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71.
K. Hamaguchi Y. Maeda H. Matsumoto M. Nishiuchi H. Tomida K. Koyama H. Awaki T. G. Tsuru 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2000,450(2-3):360-364
We have developed a CCD calibration system using fluorescent X-ray lines with energies ranging from 1.49 keV (Al K) to 11.2 keV (Se K). The absolute X-ray flux is calibrated by a gas proportional counter, while the emerging spectra are monitored by solid-state silicon detectors. In order to suppress contaminating X-rays in the fluorescence spectra, mechanical collimators were set in the X-ray beam line, high-purity targets for fluorescent lines were used, and band-pass filters were put on the X-ray beam line. As for the purity of the fluorescent X-rays, the typical purity achieved was 98%. 相似文献
72.
Deokho Lee Yohei Tomita Yukihiro Miwa Heonuk Jeong Ari Shinojima Norimitsu Ban Shintaro Yamaguchi Ken Nishioka Kazuno Negishi Jun Yoshino Toshihide Kurihara 《International journal of molecular sciences》2022,23(23)
Cardiovascular abnormality-mediated retinal ischemia causes severe visual impairment. Retinal ischemia is involved in enormous pathological processes including oxidative stress, reactive gliosis, and retinal functional deficits. Thus, maintaining retinal function by modulating those pathological processes may prevent or protect against vision loss. Over the decades, nicotinamide mononucleotide (NMN), a crucial nicotinamide adenine dinucleotide (NAD+) intermediate, has been nominated as a promising therapeutic target in retinal diseases. Nonetheless, a protective effect of NMN has not been examined in cardiovascular diseases-induced retinal ischemia. In our study, we aimed to investigate its promising effect of NMN in the ischemic retina of a murine model of carotid artery occlusion. After surgical unilateral common carotid artery occlusion (UCCAO) in adult male C57BL/6 mice, NMN (500 mg/kg/day) was intraperitoneally injected to mice every day until the end of experiments. Electroretinography and biomolecular assays were utilized to measure ocular functional and further molecular alterations in the retina. We found that UCCAO-induced retinal dysfunction was suppressed, pathological gliosis was reduced, retinal NAD+ levels were preserved, and the expression of an antioxidant molecule (nuclear factor erythroid-2-related factor 2; Nrf2) was upregulated by consecutive administration of NMN. Our present outcomes first suggest a promising NMN therapy for the suppression of cardiovascular diseases-mediated retinal ischemic dysfunction. 相似文献
73.
日本是一个地震多发的国家,而特殊的地形又决定了水坝在其经济社会发展中具有重要的地位,因此水坝的安全管理和地震安全评价就成为一个至关重要的方面. 相似文献
74.
75.
Norihiro Moriyama Kenji Haraya Hiroki Nagasawa Masakoto Kanezashi Toshinori Tsuru 《American Institute of Chemical Engineers》2020,66(7):e16250
Permeance and permeance ratio in binary separation generally are obtained from experimental data using an analytical permeance equation consisting of the logarithmic average of the partial pressure difference (hereafter, approximate permeance equation). The aim of the present study was to clarify the applicable range for this equation. First, the separation performance of a membrane module was calculated with various given membrane properties (permeance, permeance ratio) and operation conditions (pressure, flow rate) via numerical computation. The obtained concentrations and flow rates in the retentate and permeate were used to calculate permeances via approximate permeance equation, and the validity was discussed by comparing permeances used for numerical computation with obtained ones. The present work clarifies the validity of the approximate permeance equation, and yields a general guideline stipulating that the partial pressure difference across the membrane at the inlet and outlet should maintain more than 60% to obtain the correct permeance. 相似文献
76.
