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151.
Nagasawa S. Tahara S. Numata H. Tsuchida S. 《Applied Superconductivity, IEEE Transactions on》1994,4(1):19-24
We have developed the smallest Josephson nondestructive read-out (NDRO) memory cell, called a vortex transitional (VT) memory cell, for a Josephson high-speed 16-Kbit RAM. Its size is 22×22 μm2 , which is only 16% of the size of previously developed VT memory cells used in Josephson 4-Kbit RAM. This is achieved by developing a vertically integrated device structure and refining small-junction technology. The cell consists of Nb/AlOx/Nb junctions, three Nb wirings, SiO2, insulators and Mo resistors. The VT memory cells operate properly, with a large operating margin of ±20% 相似文献
152.
H Nagasawa S Morii R Furuichi Y Iwai M Iwai T Mori Y Goto 《Canadian Metallurgical Quarterly》1993,27(4):358-363
Isologous anterior pituitary grafting, 4 each, to 3-4-month-old SHN and SLN male mice resulted in an appearance of mammary tumours from 8 months of age and the incidence at 12 months reached 53.8% in each strain. All tumours were diagnosed as type B adenocarcinomas. In association with the results, normal mammary gland growth and mouse mammary tumour virus (MMTV)-gp52 antigen levels in the submaxillary glands were stimulated by the treatment in these strains. The effect of pituitary grafting was much less in GR/A male mice in which no mammary tumours appeared. 相似文献
153.
154.
The effects of incorporated poly(d-lactic acid) (PDLA) as poly(lactic acid) (PLA) stereocomplex crystallites on the isothermal and non-isothermal crystallization behavior of poly(l-lactic acid) (PLLA) from the melt were investigated for a wide PDLA contents from 0.1 to 10 wt%. In isothermal crystallization from the melt, the radius growth rate of PLLA spherulites (crystallization temperature (Tc)≥125 °C), the induction period for PLLA spherulite formation (ti) (Tc≥125 °C), the growth mechanism of PLLA crystallites (90 °C≤Tc≤150 °C), and the mechanical properties of the PLLA films were not affected by the incorporation of PDLA or the presence of stereocomplex crystallites as a nucleating agent. In contrast, the presence of stereocomplex crystallites significantly increased the number of PLLA spherulites per unit area or volume. In isothermal crystallization from the melt, at PDLA content of 10 wt%, the starting, half, and ending times for overall PLLA crystallization (tc(S), tc(1/2), and tc(E), respectively) were much shorter than those at PDLA content of 0 wt%, due to the increased number of PLLA spherulites. Reversely, at PDLA content of 0.1 wt%, the tc(S), tc(1/2), and tc(E) were longer than or similar to those at PDLA content of 0 wt%, probably due to the long ti and the decreased number of spherulites. This seems to have been caused by free PDLA chains, which did not form stereocomplex crystallites. On the other hand, at PDLA contents of 0.3-3 wt%, the tc(S), tc(1/2), and tc(E) were shorter than or similar to those at PDLA content of 0 wt% for the Tc range below 95 °C and above 125 °C, whereas this inclination was reversed for the Tc range of 100-120 °C. In the non-isothermal crystallization of as-cast or amorphous-made PLLA films during cooling from the melt, the addition of PDLA above 1 wt% was effective to accelerate overall PLLA crystallization. The X-ray diffractometry could trace the formation of stereocomplex crystallites in the melt-quenched PLLA films at PDLA contents above 1 wt%. This study revealed that the addition of small amounts of PDLA is effective to accelerate overall PLLA crystallization when the PDLA content and crystallization conditions are scrupulously selected. 相似文献
155.
S. Nagasawa Y. Yamashita Y. Fukuzawa 《International Journal of Mechanical Sciences》2010,52(9):1101-1106
The out-of-plane shearing characteristics of a paperboard by a straight punch and dies are important to estimate the paperboard stripping performance. In this paper, in order to reveal the die clearance effect and the feed velocity effect on the sheared end-profile of the paperboard, a precision shear testing device was developed. The shear cutting of the paperboards was experimentally carried out by varying the die clearance and the feed velocity of punch. Through this work, it was confirmed that (1) the load response had two kinds of transition gradient before passing through the maximum load point; (2) the shearing performance was classified with the normalized indentation depth d/t=0.1∼0.2 into an out-of-plane shear mode and a combined shear mode. Here, the combined mode was composed of out-of-plane bending and in-plane tensile deformation; (3) the surface layers of paperboard were observed with a de-lamimated state using an image processing of side-view flow deformation of the paperboard. Furthermore, (4) the shear strength was discussed with the orthotropic properties of the paperboard. 相似文献
156.
