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101.
Thermal properties of rapidly quenched alloys from the DyMn6?xGe6?xFexAlx (1 ? x ? 2.5) series produced by melt-spinning have been investigated by differential scanning calorimetry (DSC). The DSC curves show two exothermic effects connected with crystallization processes. Crystallization temperatures and enthalpies ΔH have been estimated. The systematic changes in these parameters allow concluding that the crystallization exothermic events are independent. Effective activation energies E have been determined using the Kissinger analysis and relatively high values up to 480 ± 20 kJ/mol for DyMn4Ge4Fe2Al2 have been found indicating high thermal stability of the amorphous state in this alloy series. 相似文献
102.
Świderski G. Świsłocka R. Łyszczek R. Wojtulewski S. Samsonowicz M. Lewandowski W. 《Journal of Thermal Analysis and Calorimetry》2019,138(4):2813-2837
Journal of Thermal Analysis and Calorimetry - The new 3d metal complexes of pyrimidine-2-carboxylic (2PCA) and pyrimidine-5-carboxylic (5PCA) acids were synthesized and characterized using thermal... 相似文献
103.
104.
N. Śkarica 《Mikrochimica acta》1952,39(4):336-338
Zusammenfassung Es wird ein einfaches Gerät beschrieben, das aus einer graduierten Kapillarpipette und einem Reservoir zur Aufnahme der Blutkörperchen besteht. Mit dessen Hilfe ist aus etwa 0,1 bis 0,2 ml Gesamtblut das Plasma in einer zur volumetrischen Abmessung geeigneten Form zu gewinnen. Die Möglichkeit der Verwendung des Gerätes für andere mikrochemische Zwecke wird erwähnt.
Mit 1 Abbildung. 相似文献
Summary A simple device has been described, consisting of a graduated capillary tube and a reservoir for the reception of blood corpuscles, by means of which the plasma can be obtained in a volumetrically measurable form from small volumes of blood (0.1 to 0.2 ml). The apparatus should be useful for other microchemical procedures.
Résumé On décrit un appareil simple constitué d'une pipette capillaire graduée et d'un réservoir pour prélever les globules du sang. A l'aide de cet appareil on peut obtenir, à partir de 0,1–0,2 ml de sang total, le plasma sous une forme appropriée à une mesure volumétrique. On mentionne la possibilité d'employer l'appareil pour d'autres buts microchimiques.
Mit 1 Abbildung. 相似文献
105.
Jędrzej Śniatycki 《Journal of Fixed Point Theory and Applications》2008,3(2):307-315
We consider a Hamiltonian action of a connected group G on a symplectic manifold (P, ω) with an equivariant momentum map and its quantization in terms of a K?hler polarization which gives rise to a unitary representation of G on a Hilbert space . If O is a co-adjoint orbit of G quantizable with respect to a K?hler polarization, we describe geometric quantization of algebraic reduction of J
−1(O). We show that the space of normalizable states of quantization of algebraic reduction of J
−1(O) gives rise to a projection operator onto a closed subspace of on which is unitarily equivalent to a multiple of the irreducible unitary representation of G corresponding to O. This is a generalization of the results of Guillemin and Sternberg obtained under the assumptions that G and P are compact and that the action of G on P is free. None of these assumptions are needed here.
Dedicated to Vladimir Igorevich Arnold 相似文献
106.
Dr. Susana Ibáñez Dr. Katarzyna Świderek Prof. Eduardo Peris 《Angewandte Chemie (International ed. in English)》2023,62(18):e202301914
Mechanically interlocked molecules (MIMs) have gained increasing interest during the last decades, not only because of their aesthetic appeal, but also because their unique properties have allowed them to find applications in nanotechnology, catalysis, chemosensing and biomedicine. Herein we describe how a pyrene molecule with four octynyl substituents can be easily encapsulated within the cavity of a tetragold(I) rectangle-like metallobox, by template formation of the metallo-assembly in the presence of the guest. The resulting assembly behaves as a mechanically interlocked molecule (MIM), in which the four long limbs of the guest protrude from the entrances of the metallobox, thus locking the guest inside the cavity of the metallobox. The new assembly resembles a metallo-suit[4]ane, given the number of protruding long limbs and the presence of the metal atoms in the host molecule. However, unlike normal MIMs, this molecule can release the tetra-substituted pyrene guest by the addition of coronene, which can smoothly replace the guest in the cavity of the metallobox. Combined experimental and computational studies allowed the role of the coronene molecule in facilitating the release of the tetrasubstituted pyrene guest to be explained, through a process that we named “shoehorning”, as the coronene compresses the flexible limbs of the guest so that it can reduce its size to slide in and out the metallobox. 相似文献
107.
In many practical situations the assumption of sound field dispersion needed for the application of the Sabine’s theory is not fulfilled. In general, sound field is sufficiently dispersed if there are no large differences in the dimensions of the room, limiting partitions are not parallel, or the sound absorbing material is uniformly distributed. In practice, very few of these requirements are satisfied. As a result, a number of other formulas describing reverberation time have been created, for example Fitzroy’s or Neubauer’s formulas. However, these methods in many cases differ significantly from the actual measurements. The paper presents a method used to estimate reverberation time as well as its applicability potential involving laboratory models and auditorium rooms. The proposed method can be classified into a group of learning methods and involves the use of statistical methods which allow for approximation with the use of the least squares method. 相似文献
108.
Accurate Kohn–Sham ionization potentials from scaled‐opposite‐spin second‐order optimized effective potential methods
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Szymon Śmiga Fabio Della Sala Adam Buksztel Ireneusz Grabowski Eduardo Fabiano 《Journal of computational chemistry》2016,37(22):2081-2090
One important property of Kohn–Sham (KS) density functional theory is the exact equality of the energy of the highest occupied KS orbital (HOMO) with the negative ionization potential of the system. This exact feature is out of reach for standard density‐dependent semilocal functionals. Conversely, accurate results can be obtained using orbital‐dependent functionals in the optimized effective potential (OEP) approach. In this article, we investigate the performance, in this context, of some advanced OEP methods, with special emphasis on the recently proposed scaled‐opposite‐spin OEP functional. Moreover, we analyze the impact of the so‐called HOMO condition on the final quality of the HOMO energy. Results are compared to reference data obtained at the CCSD(T) level of theory. © 2016 Wiley Periodicals, Inc. 相似文献
109.
We prove in an elementary way that for a Lipschitz domain \(D\subset \mathbb {C}^n\), all plurisubharmonic functions on D can be regularized near any boundary point. 相似文献
110.