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131.
Lothar Koschmieder 《Acta Mathematica》1947,79(1):241-254
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Novel Osmium‐based Coordination Complexes as Photosensitizers for Panchromatic Photodynamic Therapy
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Savo Lazic Pavel Kaspler Ge Shi Susan Monro Tariq Sainuddin Sarah Forward Kamola Kasimova Robie Hennigar Arkady Mandel Sherri McFarland Lothar Lilge 《Photochemistry and photobiology》2017,93(5):1248-1258
Cancer remains a major global malaise requiring the advent of new, efficient and low‐cost treatments. Photodynamic therapy, which combines a photosensitizer and photons to produce cytotoxic reactive oxygen species, has been established as an effective cancer treatment but has yet to become mainstream. One of the main limitations has been the paucity of photosensitizers that are effective over a wide range of wavelengths, can exert their cytotoxic effects in hypoxia, are easily synthesized and produce few if any side effects. To address these shortfalls, three new osmium‐based photosensitizers (TLD1822, TLD1824 and TLD1829) were synthesized and their photophysical and photobiological attributes determined. These photosensitizers are panchromatic (i.e. black absorbers), activatable from 200 to 900 nm and have strong resistance to photobleaching. In vitro studies show photodynamic therapy efficacy with both red and near‐infrared light in normoxic and hypoxic conditions, which translated to good in vivo efficacy of TLD1829 in a subcutaneous murine colon cancer model. 相似文献
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Prof. Dr. Shangfeng Yang Lin Zhang Wenfeng Zhang Prof. Dr. Lothar Dunsch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(41):12398-12405
Using guanidinium salts 1 and 2 as the new nitrogen sources, metal nitride clusterfullerenes (NCFs) based on a variety of metals (Dy, Sc, Y, Gd, Lu, and mixed metals Sc/Dy, Sc/Gd, Sc/Lu, and Lu/Ce) have been synthesized based on a new “selective organic solid” (SOS) route. The synthesis of Dy‐NCFs by using Dy/ 1 was studied in detail, and the optimum molar ratio of 1 /Dy/C has been determined to be 2.5:1:10. For several representative metals such as Sc, Y, Gd, Dy, and Sc/Dy, we quantitatively compared the yield of M3N@C80 synthesized by the SOS route with the reported “reactive gas atmosphere” route, thereby indicating that the yield of M3N@C80 by using 1 could be comparable to that obtained by the reactive gas atmosphere route. Three other nitrogen sources ( 3 – 5 ) were also studied for comparison, which were mixed with Dy metal but did not result in the formation of Dy‐NCF. A possible reaction scheme for the solid‐state reaction of 1 , metal, and graphite is proposed. The SOS route appears to be a general route for the synthesis of NCFs that promises both high selectivity of NCFs and high reproducibility of the fullerene yield. Another advantages of the SOS route compared to the reported “trimetallic nitride template” (TNT) process and the reactive gas atmosphere route is that no additional heating pretreatment is needed, thus simplifying the procedure and being much more facile. 相似文献
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Rodrigo Santos Rui M. Almeida Lothar Wondraczek 《Journal of solid state chemistry》2010,183(1):128-2701
Niobium germanosilicate glasses are potential candidates for the fabrication of transparent glass ceramics with interesting non-linear optical properties. A series of glasses in the (Ge,Si)O2-Nb2O5-K2O system were prepared by melting and casting and their characteristic temperatures were determined by differential thermal analysis. Progressive replacement of GeO2 by SiO2 improved the thermal stability of the glasses. Depending on the composition and the crystallization heat-treatment, different nanocrystalline phases—KNbSi2O7, K3Nb3Si2O13 and K3.8Nb5Ge3O20.4 could be obtained. The identification and characterization of these phases were performed by X-ray diffraction and Raman spectroscopy.The 40 GeO2-10 SiO2-25 Nb2O5-25 K2O (mol%) composition presented the higher ability for volume crystallization and its nucleation temperature was determined by the Marotta's method. An activation energy for crystal growth of ∼529 kJ/mol and a nucleation rate of 9.7×1018 m−3 s−1 was obtained, for this composition. Transparent glass ceramics with a crystalline volume fraction of ∼57% were obtained after a 2 h heat-treatment at the nucleation temperature, with crystallite sizes of ∼20 nm as determined by transmission electron microscopy. 相似文献
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Sebastian Gatz Helge Hannebauer Rene Hesse Florian Werner Arne Schmidt Thorsten Dullweber Jan Schmidt Karsten Bothe Rolf Brendel 《固体物理学:研究快报》2011,5(4):147-149
We demonstrate industrially feasible large‐area solar cells with passivated homogeneous emitter and rear achieving energy conversion efficiencies of up to 19.4% on 125 × 125 mm2 p‐type 2–3 Ω cm boron‐doped Czochralski silicon wafers. Front and rear metal contacts are fabricated by screen‐printing of silver and aluminum paste and firing in a conventional belt furnace. We implement two different dielectric rear surface passivation stacks: (i) a thermally grown silicon dioxide/silicon nitride stack and (ii) an atomic‐layer‐deposited aluminum oxide/silicon nitride stack. The dielectrics at the rear result in a decreased surface recombination velocity of Srear = 70 cm/s and 80 cm/s, and an increased internal IR reflectance of up to 91% corresponding to an improved Jsc of up to 38.9 mA/cm2 and Voc of up to 664 mV. We observe an increase in cell efficiency of 0.8% absolute for the cells compared to 18.6% efficient reference solar cells featuring a full‐area aluminum back surface field. To our knowledge, the energy conversion efficiency of 19.4% is the best value reported so far for large area screen‐printed solar cells. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献