Hiroki Ohira Naota Torii Taku M. Aida Masaru Watanabe Richard L. Smith Jr. 《Separation and Purification Technology》2009,69(1):102-108
Shikimic acid can be rapidly separated (ca. 5 min) from Chinese star anise with hot water extraction at temperatures of 120 °C or higher to obtain recoveries of 100%. Extraction recoveries of shikimic acid close to 97% can be obtained with water at 70 °C using slightly longer extraction times (ca. 10 min) than those at 120 °C. A semi-batch flow apparatus was used to study the effect of temperature, average particle size, water flow rate, and extraction time on the experimental recoveries. For 0.5 g Chinese star anise raw material that contained ca. 8% shikimic acid, 100% recoveries of shikimic acid could be obtained with 60 g water at 150 °C at 15 MPa in 4 min for star anise material having a particle size range from 355 to 600 μm. A one-site kinetic model was found to provide good correlation of the data and the kinetic parameters of the model could be written in terms of linearized contributions in temperature, average particle diameter and flow rate. 相似文献
157.
Takakazu Yamamoto Hiroki Fukumoto Take-aki Koizumi 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(1):3-11
π-Conjugated chelating polymers such as poly(2,2′-bipyridine-5,5′-diyl), poly(1,10-phenanthroline-3,8-diyl), and salophen
polymers have been prepared by organometallic polycondensations. The obtained polymers form metal complexes with various metal
species such as [Ru(bpy)2]2+ and CuCl2. Metal complexes of π-conjugated ligands are also polymerized by dehalogenative organometallic polycondensations. Some of
the metal complexes of π-conjugated polymers exhibit electrical conducting nature and show catalytic activity for redox reactions. 相似文献
158.
Yoshinobu Murakami Hiroki Kitani Jotaro Shirai Masayuki Nagao Norikazu Naito Kazuhisa Hatano Hirotoshi Kawamura 《Electrical Engineering in Japan》2012,180(3):9-17
This paper reports a study on the possibility of an aerial flashover between a coil conductor and a casing in rotating machines under the application of a lower voltage than Paschen's voltage, even when enough insulation distance is secured. The time lag to aerial flashover originating from surface flashover was measured. To understand the aerial flashover influenced by the parameters of the voltage application circuit, the aerial flashover distance was measured using a cable which had a simulated pore to confirm the above issue. The surface flashover characteristic was also measured using a photomultiplier tube (PMT). It became clear that aerial flashover occurred a few milliseconds after surface flashover generation. After showing the peak, the aerial flashover distance decreased with increasing time constant. The surface flashover time estimated by the PMT output exhibited different values with change of capacitance when the time constant is larger. On the other hand, the average surface flashover current was almost the same in spite of the change of capacitance. From these results, it was concluded that the aerial flashover distance was influenced by the time constant of the circuit. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(3): 9–17, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21295 相似文献
159.
Okochi M Hayashi H Ito A Kato R Tamura Y Sato N Honda H 《Journal of Bioscience and Bioengineering》2008,105(3):198-203
Heat shock protein 70 (Hsp70) family members are known as facilitators of immune responses by interacting with receptors on antigen-presenting cells leading to Hsp70-peptide uptake and antigen cross priming. Here, identification of human leukocyte antigen (HLA)-A24-restricted epitopes was achieved using peptide arrays for evaluation of their affinities to Hsp70 and HLA-A24 binding prediction tools. Using Hsp70 as the model antigen, the GYPVTNAVI and VFQHGKVEI peptides were identified as antigens. These peptides actually bound to HLA-A24 in the stabilization assay using T2-A*2402 cells, and induced a strong peptide-reactive cytotoxic T lymphocyte response in HLA-A24 transgenic mice after vaccination. 相似文献
160.
Hirayama H Sawai K Moriyasu S Hirayama M Goto Y Kaneko E Miyamoto A Ushizawa K Takahashi T Minamihashi A 《Reproduction (Cambridge, England)》2008,136(5):639-647
We conducted this study to elucidate a factor causing a poor sign of parturition and prolonged gestation, which is frequently observed in cows carrying somatic clone fetuses. Pre-partum rises in concentrations of plasma estrone and estradiol-17beta in the recipient cows pregnant with clones were subtle. By contrast, the plasma concentration of estrone sulfate in clone pregnancies increased gradually from pre-initiation of parturition induction whereas control cows that received in vivo-derived embryos showed a significant increase at parturition. Therefore, in clone pregnancies, the ratio of estrone/estrone sulfate was low during the pre-partum period compared with control. Messenger RNA expression of estrogen sulfotransferase (SULT1E1) in the placenta at parturition was significantly higher in clone pregnancies than control pregnancies and was localized in binucleate cells (BNC). SULT1E1 mRNA abundance was negatively and positively correlated with concentrations of maternal estrone and estrone sulfate at parturition respectively. Messenger RNA expressions of estrogen sulfatase (STS) and aromatase (CYP19) were similar between clone and control pregnancies and were localized in BNC and caruncular epithelial cells. STS and CYP19 mRNA abundances showed positive correlations with maternal estradiol-17beta concentration. The population of BNC in the placenta did not differ between clone and control pregnancies. Plasma cortisol concentration of vaginally delivered newborn clone calves was comparable with those of control, although cesarean section delivered clone calves showed a low concentration. These results suggest that excess estrogen sulfoconjugation is the reason for the perturbed low ratio of active to inactive estrogens and the resulting hormonal imbalance contributes to the lack of overt signs of readiness for parturition in cows pregnant with clones. 相似文献