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A kinematically complete quasifree (p,pn) experiment in inverse kinematics was performed to study the structure of the Borromean nucleus ^{17}B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for 1s_{1/2} and 0d_{5/2} orbitals, and a surprisingly small percentage of 9(2)% was determined for 1s_{1/2}. Our finding of such a small 1s_{1/2} component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in ^{17}B. The present work gives the smallest s- or p-orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of s or p orbitals is not a prerequisite for the occurrence of a neutron halo.

A kinematically complete quasi-free $(p,pn)$ experiment in inverse kinematics was performed to study the structure of the Borromean nucleus $^{17}$B, which had long been considered to have neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for $1s_{1/2}$ and $0d_{5/2}$ orbitals, and a surprisingly small percentage of 9(2)$\%$ was determined for $1s_{1/2}$. Our finding of such a small $1s_{1/2}$ component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in $^{17}$B. The present work gives the smallest $s$- or $p$-orbital component among known nuclei exhibiting halo features, and implies that the dominant occupation of $s$ or $p$ orbitals is not a prerequisite for the occurrence of neutron halo., Accepted for publication in Physical Review Letters,8 pages, 4 figures

The formation of a dineutron in the nucleus $^{11}$Li is found to be localized to the surface region. The experiment measured the intrinsic momentum of the struck neutron in $^{11}$Li via the $(p,pn)$ knockout reaction at 246 MeV/nucleon. The correlation angle between the two neutrons is, for the first time, measured as a function of the intrinsic neutron momentum. A comparison with reaction calculations reveals the localization of the dineutron at $r\sim3.6$ fm. The results also support the density dependence of dineutron formation as deduced from Hartree-Fock-Bogoliubov calculations for nuclear matter.

Spectroscopy of 16B plays an essential role in understanding the halo structure in 17B, but very limited knowledge has so far been obtained. We have carried out a kinematically complete measurement on the spectroscopy of 16B by using quasi-free (p,pn) reaction on 17B. The level scheme of 16B up to 5 MeV was made clear for the first time.

We present an investigation of the structure of 13Be obtained via a kinematically complete measurement of the (p,pn) reaction in inverse kinematics at 265 MeV/nucleon. The relative energy spectrum of 13Be is compared to Transfer-to-the-Continuum calculations which use as structure inputs the overlaps of the 14Be ground-state wave function, computed in a three-body model, with the unbound states of the 13Be residual nucleus. The key role of neutron p-wave orbital in the interpretation of the low-relative-energy part of the spectrum is discussed. Keywords: Quasi-free scattering, Borromean nuclei, Three-body model, Resonances

International audience; Dineutron decay is a forefront topic in nuclear structure that still lacks a firm experimental claim. The spontaneous emission of a dineutron should be favored in nuclei that are unbound with respect to two-neutron emission but bound with respect to single-neutron emission. A very interesting candidate can be found by adding two neutrons to the most neutron-rich Beryllium isotope,$^{14}$Be, a well-known 2n-halo nucleus. The intriguing nature of the phenomenon has motivated recent theoretical calculations and a new experimental campaign at RIKEN RIBF. In this work, the decay properties of$^{16}$Be and the structure of$^{15}$Be have been probed via the proton-knockout reaction from a$^{17}$B beam.

The gradual erasing operation from reset state to set state adjusting pulse amplitude, duration time and falling time respectively in phase change device using Ge1Cu2Te3 is investigated. For this procedure, a relatively high voltage and increased falling time, which was able to produce both long-term potential and long-term depression in the time interval between pre-spike and post-spike is choosing. The results suggested that the presence of synaptic behaviour was due to controlled falling time rather than pulse amplitude.

We have measured a complete set of deuteron analyzing powers in deuteron–proton elastic scattering at 190, 250, and 294 MeV/nucleon. The obtained data are compared with the Faddeev calculations based on the modern nucleon–nucleon forces together with the Tucson-Melbourne’99, and UrbanaIX three nucleon forces. The data are also presented with the calculations based on the N4LO NN potentials of the chiral effective field theory.

