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101.
Bruce E. Sagan Jaejin Lee 《Journal of Algorithms in Cognition, Informatics and Logic》2006,59(2):149-161
Eğecioğlu and Remmel [Linear Multilinear Algebra 26 (1990) 59–84] gave an interpretation for the entries of the inverse Kostka matrix K−1 in terms of special rim-hook tableaux. They were able to use this interpretation to give a combinatorial proof that KK−1=I but were unable to do the same for the equation K−1K=I. We define an algorithmic sign-reversing involution on rooted special rim-hook tableaux which can be used to prove that the last column of this second product is correct. In addition, following a suggestion of Chow [preprint, math.CO/9712230, 1997] we combine our involution with a result of Gasharov [Discrete Math. 157 (1996) 193–197] to give a combinatorial proof of a special case of the (3+1)-free Conjecture of Stanley and Stembridge [J. Combin. Theory Ser. A 62 (1993) 261–279]. 相似文献
102.
John J. Quinn Arkadiusz Wjs Anna Gadysiewicz 《Physica E: Low-dimensional Systems and Nanostructures》2006,34(1-2):280
A new kind of many-body excitonic state composed of fractionally charged constituents is introduced. The constituents are a trion (X-) embedded in an incompressible electron liquid and Laughlin quasiholes (QH's). Laughlin electron–trion correlations lead to an effective trion charge of -e/3. This many-body excitation is called “quasiexciton” and denoted by to distinguish it from a normal trion. The can bind one or two (e/3)-charged QH's, giving a neutral or a positive . The energy spectra and photoluminescence from radiative quasiexciton decay are studied numerically and interpreted using a generalized composite Fermion model of the e–X- fluid. 相似文献
103.
Tomasz ?ojewski Katarzyna Zi?ba Arkadiusz Knapik Jacek Bagniuk Anna Lubańska Joanna ?ojewska 《Applied Physics A: Materials Science & Processing》2010,100(3):809-821
The study presents an overview of the chromatographic (SEC), spectroscopic (FTIR, UV/VIS), viscometric (DP) and chemical methods
(titration, pH) used for the evaluation of the degradation progress of various kinds of paper under various conditions. The
methods were chosen to follow different routes of paper degradation. Model paper samples represented boundary paper types
from pure cellulose cotton paper, through softwood to low quality acidic, sized groundwood paper The accelerated ageing conditions
were adjusted to achieve maximum effect (climatic chamber RH 59%, 90oC) and also to mimic the environment inside books (closed vials). The results were settled on the literature data on the degradation
mechanisms and compared in terms of the paper types and ageing conditions. The estimators of coupled de-polymerisation and
oxidation have been proposed based on the correlation between SEC, UV/VIS and titrative coppper number determination. The
overall oxidation index derived from FTIR results was shown to correlate with the summary –CHO and –COOH concentration determined
by titrative methods. 相似文献
104.
Mariusz Mital Nina E. Wezynfeld Tomasz Frczyk Magdalena Z. Wiloch Urszula E. Wawrzyniak Arkadiusz Bonna Carolin Tumpach Kevin J. Barnham Cathryn L. Haigh Wojciech Bal Simon C. Drew 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(36):10606-10610
Accumulation of the β‐amyloid (Aβ) peptide in extracellular senile plaques rich in copper and zinc is a defining pathological feature of Alzheimer′s disease (AD). The Aβ1–x (x=16/28/40/42) peptides have been the primary focus of CuII binding studies for more than 15 years; however, the N‐truncated Aβ4–42 peptide is a major Aβ isoform detected in both healthy and diseased brains, and it contains a novel N‐terminal FRH sequence. Proteins with His at the third position are known to bind CuII avidly, with conditional log K values at pH 7.4 in the range of 11.0–14.6, which is much higher than that determined for Aβ1–x peptides. By using Aβ4–16 as a model, it was demonstrated that its FRH sequence stoichiometrically binds CuII with a conditional Kd value of 3×10−14 M at pH 7.4, and that both Aβ4–16 and Aβ4–42 possess negligible redox activity. Combined with the predominance of Aβ4–42 in the brain, our results suggest a physiological role for this isoform in metal homeostasis within the central nervous system. 相似文献
105.
