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721.
Rym Chemmam Habib Mâagli Syrine Masmoudi 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(5):1555-1576
The purpose of this paper is to extend some results of the potential theory of an elliptic operator to the fractional Laplacian (−Δ)α/2, 0<α<2, in a bounded C1,1 domain D in Rn. In particular, we introduce a new Kato class Kα(D) and we exploit the properties of this class to study the existence of positive solutions of some Dirichlet problems for the fractional Laplacian. 相似文献
722.
A sensitive hydrogen peroxide (H2O2) biosensor was developed based on a reduced graphene oxide|carbon ceramic electrode (RGO|CCE) modified with cadmium sulfide‐hemoglobin (CdS‐Hb). The electron transfer kinetics of Hb were promoted due to the synergetic function of RGO and CdS nanoparticles. The transfer coefficient (α) and the heterogeneous electron transfer rate constant (ks) were calculated to be 0.54 and 2.6 s?1, respectively, indicating a great facilitation achieved in the electron transfer between Hb and the electrode surface. The biosensor showed a good linear response to the reduction of H2O2 over the concentration range of 2–240 µM with a detection limit of 0.24 µM (S/N=3) and a sensitivity of 1.056 µA µM?1 cm?2. The high surface coverage of the CdS‐Hb modified RGO|CCE (1.04×10?8 mol cm?2) and a smaller value of the apparent Michaelis? Menten constant (0.24 mM) confirmed excellent loading of Hb and high affinity of the biosensor for hydrogen peroxide. 相似文献
723.
In this article, we review the concept of a Lévy copula to describe the dependence structure of a bivariate compound Poisson process. In this first statistical approach we consider a parametric model for the Lévy copula and estimate the parameters of the full dependent model based on a maximum likelihood approach. This approach ensures that the estimated model remains in the class of multivariate compound Poisson processes. A simulation study investigates the small sample behaviour of the MLEs, where we also suggest a new simulation algorithm. Finally, we apply our method to Danish fire insurance data. 相似文献
724.
725.
726.
Bakthavatchalam Balaji Habib Khairul Wilfred Cecilia D. Saidur R. Saha Bidyut Baran 《Journal of Thermal Analysis and Calorimetry》2022,147(1):393-408
Journal of Thermal Analysis and Calorimetry - Conventional surfactants such as CTAB (cetrimonium bromide), SDS (sodium dodecyl sulphate), SDBS (sodium dodecyl sulphonate) are combined with... 相似文献
727.
Habib Ghobarkar 《Crystal Research and Technology》1992,27(4):451-456
In this investigation the Petalite minerals were synthesized hydrothermally at different temperatures from a glass with the composition Li2CO3:Al2O3: SiO2 and the relation 1: 1: 8. On that occasion the following mineral phases arised:
- at low temperatures (410°C) α-petalite (unit cell å = 11.737 Å/b̊ = 5.17 Å/c̊ = 7.63 Å, space group P2/a);
- At 490 °C α-petalite was splitted to quartz and an orthorhombic β1-petalite (unit cell å = 18.24 Å/c̊ = 10.54 Å/c̊ = 10.57 Å, space group PmCn). β1-petalite could be observated until 1000 °C.
- at 560 °C tetragonal β2-petalite (unit cell å = 7.50 Å/c̊ = 9.07 Å, space group P 43212) in parallel with β1-petalite;
- Behind 750 °C β2-petalite was not observed.
- Behind 900 °C a pseudohexagonal mineral phase developed from β1-petalite. May be it is possible to indicate this phase as hexagonal (unit cell å = 5.217 Å/c̊ = 5.464 Å, space group P 6222 or P 6422). The author suggests to denote this phase as β3-petalite.
728.
Lithiumcarbonat was treated hydrothermally in the range of temperature from 80 °C to 600 °C. The Li2CO3-crystals of the starting material were monoclinic with the unit cell a = 8.39 Å, b = 5.00 Å, c = 6.21 Å, β = 114.5° and the space group C2/c (Zemann). During the increase of temperature the habit of the Li2CO3-crystals changed in the ranges of higher temperatures that they could be described as pseudocubic. In parallel with this development the electrical conductivity of the crystals also changed. 相似文献
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730.
Habib Ghobarkar 《Crystal Research and Technology》1992,27(2):181-185
The hydrothermal treatment of glass with the composition 2 LiF, Al2O3, 3 SiO2 at 1 kbar in the range of 150 °C to 850 °C gave rise to the formation of A-zeolite with orthorhombic unit cell with å = 10.31 Å/b̊ = 8.18 Å/c̊ = 5.0 Å (space group Pna21), α-eucryptite, trigonal, å = 13.4 Å/bº = 13.4/Å/cº = 9.0 Å (space group R 3 ), β-spodumene, pseudocubic/tetragonal, å = 7.53 Å/b̊ = 7.53 Å/c̊ = 9.15 Å (space group P43212), β-eucryptite, monoclinic, å = 7.75 Å/b̊ = 5.2 Å/c̊ = 11.16 Å (space group P6222). The morphology and development of the mineral phases depend on the temperature of formation. 相似文献