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91.
The local structures of Cl- and Br- in an anion-exchange resin have been investigated by X-ray absorption fine structure (XAFS). The resins, which have been equilibrated under various partial water vapor pressures to allow the anions to have various hydration numbers, are provided for XAFS measurements. The XAFS spectra indicate that two scattering groups around the counteranion are present, that is, water molecules and an ion-exchange group. Regression analyses allow the separation of the contributions from these two scattering groups; thus, the average hydration number (N) is determined. The hydration number linearly increases with increasing the number of water molecules (n) adsorbed by an ion-exchange pair (an ion-exchange group and a counteranion) until the ion-exchange pair adsorbs ca. 3 water molecules, indicating that all of the adsorbed water molecules coordinate the counteranion. However, an increase in N with increasing n becomes small as n exceeds 3; N finally reaches 3.9 (+/-0.4) for Cl- and ca. 3.4 (+/-0.5) for Br-. Detailed studies of the water adsorption isotherms imply that the maximum hydration number of these anions is three when they are bound by the ion-exchange groups, and as more water molecules are supplied, they are dissociated from the ion-exchange groups; ca. 40% of total counteranions are dissociated from the ion-exchange groups. 相似文献
92.
Wind flows over the 8.2-m Subaru Telescope at Mauna Kea in Hawaii were analyzed with a correlation method. Three or four wind flows were detected from our measurements. Spatial and temporal resolution of the wind-flow analysis across the 8.2 m pupil were investigated experimentally. A three-dimensional spatiotemporal-frequency analysis was also applied to the wind-flow data. 相似文献
93.
T. Shin-ike T. Sakai Tetsuo Sakai G. Adachi J. Shiokawa 《Materials Research Bulletin》1977,12(7):685-688
The nature of the V/1bO/1bV interaction of the perovskite type rare-earth vanadites were studied by spectroscopic methods. Infrared and ultraviolet analyses revealed that the V/1bO bond length became shorter and that the V/1bO bond strength increased, as a function of the atomic number of lanthanide elements in LnVO3. Judging from the x-ray fluorescent spectra of oxygen-Kα, the energy level of O2? (pπ) orbitals of the heavier rare-earth vanadites was lower than that of the lighter rare-earth vanadites. 相似文献
94.
Pulsed laser irradiation impact on two marine diatoms Skeletonema costatum and Chaetoceros gracilis 总被引:2,自引:0,他引:2
The ability of pulsed laser irradiations to cause damage on the biofouling organisms is recently being investigated. If this technique is employed in industries such as power generation wherein a large quantity of water is being used for the cooling purpose, many organisms other than the targeted would get affected. In this study, we have investigated the damage caused by the pulsed laser irradiations from an Nd:YAG laser (fluence 0.1J/cm(2)) for varying durations such as 2, 5, 10, 30, 60 and 300 s on two marine diatom species namely Skeletonema costatum and Chaetoceros gracilis. Upon exposure to low power laser irradiations, these diatom species showed mortalities between 52.6+/-9.3% to 97.7+/-3.1% in the case of S. costatum and 57.8+/-2.5% to 98.9+/-0.6% in the case of C. gracilis for 2 and 300 s of irradiations, respectively. The mortality increased with the increase in the duration of laser irradiation. The estimation of the chlorophyll a concentration in the irradiated samples showed a considerable reduction varying between 9.8% and 57% in C. gracilis and 3% and 70.3% in S. costatum for 2 and 300 s of irradiations, respectively. The laser-survived cells grew as the non-irradiated (control) samples. C. gracilis frustules were broken by the laser whilst, the cell materials were drained out of the frustules in the case of S. costatum. The study therefore showed that the low power pulsed laser irradiations could cause significant damage on the two species of planktonic diatoms. 相似文献
95.
