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61.
Lucian Gabriel Bahrin Alina Nicolescu Sergiu Shova Narcisa Laura Marangoci Lucian Mihail Birsa Laura Gabriela Sarbu 《Molecules (Basel, Switzerland)》2021,26(19)
Mesitylene was used as a core in seven new tritopic nitrogen containing linkers. Three of the linkers, each containing three nitrile groups, were obtained through Suzuki, Sonogashira and Heck-type coupling reactions. Next, these were converted to tetrazol-5-yl moieties by the cycloaddition of sodium azide to the nitrile functionalities. The last linker, containing three 1,2,3-triazol-4-yl moieties, was synthesized by the Huisgen cycloaddition of phenyl azide to the corresponding alkyne. The latter was obtained via a Corey–Fuchs reaction sequence from the previously reported formyl derivative. As the proof of concept for their potential in MOF design, one of the nitriles was used to build an Ag-based network. 相似文献
62.
63.
64.
This paper investigates the tightness property of the capacityinduced by the reduction operator with respect to the resolventof a right Markov process. Tightness is verified in two particularsituations: under the weak duality hypothesis,and if a substitute for the axiom of polarity for thedual theory holds. In the second context, the quasi-continuityproperty for the excessive functions is derived. These are extensionsand improvements of results of Lyons and Röckner, Ma andRöckner, Le Jan, and Fitzsimmons, mainly obtained in thecontext of Dirichlet forms. 2000 Mathematics Subject Classification31C25, 60J45 (primary), 31C15, 60J40 (secondary). 相似文献
65.
Kontsevich’s formality theorem and the consequent star-product formula rely on the construction of an L
∞-morphism between the DGLA of polyvector fields and the DGLA of polydifferential operators. This construction uses a version
of graphical calculus. In this article we present the details of this graphical calculus with emphasis on its algebraic features.
It is a morphism of differential graded Lie algebras between the Kontsevich DGLA of admissible graphs and the Chevalley–Eilenberg
DGLA of linear homomorphisms between polyvector fields and polydifferential operators. Kontsevich’s proof of the formality
morphism is reexamined in this light and an algebraic framework for discussing the tree-level reduction of Kontsevich’s star-product
is described.
Mathematics Subject Classifications (2000): 53D55, secondary 18G55 相似文献
66.
Suppose that U is the resolvent of a Borel right process on a Lusin space X. If is a U-excessive measure on X then we show by analytical methods that for every U-excessive measure with the Radon–Nikodym derivative d/d possesses a finely continuous version. (Fitzsimmons and Fitzsimmons and Getoor gave a probabilistic approach for this result.) We extend essentially a technique initiated by Mokobodzki and deepened by Feyel. The result allows us to establish a Revuz type formula involving the fine versions, and to study the Revuz correspondence between the -finite measures charging no set that is both -polar and -negligible (U being the potential component of ) and the strongly supermedian kernels on X. This is an analytic version of a result of Azéma, Fitzsimmons and Dellacherie, Maisonneuve and Meyer, in terms of additive functionals or homogeneous random measures. Finally we give an application to the context of the semi-Dirichlet forms, covering a recent result of Fitzsimmons. 相似文献
67.
We consider a proper submarkovian resolvent of kernels on a Lusin measurable space and a given excessive measure ξ. With
every quasi bounded excessive function we associate an excessive kernel and the corresponding Revuz measure. Every finite
measure charging no ξ–polar set is such a Revuz measure, provided the hypothesis (B) of Hunt holds. Under a weak duality hypothesis,
we prove the Revuz formula and characterize the quasi boundedness and the regularity in terms of Revuz measures. We improve
results of Azéma [2] and Getoor and Sharpe [20] for the natural additive functionals of a Borel right process.
Received: 30 April 1997 / Revised version: 17 September 1999 /?Published online: 11 April 2000 相似文献
68.
Gabriela Buda Adrian Samuila Salah Atroune Mihai Bilici Lucien Dascalescu 《Journal of Electrostatics》2013,71(3):407-412
Identification of the optimal operating conditions is a critical issue for the industrial application of tribocharging techniques. The aim of this paper is to formulate a set of recommendations regarding the choice of tray length, vibration amplitude and material feed-rate values for a vibratory-type tribocharger. The study was carried out on a laboratory vibratory feeder with granular plastics originating from waste electrical and electronic equipment. Several one-factor-at-a-time experiments followed by a composite factorial experiment were performed based on a two-step strategy: 1) identifying the domain of variation of the controlled variables; 2) finding the best choice of the set point. 相似文献
69.
Carmen I. Fort Mihai M. Rusu Liviu C. Cotet Adriana Vulpoi Ileana Florea Sandrine Tuseau-Nenez Monica Baia Mihaela Baibarac Lucian Baia 《Molecules (Basel, Switzerland)》2021,26(1)
Multifunctional Bi- and Fe-modified carbon xerogel composites (CXBiFe), with different Fe concentrations, were obtained by a resorcinol–formaldehyde sol–gel method, followed by drying in ambient conditions and pyrolysis treatment. The morphological and structural characterization performed by X-ray diffraction (XRD), Raman spectroscopy, N2 adsorption/desorption porosimetry, scanning electron microscopy (SEM) and scanning/transmission electron microscopy (STEM) analyses, indicates the formation of carbon-based nanocomposites with integrated Bi and Fe oxide nanoparticles. At higher Fe concentrations, Bi-Fe-O interactions lead to the formation of hybrid nanostructures and off-stoichiometric Bi2Fe4O9 mullite-like structures together with an excess of iron oxide nanoparticles. To examine the effect of the Fe content on the electrochemical performance of the CXBiFe composites, the obtained powders were initially dispersed in a chitosan solution and applied on the surface of glassy carbon electrodes. Then, the multifunctional character of the CXBiFe systems is assessed by involving the obtained modified electrodes for the detection of different analytes, such as biomarkers (hydrogen peroxide) and heavy metal ions (i.e., Pb2+). The achieved results indicate a drop in the detection limit for H2O2 as Fe content increases. Even though the current results suggest that the surface modifications of the Bi phase with Fe and O impurities lower Pb2+ detection efficiencies, Pb2+ sensing well below the admitted concentrations for drinkable water is also noticed. 相似文献
70.
Jan Weis Lucian Covaciu Sten Rubertsson Mats Allers Anders Lunderquist Francisco Ortiz-Nieto Håkan Ahlström 《Magnetic resonance imaging》2012
Decrease of the human brain temperature was induced by intranasal cooling. The main purpose of this study was to compare the two magnetic resonance methods for monitoring brain temperature changes during cooling: phase-difference and magnetic resonance spectroscopic imaging (MRSI) with high spatial resolution. Ten healthy volunteers were measured. Selective brain cooling was performed through nasal cavities using saline-cooled balloon catheters. MRSI was based on a radiofrequency spoiled gradient echo sequence. The spectral information was encoded by incrementing the echo time of the subsequent eight image records. Reconstructed voxel size was 1×1×5 mm3. Relative brain temperature was computed from the positions of water spectral lines. Phase maps were obtained from the first image record of the MRSI sequence. Mild hypothermia was achieved in 15–20 min. Mean brain temperature reduction varied in the interval <−3.0; − 0.6>°C and <−2.7; − 0.7>°C as measured by the MRSI and phase-difference methods, respectively. Very good correlation was found in all locations between the temperatures measured by both techniques except in the frontal lobe. Measurements in the transversal slices were more robust to the movement artifacts than those in the sagittal planes. Good agreement was found between the MRSI and phase-difference techniques. 相似文献