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Carbonization was successfully applied to Heliotron-E. Iron-inpurity radiations were strongly reduced with the carbonized wall. Main impacts of the metal reduction on plasma behaviors are sustainment of stored energy during high power, long pulse heating by NBI, achievement of a quasi-steady discharge with a low helical field and high beta, and highest electron density with pellet injection in a quasi-steady state. Hydrogen recycling was very high with the carbonized wall and low density operation was impossible. Helium glow discharge was found to be effective to control the hydrogen recycling with a carbon-tiled wall.

A plasma current is initiated and raised to a quasistationary level of about 20 kA by injection of the lower hybrid wave into a cold and low-density plasma produced by electron cyclotron resonance. The plasma current rises more slowly than the experimentally obtained L/sub p//R/sub p/ magnetic diffusion time of the bulk plasma. The current rise time is inversely proportional to the bulk electron density, and agrees well with the collision time of the current-carrying high-energy electrons with the bulk plasma.

In this paper, the three-dimensional transient thermal stress problem in a transversely isotropic semi-infinite circular cylinder subjected to an asymmetric temperature distribution on the end surface and convective heat losses into the surrounding medium from the surfaces is analyzed by means of the modified transversely isotropic potential function method.

The subject treated in this paper forms a part of a more precise thermomechanical consideration in designing of rolls in the continuous casting plant at the iron manufacture. From an analytical point of view, a fundamental problem in rolls is reduced to the problem of solving the transient thermal stress in a hollow circular cylinder due to a rotating arc heat source with a constant angular velocity. Numerical results are given for the thermal stress distribution in actual rolls.

In the Heliotron-E device, carbonization experiments were successfully performed by using a DC glow discharge in a mixture gas of hydrogen and methane. The properties of carbon films produced on surface probes were analyzed by Auger Electron Spectroscopy (AES), X-ray Photoelectron Spectroscopy (XPS) and Raman Spectroscopy (RS). Film thickness varied between 17 and 40 nm, and almost no metal impurities were found in the film layer. Both the radial and the toroidal distributions of the film thickness were analyzed. The toroidal uniformity of the carbon film was within a factor of two. The structure of carbon film produced in Heliotron-E was amorphous carbon, while that of TEXTOR film was a mixture of amorphous and graphite. According to the depth profile analysis, the carbon film could hardly be eroded by main discharges. But D2 or He discharge cleaning effectively removed the film. In addition, after the main discharge with Ti-flashing in the carbonized chamber, the formation of TiC in the film region was observed.

This paper concerns a transient thermoelastic contact problem in a transversely isotropic infinite cylinder inserted into a heated rigid ring. It is assumed that the heat transfer coefficient at the bonded surface is different from the coefficient at the traction-free boundary surface. A finite difference formulation with respect only to time is used to solve the three-dimensional transient heat conduction equation for the temperature field. The thermal stress field is analyzed by means of the transversely isotropic potential function method. The radial, hoop and axial stresses have singularities at the end of the contact surface. The concentration factors that may be used to evaluate the strength of the stress singularities are introduced.

This paper discusses the features of the design, test, manufacture and installation of 230 kV self-contained oil-filled (OF) cables and the system installed underneath a bridge crossing the mouth of Lake Maracaibo in Venezuela.

This paper discusses the features of design, test, manufacture and installation of the, 525 KV self-contained oil filled (OF) cable and its system installed at the third powerplant of the Grand Coulee Dam.

As a back‐up experiment for investigations on first‐wall carbon coatings of toroidal machines, we constructed the RIKEN ECR‐2 device and carried out simulation experiments. By electron cyclotron resonance discharges we obtain an amorphous, hard, and dense carbon film. It is possible to decrease the atomic H/C ratio of carbon films by high‐energy ion bombardment. Harmful carbon films deposited on observation windows can be cleaned up by a local pure hydrogen plasma.

The first biased limiter experiment has been done in Heliotron E, which is a typical stellarator / heliotron type device. This experiment investigates the boundary physics of the currentless plasmas, which are produced in the magnetic limiter (divertor) configuration. We analyze the experimental results related to the surface potential, recycling process, and plasma parameters using a material limiter which was biased from the vacuum chamber. The boundary density profile was measured by a thermal Li beam probe to investigate the effect of the biased limiter.