Arkadiusz Rudzki 《Phase Transitions》2015,88(5):513-520
The influence of differential nanoparticles on the properties of ferroelectric liquid crystal based on chiral thiobenzoates series was investigated by optical and electro-optical methods. MHOBS4/ZnO, MHOBS4/Ag and MHOBS10/SWCN nanocomponents were prepared. A small addition of nanoparticles leads to changes in electro-optical properties. This is due probably to the various mutual arrangements of nanoparticles and liquid crystal molecules. 相似文献
106.
Lucyna A. Woźniak Arkadiusz Chworoś Wojciech J. Stec 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Miwed phosphorus-carboxylic anhydrides have demonstrated both acylating and phosphorylating properties.[1] Here we report the reactivity of O,O-diethyl(O-2,4,6-trimethylbenzoyl) phosphates (1), and O-methyl (O-2,4,6-trimetyIbenzoyl) dimethylphosphonates (2)with nucleophiles in the presence of different strong organic bases (DBU, DMAP). 相似文献
107.
Dr. Iwona Olejniczak Arkadiusz Frąckowiak Prof. Roman Świetlik Dr. Tatiana G. Prokhorova Prof. Eduard B. Yagubskii 《Chemphyschem》2013,14(17):3925-3935
The polarized infrared reflectance and Raman spectra of the three quasi‐two‐dimensional β′′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]?Y bifunctional charge‐transfer salts, where BEDT‐TTF=bis(ethylenedithio)tetrathiafulvalene and Y=C6H5Br, (C6H5CN)0.17(C6H5Br)0.83, (C6H5CN)0.4(C6H5F)0.6, have been measured as a function of the temperature. Signatures of charge inhomogenity have been found in both Raman and infrared spectra of the β′′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]?Y superconductors. A 100 K transition to a mixed insulating/metallic state is clearly seen for the first time in the temperature dependence of the electronic spectra of superconducting β′′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]?C6H5Br. We suggest that this phase transition is due to subtle changes in the ethylene groups ordering, which are related to a structural phase transition in the anionic layer. The infrared and Raman spectra of quasi‐two‐dimensional metal α‐′pseudo‐κ′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]C6H4Br2 are also investigated. 相似文献
108.
A GC–MS/MS method with EI ionization was developed and validated to detect and quantify N-nitrosodimethylamine (NDMA) and seven other nitrosamines in 105 samples of metformin tablets from 13 different manufactures. Good linearity for each compound was demonstrated over the calibration range of 0.5–9.5 ng/mL. The assay for all substances was accurate and precise. NDMA was not detected in the acquired active pharmaceutical ingredient (API); however, NDMA was detected in 64 (85.3%) and 22 (91.7%) of the finished product and prolonged finished product samples, respectively. European Medicines Agency recommends the maximum allowed limit of 0.032 ppm in the metformin products. Hence, 28 finished products and 7 pronged dosage products were found to exceed the acceptable limit of daily intake of NDMA contamination. The implications of our findings for the testing of pharmaceutical products are discussed. 相似文献
109.
We determine the Möbius function of a poset of compositions of an integer. In fact, we give two proofs of this formula, one using an involution and one involving discrete Morse theory. This composition poset turns out to be intimately connected with subword order, whose Möbius function was determined by Björner. We show that, using a generalization of subword order, we can obtain both Björner’s results and our own as special cases. 相似文献
110.
JPC – Journal of Planar Chromatography – Modern TLC - The cyclooxygenase inhibitors lornoxicam, meloxicam, piroxicam, and tiaprofenic acid have been separated by normal- and... 相似文献