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91.
GUY BOUCHITTÉ IRENE FONSECA GIOVANNI LEONI LUÍSA MASCARENHAS 《Archive for Rational Mechanics and Analysis》2002,165(3):187-242
An integral representation formula for a class of functionals defined on and in (the space of special functions of bounded variation) is obtained without requiring the regularity conditions usually imposed
in the literature. The approach is based on the general results of [10] and on a Poincaré-Wirtinger type inequality introduced
by DE GIORGI, CARRIERO & LEACI [25]. Applications to relaxation problems and dimension-reduction problems in brittle thin
films are presented.
(Accepted May 8, 2002) Published online October 18, 2002
Communicated by L. Ambrosio 相似文献
92.
Swingle Nunes S. Sulaiman S.B. Sahoo N. Das T.P. Bharuth-Ram K. Frank M. Kreische W. Bonde Nielsen K. 《Hyperfine Interactions》1999,120(1-8):151-155
The Hartree-Fock cluster procedure was used to obtain the associated electronic distributions for 19F* (I = 5/2, E
x
= 197 KeV excited nuclear state of the 19F atom) at possible sites in crystalline Si, Ge and diamond and to calculate nuclear quadrupole coupling constants v
Q
and the asymmetry parameter η of the electric field gradient at the modelled sites. Lattice relaxation effects have been
incorporated by employing a geometry optimization method to obtain minimum energy configurations for the clusters modelling
each site. The intrabond (IB), antibonding (AB) and substitutional (S) sites in the bulk and the atop site on the surface
were studied. From a comparison with v
Q
and η values observed in time differential perturbed angular distribution (TDPAD) measurements we were able to identify the
high frequency component in Si and Ge with 19F* at the intrabond site. In diamond two high frequency components are observed. These are identified with 19F* at intrabond and substitutional sites. For the low frequency site in Si and Ge the assignment is made to 19F* implants at dangling bonds in the bulk resulting from implantation damage. In diamond none of the sites studied could provide
lower frequency nuclear quadrupole parameters close to the observed ones.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
93.
Potential of membrane distillation in seawater desalination: Thermal efficiency,sensitivity study and cost estimation 总被引:1,自引:0,他引:1
Sulaiman Al-Obaidani Efrem Curcio Francesca Macedonio Gianluca Di Profio Hilal Al-Hinai Enrico Drioli 《Journal of membrane science》2008
In this work, an extensive analysis on direct contact membrane distillation (DCMD) performance was developed to estimate the mass flux and the heat efficiency, considering transport phenomena, membrane structural properties and most sensitive process parameters, with the aim to provide optimization guidelines for materials and methods. The results showed that an increase of the temperature gradient resulted in the enhancement of both transmembrane flux and thermal efficiency. The investigation of the effects of membrane properties confirmed that better DCMD performance was achieved when using polymeric membranes characterized by low thermal conductivity (flux and thermal efficiency declined by 26% and 50%, respectively, when increasing thermal conductivity from 0.1 to 0.5 W/m K), and high porosity. An optimal thickness value (around 0.7 mm) was identified when operating at low temperature gradient (<5 °C). However, at higher temperature gradient (>10 °C), increasing the membrane thickness from 0.25 to 1.55 mm resulted in a flux decay of about 70% without a significant improvement in thermal efficiency. 相似文献
94.
For purposes of comparison of the accuracies of the Hartree-Fock Cluster and Discrete Variational Method Cluster procedures
currently in use for investigation of hyperfine properties of solid state systems, we have studied by both procedures the
nuclear quadrupole interactions and silicon-halogen bond distances in the monohalosilane systems SiH3X(X=F, Cl, Br and I). Very good agreement is found between the results by the two procedures and with experiment. 相似文献
95.
