Search

Awa-ban tea (Awa, Tokushima prefecture in Japan; ban, “evening” in Japanese) is a type of tea exclusive to the Tokushima area. Awa-ban tea leaves are unique in that they are produced via pickling and anaerobic fermentation. Here, we report the identification and purification of an antioxidant that is specifically present in Awa-ban tea but is absent in green and black tea. The molecule, identified as resorcinol, was found to exhibit radical-scavenging activity in vitro at levels equivalent to those of (–)-epigallocatechin gallate in green tea. Fluorescence microscopy and flow cytometry results further showed that resorcinol decreased the levels of reactive oxygen species in HEK293T cells, human umbilical vein endothelial cells, and Jurkat cells in a concentration-dependent manner. Moreover, the 3-(4,5-di-methylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated that treatment with 10 mM resorcinol did not affect cell viability. Our results indicate that Awa-ban tea has properties that are quite distinct from those of green and black tea and is therefore a unique antioxidant beverage. We also suggest that resorcinol is a novel tea-based antioxidant.

High-energy X-ray diffraction measurements were carried out for liquid 2-aminoethanol (NH2CH2CH2OH, MEA) in order to obtain direct information on the conformation of MEA in the liquid state, in whi...

Growth of neurite processes is a critical step in neuronal development, regeneration, differentiation, and response to injury. The discovery of compounds that can stimulate neurite formation would be important for developing new therapeutics against both neurodegenerative disorders and trauma-induced neuronal injuries. Semisynthetic derivatives of artemisinin, an active compound in Artemisia annua, have been effectively used in malaria treatment, but they have been shown to possess neurotoxic potential. In this study, we found unexpectedly that artemisinin and its derivatives induced neurite outgrowth of PC12 cells. Artemisinins containing an endoperoxide bridge such as artemisinin and dihydroartemisinin induced growth of neurite processes at concentrations that were slightly cytotoxic, artemisinin having the most potent maximal effect among them. Deoxyartemisinin, which lacks the endoperoxide bridge, was ineffective. Artemisinin-treated cells expressed increased levels of the neuronal marker βIII-tubulin. Artemisinin upregulated phosphorylation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK), critical signaling molecules in neuronal differentiation. Consistent with activation of the two MAPKs, neurite outgrowth induced by artemisinin was inhibited by the MAPK/ERK kinase inhibitor PD98059 and the p38 MAPK inhibitor SB203580. Artemisinin also induced phosphorylation of cyclic AMP response element-binding protein (CREB) that was almost completely attenuated by PD98059 but not by SB203580. Taken together, our results indicate that artemisinin and its derivatives containing the endoperoxide bridge induced differentiation of PC12 cells toward a neuronal phenotype and suggest that both activation of ERK signaling pathway, which leads to CREB phosphorylation, and activation of p38 MAPK signaling pathway are involved in this process.

High energy X-ray scattering measurements using synchrotron radiation were carried out for aqueous monoethanolamine, diethanolamine and 2-amino-2-methyl-1-propanol solutions before and after CO2 absorption. Difference distribution functions around captured CO2 were derived by applying a difference analysis method and by subtracting intramolecular interactions within CO2-bound molecules. Otained difference distribution functions showed a peak at r = 0.35 nm for each solution. This peak is attributable to C(CO2)⋯O(water) interaction. It can be concluded that captured CO2 forms hydrogen bond with neighboring water molecules.

