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81.
Naoki Takahashi Hiroshi Tujii Megumi Katori Kenji Yamashita Daiji Noda Tadashi Hattori 《Microsystem Technologies》2010,16(8-9):1303-1307
We have produced diffraction gratings for obtaining high resolution X-ray phase imaging, such as X-ray Talbot interferometer. These diffraction gratings were required to have a fine, high accuracy, high aspect ratio structure. Therefore, we decided to use the X-rays lithography technique that used synchrotron radiation of the directivity for a manufacture process. The accuracy of the completed structure depends largely on the accuracy of the X-ray mask. In our group, a resin material is conventionally used for the membrane of large X-ray masks. However, X-ray masks comprising a resin membrane have the disadvantage that, after several cycles of X-ray exposure, they crease and sag due to X-ray-derived heat. As a substitute for the conventional resin membrane, we experimentally fabricated a new X-ray mask using a carbon wafer membrane. The newly fabricated X-ray mask was subjected to X-ray exposure experiment. We succeeded in making the structure body which was almost shape. And the experimental results verified that the new mask did not deteriorate even when used repeatedly, demonstrating that it was highly durable. 相似文献
82.
Yoshitaka Sawa Kenji Yamashita Takeshi Kitadani Daiji Noda Tadashi Hattori 《Microsystem Technologies》2010,16(8-9):1369-1375
The nickel electroforming method using a high-concentration nickel sulfamate bath is commonly used to fabricate micro metal molds in the LIGA process; however, this method does not produce micro metal molds of sufficient hardness. One means of improving the hardness of micro metal molds made using the nickel electroforming method is to include additives in the nickel plating solution. Another method is nickel alloy plating or a similar technique. In this research, we used a nickel–boron (Ni–B) electroless alloy plating method to obtain a hard nickel plated film having hardness of 832 Hv. It was also ascertained that Ni–B electroless alloy plated film retains its high hardness even during heat treatment in conditions of 250°C for 1 h. To deal with the high stresses developed in high-hardness plated films, we proposed double-layer nickel electroforming. This method is covered and used on conventional nickel electroforming layer by high hardness micro mold. High hardness micro metal mold using double-layer was fabricated by nickel electroforming and Ni–B electroless alloy plating method. 相似文献
83.
In maintenance of concrete structures, crack detection is important for the inspection and diagnosis of concrete structures.
However, it is difficult to detect cracks automatically. In this paper, we propose a robust automatic crack-detection method
from noisy concrete surface images. The proposed method includes two preprocessing steps and two detection steps. The first
preprocessing step is a subtraction process using the median filter to remove slight variations like shadings from concrete
surface images; only an original image is used in the preprocessing. In the second preprocessing step, a multi-scale line
filter with the Hessian matrix is used both to emphasize cracks against blebs or stains and to adapt the width variation of
cracks. After the preprocessing, probabilistic relaxation is used to detect cracks coarsely and to prevent noises. It is unnecessary
to optimize any parameters in probabilistic relaxation. Finally, using the results from the relaxation process, a locally
adaptive thresholding is performed to detect cracks more finely. We evaluate robustness and accuracy of the proposed method
quantitatively using 60 actual noisy concrete surface images. 相似文献
84.
Kikuta K Tochigi N Saito S Shimoda T Morioka H Toyama Y Hosono A Suehara Y Beppu Y Kawai A Hirohashi S Kondo T 《Proteomics. Clinical applications》2010,4(5):560-567
Purpose : We aimed to identify novel chemotherapy responsiveness biomarkers for osteosarcoma (OS) by investigating the global protein expression profile of 12 biopsy samples from OS patients. Experimental design : Six patients were classified as good responders and six as poor responders, according to the Huvos grading system. The protein expression profiles obtained by 2‐D DIGE consisted of 2250 protein spots. Results : Among them, we identified 55 protein spots whose intensity was significantly different (Bonferroni adjusted p‐value<0.01) between the two patient groups. Mass spectrometric protein identification demonstrated that the 55 spots corresponded to 38 distinct gene products including peroxiredoxin 2 (PRDX 2). Use of a specific antibody against PRDX 2 confirmed the differential expression of PRDX 2 between good and poor responders, while PRDX 2 levels as measured by Western blotting correlated highly with their corresponding 2‐D DIGE values. The predictive value of PRDX 2 expression was further confirmed by examining an additional four OS cases using Western blotting. Conclusions and clinical relevance : These results establish PRDX 2 as a candidate for chemotherapy responsiveness marker in OS. Measuring PRDX 2 in biopsy samples before treatment may contribute to more effective management of OS. 相似文献
85.
Sarah Mostame Joonsuk Huh Christoph Kreisbeck Andrew J. Kerman Takatoshi Fujita Alexander Eisfeld Alán Aspuru-Guzik 《Quantum Information Processing》2017,16(2):44
With quantum computers being out of reach for now, quantum simulators are alternative devices for efficient and accurate simulation of problems that are challenging to tackle using conventional computers. Quantum simulators are classified into analog and digital, with the possibility of constructing “hybrid” simulators by combining both techniques. Here we focus on analog quantum simulators of open quantum systems and address the limit that they can beat classical computers. In particular, as an example, we discuss simulation of the chlorosome light-harvesting antenna from green sulfur bacteria with over 250 phonon modes coupled to each electronic state. Furthermore, we propose physical setups that can be used to reproduce the quantum dynamics of a standard and multiple-mode Holstein model. The proposed scheme is based on currently available technology of superconducting circuits consist of flux qubits and quantum oscillators. 相似文献
86.
