Pulsed high voltage was applied to logs used for mushroom culturing to mushroom growth. An experiment was carried out in an attempt to increase shiitakemushroom yield. Results showed that theweight of shiitake mushroom yield was double that of a normal group cropped in a month. Another experiment was performed to estimate the effect of electrical stimulation on the growth of hyphae. Results of that experiment showed a slight influence on the growth of hyphae, and showed some possibilities thismethod can improvemushroom culturing techniques.
This report discusses the various problems which are encountered when a crystal spectrometer is used for the purpose of observing polarized x-ray lines. A polarimeter is proposed based on the novel idea of using two series of equivalent atomic planes in a single crystal. The present status of the astronomical x-ray detection techniques are described with emphasis on two dimensional detectors which are polarization sensitive.
An intuitive account is given of the polarized emission line of atoms and ions, both classically and quantum mechanically. Polarization is a result of the population imbalance among the magnetic sublevels, or of the alignment, in the upper level. The history of Plasma Polarization Spectroscopy (PPS) is reviewed. Various polarization phenomena are divided into three classes. For each of the classes, typical experiments undertaken so far are reviewed. The advantages, limitations, and challenges regarding PPS are discussed.
第1章でお約束しましたように, 非線形プラズマ実験について討論会を行いました. まず始め に, 各執筆者から内容の説明と今後の課題について10-15分程で話していただきました. 一部の 方を除いて殆どの執筆者が参加され, また, 編集委員会からも参加していただき, 討論会は大変 盛りあがりました. 発表内容はテープにとり, できるだけ討論会の雰囲気が読者に伝わるように 書いておりますので, 学会誌として表現が悪い所があるかもしれませんがお許し願います.
The principle of D-3He fueled fusion which mitigates engineering problems attributed to 14 MeV neutrons is presented as well as the requirements needed to constitute an attractive D-3He fusion reactor. The intrinsic characteristics of a field-reversed configuration appears to meet the requirements. Potential and critical issues are discussed on the bases of a comprehensive D-3He fueled FRC reactor design “ARTEMIS”, which definitely offers the most attractive prospect of the energy development for the 21st century: It is inherently safe and environmentally acceptable in view of radioactivity and fuel resources. Further, the estimated cost of electricity is low compared to a light water reactor. An experimental research program needed to develop the D-3He fueled FRC fusion reactors is discussed.
We review the sheath which is produced around a moving object in space.The sheath in space is grouped from different point of view; one is ambient plasma density, another is potential of the object. In terms of the ambient plasma density, neutral particles collide with electrons inside the sheath in the lower ionosphere below 90km. Shape of the sheath which is formed around moving object are distorted which is totally different from stationally laboratory plasma.In the high altitude, where ambient plasma density is less than 103els/cc, the satellite is surrounded by photoelectron in the sunlight.When we look at the sheath from the view point of the magnitude of the voltage applied to it, the sheath is divided into two groups; low voltage and high voltage regimes. Low voltage regime is a conventional satellite sheath. High voltage regime is encountered in bombardment of the spacecraft by auroral electrons under low density plasma or in electrodynamic tether system. Study about the highly biased large electrode is important for the future solar power station.
The relation between the Hamada and the Boozer magnetic coordinate systems is clarified by deriving them from a general magnetic fied coordinate system. The coordinate transformation from the Hamada to the Boozer coordinate system is performed using a transformation function, which is easily calculated with the knowledge of the magnetic field strength only.In non-axisymmetric systems, the Fourier spectrum of the magnetic field strength |B| in the Hamada coordinate system is broader than that in the Boozer coordinate system and the leading modes of IBI in the Hamada coordinate system significantly deviate from a simple model field in comparison with the Boozer coordinate system.The Boozer coordinate system is suitable for numerical calculations, especially, for neoclassical and orbit calculations in non-axisymmetric systems.
Tokamak D-T power reactor with day-long operation is investigated, where plasma current is driven inductively.Thereby the high power multiplication factor (typically Q>1, 000) is attained easily.For day-long operation only with the use of inductive current drive, the large plasma major radius is necessary to provide sufficient magnetic flux in the Ohmic transformer.Parameters of tokamak reactor for day-long operation are typically major radius 12m, minor radius 1.5m with elongation ratio1.6 and triangularity0.5, toroidal mag netic field12.5T, and plasma current 8.7MA.Plasma volume is comparable to the current-driven reactors, such as SSTR and ARIES in spite of large major radius, because the aspect ratio is relatively high.
With the plasma temperature, collisions plays a different role on the basic characteristics of the plasma such as the transport and the MHD activities.Behaviors of plasmas are surveyed in a view point of collisions to understand different aspect on the basic characteristics of plasmas with various temperatures.
High energy density plasma is shortly introduced, i.e.what is high energy density plasma?, how to produce it?, what kinds of its application can we expect?, and also recent experimental results are briefly discussed.
Introducing period ratio δ, the thermal efficiency of a periodical thermonuclear fusion reactor is studied. The moderate temperature of the coolant has no choice but to be low because of the small δ at present and the heat resistivity of materials. To overstep the ignited plasma criterion and to keep an adequate efficiency as a heat engine, the large power density is necessarily demanded. To reduce power density, continuous combustion (δ=1) is expected.
