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1.
2.
Keita Ikeue Shingo Ando Tomohiro Mitsuyama Yusuke Ohta Keishi Arayama Akiko Tsutsumi Masato Machida 《Topics in Catalysis》2008,47(3-4):175-180
Lanthanide-based oxysulfides and sulfide, LnTaO3.5S0.5, Ln10OS14 (Ln = La, Pr, Nd, Sm) and La4In5S13, were successively synthesized by sulfurization in a flowing H2S. The sulfurization decreased the band-gap energies from >4 eV to <3eV, because of the formation of occupied S3p orbitals
on the top of valence band. In accordance with the small band gap, the H2 evolution from a 0.01 M Na2S and 0.01 M Na2SO3 solution system was observed under irradiation of light up to >500 nm. The rate of H2 evolution under light irradiation of >500 nm increased in the order of Ni/LaTaO3.5S0.5 < Ru/La10OS14 < Pt/La4In5S13. 相似文献
3.
Hiraki M. Uano K. Minami M. Sato K. Matsuzaki N. Watanabe A. Nishida T. Sasaki K. Seki K. 《Solid-State Circuits, IEEE Journal of》1992,27(11):1568-1574
A BiCMOS logic circuit applicable to sub-2-V digital circuits has been developed. A transiently saturated full-swing BiCMOS (TS-FS-BiCMOS) logic circuit operates twice as fast as CMOS at 1.5-V supply. A newly developed transient-saturation technique, with which bipolar transistors saturate only during switching periods, is the key to sub-2-V operation because a high-speed full-swing operation is achieved to remove the voltage loss due to the base-emitter turn-on voltage. Both small load dependence and small fan-in dependence of gate delay time are attained with this technique. A two-input gate fabricated with 0.3-μm BiCMOS technology verifies the performance advantage of TS-FS-BiCMOS over other BiCMOS circuits and CMOS at sub 2-V supply 相似文献
4.
Usami K. Igarashi M. Minami F. Ishikawa T. Kanzawa M. Ichida M. Nogami K. 《Solid-State Circuits, IEEE Journal of》1998,33(3):463-472
This paper describes an automated design technique to reduce power by making use of two supply voltages. The technique consists of structure synthesis, placement, and routing. The structure synthesizer clusters the gates off the critical paths so as to supply the reduced voltage to save power. The placement and routing tool assigns either the reduced voltage or the unreduced one to each row so as to minimize the area overhead. The reduced supply, voltage is also exploited in a clock tree to reduce power. Combining these techniques together, we applied it to a media processor chip. The combined technique reduced the power by 47% in random-logic modules and by 73% in the clock tree, while keeping the performance 相似文献
5.
Cutaneous lesions caused by M. ulcerans were shown to bear only a superficial resemblance to those produced by certain spider species. M. ulcerans was not found in either the venoms or the midguts of several Australian spiders, and deliberate contamination by inoculation of the fangs and digestive system of the wolf spider, Lycosa godeffroyi, did not result in permanent colonization. M. ulcerans was successfully introduced into the skin of mice through a small trauma site similar to that caused by a spider bite. However, because M. ulcerans was shown to survive on exposed surfaces for only a short period, a successful inoculation is likely only if the skin is contaminated with this organism after, or at the same time as, the skin suffers damage. The claim by other workers that M. ulcerans produces cutaneous ulcers by release of an exotoxin could not be confirmed. The authors conclude that M. ulcerans is not involved in most cases of necrotic arachnidism and hence there is no justification for prescribing anti-mycobacterial antibiotics to resolve alleged spider bite lesions unless the presence of M. ulcerans has been demonstrated by appropriate laboratory tests. 相似文献
6.
7.