Fujimoto J Umeda Y Tamura T Tomiyama T Kimura F 《Environmental science & technology》2003,37(23):5398-5406
To achieve sustainability, resource consumption and waste generation must be drastically decreased. For societal acceptance, preservation of both quality of life and corporate profits are essential. One promising approach is to shift the source of value from the amount of product sold to the quality of services the product provides. This paper describes the need for redesigning recycling systems from a manufacturing perspective and then discusses the possibility of this "servicification" of products, describing our experience with prototype development. We discuss development of product prototypes and their business, using consumer facsimile machines as an example of "service-oriented products". Traditional thought presumes that only products comprising new materials and components are valuable. Consideration of a service-oriented product can serve as a stimulus to revise this mode of thought and to control delivery and quality of disposed products. This paper also provides a life cycle simulation of the developed service-oriented business. Simulation results indicate that service-oriented business can potentially reduce environmental impact while extending business opportunities from the viewpoint of whole product life cycles. 相似文献
96.
Characterization of the chemical conversion films that form on Mg−Al alloy in colloidal silica solution 总被引:1,自引:0,他引:1
Seong?-Jong?KimEmail author Ying?Zhou Ryoichi?Ichino Masazumi?Okido Shoji?Tanikawa 《Metals and Materials International》2003,9(2):207-213
Chemical conversion treatment of Mg−Al alloy (AZ91) using colloidal silica as an alternative to chromate conversion was investigated
as a function of solution pH, temperature, solution conditions, and treatment time. The solution used for the colloidal silica
coating consisted of colloidal silica, titanium sulfate, and cobalt ions to maintain good anti-corrosion and adhesion properties.
Adding CoSO4 to the colloidal silica solution enhanced the adhesion force between the silica film and magnesium substrate. The optimum
conditions for the chemical conversion treatment solution were pH 2, 90-sec treatment, and 25°C. 相似文献
97.
Thiamine is presently one of the most attractive substrates used for sensitive fluorometric measurements of peroxides. Thiochrome (TC), a highly fluorescent product, is formed in enzyme-mediated oxidations. It is assumed that H(2)O(2) is nearly quantitatively converted to TC. The reaction cannot differentiate H(2)O(2) from many other peroxides such as methylhydroperoxide (MHP); to perform differential measurements, H(2)O(2) can first be selectively destroyed by a suitable catalyst such as MnO(2). In substituting Ag(2)O for MnO(2) to accomplish the selective destruction of H(2)O(2), we achieved the stated objective but were puzzled by a 3-fold increase in the MHP response in the presence of Ag(2)O. It was soon discovered that traces of dissolved Ag(+) and Hg(2+) can dramatically increase the yield of TC in this reaction from either H(2)O(2) or MHP; the normal yield in fact is only 20%. We present here a reaction scheme and kinetic model that adequately describes this behavior and should provide a path to substantially increase the sensitivity of this important assay method. 相似文献
98.
Fast agglomerative hierarchical clustering algorithm using Locality-Sensitive Hashing 总被引:1,自引:6,他引:1
Hisashi Koga Tetsuo Ishibashi Toshinori Watanabe 《Knowledge and Information Systems》2007,12(1):25-53
The single linkage method is a fundamental agglomerative hierarchical clustering algorithm. This algorithm regards each point
as a single cluster initially. In the agglomeration step, it connects a pair of clusters such that the distance between the
nearest members is the shortest. This step is repeated until only one cluster remains. The single linkage method can efficiently
detect clusters in arbitrary shapes. However, a drawback of this method is a large time complexity of O(n
2), where n represents the number of data points. This time complexity makes this method infeasible for large data. This paper proposes
a fast approximation algorithm for the single linkage method. Our algorithm reduces the time complexity to O(nB) by rapidly finding the near clusters to be connected by Locality-Sensitive Hashing, a fast algorithm for the approximate
nearest neighbor search. Here, B represents the maximum number of points going into a single hash entry and it practically diminishes to a small constant
as compared to n for sufficiently large hash tables. Experimentally, we show that (1) the proposed algorithm obtains clustering results similar
to those obtained by the single linkage method and (2) it runs faster for large data than the single linkage method.
