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101.
Cristina Canal Freddy Gaboriau Andre Ricard Miran Mozetic Uros Cvelbar Aleksander Drenik 《Plasma Chemistry and Plasma Processing》2007,27(4):404-413
Density of neutral oxygen atoms in the ground state has been measured during treatment of wool fabric samples. Samples were
placed in an afterglow reactor with a volume of about 5 l, which was pumped with a two stage rotary pump with the nominal
pumping speed of 28 m3/h. The source of the oxygen atoms was a microwave discharge operating in the surfatron mode at 2.45 GHz and adjustable output
power up to 300 W. The density of O-atoms in the afterglow chamber was measured with a fiber-optics catalytic probe. For the
empty reactor, the O density depended on discharge parameters and was between 0.8 and 2.8 × 1021 m−3 at 40 and 50 Pa respectively. During the treatment of wool, the O density depended largely on the exposure time. For untreated
samples, the O density was below the detection limit of the probe, while prolonged treatment allowed for recovering the O
density. The recovery always occurred after having submitted wool samples to the dose of the order of 1023 atoms/m2. The results were explained by oxidation of the thin lipid layer on the surface of the wool fibres. 相似文献
102.
103.
Aleksandra Kawczyk-Krupka Dorota Bartusik-Aebisher Wojciech Latos Grzegorz Cieślar Karolina Sieroń Sebastian Kwiatek Piotr Oleś Beata Kwiatek David Aebisher Magdalena Krupka Rafał Wiench Dariusz Skaba Marcin Olek Jacek Kasperski Zenon Czuba Aleksander Sieroń 《Photochemistry and photobiology》2020,96(3):539-549
The purpose of this review is to present an overview of the development of photodiagnostic and photodynamic therapy (PDD and PDT) techniques in Poland. The paper discusses the principles of PDD, including fluorescent techniques in determining precancerous conditions and cancers of the skin, digestive tract, bladder and respiratory tract. Methods of PDT of cancer will be discussed and the current state of knowledge as well as future trends in the development of photodynamic techniques will be presented, including the possibility of using photodynamic antimicrobial therapy. Research pioneers in photodynamic medicine such as Thomas Dougherty are an inspiration for the development of methods of PDD and PDT in our Clinic. The Center for Laser Diagnostics and Therapy in Bytom, Poland, promotes the propagation of PDD and PDT through the training of clinicians and raising awareness among students in training and the general public. Physicians at the Center are engaged in photomedical research aimed at clinical implementation and exploration of new avenues in photomedicine while optimizing existing modalities. The Center promotes dissemination of clinical results from a wide range of topics in PDD and PDT and serving as representative authorities of photodynamic medicine in Poland and Europe. 相似文献
104.
Matt Rammo Dr. Aleksander Trummal Dr. Merle Uudsemaa Juri Pahapill Katrin Petritsenko Dr. Meelis-Mait Sildoja Dr. Charles W. Stark Dr. Sigrid Selberg Prof. Ivo Leito Kirsti Palmi Dr. Jasper Adamson Prof. Aleksander Rebane 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(8):e202103707
Lipophilic fluorophores are widely implemented in nonlinear microscopy; however, few existing membrane-specific probes combine the high brightness of two-photon excited fluorescence (2PEF) with pH sensitivity. Herein we describe four novel two-photon excited fluorophores, based on a coumarin 151 core structure, where lipophilicity is induced by a covalently attached phosphazene moiety. Changing the environmental acidity using trifluoromethanesulfonic (triflic) acid leads to profound changes in the linear fluorescence and 2PEF characteristics, due to chromophores’ switching between neutral- and protonated forms. We characterize this dependence by measuring the two-photon absorption (2PA) spectra over the region λ2PA=550–1000 nm, observing 2PA cross sections of σ2PA=10–20 GM, with an associated 2PEF brightness of 10–13 GM, in neutral solutions of both acetonitrile and n-octanol. Although quantum chemical modelling and NMR measurements show that, at high chromophore concentrations, protonation may be accompanied by a dimerization process, these dimers likely do not form at the lower concentrations used in optical spectroscopy. 相似文献
105.
Demekhin Oleg D. Zagrebaev Aleksander D. Burov Oleg N. Kletskii Mikhail E. Pavlovich Natal’ya V. Bereznyak Elena A. Tsimbalistova Marina V. Kurbatov Sergey V. 《Chemistry of Heterocyclic Compounds》2019,55(11):1128-1130
Chemistry of Heterocyclic Compounds - A method for the synthesis of berberine 13-vinyl derivatives has been developed consisting of an initial reaction of triethyl orthoformate with CH acids in the... 相似文献
106.
Aleksander Drenik Alenka VeselArkadi Kreter Miran Mozeti? 《Applied Surface Science》2011,257(13):5820-5825
The probability of recombination of hydrogen atoms on surfaces of fine-grain graphite EK98 was investigated as a function of surface roughness. The source of hydrogen atoms used in this experiment was weakly ionised plasma created with an inductively coupled radiofrequency generator at pressures from 30 Pa to 175 Pa in hydrogen. Hydrogen atom density was measured by means of fibre optic catalytic probes. The recombination coefficient of the graphite samples was determined by observing their impact on the spatial distribution of the atom density in a closed side-arm of the reactor. Smith's diffusion model was used to calculate the values of the recombination coefficient. The measured recombination coefficient was found to increase much faster than the measured effective surface. This discrepancy is explained by the fact that on a surface which is not perfectly flat, there is a finite probability for multiple collisions. Impinging atoms collide more than once with the surface before they are reflected into the surface, which results in a larger probability of recombination. 相似文献
107.
Barbara Bartoś Barbara Filipowicz Monika Łyczko Aleksander Bilewicz 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):513-516
Dynamic adsorption of radiocesium on titanium ferrocyanide grains from reactor coolant simulating solution containing salts at moderate concentrations has been investigated. Effective decontamination of the neutral solutions has been achieved, in the amounts of a more than 20 thousand bed volumes. After adsorption the titanium ferrocyanide was transferred to titanates and calcined at 900 °C. The leaching test of the obtained lithium titanates indicates that the loaded adsorbent can serve as an effective primary barrier in nuclear waste repositories. 相似文献
108.
109.
In the first part of the paper we provide a construction of an abstract homotopy invariant detecting zeros of maps of the form −A+F where is a densely defined m-accretive operator in a Banach space E and is a tangent field defined on an open subset U of a neighborhood retract M being invariant with respect to the resolvents of A. The construction is performed under the assumption that resolvents of A are completely continuous. In the second part we derive index formulae for isolated zeros and apply them to show the existence of nontrivial positive steady state solutions for a class of nonlinear reaction-diffusion equations and equations with one-dimensional p-Laplacian with possibly non-positive perturbations as well as some controlled Neumann-like problems. 相似文献
110.
Every finite disconnected set P is determined (up to automorphism) by the family {P − {a}:a ∈ Max
P
}. 相似文献