Behçet's disease (BD) is a chronic inflammatory disease characterized by oral aphthous ulcers, genital ulcers, uveitis and skin lesions. Etiology and pathogenesis of BD are not fully elucidated, but the association with human leukocyte antigen (HLA)-B51 or B*5101 has been repeatedly reported. Previous studies have shown that there are few sequence variations in the protein-coding region of B51, while there is a report on many variations in the 5'-flanking region and intron. In this study, HLA-B*5101 gene from 37 individuals including Japanese, Turkish, Jordanian and Iranian patients and healthy controls were fully sequenced to further clarify the B*5101 gene in association with BD. We found that all the patients and healthy controls carried B*510101 with no variation in the 5'-flanking region, exon and intron. However, seven polymorphisms were found in the 3'-flanking region. These polymorphisms composed of six haplotypes that were shared and stretched over the ethnic groups, suggesting that the susceptibility to BD was conferred by the B*510101 itself and not by any genes in linkage disequilibrium with B*510101. In addition, phylogenetic analyses of B*510101 showed that the 3'-flanking sequences followed an evolutional divergence differently from that of the other regions, implying that a unifying selection might operate to conserve B*510101.

An electrostatically-tunable infrared filter was fabricated by constructing a Fabry–Perot interferometer with stacked silicon plates. Driving-voltage, which used to be ∼100 V with ordinary silicon plates, could be reduced to ∼30 V by decreasing plate thickness to 100 μm. Both theoretical simulation and bending test confirmed sufficient mechanical durability of these thin plates. Superimposition of a noise spectrum, which was caused by interference inside thin silicon plates, could be suppressed by polishing the plates into wedges. Consequently, pronounced interference peaks appeared at 12.6, 6.3, and 4.2 μm wavelengths, and they shifted to 9.8, 4.9, and 3.3 μm, respectively, by 30-V application.

A study of the healing of interfacial debonding in fibre-reinforced polymers (FRPs) was performed. In the composite, a microencapsulated healing agent and a solid chemical catalyst are dispersed within the coating layer on the surface of the fibres. Healing is triggered by crack propagation through the microcapsules, which then release the healing agent into the crack plane. Subsequent exposure of the healing agent to the chemical catalyst initiates polymerisation and bonding of the crack faces. Self-healing is demonstrated on flat tensile specimens of neat epoxy (no fibres) and unidirectional FRPs. The ratio of tensile strengths of the virgin and healed materials is used to quantitatively measure crack healing.

The high-performance liquid chromatographic separation of enantiomers of N-protected non-protein amino acid esters was investigated by using a cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phase column (Daicel Chiracel OD). The effect of the N-protecting groups and the ester groups on chiral discrimination was examined. The benzyloxycarbonyl (Z), 4-methoxybenzyloxycarbonyl, and 9-fluorenylmethoxycarbonyl derivatives gave good enantiomeric separations, while the formyl and t-butoxycarbonyl groups marred them. Almost all the alkyl esters examined and the benzyl ester gave enantiomeric separations better than or of the same order as the methyl ester. The N-Z-protected methyl esters of a number of non-protein α-amino acids were well resolved using hexane–2-propanol as a mobile phase. The resolution of β-amino acid derivatives was inferior to that of the isomeric α-amino acid derivatives.

Raising organic loading rate, and the behavior of dissolved CODcr (D-CODcr), VFA and specific methanogen activity, were investigated through a laboratory experiment for the start-up of a sludge recycling center. Moreover, application for MPN-PCR methods using a gene as a direct technique to measure the quantity of methanogen was attempted. It was recognized that specific methanogen activity depends on the quantity of methanogen, and that gas production does not reflect the condition of methane fermentation. The methane fermentation condition was checked through the specific methanogen activity and analysis of D-CODcr. The target organic loading rate was reached in the short period of about 30 days, and rapid start-up was successfully attained for a full-scale anaerobic digester.