Hisashi Koga received the M.S. and Ph.D. degree in information science in 1995 and 2002, respectively, from the University of Tokyo. From
1995 to 2003, he worked as a researcher at Fujitsu Laboratories Ltd. Since 2003, he has been a faculty member at the University
of Electro-Communications, Tokyo (Japan). Currently, he is an associate professor at the Graduate School of Information Systems,
University of Electro-Communications. His research interest includes various kinds of algorithms such as clustering algorithms,
on-line algorithms, and algorithms in network communications.
Tetsuo Ishibashi received the M.E. degree in information systems design from the Graduate School of Information Systems at the University
of Electro-Communications in 2004. Presently, he is a system engineer at Fujitsu Broad Solution & Consulting Inc.
Toshinori Watanabe received the B.E. degree in aeronautical engineering in 1971 and the D.E. degree in 1985, both from the University of Tokyo.
In 1971, he worked at Hitachi as a researcher in the field of information systems design. His experience includes demand forecasting,
inventory and production management, VLSI design automation, knowledge-based nonlinear optimizer, and a case-based evolutionary
learning system nicknamed TAMPOPO. He also engaged in FGCS (Fifth Generation Computer System) project of Japan and developed
a new hierarchical message-passing parallel cooperative VLSI layout problem solver that ran on PIM (Parallel Inference Machine)
in 1991. Since 1992, he has been a professor at the Graduate School of Information Systems, University of Electro-Communications,
Tokyo, Japan. His areas of interest include media analysis, learning intelligence, and the semantics of information systems.
He is a member of the IEEE. 相似文献
99.
A service provisioning system for distributed personalization with private data protection 总被引:1,自引:0,他引:1
Personalized services can provide significant user benefits since they adapt their behavior to better support the user. Personalized services use a variety of data related to the user to decide their behavior. Thus personalized service needs a provisioning system that can collect the data that impacts service behavior and allows selection of the most appropriate service. However, in the coming ubiquitous environment, some data necessary for determining service behavior might be unavailable due to two possible reasons. One is that the data does not exit. The other is that the data exists but cannot be accessed. For example, users do not want to disclose their personal information, and service providers do not also want to expose data related to their knowhow in services. This paper describes a new service provisioning system for distributed personalization with private data protection. Specifically, the system selects applicable services by assessing how well each candidate service behaves when some data is missing. It then executes those selected services while hiding the users’ and providers’ private data in a distributed manner. We first summarize the requirements for a personalized service system, and introduce our fundamental policies for the system. The two main components of our system are then described in detail. One component is a service assessment mechanism that can judge if a service can work without data that can be used for adaptation. The second component is a service execution mechanism that can utilize private data while still ensuring privacy. This component divides service logic and executes divided logic where necessary data is available. The paper finally describes our prototype implementation and its performance evaluation results. 相似文献
100.
Fu-Ying Huang Satoshi Yamamoto Eric Baugh Tetsuo Semba 《Microsystem Technologies》2007,13(8-10):849-857
A new approach to analyze HDD seeking acoustics is proposed. An acoustic transfer function was derived that has seeking current as input and seeking acoustics as response. The derivation and the advantage and limitation of this acoustic transfer function approach is discussed in details in this paper. HDD seeking acoustics is mainly determined by the seeking current spectrum and the mechanical design. The acoustics transfer function represents the mechanical design, and was used to diagnose trouble mechanical modes and to guide servo design to reduce specific seeking current frequency content. The acoustic transfer function approach also enables quick performance prediction of combination of different mechanical designs and seeking currents. Various HDDs with different seeking current profiles and mechanical designs were evaluated experimentally and numerically. Finally, a new seeking servo algorithm was evaluated, and good agreement was shown between the numerical prediction using the acoustics transfer function approach and the measured seeking acoustics. 相似文献