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Halo distribution is a key topic for background study. This paper has developed an analytical method to give an estimation of beam halo distribution in storage rings. This is a creative new theory. As an example, the equilibrium particle distribution of the beam tail in the Accelerator Test Facility damping ring is calculated analytically with different emittance and different vacuum degree. The analytical results agree the measurements very well. This is a general method, which can be applied to any electron rings.
We discuss the advantages of V2O5-P2O5-Fe2O3-Li2O glass-ceramics as a cathode for lithium-ion batteries. The glass was prepared by using the melt quenching method. The glass-ceramics were produced by heat treatment in air. LixV2O5 crystal was only confirmed as the precipitated phase and the degree of crystallinity was approximately 90%. The total capacity of the glass-ceramics was 340 Ah/kg at a C/20 rate for 1.5-4.2 V cutoff ranges. It is 10% higher than the capacity of the glass cathode. Moreover, the charge-discharge performance of the glass-ceramics cathode showed good cycleability similar to that of the glass. The glass-ceramics had a 83% capacity retention after 40 cycles. These results show that glass-ceramics is a potential candidate for lithium-ion cathode materials.
Although apomixis is the most common form of parthenogenesis in diplodiploid arthropods, it is uncommon in the haplodiploid insect order Hymenoptera. We found a new type of spontaneous apomixis in the Hymenoptera, completely lacking meiosis and the expulsion of polar bodies in egg maturation division, on the thelytokous strain of a parasitoid wasp Meteorus pulchricornis (Wesmael) (Braconidae, Euphorinae) on pest lepidopteran larvae Spodoptera litura (Fabricius) (Noctuidae). The absence of the meiotic process was consistent with a non-segregation pattern in the offspring of heterozygous females, and no positive evidence was obtained for the induction of thelytoky by any bacterial symbionts. We discuss the conditions that enable the occurrence of such rare cases of apomictic thelytoky in the Hymenoptera, suggesting the significance of fixed heterosis caused by hybridization or polyploidization, symbiosis with bacterial agents, and occasional sex. Our finding will encourage further genetic studies on parasitoid wasps to use asexual lines more wisely for biological control.
We studied the electrical properties of thermally treated V2O5-CuO-Fe2O3-P2O5 (vanadate) glasses under reducing high-vacuum conditions. The glasses were prepared by using a melt-quenching method and then applied on Al2O3 substrates as ∼40μm-thick films. The glass films were then heat treated at 375−550°C under a vacuum of 10−6 Pa. Powder X-ray diffraction showed the formation of complex oxides of both MxV2O5 (M = Cu, Fe; x = 0.12−1.3) and vanadium oxides (VOx; x = 1.5−2.5). The resistivity of the glass film crystallized at 550°C measured at 50°C and 300°C were 1.8 × 100 Ωcm and 2.8 × 10−1 Ωcm, respectively, which was 10 times lower than that of the film crystallized in air. The Seebeck coefficient was −132 μV/K at 50°C and −130 μV/K at 300°C. These results show that the vanadate glasses crystallized under the appropriate condition become potential candidate materials for semiconductor and thermoelectric application.
Thermoelectric properties of the Li-doped Cu0.95-xM0.05LixO (M=divalent metal ion; Mn, Ni, Zn) were investigated at the temperature up to 1273 K. In the doped divalent metal ions, Zn2+ ion was the most effective to reduce the thermal conductivity, and the Ni2+ substitution was preferable to decrease the electrical resistivity. For the Cu0.95-xNi0.05LixO sample at x=0.03, the maxima of the dimensionless thermoelectric figure of merit ZT and the power factor P at 1246 K were 4.2×10-2 and 1.6 ×10-4 W/K2m, respectively. The enhancement of the thermoelectric properties of the Li-doped Cu0.95-xM0.05LixO system was discussed.
We report on our growth of superconducting SmFeAs(O,F) films by F diffusion. In our process, F-free SmFeAsO films were grown by molecular beam epitaxy (MBE) first, and subsequently F was introduced into the films via F diffusion from an overlayer of SmF3. We performed a detailed comparison of the growth conditions and also the properties of resultant films for fluoride and oxide substrates. The best films on CaF2 exhibited a high transition temperature, Tcon (Tcend) = 57.8 K (56.4 K) at highest, which may exceed the highest Tc ever reported for bulk samples. Furthermore the films on CaF2 also showed high critical current density over 1 MA/cm2 in self-field at 5 K.