Ohmic ignition condition on axis of the DT tokamak plasma heated by minor radius and major radius adiabatic compression is studied assuming parabolic profiles for plasma parameters, elliptic plasma cross section, and Neo-Alcator confinement scaling.It is noticeable that magnetic compression reduces the necessary total plasma current for Ohmic ignition device.Typically in compact ignition tokamak of the minor radius of 0.47m, major radius of 1.5m and on-axis toroidal field of 20T, the plasma current of 6.8MA is sufficient for compression plasma, while that of 11.7MA is for no compression plasma. Another example with larger major radius is also described.In such a device the large flux swing of Ohmic transformer is available for long burn.Application of magnetic compression saves the flux swing and thereby extends the burn time.
Contributions to Plasma PhysicsVolume 32, Issue 3-4 p. 389-394 Specific Boundary Effect: Contributed Paper New Method for Broadening Divertor Heat Load by Rotating Perturbed Magnetic Field S. Sakurai, S. Sakurai Department of Electrical Engineering, Faculty of Engineering, Nagoya University Nagoya, 464-01, JapanSearch for more papers by this authorS. Takamura, S. Takamura Department of Electrical Engineering, Faculty of Engineering, Nagoya University Nagoya, 464-01, JapanSearch for more papers by this author S. Sakurai, S. Sakurai Department of Electrical Engineering, Faculty of Engineering, Nagoya University Nagoya, 464-01, JapanSearch for more papers by this authorS. Takamura, S. Takamura Department of Electrical Engineering, Faculty of Engineering, Nagoya University Nagoya, 464-01, JapanSearch for more papers by this author First published: 1992 https://doi.org/10.1002/ctpp.2150320333Citations: 3AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat References Azumi M., Takizuka T. et al. (1990) ITER-IL-PH-13–0-J-5. Breton C., De Michelis C. et al. (1991) Nucl. Fusion 31, 1774. Chu M. S., Jensen T. H. et al. (1991) Report of General Atomic Company, GA-A20682. La Haye R. J. (1991) Nucl. Fusion 31, 1550. McCool S. C., Wootton A. J. et al. (1989) Nucl. Fusion 29, 547. Rechester A. B. and Rosenbluth M. N. (1978) Phys. Rev. Lett., 40, 38. Rutherford P. H. (1973) Phys. Fluids 16, 1903. Shoji T., Fujita T, et al. (1990) in Controlled Fusion and Plasma Physics (Proc. 17th Euro. Conf. Amsterdam), Part 3, p. 1452. Takamura S. et al. (1988) Nucl. Fusion 28, 183. Takamura S. et al. (1990) in Plasma Physics and Controlled Fusion Research (Proc. 13th Int. Conf. Washington D. C.), vol. 1, p. 549 (IAEA, Vienna, 1991). Tamai H., Shoji T. et al. (1991) Report of Japan Atomic Energy Research Institute, JAERI-M 91–110. Tokar M. Z. (1988) USSR Contribution to the INTOR Phase Two A. Part III Workshop, Rep. Kurchatov Institute, Moscow, p. 99. Wesson J. (1987) “ Tokamaks”. Clarendon Press, Oxford, p. 151. Citing Literature Volume32, Issue3-41992Pages 389-394 ReferencesRelatedInformation
Reactive plasmas generated by discharge decomposition of various molecular gases have been used in many fields of industry for thin film electronic devices, new material, gas laser and so on.This paper reviews (i) what aspects of a reactive plasma are distinctive in comparison with other plasmas, (ii) what parameters of the plasma are needed to be controlled for industrial applications, (iii) how deeply the reactive plasma has been understood in view of basic physics and chemistry, and (iv) what innovative techniques of plasma production and control have been developed.
A tokamak plasma equilibrium code to reconstruct the magnetic field around a plasma from measured magnetic data, was applied to the Hitachi tokamak (HT-2).It was found that a systematic measurement error is produced by the toroidal field coils and it makes an iterative calculation converge to a wrong equilibrium state.A technique to compensate for the measurement error field was developed.The plasma cross-sectional shape is then well analyzed in the HT-2 experiments.A compensating radial field of around 5x10 -4 T is necessary for a successful equilibrium calculation at a toroidal field of 1T.This value of the compensating field is consistent with the results of the experiments to optimize breakdown.This technique is applicable to all tokamaks.
Anomalously strong optical emission from the excited CH radical was obserbed near the negatively biased electrode in a CH4/Ar glow plasma. The time evolution of the CH emission depends on the material and the surface state of the electrode as well as the applied bias voltage. A possibility of the anomalous emission by secondary electrons was denied from Monte Carlo simulation of the process. The experimental observations and calculations revealed the CH radical formation by two surface processes: fragmentation of hydrocarbon particles (ions and neutrals) at their impact on the cathode, and sputtering of the already deposited carbon film. These processes are essential for understanding the redeposition mechanisms in carbonized environement.
