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131.
Cycle-closing product chain management with appropriate production site metabolism toward zero-emission in an industrial machinery corporation 总被引:2,自引:0,他引:2
Tohru?Morioka Noboru?YoshidaEmail author Yugo?Yamamoto 《Clean Technologies and Environmental Policy》2003,6(1):7-17
In the present study, an attempt is made to evaluate environmental efficiency through product chain and site metabolism management
in an industrial machinery corporation in Japan. Recent industrial ecology practice in manufacturing industry in Japan indicates
that environmentally transferred technology derived from product renovation is utilized in improving environmental performance
in process-oriented metabolism. From this viewpoint, inverse manufacturing and eco-industrial park strategy are applied in
the development concept of a demonstration site in an industrial machinery factory. As a result of the analysis using material
flow analysis and life cycle assessment, the following are clarified: firstly, design for disassembly reduced disassembly
time per unit of pump to 88%; secondly, a parts-reuse scenario gives great cost reduction up to 57% compared with a conventional
scenario; finally, carbon dioxide emission can be reduced to 14.5% of usual operation in the case study of facility management
with pump reuse and positive maintenance. 相似文献
132.
The switching time of a Cu(2)S-based gap-type atomic switch is investigated as a function of temperature, bias voltage, and initial off-resistance. The gap-type atomic switch is realized using a scanning tunneling microscope (STM), in which the formation and annihilation of a Cu-atom bridge in the vacuum gap between the Cu(2)S electrode and the Pt tip of the STM are controlled by a solid-electrochemical reaction. Increasing the temperature decreases the switching time exponentially with an activation energy of about 1.38 eV. Increasing the bias voltage also shortens the switching time exponentially, exhibiting a greater exponent for the lower bias than for the higher bias. Furthermore, faster switching has been achieved by decreasing the initial off-resistance between the Cu(2)S electrode and STM tip. On the basis of these results, we suggest that, in addition to the chemical reaction, the electric field in the vacuum gap plays a significant role in the operation of a gap-type atomic switch. This investigation advances our understanding of the operating mechanism of an atomic switch, which is a new concept for future electronic devices. 相似文献
133.
The hybrid input-output algorithm (HIO) used for phase retrieval is in many cases combined with the error-reduction algorithm (ER) to attempt to stabilize the HIO. However, in our previous paper [J. Opt. Soc. Am. A 16, 2163 (1999)], it was demonstrated that this combination makes it more likely that the resultant algorithm will fall into a periodic state before reaching a solution because the values of the input object outside the support, which is imposed as the object-domain constraint, are set to be zero in the intervals in which the ER is implemented. This paper deals with this problem inherent in the combination algorithm. The converging part of the HIO (CPHIO), which is an algorithm we previously developed [J. Opt. Soc. Am. A 15, 2849 (1998)], can be thought of as an extension of the ER for the case in which the input object can have nonzero values outside the support. Keeping this in mind, the algorithm is then constructed by combining the HIO with the CPHIO instead of with the ER. The computer simulation results that demonstrate the effectiveness of the proposed algorithm are given. 相似文献
134.
135.
A direct nanoflow liquid chromatography-tandem mass spectrometry system for interaction proteomics 总被引:11,自引:0,他引:11
Natsume T Yamauchi Y Nakayama H Shinkawa T Yanagida M Takahashi N Isobe T 《Analytical chemistry》2002,74(18):4725-4733
One of the strategies of functional proteomics, research aiming to discover gene function at the protein level, is the comprehensive analysis of protein-protein interactions related to the functional linkage among proteins and analysis of functional cellular machinery to better understand the basis of cell functions. Here, we describe the direct nanoflow LC (DNLC) system, which is equipped with a fritless high-resolution electrospray interface column packed with 1-microm reversed-phase (RP) beads and a novel splitless nanoflow gradient elution system to operate the column. Using RP-DNLC at an extremely slow flow rate, <50 nL/min, combined with data-dependent collision-induced dissociation tandem MS (MS/MS) and computer-assisted retrieval of spectra, we identified approximately 100 protein components in a biological complex such as a premature mammalian ribosome pull-down from cultured cells when we used an epitope-tagged protein as bait. Because this analysis is most sensitive, requires approximately 0.2 microg of total protein, and is a fully automated 1-h process, we anticipated that it should be an excellent tool for analyzing a limited amount of functional multi-protein complexes in cells. 相似文献
136.
Chihiro Mochizuki Hiroki Hara Ichiro Takano Tohru Hayakawa Mitsunobu Sato 《Materials science & engineering. C, Materials for biological applications》2013,33(2):951-958
The fabrication and characterization of a carbonate-containing apatite film deposited on a Ti plate via an aqueous spray method is described. The mist of the spray solution emitted from a perpendicularly oriented airbrush was made to strike a warmed Ti substrate. The thicknesses of the sprayed film and those heat-treated at 400 °C–700 °C under Ar gas flow were in the range 1.21–1.40 μm. The results of elemental analyses and Fourier transform infrared spectroscopy of the powders that were mechanically collected from the surface of the sprayed film suggest that the film was Ca10(PO4)6(CO3) · 2CO2 · 3H2O. The presence of the carbonate ion and the lattice CO2 molecule was confirmed via the aforementioned analyses; the finding was also consistent with the X-ray diffraction patterns of the films and the chemical identity of the sprayed and heat-treated films that were measured using X-ray photoelectron spectroscopy. The sprayed film comprises a characteristic network structure, which contains round particles within the networks, as was observed by field-emission scanning electron microscopy. A scratch test indicated that the shear stress of the sprayed film (21 MPa) significantly improved to 40 and > 133 MPa after heat-treatment at 600 °C and 700 °C, respectively, under Ar gas flow for 10 min. 相似文献
137.