We present the results of our systematic investigation of the RE dependency of superconductivity in the parent compounds T’-RE2CuO4 (RE = Pr, Nd, Sm, Eu, Gd, and Tb). Superconducting samples were prepared by metal organic decomposition (MOD). A stringent control of synthesis- and post-annealing-conditions is required to obtain superconducting samples. Superconductivity with a transition temperature (Tconset) ≥ 30 K is achieved for RE = Pr and Nd. By contrast, Tconset is at highest 20 K for RE = Gd. Our results indicate that the induction of superconductivity into T’-RE2CuO4 cuprates strongly depends on the RE3+ ionic size. This trend is discussed from the viewpoint of RE-dependent thermodynamic stability of T’-RE2CuO4. For smaller RE3+ ions, the thermodynamic boundary conditions become tighter.
Single-crystalline films of superconducting Sr1-xKxFe2As and Ba1-xKxFe2As2 were grown by molecular beam epitaxy (MBE). The most crucial problem in MBE growth of these compounds is the high volatility of elemental K. The key to incorporating K into films is low-temperature growth (≤ 350 ºC) in reduced As flux. We performed a systematic study of the doping dependence of Tc in Ba1-xKxFe2As2 for x = 0.0 to 1.0. The highest Tcon (Tcend) so far attained for Ba1-xKxFe2As2 is 38.3 K (35.5 K) at x ~ 0.3.
This study examined the crystallization of vanadate glasses by using microwave irradiation. A second aim was comparing the thermoelectric properties of crystallized glasses when using microwave irradiation to conventional heating. V2O5-P2O5-Fe2O3-CuO glasses were prepared by using the melt quenching method. These glasses were irradiated by 2.45-GHz microwaves and heated in an electric furnace. MxV2O5 (M= Cu, Fe x=0.26-055) crystals were selectively precipitated by using the microwave irradiation. The crystal growth was also promoted by it. As a result, precipitation crystals formed a fiber-like structure. The electrical conductivity of the microwave irradiated glass was 6.3×101S/m at room temperature, which was three times higher than the value of conventionally-heated glass. The Seebeck coefficient of the microwave irradiated glass was -127 μV/K at room temperature, which was two times higher than that of conventionally-heated glass. This caused the power factor to be improved about 12 times. These results show that microwave irradiation is a potential candidate for obtaining conductive crystallized vanadate glasses.
The phase decomposition of the Al-rich γ TiAl intermetallic compound in the TiAl(L10) and Ti3Al5(P4/mbm) two phases region is investigated experimentally. On the phase decomposition of the Ti-56at%Al alloy, the single precipitate(Ti3Al5) shape is an oblate spheroid at the early stage of precipitation and each particle is aligned along certain direction of the orientation about 20 degrees from . During coarsening, the precipitates encounter each other, then, the shape of the particle becomes the slanted or bended plate. In the case of phase decomposition of the Ti-58at%Al alloy, the tweed-like structure is observed at the beginning of the aging. The precipitates are connected each other during coarsening, finally the microstructure becomes the large layered structure with a zigzag-shaped interface. These microstructure changes are simulated based on the phase field model. The morphology and the time development of the simulated microstructure are in good agreement with the experimental results.
One solution to reduce the time constant of ultra large scale integrated circuit (ULSI) is the use of a low dielectric constant intermetal film like fluorinated silicon oxide (SiOF). We could obtain SiOF films with low dielectric constant as low as 2.6 and good step coverage by adding CF4 to SiH4 and N2O in plasma-enhanced chemical vapor deposition (PECVD) process. To investigate the dielectric constants due to each polarization and the reason for the decrease in the dielectric constant, we used capacitance-voltage (C-V) and ellipsometry measurements, and Kramers-Kronig transformation. The decrease in dielectric constant could not be completely explained by the reduction in ionic and electronic polarization. We could detect silanol groups, Si-OH in the films and their decrease with increasing CF4 flow rate. It is suggested that the main polarization component to decrease dielectric constant is such as orientational polarization. The step coverage of film was improved by adding CF4. It is suggested that the reduction in the sticking probability of films forming species due to the change in surface state improved the step coverage.
Environmentally friendly organic-inorganic hybrid materials with repellent activity against marine fouling organisms have been developed using interpenetrating polymer networks (IPNs), composed of a three-dimensional silica matrix of tetraethoxysilane (TEOS) and chain-like polymers, such as poly(methylmethacrylate) (PMMA) and poly(vinylacetate) (PVAc). The repellent activity of the IPNs reached a maximum of approximately 90% relative to that of tetrabutyl tin oxide (TBTO). Simple bioassays using blue mussels and algae were used to screen out the adequate proportions of those components.
