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991.
The risks and returns of stock investment are discussed via numerically simulating the mean escape time and the probability density function of stock price returns in the modified Heston model with time delay. Through analyzing the effects of delay time and initial position on the risks and returns of stock investment, the results indicate that: (i) There is an optimal delay time matching minimal risks of stock investment, maximal average stock price returns and strongest stability of stock price returns for strong elasticity of demand of stocks (EDS), but the opposite results for weak EDS; (ii) The increment of initial position recedes the risks of stock investment, strengthens the average stock price returns and enhances stability of stock price returns. Finally, the probability density function of stock price returns and the probability density function of volatility and the correlation function of stock price returns are compared with other literatures. In addition, good agreements are found between them. 相似文献
992.
N. Pongali Sathya Prabu 《Phase Transitions》2013,86(7):592-607
In this study, complexes belonging to supramolecular hydrogen-bonded liquid crystal homologous series are synthesized and characterized. Hydrogen bond is formed between p-n-alkyloxy benzoic acids (nBAO, where n?=?5–11) and chlorobenzoic acid (ClBAO), respectively. The isolated homologues are characterized by various techniques such as polarizing optical microscopic (POM) studies, differential scanning calorimetry (DSC), and Fourier transform–infrared spectroscopy. Based on the POM and DSC studies, the phase diagram has been constructed and discussed. A new smectic ordering, labeled as smectic R, has been characterized, which exhibits a ribbon-like texture. This phase is observed in the complexes pertaining to the higher homologous series. Tilt angle in this phase has been experimentally deduced and the results are fitted to the power law which concurs with the mean-field theory predicted value. Optical shuttering action in the homologue has been detected in the nematic phase and the results are also discussed. 相似文献
993.
Abstract The fluoroapatite minerals, Ca5-F(PO4)3 usually contain some hydroxyis, instead of fluorine. From infrared spectra it was concluded, that there are weak hydrogen bonds OH … F along apatite hexagonal axis1. In order to receive more detailed information about the character of F?and OH?bonds with the nearest atoms in apatites we studied the nuclear magnetic resonance (NMR) spectra of protons and fluorines in natural apatite single crystal, in which approximately 15% of fluorines is substituted by hydroxyis. 相似文献
994.
R. W. Miller 《光谱学快报》2013,46(12):895-910
Fusarium sulphureum is an important fungus belonging to a group of pathogenic Ascomycetes which cause root and vascular disease in cereal and vegetable crops. These organisms ordinarily grow as vegetative hyphae but under unfavorable conditions form macroconidia and chlamydospores as dispersal and survival propagules. The role of compositional and physical changes in cellular membranes during growth, survival and propagation of the pathogen provides the focus of this investigation. 相似文献
995.
Mehdi D. Esrafili Parisasadat Mousavian Fariba Mohammadian-Sabet 《Molecular physics》2013,111(6):726-733
ABSTRACTThe aim of this study is to investigate the influence of a hydrogen- or lithium-bonding interaction on the cooperativity of chalcogen bonds in linear NCH···(OCX)2–5 and NCLi···(OCX)2-5 clusters (X?=?S, Se). The nature of interactions in the optimised structures is analysed by means of molecular electrostatic potential, quantum theory of atoms in molecules, natural bond orbital and electron density difference methods. According to our results, the formation of a lithium-bonding interaction in NCLi···(OCX)2-5 clusters induces a large increase in the strength of X···O chalcogen bonds, and hence their cooperativity. This can be mainly rationalised in terms of the electrostatic nature of chalcogen bonds as well as the fundamental orbital interaction between the interacting OCX subunits. The results of this study provide a theoretical evidence for the tuning of chalcogen bonds cooperativity by a hydrogen- or lithium-bonding. 相似文献
996.
We investigate the continuity of expected exponential utility maximization with respect to perturbation of the Sharpe ratio of markets. By focusing only on continuity, we impose weaker regularity conditions than those found in the literature. Specifically, we require, in addition to the V-compactness hypothesis of Larsen and ?itkovi? (2007) [13], a local bmo hypothesis, a condition which is essentially implicit in the setting of [13]. For markets of the form S=M+∫λd〈M〉, these conditions are simultaneously implied by the existence of a uniform bound on the norm of λ⋅M in a suitable bmo space. 相似文献
997.
