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11.
The effects of radiofrequency (RF) (1–4) and magnetic fields (5–9) on the behavior of aqueous solutions and suspensions have been a popular subject in recent years. The mechanism of the magnetic “water memory” effect, though, is still largely unknown (5). In this work, we present evidence that the primary “receptor” of the electromagnetic radiation is a gas/liquid interface. Gas can be either already present in water or produced by the effects of electromagnetic fields. Perturbed gas/liquid interfaces require hours to equilibrate. Certain RF and magnetic signals also produce reactive oxygen and hydrogen species (superoxide, hydrogen peroxide, hydrogen, atomic hydrogen). The perturbed gas/liquid interface modifies the hydrogen bonding networks in water and also the hydration of ions and interfaces. Careful outgassing removes all of the effects of the electromagnetic fields, including the magnetic memory effect. The amplitude of the applied field influences the observed effects. Different amplitudes of RF radiation perturb the interfacial water in different ways and consequently affect the behavior of colloids and ions in specific manners. For instance, the bulk and template precipitation of calcium carbonate, zeta potentials of suspended colloids, rate of dissolution of colloidal silica, and attachment of colloidal silica to metal surfaces are modified in specific ways with the low amplitude or high amplitude RF treatments described in this paper. The solubility/diffusivity of gas species is also modified in a different manner, and it is probably at the core of the specificity of the RF amplitude effects. 相似文献
12.
Juraj Bunta Martin Dahlberg Leif Eriksson Nikolai Korolev Aatto Laaksonen Raimo Lohikoski Alexander Lyubartsev Miroslav Pinak Patric Schyman 《International journal of quantum chemistry》2007,107(2):279-291
This work highlights four different topics in modeling of DNA: (i) the importance of water and ions together with the structure and function of DNA; the hydration structure around the ions appears to be the determining factor in the ion coordination to DNA, as demonstrated in the results of our MD simulations; (ii) how MD simulations can be used to simulate single molecule manipulation experiments as a complement to reveal the structural dynamics of the studied biomolecules; (iii) how damaged DNA can be studied in computer simulations; and (iv) how repair of damaged DNA can be studied theoretically. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 相似文献
13.
Zdenìk Vít Daniela Gulková Ludìk Kalua Miroslav Zdrail 《Reaction Kinetics and Catalysis Letters》2004,83(2):237-244
The effect of support (SiO2-Al2O3, Al2O3,MgO) of the Rh-Mo(S) sulfide catalysts on the synergy in hydrodesulfurization (HDS) of thiophene and hydrodenitrogenation
(HDN) of pyridine was studied. The synergy in HDS was between 7–10 regardless of the kind of support used. The synergy in
HDN varied from none over the MgO supported sample to about 3 over SiO2-Al2O3 supported catalyst, in accord with the positive effect of increasing support acidities.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
A method for the preparation of methyl 4-O-methyl-alpha-D-glucopyranuronate and its single crystal X-ray structure determination are reported. The molecule adopts an almost ideal (4)C1 ((degree)C3) conformation. 相似文献
15.
Preconcentration was effected using a 50 mm × 2 mm i.d. minicolumn packed with a spherical cellulose sorbent with chemically bound quinolin-8-ol function groups (Ostorb Oxin). The column was connected to the nebulizer of the atomic absorption spectrometer and the sample solution and eluent (2 M hydrochloric acid) were sucked through it at a flow-rate of 2–3 ml min?1 by utilizing the negative pressure of the nebulizer. The experimental design was tested with the determination of traces of copper. Peak-area and peak-height measurements were compared. Owing to the simple calibration, the former method was used for quantification. The dynamic range was from 0.3 ng ml?1 (detection limit) to 5 μg ml?1 (breakthrough). The reproducibility in the concentration range 25 ng ml?1-5 μg ml?1 was better than 5%. Water-soluble inorganic salts, ammonia and sodium hydroxide were analysed. The accuracy of the results was checked by anodic-stripping voltammetry and by electrothermal AAS. 相似文献
16.
An electrochemical method for the determination of the ionophores monensin and lasalocid was developed, based on the polarization of an agar gel/nitrobenzene electrolyte interface. The measured current corresponding to the facilitated ion transfer across this interface is directly proportional to the concentration of an ionophore dissolved in the organic phase. Using cyclic voltammetry in a three-electrode system the detection limit for both ionophores is about 3 × 10?5 M. 相似文献
17.
Miroslav Ploščica 《Algebra Universalis》1994,31(1):135-146
Presented by R. Freese. 相似文献
18.
Miroslav Bartušek 《Georgian Mathematical Journal》1996,3(4):301-314
Sufficient conditions are given for the existence of oscillatory proper solutions of a differential equation with quasiderivativesL
n
y=f(t,L
0
y, ..., L
n–1
y) under the validity of the sign conditionf(t,x
1
,...,x
n
)x
10,f(t,0,x
2
,...,x
n
)=0 on + x
n
. 相似文献
19.
20.