The confinement of ohmically heated stellarator plasma is studied experimentally. The energy confinement time ?E increases with the total rotational transform angle ?? in the case of ??/2? 4, while ?E decreases with ??/2? > 0.3, that is, q?(a) < 3-4, which is consistent with the Alcator scaling. When the rotational transform angle due to helical field ?h/2? is larger than 0.14, no major disruptions are observed even for q?(a) as low as 1.7 (?h/2?= 0.14, Ip ? 100 kA at Bt = 2.2 T), although strong MHD oscillations with low frequency (~1 kHz) appear when q?(a) < 2. Tangential injections of neutral beams are carried out for additional heating of stellarator and tokamak plasmas. With co-injection, the increase in ion temperature ?Ti at the center per injected power PN into the torus is 1.6 eV/kW in the stellarator and is 1.9 eV/kW in the tokamak configuration. In the case of counter-injection, ?Ti/PNis 1.6 eV/kW in both configurations. Lower hybrid heating (LHH) with the frequency of 0.8 GHz is applied. In both cases of stellarator and tokamak, ion heating of 0.8 eV/kW is observed with input power up to 160-180 kW. Electron cyclotron heating (ECH) by use of klystrons with frequency of 35.5 GHz is carried out. Preliminary results show heating of bulk electrons with the heating efficiency of 1.6 eV/kW. Current drive in steliarator plasma by lower hybrid wave is observed in the case of low density plasma (n?e ~5 × 1012 cm-3).

This paper is a theoretical analysis of the thermoelastic effect upon accuracy in the machining of metals. The problem is reduced to the unsteady thermoelastic analysis of a solid cylinder heated on the surface axisym-metrically by a moving heat source under an axial restraint. The thermal and elastic distortions of the workpiece are computed, and the error in the shape is plotted. The authors are grateful to Mi. Ishikawa and Mr. Omichi for their computer calculations. Professor Takeuti's mailing address is Department of Mechanical Engineering, University of Osaka Prefecture, Mozu, Sakai, 591, Japan.

After several hours of discharge cleaning, it has been observed that the decay time of the water‐vapor partial pressure changes from one well defined value to another. A long decay time observed in the later phase can be interpreted as a result of a slow deoxidization rate of chromium oxide, which may dominate the cleaning process in this phase. Optimization of the electron density for the cleaning is discussed, comparing the experimental results on density dependence of the water‐vapor partial pressure with a result based on a zero‐dimensional calculation for particle balance. One of the essential points for effective cleaning is found to be raising the electron density of the plasma high enough that the dissociation loss rate of H2O is as large as the sticking loss rate. A density as high as 1011 cm−3 is required for a clean surface condition where sticking probability is presumed to be around 0.5.

A gas analysis station (GAS) with a quadrupole type gas analyser has been installed on the vacuum pumping chamber of Heliotron-E. The GAS was used to observe the partial pressures of methane and hydrogen during carbonization and subsequent decarbonization of the vacuum wall. From the changes in partial pressures both the carbon deposition rate on the wall and the erosion rate of the carbon film were estimated. In plasma density control studies the GAS was used to investigate hydrogen recycling during conditioning of the carbon wall with both DC-glow and main discharges in helium. The time evolution of the partial pressure of hydrogen induced by discharges in helium indicates that three effects are involved in the recycling process: immediate desorption of hydrogen from the surface of the vacuum wall, readsorption of the desorbed hydrogen, and moderate desorption of hydrogen diffusing from the sub-surface.

This paper describes the design, construction, and results of loading test of the Shigi-Shikitsu line of The Kansai Electric Power Co., Inc., in Osaka, Japan.

In this paper, the transient thermal stress problem for an orthotropic thin plate with a Griffith crack perpendicular to the surfaces of the plate is considered. It is assumed that the transient thermal stress is set up by the application of heat flux to the surfaces of the crack and the heat exchange by convection on the surfaces of the plate. The analytical solution is found by Airy stress function. Numerical results indicate a dependence of the orthotropic stress intensity factors on the thermal and elastic constants over a certain parameter range.

The energy confinement characteristics of ICRF-heated Tokamak plasmas are studied at high input power density approximately 2 MW m-3 volume averaged, on the JIPP T-IIU device (R=0.91 m, a=0.23 m). High electron and ion temperatures (Te approximately 2.5 keV, Ti approximately 2.0 keV, at each maximum) have been achieved by the operation at a plasma current IP of 280 kA, plasma line-averaged electron density ne of 7*1013 cm-3 and input power of 2 MW, with a suppression of total radiation loss (30-40% of the total input power) by a carbon coating on the vacuum vessel. The fraction of ICRF power absorbed by the plasma, alpha , is determined experimentally from the decay of the stored plasma energy just after the ICRF pulse is terminated. The value of alpha increases slightly with increasing electron density and decreases from 90 to 70% as the ICRF power is increased from 1 to 2 MW m-3 volume averaged. The global energy confinement time tau epsilon , defined by WP/(POH+ alpha Pr.f), decreases by a factor of 2 approximately 3 from that in Ohmic plasmas as the heating power increases up to 2 MW. It is found that the energy confinement time has a strong line-averaged electron density dependence as tau E varies as ne0.6, which is obtained by the use of the measured absorbed power, while the Kaye-Goldston scaling predicts tau E varies as ne0.26.

