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The novel bimetallic Fe(II)Ag(I) thermal-induced spin crossover coordination polymer {Fe(II)(3,5-dimethylpyridine)(2)[Ag(I)(2)(CN)(3)][Ag(I)(CN)(2)]}(n) was synthesized by one-pot reactions between 3,5-dimethylpyridine and K[Ag(I)(CN)(2)] in the presence of Fe(II) salt (FeSO(4).(NH(4))(2)SO(4).6H(2)O). Magnetic studies demonstrate the occurrence of a spin transition. The crystal structure has been studied at 293 K and 80 K. The compound is made up of unprecedented three-dimensional networks topology of Fe(II) ions bridged by binuclear [Ag(I)(2)(CN)(3)](-) and mononuclear [Ag(I)(CN)(2)](-) units; [Ag(I)(2)(CN)(3)](-) anion is very rare. In this complex, the presence of the Ag(I) ions plays a significant role in increasing the dimensionality and cooperatively due to the triangular argentophilic interactions.

Ferrimagnetic materials can be expected to be useful as thermo seeds for hyperthermic treatment of cancer, especially where the cancer is located in deep parts of body, as they can generate heat by magnetic hysteretic loss when they are placed in an alternating magnetic field. Recently, it was reported that ferrimagnetic maghemite (gamma-Fe2O3) microspheres 20-30 microm in diameter prepared in aqueous solution can show excellent heat generating ability. However, these microspheres have many cracks on their surfaces. In this study, the preparation conditions for the microspheres was further optimized in order to obtain crack-free ferrimagnetic microspheres, and the in vitro heat generation of the obtained microspheres was measured in an agar phantom under an alternating magnetic field. Crack-free gamma-Fe2O3 microspheres 20-30 microm in diameter were obtained successfully. Their saturation magnetization and coercive force were 68 emu g(-1) and 198 Oe, respectively. Their heat generation under an alternating magnetic field of 300 Oe at 100 kHz was estimated to be 42 W g(-1). The microspheres showed in vitro heat generation when they were dispersed in an agar phantom and placed under an alternating magnetic field. It is believed that these microspheres may be useful for the in situ hyperthermic treatment of cancer.

Ferrimagnetic materials can be expected to be useful as thermal seeds for hyperthermic treatment of cancer, especially where the cancer is located in deep parts of body, as they can generate heat by magnetic hysteretic loss when they are placed in an alternating magnetic field. In this study, hollow magnetite (Fe(3)O(4)) particles were prepared using an enzymatic reaction of urease. A hollow particle was obtained by using a Pasteur pipette. The particle was 500 microm in size and was composed of Fe(3)O(4). Its saturation magnetization and coercive force were 57 emuxg(-1) and 183 Oe, respectively. Its heat generation under an alternating magnetic field of 300 Oe at 100 kHz was estimated to be 45 Wxg(-1). Microspheres 30 microm in diameter were also successfully obtained by using a spray gun.

We have developed a novel magnetic particle agglutination (MPA) method for rapid detection of antibody to human T-lymphotropic virus type I (HTLV-I). This method is suitable for screening determination. The assay uses purified viral antigen coated on magnetic particles, which are novel artificial particles made of gelatin, arabic gum, and ferrite. MPA uses a special magnet and inclined plate holder. In MPA, the specimen is incubated with magnetic particles in the well; magnetic particles are then magnetically attracted to the bottom of the well. Then the plate is inclined and read by the naked eye. In a positive specimen, agglutination particles stay at the bottom of the well. On the other hand, non-agglutination particles with negative sample run down the side of the well. The total assay time of MPA was estimated at 8 min/microtiter-plate. The results obtained by correlating MPA for the detection of HTLV-I antibody with other method emphasized the precision of MPA.

Describes an experiment where high density plasma was obtained without degradation of the diamagnetic signal with the application of electron cyclotron resonance heating. Density plasma production and confinement; Dependencies of the confining potential and confinement time on the plasma density; Determination of the scaling relations for the dependencies.

A formation mechanism of the plug potential in a tandem mirror is proposed. The orbits for ions, which are accelerated by the thermal barrier potential, are calculated numerically in a magnetic mirror field. A non-Maxwellian electron distribution function, which leads to a modified Boltzmann law, is assumed in order to determine the electrostatic potential profile. Monte Carlo simulation is carried out for ion dynamics to include the effects of Coulomb collisions and ion radial losses. It is found that the plug potential is formed under the condition that the ions trapped in the thermal barrier region are few. [ABSTRACT FROM AUTHOR]

The improvement of potential confinement was attained in the GAMMA 10 tandem mirror [Phys. Rev. Lett. 55, 939 (1985); Proceedings of the 13th International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Washington, 1990 (Intemational Atomic Energy Agency, Vienna, 1991), Vol. 2, p. 539] by axisymmetrization of heating systems for the plasma production, heating, and potential formation. A significant increase of the density and diamagnetism by the potential confinement was observed. In the previous experiment, it was difficult to increase the central cell density higher than 2.7 × 10[sup 18]m[sup -3] One of the possible mechanisms is the density clamping due to the eigenmode formation ofthe ion-cyclotron-range of frequency (ICRF) waves in the axial direction. With high harmonic ICRF waves (RF3), the experiments to overcome this problem have been performed. In preliminary experiments with RF3 and NBI the maximum density of 4x 10[sup 18]m[sup -3] was attained. [ABSTRACT FROM AUTHOR]

Performs charge-exchange neutral particle measurements on electron cyclotron resonance heating experiments in hot-ion-mode plasmas of the GAMMA 10 tandem mirror. Description of the experimental apparatus; Temporal behavior of plasma parameters; Evaluation of ion-energy losses; Estimation of ion temperature.

