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The Pummerer rearrangement of 1-deoxy-5-thioglucopyranose derivatives carrying acetonides at the C3,4-positions proceeded regioselectively at the C1 position by treating with TFAA in the presence of pyridine. Studies employing deuterium-labelled derivatives revealed that the reaction was induced by E2 1,2-elimination of trifluoroacetic acid of the trifluoroacetoxy sulfonium intermediate. This methodology was applied to the synthesis of an isomaltotriose derivative consisting of 5-thioglucopyranoside units.

The Pummerer rearrangement of 3,4-O-isopropylidene-1-deoxy-5-thiopyranose oxide derivatives took place at the C1 position regioselectively to give the corresponding 5-thiopyranoses. The reaction mechanism of this reaction is also discussed.

A low energy (0.2–3 keV) fast neutral lithium beam source based on a glassy β-eucryptite Li+ source was developed for high spatial resolution (0.5 cm or less) density profile measurements in edge plasmas of tokamaks and stellarators. A 10-fold higher Li+ emission was obtained from this source as compared with the traditionally used pasty sources. Space charge effects became important for the ion beam propagation at such low energies, requiring careful beam control between the accelerator and the neutralizing section. In spite of this shortcoming, an approximately 40 μA cm−2 equivalent current Li0 beam at about 2 keV was obtained.

Negative sodium ions (Na − ) were extracted from a small multi-cusp ion source. A steady state sodium plasma was produced by primary electrons in a sodium gas evaporating from a metal sample placed in the discharge chamber. The Na − current density of 1.5 μA/cm 2 was obtained from a single aperture of 1.5 mm diameter at relatively low discharge power of about 0.4 W and filament power of 50 W. Extraction characteristics were studied by changing the plasma electrode bias. The extracted Na − current showed a dependence on the bias voltage similar to that of H − or Li − volume production.

A gas chromatographic procedure has been developed for determination of chlordanes in environmental samples such as soil. The basis of the method is the conversion of many of these chlorinated C10 hydrocarbons into a single partial dechlorinated product, which is determined by gas chromatography with an electron capture detector. Soil is extracted with hexane. The extract is cleaned up on a Florisil cartridge and dechlorinated with Zn/HCl. The dechlorinated compound is injected into a gas chromatograph and chlordanes determined as one partially dechlorinated compound. The detection limit in this method is 0.002 μg/g. The coefficient of variation was 3.2% for soil samples while the average recovery was 94.3%. Although capable of determining only 4, 7-methanoindanes, which comprise more than 80% of the chlordanes, the significance of the method is recognized as the first means of screening for chlordanes. To date application has been made only to soil samples, but it is believed that with selection of the proper solvent for extraction, the method can be more broadly applied to samples such as food and biological samples.

Diatomic negative ions of Na(Na2 -) are extracted with atomic negative ions of Na(Na-) from a low-temperature Na plasma. The extracted currents of these negative ions are experimentally measured as functions of discharge parameters and wall temperatures. The measured extraction characteristics are discussed by comparing the results with those of negative hydrogen and negative lithium ions extracted from the corresponding plasmas. The maximum current ratio of Na2 - to Na- for a wall temperature below 235°C is on the order of 0.01, much smaller than that obtained in the sputtering experiment.

A heavy neutral beam probe was developed for simultaneous measurements of local space potential and density fluctuations in a plasma. It was applied to both electron cyclotron heated (ECH) and radio frequency heated (RF) plasmas in the bumpy torus NBT-1M, and the feasibility of this method was successfully demonstrated by observing a low frequency m=1 interchange mode which was rotating poloidally at a frequency near the E×B drift frequency. It was shown that use of this probe results in extension of the range of fluctuation measurement by beam probe technique to relatively low temperature plasmas. It is applicable to a plasma with a strong RF field with which Langmuir probes cannot be used.

The energy distribution of Au- extracted from a plasma-sputter type negative ion source was measured. The energy spread ΔE, which was defined as the FWHM of the observed negative ion energy distribution, increased with increasing target voltage (V t). When V t was about 280 V, the energy distribution agreed well with the Thompson-Sigmund (T-S) theory. For values of V t less than 280 V, the high-energy component in the distributions fell off faster than those predicted by the T-S theory. This effect was exaggerated as V t was further decreased. The ΔE for V t below 280 V are less than 10 eV, which seems to be sufficiently small for application to a heavy ion beam probing (HIBP) method.

