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101.
Nakamori H Matsuyama S Imai S Kimura T Sano Y Kohmura Y Tamasaku K Yabashi M Ishikawa T Yamauchi K 《The Review of scientific instruments》2012,83(5):053701
To construct adaptive x-ray focusing optics whose optical parameters can be varied while performing wavefront correction, ultraprecise piezoelectric deformable mirrors have been developed. We computationally and experimentally investigated undesirable short-period deformation caused by piezoelectric actuators adhered to the substrate during mirror deformation. Based on the results of finite element method analysis, shape measurements, and the observation of x-ray reflection images, a guideline is developed for designing deformable mirrors that do not have short-period deformation errors. 相似文献
102.
Ya Nan Ye Martin Frauenlob Lei Wang Masumi Tsuda Tao Lin Sun Kunpeng Cui Riku Takahashi Hui Jie Zhang Tasuku Nakajima Takayuki Nonoyama Takayuki Kurokawa Shinya Tanaka Jian Ping Gong 《Advanced functional materials》2018,28(31)
Tough and self‐recoverable hydrogel membranes with micrometer‐scale thickness are promising for biomedical applications, which, however, rarely be realized due to the intrinsic brittleness of hydrogels. In this work, for the first time, by combing noncovalent DN strategy and spin‐coating method, we successfully fabricated thin (thickness: 5–100 µm), yet tough (work of extension at fracture: 105–107 J m?3) and 100% self‐recoverable hydrogel membranes with high water content (62–97 wt%) in large size (≈100 cm2). Amphiphilic triblock copolymers, which form physical gels by self‐assembly, were used for the first network. Linear polymers that physically associate with the hydrophilic midblocks of the first network, were chosen for the second network. The inter‐network associations serve as reversible sacrificial bonds that impart toughness and self‐recovery properties on the hydrogel membranes. The excellent mechanical properties of these obtained tough and thin gel membranes are comparable, or even superior to many biological membranes. The in vitro and in vivo tests show that these hydrogel membranes are biocompatible, and postoperative nonadhesive to neighboring organs. The excellent mechanical and biocompatible properties make these thin hydrogel membranes potentially suitable for use as biological or postoperative antiadhesive membranes. 相似文献
103.
104.
105.
Hirano A. Tsuda H. Kobayashi H. Takahashi R. Asobe M. Sato K. Hagimoto K. 《Lightwave Technology, Journal of》1999,17(5):873-884
This paper proposes an all-optical regenerator utilizing a novel all-optical discriminator. The impacts of nonlinearity of optical gates on discrimination performance are estimated. The evaluation of discrimination performance shows that amplified spontaneous emission noise and wave form distortion in optical signals can be effectively suppressed. We experimentally demonstrate the suppression using a low-temperature-grown optical switch up to 10 Gb/s 相似文献
106.
Katsuyuki Tsuda Ken'ichi Tsutsumi Manabu Yaegashi Masahiro Miyajima Takashi Ishizone Akira Hirao Fumiaki Ishii Toyoji Kakuchi 《Polymer Bulletin》1998,40(6):651-658
Summary
The radical polymerizations of 2-, 3-, and 4-(phenylethynyl)styrenes (1a–c) and the copolymerizations of 1a–c (M1) with styrene (M2) were carried out using AIBN as the initiator in toluene at 60°C. The number-average molecular weights (M
ns) were extremely low for poly(2-phenylethynylstyrene) (2a) and poly[(phenylethynyl)styrene-co-styrene] (3a), and increased in the order of 2a, 3a << 2b, 3b < 2c, 3c. Monomer reactivity ratios were determined as r
1= 1.80 and r
2= 0.51 for 1a, r
1= 1.72 and r
2= 0.53 for 1b, and r
1= 3.17 and r
2= 0.24 for 1c. Polymers 2a–c and 3a–c underwent an exothermic reaction at elevated temperature to form organic solvent-insoluble polymers. Although the decomposition
of 2a was observed from 200°C, 2b and 2c exhibited a high heat-resistance property in both nitrogen and air atmospheres, in particular, 2b showed no significant weight loss below 450°C.
Received: 28 January 1998/Accepted: 5 March 1998 相似文献
107.
Uenohara H. Tateno K. Kagawa T. Ohiso Y. Tsuda H. Kurokawa T. Amano C. 《Photonics Technology Letters, IEEE》1999,11(4):400-402
The polarization stability of 850-nm GaAs-based vertical-cavity surface-emitting lasers (VCSELs) under dynamic operation was investigated by comparing the characteristics of VCSELs grown on (311)B and (100) GaAs substrates. Significantly larger suppression ratios of the two orthogonal polarization modes was obtained for VCSELs on (311)B substrates than those on (100) substrates under zero-bias modulation. Time-dependent orthogonal polarization suppression ratio measurements also showed that the polarization direction was more stable in the VCSEL on (311)B substrates than that on (100) substrates. Error-free transmission was realized from VCSELs on (311)B substrates with and without a polarizer in both back-to-back and 100-m multimode fiber transmission 相似文献
108.
Damage monitoring of carbon fiber-reinforced plastics with Michelson interferometric fiber-optic sensors 总被引:1,自引:0,他引:1
This paper presents the application of a Michelson interferometric fiber-optic sensor for monitoring the damage of fiber-reinforced plastics. A Michelson interferometric fiber-optic sensor was mounted on the surface of unidirectionally aligned carbon fiber-reinforced epoxy composites. Response of the interference signal to either dynamic or static loading was investigated. Specimen being impacted, the optical interference signal dropped suddenly and then oscillated. The tensile test was performed with the measurement of optical interference signal, strain as well as acoustic emission. Both fast Fourier transform and digital filter processing of the optical interference signal were carried out to characterize the damage signal from the fiber-optic sensor. The optical interference signal whose frequency ranged from tens to hundreds Hz occurred when the specimen was damaged. It was shown that real-time information comparable to acoustic emission (AE) data could be obtained from Michelson interferometric fiber-optic sensor through a digital filtering technique. The Michelson interferometric fiber-optic sensor proved to be effective for monitoring the damage processes of the material studied. 相似文献
109.
Nakahara T. Tsuda H. Tateno K. Matsuo S. Kurokawa T. 《IEEE journal of selected topics in quantum electronics》1999,5(2):209-216
The fabrication procedure of smart pixels based on a hybrid integration of compound semiconductor photonic devices with silicon CMOS circuits is described. According to the 0.8-μm design rule, CMOS receiver/transmitter circuits are designed for use in vertical-cavity surface-emitting laser (VCSEL)-based smart pixels, and 16×16 and 2×2 Banyan-switch smart-pixel chips are also designed. By using our polyimide bonding technique, we integrated GaAs pin-photodiodes hybridly on the CMOS circuits. The photodetector (PD)/CMOS hybrid receiver operated error free at up to 800 Mb/s. Successful optical/optical (O/O) operation (a bit rate up to 311 Mbit/s) of the 2×2 Banyan-switch smart-pixel chip implemented with another VCSEL chip is also demonstrated 相似文献
110.
An AgI‐promoted meso–meso coupling reaction has been extended to prepare discrete 100 nm long linear arrays of porphyrins. Oxidation of the resulting phenyl end‐capped meso–meso linked porphyrins using a combination of 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) and ScIII(OTf)3 directly produces fully π‐conjugated fused porphyrin arrays (porphyrin tapes) of 10 nm molecular size. This research news article presents their synthesis, X‐ray crystal structures, and optical and electronic properties. Among these, the extremely small highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) optical gaps that reach into the infrared region suggest many applications of these compounds in materials science. 相似文献