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41.
B. Simons 《Crystal Research and Technology》2010,45(2):124-132
Thermodynamic parameters of melts (ΔHS, A0, A1) in the system Anorthite‐Diopside and Bi2O3‐Bi4B2O9 have been calculated by a rigorous application of solution thermodynamics. The data are internally consistent and yield values of ΔHS for Anorthite = 133 kJ/mole, Diopside = 81 kJ/mole, Bi2O3 = 19 kJ/mole and Bi4B2O9 = 39 kJ/mole. The activity of Anorthite and Diopside in an anorhtitic melt deviates negative from ideality, whereas a diopsidic melt behaves almost ideal. In a “Bi2O3” melt the activity of the Bi2O3 component is strongly positive, that of Bi4B2O9 is strongly negative. The opposite is observed for the “Bi4B2O9” melt. All calculated liquidi except the Bi4B2O9 liquidus closely match the experimental ones. In contrast to the experimental liquidus the calculated Bi4B2O9 liquidus has an inflection point. The crest of the metastable spinode (solvus) for a “Bi2O3” melt is close to the liquidus indicating melt separation at undercooling. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
42.
K. Bahedi M. AddouM. El Jouad Z. SofianiH. EL Oauzzani B. Sahraoui 《Applied Surface Science》2011,257(18):8003-8005
Nanocrystalline ZnO:Al thin films were deposited by reactive chemical pulverization spray pyrolysis technique on heated glass substrates at 450 °C to study their crystalline structure, composition, strain, stress, roughness characteristics and nonlinear optical susceptibility as a function of Al concentration (0, 2, 3, 5 at.%). The films were characterized by X-ray diffractometer (XRD), EDAX 9100 analyser, atomic force microscopy (AFM) and third harmonic generation (THG). The Al (3 at.%) doped ZnO thin films exhibited the lower strain/stress than undoped films. The nonlinear properties of the ZnO:Al thin films have been found to be influenced by the films strain/stress. 相似文献
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46.
D. Gotta M. Hennebach Y. -W. Liu V. Markushin L. M. Simons H. Fuhrmann A. Gruber J. Zmeskal P. Indelicato B. Manil D. Anagnostopoulos N. Nelms 《Czechoslovak Journal of Physics》2002,52(2):B169-B174
A new high-precision determination of the strong-interaction shift (∈1s) and broadening (Γ1s) of the ground state in pionic hydrogen (πH) has been started at PSI. This constitutes a direct measurement of the πN scattering lengths and is an important test of the methods of chiral perturbation theory.The experiment will be conducted in two steps. In the first step we aim for a precision of 0.2% for ∈1s and 3% for Γ1s. A new method of energy calibration is used: by measuring πH simultaneously with pionic oxygen (πO), systematic errors are suppressed. The goal for the second step is an accuracy of 1% for Γ1s. 相似文献
47.
StefaanJ.R. Simons Federica Pratola AlanG. Jones Michael Brunsteiner SallyL. Price 《Particle & Particle Systems Characterization》2004,21(4):276-283
A novel experimental apparatus has been developed which enables the measurement of adhesion forces between two crystals suspended in a supersaturated solution and allowed to agglomerate over a fixed time period. The geometry of the crystal surfaces at the contact points and the dynamic development of the bond are captured on video and characterised using an image analysis technique. The experimental apparatus has been designed to allow control of supersaturation, orientation of crystal faces, distance between crystals, relative movement of crystals and contact time. The experimental results show that the agglomerate bond strength, expressed as the agglomerate adhesion force per unit contact area, increases with increasing supersaturation and is higher for faster growing faces than for slower growing faces. In addition, a qualitative comparison has been made between the measured force and a theoretical estimation of the interaction force between crystal faces, determined through molecular modelling. It is shown that the speed of approach of two opposing crystal faces is a key parameter in the nature of the subsequent bond, as is their atomic structure. 相似文献
48.
Styrene butadiene (SBR) and natural rubber (NR) can be used as binding matrices to control the release of zinc (Zn) which is a micro-nutrient for plants. The leaching rate of zinc in an aqueous medium depends on the concentration of zinc sulphate loaded in the two types of rubber used, the temperature of the surrounding environment and the pH of the aqueous medium. Water uptake was increased with increasing concentration of ZnSO4. The sustained release of zinc ions from the investigated formulations was prolonged for over five months. The mechanical properties of the vulcanizates were affected as the concentration of zinc sulphate changed. 相似文献
49.
Kinetics of deformation and fracture of nickel–iron alloy Inconel 718 under dynamic shear loading was measured using a split
torsional Hopkinson bar facility and high-speed photography. Tubular specimens with a reduced gage length and a starter notch
were sheared at strain rates up to 6 × 103 s−1. High-speed photographs of fiducial lines scribed on the specimen surface showed the development of local strains and cracking.
This paper describes the experimental and analytical procedures, illustrates average and local plastic strain evolution, and
presents shear crack initiation times and propagation speeds. 相似文献
50.
D. Gotta F. D. Amaro D. F. Anagnostopoulos P. Bühler H. Gorke D. S. Covita H. Fuhrmann A. Gruber M. Hennebach A. Hirtl T. Ishiwatari P. Indelicato T. S. Jensen E.-O. Le Bigot V. E. Markushin J. Marton M. Nekipelov V. N. Pomerantsev V. P. Popov J. M. F. dos Santos S. Schlesser Ph. Schmid L. M. Simons Th. Strauch M. Theisen M. Trassinelli J. F. C. A. Veloso J. Zmeskal 《Hyperfine Interactions》2015,234(1-3):105-111