We address risk minimizing option pricing in a regime switching market where the floating interest rate depends on a finite state Markov process. The growth rate and the volatility of the stock also depend on the Markov process. Using the minimal martingale measure, we show that the locally risk minimizing prices for certain exotic options satisfy a system of Black-Scholes partial differential equations with appropriate boundary conditions. We find the corresponding hedging strategies and the residual risk. We develop suitable numerical methods to compute option prices. 相似文献
998.
Davar M. Boghaei Fatemeh Behzadian-Asl Hamid Reza Khavasi 《Journal of chemical crystallography》2008,38(4):311-314
Abstract The chemical preparation and crystal structure for a 4,4′-azodi(phenylcyanamide) salt) in the solid state are reported. This
compound crystallizes in the triclinic space group P
with the following unit cell parameters: a = 9.759(3) ?, b = 11.237(4) ?, c = 11.919(4) ?, α = 95.54(3)°, β = 98.50(3)°, γ = 109.39(2)°, Z = 1 and V = 1204.4(7) ?3. The 4,4′-azodi(phenylcyanamide) dianion, azodicyd2−, is approximately planar, with the cyanamide groups (–N=C=N) in an anti conformation relative to each other and the azo group (–N=N–) adopting the more thermodynamically stable trans conformation. The crystal X-ray analysis shows that there are one azo molecule cation, two tetrabutylammonium cations and
one water molecule in unit cell. Intermolecular O–H···N hydrogen bonds may be effective in the stabilization of the crystal
structure of this compound and to form linear chain structure in the packing.
Index Abstract Synthesis and crystal structure of Bis (Tetrabutylammonium)(4,4′-Azodi(phenylcyanamide)) salt . [(n-Bu)4N]2[Azodicyd2-] · H2O
Davar M. Boghaei 1*, Fatemeh Behzadian-Asl 1 and Hamid Reza Khavasi2
1 Department of Chemistry, Sharif University of Technology, P.O. Box 11155-9616, Tehran, Iran
2 Department of Chemistry, Shahid Beheshti University, Evin, Tehran 1983963113, Iran
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
999.
Abstract 7,4′-bis-(hydroxyl)-8,3′,5′-tris-(hydroxymethyl)isoflavone (I) and its ester were synthesized and examined by IR, element
analysis and 1H NMR. The crystal of 7,4′-bis-(acetyl oxide)-8,3′,5′-tris-(acetoxymethyl)isoflavone (II) was studied by X-ray diffraction.
(II) crystallizes in the monoclinic with space group P2
1
/c. a = 17.987(3) ?, b = 17.972(3) ?, c = 8.4087(11) ?, β = 97.703(3)°, V = 2693.7(6) ?3 and Z = 4. The molecular structure of the ester consists of a benzopyranone moiety, a phenyl moiety, two acetyl oxides and three
acetoxymethyl groups. Hydrogen bonds and aromatic stacking interactions link the ester into a two-dimensional structure.
Index Abstract 7,4′-bis-(hydroxyl)-8,3′,5′-tris-(hydroxymethyl)isoflavone and its ester were synthesized and examined by IR, element analysis
and 1H NMR. The result of the ester’s crystal structure showed that hydrogen bonding and aromatic π–π stacking assemble the ester
into a two-dimensional networking structure.
相似文献
1000.
Abstract A new dinuclear hydrated nickel(II) tartrate has been isolated and structurally characterized by single-crystal X-ray diffraction.
The title compound formulated as [Ni4(C4H4O6)4(H2O)8](EtOH)0.5(H2O)10.25 (C17H55.5Ni4O42.75) crystallizes in monoclinic system, space group P2(1)/c with a = 13.684(5), b = 17.143(6), c = 18.586(6) ?, β = 96.638(6)°, V = 4331(3) ?3, Z = 4. The unit cell contains two crystallographic independent dimeric units of [Ni2(C4H4O6)2(H2O)4] without significant structural difference, half of menthol molecule and ten and a quarter packing water molecules. In each
dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms,
and another tartrato dianion chelates the same pair of Ni(II) cations in the same way. Each Ni(II) atom is six-coordinated
by six O atoms from two tartrate units and two water molecules.
Index Abstract The crystal structure of complex [Ni4(C4H4O6)4(H2O)8](EtOH)0.5(H2O)10.25 contains two crystallographic independent dimeric units of [Ni2(C4H4O6)2(H2O)4] without significant structural difference. In each dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms,
and another tartrato dianion chelates the same pair of Ni(II) cations in the same way.
相似文献