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1.
A number of aldimines of 7-aminopyrrolo[2,3-d]pyrimidine have been synthesized by the action of bromine on hydrazones of 5-allyl-4-hydrazinopyridine. The structures of the compounds obtained were confirmed by IR spectroscopy and mass spectrometry.For Communication 57, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 678–681, May, 1985.  相似文献   
2.
The possibility of obtaining dispersed powders of cobalt and zinc-nickel ferrites with particle size of 1-4 m by thermal treatment of the corresponding oxalates was analyzed. Changes in porous characteristics of the ferrites obtained in their thermal treatment were studied.  相似文献   
3.
Set-Valued and Variational Analysis - The fixed points and coincidence points of mappings of v-metric spaces, i.e., sets on which a vector metric is defined, are investigated. The values of such a...  相似文献   
4.
ESR studies have revealed that in the complex conjugated transformations of chalcopyrite under the effect of gasphase chain oxidation of methane and hydrogen, free radicals are formed. These radicals are sulfur-containing paramagnetic particles.
. , .
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5.
Some chromatographic properties of microspheric silica gels coated with copolymer of polystyrene, p-divinylbenzene, and allyl alcohol were studied. The measurements were performed by reverse-phase high-performance liquid chromatography using modified C8 and C1 8 phases with secondary silanization with trimethylchlorosilane.  相似文献   
6.
The intramolecular cyclization of dialkyl(2-butynyl-4-hydroxy)[3-(p-chlorophenyl)propargyl]ammonium chlorides, catalyzed by aqueous KOH, was realized. It was shown that the obtained products — 2,2-dialkyl-6-chloro-4-hydroxymethylbenzo[f]isoindolinium chlorides — readily undergo recyclization under the action of a twofold molar amount of KOH in aqueous solution with heating with the formation of 4-dialkylaminomethyl-8-chloro-1,3-dihydronaphtho[1,2-c]furans. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 834–840, June, 2007.  相似文献   
7.
For a givenρ(1/2 <ρ < + ∞) let us set L ρ = {z: |arg z| = π/(2ρ)} and assume that a real valued measurable function ?(t) such that ?(t) ≥ 1(t ∈ L ρ ) and \(\mathop {\lim }\limits_{|t| \to + \infty } \varphi (t) = + \infty (t \in L_\rho )\) is defined on L ρ . Let C ? (L ρ ) denote the space of continuous functionsf(t) on L ρ such that \(\lim \tfrac{{f(t)}}{{\varphi (t)}} = 0\) , where the norm of an elementf is defined as: \(\parallel f\parallel = \mathop {\sup }\limits_{t \in L_\rho } \tfrac{{|f(t)|}}{{\varphi (t)}}\) . In this note we pose the question about the completeness of the system of functions of the Mittag-Leffler type {Eρ(ut; μ)} (μ ≥ 1, 0 ≤ u ≤a) or, what is the same thing, of the system of functions \(p(t) = \int_0^a {E_\rho (ut;\mu )d\sigma (u)} \) in C ? (L ρ ). The following theorem is proved: The system of functions of the Mittag-Leffler type is complete in C ? (L ρ ) if and only if sup |p(z)| ≡ +∞, z ∈ L ρ , where the supremum is taken over the set of functions p(t) such that ∥p(t) (t + 1)?1 ∥ ≤ 1.  相似文献   
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9.
In this study, we investigate micelle fission of long-chain alkyl sulfonate molecules using atomistic scale simulation. GROMACS software code with the united atom force field was applied. 0.5-μs parallel molecular dynamics simulation study was conducted for a surfactant/water system consisting of 192 sodium pentadecyl sulfonate and 40,553 water molecules. The large preassembled micelle was ruptured at Krafft above T?=?323-K temperature, and we track two ellipsoid-like micelles over the course of the production run. To estimate the micelle shape, we determined the principal moments of inertia and the eccentricity, which proved that the micelles have a pronounced prolate spheroid shape, which agrees well with our previous experimental data. The mechanism of micelle fission was explored in detail. The aggregation number, ionization degree, and other parameters obtained from simulation were consistent with existing experimental finding. The determined parameters in addition to simple visual inspection of trajectories revealed monomer-micelle exchange—with the estimated relaxation time τ 1?=?10??9s. We assume that the exchange process is conditioned by the unequal size of micelles leading to adjustment of aggregation number.  相似文献   
10.
Propagation of four laser pulses in the five-level ladder system in the case of arbitrary intensities and the different strengths of oscillators is investigated, when one of the eigenstates of the interaction Hamiltonian is formed in the whole volume of the medium. Taking into account the first non-adiabatic correction, the equations of propagation are obtained. An analytical solution of these equations is obtained. The conditions for an effective excitation of the fifth level in the whole volume of medium and the limitations on the interaction parameters are obtained as well.  相似文献   
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