The Kansai Electric Power Co., Inc. (KEPCO) has developed energy efficient chemical absorbents and economical processes which aim to reduce the cost of CO 2 capture, in collaboration with Mitsubishi Heavy Industries, Ltd. (MHI). Together the companies have been developing and critically testing high efficiency, economical absorbents according to the latest absorbent development procedures and process simulation for CO 2 capture processes. This work has been ongoing since 1991, using several Japan based R&D facilities and a pilot plant, used to verify improvements, located at Nanko Power Station in Osaka, Japan. Following significant testing of a range of absorbents in the mid 1990s, KS-1 TM , KS-2 and KS-3 were developed. Based on subsequent rigorous evaluation of the three solvents, KS-1 TM was selected for commercialization because of its overall technical and economical merits. During long-term pilot plant testing, the improved absorbents demonstrated superior performance in relation to the regeneration energy requirements leading to the following results: 2.94 MJlkg- CO 2 in combination with KS-1 TM ” and the Kansai Mitsubishi Carbon Dioxide Recovery (KM-CDR Process TM ) commercial process. In addition, practical, commercially applicable improved absorbent properties such as low corrosiveness and low solvent consumption were also confirmed. KEPCO and MHI continue development work in this area and the current status is summarized as follows: The highly successful R&D phase has led to the commercial deployment of CO 2 capture technology and seven (7) commercial CO 2 capture plants are currently under operation, with a maximum CO 2 capture capacity of 450 metric tons per day (tpd). These commercial plants are deployed in the chemical and fertilizer industry, where the operational performance is assisting in the improved development of R&D concepts. Two (2) further commercial plants are under construction, with commissioning expected in Q3 2010. For further cost reductions in relation to CO 2 capture, recent work has focused on developing new energy efficient chemical absorbents and processes. Following modifications to the Nanko CO 2 capture pilot plant a new “Energy Saving Process”, was developed, which leads to a greater than 10% steam consumption reduction over the MHI conventional process using KS-1 TM absorbent. Additionally the same reduced steam consumption was recorded for tests using the KS-1 TM absorbent. A thermal energy requirement of less than 2.5 MJ/kg- CO 2 in combination with KS-1 TM and the “New Energy Efficient Process” has been confirmed under the optimum operation condition of the CO 2 capture process. In addition to select new absorbents which feature the best profile and fit to the actual operating condition, KEPCO and MHI have intensively evaluated vapor-liquid equilibrium (VLE) and reaction kinetics for a range of newly developed absorbents and their performance is presented in this paper. The above data was obtained using the Nanko CO 2 capture pilot plant which operates under a natural gas fired boiler condition and we expect that the thermal energy requirement of coal fired boiler flue gas (with greater CO 2 concentration condition) will be further reduced. KEPCO and MHI are continuing pilot tests for the “Energy Saving Process”, leading to the application of this new process in commercial CO 2 capture plant design. This paper introduces and presents the current status of the KEPCO & MHI CO 2 capture technology and concepts for future energy reduction improvements. The paper will also include test results in relation to newly developed absorbents, and the “New Energy Efficient Process”, which have enhanced the performance and reduced the associated energy penalty of the CO 2 capture process. KEPCO and MHI are continuing the development of efficient absorbents and optimized processes, thus helping to facilitate the future wide scale deployment of CO 2 capture technology as an effective counter measure against global warming.

The aim of this study was to examine enhancing effect of L: -histidine into cultured rat lung microvascular endothelial cells (LMECs), which constitute the gas-blood barrier. Uptake of L: -histidine into LMECs markedly increased with the addition of ZnSO(4) (0.1 mmol/L), and this enhanced uptake of L: -histidine was drastically reduced in the presence of the Na(+)-independent system L substrate, 2-amino-2-norbornanecarboxylic acid (BCH). However, the uptake of L: -histidine together with ZnSO(4) was not reduced by the addition of metabolic inhibitor, 2,4-dinitrophenol, or sodium ion replacement. Moreover, the addition of the system N-substrate, L: -glutamic acid γ-monohydroxamate did not significantly decrease the uptake of L: -histidine with 143 mmol/L Na (+) + 1 mmol/L BCH. These results indicated that system-N transporter does not play a role in the uptake of L: -histidine in the presence of ZnSO(4), suggesting that only system-L transporter is involved in the uptake of L: -histidine, although L: -histidine in the absence of ZnSO(4) was taken up by at least two pathways of Na(+)-dependent system-N and Na(+)-independent system-L processes into rat LMECs. The uptake of L: -histidine into rat LMECs in the presence of ZnSO(4) was also found to be unaffected by pH (5.0-7.4), indicating that uptake of L: -histidine into LMECs by the addition of zinc may not be involved in the H(+)-coupled transporters.

Cembrane-type diterpenoids, 13,18,20- epi - iso -chandonanthone ( 1 ) and (8 E )-4α-acetoxy-12α,13α-epoxycembra-1(15),8-diene ( 2 ), two fusicoccane-type diterpenoids, fusicoauritone 6α-methyl ether ( 3 ) and 6β,10β-epoxy-5β-hydroxyfusicocc-2-ene ( 4 ) and a zierane sesquiterpene γ-lactone, chandolide ( 5 ) were isolated from the Tahitian liverwort Chandonanthus hirtellus (Web.) Mitt., together with eight known diterpenoids, chandonanthine ( 6 ), fusicogigantone A ( 7 ), fusicogigantone B ( 8 ), fusicogigantepoxide ( 9 ), anadensin ( 10 ), fusicoauritone ( 11 ), ent -verticillol ( 12 ) and ent - epi -verticillol (13 ). Their structures were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analyses. Compounds 1 , 5 and 10 showed weak cytotoxic activity against HL-60. Compound 3 also indicated weak cytotoxic activity against KB cell lines.