Scattering of in-plane compressional (P) and shear (SV) waves by a polygonal inclusion is studied by using the boundary-element method. We apply the results of the single scattering problem to the propagation of elastic waves in a composite containing a dilute concentration of polygonal inclusions. Numerical calculations are carried out for a moderately wide range of frequencies, and the effect of inclusion shape on the scattering cross sections, and the phase velocities and attenuations of coherent waves and the effective elastic moduli for a dilute composite are shown graphically.

Pt-I-SiC diodes with a thin oxide layer were annealed for 6 h at 600 °C in air. Forward and reverse current-voltage (I-V) and capacitance-voltage (C-V) characteristics were measured in two ambients, 20% O 2 in N 2 and 20% H 2 in N 2 , at room temperature and 300 °C repeatedly. The parameters of the diode as ideality factor, series resistance, change in barrier height were evaluated as a function of the number of repetition times. Annealing has reduced the current, the capacitance and the gas sensitivity in the I-V characteristics, though the stability of the electrical properties of the I-V and C-V characteristics of the diode was maintained under temperature conditions lower than 300 °C. However, the gas sensitivity in the C-V characteristics was not affected by annealing. The results presented in this paper substantiate the possibility of formation of thin oxide layer at SiC surface as mechanism of the degradation of Schottky diode based on SiC.

Small crack kinking in functionally graded materials (FGMs) subjected to a constant initial strain resulting from stress relaxation is studied. The FGMs are modeled as simply nonhomogeneous materials; that is, the effect of microstructure is neglected and the material property variation is considered to be continuous. The material gradation in the FGMs is taken to be of a power-law type. Systematic finite element calculations are made for the energy release rate of the crack. With regard to the local homogeneity, the toughness is taken to be independent of direction; therefore, the crack propagates along the direction of the maximum energy release rate. It is shown that the crack length and the thickness of the surface zone subjected to the initial strain have a strong effect on the kink direction, whereas the material gradients have little effect.

Disposal of anthropogenic CO2 in the ocean has been considered as a method to counteract global warming. A desirable method of the ocean disposal is to convert the less dense liquefied CO2 into denser CO2 hydrate via a submerged hydrate crystallizer at a depth

Fe–Cr–Mn steels have been considered as materials of structural components for fusion reactor because of their low induced-radio-activity compared with SUS316 stainless steels. It has been expected to develop a non-magnetic steel with a high stability of the austenitic phase and a strong resistance to irradiation environments. For these objectives, a series of the Fe–Cr–Mn steels have been examined by tensile tests and simulation irradiation by electrons. The main alloying compositions of the steels developed are; C:0.02–0.2 wt%, Mn: 15 wt%, Cr: 15–16 wt%, N: 0.2 wt%. These steels were heat-treated at 1323 K for 1 h. The structure of the steels after the heat-treatment was austenite single phase. The yield stress of the steels was 350–450 MPa and the elongation were 55–60%. When the steels of high C and N was electron-irradiated at below 673 K, no voids were nucleated and only small dislocation loops were formed with high density. The austenite phase was also stable during irradiation below 673 K. Thus, newly developed high manganese steels have excellent mechanical proprieties and high irradiation resistance at relatively low temperature.

