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1.
Victor Pambuccian 《Mathematical Logic Quarterly》1992,38(1):345-348
We proved in the first part [1] that plane geometry over Pythagorean fields is axiomatizable by quantifier-free axioms in a language with three individual constants, one binary and three ternary operation symbols. In this paper we prove that two of these operation symbols are superfluous. 相似文献
2.
M. Paluch 《Colloid and polymer science》1998,276(7):648-652
The results of experimental studies of the adsorption at the solution/air interface from an aqueous mixture: 2,4,6-trimethylphenol–2,4,6-trichlorophenol
are presented. The surface properties of the above-mentioned mixture were studied by surface potential and surface tension
measurements. These measurements were carried out as a function of the concentration of 2,4,6-trimethylphenol aqueous solution
at a constant concentration of 2,4,6-trichlorophenol.
Using the results obtained and based on the Gibbs equation, Helmholtz formula and Motomura’s method the relative surface excesses
of adsorbed substances, effective dipole moments, surface molar fractions of solutes and miscibility of adsorbed films were
determined.
Received: 7 November 1997 Accepted: 26 February 1998 相似文献
3.
《Journal of Coordination Chemistry》2012,65(2):165-173
The title complex has been synthesized and characterized by elemental and thermal analysis, IR and electronic spectroscopy, conductivity studies and X-ray crystallography. In the crystal, the complex has two-fold symmetry and the copper atom adopts square pyramidal coordination. Bond valences for Cu were computed. Cu–O(propionate) bonds are slightly stronger than the Cu–N bonds, and the Cu–O(water) bond is distinctly weaker. Molecules are linked by O–H···O hydrogen bonds to form infinite hydrogen-bonded chains along the y axis. 相似文献
4.
J. Anandan 《Foundations of Physics Letters》1993,6(6):503-532
It is shown that from the expectation values of obervables, which can be measured for a single system using protective measurements, the linear structure, inner product, and observables in the Hilbert space can be reconstructed. A universal method of measuring the wave function of a single particle using its gravitational field is given. Protective measurement is generalized to the measurement of a degenerate state and to many particle systems. The question of whether the wave function is real is examined, and an argument of Einstein in favor of the ensemble interpretation of quantum theory is refuted. 相似文献
5.
In 2005, Zhang presented a Grubin-like inlet zone analysis to the isothermal line contact elastohydrodynamic lubrication under relatively heavy loads when the hydrodynamic film thickness in the Hertzian zone approaches zero and the EHL fluid is Newtonian [Zhang, Y.B. A justification of the load-carrying capacity of elastohydrodynamic lubrication film based on the Newtonian fluid model. Industrial Lubrication and Tribology, 2005, Vol. 57, pp. 224–232]. His results showed that in this EHL, when the rolling speed is lower than the characteristic rolling speed (Uch =) 0.0372W1.50/G, the Hertzian zone is in physical adsorbed layer boundary lubrication while the inlet zone is in conventional hydrodynamic lubrication. This mode of EHL represents a mode of mixed EHL with mixed contact regimes, where hydrodynamic films with different rheological behaviors occur in different areas of the contact. The present paper presents an analysis to this mode of mixed EHL by using the Grubin type method when the contact adhering layer in the inlet zone is neglected. Pressures, film thicknesses and load partition in the contact are obtained from this analysis. It is also found that the formula for the characteristic rolling speed Uch = 0.0372W1.50/G obtained by Zhang [Zhang, Y.B. A justification of the load-carrying capacity of elastohydrodynamic lubrication film based on the Newtonian fluid model. Industrial Lubrication and Tribology, 2005, Vol. 57, pp. 224–232] may be valid for the dimensionless load W > 1.0E−7, while it may be invalid for the dimensionless load W < 1.0E−8. In part II [Zhang, Y.B. Analytical solution to a mode of mixed elastohydrodynamic lubrication with mixed contact regimes: Part II. Considering the contact adhering layer effect in the inlet zone. Journal of Molecular Liquids, 2006, Vol. 117. (doi:10.1016/j.molliq.2006.04.007)] will be presented an analysis to other two modes of mixed EHL with mixed contact regimes for relatively heavy loads, low rolling speeds and Newtonian fluids, where the conventional hydrodynamic lubrication, physical adsorbed layer boundary lubrication and oxidized chemical layer boundary lubrication can simultaneously occur in the inlet zone while the oxidized chemical layer boundary lubrication or the fresh metal-oxidized chemical boundary layer dry contact occur in the Hertzian zone, considering the contact adhering layer effect in the inlet zone. 相似文献
6.