A drimane, (+)-drimenol (1), five known herbertanes, (-)-alpha-herbertenol (2), (-)-herbertenediol (3), mastigophorene A (4), (-)-mastigophorene C (5) and (-)-mastigophorene D (6), a pimarane, (-)-ent-pimara-8(14),15-dien-19-oic acid (7), and two eudesmanolides, (-)-diplophyllolide A (8) and (-)-diplophyllin (9) were isolated from the Tahitian Mastigophora diclados (Brid.) Nees. Herbertane sesquiterpenes (2, 3, 5 and 6) showed cytotoxicity against HL-60 and KB cell lines, radical scavenging activity and antimicrobial activity against Bacillus subtilis. (-)-Diplophyllolide A (8) also exhibited cytotoxicity against HL-60 and KB cell lines.

The antioxidant activity of a provitamin C agent, 2-O-beta-D-glucopyranosyl-L-ascorbic acid (AA-2betaG), was compared to that of 2-O-alpha-D-glucopyranosyl-L-ascorbic acid (AA-2G) and ascorbic acid (AA) using four in vitro methods, 1,1-diphenyl-picrylhydrazyl (DPPH) radical-scavenging assay, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS(*+))-scavenging assay, oxygen radical absorbance capacity (ORAC) assay, and 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis inhibition assay. AA-2betaG slowly and continuously scavenged DPPH radicals and ABTS(*+) in roughly the same reaction profiles as AA-2G, whereas AA quenched these radicals immediately. In the ORAC assay and the hemolysis inhibition assay, AA-2betaG showed similar overall activities to AA-2G and to AA, although the reactivity of AA-2betaG against the peroxyl radical generated in both assays was lower than that of AA-2G and AA. These data indicate that AA-2betaG had roughly the same radical-scavenging properties as AA-2G, and a comprehensive in vitro antioxidant activity of AA-2betaG appeared to be comparable not only to that of AA-2G but also to that of AA.

The glutathione S-transferase (GST)-fused protein expression system has been extensively used to generate a large quantity of proteins and has served for functional analysis in vitro. In this study, we developed a novel approach for the efficient intracellular delivery of GST-fused proteins into living cells to expand their usefulness up to in vivo use. Since protein cationization techniques are powerful strategies for efficient intracellular uptake by adsorptive-mediated endocytosis, GST-fused proteins were cationized by forming a complex with a polycationic polyethylenimine (PEI)-glutathione conjugate. On screening of protein transduction, optimized PEI-glutathione conjugate for protein transduction was characterized by a partly oligomerized mixture of PEI with average molecular masses of 600 (PEI600) modified with multiple glutathiones, which could have sufficient avidity for GST. Furthermore, enhanced endosomal escape of transduced GST-fused proteins was observed when they were delivered with a glutathione-conjugated PEI600 derivative possessing a hydroxybutenyl moiety. These results were confirmed by both intracellular confocal imaging of GST-fused green fluorescent protein and activation of an endogenous growth signal transduction pathway by a GST-fused constitutively active mutant of a kinase protein. These PEI-glutathione conjugates seem to be convenient molecular tools for protein transduction of widely used GST-fused proteins.

火力発電所などの排ガス中からCO2を分離回収する技術として，従来の充填塔方式に代わり，中空糸膜を介した化学吸収法は装置をコンパクト化し，分離回収コストを削減できると期待されている．本研究ではPTFE, PPおよびPEの3種類の材質の中空糸膜について向流接触型のモジュールを用い，MEA水溶液を吸収液としてCO2/N2の模擬ガスからのCO2吸収実験を行い，膜の形状，物性が物質移動係数およびCO2吸収性能に及ぼす影響について検討を行った．またシミュレーションモデルを構築し，それらの影響を理論的に検討した．PEの延伸膜を除き，CO2回収率および総括物質移動係数の実験結果とシミュレーションによる計算結果の一致はおおむね良好であり，モデルの妥当性が確認された．PTFEは中空糸径，膜厚が他の材質のものに比べ大きく，その結果CO2回収率は最も低かった．PPおよびPEの中空糸膜は流速などを調整することにより80–90%の高いCO2吸収率を達成できた．しかし，PTFEでは膜の細孔径の増加に伴いCO2回収率は増加し，理論的にも裏づけられたが，PP, PEではその逆の依存性を示した．PEの延伸膜ではCO2回収率が著しく増大し，延伸処理が中空糸膜のCO2吸収性能を向上させる有効な手段であることが実証された．しかし，延伸による中空糸膜形状の変化，あるいは延伸により引き起こされうる細孔径，屈曲度の変化を考慮した計算からはそのような著しいCO2回収率の増大は説明することができず，本モデルでは考慮されていない現象が関与していることが示唆された．