The magnetization of the $\mathrm{Co}({\mathrm{S}}_{1\ensuremath{-}x}{\mathrm{Se}}_{x}{)}_{2}$ system with $0l~xl~0.2$ has been measured under high magnetic fields and high pressure. Ferromagnetic ${\mathrm{CoS}}_{2}$ exhibits a second-order transition at ${T}_{c}=122\mathrm{K}.$ Substitution of 10% Se for S in ${\mathrm{CoS}}_{2}$ reduces the Curie temperature to ${T}_{c}=27\mathrm{K}$ and the transition to first order. $\mathrm{Co}({\mathrm{S}}_{1\ensuremath{-}x}{\mathrm{Se}}_{x}{)}_{2}$ with $0.12l~x$ becomes an exchange-enhanced Pauli paramagnet. The itinerant metamagnetic transition has been observed in the paramagnet. ${\mathrm{C}\mathrm{o}(\mathrm{S}}_{0.9}{\mathrm{Se}}_{0.1}{)}_{2}$ also shows a transition just above ${T}_{c}.$ Using the experimental data, the magnetic phase diagram of $\mathrm{Co}({\mathrm{S}}_{1\ensuremath{-}x}{\mathrm{Se}}_{x}{)}_{2}$ is determined. With increasing pressure, the Curie temperature of ${\mathrm{CoS}}_{2}$ decreases and the ferromagnetic transition changes to first order at $P\ensuremath{\approx}0.4\mathrm{GPa}.$ In the pressure regime of the first-order transition $Pg0.4\mathrm{GPa},$ the metamagnetic transition is observed just above ${T}_{c}.$ In ${\mathrm{C}\mathrm{o}(\mathrm{S}}_{0.9}{\mathrm{Se}}_{0.1}{)}_{2},$ the ferromagnetism disappears at 0.25 GPa and paramagnetism appears. The observed magnetic properties and the magnetic phase diagram of $\mathrm{Co}({\mathrm{S}}_{1\ensuremath{-}x}{\mathrm{Se}}_{x}{)}_{2}$ can be qualitatively described with a theory of the itinerant electron metamagnetism at finite temperatures.

The magnetization of the metamagnetic Co(Si1−xSex)2 system with 0 ⩽ x ⩽ 0.2 has been measured under high pressure and high magnetic field. The magnetic phase diagram is determined in the T−x plane. The metamagnetic behavior under high pressure and high magnetic field and the magnetic phase diagram can be elucidated well with a theory of itinerant electron metamagnetism at finite temperatures.

Sub-seabed disposal is the safest disposal option for CO 2 . Water pressure and dilution into oceanic water prevent direct emission of CO 2 into the air. Sediments under the deep sea floor are usually cool because the deep oceanic water is very cool. CO 2 hydrate forms in the sediments in areas of the sea floor deeper than 300 m. The formation of CO 2 hydrate in sediment pores almost completely prevents the escape of CO 2 .

CO 2 ocean disposal is one of several ways proposed to mitigate the greenhouse gas effect. In this paper, we estimate the cost of various CO 2 disposal options. The system consists of a conventional pulverized coal power plant, CO 2 separation using an amine scrubber, liquefaction and transportation. In this investigation, the power plant and the CO 2 separation plant are common. The liquefaction process and transportation systems are different. We evaluate the costs of pipeline, liquid CO 2 tanker for CO 2 lake, liquid CO 2 tanker dispersion, dry ice tanker and CO 2 dispersion by OTEC. The effect of distance between a power plant and the disposal site, plant size, and plant efficiency on the cost for each case is evaluated. Costs of ocean disposal options are estimated about 90 to 180 per tonne of CO 2 avoided. The least cost transportation option is dependent on the distance between power plant and site. © 1997 Elsevier Science Ltd

Disposal of liquid, anthropogenic CO2 in intermediate-depth ocean waters has been accepted as a means to reduce atmospheric concentrations of this greenhouse species and mitigate global warming. Since the CO2-seawater system is hydrodynamically unstable, liquid CO2 effluent in the ocean will break up into droplets. This paper discusses the influence of both the discharge orifice and properties of CO2 and seawater on the size of CO2 droplets produced. It is found that the droplet size is affected strongly by disposal depth. This suggests that determination of the behavior of CO2 discharged in the ocean must consider not only the orifice configuration, but also fluid properties at the disposal site.

The sub-seabed disposal of CO2 is safer than the disposal of CO2 in inland aquifers. Even if small amounts of CO2 seeped out of sea floor, CO2 would disperse and dissolve into sea water. On the surface of the sea, there exist no depressions where CO2 may concentrate. Sediments under deep sea floor are very cool because the deep oceanic water is usually at a few degrees centigrade. CO2 hydrate is formed in sediments under wide areas of ocean floor deeper than about 300m. Virtually complete isolation of huge amounts of CO2 is possible by the deep sub-seabed disposal. Liquid CO2 with heavy suspension intrudes laterally under light unconsolidated sediments at sea floor deeper than about 3700m. Lateral intrusion technique for the super-deep sub-seabed disposal of CO2 can protect the ecology on the sea floor.