In designing some types of fuel elements, it is necessary to find the thermal stresses in a continuous medium performated by cylindrical channels of circular cross-section. In order to set up the problem, assume that the strength and heat transfer calculation are based on the phenomena that occur in a typical unit lattice cell, and that the heat generation is uniform over the whole section: Therefore, the problems reduce to solve the temperature and thermal stresees in a polygonal prism with a central circular hole under uniform heat generation and for insulated outer boundary. In out previous papers we obtained the steady thermal stress distribution in such formed regions by use of the five elementary functions method. In starting up or shutting down of the reactor, however, the problem becomes one of the unsteady state. It is felt that no analysis has been given to the transient thermoelastic problem of the multiply-connected region. The problems considered here are concerned with unsteady thermal stresses in a polygonal prism with a circular hole under a uniform heat generation. The solving process is divided into two basic steps. First, the heat conduction equation is solved by the technique of Laplace transform. Secondly, the plane thermoelastic problem is solved by use of the five elementary functions method. Throughout the treatment of both problems, in order to satisfy the boundary conditions, we use the point-matching technique in conjunction with the least square method.

The edge plasma physics and the particle control under the intrinsic magnetic limiter configuration of a helical system have been studied with the Heliotron-E device, where currentless plasmas of Te ≤ 1–2 keV, Ti ≤ 1 keV and ne ≤ 2 × 1020/m3 are produced by a combination of ECRH, NBI and/or ICRH. It is indicated that the separatrix region of the heliotron device is able to act as a divertor magnetic field. According to calculations of the magnetic field line in the edge region, the separatrix region has some different characteristics from the scrape-off layer in tokamak devices; the existence of a fine structure in the separatrix region and asymmetry of the region in toroidal and poloidal directions are observed. A localized pattern of the heat load on the first wall is experimentally observed. This agrees with the heat-load profile expected from the magnetic configuration and the distribution of the plasma in the edge region. A carbonization of the first wall is successfully applied to the Heliotron E device for reduction of metallic impurity contents. The heat load at the divertor trace decreased and that on the other part of the first wall increased in the high recycling conditions after the carbonization.

In 1969, we started R & D on a polypropylene laminated paper (PPLP) as a new low-loss insulating paper for oil-filled (OF) cables. Through the material research and the trial manufacture of 215 kV OF cable and four years of long-term field test, PPLP has reached the stage of commercial use.

The present work is concerned with the steady state two-dimensional thermal stress problems in a thick circular cylinder having a polygonal hole under an uniform heat generation having thermally insulated outer boundary. In the present problems, the analysis is carried out by using the complex variable approach proposed by Gatewood. Thus, we may show that the present method yields reliable solution at the inner boundary, because of the sufficient satisfaction of the temperature and traction boundary conditions at the inner boundary. Die vorliegende Arbeit beschaftigt sich mit dem zweidimensionalen Problem des stationaren Warmespannungszustandes in einem dicken Kreiszylinder, der eine gleichformig aufgeheizte polygonale Offnung hat und dessen ausere Begrenzung thermisch isoliert ist. Die Untersuchung bedient sich, wie von Gatewood vorgeschlagen, der Methode der komplexen Veranderlichen. Diese Methode liefert, wie gezeigt wird, fur die innere Berandung eine vertrauenswurdige Losung, da sie die Temperatur - und die Randbedingungen fur den Zug am Innenrand in hinreichender Weise befriedigt.

In autophagy, which is an intracellular degradation system that is conserved among eukaryotes, degradation targets are sequestered through the de novo synthesis of a double-membrane organelle, the autophagosome, which delivers them to the lysosomes for degradation. The core autophagy machinery comprising 18 autophagy-related (Atg) proteins in yeast plays an essential role in autophagosome formation; however, the molecular role of each Atg factor and the mechanism of autophagosome formation remain elusive. Recent years have seen remarkable progress in structural biological studies on the core autophagy machinery, opening new avenues for autophagy research. This review summarizes recent advances in structural biological and mechanistic studies on the core autophagy machinery and discusses the molecular mechanisms of autophagosome formation.

