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221.
Ferenc Krdi 《Journal of heterocyclic chemistry》1991,28(6):1549-1552
Methylquinolines 1–4 were chlorinated by heating with phosphorus pentachloride in chlorobenzenes to side-chain halogen derivatives 5–14 . Methyl groups of compounds 1–4 can be chlorinated to chloromethyl, dichloromethyl or trichloromethyl groups depending on their positions and the reaction conditions. 相似文献
222.
Consider the gradually more and more complexproblems of single row routing, channel routing and switchbox routing on the one hand, and the gradually less and less restrictivemodels (1-layer, Manhattan, unconstrained 2-layer, multilayer) on the other hand. The single row routing problems can always be solved in the Manhattan model, and the channel routing problem can always be solved in the unconstrained 2-layer model, in fact, both in linear time. In this paper, we show that the switchbox routing problem is solvable in the multilayer model, also in linear time.Supported in part by the Office of Naval Research (Grants N0001492J1375 and N0001492J4083) and by the Air Force Office of Scientific Research (Grants 89-0512B and F49620-93-1-0041).Research partially supported by the Hungarian National Foundation for Scientific Research (Grant No. OTKA 2118, 2505), and by the EC Cooperative Action IC 1000, Algorithms for Future Technologies (ALTEC). 相似文献
223.
Ferenc Weisz 《Journal of Fourier Analysis and Applications》2007,13(3):357-368
The inversion formula for the short-time Fourier transform is usually considered in the weak sense, or only for specific combinations
of window functions and function spaces such as L2 and modulation spaces. In the present note the Riemannian sums of the inverse short-time Fourier transform are investigated.
Under some conditions on the window functions we prove that the Riemannian sums converge to f in the modulation spaces and
inWiener amalgam norms, hence also in the Lp sense. 相似文献
224.
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226.
David P. Billington Dennis A. Nagy 《International Journal of Solids and Structures》1978,14(10):851-860
When the flexural acceleration of a plate is measured by an accelerometer, the mass of the accelerometer tends to reduce the magnitude of the acceleration.This study establishes a simple analytical relation between the accelerometer mass and the corresponding reduction of acceleration. This has been done by studying an idealized diffraction problem for the plate flexural waves.The complex frequency response depends upon the accelerometer mass, the frequency of the flexural wave, the plate thickness and the material parameters of the plate.A numerical filtering method is used to bring an experimental result and a corresponding numerical prediction closer together. 相似文献
227.
Direct analysis in real time mass spectrometry (DART‐MS) of highly non‐polar low molecular weight polyisobutylenes
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Lajos Nagy Tibor Nagy György Deák Ákos Kuki Borbála Antal Miklós Zsuga Sándor Kéki 《Journal of mass spectrometry : JMS》2015,50(9):1071-1078
Low molecular weight polyisobutylenes (PIB) with chlorine, olefin and succinic acid end‐groups were studied using direct analysis in real time mass spectrometry (DART‐MS). To facilitate the adduct ion formation under DART conditions, NH4Cl as an auxiliary reagent was deposited onto the PIB surface. It was found that chlorinated adduct ions of olefin and chlorine telechelic PIBs, i.e. [M + Cl]? up to m/z 1100, and the deprotonated polyisobutylene succinic acid [M? H]? were formed as observed in the negative ion mode. In the positive ion mode formation of [M + NH4]+, adduct ions were detected. In the tandem mass (MS/MS) spectra of [M + Cl]?, product ions were absent, suggesting a simple dissociation of the precursor [M + Cl]? into a Cl? ion and a neutral M without fragmentation of the PIB backbones. However, structurally important product ions were produced from the corresponding [M + NH4]+ ions, allowing us to obtain valuable information on the arm‐length distributions of the PIBs containing aromatic initiator moiety. In addition, a model was developed to interpret the oligomer distributions and the number average molecular weights observed in DART‐MS for PIBs and other polymers of low molecular weight. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
228.
Thermal Effects and Structural Changes of Photosynthetic Reaction Centers Characterized by Wide Frequency Band Hydrophone: Effects of Carotenoids and Terbutryn
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László Nagy Vladimir Kiss Vlad Brumfeld Károly Osvay Ádám Börzsönyi Melinda Magyar Tibor Szabó Márta Dorogi Shmuel Malkin 《Photochemistry and photobiology》2015,91(6):1368-1375
Photothermal characteristics and light‐induced structural (volume) changes of carotenoid‐containing and noncontaining photosynthetic reaction centers (RCs) were investigated by wide frequency band hydrophone. We found that the presence of carotenoid either does not play considerable role in the light‐induced conformational movements, or these rearrangements are too slow for inducing a photoacoustic (PA) signal. The kinetic component with a few tens of microseconds, exhibited by the carotenoid‐less RCs, appears to be similar to that of triplet state lifetimes, identified by other methods. The binding of terbutryn to the acceptor side is shown to affect the dynamics of the RC. Our results do not confirm large displacements or volume changes induced by the charge movements and by the charge relaxation processes in the RCs in few hundreds of microseconds time scale that accompanies the electron transfer between the primary and secondary electron acceptor quinones. 相似文献
229.
Krisztina Majer-Baranyi András Nagy Olga Bukovskaya István Szendrő András Székács 《International journal of environmental analytical chemistry》2015,95(6):481-493
A label-free, optical waveguide lightmode spectroscopy based immunosensor was developed for frog (Bombina orientalis) vitellogenin (Vtg) determination in biological samples as a biomarker for exogenous oestrogen compounds. Antibody against Vtg was produced in rabbits immunised with purified lipovitellin (Lpv), a precursor of Vtg, from the homogenised ovary of oriental fire-bellied toads (B. orientalis). The purified protein and Lpv/Vtg-specific serum were applied in both competitive and direct immunoassay formats using optical waveguide lightmode spectroscopy immunosensor. When measuring Vtg in direct manner, the Lpv antibody (1.76 µg mL?1) was immobilised on the sensor surface, and the linear measuring range for Vtg was 0.1–10 µg mL?1. During the competitive measurement, 100 ng mL?1 Lpv was applied for the immobilisation. The linear measuring range for Vtg was 0.5–50 ng mL?1. We studied the relative substrate specificity of the antibody, and it was concluded that the method is suitable for the sensitive and selective determination of Vtg levels in toads. Heart, liver and gonad samples from male animals were spiked with Vtg and were analysed using the newly developed method, and female toads and spawn samples were tested and compared to the calibration curve obtained by the spiked samples. 相似文献
230.
Zoltán Lóránt Nagy 《Journal of Graph Theory》2017,84(4):566-580
We study the existence and the number of k‐dominating independent sets in certain graph families. While the case namely the case of maximal independent sets—which is originated from Erd?s and Moser—is widely investigated, much less is known in general. In this paper we settle the question for trees and prove that the maximum number of k‐dominating independent sets in n‐vertex graphs is between and if , moreover the maximum number of 2‐dominating independent sets in n‐vertex graphs is between and . Graph constructions containing a large number of k‐dominating independent sets are coming from product graphs, complete bipartite graphs, and finite geometries. The product graph construction is associated with the number of certain Maximum Distance Separable (MDS) codes. 相似文献