We report on the results from 3-D SPH simulations of TeV binaries with Be stars. Since there is only one TeV binary (B 1259-63) where the nature of the compact companion has been established, we mainly focus on this Be-pulsar system. From simulations of B 1259-63 around periastron, we find that the pulsar wind dominates the Be-star wind and strips off an outer part of the Be-star disk, causing a strongly asymmetric, phase-dependent structure of the circumstellar material around the Be star. Such a large modulation may be detected by optical, IR, and/or UV observations at phases near periastron. We also discuss the results from simulations of another TeV binary LS I+61 303, for which the nature of the compact object is not yet known.
There are few data on circulatory pro-inflammatory cytokine levels and cytokine gene polymorphisms in H. pylori-positive patients. A cross-sectional study was conducted to examine the effects of H. pylori infection, gastric atrophy, and the IL-8 T-251A polymorphism on plasma IL-8 levels in 98 Japanese adults. Seventy-one subjects were positive for H. pylori infection. The geometric mean of plasma IL-8 concentration was significantly higher in subjects with H. pylori infection than in those without (P=0·001). The development of atrophy was negatively associated with IL-8 levels in the H. pylori-positive subjects, although not significantly. Plasma IL-8 levels in the T/T genotype were associated with H. pylori infection and atrophy status (P=0·016). Our findings suggested that circulating IL-8 levels were associated with H. pylori infection. The effect of H. pylori infection on plasma IL-8 levels was not clearly modified by the IL-8 T-251A polymorphism.
A significant difference of strength was noted in alumina ceramics made through the powder compaction process with spray dryers of two sizes. The origin of the change was examined by new characterization methods involving optical microscopy. The granules were found to have irregular shape. Defects in compacts were formed from these dimples and also from the nonuniform packing of powder particles at the granule boundaries. These defects are responsible for major defects in sintered bodies. The change of strength in the ceramics can be explained by the change of granule size with the spray dryer. The size of granules was found to directly affect the size of defects in the green and sintered bodies. The size of granules, defects in granules, green bodies, and sintered bodies were approximately 20–30% smaller for granules made with the small spray drier. There was a direct correlation between the size of defect and the strength of ceramics.
The successful synthesis of high-Tc YBa2Cu3O7 films by means of electron-beam codeposition are reported. Several important growth parameters have been surveyed in a preliminary way. The substrates investigated include Al2O3, ZrO2, MgO, and SrTiO3, The films were characterized by resistivity measurements, x-ray diffraction, microprobe, and Rutherford backscattering analysis. Some TEM and critical current density studies were also carried out. The best results to date have been obtained on SrTiO3 substrates with which polycrystalline epitaxial growth has been achieved. Resistive superconducting transitions with zero resistance at 89.5 K and a 2 K width have been observed in these films.
1. Semi-synthetic diets containing 200 g protein/kg were meal-fed for 1.5 h to groups of rats. The contents of the whole small intestinal tract were collected and the amount of soluble calcium was determined.
2. In the rats given 200 g casein/kg diet, formation of a fraction containing macrophosphopeptide in the small intestine was confirmed by gelfiltration of the intestinal contents on Sephadex G-25. However, this macrophosphopeptide fraction was not found when casein alone was fed.
3. In the intestinal contents at 2.5 h after ingestion, the amounts of both soluble Ca and phosphorus were significantly higher in rats fed the casein diet than in those fed diets containing egg albumin, isolated soyabean protein or an amino acid mixture. However, the amount of insoluble Ca was least in rats fed the casein diet.
Lactation was induced in 30 Holstein heifers by treatment with synthetic oestrogen only. The average age of the heifers at the start of treatment was 16·6 months and the average lactation yield 1072 kg of milk with a fat content of 3·43% given in 241 days. Subsequently, 22 of these animals gave a normal lactation starting at an average age of 31 months, with yields of 3980 kg milk with a fat content of 3·31% given in 294 days. The induced lactation was slightly associated with reproductive problems and growth of the animals was normal. There was a good within-cow correlation between the yield and composition of the milk obtained in the 2 lactations. The correlation coefficients between the total production of the milk in the normal lactation and the total yield and peak production in the induced lactation were 0·718 and 0·785 and that between the average percentages of fat in the milk obtained in the 2 lactations was 0·718.
It is possible to predict dairy performance from the performance during the induced lactation, but before the procedure can be recommended for general use the question whether it may induce reproductive difficulties requires further investigation.
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