgeschichte des Abkommens, dessen Implementierung und Folgen sowohl in den beiden Supermächten als auch in den mit ihnen verbündeten Staaten. Er ist damit die erste umfassende Darstellung eines der wichtigsten Abrüstungsabkommen der jüngsten Zeit

Bodegradable polymeric system releasing radiosensitizer - the in vitro studies

W pracy przedstawiono wyniki badań uwalniania radiouczulacza metronidazolu z jednowarstwowych oraz trójwarstwowych matryc kopolimeru glkolidu z laktydem do sztucznego płynu mózgowo rdzeniowego ACFs. Przeprowadzono analizę mikrostruktury łańcuchów polimerowych w oparciu o spektroskopię magnetycznego rezonansu jądrowego. Badanie uwalniania leku prowadzono w systemie dynamicznym z regularną wymianą buforu we fiolkach poddanych wytrząsaniu. Ekstrakty analizowano metodą spektrometrii UV-VIS. Równolegle prowadzono badania degradacji matryc z lekiem pod kątem oceny zmian w mikrostrukturze łańcucha polimerowego. Badania wykazały znacznie szybszą degradację matryc wykonanych z kopolimeru glikolidu z D,L-laktydem w porównaniu z matrycami z kopolimeru glikolidu z L-laktydem. Ponadto wykazano że opłaszczenie matrycy zawierającej lek polimerem bez leku (matryce trójwarstwowe) zapobiega nagłemu wyrzutowi leku z powierzchni w pierwszych dniach uwalniania.In this paper the results of radiosensitizer metronidazole release investigation from mono- and triple-layered copolymeric matrices in artificial cerebro- spinal fluid solution (ACFs) are presented. The analysis of polymeric chain microstructure by the NMR has been conducted. Drug release study was performed in the dynamic system with regular buffer exchange in constantly stirred glass ampoules. The extracts were analyzed by the UV-VIS spectrometry. Drug carrying matrices degradation research were conducted to evaluate possible changes in polymeric chain microstructure. The results showed that matrices containing poly(glycolide-co-D,L-lactide) demonstrate higher degradation rate than matrices containing poly(glycolide-co-L-lactide). It has been proved that drug carriers coated with drug-free polymer (triplelayered matrices) prevents from burst effect

Stability of Diodes with Poly(3-hexylthiophene) and Polyazomethines Thin Organic Layer

Herein we report results of studies on stability of diodes based on organic semiconductors such as poly (3-hexylthiophene) (P3HT) and soluble derivative of polyazomethine poly(1,4-(2,5-bisoctyloxy phenylenemethylidynenitrilo)-1,4-phenylenenitrilomethylidyne), (BOO-PPI). Both polymers were deposited on glass/ITO substrate with or without covering with blocking layer: poly(3,4-ethylenedioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) and finished with Al back electrode. Prepared devices were studied by monitoring their electrical conductivity under nitrogen atmosphere and ambient air conditions. Under nitrogen atmosphere a marked influence of presence of the blocking layer on the diodes electrical conductivity was revealed. The P3HT diodes prepared without PEDOT:PSS thin film shown quick degradation, whereas presence of these layers stabilizes electrical conductivity in these devices. Inversely, the PPI based diodes without the PEDOT:PSS revealed stable conducting properties, while corresponding diodes with PEDOT:PSS layer showed degradation traces of their conducting properties

Optical Properties of Semiladder Polymer Foils

Optical transmission of amorphous polyimidazopyrrolone foils (pyrrons) were investigated in the spectral range 200-3300nm. The investigated materials exhibit a high transmission level (up to 85%) in a wide range from about 500 to 2750nm. The short wavelength edge of transmission depends on the pyrron chemical structure being different for ether-, amide- and ester bridges. When analysing the experimental data, we applied the approach used for amorphous materials in order to determine the electronic structure parameters which may be related to the influence of polyimidazopyrrolone bridge structure and structural disorder on the optical properties and probable electronic transitions

Influence of Rare Earth Ions on the Optical Properties of Tellurite Glass

The goal of this work was to investigate the influence of rare-earth ions such as $Nd^{3+}$ and $Er^{3+}$ on the optical properties of tellurite glass of the $TeO_2-WO_3-PbO-La_2O_3$ system. The optical studies of the glasses comprised spectrophotometry (reflectance and transmittance) and spectroscopic ellipsometry. The spectrophotometric measurements yield a number of narrow absorption bands which correspond to characteristic transitions between the ground- and consecutive excited states of rare-earth ions. From ellipsometric studies, in turn, the dispersion of the refraction coefficient has been obtained which appears to be practically the same for the tellurite glass matrix and the matrix doped with $Nd^{3+}$ and $Er^{3+}$ ions

Stability of Diodes with Poly(3-hexylthiophene) and Polyazomethines Thin Organic Layer

Herein we report results of studies on stability of diodes based on organic semiconductors such as poly (3-hexylthiophene) (P3HT) and soluble derivative of polyazomethine poly(1,4-(2,5-bisoctyloxy phenylenemethylidynenitrilo)-1,4-phenylenenitrilomethylidyne), (BOO-PPI). Both polymers were deposited on glass/ITO substrate with or without covering with blocking layer: poly(3,4-ethylenedioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) and finished with Al back electrode. Prepared devices were studied by monitoring their electrical conductivity under nitrogen atmosphere and ambient air conditions. Under nitrogen atmosphere a marked influence of presence of the blocking layer on the diodes electrical conductivity was revealed. The P3HT diodes prepared without PEDOT:PSS thin film shown quick degradation, whereas presence of these layers stabilizes electrical conductivity in these devices. Inversely, the PPI based diodes without the PEDOT:PSS revealed stable conducting properties, while corresponding diodes with PEDOT:PSS layer showed degradation traces of their conducting properties

Spectroscopic Properties of Pr3+Pr^{3+} Ion in Various Tellurite Glasses

The goal of this work was to investigate the spectroscopic properties of $Pr^{3+}$ ions (of a comparable concentration of the order of 0.2 mol/dm³) embedded in the tellurite glass matrix, i.e. $TeO_2-WO_3-PbO$ modified with lanthanum and lutetium oxides. The difference is that the last components of both glasses provide ions which are optically inactive within the 4f shell, since this shell is completely empty for $La^{3+}$ ion and completely filled for $Lu^{3+}$ ion. The absorption and fluorescence spectra of $Pr^{3+}$ doped in tellurite glass has been recorded and analyzed in terms of the Judd-Ofelt theory. The studies of the glasses comprised ellipsometric, spectrophotometric and photoluminescence measurements. The ellipsometric studies yield the refraction index dispersion which appears to be quite similar for all the studied glasses. From the spectrophotometric measurements, the absorption spectra have been obtained which, for $Pr^{3+}$-doped samples, have been analyzed in terms of the Judd-Ofelt theory. Finally, the photoluminescence studies demonstrate a clear visible emission from $\text{}^3P_0$ level to lower-lying states of $Pr^{3+}$ ion