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Residual stresses are important by the manufacturing of the most components. The analysis of residual stresses using the hole-drilling method is complicated and is based at the moment solely on strain measurement on the surface. Now, an approach is described where the residual stresses can be calculated on the basis of strain measured in several plains. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Vegar Stockmann 《Tetrahedron》2008,64(32):7626-7632
Two new types of pyrido-fused tris-heterocycles (1a,b and 2a,b) have been prepared from 3-aminopyridine in five/six steps. A synthetic strategy for the preparation of the novel pyrido[3,4-b]thieno[2,3- and 3,2-d]pyrroles (1a,b) and pyrido[4,3-e]thieno[2,3- and 3,2-c]pyridazines (2a,b) has been studied. The Suzuki cross coupling of the appropriate 2- and 3-thienoboronic acids (3,4) and 4-bromo-3-pyridylpivaloylamide (9) afforded the biaryl coupling products (10,11) in high yields (85%). Diazotization of the hydrolysed (2-thienyl)-coupling product (12) and azide substitution gave the 3-azido-4-(2-thienyl)pyridine intermediate (72%, 14). 3-Azido-4-(3-thienyl)pyridine (15) was prepared by exchanging the previous order of reactions. The desired β-carboline thiophene analogues (1a,b) were obtained via the nitrene by thermal decomposition of the azido precursors (14,15). By optimising conditions for intramolecular diazocoupling, the corresponding pyridazine products (72-83%, 2a,b) were afforded. 相似文献
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A room temperature ionic liquid (IL) composed of a quaternary alkylphosphonium (trihexyltetradecylphosphonium, P66614+) and tetrakis(pentafluorophenyl)borate anion (TB−) was employed within a water|P66614TB (w|P66614TB or w|IL) biphasic system to evaluate cesium ion extraction in comparison to that with a traditional water|organic solvent (w|o) combination. 137Cs is a major contributor to the radioactivity of spent nuclear fuel as it leaves the reactor, and its extraction efficiency is therefore of considerable importance. The extraction was facilitated by the ligand octyl(phenyl)-N,N′-diisobutylcarbamoylphosphine oxide (CMPO) used in TRans-Uranium EXtraction processes and investigated through well established liquid|liquid electrochemistry. This study gave access to the metal ion to ligand (1:n) stoichiometry and overall complexation constant, β, of the interfacial complexation reaction which were determined to be 1:3 and 1.6 × 1011 at the w|P66614TB interface while the study at w|o elicited an n equal to 1 with β equal to 86.5. Through a straightforward relationship, these complexation constant values were converted to distribution coefficients, δα, with the ligand concentrations studied for comparison to other studies present in the literature; the w|o and w|IL systems gave δα of 2 and 8.2 × 107, respectively, indicating a higher overall extraction efficiency for the latter. For the w|o system, the metal ion-ligand stoichiometries were confirmed through isotopic distribution analysis of mass spectra obtained by the direct injection of an emulsified water–organic solvent mixture into an electron spray ionization mass spectrometer. 相似文献
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The recognition of very stiff axial elastic motion compared to the motion in the transverse direction for cable dynamics motivates separation of the axial and transversal dynamics. For certain applications, e.g. real-time model-based control, fast calculation of the transverse motion may be of high importance, motivating the development of numerically efficient software code. Separation of axial dynamics renders possible neglection or simplification of the axial dynamics if appropriate for the system studied. A model is proposed with the assumption of axial inextensible material and negligible bending, torsion and shear stiffness in the cable. Experiments are carried out to verify the model, and the results are compared with simulations. The comparison between the experiments and numerical simulations showed good agreement up to the second frequency range with resonant behavior and the corresponding motion amplitudes. 相似文献
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A mechanical switch developed earlier for routing light in multimode optical fibers has been improved by reducing its cubic volume, insertion loss, switching time, and required switching power. Using an immersion fluid, an insertion loss below 0.5 dB was realized. The switching time is shorter than 13 msec, and the required switching power less than 16 mW. 相似文献
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Wolfgang E. S. Unger Mathias Senoner Jörg M. Stockmann Vincent Fernandez Neal Fairley Cristiana Passiu Nicholas D. Spencer Antonella Rossi 《Surface and interface analysis : SIA》2022,54(4):320-327
ISO 18516:2019 Surface chemical analysis—Determination of lateral resolution and sharpness in beam-based methods with a range from nanometres to micrometres revises ISO 18516:2006 Surface chemical analysis—Auger electron spectroscopy and X-ray photoelectron spectroscopy—Determination of lateral resolution. It implements three different methods delivering parameters useful to express the lateral resolution: (1) the straight edge method, (2) the narrow line method and (3) the grating method. The theoretical background of these methods is introduced in ISO/TR 19319:2013 Surface chemical analysis—Fundamental approaches to determination of lateral resolution and sharpness in beam-based methods. The revised International Standard ISO 18516 delivers standardized procedures for the determination of the (1) effective lateral resolution by imaging of square-wave gratings, the (2) lateral resolution expressed as the parameter D12–88 characterizing the steepness of the sigmoidal edge spread function (ESF) determined by imaging a straight edge and (3) the lateral resolution expressed as the full width of half maximum of the line spread function (LSF), wLSF, determined by imaging a narrow line. The last method also delivers information on the shape of the LSF, which characterizes an individual imaging instrument. Finally, the implementation of all three standardized methods in the field of imaging laboratory X-ray photoelectron spectroscopy (XPS) is shortly presented. This part of the letter is based on the use of a new test sample developed at ETH Zurich, Switzerland. This test sample displays a micrometre scaled pattern motivated by the resolving power of recent imaging XPS instruments. 相似文献
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The coupling of a quantum mechanical system to open decay channels has been theoretically studied in numerous works, mainly in the context of nuclear physics but also in atomic, molecular, and mesoscopic physics. Theory predicts that with increasing coupling strength to the channels the resonance widths of all states should first increase but finally decrease again for most of the states. In this Letter, the first direct experimental verification of this effect, known as resonance trapping, is presented. In the experiment a microwave Sinai cavity with an attached waveguide with variable slit width was used. 相似文献
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Mark I. Stockmann 《Physics letters. A》1980,76(2):191-193
A method of two-photon affinity modification of macromolecules (TAM) is proposed and founded theoretically. The method allows one to introduce with high efficiency radiation damages, especially breakages, into given parts of macromolecules. The method can be used in biology and biophysics. 相似文献
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