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Iridium Corroles Exhibit Weak Near-Infrared Phosphorescence but Efficiently Sensitize Singlet Oxygen Formation.
Six-coordinate iridium(III) triarylcorrole derivatives, Ir[TpXPC)]L2, where TpXPC = tris(para-X-phenyl)corrole (X = CF3, H, Me, and OCH3) and L = pyridine (py), trimethylamine (tma), isoquinoline (isoq), 4-dimethylaminopyridine (dmap), and 4-picolinic acid (4pa), have been examined, with a view to identifying axial ligands most conducive to near-infrared phosphorescence. Disappointingly, the phosphorescence quantum yield invariably turned out to be very low, about 0.02 - 0.04% at ambient temperature, with about a two-fold increase at 77 K. Phosphorescence decay times were found to be around ~5 µs at 295 K and ~10 µs at 77 K. Fortunately, two of the Ir[TpCF3PC)]L2 derivatives, which were tested for their ability to sensitize singlet oxygen formation, were found to do so efficiently with quantum yields Φ(1O2) = 0.71 and 0.38 for L = py and 4pa, respectively. Iridium corroles thus may hold promise as photosensitizers in photodynamic therapy (PDT). The possibility of varying the axial ligand and of attaching biotargeting groups at the axial positions makes iridium corroles particularly exciting as PDT drug candidates
Mn4+-doped magnesium titanate : a promising phosphor for self-referenced optical temperature sensing
Phosphors based on magnesium titanate activated with Mn4+ ions are of great interest because, when excited with blue light, they display a strong red-emitting luminescence. They are characterized by a luminescence decay which is strongly temperature dependent in the range from -50°C to 150°C, making these materials very promising for temperature sensing in the biochemical field. In this work, the optical and thermal properties of the luminescence of Mg2TiO4 are investigated for different Mn4+ doping concentrations. The potential of this material for temperature sensing is demonstrated by fabricating a fiber optic temperature microsensor and by comparing its performance against a standard resistance thermometer. The response of the fiber optic sensor is exceptionally fast, with a response time below 1 s in the liquid phase and below 1.1 s in the gas phase
La naissance de la philosophie profonde à partir de l’esprit onto-design
The paper outlines the basic principles of Deep Philosophy – one of the areas of modern philosophical practice. The author considers these principles in the context of onto-designing, a phenomenological model developed by Yuri Mikhailovich Reznik. The author gives a detailed explanation of the main concepts of Deep Philosophy, such as deep dimension, contemplation, personality, resonance, etc. from the position of correlation of the ontic and ontological, the world in-itself and the world for-itself. In addition, the author shares the experience of the philosophical retreat of Deep Philosophy, which took place in September 2019.Rad ocrtava temeljne principe »dubinske filozofije« – jednog područja suvremene filozofijske prakse. Autor te principe razmatra u kontekstu »onto-dizajniranja«, fenomenološke metode koju je razvio Yuri Mikhailovich Reznik. Daje se detaljno objašnjenje glavnih pojmova dubinske filozofije, kao što su dubinska dimenzija, kontemplacija, osobnost, rezonancija itd., iz pozicije korelacije ontičkog i ontološkog, svijeta u-sebi i svijeta za-sebe. Dodatno, dijeli se iskustvo filozofijskog povlačenja u dubinskoj filozofiji, koje se odvilo u rujnu 2019. godine.Die Arbeit umreißt die Grundprinzipien der „Tiefenphilosophie“ – eines Bereichs der zeitgenössischen philosophischen Praxis. Der Autor zieht diese Prinzipien im Kontext des „Onto-Designs“ in Erwägung, einer phänomenologischen Methode, die von Y. M. Reznik entwickelt wurde. Es wird eine detaillierte Erklärung der Hauptbegriffe der Tiefenphilosophie wie Tiefendimension, Kontemplation, Persönlichkeit, Resonanz usw. gegeben, und zwar von der Position der Korrelation des Ontischen und Ontologischen aus, bzw. der Welt in-sich und der Welt für-sich. Darüber hinaus wird die Erfahrung des philosophischen Rückzugs in der Tiefenphilosophie, der im September 2019 stattfand, geteilt.Ce travail présente les principes fondamentaux de la « philosophie profonde » – un domaine de la philosophie pratique contemporaine. L’auteur analyse ces principes dans le contexte de « l’onto-design », une méthode phénoménologique développé par Y. M. Reznik. Les explications détaillées des concepts de la philosophie profonde sont énoncées, tels que la dimension profonde, la contemplation, la personnalité, la résonnance, etc., à partir du point de vue de corrélation de l’ontique et de l’ontologique, du monde en-soi et du monde pour-soi. De plus, l’expérience du retrait de la philosophie dans la philosophie profonde qui s’est déroulé en septembre 2019 sera évoquée
Stable optical oxygen sensing materials based on click-coupling of fluorinated platinum(II) and palladium(II) porphyrins—A convenient way to eliminate dye migration and leaching
AbstractNucleophilic substitution of the labile para-fluorine atoms of 2,3,4,5,6-pentafluorophenyl groups enables a click-based covalent linkage of an oxygen indicator (platinum(II) or palladium(II) 5,10,15,20-meso-tetrakis-(2,3,4,5,6-pentafluorophenyl)-porphyrin) to the sensor matrix. Copolymers of styrene and pentafluorostyrene are chosen as polymeric materials. Depending on the reaction conditions either soluble sensor materials or cross-linked microparticles are obtained. Additionally, we prepared Ormosil-based sensors with linked indicator, which showed very high sensitivity toward oxygen. The effect of covalent coupling on sensor characteristics, stability and photophysical properties is studied. It is demonstrated that leaching and migration of the dye are eliminated in the new materials but excellent photophysical properties of the indicators are preserved
Algorithm and Software for Operative Calculations of the Short Circuits Modes
Smart power grids provide efficient control of power flows or other grid variables, such as voltages or short circuit currents. Most essential the control has become, if the consumers are electrical systems of high power capacity. These systems are able to reconfigure the grid structure for emergency situations. The developed algorithm is intended for carrying out operational calculations of short-circuits modes in electrical grids of voltage 0,4kV to 220kV. In the calculation the following methods have been used: methods of node voltages, method of superposition and method of branch expansion to form the node voltage matrix according to the graphs theory. In the software the short circuit inflow from all electrical motors and nodes with generalized load is taken into account as opposed to other algorithms. The calculated circuit can have up to 700 nodes; there is ability to decrease number of branches and nodes and to form the calculative model of the grid part. Calculation algorithm of the short circuit currents is implemented as a sequence of software calculations. Software of systems and grids, in which short circuits are altered, allows carrying out operational calculations of the short circuit modes to adjust settings of relays protection devices, to check electrical equipment and to replace it, to choose optimal operational circuits. Actuality of the calculations is caused by need of the software implementation to maintain, upgrade and design the electrical grids of enterprises that have their own power plants
Technology of ultrasonic control of gas-shielded welding process
A new approach to implementation of electrode metal transfer control under MAG, MIG welding is suggested. The process ensures control of thermal and crystallization processes, stabilizes the time of electrode metal drop formation. The results of the research allow formulating the basic criteria of electrode metal transfer control via ultrasonic exposure, determining the conditions of producing a more equilibrium structure of deposit metal
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