Stability of the hydrate layer formed on the surface of a CO2 droplet in high-pressure and low-temperature water is studied. The criterion for stability of the hydrate layer is found to be xCO2H ≥ 0.098, where xCO2H is the mole fraction of CO2 in the hydrate layer. Because CO2 molecules are not bonded in the hydrate lattice and are smaller than the free diameters of most cavities in the hydrate lattice, CO2 molecules in the hydrate tend to diffuse from the hydrate into water; thus, hydrate formation does not stop mass transfer of CO2 from the droplet into water, albeit the rate of mass transfer is reduced dramatically. xCO2H is regulated by mass transfer of CO2 from the droplet into the hydrate and from the hydrate into water. Accordingly, density and stability of the hydrate layer are influenced significantly by changes in xCO2H. CO2 hydrate is found to be a nonstoichiometric compound. In a freshly formed hydrate layer, xCO2H = 0.115 and xCO2H drops as the hydrate crystal grows. When the thickness of the hydrate layer reaches a critical value at which xCO2H = 0.098, the hydrate layer becomes unstable and collapses into hydrate clusters. Re-establishment of hydrates on the droplet is almost instantaneous. The hydrate layer undergoes a continuous cycle of collapse and re-establishment during the droplet dissolution; thus, it is thermodynamically unstable. However, rapid hydrate formation can maintain hydrates on the droplet, making the hydrate layer chemical-kinetically stable. Since the hydrate layer is thin and the critical thickness is close to that of a freshly formed hydrate layer, the thickness of the hydrate layer appears unchanged over the entire dissolution process.

The behavior of CO2 droplets in intermediate and deep ocean waters has been studied. Because of CO2 hydrate formation on surfaces, CO2 droplets in the ocean cannot, as predicted previously, either be converted into hydrate particles or form a continuous liquid phase. CO2 molecules in the hydrate are found to diffuse readily. As the result, hydrate layers formed on droplets do not stop mass transfer of CO2 from droplets to seawater and, therefore, the CO2 droplets will be dissolved. This predicted fate for CO2 droplets in the ocean agrees with laboratory simulations reported in the literature.

Kinetic studies on the formation of CO 2 hydrate on the surface of a liquid CO 2 droplet in water were conducted. Dimensionless equations for the CO 2 hydration on the surface of a liquid CO 2 droplet were obtained. The thickness of the CO 2 hydrate was investigated in terms of the diffusion coefficient, reaction rate constant, and radius of droplet by the use of dimensionless equations. Some conclusions were obtained from the viewpoint of ocean CO 2 disposal for the reduction of CO 2 emission. When a liquid CO 2 droplet is injected into deep ocean, it will be immediately covered with a very thin film of CO 2 hydrate. It will be very difficult to produce a droplet mostly composed of CO 2 hydrate by liquid CO 2 injection into the ocean.

A repeated dose toxicity study of prulifloxacin, a new antibacterial agent, was conducted in beagle dogs. Male and female dogs were given the test material orally for 4 weeks at doses of 0 (control), 30, 150 and 750 mg/kg. After discontinuation of the treatment, a 4-week recovery test was also conducted. Feces containing white material were seen in the 150 and 750 mg/kg groups. Salivation, prone, lateral or sitting position, gait disturbance, and locomotor depression were observed in the 750 mg/kg group. In this dose group, decreased body weight and food and water consumptions were also observed. There were no treatment-related effects on survival. Ophthalmoscopic and electrocardiographic examinations and urinalysis failed to show any abnormalities related to the treatment. Hematologic examination showed decreased WBC in the 750 mg/kg group. Blood chemical examination revealed increased GPT and alpha 2-globulin in the 750 mg/kg group. Pathological changes caused by the treatment were as follows. Rarefaction of matrix, cavitations and erosions in humeral and femoral articular cartilages, and inflammatory cell infiltration in synovium were seen in the 150 and 750 mg/kg groups. Focal hemorrhage in synovium was also observed in the 750 mg/kg group. In kidney, regeneration of tubular epithelium, inflammatory cell infiltration, fibrosis and crystalline substance in the tubular lumen were observed in the 750 mg/kg group. The above-mentioned changes were satisfactorily reversible except for the changes in the humeral and femoral articular cartilages and in the kidney. Plasma levels and urinary concentrations of active metabolite of the test material were increased in all dose groups with dose-related manner, whereby no sex difference was observed. No effects caused by the repeated dosing were seen in the plasma concentrations. Toxicological findings were not observed in the 30 mg/kg group. The results show that the NOAEL of prulifloxacin is 30 mg/kg for 4-week repeated dose toxicity in dogs.

