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51.
The formation of solid solution in the Co3−xMnxO4 system in atmospheres of oxygen, air and argon was examined at a constant temperature of 1000 °C. In oxygen, a small amount
of the NaCl-type compound was found to co-exist with the cubic spinel in the composition rangex≤0.1. A single phase of the cubic spinel was found in the range 0.1 to 1.3 and the tetragonal spinel above 1.9. In the rangex=1.3 to 1.9 where the cubic and tetragonal spinels co-exist they both have very broadened diffraction line profiles. In air,
the identified phases and the changes in their lattice constants with composition were very similar to those in oxygen, except
that the NaCl-type compound and the cubic spinel co-existed over a larger range. In argon, the cubic spinel was not observed
over any of the composition range and the NaCI-type compound and the tetragonal spinel co-existed in the wide range of 1.1
to 2.3. The experimental results are discussed with regard to the cation distribution in the spinel and also to the relative
stability of Co3+- and Mn3+-ions under the low partial pressure of oxygen. 相似文献
52.
53.
In molecular biology, it is said that
two biological sequences tend to have similar properties if they have similar
three-dimensional structures. Hence, it is very important to find not only similar
sequences in the string sense, but also structurally similar sequences from
databases. In this paper we propose a new data structure that
is a generalization of a parameterized suffix tree (p-suffix tree for short)
introduced by Baker.
We call it the structural suffix tree or s-suffix tree for short.
The s-suffix tree can be used for finding structurally related patterns of RNA
or single-stranded DNA.
Furthermore, we propose an
O(n(log|| + log||)) on-line algorithm for constructing it,
where n is the sequence length,
|| is the size of the normal alphabet, and || is that of the
alphabet called parameter, which is related to the structure of the sequence.
Our algorithm achieves linear time when it is used to analyze RNA and DNA sequences.
Furthermore, as an algorithm for constructing the p-suffix tree,
it is the first on-line algorithm, though
the computing bound of our algorithm
is the same as that of Kosarajus best-known algorithm.
The results of computational experiments using actual RNA and
DNA sequences are also given to demonstrate our algorithms practicality. 相似文献
54.
Goldman ER Clapp AR Anderson GP Uyeda HT Mauro JM Medintz IL Mattoussi H 《Analytical chemistry》2004,76(3):684-688
Quantum dots (QDs) have the potential to simplify the performance of multiplexed analysis. In this work, we prepared bioinorganic conjugates made with highly luminescent semiconductor nanocrystals (CdSe-ZnS core-shell QDs) and antibodies to perform multiplexed fluoroimmunoassays. Sandwich immunoassays for the detection of cholera toxin, ricin, shiga-like toxin 1, and staphylococcal enterotoxin B were performed simultaneously in single wells of a microtiter plate. Initially the assay performance for the detection of each toxin was examined. We then demonstrated the simultaneous detection of the four toxins from a single sample probed with a mixture of all four QD-antibody reagents. Using a simple linear equation-based algorithm, it was possible to deconvolute the signal from mixed toxin samples, which allowed quantitation of all four toxins simultaneously. 相似文献
55.
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
56.
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
57.
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
58.
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
59.
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
60.
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