A method to measure the work function of the target surface in a plasma-sputter-type negative ion source has been developed. The method can determine the work function by measuring the photoelectric current induced by two lasers (He-Ne, Ar+ laser). The dependence of Au- production upon the work function of the target surface in the ion source was studied using this method. The time variation of the target work function and Au- production rate were measured during the cesium coverage decrease due to the plasma ion sputtering. The observed minimum work function of a cesiated gold surface in an Ar plasma was 1.3 eV. At the same time, the negative ion production rate (Au- current/target current) took the maximum value. The negative ion production rate indicated the same dependence on the incident ion energy as that of the sputtering rate when the work function was constant.

A high-temperature radiation source has been developed for the absolute calibration of diagnostic instruments for measuring electron cyclotron emission from high-temperature plasmas. The source has a radiation area of φ 150 mm and can be heated up to 500°C. The measured emissivity of the source is close to unity in the spectral region between 200 and 500 GHz. The grating polychromator has been calibrated using the radiation source developed. The obtained temperatures agree with those by the pulse height analysis of soft X-rays and Thomson scattering measurement within 10%.

Data of JIPP T-II ICRF heating experiments are presented. The experiment covers three typical cases: the low-concentration hydrogen minority case, the high-concentration hydrogen minority case, and the 3He-minority case. The best heating efficiency is obtained for the 3He-minority case. It is shown through power balance analysis that the two H-minority cases are different in the wave energy deposition profile. The difference is explained by the presence of a local cavity mode in the high-concentration minority case. The ion temperature stops rising at a power density level of 0.65 W-cm−3 for the hydrogen minority experiments. No such deterioration is found in the case of the 3He minority experiment up to a power density level of 0.45 kW-cm−3. This is the maximum possible to attain within the maximum power injection (180 kW) up to which the experiment is conducted. An analytic solution of the Fokker-Planck equation is derived in order to interpret the deterioration of the heating efficiency.

The surfaces of TiC (20 μm) coated limiters were investigated after four-month plasma exposure with tokamak and stellarator type discharges in JIPP T-II. Three types of surface damage were observed as 1. 1) a large melted spot having many macrocracks, 2. 2) a large exfoliated surface of the coating and 3. 3) a color changed region without exfoliation of the coating. The position of damages observed on the ring limiters and the rail limiter revealed that the damages of 2) and 3) were associated with the asymmetric cross-sectional shape of the stellarator type plasma. The quantitative AES analysis was performed for identification of surface impurities (Si,P,C, etc.) transported from the plasma and for depth composition analysis of the limiters. It was found that C atoms were depleted from the subsurface region and 0 atoms accumulated to produce a thick Ti-oxide layer (1500 A). The thickness of the oxide and the amount of retained Fe atoms in the subsurface region were also found to be associated with the asymmetric shape of stellarator type plasma.

The technique of laser fluorescence spectroscopy (LFS) was exploited for the study of surface phenomena during ion-beam bombardment by observing the transient change of the velocity distribution functions from pure iron and iron-oxide targets. It was shown that the surface binding energy of compound as well as pure materials could thus be measured. In addition, the LFS technique was expanded to the VUV region by observing the fluorescence signal of carbon atoms sputtered from a graphite target.

For the measurement of a profile of spectral line, a high dispersive monochrometer with an Echelle-grating and 12 channels of photoelectric devices using thin glass sheets, to separate the line profile are constructed. The measured resolving power is about 2×105 and the linear dispersion at the image plane is 1.2 mm/A. This instrument is applied to measure the ion temperature of MACETIE device by using the line of He II 4686 A.

Spatially resolved Fe Kα spectra in the wavelength range of 1.7–2.0 A (FeII‐XXVI) and 1.91–1.95 A (FeII‐XIX) are first observed in a single shot with low‐resolution Johansson and high‐resolution Johann type crystal spectrometers, respectively. The spectra show the evident proof that the vacuum spark plasma has two different structures. One is a thermalized point plasma (≲10 μm) with high temperature (Te ∼2 keV) and high density (ne ∼1021 cm−3). The spectrum contains x‐ray lines from FeXXIII‐XXVI. The other is an extended plasma (∼3 mm) associated with nonthermal electrons, where the region of intense emission of Kα lines from FeIII‐XX shifts toward the cathode with the increase of the ionic charge.