Observes behaviors of high energy ions in the GAMMA 10 tandem mirror. Effective use of the ion cyclotron range of frequency heating; Value of the ion temperature; Observation of pitch angle distribution; Significance of the temporal evolution of the endloss high energy ions; Enhancement of the loss of high energy ions.

Focuses on low frequency fluctuations measured by probes in the GAMMA 10 tandem mirror. Use of electrostatic and magnetic probes; Identification of dominant fluctuations to be flute type and drift type modes; Observation of low frequency magnetic fluctuations; Behaviors of low frequency fluctuations.

An empirical scaling for the potential difference between the plug potential [uppercase_phi_synonym]P and the floating potential [uppercase_phi_synonym]EP of an endplate is obtained in terms of end-loss electron temperatures. Results from the GAMMA 10 tandem mirror [Phys. Rev. Lett. 55, 939 (1985)] indicate that Δ[uppercase_phi_synonym]=[uppercase_phi_synonym]P-[uppercase_phi_synonym]EP scales much better with an effective temperature Teff≡(1-β)TeL+βTeH than with a single temperature TeL or TeH, where TeL and TeH are temperatures of the bulk and the high-energy tail components of the end-loss electrons and β denotes the flux fraction of the TeH component. Moreover, the observed scaling is consistent with a recently developed theoretical model [K. Kurihara et al., J. Phys. Soc. Jpn. 61, 3153 (1992)]. [ABSTRACT FROM AUTHOR]

Strong one-pass absorption of high-power microwaves is observed at the fundamental electron cyclotron resonance in an axisymmetric end mirror of the GAMMA 10 tandem mirror [Phys. Rev. Lett. 55, 939 (1985); Phys. Fluids 29, 2781 (1986)]. The radial profile of microwave power deposition is directly measured without the influence of wall reflection. It coincides with that of the axial flow of warm electrons driven by the fundamental heating as well as with that of the plasma potential at the resonance. This indicates that strong electron cyclotron heating largely affects the potential formation through driving an axial flow of warm electrons. [ABSTRACT FROM AUTHOR]

Hot electrons have been produced by second harmonic electron-cyclotron resonance heating in axisymmetric end mirrors of the tandem mirror GAMMA10 [Phys. Rev. Lett. 55, 939 (1985)] with an on-axis density fraction reaching 80% and temperature of 25–50 keV, satisfying theoretically required conditions for the formation of thermal barriers. The successful control of the electron temperature may be attributed to the relativistic detuning of the second harmonic resonance for localized microwave power absorption. The time evolutions of relevant parameters are studied with extensive diagnostics. [ABSTRACT FROM AUTHOR]

Discusses the use of a semiconductor detector for the measurement of high energy end loss ions from a tandem mirror. Calibration of energy sensitivity to protons; Use of a monochromatic ion source found to be the same as that to electrons; Spread of the energy end loss ions with time; Unknown loss processes that are relevant to ion end loss.

Examines the relation between the distribution function of the ions confined in a tandem mirror and the current-voltage (I-V) characteristics of the end loss ions collected on a gridded energy analyzer. Representation of ion distribution in the loss cone by the decay parameter; Reproduction of the I-V curve from the model distribution.

Analytical investigations are made of perturbed orbits of particles under externally applied wave fields. An equation for radial transport associated with orbit perturbations is derived by assuming stochastic wave–particle interactions in a magnetic mirror field geometry. A Monte Carlo simulation code is developed in flux coordinates in order to study the radial transport numerically. It is found that the results of the analytical and numerical studies are consistent with each other. An important conclusion is that the radial transport resulting from orbit perturbations is not large in present-day tandem mirror experiments. [ABSTRACT FROM AUTHOR]

Proposes the idea of the thermal barrier in order to improve the severe technological requirements of the plug in the original tandem mirror. Plug potential with continuous axial profile; Plausible ion and electron distribution functions in a present tandem mirror; Electron cyclotron resonance heating.

Evaluates thermal dikes which employs electron cyclotron resonance heating (ECRH) in the magnetic and potential configurations appearing in tandem mirrors and tokamak diverters. Heating response function; Substantial power gain; Expression for the electron flux.

Existence of the bounced ion by the plug potential (PP) bounce ion is essential in order to improve the ion confinement in the tandem mirror. The trajectories of the PP bounce ion were calculated on the assumption that the equipotential surface was slightly deviated from the equilibrium state, and it was found that the radial electric field affected the radial transport of the bounce ion. A charge exchange neutral particle analyzer was located at the inner mirror throat region as a bounce ion measurement device. The energy distribution function of the bounce ion was measured using the device, and compared with the energy distribution function of the end-loss ion. [ABSTRACT FROM AUTHOR]

Describes the first of suppression of secondary electron emission (SEE) by using a mesh placed on an endplate of GAMMA 10 tandem mirror. Dependence of the potential in the end region on the bias voltage; Confinement region of the GAMMA 10 device; Prediction of a potential model for the open magnetic field configuration.

Discusses the formation of electrostatic plug potential which is usually observed in a tandem mirror experiment without neutral beam injection in the plug region. Requirement of the heating of the electron cyclotron resonance experimentally; Creation of the plug potential in a tandem mirror without passing ions.