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91.
Interaction of a frequency-chirped laser pulse with single protons and a hydrogen gas target is studied analytically and by means of particle-in-cell simulations, respectively. The feasibility of generating ultraintense (10(7) particles per bunch) and phase-space collimated beams of protons (energy spread of about 1%) is demonstrated. Phase synchronization of the protons and the laser field, guaranteed by the appropriate chirping of the laser pulse, allows the particles to gain sufficient kinetic energy (around 250 MeV) required for such applications as hadron cancer therapy, from state-of-the-art laser systems of intensities of the order of 10(21) W/cm(2). 相似文献
92.
Luk’yanenko N. G. Kirichenko T. I. Lyapunov A. Yu. Kulygina E. Yu. Mazepa A. V. 《Russian Journal of Organic Chemistry》2009,45(2):304-311
New crownophane family was synthesized containing fragments of 2,7-dioxyfluorenone and hydroquinone connected with residues of tri- and tetraethylene glycols. The formation of inclusion complexes of these ligands with paraquat was established by means of mass spectrometry (fast-atom bombardment), 1H NMR and electronic spectroscopy. The crownophane with a larger ring formed the more stable complex.
相似文献93.
A criterion for semiprime rings with finite decomposition of identity to be prime is given. We also present a brief survey
of some finiteness conditions related to the decomposition of identity. We consider the notion of a net of a ring and show
that the lattice of all two-sided ideals of a right semidistributive semiperfect ring is distributive. An application of decompositions
of identity to groups of units is given. 相似文献
94.
The fractal characteristics of a set of the effective field values are calculated for the Ising model with a random local
magnetic field on the Bethe lattice. The dependence of these characteristics on the random field value is investigated.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 14–18, December, 2005. 相似文献
95.
Dmitrii V. Zagorevskii Tatyana V. Volkova Sergey O. Yakushin Boris G. Antipov Yurii S. Nekrasov 《Journal of mass spectrometry : JMS》1991,26(9):748-750
Fragmentation of the acetyl- and propionyl-ferrocenes under electron impact together with the rupture of C? CO bonds, characteristic of ketones, also includes elimination of water and migration of the OH group to the central metal atom, which is due to keto-enol tautomerization of the acyl group in molecular or fragment ions. 相似文献
96.
S. P. Timoshenko Institute of Mechanics, National Academy of Sciences of the Ukraine, Kiev. Translated from Prikladnaya Mekhanika, No. 8, pp. 48–53, August, 1995. 相似文献
97.
We present experimental estimates of the possibility to use an adapted ground penetrating radar (GPR) for mapping subsurface zones (lenses) polluted by oil products as a result of ecological accidents. The radar was tested at the site of a large lens with air kerosene at a depth of about 6 m. On the basis of comparison of radar measurements and geological data obtained by well-boring it is shown that use of GPRs for mapping subsurface lenses with oil products is expedient. 相似文献
98.
99.
Mikhail E. Minyaev Dmitrii M. Roitershtein Ilya E. Nifant'ev Ivan V. Ananyev Tatyana V. Minyaeva Timofey A. Mikhaylyev 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(6):491-498
(1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐1,3,5‐triphenylcyclohexan‐1‐ol or (4‐hydroxy‐2,4,6‐triphenylcyclohexane‐1,3‐diyl)bis(phenylmethanone), C38H32O3, (1), is formed as a by‐product in the NaOH‐catalyzed synthesis of 1,3,5‐triphenylpentane‐1,5‐dione from acetophenone and benzaldehyde. Single crystals of the chloroform hemisolvate, C38H32O3·0.5CHCl3, were grown from chloroform. The structure has triclinic (P) symmetry. One diastereomer [as a pair of (1RS,2SR,3RS,4SR,5RS)‐enantiomers] of (1) has been found in the crystal structure and confirmed by NMR studies. The dichoromethane hemisolvate has been reported previously [Zhang et al. (2007). Acta Cryst. E 63 , o4652]. (1RS,2SR,3RS,4SR,5RS)‐2,4‐Dibenzoyl‐3,5‐bis(2‐methoxyphenyl)‐1‐phenylcyclohexan‐1‐ol or [4‐hydroxy‐2,6‐bis(2‐methoxyphenyl)‐4‐phenylcyclohexane‐1,3‐diyl]bis(phenylmethanone), C40H36O5, (2), is also formed as a by‐product, under the same conditions, from acetophenone and 2‐methoxybenzaldehyde. Crystals of (2) have been grown from chloroform. The structure has orthorhombic (Pca21) symmetry. A diastereomer of (2) possesses the same configuration as (1). In both structures, the cyclohexane ring adopts a chair conformation with all bulky groups (benzoyl, phenyl and 2‐methoxyphenyl) in equatorial positions. The molecules of (1) and (2) both display one intramolecular O—H...O hydrogen bond. 相似文献
100.