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21.
Doan Nguyen 《Ukrainian Mathematical Journal》2004,56(10):1633-1645
We prove a generalization of the Brody reparametrization lemma.__________Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 56, No. 10, pp. 1369 – 1377, October, 2004. 相似文献
22.
Nguyen Minh Chuong Bui Kien Cuong 《Proceedings of the American Mathematical Society》2004,132(12):3589-3597
A class of Cauchy problems for interesting complicated periodic pseudodifferential equations is considered. By the Galerkin-wavelet method and with weak solutions one can find sufficient conditions to establish convergence estimates of weak Galerkin-wavelet solutions to a Cauchy problem for this class of equations.
23.
A systematic study of the upper semicontinuity and the lower semicontinuity of the solution map in parametric affine variational
inequalities is given in this paper. Several examples are constructed to analyze the results.
This work was supported by Korea Research Foundation Grant (KRF 2001-015-DP0049), the APEC Postdoctoral Fellowships Program,
and the KOSEF Brain Pool Program. 相似文献
24.
The dendrite growth process of transparent NaBi(WO4)2 with small prandtl and high melting point was studied by using the in-situ observation system. According to the dynamic images and detailed information, there are two kinds of restriction effect on
the dendrite growth, the competition between arms and branches and the convection in the melt. The dendrite growth rate was
time dependent, and the rate of arm growth reached the maximum 5.8 mm/s in the diffusive-advective region and rapidly decreased
in the diffusive-convective region. The growth rate of branch had the same change trends as the arm’s. Based on the EPMA-EDS
data of solidification structure of quenched NaBi(WO4)2 melt, it was found that there were component differences from stoichiometric concentration in the melt near the interface
during the growth process.
Supported by the National Natural Science Foundation of China (Grant No. 50331040) and the Innovation Funds from Shanghai
Institute of Ceramics, Chinese Academy of Sciences (Grant No. SCX0623) 相似文献
25.
T. Ramanathan S. Stankovich D. A. Dikin H. Liu H. Shen S. T. Nguyen L. C. Brinson 《Journal of Polymer Science.Polymer Physics》2007,45(15):2097-2112
Mechanical, thermal, and electrical properties of graphite/PMMA composites have been evaluated as functions of particle size and dispersion of the graphitic nanofiller components via the use of three different graphitic nanofillers: “as received graphite” (ARG), “expanded graphite,” (EG) and “graphite nanoplatelets” (GNPs) EG, a graphitic materials with much lower density than ARG, was prepared from ARG flakes via an acid intercalation and thermal expansion. Subsequent sonication of EG in a liquid yielded GNPs as thin stacks of graphitic platelets with thicknesses of ~10 nm. Solution‐based processing was used to prepare PMMA composites with these three fillers. Dynamic mechanical analysis, thermal analysis, and electrical impedance measurements were carried out on the resulting composites, demonstrating that reduced particle size, high surface area, and increased surface roughness can significantly alter the graphite/polymer interface and enhance the mechanical, thermal, and electrical properties of the polymer matrix. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2097–2112, 2007 相似文献
26.
We use the PCP-SAFT equation of state, which is of the Van der Waals type and has a sound physical basis, to predict mixture properties, such as vapor–liquid and liquid–liquid equilibria, as well as excess enthalpies. We use molecular properties, such as dipole moment, quadrupole moment, polarizability and dispersion interaction coefficients, that have been determined quantum mechanically in Part I of this publication and adjust the remaining three pure compound parameters to pure compound data. We finally present a new combination rule for the dispersion energy parameter ? that is based on the quantum mechanically determined data. The predictions based on quantum mechanically determined pure compound properties along with the new combination rule show an improved performance compared to the original PCP-SAFT combination rule. 相似文献
27.
Ngo Quang Huy Trinh Thi Bich Nguyen Van Suc 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(1):129-133
Summary The paper presents a procedure to prepare soil samples for U and Th isotope measurement by alpha-spectrometry after coprecipitation
with LaF3. In this procedure the reduction of U(VI) to U(IV) was performed by Zn metal in 4M HCl solution. The recoveries of chemical
separation equal to eU-chemistry = 78±4% for uranium and eTh-chemistry = 82±4% for thorium. Canberra alpha-spectrometer was used with PIPS detectors of A-1200-37-AM Model of 1200 mm2 active area. The counting efficiency of the measuring system equals to ecounting = 18% and the total efficiencies were eU = ecounting .eU-chemistry = 14.0±0.7% for uranium and eTh = ecounting .eTh-chemistry = 14.7±0.7% for thorium. The recoveries of chemical separation were rather high (about 80%), that leads to the use of a small
weight of soil sample (about 0.5 g). The efficiencies were also stable, that allows analyzing the soil sample without using
radiotracers. They are advantages of the sample preparation procedure of this work. 相似文献
28.
Summary Cold neutrons at the external neutron guide laboratory (ELLA) of the KFA Jülich are used to demonstrate their profitable application
for multielement characterization of biological materials. The set-up and experimental conditions of the Prompt Gamma Cold
Neutron Activation Analysis (PGCNAA) device is described in detail. Results for C, H, N, S, K, B, and Cd using synthetic standards
and the “ratio” technique for calculation are reported for several reference materials and prove the method to be reliable
and complementary with respect to the elements being determined by INAA.
IAEA fellow at the KFA from 6. 3. 91 to 2. 9. 91 on contract No. VIE/9016R. 相似文献
29.
Z. Szeglowski H. Bruchertseifer V. B. Brudanin G. V. Buklanov O. Constantinescu Dinh Thi Lien V. P. Domanov L. I. Guseva M. Hussonnois G. S. Tikhomirova I. Zvara Yu. Ts. Oganessian 《Journal of Radioanalytical and Nuclear Chemistry》1994,186(4):353-359
The short-lived isotopes of W and their descendants have been isolated from the products of the bombardment of144Sm with24Mg by a fast continuous ion-exchange method, using HF solution media. The feasibility of this method for isolation of element 106 is discussed. 相似文献
30.