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141.
Alvarez Ruiz J Kivimäki A Stankiewicz M Melero García E Coreno M Ali S Koperski J Rachlew E Vall-Llosera I Serrano G Feyer V Tuckett R 《Physical chemistry chemical physics : PCCP》2006,8(44):5199-5206
The interaction of SF(5)CF(3) with vacuum-UV radiation has been investigated by photon induced fluorescence spectroscopy. Total fluorescence yield and dispersed fluorescence spectra of SF(5)CF(3) were recorded in the 200-1000 nm fluorescence window. In all cases, the fluorescence spectra resemble those of CF(3)X (X = H, F, Cl, and Br) molecules. At photon energies below 20 eV, the emission is attributed to the excited CF(3) and CF(2) fragments. The threshold for the CF(3) emission is 10.2 +/- 0.2 eV, giving an upper limit estimate for the SF(5)-CF(3) bond dissociation energy of 3.9 +/- 0.3 eV. The excitation functions of the CF(3) and CF(2) emissions were measured in the photon energy range 13.6-27.0 eV. The resonant structures observed in SF(5)CF(3) are attributed to electronic transitions from valence to Rydberg orbitals, following similar assignments in CF(3)X molecules. The photoabsorption spectrum of SF(5)CF(3) shows features at the same energies, indicating a strong contribution from Rydberg excitations. 相似文献
142.
Oberacher H Pitterl F Niederstätter H Weiss EM Stadelmann E Marksteiner J Parson W 《Analytical and bioanalytical chemistry》2006,386(1):83-91
The applicability of ion-pair reversed-phase high-performance liquid chromatography hyphenated to electrospray ionization
time-of-flight mass spectrometry (ICEMS) for the haplotyping of five SNPs (rs769223, rs4818, rs4986871, rs8192488, rs4680)
located within exon 4 of the human catechol-O-methyltransferase (COMT, EC 2.1.1.6) gene is demonstrated. Two differently sized
products of polymerase chain reaction—a 71-bp amplicon partially covering the sequence of a 124-bp amplicon—were used to determine
unequivocally the allelic states of the single nucleotide polymorphisms linked on both chromosomes. The two amplicons were
co-loaded onto the chromatographic column and simultaneously analyzed within a single gradient run. Using the described strategy,
101 individuals representing an Austrian population sample were typed. The obtained haplotype frequencies will serve as reference
values in future association studies to examine the impact of the COMT gene on neuropsychiatric disorders. Additionally, two
newly discovered polymorphic sites within the sequence of the COMT gene are described (a synonymous C>T mutation at the third
position of the amino acid codon 99 in the soluble COMT protein or 149 in the membrane-bound COMT protein; a non-synonymous
G>A substitution at the second position of the amino acid codon 95 in the soluble COMT protein or 145 in the membrane-bound-COMT
protein). 相似文献
143.
William Devenport Elisabeth A. Wahl W. Nathan Alexander 《Journal of sound and vibration》2010,329(19):3958-3971
This paper presents measurements of the wavenumber frequency spectrum of wall pressure fluctuations under a turbulent boundary layer made using sound radiated from hydrodynamically smooth ridges in the surface. The measurements also serve as a test of the scattering theory of roughness noise. The radiated sound reveals a cut through the full three-dimensional wavenumber frequency spectrum of the wall pressure at the wavenumber of the surface. Since ridges can be made with very small wavelengths, this technique can be used to probe the structure of the wall pressure spectrum on scales far smaller than those that can be reached using conventional wall-mounted transducers. Furthermore, the method reveals the wavenumber frequency spectrum directly, without the need for multi-point measurements or the spatial Fourier transforming of data. Measured spectra bear a close similarity to Corcos’ and Chase's model forms, and confirm the applicability of the theory of roughness noise and its prediction of roughness noise directivity. 相似文献
144.
Jiawei Chen Elisabeth Köbis Markus Köbis Jen-Chih Yao 《Journal of Optimization Theory and Applications》2018,177(3):816-834
In this paper, we employ the image space analysis to study constrained inverse vector variational inequalities. First, sufficient and necessary optimality conditions for constrained inverse vector variational inequalities are established by using multiobjective optimization. A continuous nonlinear function is also introduced based on the oriented distance function and projection operator. This function is proven to be a weak separation function and a regular weak separation function under different parameter sets. Then, two alternative theorems are established, which lead directly to sufficient and necessary optimality conditions of the inverse vector variational inequalities. This provides a partial answer to an open question posed in Chen et al. (J Optim Theory Appl 166:460–479, 2015). 相似文献
145.
We prove new Alexandrov-Fenchel type inequalities and new affine isoperimetric inequalities for mixed p-affine surface areas. We introduce a new class of bodies, the illumination surface bodies, and establish some of their properties.
