Binuclear Copper(II) Complexes with Hydrazones Containing Spiropyran Fragment

New hydrazones were prepared by the reaction of new spiropyran of benzoxazine series and aliphatic acid hydrazides; their binuclear complexes were synthesized.     

Spontaneous hydration of the carbonyl group in substituted propynals in aqueous medium

Uncatalyzed hydration of the carbonyl group in substituted propynals in aqueous medium was studied by ¹H NMR spectroscopy in D₂O. The concentration of the resulting geminal diols in the equilibrium mixture was found to strongly depend on the substituent at the triple bond; it decreased in the R series Me₃Si > Me₂COH > Me₃C > Ph > Et₃Ge. Elevated temperature induced shift of the equilibrium toward the initial aldehyde. According to the 2D ROESY data, the geminal diol moiety in hydrated 3-trimethylsilylpropynal is effectively involved in the complex formation with β-cyclodextrin.     

Efficient generation of Xe K-shell x rays by high-contrast interaction with submicrometer clusters

The interaction between a 25 TW laser and Xe clusters at a peak intensity of 1 × 101? W/cm2 has been investigated. Xe K-shell x rays, whose energies are approximately 30 keV, were clearly observed with a hard x-ray CCD at 3.4 MPa. Moreover, we studied the yield of the Xe K-shell x rays by changing the pulse duration of the laser at a constant laser energy and found that the pulse duration of 40 fs is better than that of 300 fs for generating Xe K-shell x rays.     

Highly efficient relativistic-ion generation in the laser-piston regime

An intense laser-plasma interaction regime of the generation of high density ultrashort relativistic ion beams is suggested. When the radiation pressure is dominant, the laser energy is transformed efficiently into the energy of fast ions.     

Three-dimensional relativistic electromagnetic subcycle solitons

Three-dimensional (3D) relativistic electromagnetic subcycle solitons were observed in 3D particle-in-cell simulations of an intense short-laser-pulse propagation in an underdense plasma. Their structure resembles that of an oscillating electric dipole with a poloidal electric field and a toroidal magnetic field that oscillate in phase with the electron density with frequency below the Langmuir frequency. On the ion time scale, the soliton undergoes a Coulomb explosion of its core, resulting in ion acceleration, and then evolves into a slowly expanding quasineutral cavity.     

Photo- and thermochromic spiropyrans. 21. 8"-Formyl-3,6"-dimethyl-4-oxospiro(3,4-dihydro-2H-1,3-benzoxazine-2,2"-[2H ]chromene) possessing photochromic properties in the solid phase

Spiropyran of the chromene series, viz., 8"-formyl-3,6"-dimethyl-4-oxospiro(3,4-dihydro-2H-1,3-benzoxazine-2,2"-[2H]chromene), was synthesized. In the solid phase, this compound exhibits photochromic properties. These properties were examined and the crystal structure of the compound was established by X-ray diffraction analysis. The compound is a convenient starting reagent for the synthesis of new spiropyrans containing functional groups at position 8".     

Features of Nonstationary and Nonlinear Sound Scattering by Bubbles and Possibilities of Their Spectroscopy

Acoustical Physics - In this paper, we show the possibility of using nonstationary and nonlinear sound scattering for diagnosing bubbles in a liquid. Nonstationary sound scattering arises due to...     

Ionography of nanostructures with the use of a laser plasma of cluster targets

It has been shown that a femtosecond plasma of cluster targets is an almost isotropic source of fast ions and, hence, can be used to obtain ionographic images with a wide field of view. The spatial resolution of the resulting ionographic images is no worse than 600 nm, which corresponds to a uniquely high value of about 105 of the ratio of the field of view to the resolution. The use of 100–300-keV ion fluxes ensures the sensitivity of the method to the sample thickness of no worse than 100 nm even for samples consisting of light chemical elements (C, H). The proposed method can be used to obtain images of low-contrast biological objects, thin films, membranes, and other nanostructured objects.