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181.
Hakala M Marushkevich K Khriachtchev L Hämäläinen K Räsänen M 《The Journal of chemical physics》2011,134(5):054506
Crystalline formic acid (FA) is studied experimentally and by first-principles simulations in order to identify a bulk solid structure composed of the higher-energy (cis) conformer. In the experiments, deuterated FA (HCOOD) was deposited in a Ne matrix and transformed to the cis conformer by vibrational excitation of the ground state (trans) form. Evaporation of the Ne host above 13 K prepared FA in a bulk solid state mainly composed of cis-FA. Infrared absorption spectroscopy at 4.3 K shows that the obtained solid differs from that composed of trans-FA molecules and that the state persists up to the annealing temperature of at least 110 K. The first-principles simulations reveal various energetically stable periodic chain structures containing cis-FA conformers. These chain structures contain either purely cis or both cis and trans forms. The vibrational frequencies of the calculated structures were compared to the experiment and a tentative assignment is given for a novel solid composed of cis-FA. 相似文献
182.
Experimental observation of strongly bound dimers of sulfuric acid: application to nucleation in the atmosphere 总被引:1,自引:0,他引:1
Petäjä T Sipilä M Paasonen P Nieminen T Kurtén T Ortega IK Stratmann F Vehkamäki H Berndt T Kulmala M 《Physical review letters》2011,106(22):228302
Sulfuric acid is a key compound in atmospheric nucleation. Here we report on the observation of a close-to-collision-limited sulfuric acid dimer formation in atmospherically relevant laboratory conditions in the absence of measurable quantities of ammonia or organics. The observed dimer formation rate was clearly higher than the measured new particle formation rate at ~1.5 nm suggesting that the rate limiting step for the nucleation takes place after the dimerization step. The quantum chemical calculations suggested that even in the ultraclean conditions there exist (a) stabilizing compound(s) with (a) concentration(s) high enough to prevent the dimer evaporation. Such a stabilizing compound should be abundant enough in any natural environment and would therefore not limit the formation of sulfuric acid dimers in the atmosphere. 相似文献
183.
We say that groups, which are isomorphic to inner mapping groups of finite loops, are loop capable. Let p and q be distinct prime numbers, S a nonabelian group of order pq, and C a finite nontrivial cyclic group such that gcd (|S|, |C|) = 1. We show that the group S × C is not loop capable. 相似文献
184.
Markku Miettinen 《Applicable analysis》2013,92(3-4):303-326
We prove the existence of a solution of a constrained hemivariational inequality, and, develop a fully discrete approximation of it. The relation between the constrained hemivariational inequality and a problem of finding substationary points of the corresponding potential function is also studied. 相似文献
185.
Jukka Antikainen Mikael von und zu Fraunberg Joni Orava Juha E. Jaaskelainen Markku Hauta-Kasari 《Optical Review》2011,18(6):458-461
It has been noticed that spectral information can be used for analyzing and separating different biological tissues. However,
most of the studies for spectral image acquisitions are mainly done in vitro. Usually the main restrictions for in vivo measurements are the size or the weight of the spectral camera. If the camera weights too much, the surgery microscope cannot
be stabilized. If the size of the camera is too big, it will disturb the surgeon or even risk the safety of the patient. The
main goal of this study was to develop an independent spectral imaging device which can be used for collecting spectral information
from the neurosurgeries without any previously described restrictions. Size of the imaging system is small enough not to disturb
the surgeon during the surgery. The developed spectral imaging system is used for collecting a spectral database which can
be used for the future imaging systems. 相似文献
186.
Beckenbach and Radó characterized logarithmically subharmonic functions in the plane in terms of integral inequalities involving spherical averages. In this work we generalize this result to higher dimensions and thus answer to a question raised by Beckenbach and Radó. We also consider generalizations of integral inequalities suggested by Beckenbach and Radó and discuss connections to reverse Hölder inequalities and Muckenhoupt weights. 相似文献
187.
Employing stochastic programming, we provide a general framework for option pricing based on marginal bid/ask price valuation.
It is applied to numerical analysis of options with European and American style exercise using a double binary tree. Incentive
options are valued considering hedging restrictions and other market frictions, such as transaction and short position costs,
and different borrowing and lending rates. The framework also includes correlated labor income. The possibility of partial
sales is analyzed using ask price functions. Without friction costs and labor income, our model is the discrete-time equivalent
of Ingersoll (J Bus 79:453–487, 2006). When labor income and/or market frictions are present, or a fraction of options is
sold, the option values are materially different compared to Ingersoll (J Bus 79:453–487, 2006).
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
188.
Susan Kunnas‐Hiltunen Elina Laurila Matti Haukka Jouko Vepsäläinen Markku Ahlgrén 《无机化学与普通化学杂志》2010,636(5):710-720
Four new cobalt, manganese, and copper bis(phosphonates), [Co2{Cl2C(PO3)2}(H2O)7 · 4H2O] ( 1 ), [Co{Cl2C(PO2O(C(O)C6H5))2(H2O)5} · 2H2O{Cl2C(PO2O(C(O)C6H5))2}{Co(H2O)6}] ( 2 ), [Mn{[Cl2C(PO2O(C(O)C6H5))2](H2O)3}] ( 3 ), and [Cu{(CH2C5H5N)C(OH)(PO3H)2}2 · 4H2O] ( 4 ), were prepared by gel, liquid, and evaporation crystallisation methods. Compounds 1 – 4 were characterised by X‐ray single‐crystal diffraction, elemental analysis, infrared spectroscopy, and thermogravimetric analysis. The effects of metal and various substituted groups in bis(phosphonate) ligands on the structure formation of bis(phosphonates) were studied. In the structure of 1 , the clodronic acid ligand ( L1 ) is in bischelating bonding mode, and the dinuclear units of 1 are surrounded by two‐dimensional water cluster patterns. The hydrogen bond network of compound 1 is extended to a three‐dimensional framework when the phosphonate oxygen atoms serve as hydrogen‐bond acceptors. In complex 2 , the CoO6 octahedron shares a corner of one PCO3 tetrahedron of the dibenzoyl derivative of clodronic acid ligand ( L2 ), and forms a two‐dimensional hydrogen bonding network, which consists of [Co(H2O)6}]2+ cations, lattice water molecules and L2 ligand molecules. Compound 3 , in turn, consists of dimeric building blocks built up of PCO3 tetrahedra of the ligand L2 , which connect the corner‐sharing MnO6 octahedra and form an overall 2D structure through hydrogen bonds of coordinated and crystal water molecules and phosphonate oxygen atoms. Complex 4 is among the first metal complexes of risedronic acid ( L3 ). In compound 4 , two L3 ligand molecules chelate tridentately the CuII atom at the center of symmetry, and the monomeric units of 4 are connected to a 3D structure through hydrogen bonding of coordinated and lattice water molecules to both protonated and deprotonated phosphonate oxygen atoms and protonated nitrogen atoms in the pyridine ring. 相似文献
189.
It was recently suggested that the error with respect to experimental data in nuclear mass calculations is due to the presence of chaotic motion. The theory was tested by analyzing the typical error size. A more sensitive quantity, the correlations of the mass error between neighboring nuclei, is studied here. The results provide further support to this physical interpretation. 相似文献
190.
We show that in a typical sub-self-affine set, the Hausdorff and the Minkowski dimensions coincide and equal the zero of an
appropriate topological pressure. This gives a partial positive answer to the question of Falconer. We also study the properties
of the topological pressure and the existence and the uniqueness of natural measures supported on a sub-self-affine set. 相似文献