We show, for instance, that they are not necessarily convex. We give geometric interpretations of L
p
affine surface areas, mixed p-affine surface areas and other functionals via these bodies. The surprising new element is that not necessarily convex bodies
provide the tool for these interpretations. 相似文献
146.
Stefan Markus Giebel Daniela Hosser 《Central European Journal of Operations Research》2013,21(2):411-413
This longitudinal study examined stability and change of delinquency among young offenders after their release. The sample consists of male Germans (N = 2405) who were incarcerated in five juvenile prisons in different federal states. Standardized interviews were repeatedly conducted with the prisoners during imprisonment and after release to gather information about personal and social risk as well as protective factors. Based on official criminal records, delinquency was registered up to eight years after the first incarceration. The time interval between release and recidivism, severity of offending and the kind of punishment was observed. Applying of Trajectory Analysis according to Nagin (2005) three distinct developmental trajectories can be identified differing in both level of and change in offending over time: Occasional offenders, high level offenders and age-limited offenders. The groups differ in personal and social factors. Results are discussed with regard to offender treatment and prison aftercare. 相似文献
147.
If a given dynamical process contains an inherently unpredictable component, it may be modeled as a stochastic process. Typical examples from financial markets are the dynamics of prices (e.g. prices of stocks or commodities) or fundamental rates (exchange rates etc.). The unknown future value of the corresponding stochastic process is usually estimated as the expected value under a suitable measure, which may be determined from distribution of past (historical) values. The predictive power of this estimation is limited by the simplifying assumptions of common calibration methods. Here we propose a novel method of “intelligent” calibration, using learning (2-layer) neural networks in order to dynamically adapt the parameters of a stochastic model to the most recent time series of fixed length (memory depth) to the past. The process parameters are determined by the weights of the intermediate layer of the neural network. The final layer combines these parameters in a meaningful manner yielding the forecasting value for the stochastic process. On each actual finite memory, the neural network is trained by back-propagation, obtaining a much more flexible and realistic parameter calibration than an analogous fit to an autoregressive models could do. In the context of processes related to financial assets, the final combination of the output layer relates to their market-price-of-risk. The back propagation is limited to the typical memory length of the financial market (for example 10 previous business days). We demonstrate the learning efficiency of the new algorithm by tracking the next-day forecasts with one typical examples each, for the asset classes of currencies and stocks. 相似文献
148.
This paper is concerned with a result of homogenization of a non-local first order Hamilton–Jacobi equation describing the dislocations dynamics. Our model for the interaction between dislocations involves both an integro-differential operator and a (local) Hamiltonian depending periodicly on u/ε. The first two authors studied in a previous work homogenization problems involving such local Hamiltonians. Two main ideas of this previous work are used: on the one hand, we prove an ergodicity property of this equation by constructing approximate correctors which are necessarily non periodic in space in general; on the other hand, the proof of the convergence of the solution uses here a twisted perturbed test function for a higher dimensional problem. The limit equation is a nonlinear diffusion equation involving a first order Lévy operator; the nonlinearity keeps memory of the short range interaction, while the Lévy operator keeps memory of long ones. The homogenized equation is a kind of effective plastic law for densities of dislocations moving in a single slip plane. 相似文献
149.
150.
Georgios Mourgas Elisabeth Giebel Volker Bauch Tanja Schneck Joerg Unold Michael R. Buchmeiser 《先进技术聚合物》2019,30(11):2872-2882
Flame‐retarded polyamide 6.6 (FR‐PA6.6) was prepared by the cocondensation of hexamethylene diammonium adipate (AH‐salt) with the corresponding salts of hexamethylene diamine and two different organophosphorus compounds, namely, 3‐hydroxyphenylphosphinylpropanoic acid (3‐HPP, 1) and 9,10‐dihydro‐10‐[2,3‐di (hydroxycarbonylpropyl]‐10‐phosphaphenanthrene‐10‐oxide (DDP, 2). The incorporation of the phosphorus comonomers and the thermal and physical properties of the resulting copolyamides have been studied. The phosphorus‐modified FR‐PA6.6 possesses high relative viscosities of 2.0 to 2.4, good thermal stability, and was used for the production of polyamide blends by merging FR‐PA6.6 with commercial PA6. This offered access to flame‐retarded PA6 multifilaments, which possess tensile strengths up to 0.7 GPa and elastic moduli up to 6.2 GPa. Knitted fabrics of FR‐PA6 exhibit high limiting oxygen index (LOI) values between 36 and 38 and executed burning tests demonstrate that the incorporation of phosphorus‐based comonomers improve flame retardancy significantly. The approach presented here offers a straightforward access to effective flame retardancy in nylon 6. 相似文献