The φ meson productions in Au+Au and/or Pb+Pb collisions at AGS, SPS,
RHIC, and LHC energies have been studied systematically with a hadron and
string cascade model LUCIAE. After considering the energy dependence of the
model parameter α in string fragmentation function and adjusting it
to the experimental data of charged multiplicity to a certain extent,
the model predictions for φ meson yield, rapidity, and
transverse mass distributions are compatible with the experimental data at
AGS, SPS and RHIC energies. A calculation for Pb+Pb collisions at LHC energy
is given as well. The obtained fractional variable in string fragmentation
function shows a saturation in energy dependence. It is discussed that the
saturation of fractional variable in string fragmentation function might be a
qualitative representation of the energy dependence of nuclear transparency. 相似文献
96.
A PCR amplification method without DNA extraction 总被引:1,自引:0,他引:1
To develop a simple and inexpensive method for direct PCR amplification of animal DNA from tissues, we optimized different components and their concentration in lysis buffer systems. Finally, we acquired the optimized buffer system composed of 10?mmol tris(hydroxymethyl)aminomethane (Tris)-Cl (pH 8.0), 2?mmol ethylene diamine tetraacetic (EDTA) (pH 8.0), 0.2?mol NaCl and 200?μg/mL Proteinase K. Interestingly, the optimized buffer is also very effective when working with common human sample types, including blood, buccal cells and hair. The direct PCR method requires fewer reagents (Tris-Cl, EDTA, Protease K and NaCl) and less incubation time (only 35?min). The cost of treating every sample is less than $0.02, and all steps can be completed on a thermal cycler in a 96-well format. So, the proposed method will significantly improve high-throughput PCR-based molecular assays in animal systems and in common human sample types. 相似文献
97.
W.T. Sulaiman 《Applied Mathematics Letters》2012,25(3):520-525
We present new kinds of Hardy integral inequalities involving some generalization and improvement. 相似文献
98.
99.
Evidence shows that honey improves glycemic control in diabetes mellitus. Besides its hypoglycemic effect, studies indicate that honey ameliorates lipid abnormalities in rats and humans with diabetes. The majority of these studies do not examine the mechanisms by which honey ameliorates glycemic and/or lipid derangements. The gut microbiota is now recognized for its ability to increase energy harvest from the diet and alter lipid metabolism of the host. Recently available data implicate a causal role of these gut microbes in the pathophysiology of obesity, insulin resistance, and diabetes mellitus. In this review, we present some of the latest findings linking gut microbiota to pathogenesis of obesity, insulin resistance, and diabetes mellitus. The review also underlines data that demonstrate the beneficial effects of oligosaccharides on various abnormalities commonly associated with these disorders. Based on the similarities of some of these findings with those of honey, together with the evidence that honey contains oligosaccharides, we hypothesize that oligosaccharides present in honey might contribute to the antidiabetic and other health-related beneficial effects of honey. We anticipate that the possibility of oligosaccharides in honey contributing to the antidiabetic and other health-related effects of honey will stimulate a renewed research interest in this field. 相似文献
100.
M. Rafatullah O. Sulaiman R. Hashim M. H. M. Amini 《Journal of Dispersion Science and Technology》2013,34(11):1641-1648
Il palm leaf powder (OPLP), an agricultural solid waste was used as adsorbent for the removal of copper (II) ions after modification with an anionic surfactant, sodium dodecyl benzene sulfonate (SDBS), CH3(CH2)11C6H4SO3Na. The copper (II) ions adsorption is highly dependent on pH and maximum removal was observed at pH 6, above which copper (II) started to precipitate. The equilibrium adsorption data were fitted into the Langmuir and Freundlich isotherms. The Freundlich isotherm model fitted well to data with 0.989 regression coefficient (R2). The kinetics of the adsorption of copper (II) ions onto the surfactant-modified OPLP was best described by a pseudo-second-order model. Comparison of this SDBS-modified-OPLP to previously investigated adsorbents showed comparably good result, offering this material as a promising adsorbent for the treatment of waste waters containing lower concentrations of copper (II) ions. 相似文献