Hiroki Nagai Tatsuya Suzuki Hiroki Hara Chihiro Mochizuki Ichiro Takano Tohru Honda Mitsunobu Sato 《Materials Chemistry and Physics》2012
A transparent p-type Cu2O thin film of 50 nm thickness was successfully fabricated by means of a solution-based process involving the thermal reaction of molecular precursor films spin-coated on a Na-free glass substrate. The precursor solution was prepared by the reaction of an isolated Cu2+ complex of ethylenediamine-N, N, N′, N′-tetraacetic acid with dibutylamine in ethanol. The Cu2O thin films resulting from heat treatment of the precursor film at 450 °C for 10 min in Ar gas at a flow rate of 1.0 L min−1 were characterized by X-ray diffraction which indicated a precise cubic lattice cell parameter of a = 0.4265(2) nm, with a crystallite size of 8(2) nm. X-ray photoelectron spectroscopy peaks, attributable to the O 1s and Cu 2p3/2 level of the Cu2O film were found at 532.6 eV and 932.4 eV, respectively. An average grain size of the deposited Cu2O particles of ca. 200 nm was observed via field-emission scanning electron microscopy. The optical band edge evaluated from the absorption spectrum of the Cu2O transparent thin film was 2.3 eV, assuming a direct-transition semiconductor. Hall Effect measurements of the thin film indicated that the single-phase Cu2O thin film is a typical p-type semiconductor, with a hole concentration of 1.7 × 1016 cm−3 and hole mobility of 4.8 cm2 V−1 s−1 at ambient temperature. The activation energy from the valence band to the acceptor level determined from an Arrhenius plot was 0.34 eV. The adhesion strength of the thin film on the Na-free glass substrate was also determined as a critical load (Lc1) of 2.0 N by means of a scratch test. The method described is the first example of fabrication and characterization of a p-type Cu2O transparent thin film by a wet process. 相似文献
138.
Jung-Lae Jo Keun-Soo Kim Tohru Sugahara Shijo Nagao Kyoko Hamasaki Masanobu Tsujimoto Katsuaki Suganuma 《Journal of Materials Science: Materials in Electronics》2013,24(8):3108-3115
Long term surface evolution of matte tin electroplating has been investigated under room temperature to understand the tin whisker mitigation by a trace amount of lead addition. No whisker growth has been observed on all the Sn–xPb samples (1 ≤ x ≤ 10 wt%), while at least 3 wt% of Pb addition is required to alter the columnar grain structure of pure Sn plating to equiaxed grains. The mitigation mechanism by such a trace amount of Pb is not caused by the grain texture control, but is due to the less inter-metallic composite (IMC) growth; the segregated Pb at the columnar grain boundaries disrupts the IMC growth, and releases Sn grain boundary migrations to relax the internal stress. This mechanism of stress relaxation and whisker growth suppression suggests that lead-free Sn plating without whisker growth can be realized by co-plating Sn with a Pb-like metal element that precipitates at the grain boundary to interfere with the IMC growth. 相似文献
139.
Masanobu Kamitakahara Eri Tatsukawa Yasuaki Shibata Shota Umemoto Taishi Yokoi Koji Ioku Tohru Ikeda 《Journal of materials science. Materials in medicine》2016,27(5):97
In addition to calcium phosphate-based ceramics, glass-based materials have been utilized as bone substitutes, and silicate in these materials has been suggested to contribute to their ability to stimulate bone repair. In this study, a silicate-containing α-tricalcium phosphate (α-TCP) ceramic was prepared using a wet chemical process. Porous granules composed of silicate-containing α-TCP, for which the starting composition had a molar ratio of 0.05 for Si/(P + Si), and silicate-free α-TCP were prepared and evaluated in vivo. When implanted into bone defects that were created in rat femurs, α-TCP ceramics either with or without silicate were biodegraded, generating a hybrid tissue composed of residual ceramic granules and newly formed bone, which had a tissue architecture similar to physiological trabecular structures, and aided regeneration of the bone defects. Supplementation with silicate significantly promoted osteogenesis and delayed biodegradation of α-TCP. These results suggest that silicate-containing α-TCP is advantageous for initial skeletal fixation and wound regeneration in bone repair. 相似文献
140.
Kenji Kawasaki Tomohiro Yoshida Hideo Yano Osamu Ishikawa Tohru Hata 《Journal of Low Temperature Physics》2002,126(1-2):229-234
We have studied superfluid
3
He in 0.8 m slab geometry by cw-NMR method. The static magnetic field for NMR was 22 mT and was perpendicularly applied to the surface. At pressures from 5 bar to 27 bar, we observed the negative shifts of NMR frequencies below the transition temperatures. Moreover we observed the fast order phase transition with the supercooling phenomena at lower temperatures, but NMR frequencies did not show a jump as they do at the A-B transition in the bulk liquid. Although the phase at low temperatures seemed to be B-phase, NMR frequencies still had the negative shifts. 相似文献