An investigation of the edge region in a large reversed-field pinch (RFP) device has been undertaken for the first time using a high time resolution gas-puff imaging (GPI) system, applied to the TPE-RX experiment. The GPI diagnostic is aimed at the investigation of turbulence in the edge region under the severe heat flux conditions of thermonuclear fusion-grade plasmas, where conventional electrostatic probes cannot be used. To compare the data obtained by the GPI during low power experiments, a retractable array of electrostatic probes has been added. The whole diagnostic system provided high quality measurements of fluctuations with fine spatial and temporal resolution, as well as radial profiles of relevant plasma parameters. The measurements confirm several important properties of plasma edge already found in other experiments, like the presence of a strong ExB shear layer and the 'intermittent' behaviour of the measured quantities, which display non-Gaussian fluctuation spikes at different time scales. Along with the conventional power spectra and correlation analyses, the application of continuous wavelet transform techniques to GPI data allowed a detailed description of the spatial structure and of the propagation of these localized 'intermittent events'.

CO2化学吸収プラントのCO2回収熱量は吸収塔高さなど設備上の因子に加えて，化学吸収液のCO2解離熱，CO2ガスと吸収液の気液平衡特性，反応速度定数の3つの基礎特性に大きく依存することが知られている．しかし，新しい吸収液のプラント適用を考える場合に，この3特性は各々独立した性格を持つので，総合的な性能であるCO2回収熱量を予測することが困難であった．今回，CO2と液の反応熱，気液平衡デ－タからの実効CO2ロ－デングおよび反応速度定数からのCO2吸収率からCO2回収熱量を計算する数式を作成した．この方法でCO2回収熱量を計算した結果を関西電力（株）大阪南港排煙脱炭プラントの実績と対比したところ良好な対応を得た．このことから，提案した今回の計算方法を用いれば新吸収液の性能予測が可能であることが判明した．

主要なCO2化学吸収液6種の反応速度特性試験を温度298 Kで行った．実験は平面撹拌槽で実施され，気液の水平界面が完全に平滑であることを目視確認した．試験した吸収液は2-アミノ-2-メチル-1-プロパノール（AMP），KS-1液，モノエタノールアミン（MEA），メチルアミノエタノール（MAE），メチルジエタノールアミン（MDEA）およびジエタノールアミン（DEA）である．MAEとKS-1吸収液は反応速度特性が良く，これらのCO2吸収速度は従来の代表的吸収液であるMEAと比べて大きかった．また，反応速度定数を簡易に求める方法についても検討した．CO2とアミンの反応速度定数を求めるには，反応速度特性試験に加えて，物理吸収試験が必要である．この比較的困難な実験を行うことなく，計算で反応速度定数を求めることができた．このような計算は，分子量が60–120で，アミン濃度が1.4 kmol·m−3以下の希薄溶液について可能となる．MAEの反応速度定数は298 Kで7.99×103 m3·kmol·s−1, KS-1の反応速度定数は4.71×103 m3·kmol·s−1と算出され，MEAの反応速度定数（3.63×103 m3·kmol·s−1）より大きい結果が得られた．

Low-aspect-ratio reversed field pinch (RFP) plasmas are expected to produce equilibria in which the resonant surfaces for tearing modes are well separated compared with high-aspect-ratio RFP plasmas. The profile of the safety factor, q, determines the mode separation of the resonant surfaces. The q profiles, the ratio of plasma pressure to magnetic energy, β, and the parallel current density to the magnetic field lines, μ, are studied with the varying aspect ratio, A. A new Mercier stable RFP plasma is proposed by introducing a finite surface toroidal current density at the plasma edge. The aim of this study is to investigate the effect of a finite surface toroidal current with a low-aspect-ratio (low A) on the profiles of q, μ, β and the ratio of plasma pressure to poloidal magnetic energy, β p . The investigation is performed using an equilibrium model with a finite pressure, in which unknown functions in the Grad-Shafranov (GS) equation are specified. Specified functions are composed of some numerical parameters that allow systematic variation of equilibria. The GS equation is solved in the toroidal coordinate for various A values, where the β limit of Mercier stable equilibria is determined. First we confirmed that q at the centre, q 0 , increases as A decreases. The result shows that the profiles of q, β and β p , strongly depend on A. The β and β p obtained decrease with decreasing A. In particular, the decrease in β differs from the case of a tokamak. The decrease in β is recovered, in spite of a low A, by setting the toroidal current to be finite at the plasma edge as a boundary condition.

In order to reduce the thermal wall load due to the phase- and wall-locked modes particularly in the high plasma current regime, neutral gas puffing experiments have been conducted in the TPE-RX reversed-field pinch. The temperature of the plasma-facing wall at the mode-locking position sometimes exceeds the melting temperature of stainless steel. It has been determined that the maximum temperature increment of the wall becomes almost half in the neon and deuterium gas puffing cases at a plasma current of 350 kA. This indicates that neutral gas puffing can reduce the severe thermal wall load. The radiative cooling around the peripheral region as a result of neon gas puffing and the decrease in the heat flux along local magnetic field lines as a result of deuterium gas puffing are possible reasons behind the decrease in the rate of energy flow to the wall.