Xin Yu Lie Meng Hiroki Nagasawa Masakoto Kanezashi Masato Machida Toshinori Tsuru 《Journal of the American Ceramic Society》2019,102(11):6946-6956
The decomposition of sulfur trioxide to produce sulfur dioxide and oxygen using a catalytic membrane reactor is technology that promises to improve the economic viability of the thermochemical water-splitting Iodine-Sulfur (IS) process for large-scale CO2-free hydrogen production. The chemical stability of membrane materials under SO3, however, is a significant challenge for this strategy. In this study, microporous membranes with a layered structure that consisted of a membrane support prepared from α-Al2O3, an intermediate layer prepared from silica-zirconia, and a top layer prepared from bis (triethoxysilyl)ethane-derived organosilica sols, were examined for stability under SO3 and for use in SO3/O2 separation. An α-Al2O3 support that features SiO2–ZrO2 intermediate layers with large pore sizes and a high Si/Zr molar ratio showed excellent resistance to SO3, which was confirmed by N2 adsorption, Energy Dispersive X-ray Spectroscopy (EDS), and Scanning Electron Microscopy (SEM). These membranes also demonstrated a negligible change in gas permeance before and after SO3 exposure. Subsequently, in binary-component gas separation at 550°C, microporous organosilica-derived membranes achieved an O2/SO3 selectivity of 10 (much higher than the Knudsen selectivity of 1.6) while maintaining a high O2 permeance of 2.5 × 10−8 mol m–2 s–1 Pa–1. 相似文献
77.
We show that anyk-connected graphG = (V, E) has a sparsek-connected spanning subgraphG′ = (V, E′) with ¦E′¦ =O(k¦V¦) by presenting anO(¦E¦)-time algorithm to find one such subgraph, where connectivity stands for either edge-connectivity or node-connectivity. By using this algorithm as preprocessing, the time complexities of some graph problems related to connectivity can be improved. For example, the current best time boundO(max{k 2¦V¦1/2,k¦V¦}¦E¦) to determine whether node-connectivityK(G) of a graphG = (V, E) is larger than a given integerk or not can be reduced toO(max{k 3¦V¦3/2,k 2¦V¦2}). 相似文献
78.
79.
Tatsuo Inoue Toshihide Igari Fusahito Yoshida Akihiko Suzuki Sumio Murakami 《Nuclear Engineering and Design》1985,90(3):287-297
Some of the interim results of the Bench Mark Project by the Subcommittee on the Inelastic Analysis and Life Prediction of High Temperature Materials, JSMS, is presented. The purpose of the present bench mark study is to review and evaluate the inelastic constitutive models relevant to material response under the plasticity-creep interaction.By specifying normalized and tempered steel at 600°C, sixteen bench mark problems of four categories are first established: (I) tensile stress-strain relations and creep curves, (II) material response under mixed modes of plastic and creep loading, (III) ratcheting and deformation under program loads, and (IV) cyclic deformation behaviour under the combination of different strain rates. Then, the outline of seventeen inelastic constitutive models of nine types discussed in this project is presented. Finally, the interim results of these bench mark tests are compared with the corresponding predictions of the constitutive models to evaluate their accuracy in simulating the actual behaviour of the material. 相似文献
80.
Yoshinori Kitatsuji Masato Tsuru Tetsuya Takine Yuji Oie 《Telecommunication Systems》2008,37(1-3):97-108
In traffic engineering (TE), it is vital to take traffic characteristics of the flows into account in appropriately assigning the flows to multiple network paths to achieve better delay performance as a whole in order to effectively distribute traffic flows over the paths. This paper presents a novel traffic characteristic-aware flow assignment method to reduce the queuing delay in a fundamental case where two types of flows with distinct traffic characteristics (e.g., burstiness) are distributed into two paths. First, we extensively analyze the queuing delays in assigning flows in the manner of various combinations of flows in terms of minimizing the worst queuing delay among two paths and show that it is not easy to find the optimal flow assignment when the paths have different bandwidths. Second, we propose an on-line flow assignment method for the different-bandwidth paths and show that the numerical simulation with the method finds a nearly optimal flow assignment and outperforms up to 40% compared with the conventional path-bandwidth-based flow assignment. Our evaluation suggests that considering the traffic characteristics in the flow distribution over multiple paths significantly improves the delay performance when the flows have distinct characteristics. 相似文献