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961.
A. Di Maio A. Rocco P. Ferraro M. De Rosa P. De Natale S. De Nicola A. Finizio G. Pierattini G. Coppola M. Iodice V. Striano 《Optics and Lasers in Engineering》2007,45(3):385
In view of the growing interest for non-destructive tests of materials, geodynamical monitoring and in general remote sensing, there is a great effort to bring practical optical sensors from research labs to industrial and environmental applications. In this paper, we employ digital holographic technique as an efficient tool for evaluating the strain measurement capability of fiber Bragg gratings (FBG). A cantilever beam has been employed as a test structure under loading test. The strain measurements results obtained by fiber-based sensors have been compared to those obtained by using full-field digital holographic technique and point-wise strain gauge sensors glued on the same cantilever beam. A simple theoretical model is also presented to interpret and compare the experimental results coming from different techniques. 相似文献
962.
A new approach to identify the independent amplitudes along with their partial wave multipole expansions, for photo-and electro-production
is suggested, which is generally applicable to mesons with arbitrary spin-parity. These amplitudes facilitate direct identification
of different resonance contributions.
相似文献
963.
Humberto Bustos Rodriguez Dagoberto Oyola Lozano Yebrayl A. Rojas Martínez Germán A. Pérez Alcázar Stefan Flege Adam G. Balogh Louis J. Cabri Michael Tubrett 《Hyperfine Interactions》2007,175(1-3):195-206
X-ray diffraction (XRD), Mössbauer spectrometry (MS), secondary ions mass spectroscopy (SIMS) and laser-ablation microprobe–inductively coupled plasma–mass spectrometry (LAM–ICP–MS) were used to study mineral samples of Colombian auriferous ores collected from the “El Diamante” mine, located in the municipality of Guachavez-Nariño, in Colombia. The samples were prepared as polished thin sections and polished sections. From XRD data, quartz, sphalerite and pyrite were detected and their respective cell parameters were estimated. From MS analyses, pyrite, arsenopyrite and chalcopyrite were identified; their respective hyperfine parameters and respective texture were deduced. Multiple regions of approximately 200 × 200 μm in each sample were analyzed with SIMS; the occurrence of “invisible gold” associated mainly with pyrite and secondarily with arsenopyrite could thus be assigned. It was also found that pyrite is of the arsenious type. Spots from 30 to 40 μm in diameter were analyzed with LAM–ICP–MS for pyrite, arsenopyrite and sphalerite; Au is “homogeneously” distributed inside the structure of the arsenious pyrite and the arsenopyrite (not as inclusions); the chemical composition indicates similarities of this “invisible gold”, forming a solid solution with arsenious pyrite and arsenopyrite. One hundred nineteen and 62 ppm of ‘invisible gold’ was quantified in 21 spots analyzed on pyrite and in 14 spots on arsenopyrite, respectively. 相似文献
964.
965.
Jalal M. Nawash Brendan Twamley Kelvin G. Lynn 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(8):i66-i68
Our investigations into the ZnO–TeO2 system have produced a new phase, zinc(II) hexatellurium(IV) tridecaoxide, ZnTe6O13, with trigonal (R) symmetry, synthesized by repeated heating and cooling to a maximum temperature of 1053 K. The asymmetric unit consists of a Zn atom coordinated in a distorted octahedral fashion by two unique tellurium(IV) oxide units that form trigonal–bipyramidal TeO4 and TeO3+1 corner‐ and edge‐shared polyhedra. Except for the Zn and an O atom, which occupy 6c positions, all atoms occupy 18f general positions. 相似文献
966.
Bahattin Gümgüm Nermin Biricik Feyyaz Durap Ismail Özdemir Nevin Gürbüz Wee Han Ang Paul J. Dyson 《应用有机金属化学》2007,21(8):711-715
Palladium(II) complexes with N,N‐bis(diphenylphosphino)aniline ligands catalyse the Heck reaction between styrene and aryl bromides, affording stilbenes in good yield. The structures of two of the complexes used as pre‐catalysts have been determined by single‐crystal X‐ray diffraction. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
967.
Vlasov Yu. G. Murzina Yu. G. Legin A. V. Ermolenko Yu. E. Schubert J. Schüoning M. J. Lut H. 《Russian Journal of Applied Chemistry》2002,75(3):351-356
Methods of silicon planar technology and pulsed laser deposition were applied to fabricate fully solid-state chemical sensors for determining ions of copper, lead, cadmium, thallium, and also sulfide and chloride ions on the basis of thin chalcogenide films as ion-sensitive membranes. 相似文献
968.
N. H. Abu-Hamdeh 《Heat and Mass Transfer》2002,38(7-8):687-693
The analytical solutions of equations describing the dynamics of distributed parameter systems are usually complicated in
form and derivations and inconvenient to use for simulation and control system design. The liquid–liquid counter flow heat
exchanger is an example of these disturbed parameter systems. An analytical solution of the dynamics of a symmetrically operated
counter flow heat exchanger in the form of transfer function matrix is investigated in open-loop and close-loop conditions.
The resulting non-linear model was linearized using perturbation approach. A feed-forward path controller to counteract at
any disturbances in the boundary temperature and a non-interactive controller to decouple the outputs were implemented.
Received on 22 February 2001 / Published online: 29 November 2001 相似文献
969.
A modernized conception of hierarchical structure of reality is proposed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 3–6, December, 1980. 相似文献
970.
After a discussion of a space of test functions and the corresponding space of distributions, a family of Banach spaces (B, ∥ ∥B) in standard situation is described. These are spaces of distributions having a pointwise module structure and also a module structure with respect to convolution. The main results concern relations between the different spaces associated to B established by means of well-known methods from the theory of Banach modules, among them B0 and , the closure of the test functions in B and the weak relative completion of B, respectively. The latter is shown to be always a dual Banach space. The main diagram, given in Theorem 4.7, gives full information concerning inclusions between these spaces, showing also a complete symmetry. A great number of corresponding formulas is established. How they can be applied is indicated by selected examples, in particular by certain Segal algebras and the Ap-algebras of Herz. Various further applications are to be given elsewhere. 相似文献