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941.
Yu. V. Kaletina V. M. Schastlivtsev E. A. Fokina 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(12):1667-1673
The effect of magnetic treatment on the isothermal martensitic transformation in the Fe-24% Ni-4% Mn alloy has been investigated. The martensitic transformation in a dc magnetic field at liquid-helium temperature has been analyzed. 相似文献
942.
A. Ya. Braginskii 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(2):181-186
For the case of a phase transition into a macroscopically inhomogeneous state described by the order parameter (OP) that is characterized by a multiarm star of a vector {ki}, a method for compensating the spatial variation in all star arms ki is proposed. To this end, a unified tensor field (OP connectivity) is considered, which is interpreted as a stress field potential. The OP-connectivity interaction is described by the phenomenological dislocation charge. Alternative ways of physical interpretation of the OP connectivity are discussed. 相似文献
943.
V. I. Zubkov I. S. Shulgunova A. V. Solomonov M. Geller A. Marent D. Bimberg A. E. Zhukov E. S. Semenova V. M. Ustinov 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(1):106-108
In this work, charge-carrier capture by an array of self-assembled InAs/GaAs quantum dots was directly observed for the first time by capacitance recharge. It is proposed to process the obtained transient-capture data by a similar method to that used for emission, by the box-car method. The capture activation energies are determined and compared with the emission activation energies. 相似文献
944.
Distortions induced by an external magnetic field in the magnetic structure of a thin layer of a uniaxial collinear antiferromagnet
with rough surfaces are studied using computer simulation. It is shown that, under certain conditions, the presence of atomic
steps at the layer surfaces causes the antiferromagnetic layer to break up into domains. The character and magnitude of distortions
are found for an arbitrary ratio of the distance between atomic steps to the order parameter correlation length.
Original Russian Text ? A.I. Morosov, I.A. Morosov, A.S. Sigov, 2007, published in Fizika Tverdogo Tela, 2007, Vol. 49, No.
7, pp. 1228–1235. 相似文献
945.
L. A. Bityutskaya V. V. Distler V. V. Kryachko M. A. Yudovskaya M. V. Grechkina E. V. Bogatikov 《Physics of the Solid State》2007,49(7):1382-1386
Nanostructuring of natural isoferroplatinum crystals is revealed by atomic-force microscopy for the first time. Typical scales of ~30, 50, and 100 nm are determined and the self-affine character of their relation is established using a wavelet analysis. 相似文献
946.
Ph. Komninou Th. Kehagias A. Delimitis G.P. Dimitrakopulos J. Kioseoglou E. Dimakis A. Georgakilas Th. Karakostas 《Superlattices and Microstructures》2004,36(4-6):509
The structural properties of InN thin films, grown by rf plasma-assisted molecular beam epitaxy on Ga-face GaN/Al2O3(0001) substrates, were investigated by means of conventional and high resolution electron microscopy. Our observations showed that a uniform InN film of total thickness up to 1 μm could be readily grown on GaN without any indication of columnar growth. A clear epitaxial orientation relationship of , was determined. The quality of the InN film was rather good, having threading dislocations as the dominant structural defect with a density in the range of 109–1010 cm−2. The crystal lattice parameters of wurtzite InN were estimated by electron diffraction analysis to be a=0.354 nm and c=0.569 nm, using Al2O3 as the reference crystal. Heteroepitaxial growth of InN on GaN was accomplished by the introduction of a network of three regularly spaced misfit dislocation arrays at the atomically flat interface plane. The experimentally measured distance of misfit dislocations was 2.72 nm. This is in good agreement with the theoretical value derived from the in-plane lattice mismatch of InN and GaN, which indicated that nearly full relaxation of the interfacial strain between the two crystal lattices was achieved. 相似文献
947.
C. von Borczyskowski F. Cichos J. Martin J. Schuster A. Issac J. Brabandt 《The European physical journal. Special topics》2007,144(1):13-25
Optical spectroscopy in combination with wide field or confocal optical
microscopy enables the investigation of single quantum objects such as
organic molecules, II/VI semiconductor quantum dots and silicon nanocrystals.
They all have fluctuations of luminescence intensities on time scales longer
than μs in common. A comparison reveals that despite the large differences
of the nature of the respective quantum objects, the intensity fluctuations
are related to a slow ionisation process followed
by a trapping of the photoejected charge in the non-conducing environment.
Detailed aspects of the dynamics are controlled by the dielectric properties
of the matrix. 相似文献
948.
Explosion-produced plasma jets formed in free spece are experimentally investigated. The feasibility of emitting pulsed electromagnetic signals by plasma jets is shown, and the emitting conditions are studied. Comparison is made between the results of experiments with short and long plasma jets. When the jet passes through the field of a helix, a short-term increase in the emitted signal is detected. A linear parametric model of interaction between the plasma jet and an exciting electromagnetic signal is proposed. The operating performance of instrumentation developed for the investigation is presented. 相似文献
949.
A. M. Hashimov Sh. M. Hasanli R. N. Mehdizadeh Sh. M. Azizova Kh. B. Bayramov 《Technical Physics》2007,52(8):1086-1088
The resistivity of composite nonlinear resistors (varistors) consisting of zinc oxide ceramic and high-density polyethylene, as well as IR spectra and X-ray diffraction patterns taken of the samples, are studied. The component composition of the resistor is shown to influence its resistivity and IR and X-ray spectra. 相似文献
950.
Alpeshkumar K. Malde Santosh A. Khedkar Evans C. Coutinho 《Journal of Physical Organic Chemistry》2007,20(2):151-160
Modification of peptides to produce peptidomimetics is of great interest, with the aim of designing potent, selective, and metabolically stable analogs having certain conformational properties. Organoboranes have been reported in the literature with a wide range of therapeutic applications. One of the therapeutically important class of molecules is amine‐carboxyboranes derived from amino acids by replacement of the Cα atom of an amino acid/peptide by boron. The conformational preferences of these peptides, with respect to backbone ω, ?, and ψ torsion angles, have been investigated by theoretical calculations. The amide bond in these molecules has the same geometry in the ground and transition states as the natural peptides. However, the boron isosteres of glycine and alanine peptides are less structured than their natural derivatives, but are distinguished by structures with a positive value for the ? angle, which is normally disfavored for natural peptides. This property could be used to build peptides with a geometry not usually seen in natural peptides. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献