A database of the confinement properties of the toroidal pinch experiment (TPE) series reversed-field pinch (RFP) devices was established, and an empirical scaling law for the energy confinement time, τE, was deduced for a consistently selected set of the database (Yagi Y. et al 2003 Nucl. Fusion 43 1787). The scaling for τE [TPE-scaling; ], in particular, is a power law similar to that predicted on the basis of the tearing modes, as a function of the plasma minor radius (a), plasma current (Ip), and Ip/N, where N is the column density. On the other hand, the TPE-scaling has a strong dependence on the pinch parameter, Θ, namely τE ~ Θ3. Recently, we have investigated the database of the improved confinement in the pulsed poloidal current drive (PPCD). We show that the TPE-scaling agrees well with the improved τE in the PPCD database, because of its strong Θ dependence. Namely, Θ3 is a factor of merit for RFP plasmas. We discuss why this agreement is obtained in spite of the general difference between the underlying transport mechanisms of the standard and PPCD discharges. We also show that this improvement, represented by Θ3, is related to the increase in magnetic shear with Θ.

According to a simplified costing algorithm for a steady-state fusion reactor power plant, the relative attractiveness of advanced physics modes mainly depends on the stability and noninductive current drive of the equilibrium. The high-stability beta and the good alignment of the equilibrium current profile with a self-induced plasma current profile are compatible with the low-aspect-ratio neoclassical Reversed-Field-Pinch equilibrium solved self-consistently considering the self-induced plasma current. The high-stability beta is due to the hollow current profile making the magnetic shear increase and the force-free field dominant. The good alignment of the current profile significantly reduces the power required for noninductive current drive to generate the steady-state magnetic field configuration. As a result, the fusion power plant based on the neoclassical RFP equilibrium with low aspect ratio enables electricity to be generated at relatively low cost.

気液平衡試験装置（容積1 L）を試作し，主要なCO2吸収液5種の気液平衡特性試験を行った．試験した吸収液は2-アミノ-2-メチル-1-プロパノール（AMP），KS-1液，モノエタノールアミン（MEA），メチルアミノエタノール（MAE）およびジエタノールアミン（DEA）である．AMPとKS-1液がCO2に対して優れた気液平衡特性を示した．すなわち，両者はCO2吸収量が0.76–0.80 mol CO2/mol amineと大きく，かつ高温側で0.16–0.23 mol CO2/mol amineと再生しやすい性質がある．次に，CO2分離回収装置の吸収条件と再生条件における各々の吸収液のCO2ローディングから，前者と後者のCO2ローディングの差を実効CO2ローディングと定義した．この実効CO2ローディングは，CO2分離回収プロセスにおける正味の吸収性能を決める重要な指標となることがAMPとKS-1液の結果から判明した．

In addition to regulation of normal cell functions, hepatocyte growth factor (HGF) has also been shown to be involved in malignant cell transformation and in growth, invasion and metastasis in cancer cells. Inhibitors of HGF production have a potential for interfering with malignant cell transformation and progression of tumors. We found that tryptanthrin, one of the major compounds extracted from the medicinal plant Polygonum tinctorium, which is known for its antitumor activity, strongly inhibited HGF production stimulated by various HGF inducers in human dermal fibroblasts. HGF production induced by phorbol 12-myristate 13-acetate (PMA) was potently inhibited by tryptanthrin without any appreciable cytotoxic effect. Tryptanthrin also inhibited HGF production induced by epidermal growth factor (EGF) and platelet-derived growth factor. Moreover, proliferation of the fibroblasts induced by the two growth factors was potently suppressed by tryptanthrin to the level of proliferation of unstimulated fibroblasts. However, tryptanthrin did not inhibit HGF production induced by the protein kinase A-activating agents cholera toxin and 8-bromo-cAMP. These effects of tryptanthrin were different from the effects of transforming growth factor beta1 and dexamethasone, both of which inhibit HGF production induced by all the above inducers. Upregulations of HGF gene expression by PMA and EGF were also inhibited by tryptanthrin. Activation of the mitogen-activated protein kinase (MAPK) signaling pathway is crucial for PMA-induced HGF production, but tryptanthrin did not attenuate phosphorylation of MAPK induced by PMA. These results indicate that tryptanthrin potently inhibited induction of HGF production probably through events downstream of MAPK activation.

