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排序方式: 共有3527条查询结果,搜索用时 15 毫秒
51.
Hiroyuki Koide Satoshi Hirano Takafumi Ide Kazuhiro Saito Hikaru Suzuki Go Yasuno Yoshitaka Hamashima Sei Yonezawa Naoto Oku Tomohiro Asai 《Advanced functional materials》2021,31(3):2005641
Protein affinity reagents (e.g., antibodies) are often used for basic research, diagnostics, separations, and disease therapy. Although a lot of “synthetic” protein affinity reagents have been developed as a cost-effective alternative to antibodies, their low biocompatibility is a considerable problem for clinical application. Lipid nanoparticles (LNP) represent a highly biocompatible drug delivery agent. However, little has been reported that LNP itself works as a protein affinity reagent in living animals. Here, LNP is engineered for binding to and neutralizing a target toxic peptide in living animals by multifunctionalization with amino acid derivatives. Multifunctionalized LNP (MF-LNP) is prepared using amino acid derivative-conjugated lipids. Optimized MF-LNP exhibits nanomolar affinity to the target toxic peptide and inhibits toxic peptide-dependent hemolysis and cytotoxicity. In addition, MF-LNP captures and neutralizes the toxic peptide after intravenous injection in the bloodstream; in addition, MF-LNP does not release the toxic peptide in the accumulated organ. These results reveal the potential of using LNP as a highly biocompatible protein affinity reagent such as an antidote. 相似文献
52.
Kunizo Ohkubo Teruo Saito Yuusuke Yamaguchi Yoshinori Tatematsu Jun Kasa Shin Kubo Takashi Shimozuma Kenji Tanaka Masaki Nishiura 《Journal of Infrared, Millimeter and Terahertz Waves》2017,38(7):853-873
We studied the transmission characteristics of hybrid modes in a corrugated circular waveguide above the Bragg frequency to develop a broad-band transmission line for millimeter waves. Millimeter waves at 294 GHz were transmitted into a straight waveguide. From observed power profiles in waveguide cross-sections, a high attenuation rate of 0.13 dB/m was obtained. To match a theoretical attenuation constant with the experimental one, we introduced an ad hoc coefficient of conventional surface reactance in the waveguide wall. This was necessary because the wall began to look like the surface with a decreasing anisotropic reactance owing to the frequency above the Bragg frequency. Using nonlinear optimization for mode content analysis, the observed power profiles in the waveguide cross-section were matched with theoretical profiles. There was good agreement between the calculated and observed centers of power profiles and attenuation rate along the waveguide. The theoretical analysis showed that the magnetic field at the waveguide wall increases and the substantial attenuation takes place. Above the Bragg frequency coupling to backwards propagating modes is a point of consideration. A combination of the backwards propagating EH1,26 and the forward propagating HE11 modes satisfied the Bragg condition at 294.7 GHz which was the nearest frequency of operating frequency. A strong attenuation of the incoming HE11 mode by Bragg resonance was not expected due to large difference of 0.7 GHz. It becomes clear that the observed high transmission loss outside of the Bragg resonance can be explained by a decrease in anisotropic surface reactance at the wall. 相似文献
53.
Ohtaki Y. Sengoku M. Sakurai K. Yamaguchi Y. Abe T. 《Electromagnetic Compatibility, IEEE Transactions on》1990,32(3):177-184
The radio propagation characteristics in groove-shaped roads surrounded by rough surface sidewalls are presented. Typical sidewalls are snowpack in heavy snow regions or buildings in urban areas. In this analysis, such roads are modeled by a straight groove waveguide with statistically rough sidewalls. A simple geometrical optical approach is applied to calculate the field strength along the longitudinal direction of the road as well as transversely across the road. The theoretical results are compared with previously presented experimental results. The theoretical results show that the surface roughness causes an additional propagation loss in regions far from the transmitting point and that the field strength in the cross section exhibits a cosine distribution with a slightly changing magnitude. These theoretical characteristics agree with the experimental results.<> 相似文献
54.
Miyake J. Maeda T. Nishimichi Y. Katsura J. Taniguchi T. Yamaguchi S. Edamatsu H. Watari S. Takagi Y. Tsuji K. Kuninobu S. Cox S. Duschatko D. MacGregor D. 《Solid-State Circuits, IEEE Journal of》1990,25(5):1199-1206
A 1-million transistor 64-b microprocessor has been fabricated using 0.8-μm double-metal CMOS technology. A 40-MIPS (million instructions per second) and 20-MFLOPS (million floating-point operations per second) peak performance at 40 MHz is realized by a self-clocked register file and two translation lookaside buffers (TLBs) with word-line transition detection circuits. The processor contains an integer unit based on the SPARC (scalable processor architecture) RISC (reduced instruction set computer) architecture, a floating-point unit (FPU) which executes IEEE-754 single- and double-precision floating-point operations a 6-KB three-way set-associative physical instruction cache, a 2-KB two-way set-associative physical data cache, a memory management unit that has two TLBs, and a bus control unit with an ECC (error-correcting code) circuit 相似文献
55.
