A high temperature dual-mode quartz crystal microbalance technique for erosion and thermal desorption spectroscopy measurements.

An improved quartz crystal microbalance measurement method is described, which allows us to determine erosion, implantation, and release rates of thin films, during changing temperatures and up to 700 K. A quasi-simultaneous excitation of two eigenmodes of the quartz resonator is able to compensate for frequency drifts due to temperature changes. The necessary electronics, the controlling behavior, and the dual-mode temperature compensation are described.

Experimental observation of a magnetic-turbulence threshold for runaway-electron generation in the TEXTOR tokamak.

Magnetic turbulence is observed at the beginning of the current quench in intended TEXTOR disruptions. Runaway electron (RE) suppression has been experimentally found at magnetic turbulence larger than a certain threshold. Below this threshold, the generated RE current is inversely proportional to the level of magnetic turbulence.

Neoclassical toroidal plasma viscosity torque in collisionless regimes in tokamaks.

Bumpiness in a magnetic field enhances the magnitude of the plasma viscosity and increases the rate of the plasma flow damping. A general solution of the neoclassical toroidal plasma viscosity (NTV) torque induced by nonaxisymmetric magnetic perturbation (NAMP) in the collisionless regimes in tokamaks is obtained in this Letter. The plasma angular momentum can be strongly changed, when there is a small deviation of the toroidal symmetry caused by a NAMP of the order of 0.

Multiresonance effect in type-I edge-localized mode control with low n fields on JET.

Multiple resonances in the edge-localized mode (ELM) frequency (f(ELM)) as a function of the edge safety factor q(95) have been observed for the first time with an applied low n (=1,2) field on the JET tokamak. Without an n=1 field applied, f(ELM) increases slightly from 20 to 30 Hz by varying the q(95) from 4 to 5 in a type-I ELMy H-mode plasma. However, with an n=1 field applied, a strong increase in f(ELM) by a factor of 4-5 has been observed with resonant q(95) values, while the f(ELM) increased only by a factor of 2 for nonresonant values.

Active control of type-I edge-localized modes with n=1 perturbation fields in the JET tokamak.

Type-I edge-localized modes (ELMs) have been mitigated at the JET tokamak using a static external n=1 perturbation field generated by four error field correction coils located far from the plasma. During the application of the n=1 field the ELM frequency increased by a factor of 4 and the amplitude of the D(alpha) signal decreased. The energy loss per ELM normalized to the total stored energy, DeltaW/W, dropped to values below 2%.

Forced magnetic reconnection and field penetration of an externally applied rotating helical magnetic field in the TEXTOR tokamak.

The magnetic field penetration process into a magnetized plasma is of basic interest both for plasma physics and astrophysics. In this context special measurements on the field penetration and field amplification are performed by a Hall probe on the dynamic ergodic divertor (DED) on the TEXTOR tokamak and the data are interpreted by a two-fluid plasma model. It is observed that the growth of the forced magnetic reconnection by the rotating DED field is accompanied by a change of the plasma fluid rotation.

Properties of geodesic acoustic modes and the relation to density fluctuations.

The geodesic acoustic mode (GAM) is a high frequency branch of zonal flows, which is observed in toroidal plasmas. Because of toroidal curvature effects, density fluctuations are excited, which are investigated with the O-mode correlation reflectometer at TEXTOR. This Letter reports on the poloidal distribution of GAM induced density fluctuation and compares them with theoretical predictions.

Influence of the dynamic ergodic divertor on the density limit in TEXTOR.

A significant influence of the dynamic ergodic divertor (DED) on the density limit in TEXTOR has been found. In Ohmic discharges, where without DED detachment normally arises at the density limit, a MARFE (multifaceted asymmetric radiation from the edge) develops when the DED is operated in a static regime. The threshold of the MARFE onset in the neutral beam heated plasmas is increased by applying 1 kHz ac DED at the high-field side.

Toroidal plasma rotation induced by the dynamic ergodic divertor in the TEXTOR tokamak.

The first results of the Dynamic Ergodic Divertor in TEXTOR, when operating in the m/n=3/1 mode configuration, are presented. The deeply penetrating external magnetic field perturbation of this configuration increases the toroidal plasma rotation. Staying below the excitation threshold for the m/n=2/1 tearing mode, this toroidal rotation is always in the direction of the plasma current, even if the toroidal projection of the rotating magnetic field perturbation is in the opposite direction.

Quasistationary high confinement discharges with trans-greenwald density on TEXTOR-94.

Confinement quality as good as ELM-free H-mode at densities substantially above the Greenwald density limit ( &nmacr;(e,0)/n(GW) = 1.4) has been obtained in discharges with a radiative boundary under quasistationary conditions for 20 times the energy confinement time. This is achieved by optimizing the gas-fueling rate of RI-mode discharges which tailors their favorable energy confinement and leads to discharges with beta values just below the operational limit beta(n) = 2 of TEXTOR-94, thereby effectively avoiding confinement back transitions or disruptions.

Enhanced Spontaneous Platelet Aggregation and red Blood Cell Fragility in Whole Blood Obtained from Patients with Diabetes.

SUMMARY. Using a platelet counting technique, spontaneous platelet aggregation (SPA) was determined in citrated whole blood (WB) and platelet-rich plasma (PRP) obtained from 27 patients with insulin-dependent diabetes mellitus and from 32 healthy controls. SPA in WB, but not in PRP, was significantly enhanced in the patients compared with the controls.

[The significance of HbA1 determination in children].

The determination of glycated haemoglobin permits a good evaluation of metabolic regulation of diabetics. The development of vascular complications depends on duration and degree of hyperglycemia. It is presented the different chemical reactions of glucose with proteins in diabetes.