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121.
Mazur Milan Valko Marian Rhodes Christopher J. 《Journal of Sol-Gel Science and Technology》2017,82(3):855-861
Journal of Sol-Gel Science and Technology - The influence of the hydration and drying process on the line shape and signal intensity of the electron paramagnetic resonance spectra recorded from... 相似文献
122.
Synthesis of a potential Src family SH2 domain inhibitor incorporating a 1,4-cis-enediol scaffold is reported. The synthetic route offers straightforward and highly selective access to the enediol and its associated chiral centers. Key steps include stereocontrolled syn-aldol coupling, amide alkynylation, and asymmetric ketone reduction. 相似文献
123.
Costa M Areias F Castro M Brea J Loza MI Proença F 《Organic & biomolecular chemistry》2011,9(11):4242-4249
A one-pot procedure was developed for the synthesis of novel 3-[amino(methoxy)methylene]-2-oxo-3,4-dihydro-2H-chromen-4-yl)-3-cyanoacetamides and chromeno[3,4-c]pyridine-1-carbonitriles from the reaction of 2-oxo-2H-chromene-3-carbonitriles and cyanoacetamides. These chromene derivatives were identified as new scaffolds for adenosine receptors and the hits 3a, 3c, 5a, and 5b were found. 相似文献
124.
We show that every nonempty compact and convex space M of probability Radon measures either contains a measure which has ‘small’ local character in M or else M contains a measure of ‘large’ Maharam type. Such a dichotomy is related to several results on Radon measures on compact spaces and to some properties of Banach spaces of continuous functions. 相似文献
125.
Quan Shi Narendiran Vitchuli Joshua Nowak Jane M. Caldwell Frederick Breidt Mohamed Bourham Xiangwu Zhang Marian McCord 《European Polymer Journal》2011,(7):1402-1409
Durable antibacterial Ag/polyacrylonitrile (Ag/PAN) hybrid nanofibers were prepared by atmospheric plasma treatment and electrospinning. Atmospheric helium plasma treatment was first used to reduce the AgNO3 precursor in pre-electrospinning solutions into metallic silver nanoparticles, followed by electrospinning into continuous and smooth nanofibers with Ag nanoparticles embedded in the matrix. SEM, TEM, and EDX spectra were used to study the structure and surface elemental composition of the nanofibers. Silver nanoparticles, with diameters ranging between 3 and 6 nm, were found to be uniformly dispersed in the nanofiber matrix. The Ag/PAN nanofibers exhibited slow and long-lasting silver ion release, which provided robust antibacterial activity against both Gram-positive Bacillus cereus and Gram-negative Escherichia coli microorganisms. 相似文献
126.
Quantum chemical methods have been employed to study the photophysics of thioxanthone in vacuum and various solvents. Structurally, the solvation leads to a lengthening of the carbonyl bond, whereas the benzene skeleton is mostly unaffected. This is mirrored by the larger blue shift of the (n(O)π*) states as compared to the red shift which the (ππ*) states undergo. For a proper understanding of the radiative and radiationless processes occurring, the excitation energy profile along a linearly interpolated path has been determined in various cases. The interesting interplay of excited states thus revealed, has been investigated to qualitatively suggest the relaxation pathways available (or dominant) in the cases under study. Rates for these processes have also been computed wherever possible. 相似文献
127.
Marian Genčev 《The Ramanujan Journal》2011,25(3):369-387
The aim of the paper is a new transformation of certain infinite series based on an identity from Sylvester also known as
the non-local derangement identity. Surprisingly, the result found can be applied to evaluate certain types of the generalized
hypergeometric function
p
F
q
(z) or infinite series involving the combination of hyperbolic functions, irrational functions and polynomials like
相似文献
128.
C.M. Marian F. Schneider M. Kleinschmidt J. Tatchen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(3):357-367
Electronic spectra of uracil in its diketo (lactam) form and five enol (lactim) tautomeric forms have been investigated by
means of combined density functional and configuration interaction methods. We have simulated the effects of hydrogen bonding
with a protic solvent by recomputing the spectrum of uracil in the presence of two, four, or six water molecules. Geometries
of the electronic ground state and several low-lying excited states have been optimized. Spin-orbit coupling has been determined
for correlated wavefunctions employing a non-empirical spin-orbit mean-field approach. In accord with experiment, we find
the diketo tautomer to be the most stable one. The calculations confirm that the first absorption band arises from the 1( π↦π*) S
0↦S
2 excitation. The experimentally observed vibrational structure in this band originates from a breathing mode of the six ring.
Complexation with water molecules is seen to cause a significant blue shift of n↦π* excitations while leaving π↦π* excitations nearly uninfluenced. Computed radiative lifetimes are presented for the experimentally known weak phosphorescence
from the π↦π* excited T1 state. Among the uracil lactim tautomers, one is particularly interesting from a spectroscopic point of view. In this tautomer,
the π↦π* excitation gives rise to the S1 state.
Received 18 February 2002 / Received in final form 5 June 2002 Published online 13 September 2002 相似文献
129.
Marian Bie 《Mathematical Methods in the Applied Sciences》2005,28(9):1007-1030
The existence of global‐in‐time weak solutions to the Joule problem modelling heating or cooling in a current and heat conductive medium is proved via the Faedo–Galerkin method. The existence proof entails some a priori estimates that together with the monotonicity and compactness methods make up a main tool to prove the desired result. Under appropriate hypotheses on the data, it will be shown the boundedness in L∞(QT) of the absolute temperature of the medium and of the t‐derivative of this temperature, which is achieved by means of the Gagliardo–Nirenberg theorem, the Sobolev embedding theorem and the method of Stampacchia. The paper is some extension of our investigation initiated in (Math. Meth. Appl. Sci. 1998; 23 :1275–1291). This extension includes relaxing some assumptions in (Math. Meth. Appl. Sci. 1998; 23 :1275–1291) and employing some new methods to establish the result. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
130.
Emre Alkan Andrew H. Ledoan Marian Vâjâitu Alexandru Zaharescu 《Monatshefte für Mathematik》2006,149(3):179-192
We provide bounds for the absolute discrepancy of sequences of fractions with denominators streaming in a given arithmetic
progression and satisfying divisibility constraints.
Supported by the CERES Program 4-147/2004 of the Romanian Ministry of Education and Research. 相似文献
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