The magnetization of mixed spin-1/2, 1 Ising diamond chain with antiferromagnetic spin exchange interaction has been investigated by using the Monte Carlo simulation. Magnetization behaviors with different antiferromagnetic interactions are simulated under magnetic field at low temperature. The behaviors are studied in two different cases. In one case the absolute value of the interaction between two spin-1/2 atoms is the largest and in the other case it is not the largest. Multiple plateaus of magnetization M, such as plateaus at M=±1, M=0 and M=±0.566 are obtained. The plateaus at M=±0.566 correspond to two metastable states. The M=0 plateau may disappear at some specific values of spin exchange interactions. The spin configurations were checked when the plateaus appear. The dimmer and trimmer states are found. 相似文献
7.
We present a definition of Riemannian manifold in noncommutative geometry. Using products of unbounded Kasparov modules, we show one can obtain such Riemannian manifolds from noncommutative spinc manifolds; and conversely, in the presence of a spinc structure. We also show how to obtain an analogue of Kasparov’s fundamental class for a Riemannian manifold, and the associated notion of Poincaré duality. Along the way we clarify the bimodule and first-order conditions for spectral triples. 相似文献
8.
Carmen Moldovan Carmen Mihailescu Dana Stan Lavinia Ruta Rodica Iosub Raluca Gavrila Munizer Purica Schiopu Vasilica 《Applied Surface Science》2009,255(22):8953-8959
This article presents the characterization of two substrates, silicon and polymer coated with gold, that are functionalized by mixed self-assembled monolayers (SAMs) in order to efficiently immobilize the anti-Escherichia coli O157:H7 polyclonal purified antibody.A biosurface functionalized by SAMs (self-assembled monolayers) technique has been developed. Immobilization of goat anti-E. coli O157:H7 antibody was performed by covalently bonding of thiolate mixed self-assembled monolayers (SAMs) realized on two substrates: polymer coated with gold and silicon coated with gold. The F(ab′)2 fragments of the antibodies have been used for eliminating nonspecific bindings between the Fc portions of antibodies and the Fc receptor on cells. The properties of the monolayers and the biofilm formatted with attached antibody molecules were analyzed at each step using infrared spectroscopy (FTIR-ATR), atomic force microscopy (AFM), scanning electron microscopy (SEM) and cyclic voltammetry (CV). In our study the gold-coated silicon substrates approach yielded the best results.These experimental results revealed the necessity to investigate each stage of the immobilization process taking into account in the same time the factors that influence the chemistry of the surface and the further interactions as well and also provide a solid basis for further studies aiming at elaborating sensitive and specific immunosensor or a microarray for the detection of E. coli O157:H7. 相似文献
9.
Single-component monolayer of novel multi-thiol coronary molecule and two-component mixed monolayer composed of coronary molecule and n-alkanethiol on gold substrates are described. The assembly of monolayers is characterized by ellipsometry, infrared spectroscopy and X-ray photoelectron spectroscope. The electrochemical properties of the single- and two-component monolayers are evaluated by cyclic voltammetry and electrochemical impedance spectroscopy experiments. Coronary molecule with multi-thiol groups has the ability to form stable monolayer via the interaction of mercapto groups and Au surface. Electrochemical impedance measurements indicate that 89.9% of the gold surface is blocked by the coronary molecule, which is attributed to the special spatial structure of the coronary molecule. The uncovered site on gold surface in coronary molecule monolayer could be occupied by the second suitable molecule. The mixed monolayer prepared by stepwise assembly of coronary molecule and n-alkanethiol has complete compact packing and few defects. 相似文献
10.
Stimulated infrared (IR) emission from a condensed dielectric medium under exposure to a giant pulse of a ruby laser is reported.
This effect was predicted in the theoretical paper [1]. Experimental studies were carried out for a number of molecular liquids
in two experimental geometries. In the first case (“in transmission” geometry) the propagation direction of the detected IR
radiation coincided with that of the exciting radiation. In the second case IR radiation generated was detected in the opposite
direction. The angle of divergence of IR radiation was found to be of 10−2 rad, while the conversion efficiency with respect to the pumping intensity depended on the type of molecular liquid and varied
in the range of 0.05–0.6%. Possible microscopic mechanisms of generation of IR radiation under pumping of the dielectric medium
with visible or ultraviolet (UV) radiation are analyzed. 相似文献