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INTRODUCTION The wide use of state-of-the art mass-spectrometry methods with soft ionization, such as electrospray ionization (ESI), atmospheric pressure chemical ionization (ACPI), and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry, results [...], A novel derivatization method for the analysis of primary amines by MALDI mass spectrometry is proposed. Tris(2,6-dimethoxyphenyl) methyl carbenium cation reacts smoothly with primary amines, forming permanently charged adducts with the mass increment +359 Da and absorbance in the UV region. The approach was tested on a number of amines, including biologically active compounds and therapeutic agents. Keywords: trityl cation, derivatization, amines, MALDI mass spectrometry

Results of low-temperature (LT) characterizations of local rf properties of passive superconducting (SC) microwave devices are reported. A new Laser Scanning Microscope (LSM) is used.

This article analyzes the Russian budgetary system, focusing on its systematic shortcomings which are largely derived from the imbalance between spending obligations and the revenue base, suggesting the need to eliminate this gap through structural reforms in the economic policy; a reduction in expenditures is recommended, and requires refrom in social, defense and state administration, as well as tax reforms. Issues addressed include the structure of the budget sector in Russia, analysis of the budget sphere, estimations of the magnitude of obligations in the budget sector, principle problems of the Russian budget system, and the effects of structural reforms on the budget.

Issues concerning the measurement of local transport properties of superconducting filaments, extracted from (Bi,Pb)2Sr2Ca2Cu3O10/Ag tapes, using low temperature scanning laser microscopy, are discussed.

Scanning laser microscopy was used for imaging sub-millimeter waves in planar cryelectronic circuits.

Research is presented concerning the high frequency measurements of Josephson junction arrays which are underdamped, in the form of parallel biased cells in two rows. The geometries of the junctions are discussed.

A study used electron beam lithography to fabricate the properties of high-quality, ultra-narrow long Josephson junctions with gradually decreasing width down to less than 0.3 microns. Analysis of these Josephson transmission lines indicated a strong dependence of the junction characteristic parameters on the junction width. The data are described in a consistent manner by considering a general-type width dependence of the phase gradient on the magnetic field.

A double-junction stacked Josephson flux-flow oscillator on-chip coupled to a superconductor-insulator-superconductor detector was subjected to radiation measurements. A broad band coupling circuit was employed for impedance matching between the detector and the oscillator. The detector exhibited radiation power of up to 10 nW in the 170 and 410 GHz frequency range. Two stacked junctions emitted coherent radiation at the fundamental Josephson frequency and at its second harmonic.

A study was conducted on the magnetic field dependence of 7-layer stacked Nb/AlAlOx/Nb long Josephson junctions' current voltage characteristics. The common superconducting electrodes with thicknesses less than the London penetration depth provide the magnetic coupling in the junctions. A complex structure of cavity-like resonances modulate the flux-flow characteristics. Pronounced resonant modes with large voltage spacing were observed in the intermediate magnetic field range.

Parallel one-dimensional arrays composed of double-layer stacked small Josephson tunnel junctions were experimentally and numerically investigated. In addition to various features already known for classic single-layer arrays, a new resonant state which corresponds to the locking of the fluxon oscillations to a frequency of small-amplitude oscillations of the superconducting phase in middle islands of small stacks was discovered. Numerical simulations of a simplified circuit were in agreement with experiments and confirmed the proposed qualitative mechanism. There was no proof for the so-called multiple-fluxon propagation in double-junction arrays.

The radiation emission by a system of two magnetically coupled, long Josephson junctions is numerically examined. Simulations indicate that Josephson junctions operating in the in-phase flux-flow mode may generate radio frequency radiation power by a factor of more than four larger than that of a single Josephson junction. The radiation in the out-of-phase flux-flow mode is characterized by almost completely suppressed amplitudes of odd harmonics and considerably damped even harmonics in contrast to that of a single barrier junction.

Fluxon resonances known as zero-field steps in current-voltage characteristics of long Nb/A1-A1Ox/Nb Josephson junctions made in a window of a stripline is measured with battery-powered current sources for the bias current and magnetic field. Results indicate the appearance of fine structure resonances in fluxon resonant steps and an increase in the effective fluxon propagation velocity. The findings are in agreement with previous measurements.

Double-barrier, long-stacked Josephson tunnel junctions of overlap geometry and with external electric contract to their middle electrodes are developed with the use of Nb-A1/A1Ox-Nb technology. Thicknesses of 90 nm were achieved with the use of a planarization technique. Equal voltage across the top and bottom junctions, which are both of high quality, were observed by biasing the junctions.

The flux-flow dynamic behavior of vertically stacked long Josephson tunneling junctions fabricated via an in situ process is studied by current-voltage and magnetic measurements. The measured data shows the presence of two different mutually phase-locked regimes in the junctions, the lower-velocity anti-phase mode and the high velocity in-phase mode. These modes can be tuned by the magnetic field in a broad voltage range.

Low temperature scanning electron microscopic studies of the higher order zero field steps of long inline and overlap Josephson junctions suggest the possible occurrence of several stable states in the presence of more than one fluxon in the junction. The occurrence is associated with different spacing among fluxons during their propagation. The emitted radiation spectrum is associated with the variation in these dynamic states. Numerical simulations attribute fluxon interaction with plasma oscillations to the observed behavior.

