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Davar A. Azarafza R. Fayez M. S. Fallahi S. Jam J. E. 《Mechanics of Composite Materials》2021,57(2):181-204
Mechanics of Composite Materials - Equilibrium equations of a rib grid-stiffened composite cylindrical shell reinforced with carbon nanotubes (CNTs) are derived based on the first-order shear... 相似文献
13.
Summary Sufficient conditions are given for a family of local times |L
t
µ
| ofd-dimensional Brownian motion to be jointly continuous as a function oft and . Then invariance principles are given for the weak convergence of local times of lattice valued random walks to the local times of Brownian motion, uniformly over a large family of measures. Applications included some new results for intersection local times for Brownian motions on 2 and 2.Research partially supported by NSF grant DMS-8822053 相似文献
14.
Gharagozlou M Boghaei DM 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(4):1617-1622
Fluorescence spectroscopy in combination with circular dichroism (CD) spectroscopy were used to investigate the interaction of water-soluble amino acid Schiff base complexes, [Zn(L1,2)(phen)] where phen is 1,10-phenanthroline and H2L1,2 is amino acid Schiff base ligands, with bovine serum albumin (BSA) under the physiological conditions in phosphate buffer solution adjusted to pH 7.0. The quenching mechanism of fluorescence was suggested as static quenching according to the Stern-Volmer equation. Quenching constants were determined using the Stern-Volmer equation to provide a measure of the binding affinity between amino acid Schiff base complexes and BSA. The thermodynamic parameters DeltaG, DeltaH and DeltaS at different temperatures (298, 310 and 318K) were calculated. The results indicate that the hydrophobic and hydrogen bonding interactions play a major role in [Zn(L1)(phen)]-BSA association, whereas hydrophobic and electrostatic interactions participate a main role in [Zn(L2)(phen)]-BSA binding process. Binding studies concerning the number of binding sites and apparent binding constant Kb were performed by fluorescence quenching method. The distance R between the donor (BSA) and acceptor (amino acid Schiff base complexes) has been obtained utilizing fluorescence resonant energy transfer (FRET). Furthermore, CD spectra were used to investigate the structural changes of the BSA molecule with the addition of amino acid Schiff base complexes. The results indicate that the interaction of amino acid Schiff base complexes with BSA leads to changes in the secondary structure of the protein. Fractional contents of the secondary structure of BSA (f(alpha), f(beta), f(turn) and f(random)) were calculated with and without amino acid Schiff base complexes utilizing circular dichroism spectroscopy. Our results clarified that amino acid Schiff base complexes could bind to BSA and be effectively transported and eliminated in the body, which could be a useful guideline for further drug design. 相似文献
15.
Mohammad Mahdi Najafpour Davar M. Boghaei Per J.R. Sjöberg 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):1168-1170
The mononuclear complex [Mn(tptz)(CH3COO)(OH2)2]NO3 (1) was investigated by electrospray ionization mass spectrometry in aqueous solution at pH 4.5. Electrospray ionization mass spectrometry shows that mononuclear and dinuclear manganese cationic species are present in solution, probably in equilibrium with neutral 1. An experiment showed that the most important reaction in the presence of oxone (2KHSO5·KHSO4·K2SO4) is decoordination. 相似文献
16.
Davar Khoshnevisan Yimin Xiao 《Proceedings of the American Mathematical Society》2003,131(8):2611-2616
A probability measure on is called weakly unimodal if there exists a constant such that for all 0$">,
Here, denotes the -ball centered at with radius 0$">.
(0.1) |
Here, denotes the -ball centered at with radius 0$">.
In this note, we derive a sufficient condition for weak unimodality of a measure on the Borel subsets of . In particular, we use this to prove that every symmetric infinitely divisible distribution is weakly unimodal. This result is then applied to improve some recent results of the authors on capacities and level sets of additive Lévy processes.
17.
Synthesis and characterization of metallic copper nanoparticles via thermal decomposition 总被引:1,自引:0,他引:1
Copper oxalate was used as a precursor to prepare metallic copper nanoparticles by thermal decomposition. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and UV–Vis spectroscopy. XRD analysis revealed broad pattern for fcc crystal structure of copper metal. The particle size by use of Debye–Scherrer’s equation was calculated to be about 40 nm. 相似文献
18.
Major blood anticlotting agents may be grouped into two classes: 1) heparin and heparin analogs, 2) coumarin and coumarin analogs. The first class of compounds interferes with the formation of thrombin and thromboplastin whereas the second inhibits the formation of prothrombin. Both classes have their own antagonists; namely, protamine sulfate types and vitamin K types exhibiting antihemorrhagic properties. On a molecular level the heparinlike structures and their antagonists may be regarded as polyanions and polycations, respectively, whereas the coumarinlike structures and their antagonists as electron donors and acceptors, respectively, which may form charge transfer complexes. 相似文献
19.
The standard free energy change for complex formation is written as a sum of effects arising from solvent-solvent interactions (the general medium effect), solvent-solute interactions (the solvation effect), and solute-solute interactions (the intersolute effect). The general medium effect is given by gA(–o), where g is a curvature correction factor to the solvent surface tension , A is the change in surface area as the two solvent cavities containing the substrate (naphthalene) and ligand (theophylline) collapse into a single cavity containing the complex, and o is the value of surface tcnsion at which there is no net solvophobic interaction; is defined to be the value appropriate to the equilibrium mean solvation shell composition. The solvation effect is modeled by equilibrium stoichiometric formation of solvated species. All data are related to the fully aqueous system to give MGo, the solvent effect on the free energy change, as an explicit function of solvent composition. Solvent effects on bimolecular association are related to solvent effects on the solubilities of the substrate, ligand, and complex. Approximation methods for interpreting such systems are described and are applied to the naphthalene-theophylline complex. It is shown that complex destabilization in mixed aqueous-organic solvents (relative to the fully aqueous system) may receive contributions from both the general medium and the solvation effects, and that these contributions can be quantitatively estimated. 相似文献
20.
Davar Khoshnevisan Narn-Rueih Shieh Yimin Xiao 《Probability Theory and Related Fields》2008,140(1-2):129-167
Let X
1, ..., X
N
denote N independent, symmetric Lévy processes on R
d
. The corresponding additive Lévy process is defined as the following N-parameter random field on R
d
:
Khoshnevisan and Xiao (Ann Probab 30(1):62–100, 2002) have found a necessary and sufficient condition for the zero-set of to be non-trivial with positive probability. They also provide bounds for the Hausdorff dimension of which hold with positive probability in the case that can be non-void.
Here we prove that the Hausdorff dimension of is a constant almost surely on the event . Moreover, we derive a formula for the said constant. This portion of our work extends the well known formulas of Horowitz
(Israel J Math 6:176–182, 1968) and Hawkes (J Lond Math Soc 8:517–525, 1974) both of which hold for one-parameter Lévy processes.
More generally, we prove that for every nonrandom Borel set F in (0,∞)
N
, the Hausdorff dimension of is a constant almost surely on the event . This constant is computed explicitly in many cases.
The research of N.-R. S. was supported by a grant from the Taiwan NSC. 相似文献