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Generalized scaling laws for the formation of plasma confining potentials are investigated to find the physics essentials common to representative tandem-mirror operational modes in GAMMA 10. These modes are characterized in terms of (i) a high-potential mode and (ii) a hot-ion mode. The potential-formation scalings in these modes are consolidated and generalized on the basis of the consistency with finding of the wider validity of Cohen’s strong electron-cyclotron heating (ECH) theory covering over both modes. A plateau-shaped electron distribution function is observed when a plug electron-confining potential is formed in the hot ion mode of GAMMA 10, as predicted in terms of the strong ECH theory.

Following the 2002 Conference on Open Magnetic Systems for Plasma Confinement, a three times progress in the formation of ion-confining potential height is achieved in the hot-ion mode. The advance in the potential formation leads to a finding of remarkable effects of radially produced shear of electric fields dEr/dr on the suppression of not only coherent drift waves but turbulence-like fluctuations for the first time in GAMMA 10. Also, the progress in the potential formation is made in line with the extension of our proposed physics scaling of potential formation covering over representative tandem-mirror operational modes, characterized in terms of (a) a high-potential mode having kV-order plasmaconfining potentials and (b) a hot-ion mode yielding fusion neutrons with 10-20 keV bulk-ion temperatures (Ti).

Abstract: As part of a series of physical modeling studies on the electrochemical etching of a printed wiring board, copper foil was anodically dissolved in a small cavity. Coupling of the ionic mass transfer rate with the undercutting phenomena must be precisely understood in order to finely control high aspect ratio anisotropic etching. Interferometry has been applied to the study of the ionic mass transfer rate accompanying electrochemical reactions, and it may help in the visualization of the concentration profile of the metal ion within a narrow cavity. As an idealistic case, the electrochemical dissolution of copper in a purely diffusional field, especially the Cu2+ ion transfer rate itself, is now the focus of attention. The copper anode was galvanostatically dissolved in an aqueous solution (0.1M CuSO4-1M H2SO4) contained in a quasi-two-dimensional electrolytic cell for 8 seconds during free fall in a drop shaft. A disk type of anode, 1 mm in diameter and 100 m in thickness, and a flat shaped ring cathode 20 mm in inner diameter were sandwiched by two sheets of slide glass. The electrolyte layer was 200 m in effective thickness. The interference fringe pattern accompanying the copper dissolution was measured in situ with a common path-type microscopic laser interferometer. Terrestrial experiments were also conducted with a horizontally installed cell under the same electrolytic conditions. No natural convection would be expected in the present electrolytic cell design with such a shallow and horizontal electrolyte layer. The distance between the anode surface and the location at which the outer interference fringe appeared was measured by the duration time. It increased linearly with the square root of time under microgravity, but started to deviate from this linearity a few seconds after starting the electrolysis in the terrestrial experiment. A significant difference in the growing distance between the environments had not been a priori anticipated for such a quasi-two-dimensional cell. The local current density distribution along the smaller electrode surface may be influenced by induction of a kind of natural convection.

Single crystal stishovite with a square prismatic habit and maximum length 0.8 mm was grown from a-quartz at 120 kbar and ~1,300° C. Li2WO4, chosen as a result of a previous experiment in growing coesite, was also successful as flux for stishovite. Single crystal X-ray structure analysis of the crystals thus obtained has been carried out at high temperatures under ambient pressure. Lattice constant measurements give a larger thermal expansion coefficient along the a-axis than along the c-axis. The bond distances and bond angles show a decreasing distortion of the SiO6 octahedron with increasing temperature. The increasing amplitude of thermal vibrations of oxygen atoms with increasing temperature results in increasing O-O repulsion in the basal plane, which explains the observed crystallographic changes.

NM441 is a lipophilic prodrug of a new thiazeto-quinoline carboxylic acid derivative NM394, and when it is administered orally it is readily absorbed and hydrolyzed to its parent compound. After oral administration of NM441 at a dose of 20 mg/kg to dogs, the peak concentration of NM394 in plasma was 2.39 micrograms/ml, whereas it was 0.63 micrograms/ml for NM394 administered alone. The in vivo activity of NM441 was compared with those of ciprofloxacin, ofloxacin, and enoxacin in mouse protection studies. NM441 was as effective as ofloxacin and was twice as effective as ciprofloxacin against systemic infection with Staphylococcus aureus. Against infections with streptococci, NM441 was two to three times as effective as ofloxacin and five times as effective as ciprofloxacin. Against infection with Escherichia coli, NM441 was as effective as ciprofloxacin and ofloxacin, but against infections with Klebsiella pneumoniae, Serratia marcescens, and Pseudomonas aeruginosa, NM441 was two to four times as effective as ciprofloxacin and ofloxacin. NM441 was three to seven times as effective as enoxacin in systemic infections. Against urinary tract infections with E. coli, NM441 reduced the number of bacterial CFU per gram of kidney by 1 to 2 log10 more and, with P. aeruginosa, by 1 to 6 log10 more than did ciprofloxacin and ofloxacin. Against respiratory tract infections with K. pneumoniae, NM441 was as effective as ofloxacin and was twice as effective as ciprofloxacin.