We report that the thermal wall load due to locked modes can be decreased by means of gas puffing in the reversed-field pinch (RFP) device, TPE-RX [Y. Yagi et al.: Fus. Eng. Design 45 (1999) 409]. Under standard RFP operation in TPE-RX, the phase- and wall-locked modes, i.e., spatially localized and stationary magnetic perturbations, respectively, appear after the current-rising phase. The locked modes cause a severe thermal wall load of the order of 100 MW/m2 on the first wall. It is estimated that the temperature on the plasma-facing wall at the mode-locking position sometimes exceeds the melting temperature of stainless steel. The thermal wall load increases with plasma current, Ip. We have succeeded in mitigating the high thermal wall load by gas puffing during discharges. It is shown that the maximum temperature increment of the vacuum vessel wall is halved when a gas-puffing rate of 200 Pa m3/s is applied at Ip=350 kA. The characteristics of the temperature increase of the vacuum vessel are presented, and they indicate the nature of the locked mode in RFP discharges in TPE-RX.

The application of the pulsed poloidal current drive (PPCD) technique in reversed-field pinch (RFP) devices leads to the improvement of the confinement properties of the plasma. In this article the conditions necessary to achieve high PPCD performance in the TPE-RX [Y. Yagi, S. Sekine, H. Sakakita et al., Fus. Eng. Des. 45, 409 (1999)] RFP device will be shown. One of the key parameters is the component of the electric field parallel to the magnetic field E∥. The positive trend between E∥ and the PPCD performance can be explained in terms of reduction of magnetic fluctuations. It will also be shown that important roles are played by the triggering time of the PPCD pulses, the filling pressure of the deuterium gas, and the wall condition.

Recent progress in the physics and engineering design study for the modification programme of JT-60 is presented. In order to achieve a steady state high-β plasma operation, which is the dominant issue of this programme, physics design for the MHD control and the stability analysis is investigated. Engineering design and the R & D for the superconducting coils, irradiation shield are performed well towards the mission of programme.

高さ約25mのパイロットスケールの吸収塔を用いて排ガス量を定格の555m3/hから約2倍の1100m3/hの範囲まで増加させて, 火力発電所排ガスに対する炭酸ガスの分離・回収を行った.この結果から, アルカノールアミン系ヒンダードアミンである吸収剤KS-1を用いた化学吸収法でかつ吸収塔の充てん材に規則充てん材を装着することにより, 炭酸ガス回収量を従来の設計の約2倍に増加できた. 言い換えれば, 従来の1/2の断面積の吸収塔で同一量の排ガスが処理できることになり, 吸収塔建設コストを大幅に削減できることになる.

A confinement database of the reversed-field pinch (RFP) devices of the toroidal pinch experiment (TPE) series has been established. The TPE database contains global confinement properties under various experimental conditions for four different devices and seven different cases, which cover two decades of experiments. Characteristics of the TPE database have been extracted under consistent experimental conditions of conventional RFP discharges, and scaling laws of the poloidal beta, ?p and energy confinement time, ? E, are given against independent parameters that include the size of the plasma and the pinch parameter ?. Scaling laws of and are obtained for a set of scans, where a is the plasma minor radius, Ip the plasma current and N the column density. The scaling of ? E on a, Ip, and I/N is similar to that dominated by the transport under tearing instability. Another scaling shows that ? E is inversely proportional to the Joule input power. The scaling for the apparent effective charge shows a positive correlation both with Ip and I/N.

The locked mode (LM), which is locked both in phase and to the wall, is successfully controlled using a rotating toroidal field (RTF) in TPE-RX (large reversed-field pinch machine with R/a = 1.72 m/0.45 m and plasma current Ip up to 480 kA) at a low Ip (~200 kA) and high filling pressure (~0.8 mTorr). It is demonstrated that the onset of the LM can be delayed or even eliminated by applying the RTF. Only the Fourier component with m=0/n=1 of the magnetic fluctuation exhibits rotation with the RTF, but other modes do not exhibit systematic movement synchronizing with the m=0/n=1 mode rotation. The phase relation between the m=0/n=1 mode and the other modes becomes random, which probably prevents the phases of the other modes from locking and results in the elimination of the LM. It is found, however, after the LM has taken place, it cannot be controlled by the RTF and hence an early start and fast rotation of the RTF are required for control. It is not possible to control the LM at a high Ip (\gtrsim250 kA), since the LM takes place from the early stage of discharge. Compared with discharges without the LM, plasma performance is degraded by the LM. The performance can be recovered by eliminating the LM with the RTF. However, the RTF itself degrades the plasma performance when applied to LM-free discharges with a RTF value comparable to that necessary for controlling the LM.

