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271.
272.
Sanchez Sanchez M Girgsdies F Jastak M Kube P Schlögl R Trunschke A 《Angewandte Chemie (International ed. in English)》2012,51(29):7194-7197
In?situ Raman spectroscopy allows insight into molecular processes under hydrothermal conditions during synthesis of complex nanostructured MoVTeNb oxides (see picture: Nb?yellow, Mo?blue, V/Mo?pale blue, Te?red). Based on the knowledge acquired, the synthesis can be more efficiently directed towards the desired product with improved functionality. 相似文献
273.
Katarzyna Niemiec Magdalena Kaczmarska Mateusz Buczkowski Maria Fornal W?adys?aw Pohorecki Krzysztof Matlak Józef Korecki Tomasz Grodzicki Kvetoslava Burda 《Hyperfine Interactions》2012,206(1-3):95-100
We studied radiation effects on the stability of various states of hemoglobin (Hb) in red blood cells (RBC) irradiated with a very low dose of neutron rays, 50?μGy. We investigated RBCs isolated from blood of healthy donors. M?ssbauer spectroscopy was applied to monitor different forms of Hb. Our results show, for the first time, that oxyhemoglobin (OxyHb) and deoxyhemoglobin (DeoxyHb) are two Hb forms sensitive to such a low neutron radiation. Both Hbs change into a new Hb form (Hbirr). Additionally, OxyHb transfers into HbOH/H2O, which under our experimental conditions is resistant to the action of neutron rays. 相似文献
274.
A discrete–continuous problem of non-preemptive task scheduling on identical parallel processors is considered. Tasks are described by means of a dynamic model, in which the speed of the task performance depends on the amount of a single continuously divisible renewable resource allotted to this task over time. An upper bound on the completion time of all the tasks is given. The criterion is to minimize the maximum resource consumption at each time instant, i.e., the resource level. This problem has been observed in many industrial applications, where a continuously divisible resource such as gas, fuel, electric, hydraulic or pneumatic power, etc., has to be distributed among the processing units over time, and it affects their productivity. The problem consists of two interrelated subproblems: task sequencing on processors (discrete subproblem) and resource allocation among the tasks (continuous subproblem). An optimal resource allocation algorithm for a given sequence of tasks is presented and computationally tested. Furthermore, approximation algorithms are proposed, and their theoretical and experimental worst-case performances are analyzed. Computer experiments confirmed the efficiency of all the algorithms. 相似文献
275.
We prove the existence of boundary limits of ratios of positive harmonic functions for a wide class of Markov processes with jumps and irregular (possibly disconnected) domains of harmonicity, in the context of general metric measure spaces. As a corollary, we prove the uniqueness of the Martin kernel at each boundary point, that is, we identify the Martin boundary with the topological boundary. We also prove a Martin representation theorem for harmonic functions. Examples covered by our results include: strictly stable Lévy processes in R d with positive continuous density of the Lévy measure; stable-like processes in R d and in domains; and stable-like subordinate diffusions in metric measure spaces. 相似文献
276.
Preparation and properties of textile materials modified with triclosan‐loaded polylactide microparticles 下载免费PDF全文
Agnieszka Karaszewska Irena Kamińska Magdalena Kiwała Mariusz Gadzinowski Mateusz Gosecki Stanislaw Slomkowski 《先进技术聚合物》2017,28(9):1185-1193
A convenient and simple method for preparation of commercial nonwovens with antimicrobial properties was elaborated. The process consists in preparation of poly(l ‐lactide) microspheres (from poly(l ‐lactide) with M n = 10,560 and M w /M n = 1.39) containing triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy) phenol) and loading them onto the nonwovens. The microspheres were prepared by spray drying (D n = 3.91 μm, D w /D n = 2.43) and oil‐in‐water emulsification‐solvent evaporation method (D n = 5.84 μm, D w /D n = 1.25). Content of triclosan in microspheres ranged from 4.65 to 4.95 wt%. The antibacterial nonwovens were prepared by padding of the fibers with the microspheres using the microsphere suspension. The resulting antibacterial nonwovens were examined using inhibition zone measurement method. Inhibition zones from 4 to 9 mm indicated that the modified nonwovens had antibacterial properties against Gram (+)—Staphylococcus aureus and Gram (?)—Klebsiella pneumoniae . Nonwovens were conditioned up to 12 months at relative humidity <5%, 50%, and 100% in desiccators and up to 6 months air‐conditioning system at relative humidity = 65%. Antimicrobial activity of the modified nonwovens was examined as a function of time and air humidity. Time of conditioning has strong influence on antibacterial activity, whereas the impact of the air humidity was negligible. All nonwovens had antibacterial properties even after 12 months of conditioning. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
277.
Liverwort endophytes could be a source of new biologically active substances, especially when these spore-forming plants are known to produce compounds that are not found in other living organisms. Despite the significant development of plant endophytes research, there are only a few studies describing liverwort endophytic microorganisms and their metabolites. In the presented study, the analysis of the volatile compounds obtained from thallose liverwort species, Marchantia polymorpha L., and its endophytes was carried out. For this purpose, non-polar extracts of plant material and symbiotic microorganisms were obtained. The extracts were analyzed using gas chromatography coupled to mass spectrometry. Compounds with the structure of diketopiperazine in the endophyte extract were identified. Liverwort volatile extract was a rich source of cuparane-, chamigrane-, acorane-, and thujopsane-type sesquiterpenoids. The cytotoxicity of ethyl acetate extracts from endophytic microorganisms was evaluated on a panel of cancer (FaDu, HeLa, and SCC-25) cell lines and normal (VERO), and revealed significant anticancer potential towards hypopharyngeal squamous cell carcinoma and cervical adenocarcinoma. 相似文献
278.
We study the existence of constrained fixed points of contractions in arbitrary complete metric spaces from a global and local point of view. In particular, we provide generalizations of results due to Lim, Downing and Kirk and others. Some aspects of the topological transversality in the spirit of Frigon and Granas of contractions under constraints are also considered. 相似文献
279.
Mateusz Kwaśnicki 《Semigroup Forum》2009,79(1):183-192
We prove that the eigenvalues of the semigroup of the Cauchy process killed upon exiting the interval have at most double
multiplicity. In passing we obtain an interesting identity involving Fourier transform.
The research was supported by KBN grant 1 P03A 020 28. 相似文献
280.
Krzysztof Bogdan Tadeusz Kulczycki Mateusz Kwaśnicki 《Probability Theory and Related Fields》2008,140(3-4):345-381
We prove a uniform boundary Harnack inequality for nonnegative harmonic functions of the fractional Laplacian on arbitrary
open set D. This yields a unique representation of such functions as integrals against measures on D
c
∪ {∞} satisfying an integrability condition. The corresponding Martin boundary of D is a subset of the Euclidean boundary determined by an integral test.
K. Bogdan was supported by KBN grant 1 P03A 026 29 and RTN contract HPRN-CT-2001-00273-HARP. T. Kulczycki was supported by
KBN grant 1 P03A 020 28 and RTN contract HPRN-CT-2001-00273-HARP. M. Kwaśnicki was supported by KBN grant 1 P03A 020 28 and
RTN contractHPRN-CT-2001-00273-HARP. 相似文献