Fast-wave and slow-heatings have been performed to study the heating properties, and to study the confinement properties of plasmas in a rare collisional regime. For the fast-wave (minority) heating, ion temperature increased from 200 eV to 650 eV at an electron density of 2.2 x 10/sup 19/ m/sup -3/ at an ICRF power of 1.5 MW. With the carbonization of the vacuum chamber, the ICRF pulse became able to sustain the plasma for 100 msec without ECH pulse. For the slow-wave (Ion Cyclotron Wave) heating, T/sub i/ increased up to 1.e keV at n-bar/sub 6/ of 0.6 x 10/sup 19/ m/sup -3/. The ion heating strongly depended on the electron density and better ion energy confinement was observed at high electron temperature region. These results were consistent with the calculation of the ambipolar neoclassical diffusion in the rare collisional regime. This high T/sub i/ and T/sub e/ plasma condition possibly corresponds to the electron root with a positive radial electric field E/sub r/.

ACO occurred within 40 min (mean 15.7 min) after PTCA in 22 patients and more than 12 hours in 2. The group with ACO had a significantly higher incidence of female (46% vs 23%), acute myocardial infarction (63% vs 35%), eccentric lesions (73% vs 28%), tortuous lesions (30% vs 4%) and coronary dissection or intraluminal haziness (89% vs 34%). Luminal narrowing before and after PTCA was significantly higher in ACO group than in control group (93% and 56% vs 87% and 23%). Repeat PTCA was performed in 17 patients and was successful in 13. Coronary bypass surgery was performed in 4 patients. Intracoronary urokinase was ineffective to ACO. In 3 autopsy cases dying 5, 14 and 17 days after PTCA, large extent of intimal tears and thrombus in the space of tears and the lumens were observed. These results suggest that coronary dissection chiefly contributes to ACO and coronary thrombosis is superimposed for a secondary event in most of cases with ACO.

Current drive by fast magnetosonic waves is successfully performed in the JIPP T-IIU tokamak by means of a four-element dipole antenna array with a Faraday shield. A plasma current of about 50 kA is sustained by an RF power of about 80 kW in a low-density plasma (3 x 10/sup 12/ cm/sup -3/) with an efficiency comparable to that of slow wave current drive. A density limit for fast magnetosonic current drive is observed contrary to theoretical expectations based on linear wave propagation.

Chromosome studies were conducted on two patients with adult T-cell leukemia. In both patients, a marker chromosome 14q+ and a structural change involving chromosome 1 with trisomy of the q arm were found in peripheral blood leukocytes. The 14q+ marker chromosome had resulted from translocation from #5p in one patient and #5q in the other patient. The present and previous studies suggest that the donor chromosomes involved in the 14q+ translocation are variable. This indicates that the 14q+ marker chromosome rather than the donor chromosome is intimately related with adult T-cell leukemia.

In the Large Helical Device (LHD), upgrading of the key hardware system since the last EPS conference has led to (1) higher Te (Te(0) = 4.4 keV at ne = 5.3×1018 m-3 and Pabs = 1.8 MW); (2) higher confinement (τE = 0.3 s, Te(0) = 1.1 keV at ne = 6.5×1019 m-3 and Pabs = 2.0 MW); (3) higher stored energy Wpdia = 880 kJ; and (4) the highest β value in helical devices (2.4% at B = 1.3 T). The energy confinement was systematically higher than that predicted by the International Stellarator Scaling 95 up to a factor of 1.6. Ion cyclotron range of frequencies (ICRF) power up to 1.3 MW was reliably injected into the plasma without significant impurity contamination and a plasma with stored energy of 200 kJ was sustained for 5 s by ICRF alone. Long pulse discharges greater than 1 min in duration have been successfully achieved with ICRF power alone and with neutral beam injection (NBI) power alone. With NBI heating an 80 s discharge was achieved with a heating power of 0.5 MW at 2.75 T. The electron density was maintained at around 1.6×1019 m-3 by controlled gas puffing. The central electron and ion temperatures were kept around 1.5 keV. With ICRF heating, a similar long pulse discharge was achieved for 68 s with a heating power of 0.85 MW. The sustained plasma parameters are: Wp~110 kJ, Te(0)~Ti(0) = 2.0 keV and ne = 1.0×1019 m-3. During these discharges, no increase in radiation power has been observed.

To test the performance of tungsten as a plasma facing material, a small test limiter made of solid pure W was immersed in a TEXTOR plasma. A surface temperature in excess of 3000 K and the rate of temperature increase close to 2000 K/s was measured for the auxiliary heating conditions. These values corresponded to a power flux density of more than 40 MW/m 2 based on the calculations of a heat transfer model. The test limiter showed no observable degradation after exposure to this high heat flux density. The oxygen flux from the test limiter showed an increase during intense plasma exposure. However, no enhancement in the normalized W yield was observed when the W release was normalized to the C and O flux to the limiter, and the W release appeared to be dominated by physical sputtering.