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61.
Kuga Yoshikazu Okauchi Keiko Takeda Daiki Ohira Yuichi Ando Koji 《Journal of nanoparticle research》2001,3(2-3):175-183
Size distribution measurements and classification tests by a low pressure differential mobility analyzer (LPDMA) for nanometer-sized silver particles and cesium iodide particles under low pressure conditions (123–300 Torr) were performed using a transmission electron microscope (TEM) and the tandem DMA technique. When the ratio of the sheath gas flow rate and the aerosol gas flow rate was set at 5 : 1, the targeted sizes calculated from the classification voltage applied to the LPDMA at 160 Torr are found to be in good correlation with the count mean Feret diameter obtained from the TEM observation of the particles collected after a classification ranging from 6 to 25 nm, although the targeted sizes set by the LPDMA were approximately 15% greater than the count mean Feret diameter measured by the TEM after classification. The geometric standard deviations of DMA-classified particles measured by TEM and those obtained from the tandem DMA method ranged from 1.08 to 1.17 and from 1.05 to 1.13, respectively. They were slightly greater than the ideal geometric standard deviations (1.05) of the particles classified with the LPDMA, which was calculated by neglecting the broadening effects due to Brownian diffusion. We experimentally demonstrated the validity of our LPDMA system for size measurements and classification of the nanometer-sized particles under low pressure conditions. 相似文献
62.
Kazuki Matsumoto Jun Katsuyama Ryo Sugiyama Yasuaki Takizawa Seita Ishii Mitsuru Shinagawa Yuichi Kado 《Optical Review》2014,21(5):614-620
In this paper, we describe an induced signal measurement on the human body for developing a high-performance transceiver of an intra-body communication system. It is important to isolate awearable transceiver from an electrical instrument for precise measurement. We have developed a probe system using an optical isolation method including a laser diode, photo-diode, and optical fiber. The probe system can be successfully applied to the precise measurement of a receiving signal power at a wearable transceiver. We verify that the experimental results agree with the simulation results based on our previous channel model of intra-body communication. 相似文献
63.
Akinari Minegishi Akihiro Nishioka Tatsuhiro Takahashi Yuichi Masubuchi Jun-ichi Takimoto Kiyohito Koyama 《Rheologica Acta》2001,40(4):329-338
A series of polystyrene (PS) and a small amount of ultra high molecular weight (UHMW) PS blends have been prepared by using
tetrahydrofuran (THF). Matrix PS has an Mw of 423,000 (Mw/Mn= 2.36) and UHMW-PS has either an Mw of 3,220,000 (Mw/Mn= 1.05) or 15,400,000 (Mw/Mn=1.30) in the range of concentration from 0 wt% to 1.5 wt%. The influence of a small amount of UHMW on dynamic viscoelasticity
was investigated. At the frequency lower than 0.001 rad/s, the enhancement of G′ was observed by the incorporation of a small
amount of UHMW. And the degree of enhancement was in the order of Mw of UHMW and its concentration. The measurement of uniaxial elongational viscosity for the blends was performed and the effects
of UHMW on strain-hardening properties were analyzed at equal strain-rate conditions. The concentration of UHMW where the
strain-hardening becomes substantially stronger was determined. To get more insight into the cause of enhancement of strain-hardening
at a certain concentration, the damping function from step-shear stress relaxation was measured. The influence of a small
amount of UHMW on the damping function was found to be small. It was interpreted, from time- and strain-dependency points,
that the enhancement of strain-hardening by a small amount of UHMW was governed by the long relaxation time.
Received: 6 September 2000 Accepted: 11 January 2001 相似文献
64.
We introduce a new homology theory of quandles, called simplicial quandle homology, which is quite different from quandle homology developed by Carter et al. We construct a homomorphism from a quandle homology group to a simplicial quandle homology group. As an application, we obtain a method for computing the complex volume of a hyperbolic link only from its diagram. 相似文献
65.
Guksik Lee Fumito Araoka Ken Ishikawa Yuichi Momoi Osamu Haba Koichiro Yonetake Hideo Takezoe 《Particle & Particle Systems Characterization》2013,30(10):847-852
Ordering transitions are observed in azo‐dendrimer‐dissolved nematic liquid crystal (NLC) droplets dispersed in a glycerol matrix. The dendrimer molecules are spontaneously attached at the interface between NLC and glycerol, so that the nematic directors orient perpendicular to the interface, in the radial configuration. Photoisomerization makes the directors be tangential to the interface, in a photoinduced ordering transition from radial to bipolar structure. Similar experiments are conducted both in cholesteric (Ch) and smectic‐A (SmA) LC droplets. Complicated photoinduced ordering transitions are also observed in Ch and SmA droplets, and the associated molecular orientation changes are discussed. Photoisomerizable azo‐dendrimer molecules provide a possible way to control orientation, even in microdroplet systems in which the interface cannot be treated by conventional surface agents. 相似文献
66.
Background
BIR family proteins are evolutionarily conserved anti-apoptotic molecules. One member of Xenopus BIR family proteins, xEIAP/XLX, is a weak apoptosis inhibitor and rapidly degraded in a cell-free apoptotic execution system derived from interphase egg extracts. However, unfertilized eggs are naturally arrested at the metaphase of meiosis II by the concerted activities of Mos-MEK-p42MAPK-p90Rsk kinase cascade (cytostatic factor pathway) and many mitotic kinases. Previous studies suggest that cytostatic factor-arrested egg extracts are more resistant to spontaneous apoptosis than interphase egg extracts in a p42MAPK-dependent manner. We tested whether xEIAP/XLX might be phosphorylated in cytostatic factor-arrested egg extracts, and also examined whether xEIAP/XLX could be functionally regulated by phosphorylation. 相似文献67.
68.
Yutaka Natsume Junji Yamauchi Ryoichi Tazawa Koji Ishikawa Shigeru Kawaguchi Yuichi Yamamoto Hisamatsu Nakano 《光学学报》2003,23(Z1)
Phase adjustment elements called islands and peninsulas are introduced to obtain an AWG demultiplexer with a flat spectral response. Use of the peninsulas enables us to achieve a 1dB bandwidth of 0.5 nm. 相似文献
69.
70.
Ketone zincate-type enolates can be applied to radical trifluoromethylation for the general synthesis of α-CF3-ketones, cyclopentanones in particular. The addition of diethylzinc to lithium enolates is the key in the preparation of the zincate-type enolates for efficient radical trifluoromethylation. 相似文献