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191.
Let A be a standard Koszul standardly stratified algebra and X an A-module. The paper investigates conditions which imply that the module Ext* A (X) over the Yoneda extension algebra A* is filtered by standard modules. In particular, we prove that the Yoneda extension algebra of A is also standardly stratified. This is a generalization of similar results on quasi-hereditary and on graded standardly stratified algebras. 相似文献
192.
Gréta Gergely Ferenc Wéber István Lukács Levente Illés Attila L. Tóth Zsolt E. Horváth Judit Mihály Csaba Balázsi 《Central European Journal of Chemistry》2010,8(2):375-381
Hydroxyapatite (HAp) was successfully produced from recycled eggshell, seashell and phosphoric acid. The phases obtained depended
on the ratio of calcined eggshell/ seashell to phosphoric acid, the calcination temperature and the mechanochemical activation
method (ball milling or attrition milling). The HAp structures were characterized by X-ray diffraction, scanning electron
microsopy and infrared spectroscopy. Attrition milling was more effective than ball milling, yielding nanosize, homogenous
and pure Hap.
相似文献
193.
194.
Lukáš Chytil Josef Cvačka Věra Marešová Branislav Štrauch Jiří Widimský Jr Martin Štícha Ondřej Slanař 《Journal of mass spectrometry : JMS》2010,45(10):1179-1185
Rilmenidine is an alpha 2 adrenoreceptor agonist used in the treatment of mild and moderate hypertension. In this study, a fast and accurate liquid chromatographic method with tandem mass spectrometric detection has been validated in order to assure quantification of rilmenidine in human serum. The fragmentation pathway of protonated rilmenidine was studied using high‐resolution mass spectrometry (HRMS). This study compared selectivity, linearity, accuracy, precision, extraction efficiency, matrix effect and sensitivity using common liquid–liquid extraction (LLE) and solid‐phase extraction (SPE) procedures. The limit of quantitation for both extraction techniques was 0.1 ng/ml. Several differences between the LLE and SPE have been observed in terms of linearity, accuracy, precision and matrix effect. Additionally, the advantages of SPE included less manual work load and increased recovery of rilmenidine in human serum to approximately 80% (LLE, 57%). The developed method involving SPE was found to be accurate (relative error (RE) < 5%), reproducible (relative standard deviation, RSD < 7%), robust and suitable for quantitative analysis of rilmenidine in serum samples obtained from patients under antihypertensive treatment. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
195.
Husár B Commereuc S Lukác I Chmela S Nedelec JM Baba M 《The journal of physical chemistry. B》2006,110(11):5315-5320
Mesh size distributions (MSDs) of swollen cross-linked styrene copolymer networks have been measured by thermoporometry using CCl(4) as a probe liquid. All numerical relationships required for the calculation of the MSD were established for both the liquid-to-solid and the solid-to-solid thermal transitions of CCl(4) and successfully validated on test samples. It was found that the polymer network, for both thermally and photo-cross-linked materials, was completely built in about 4 h of exposure. A clear correlation was established between the average mesh size of the swollen polymer network on one hand and the benzoyl peroxide groups content and swelling ratio on the other hand. 相似文献
196.
G. Subramania Y.J. Lee B.A. Hernandez-Sanchez A.J. Fischer T.S. Luk I. Brener P.G. Clem T.J. Boyle 《Photonics and Nanostructures》2008,6(1):12-VII
Control of light emission by engineering the electromagnetic vacuum is important in photonics for fundamental understanding as well as in applications. Omnidirectional photonic crystals such as logpile photonic crystals provide a very interesting system to study such phenomena. Here, we describe the first steps towards achieving systematic and reproducible control of light using titanium dioxide (TiO2) logpile photonic crystals (PC) with incorporated cadmium chalcogenide (CdSe) quantum dots (QDs) (λ 600 nm) to potentially modify QD photoluminescence (PL). We present a technique for coating a monolayer of the QDs on the PC rods based on 3-mercaptopropyltrimethoxysilanol linkage and measured the resulting PL response. Comparison of the PL spectra to a finite difference time domain model shows the need for further localization of QDs and fabrication of additional PC unit cells to observe PL modification. 相似文献
197.
R. Fardel M. Nagel T. Lippert F. Nüesch A. Wokaun B.S. Luk’yanchuk 《Applied Physics A: Materials Science & Processing》2008,90(4):661-667
The laser ablation of a photosensitive triazene polymer was investigated with a ns XeCl excimer laser over a broad range of
thicknesses (10–400 nm). We found that the ablation threshold fluence increased dramatically with decreasing film thickness
for films thinner than 50 nm. Ablation on substrates with different thermal properties (sapphire, fused silica, PMMA) was
investigated as well, and a clear influence of the substrate material was obtained. A mathematical model combining thermal
diffusion and absorption effects was used to explain the experimental data. The model is in good agreement with the experimental
data and shows that heat diffusion into the substrate plays a crucial role for the ablation process of very thin films.
PACS 52.38.Mf; 44.05.+e; 81.05.Lg 相似文献
198.
Induced Folding of Protein‐Sized Foldameric β‐Sandwich Models with Core β‐Amino Acid Residues 下载免费PDF全文
Gábor Olajos Dr. Anasztázia Hetényi Dr. Edit Wéber Lukács J. Németh Dr. Zsolt Szakonyi Prof. Dr. Ferenc Fülöp Prof. Dr. Tamás A. Martinek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(16):6173-6180
The mimicry of protein‐sized β‐sheet structures with unnatural peptidic sequences (foldamers) is a considerable challenge. In this work, the de novo designed betabellin‐14 β‐sheet has been used as a template, and α→β residue mutations were carried out in the hydrophobic core (positions 12 and 19). β‐Residues with diverse structural properties were utilized: Homologous β3‐amino acids, (1R,2S)‐2‐aminocyclopentanecarboxylic acid (ACPC), (1R,2S)‐2‐aminocyclohexanecarboxylic acid (ACHC), (1R,2S)‐2‐aminocyclohex‐3‐enecarboxylic acid (ACEC), and (1S,2S,3R,5S)‐2‐amino‐6,6‐dimethylbicyclo[3.1.1]heptane‐3‐carboxylic acid (ABHC). Six α/β‐peptidic chains were constructed in both monomeric and disulfide‐linked dimeric forms. Structural studies based on circular dichroism spectroscopy, the analysis of NMR chemical shifts, and molecular dynamics simulations revealed that dimerization induced β‐sheet formation in the 64‐residue foldameric systems. Core replacement with (1R,2S)‐ACHC was found to be unique among the β‐amino acid building blocks studied because it was simultaneously able to maintain the interstrand hydrogen‐bonding network and to fit sterically into the hydrophobic interior of the β‐sandwich. The novel β‐sandwich model containing 25 % unnatural building blocks afforded protein‐like thermal denaturation behavior. 相似文献
199.
Franz Lukács 《Mathematische Zeitschrift》1918,2(3-4):295-305
Ohne Zusammenfassung 相似文献
200.
FVEG methods have been developed over the last dozen years to approximate unsteady hyperbolic equations in several space dimensions.
In this survey the algorithmic origins of the methods are described. Then a detailed derivation of the methods is given, followed
by evidence of their stability and accuracy. Finally several examples of their application are given. 相似文献