A fully superconducting tokamak named JT-60SC is designed for the modification programme of JT-60 to enhance economical and environmental attractiveness in tokamak fusion reactors. JT-60SC aims at realizing high-β steady-state operation in the use of low radio-activation ferritic steel in a low ν* and ρ* regime relevant to the reactor plasmas. Objectives, research issues, plasma control schemes and a conceptual design for JT-60SC are presented.

The pulsed poloidal current drive (PPCD) [J. S. Sarff et al., Phys. Rev. Lett. 72, 3670 (1994)] experiment is conducted in a reversed-field pinch device, the toroidal pinch experiment RX (TPE-RX) after providing an auxiliary power supply system with increased energy in the main power supply system for the PPCD. The PPCD system thus provides double-pulsed operation with higher current in the toroidal coil than that in single-pulsed PPCD operation in TPE-RX [Y. Yagi et al., Plasma Phys. Controlled Fusion 44, 335 (2002)]. The central electron temperature, ion temperature, and electron density increase during PPCD, and there is, on average, a fivefold improvement in energy confinement, τE, relative to standard discharges. Double-pulsed PPCD yields better performance than that of single-pulsed PPCD operation where twofold improvement in τE was obtained. It is shown that the enhancement factor of τE in the double-pulsed PPCD experiment in TPE-RX is consistent with the trends, observed previously, versus magneti...

A spectroscopic system equipped with image magnifying optics has been developed for measuring a time-resolved plasma velocity at one discharge of a reversed-field-pinch plasma of the TPE-RX at National Institute of AIST. This spectroscopic system enables a simultaneous measurement from two different lines of sight, using two sets of quartz optical fiber bundles. This system provides a precise measurement of Doppler shift without the need for a calibration of the central location of a spectral line. Two fiber bundles are coupled to the entrance slit of a modified Czerny–Turner-type, 1-m-focal-length spectrometer with an 82×82 mm2 grating. In order to adjust the spectral image of the exit slit to each surface of two sets of one-dimensional detector arrays, an optical system equipped with a toroidal mirror, a cylindrical mirror, and splitting mirrors has been developed. The focal lengths of the toroidal mirror are selected for focusing vertically on the splitting mirror and horizontally (wavelength direction) on detectors. Plasma rotation and ion temperature for O V impurity ions (278.1 nm) are successfully measured at one plasma shot with a 25-μs time resolution in the TPE-RX.

An overview of the present diagnostics system for a reversed-field pinch machine, the toroidal pinch experiment RX [TPE-RX, R/a=1.72/0.45 m, Ip

Data acquisition and analysis systems for a reversed-field pinch (RFP) machine, the toroidal pinch experiment (RX) [TPE-RX, R/a=1.72/0.45 m, Ip

Pulsed poloidal current drive (PPCD) (Sarff J S et al 1994 Phys. Rev. Lett. 72 3670) is conducted in a reversed-field pinch (RFP) machine, TPE-RX. The PPCD yields a twofold improvement of poloidal beta and energy confinement time. A quiescent phase is observed in the magnetic fluctuations, δb, during the PPCD. The result is discussed in terms of the change of the equilibrium configuration along the F-Θ trajectory (F and Θ are the reversal and pinch parameters, respectively). Representative mode amplitude is numerically simulated. The result indicates that a transient nature of the PPCD, where τPPCD (characteristic time of the PPCD operation) <

One of the hypotheses for the cause of the locked mode in reversed-field pinch (RFP) plasmas is examined using a large RFP machine, TPE-RX. A hypothetical model was proposed [Phys. Plasmas 6 (1999) 3824], which speculates that the halo current in the vacuum vessel might be the cause of the locked mode. We directly measured the toroidal distribution of the vessel current and correlated it with the position and the magnitude of the locked mode. The vessel current is found to flow into the contact point of the last closed flux surface where the locked mode exists. Magnitude of the vessel current is much smaller than the level expected to form the locked mode. From these observations, we conclude that this vessel current is a result of the local shift of the plasma column due to the locked mode, and may not be the cause of the locked mode.

To find new metabolites similar to cotylenins and fusicoccins from the fungus Alternaria brassicicola, screening tests were carried out using the lettuce seed dormancy breaking assay. Activity-guided fractionation of the EtOAc extract from the culture using the assay afforded the isolation of two novel fusicoccane diterpenoids named brassicicenes J (1) and K (2), along with three known brassicicenes A (3), B (4), and F (5). Their structures were elucidated from extensive NMR spectral data and by comparison of these with those reported in the literature. Brassicicenes (1–5) exhibited weak to moderate seed dormancy breaking activities against lettuce seeds in the presence of abscisic acid. In addition, the necrotic/apoptotic activities of the brassicicenes (1–5), fusicoccin A (6) and cotylenin A (7) were evaluated by determining their cytotoxicity, cell viability and caspase-3/7 activation on the HL-60 cell line. Brassicicene K (2) exhibited similar cytostatic profiles to that of cotylenin A (7), and brassicicenes J (1), A (3), B (4), and F (5) exhibited necrotic activity. This is the first report of the seed dormancy breaking activity of brassicicenes in plants, and of necrotic/apoptotic activity in mammalian cells.