A simple diagram method is applied to obtain the time evolution of the electron temperature from the time history of the impurity line radiation which appears during the early phases of lower hybrid current startup in the JIPP T-IIU tokamak. This method makes it possible to survey the dependence of the time behavior of impurity emission on various plasma parameters (impurity influx rate, impurity confinement time, etc.). The electron temperature thus obtained agrees well with that derived from the temperature-sensitive line ratio and from Thomson scattering.

A metal-film bolometer has been developed for reliable measurements of the radiation power from high-temperature plasmas. Its sensitivity and time response were improved by reducing the absorber thickness (10 µm) to the minimum limit in order to sufficiently absorb photons with high energies up to 3 keV. In addition, this detector has well-defined thermal characteristics. The deviation of the measured value arising from thermal cooling was investigated by numerically solving a heat conduction equation associated with the detector. The calculated results could explain the thermal characteristics well for a temporally constant power (at calibration) and showed that the deviation of the measured radiation power from its calculated value could be reduced by a precise correction (to the extent of 0.5%).

The characteristics of four crystals (LiF(200), Ge(220), LiF(220) and Quartz(2023)) for a Johann type crystal spectrometer with Photo Diode Array have been investigated from observations of FeKα1,2 characteristic X-ray. The results are tabulated with their resolution power and relative sensitivities. They were applied also to the X-ray spectroscopic measurements of a high-temperature plasma. The fine structure of the iron oxygen-like Kα lines has been resolved by the Quartz(2023) crystal.

The spatial profiles of electron density in Nagoya Bumpy Torus (NBT) have been measured with a fast neutral Li beam probing, which utilizes the photon emission due to the electron impact excitation of the injected atoms. It is shown that plasmas are well contained inside the hot electron annuli. The attenuation of thermally injected Li atoms has been measured for the estimation of electron density as a cross check.

The characteristics of a Johann-type crystal spectrometer with a photodiode array (PDA) are described. The crystal used is LiF(200) with a bending radius of 100 cm, and the sensitivity of the PDA is measured for X-rays of 4 to 17 key. The collection efficiency η of charges created in the PDA is determined as a function of the X-ray energy E(keV): η=-0.026E+0.68. An asymmetrical spectral profile is observed when a monochromatic X-ray beam is incident on the PDA with an angle larger than 40°. The sensitivity of the spectrometer is also calibrated against a conventional X-ray tube. The PDA is used for the observation of X-ray lines from a high-temperature plasma in a vacuum spark. The resultant Fe Kα spectrum shows a spread over several channels due to blooming, when compared with that recorded on Kodak no-screen X-ray film.

A 10-channel grating polychromator has been developed and applied for the measurements of the second harmonic electron cyclotron emission from the JIPP T-IIU tokamak plasma. The frequency resolution measured at 150 GHz is about 3 GHz which corresponds to the spatial resolution of 1.8 cm near the center of the plasma column. The grating efficiency is about 80% for S-polarization around 160 GHz. Its excellent time resolution, Δt≤2 µs, is favorable for studying MHD activities in hot plasmas. It has been found from the measurements in JIPP T-IIU that the grating polychromator is a powerful diagnostic tool for the measurements of electron temperature of the plasma.

By introducing into the single-collision model a flux-attenuation factor both in the incoming flux and in the outgoing flux, together with a reduced particle energy, we have derived more comprehensive analytical expressions for the number and energy reflection coefficients for all incident-target-atom combinations, leading to a simple explicit representation of the reflection flux under certain approximations. This gives the general qualitative tendency of the light-particle reflection, while a more quantative knowledge should be obtained from computer simulations or analytical approaches including numerical calculation for multiple collisions.

The magnetic field strength has been obtained from the Zeeman splitting. Thermal He atoms, as an impurity, were injected into a low density (n e∼5×1010 cm-3) hydrogen plasma produced by electron cyclotron resonance. A singlet line at 6678 Å from He atoms excited by the plasma electrons splits into a normal Zeeman triplet in the magnetic field. The line profile was measured with a high resolution Fabry-Perot interferometer. This diagnostic allows the determination of the Zeeman splitting at magnetic fields as low as 1.2 kG, lower than which the splitting is masked by the Doppler broadening of the injected atoms.

