Synthesis of 4-(3-methylpyrazolyl-1)naphthalic anhydride

Heating 4-nitronaphthalic anhydride in an excess of 3(5)-methylpyrazole gives only 4-(3-methylpyrazolyl-1)naphthalic anhydride, which is converted by butylamine into the known N-butylimide of 4-(3-methylpyrazolyl-1)naphthalic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, p. 194, February, 1992.     

Synthesis of 2-benzamidothiazolines

2-Benzamido-5-methylene-2-thiazolines were obtained by reaction of -ethynylamines with benzoyl isothiocyanate. The resulting acylaminothiazolines have imino structures, while their hydrochlorides have amino structures.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 199–201, February, 1974.     

Quantum-Chemical Calculations of the Affinity of Neutral Molecules for Protons

Quantum-chemical calculations (B3LYP/6-31++G(d,p)) of proton affinities were performed for molecules of various structures in the gas phase. The errors in calculation results were estimated. The data on the proton affinity of several molecules for which experimental proton affinity values are unavailable were obtained. The hypothesis according to which the structure of heteroassociates in the HF-aprotic organic solvent systems depended on the proton affinity of solvent molecules was substantiated.     

A method of evaluating the strength and deformation characteristics of vacuum-hardened shells

Conclusions 1. The proposed experimental method makes it feasible to perform a sufficiently accurate comparative analysis of products obtained by different technological processes.2. The test results pertaining to strength and deformation characteristics of complete glass-plastic shells are in a sufficiently close agreement with data obtained in testing cut specimens.3. Application of this method to an evaluation of the characteristics of vacuum hardened glass-plastics made of various component materials has demonstrated the advantages of this particular technological process.Voroshilovgrad Institute of Machine Design. Translated from Mekhanika Polimerov, No. 1, pp. 138–142, January–February, 1977.     

Current-driven excitations in symmetric magnetic nanopillars

We study experimentally the current-driven magnetic excitations in symmetric Co/Cu/Co nanopillars. In contrast with all the previous observations where the current of only one polarity is capable of exciting a multilayer system saturated by an externally applied magnetic field, we observe that both polarities of the applied current trigger excitations in a symmetric multilayer. This may indicate that in symmetric structures the current propels high-frequency magnetic oscillations in all magnetic layers. We argue, however, that only one layer is excited in our multilayers but, interestingly, currents of opposite polarities excite different layers. This hypothesis is supported by modeling the spin accumulation in symmetric magnetic multilayers.     

Synthesis of MnP nanocrystals by treatment of metal carbonyl complexes with phosphines: a new, versatile route to nanoscale transition metal phosphides

The reaction of Mn2(CO)10 with P(SiMe3)3 in coordinating solvents at T >/= 220 degrees C yields low polydispersity, highly crystalline MnP nanoparticles for the first time. The effect of dimensional limiting has resulted in the stabilization of a ferromagnetic ground state at low temperatures, rather than the metamagnetic state observed in bulk (microcrystalline) MnP. The synthetic methodology reported here is demonstrated to be general for a number of different metals and phosphine sources.     

Dynamics of fluxons in Josephson junctions under the noise current action

The motion of magnetic flux quanta (fluxons) in long Josephson junctions (LJJ) under action of direct and random currents is under investigation. The velocity distribution function of fuxons is calculated which, even in the absence of the direct current component, is non-Gaussian. As a consequence, the current-voltage characteristic of a noise junction differs from that for a regular one. The dependence of the voltage difference on the current for junctions, both with and without the noisy current component, is shown to be non-monotonic. There is a good agreement between the calculation data and the numerical simulation results.     

Radiation of a cylinder in a viscous medium

The theory of radiation and propagation of sound waves in an ideal medium from a cylindrical surface has been presented in detail in [1–4]. The theory of radiation of a cylinder in a viscous medium is considered in the present paper.     

Triplets in extended nematic liquid crystals and polarons in their blends

Photoinduced absorption shows that triplets are the primary photoexcited species in a series of conjugated liquid crystals containing thiophene and fluorene groups. We find that the triplet generation rate can be varied substantially by molecular design. The introduction of extra thiophene groups into the elongated molecules changes the intersystem crossing rate by over two orders of magnitude, while modifying the singlet and triplet energies by only small amounts. This result is attributed to the high spin-orbit coupling constant of sulfur: An increase in the number of sulfur atoms increases the spin-orbit coupling between the singlet and triplet states. These results are relevant to the design of organic light emitting diodes, lasers, and other devices where triplet formation has a major impact on device performance. The molecules are shown to act as effective electron donors when blended with a perylene molecule which acts as an electron acceptor. The electron transfer rate is faster than the singlet lifetime so that the blend shows the efficient charge separation required for a photovoltaic device.