Neutron diffraction measurements were carried out for CO2-absorbed aqueous 11 mol % 2-aminoethanol (MEA) D2O solutions (corresponding to 30 wt % MEA solution) in order to obtain information on both the intramolecular structure and intermolecular hydration structure of the MEA carbamate molecule in the aqueous solution. Neutron scattering cross sections observed for (MEA)0.11(D2O)0.89, (MEA)0.11(D2O)0.89(CO2)0.06, and (MEA)0.11(D2O)0.89(DCl)0.11 solutions with different (14)N/(15)N ratios were used to derive the first-order difference function, ΔN(Q), which involves environmental structural information around the nitrogen atom of the MEA molecule. Intramolecular geometry and intermolecular hydration structure of MEA, protonated MEA (MEAD(+)), and MEA carbamate (MEA-CO2) molecules were obtained through the least-squares fitting of the observed Δ(N)(Q) in the high-Q region and the intermolecular difference function, Δ(N)(inter)(Q), respectively. In the aqueous solution, the MEA molecule takes the gauche conformation (dihedral angle, ∠NCCO = 45 ± 3°), suggesting that an intramolecular hydrogen bond is formed. On the other hand, values of the dihedral angle ∠NCCO determined for MEAD(+) and MEA-CO2 molecules were 193 ± 4° and 214 ± 8°, respectively. These results imply that the intermolecular hydrogen bonds are dominated for MEAD(+) and MEA-CO2 molecules. The intermolecular nearest neighbor N···O(D2O) distance for the MEA molecule was determined to be 3.13 ± 0.01 Å, which suggests weak intermolecular interaction between the amino-nitrogen atom of MEA and water molecules in the first hydration shell. The nearest-neighbor N···O(D2O) distances for MEAD(+) and MEA-CO2 molecules, 2.79 ± 0.03 and 2.87 ± 0.04 Å, clearly indicate strong hydrogen bonds are formed among the amino group of these molecules and neighboring water molecules.

Wall-locking and phase-locking modes are studied in detail in a reversed-field pinch device, TPE-RX [Y. Yagi et al., Fusion Eng. Design 45, 409 (1999)]. These mode-locking phenomena arise from tearing instabilities. Wall locking means the stopping of mode rotations, and phase locking means the locking of the phases of multiple modes. Phase locking induces a toroidally localized enhanced magnetic amplitude. There are two types of mode-locking states in TPE-RX. One of them exhibits a clear phase-locked structure, while the other exhibits a weak toroidal localization. Both types show finite toroidal rotation during the current-rising phase of the discharge, and are eventually wall locked during the current flat-top phase. However, the rotation speeds are clearly different between the two types. Confinement properties are compared between the two types of mode-locking states. It is shown that the threshold for the mode amplitude necessary to wall lock the toroidal rotation, as well as the bifurcation of phase...

Spatially localized heat flux due to the locked mode in a reversed-field pinch device, TPE-RX, is investigated by using a multipoint vessel temperature monitoring system (VTMS) which has 268 thermocouples distributed on the outer surface of the vessel system. It is shown by two-dimensional mapping that the locally enhanced thermal wall load correlates closely with the mode locking positions. Heat flux shows spatial peaks (full width at half maximum) of ∼10° and ∼100° in the toroidal and poloidal directions, respectively. Typical heat flux at the locked position is estimated to be of the order of 100 MW/m2, and the increment of the vessel temperature on the plasma side-surface exceeds 1000° with 0.35 MA plasma current.

A design and related studies of equilibrium field control coil system of TPE-RX reversed field pinch (RFP) machine are described. Here the equilibrium field control coil system stands for the coils to produce poloidal magnetic field necessary for the plasma equilibrium condition. The configuration and the number of turns of the equilibrium field control coil system were designed so as to minimize the field error for reducing the plasma–wall interaction, especially at the shell gap of the thick metal shell. The design method of the equilibrium field control coil system taking account of an iron core with two yokes and the thick metal shell with the poloidal shell gap is described. As a result of the design of the equilibrium field control coil system, field error at the plasma surface is less than 1.0%. The field error can be canceled for wide range of the plasma equilibrium condition by adding the compensatory vertical field. Construction of TPE-RX was successfully completed at the end of 1997 and the coil system showed the expected performances.