An energy eigenvalue equation for a quasi-particle is derived, starting with the Heisenberg equation of motion for an annihilation operator. An elementary derivation of the Fermi liquid model having a sharply defined Fermi surface in thek-space is given, starting with a realistic model of a metal including the Coulomb interaction amongand between electrons and lattice-ions. The Ginzburg-Landau wave function
(r), where represents the superconducting pairon (Cooper-pair) state, is shown to be connected with the one-pairon density operatorn by
(r) = r¦n
1/2¦. A close analogy between supercurrent and laser is indicated.On sabbatical leave from Department of Physics and Astronomy, State University of New York at Buffalo, Buffalo, New York. 相似文献
87.
Satoru Maegawa Takao Mizusaki Yutaka Hirayoshi Tadashi Kusumoto Akira Hirai 《Journal of Low Temperature Physics》1980,39(1-2):151-171
Nuclear spin-lattice relaxation properties of hcp solid 3He with 4He impurities have been studied. At temperatures below the exchange plateau region, three kinds of relaxation time were observed. To analyze the data, a phenomenological four-bath model was developed, the four baths being the Zeeman bath, the phonon bath, an X-bath, and a Y-bath. The X-bath consists of the exchange bath and a part of the 4He-4He elastic interaction bath. The Y-bath is the main part of the elastic interaction bath. We measured the concentration dependence of the energy constants of all the baths, as well as the temperature and concentration dependences of the three kinds of relaxation time. The relaxation behavior corresponding to the process between the X-bath and the Y-bath could not be expressed by a single exponential function of time and the relaxation rate was strongly dependent on the concentration. This process may be related to the internal thermal equilibrium process within the elastic interaction bath. The impurity-dependent relaxation time between the X-bath and the phonon bath had a temperature dependence of T
–n with n = 7.4±0.3. 相似文献
88.
Humans and animals seek appropriate solutions to novel problems through trial-and-error (TE) actions and observation of their outcomes. Once an individual has obtained the knowledge (rule) to solve a problem, knowledge-based (KB) actions may be applied in a stereotypical manner. Solutions can thus be based on TE or KB actions. To characterize this learning process at the behavioral level, we developed a new cognitive task for a laboratory monkey (Macaca fuscata) to perform. In this task, a search array consisting of six elements of different colors was presented, one of which was the behaviorally relevant target. The target color was changed unpredictably with no instruction or signal, requiring the monkey to use a TE search strategy to find the target color. We found that once the monkey identified the relevant color by chance after a color change, correct performance increased in a step-like manner and at the same time, other response properties (reaction time and color-choice tendency) also changed discontinuously. These step-like alternations in behavioral performance may be attributed to the subject’s switching between TE and KB search strategies in the two phases. The present study has therefore provided behavioral evidence for the timing and manner of switching between search strategies during the process of updating knowledge. 相似文献
89.
In this study, a three-point bendJ lc fracture-toughness test was carried out using four types of structural steels at room temperature. The values of (γ p)V, which represent the width of the region where the voids are located just ahead of the crack tip, were measured by Beacham's method [9] with the help of a scanning electron microscope (SEM). The experimental (γ p) values and the theoretical values obtained using the finite element method (FEM) or calculated fromK at initiation are in good agreement. It was found that there is a certain linear relationship between (γ p)Vand the stretched zone width (SZW), and an experimental relationship betweenJ lc andσ flow·(γ p)V which may be expressed by the following equation: $$J_{lc} = 44.1 + 0.35\sigma _{{\text{flow}}} \cdot (\gamma _{\text{p}} )V_c KJ$$ whereσ flow is the average value of the yield stress and the ultimate tensile strength. (γ p)V c represents the critical value of (γ p)V. The numerical constant 44.1 kJ m?2 is considered to be aJ lc value for brittle fracture of the material tested, according to the authors' previous results. It is possible to calculateJ lc if (γ p)V c can be measured. 相似文献
90.
Increase in the amount of erythrocyte delta-aminolevulinic acid dehydratase in workers with moderate lead exposure 总被引:2,自引:0,他引:2
This report summarizes our current understanding of the heavy chain haplotypes found in our laboratories' rabbits. Independently derived data from several laboratories have been synthesizes into a consistent picture of the linked inheritance of allotypic markers found on the different heavy chain classes and subclasses of rabbit immunoglobulins in pedigreed rabbits, including the families of three apparent VH-CH recombinants. In one recombinant, the entire group of CH markers (C mu, C gamma, and C alpha) recombined with the set of VH. Although in the other two recombinants all CH markers may also have recombined as a group, in one of these only IgG and IgA CH genes were informative; in the other recombinant, only the IgG allotypes were informative. Some allotypic determinants found on IgM molecules ("conformational") appear only when a specific variable region allotype (VHa) is combined with a specific mu constant region allotype (C mu). New combinations of VHa and C mu allotypes were generated in two of the genetic recombinants and led to new "conformational" determinants. The gains and losses observed lend support to the hypothesis that the determinants result from conformations generated by the combination of allotype-specific VH and C mu protein sequences. Conceivably, DNA events that join VH to diversity (D)- and joining (J)-coding sequences or mRNA processing events that splice J to C mu could be involved in generating the sequences that form allotype-specific determinants. 相似文献