NM394 is a new 6-fluoroquinolone antibacterial agent with a tricyclic structure which has a bridge that connects the N-1 and C-2 positions of the quinolone. The antibacterial activity of NM394 against clinical isolates of staphylococci, streptococci, enterococci, members of the family Enterobacteriaceae, and Pseudomonas aeruginosa was equal to or one-half that of ciprofloxacin. NM394 was as active as ofloxacin against gram-positive bacteria and was two to eight times more active against gram-negative bacteria, including P. aeruginosa. NM394 was two to eight times more active than enoxacin against gram-positive and gram-negative bacteria. The MICs of NM394 against Escherichia coli and P. aeruginosa at pH 5.5 were reduced 4 to 16 times compared with those at pH 7.0. Ciprofloxacin, ofloxacin, and enoxacin were 2 to 32 times less active against these two bacteria and Staphylococcus aureus at an acidic pH than they were at pH 7.0. In the presence of 5 mM Mg2+, the MICs of all of these drugs increased 2 to 32 times, but they were only slightly affected by 5 mM Ca2+, type of medium, serum, or size of inoculum. NM394 showed potent bactericidal activity and inhibited the supercoiling activity of E. coli DNA gyrase. The in vitro antibacterial profile of NM394 is similar to that of other 6-fluoroquinolones.

Abstract: The plasma nitriding behaviour of Fe-18Cr-9Ni alloy was compared with gas nitriding. The alloy was nitrided under the following conditions: specimen temperature: 823 K, nitriding time: mainly 108 ks, total pressure: 0.4–0.7 kPa, mixture ratio of N2 and H2∶ 0.25, discharge voltage: 350–450 V, current: 0.8–1.1 A. Formation of a surface layer of iron nitrides was not observed. Formation of a homogeneous internal nitriding layer, consisting of small precipitates of CrN and the γ-phase matrix, was, however, noted. The lattice constant at the specimen surface was smaller than that at greater depth. This may have been because the sputtering effect decreased the dissolved nitrogen content at the specimen surface. The sputtering of iron nitrides at the specimen surface by the plasma was experimentally confirmed through γ′-Fe4N formation on Si beside an alloy specimen. The characteristics of the plasma nitriding mentioned above are discussed in relation to the sputtering.

The uptake of NM394, a new quinolone, by and its subsequent elution from human polymorphonuclear leukocytes were studied and compared with those of ofloxacin and ciprofloxacin. The kinetics of the uptake of NM394 was similar to that of ciprofloxacin. The maximum intracellular-to-extracellular concentration ratio was 12.3, compared with 8.6 for ciprofloxacin and 4.9 for ofloxacin at the extracellular concentration of 20 micrograms/ml. The elution of NM394 from human polymorphonuclear leukocytes occurs relatively slowly; 5 min after the removal of extracellular NM394, nearly 100% still remained in polymorphonuclear leukocytes, compared with ofloxacin, which was so rapidly eluted that only 12% remained. The uptake of NM394 was significantly decreased at 4 degrees C and by the presence of NaCN but was not affected by the presence of L-glycine, L-leucine, L-serine, adenosine, or NaF. NM394 showed intracellular activity at a concentration of 0.1 microgram/ml that significantly reduced the number of phagocytosed Pseudomonas aeruginosa cells with 2 h of incubation. These results suggest that uptake of NM394 by human polymorphonuclear leukocytes occurs via an active transport system differing from that of ofloxacin, whose uptake is affected by the presence of L-glycine and L-leucine, and that once accumulated, NM394 remains intracellularly active and participates in protection against bacterial infection.

In order to clarify the effects of fusion-produced neutron irradiation on silicon semiconductor x-ray detectors, the x-ray energy responses of both n- and p-type silicon tomography detectors used in the Joint European Torus (JET) tokamak (n-type) and the GAMMA 10 tandem mirror (p-type) are studied using synchrotron radiation at the Photon Factory of the National Laboratory for High Energy Accelerator Research Organization (KEK). The fusion neutronics source (FNS) of Japan Atomic Energy Research Institute (JAERI) is employed as well-calibrated D-T neutron source with fluences from 1013to 1015neutrons/cm2onto these semiconductor detectors. Different fluence dependence is found between these two types of detectors; that is, (i) for the n-type detector, the recovery of the degraded response is found after the neutron exposure beyond around 1013neutrons/cm2onto the detector. A further finding is followed as a “re-degradation” by a neutron irradiation level over about 1014neutrons/cm2. On the other hand, (ii) the energy response of the p-type detector shows only a gradual decrease with increasing neutron fluences. These properties are interpreted by our proposed theory on semiconductor x-ray responses in terms of the effects of neutrons on the effective doping concentration and the diffusion length of a semiconductor detector.

Significant effects of sheared transverse electric fields in plasmas on both turbulent fluctuations and drift waves are experimentally demonstrated with improvement in plasma confinement for the first time in the tandem mirror GAMMA 10. Here, electron-cyclotron heatings (ECH) for ion-confining potential formation are applied in association with a significant rise in the absolute value of the central-cell potential and the resulting formation of a strong shear of electric fields of the order of 10 kV/m2 in the radial direction of the plasma column (dEr/dr). The central-cell line density increases during ECH in association with decreasing fluctuations. Various fluctuation diagnostics, in particular, the frequency analyses of end-loss ion currents and central soft x-ray brightness, show the consistent features. This encourages the usefulness of potentials and radial electric-field shear for confinement improvements.

The aminouracils (I) are consecutively heated and photolyzed with methyl propiolate (II) to form moderate yields of the title compounds (III) and the pyrimidylacrylates (IV), together with the benzenetricarboxylate (V).

The 1,3‐dialkyl‐6‐(alkylamino)uracils (I) react with dimethyl acetylenedicarboxylate (II) to form the adducts (III) and the ring closure products (IV).

Cyclization of the aminomercaptouracil (III), obtained from the diaminouracil (I) and hydrogen sulfide (II), with acetic anhydride (IV) leads to the formation of the thiazolo(5,4‐d)pyrimidinedione (V).