A study of fertility and fetal development of prulifloxacin, a new antibacterial agent, was conducted in Sprague-Dawley rats. Male rats were given the drug orally from 63 days before mating to the end of the mating period. Female rats were given from 14 days before mating to day 7 of pregnancy. The dose levels for both males and females were 0 (control), 30, 170 and 1000 mg/kg. The females were sacrificed on day 20 of pregnancy for examination of their fetuses. In the 170 mg/kg group, water consumption increased in the female rats, and food consumption decreased and the cecum increased in weight and was enlarged in the males and the females. In the 1000 mg/kg group, body weight gain was suppressed in the males, and food consumption decreased, water consumption increased and cecum increased in weight and enlarged in the males and the females. Moreover, this dose caused white spots and rough surface of the kidney in the males. Prulifloxacin had no adverse effects on reproductive function of the parent animals, and also on development of the fetuses. These results show that the NOAEL of prulifloxacin are 30 mg/kg for general toxicity in parent animals, 1000 mg/kg for reproductive function of parent animals and for development of fetuses.

A repeated dose toxicity study of prulifloxacin, a new antibacterial agent, was conducted in beagle dogs. Male and female dogs were given the test material orally for 13 weeks at doses of 0 (control), 20, 100 and 500 mg/kg. After discontinuation of the treatment, a 5-week recovery test was also conducted. Vomiting, salivation and decreased body weight gain or reduced body weight were seen in the 100 and 500 mg/kg groups. In the 500 mg/kg group, tremor, paresis of posterior limb associated with prone or sitting position and decreased food consumption were also observed. There were no treatment-related effects on survival and water consumption. Ophthalmoscopic, electrocardiographic and hematologic examinations, and urinalysis failed to show any abnormalities attributable to the treatment. Blood chemical examination showed increased GPT and decreased beta- and gamma-globulins in the 100 and 500 mg/kg groups, and increased GOT in the 500 mg/kg group. In pathological examination, cavitations and erosions were seen in the humeral and femoral articular cartilages in the 100 and 500 mg/kg groups. The above-mentioned changes were satisfactorily reversible except for erosions in the humeral and femoral articular cartilages in the 100 and 500 mg/kg groups. No toxicological findings were seen in the 20 mg/kg group. The results show that the NOAEL of prulifloxacin is 20 mg/kg for 13-week repeated dose toxicity in dogs.

The stability of liquid CO 2 in seawater at 3°C under high pressures were investigated by observing the pH and temperature changes around liquid CO 2 as well as its state. There was no distinct change of the state of liquid CO 2 at 37 MPa, while the liquid CO 2 at 32 MPa was unstable. Our experimental investigations suggest that a huge amount of liquid CO 2 can be sequestered for a very long time with reducing CO 2 dissolution and its impacts on ecosystems, if we dispose liquid CO 2 at the depth greater than 3700 m in an ocean.

Sealing of pores and gaps in sedimentary layers by formation of CO 2 hydrate makes artificial caprocks which can prevent the leakage of carbon dioxide from deeper reservoirs of disposed CO 2 . Perfect isolation of CO 2 is possible in cool sedimentary basins under nearly permafrost conditions and in deep and cool submarine sediments. Complete mitigation of greenhouse gas emission from fossil fuel power plants can be realized by deep subseabed disposal and subterranean disposal of carbon dioxide in cool districts.