Hori T. Otani A. Kaiho K. Yamaguchi I. Morita M. Yanabu S. 《Applied Superconductivity, IEEE Transactions on》2006,16(4):1999-2004
Using a high-temperature superconductor, we constructed and tested a model superconducting fault current limiter (SFCL). The superconductor and the vacuum interrupter as the commutation switch were connected in parallel using a bypass coil. When the fault current flows in this equipment, the superconductor is quenched and the current is transferred to the parallel coil because of the voltage drop in the superconductor. This large current in the parallel coil actuates the magnetic repulsion mechanism of the vacuum interrupter. Due to the opening of the vacuum interrupter, the current in the superconductor is broken. By using this equipment, the current flow time in the superconductor can be easily minimized. On the other hand, the fault current is also easily limited by large reactance of the parallel coil 相似文献
56.
Encapsulation of lead-free Sn/Zn/Bi solder alloy particles by coating with wax powder for improving oxidation resistance 总被引:2,自引:0,他引:2
Tomohiro Iwasaki Jeong Hwan Kim Shohei Mizuhashi Munetake Satoh 《Journal of Electronic Materials》2005,34(5):647-654
An encapsulation treatment of lead-free Sn/Zn/Bi solder powder was investigated for improving the oxidation resistance. Sn-8mass%Zn-3mass%Bi
alloy particles were coated with a wax (12-hydroxystearic acid) powder by means of a dry mechanical treatment method using
a ball mill. In order to determine the optimum operating conditions of the ball mill in the wax-coating treatments, the compressive
energy required for deforming a single Sn/Zn/Bi alloy particle was measured with an unconfined compression tester and the
mechanical energy applied to the alloy particles in the ball mill was estimated using the results of the compression test.
The optimum operating conditions were determined based on both the applied energy and the flowability of solder pastes, and
the wax-coated alloy particles maintaining the spherical shape were obtained under the conditions. The wettability test and
the solder balling test for the solder pastes containing the wax-coated alloy particles stored at room temperature in air
were carried out to evaluate the oxidation resistance performance. The wax-coated alloy particles had an excellent wettability
compared with the original alloy particles, and the oxidation resistance of the Sn/Zn/Bi solder powder was improved by the
encapsulation treatment. 相似文献
57.
Lu Yang Tomohiro Yendo Mehrdad Panahpour Tehrani Toshiaki Fujii Masayuki Tanimoto 《Journal of Visual Communication and Image Representation》2010,21(5-6):542-560
In this paper, we present a new view synthesis method in multiview camera configurations of Free viewpoint TV (FTV) where potential depth errors are considered. The emphasis is on the artifacts eliminating for photorealistic synthesis especially near object boundaries. In contrast to conventional techniques which ignore geometry errors, we first categorize the artifact cases and depth modes. Furthermore, this paper infers the complementarity principle of the artifacts from left and right references. This complementarity guarantees the effectiveness of our reliability-based synthesis. The reliability reasoning is crucial for artifacts reduction. The reliable and unreliable areas from different views can be correctly labeled. Then artifacts caused by unreliable pixels from one reference can be replaced by the reliable pixels from the other reference. As a final result, artifacts of novel view are demonstrated to be significantly reduced on different multiview sequences. 相似文献
58.
A simple, novel structure for MOSFETs with channels 300–500 nm long is proposed and evaluated by means of two-dimensional numerical analysis. The new device is constructed of a silicide-on-lightly-doped-drain (SOLID) structure. In this structure, the silicide layers assure lower parasitic source/drain resistances. Moreover, distinct segregation phenomena, i.e., formation of a highly concentrated, thin (10 nm) layer at the source/drain-silicide interface, perform an important role in achieving good ohmic contact. With the SOLID structure, most of the N+ drain region, which occupies a large portion of the conventional profile-drain structure and is superfluous for lowering high drain field, canbe replaced by an N? region. This results is improved breakdown voltage characteristics with significant mitigation of current gain reduction. The features of the SOLID structure are also compared with those of conventional profile-drain structures, i.e. double diffused drain (DDD) and lightly doped drain (LDD) structures. 相似文献
59.
An optical polarisation control scheme utilising optical heterodyne detection for coherent transmission is proposed and demonstrated at a wavelength of 1.5 ?m. It converts an arbitrary polarisation state to a linear state at a received optical power level of less than ?70 dBm. 相似文献
60.
Low-threshold and high temperature single-longitudinal-mode operation of 1.55 ?m-band DFB-DC-PBH LDs
1.55 ?m-band distributed-feedback laser diodes with double-channel planar buried heterostructure (DFB-DC-PBH LDs) have been developed. As well as low threshold current, 19 mA at room temperature, stable CW single-longitudinal-mode operation up to the high power level of 23 mW and the high temperature of 108°C has been obtained. 相似文献