Numerical investigation of the magnetic fluxon dynamics in a system with two vertically stacked long Josephson junctions reveals that the junctions exhibit a stable phase-locked flux-flow resonance. The numerical investigation is based on a method proposed by S. Sakai, P. Bodin and N.F. Pedersen and uses strongly coupled sine-Gordon equations. These systems can be used for oscillators in the millimeter and sub-millimeter band.

Low temperature scanning electron microscopic technique is employed for the spatially resolved investigation of single-electron tunneling (SET) circuits. Signals from various parts of the circuits are imaged with the help of circuit voltage, recording as a function of the beam coordinates. Charge trapping near SET-transistor induces memory effect. The efficiency of this technique is demonstrated with a system having 11 electrons.

Russia's decision to join the Missile Technology Control Regime (MTCR) and abort the sale of cryogenic rockets to India will serve its national interests and strengthen its international position, though many feel that Russia has deprived itself of an opportunity to compete in the technology market. Russia's joining the MTCR will help limit the proliferation of missile technology and increase its cooperation with developed countries in space programs. Russia's cancelling the sale of cryogenic rockets will not affect its relations with India as the trade of rocket engines for peace purposes will continue.

The interaction of fluxons with Abrikosov vortices in long quasi-one-dimensional Josephson junctions was investigated. An electron beam technique was used to inject an Abrikosov vortex into a long Josephson junction. The interaction force between the vortex and the fluxons in the junction was then measured using the critical current values. Results show that the trapped magnetic flux quanta induced by the vortex-fluxon interaction has a strong influence on the performance of the Josephson junction.

The movement of fluxon between the superconducting electrodes of a Josephson junction was studied. Long linear Josephson junctions were subjected to a relatively high magnetic field. The current-voltage curves were then obtained by a sequential crossing of the junctions with an applied electron beam generated by a flux-flow oscillator. Results indicate that the movement of fluxon in the junction induces large narrow band radiation in the frequency range of 62 to 77 gigahertz.

The synchronous interaction between coupled superconducting quantum interference devices (SQUID) is studied. Numerical simulations and experimental investigations are performed to determine the parameters affecting the interaction mechanism and analyze the flux dynamics inthe SQUID circuit. Results indicate that the coupling intensity between the SQUIDs is strongly dependent on the thickness of the semiconducting layers.

We report on the fabrication of highly transparent superconductor/normal metal/two-dimensional electron gas junctions formed by a superconducting NbN electrode, a thin (10 nm) Au interlayer, and a two-dimensional electron gas in an InGaAs/InP heterostructure. High junction transparency has been achieved by exploiting developed process of Au/NbN evaporation and rapid annealing at 400 °C. This allowed us to observe a decrease in the differential resistance with pronounced double-dip structure within the superconducting energy gap in superconductor/two-dimensional electron gas (2DEG) proximity systems. The effect of a magnetic field perpendicular to the plane of the 2DEG on the differential resistance of the interface was studied. It has been found that the reduced subgap resistance remains in high magnetic fields. Zero-field data are analyzed within the previously established quasiclassical model for the proximity effect. [ABSTRACT FROM AUTHOR]

Different imaging modes of low temperature laser scanning microscopy (LTLSM) are used for probing local optical and superconducting properties, as well as the spatial variations in thermoelectric and electronic transport in a Y[Ba.sub.2][Cu.sub.3][O.sub.6.95]/LaAl[O.sub.3] (YBCO/LAO) superconducting microstrip resonator with micron-range resolution. The results have shown the direct spatial correlation between nonlinearity (NL) microwave and dc electronic transport properties of the YBCO film that are imposed by the twin-domain topology of the LAO substrate.

Phase-locking of unidirectional flux-flow motion in long quasi-one-dimensional Josephson junctions was investigated. The results showed that when the external source was connected to the boundary which synchronizes the fluxons entering the junction, large radio frequency-induced steps were observed. The external source functioned like a gate at the boundary. In addition, the phase-locked step amplitude exhibited a resonance-dependence on the external magnetic field.

Low-temperature laser scanning microscopy (LSM) technique applied to image guided motion of vortices in patterned high-[T.sub.c] films revealed guidance of vortices by artificial microholes. It is proved that vortices are steered between antidots into a priori chosen direction by imaging of resistive photoresponse with a spatial resolution down to about 1 mum.

The operation of a toggle flip top with zero-geometrical inductance of the fluxon storage loop is simulated. The simulations show that the parametric inductance of the Pi-junction and its normal resistance R(Sub n) form a low-pass filter, which sets the low limit for Pi-junctions I(Sub c)(Super pi)R(Sub n) product, but offers a wide range of variations of the other parameters.

We have found that the size of some rapid single-flux quantum (RSFQ) logic cells based on conventional 0-type Josephson junctions can be significantly reduced by using a π-type junction as a phase shifter in passive (nonswitching) mode. In comparison with the recently suggested active (switching) π-junctions mode, the passive mode offers much greater operation margins for their critical current I[sub c][sup π]. This gives π-junctions a chance to be implemented in RSFQ designs in the near future. As an example, we have simulated the operation of a toggle flip flop with zero-geometrical inductance of the fluxon storage loop. Simulations show that the parametric inductance of the π-junction and its normal resistance R[sub n] form a low-pass filter, which sets the low limit for π-junctions I[sub c][sup π]R[sub n] product, but offers a wide range of variations of the other parameters. The possible reduction of RSFQ cell size by using π-junctions opens the way to scale superconducting logic circuits down to the submicron dimensions. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]