Akihiro Yamada Kuniko Kojima Koji Minami Hiroaki Sugiura Hiroshi Kida Kenji Samejima 《Journal of the Society for Information Display》2012,20(7):390-396
Stationary projectors mainly used in system applications have recently gained a wider application range, including general presentations in halls and large conference rooms and being used, for example, in digital signage and for monitoring purposes. Consequently, they are required to meet new market demands for durability, reliability, and flexibility in installation in addition to their conventional basic performance such as especially high brightness. To achieve especially high brightness, a new optical system with two lamps is proposed; the profile of the cover glass that prevents the glass from scattering is made aspherical, the profile of the beam‐combining mirror is improved with its position optimized, and the size of the incident plane of the integrator rod is made larger (1.1 times). These measures resulted in an optical system of an even higher efficiency with 7000 lm, which is the highest in its class (according to a June 2010 investigation). Also, the arrangement of two parallel lamps completely eliminated the effect of heat passing from one lamp to the other, which helped secure durability, reliability, and flexibility in installation. Furthermore, the combined use of the unique non‐telecentric optical system, adopted from the conventional single‐lamp model, helps maintain the class‐highest contrast ratio.1,2 相似文献
8.
F. Minami A. Brückner-Foit D. Munz B. Trolldenier 《International Journal of Fracture》1992,54(3):197-210
The local approach was recently proposed by Beremin and Mudry for evaluating the statistical behaviour of toughness results of materials. This approach introduces a stress parameter
w
, termed the Weibull stress, as a measure of the fracture resistance of materials instead of the conventional toughness parameters such as K
c,
c
and J
cl (critical stress intensity factor, CTOD and J-integral, respectively). The Weibull stress
w
obeys the Weibull distribution with the two parameters m and
u
(the shape and the scale parameter, respectively). The first parameter m is normally estimated to be 22 irrespective of the kind of material. In this paper a procedure for the determination of the Weibull parameters m and
u
is developed. This procedure consists of the determination of the plastic zone ahead of the crack tip, from which cleavage fracture originates, and of the maximum likelihood estimation of the parameters m and
u
based on the stress distribution in the plastic zone. Calculations using this procedure confirm that the distribution of the Weibull stress
w
is a material property independent of specimen thickness, and in particular that the shape parameter m depends on the material, e.g. m12 for a German reactor pressure vessel steel (20 Mn Mo Ni 5 5). Using these parameters for the distribution of the Weibull stress the size effect in fracture toughness values is predicted and an improved agreement between theory and experiments is obtained compared to the Weakest Link model. 相似文献
9.
10.
Sachi Oshima Shunichi Asai Naohiko Seki Chikashi Minemura Takashi Kinoshita Yusuke Goto Naoko Kikkawa Shogo Moriya Atsushi Kasamatsu Toyoyuki Hanazawa Katsuhiro Uzawa 《International journal of molecular sciences》2021,22(12)
We identified the microRNA (miRNA) expression signature of head and neck squamous cell carcinoma (HNSCC) tissues by RNA sequencing, in which 168 miRNAs were significantly upregulated, including both strands of the miR-31 duplex (miR-31-5p and miR-31-3p). The aims of this study were to identify networks of tumor suppressor genes regulated by miR-31-5p and miR-31-3p in HNSCC cells. Our functional assays showed that inhibition of miR-31-5p and miR-31-3p attenuated cancer cell malignant phenotypes (cell proliferation, migration, and invasion), suggesting that they had oncogenic potential in HNSCC cells. Our in silico analysis revealed 146 genes regulated by miR-31 in HNSCC cells. Among these targets, the low expression of seven genes (miR-31-5p targets: CACNB2 and IL34; miR-31-3p targets: CGNL1, CNTN3, GAS7, HOPX, and PBX1) was closely associated with poor prognosis in HNSCC. According to multivariate Cox regression analyses, the expression levels of five of those genes (CACNB2: p = 0.0189; IL34: p = 0.0425; CGNL1: p = 0.0014; CNTN3: p = 0.0304; and GAS7: p = 0.0412) were independent prognostic factors in patients with HNSCC. Our miRNA signature and miRNA-based approach will provide new insights into the molecular pathogenesis of HNSCC. 相似文献