The efficiency vs operation voltage characteristics of a channel electron multiplier (CEM) with a negative voltage applied to the entrance cone are investigated in detail. In this negative bias operation, an abnormal increase in efficiency with operation voltage is found, arising from two main mechanisms. One is the change in potential distribution in the cone with the applied voltage. This is because the probability of secondary electrons ejected from the cone being pulled into the channel depends on the potential distribution in the cone. The other is the ionization of particles by leakage electrons from the gap between the CEM exit and the electron collector. Methods of solving these problems are also described.

A high-current lithium ion beam of a few mAcm-2 with an energy of 12 keV and a minimum beam divergence of about 1.2° has been produced by using an ion source of the discharge type. Characteristics of the lithium ion beam regarding the intensity and divergence were experimentally investigated in detail. A lithium neutral beam has been produced using a sodium neutralizer. The neutralization efficiency of the lithium ion beam in the energy range of 2–15 keV was about 80% with a neutralizer at a vapor pressure of 1.7×10-3 Torr. A mass analysis was performed when a mixed discharge of lithium and argon was used. The ratio of R (argon-ion current/lithium-ion current) became less than 0.1 at the oven temperature of the ion source to about 700°C. The applicability of a fast neutral lithium beam to plasma probing is discussed.

The spectral line profiles produced by neutral hydrogen atoms have been measured using a high resolution Fabry-Perot Interferometer. The Hα line 6563 Å is found to have an asymmetric profile in non-magnetized and low density plasmas. The line profile calculated taking into account the fine structure of the Hα line shows a reasonable agreement with the experimental results. The atom temperature obtained from the Doppler broadening is about 0.1 eV.

Successful oscillation of a tunable, high-power argon excimer laser is reported. The wavelength was tuned from 124.5 to 127.5 nm with a spectral width of 0.3 nm. The output power of 2.2 MW, obtained at the line center, is 3 orders of magnitude larger than the value reported previously by Wrobel et al. [Appl. Phys. Lett. 36, 113 (1980)]. The possibility of frequency conversion of the argon excimer laser radiation to other wavelengths by a stimulated Raman scattering process is discussed.

Fundamental characteristics of a GaAs Schottky barrier diode mixer have been measured for the purpose of using it as the detector of a twin 118.8 µm CH3OH laser interferometer. The mixer sensitivity for beat oscillations of the twin lasers was measured in a frequency region from 1 MHz to 7 MHz. A signal to noise ratio of I.F. signal over 45 dB is obtained for the frequency up to 6 MHz. The dependence of the mixer sensitivity on local beam power was also measured. The I.F. signal level is approximately proportional to the local beam power in power level from 0.1 mW to 1.2 mW.

The ion temperature profile and the density distribution for the beam penetration in the plasma have been measured and evaluated using emissions produced by the charge exchange reaction between a heating neutral hydrogen beam and fully ionized impurities on the JIPP T-IIU tokamak. A 1 m spectrometer with a multichannel detector is used to detect ultraviolet and visible emissions from this reaction. The ion temperature profile during neutral beam heating (or plus ion cyclotron range of frequency heating) is obtained from the Doppler broadening of emission spectra. The central ion temperature agrees with those from other diagnostics. The beam density profile is also in good agreement with the simulational result. The availabilities are demonstrated on this technique to measure the ion temperature and the beam density profile which are necessary to discuss beam heating efficiency and thermal transport.

N-type indium antimonide shows the photoconductive effect not only in the far infrared, but also in the millimeter-wave region. Millimeter-wave photoconductivity was observed in the 2 mm-wave region to clarify the origin of the effect. It is concluded that, in elements with low carrier concentration, the impurity transition between shallow donor levels is the main process for the photoconductivity, while the hot electron photoconductive effect is small as compared with the impurity photoconductivity. Performances as a millimeter-wave detector are also studied. Signal-to-noise ratio of InSb detector is superior to that of conventional silicon point contact diode. Rise and decay times of the detector without magnetic field are about 0.4 µs and 0.7 µs respectively. This detector is useful even for measurements of incoherent radiation.