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991.
We review the main features of odd triplet superconductivity in superconductor-ferromagnet (S/F) structures. We discuss the different types of superconducting condensate that can be experimentally observed and pay special attention to the triplet component induced in a ferromagnet which is in contact with a superconductor. The triplet component is an even function of the momentum and an odd function of the frequency and leads to novel phenomena. PACS 74.78.Fk; 73.23.-b; 74.50.+r; 75.70.-i  相似文献   
992.
Various classes of non-associative algebras possessing the property of being rigid under abstract isomorphisms are studied. Supported by RFBR grant No. 06-01-00159a. __________ Translated from Algebra i Logika, Vol. 46, No. 4, pp. 483–502, July–August, 2007.  相似文献   
993.
994.
995.
Molecular devices have lately attracted increased attention due to some appealing features such as their low production cost, flexibility in the substrate choice, possibility of large area deployment, and possibly higher integration capabilities. Starting from a series of results obtained from our groups, we critically review the state-of-the-art in the field of simulation of organic and molecular systems, by analyzing and comparing existing approaches, and looking at the open problems and possible solutions and future developments. PACS 72.80.Le  相似文献   
996.
The equilibria between tungsten(VI) and iminodiacetic acid (IDA) have been studied in aqueous solution. The stoichiometry and stability constants of the complexes formed are determined from a combination of potentiometric and Uv spectroscopic measurements. All measurements are carried out at 25°C, pH 7.5 and different ionic strengths ranging from (0.1 to 1.0) mol dm−3 (NaClO4). According to these results, tungsten(VI) forms a mononuclear complex with IDA of the type (WO3L2−). By introducing two empirical parameters C and D in the complex-formation reaction between tungsten(VI) and IDA, the dependence of the dissociation and stability constants on ionic strength is described by a modified Debye-Huckel-type equation. Finally, a pattern for the ionic strength dependence is obtained.  相似文献   
997.
According to a classical result due to Hudson, the Wigner function of a pure, continuous-variable quantum state is non-negative if and only if the state is Gaussian. We have proven an analogous statement for finite-dimensional quantum systems. In this context, the role of Gaussian states is taken on by stabilizer states. The general results have been published in [1]. For the case of systems of odd prime dimension, a different, greatly simplified method of proof can be employed which still exhibits the main ideas. The present paper gives a self-contained account of these methods. PACS  03.65.Fd; 03.65.Sq; 03.67.-a  相似文献   
998.
Photosensitive glass is a potentially important material for micro-fluidic devices that can be integrated with micro-optical components for biochemical analysis. Here, we demonstrate the fabrication of optical waveguides inside glass by femtosecond laser direct writing. The influence of the laser parameters on the waveguide properties is investigated, and it is revealed that the waveguide mode can be well controlled. The single mode is achieved at a low writing energy, while the multimode is achieved with increasing energy. In spite of a longitudinally elongated elliptical shape of the cross-sectional profile, the far-field pattern of the single-mode waveguide shows an almost symmetric profile. The measured propagation loss and the coupling loss are evaluated to be ∼0.6 dB/cm and ∼1.6 dB at a wavelength of 632.8 nm, respectively, under the conditions of 1.0–2.0 μJ pulse energy and 200–500 μm/s scan speed. The increased optical loss is associated with a higher waveguide mode at higher writing energy. Furthermore, the integration of waveguides and a micromirror made of a hollow microplate inside the glass is demonstrated to bend the laser beam at an angle of 90° in a small chip. The bending loss is estimated to be smaller than 0.3 dB. PACS 42.62.-b; 42.82.Cr; 82.50.Pt; 42.79.Gn; 42.81.Qb  相似文献   
999.
A complex numerical and experimental investigation of burner devices for a reburning of the anode gas of aluminum production was carried out. The chosen mathematical model of the processes of aerodynamics, heat exchange, and gas burning was identified and adapted on the basis of data of real-scale measurements. Basing on computational experiments the optimization of the design of elements of the system for anode gas detoxication and transport was carried out. A new system was proposed and tested for reburning the anode gases of electrolysis production, which consists of an improved burner device and a dust-sedimenting chamber with a possibility of regulating the amount of gas suction.  相似文献   
1000.
An optical parametric oscillator using a periodically poled LiNbO3 crystal and a volume Bragg grating output coupler is presented. Signal and idler wavelengths of 2008 and 2264 nm were generated from the 1064 nm Nd:YVO4 pump laser. The Bragg grating was reflecting in a narrow band around 2008 nm, creating a purely singly resonant cavity. Signal and idler linewidths of approximately 0.44 and 0.72 nm, respectively, were measured. This is a reduction of 80 and 60 times compared to when using a mirror as output coupler. A total output energy of 156 μJ was measured with 47% slope efficiency. PACS 42.65.Yj; 42.72.Ai; 42.40.Eq  相似文献   
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