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71.
Tsuyoshi Honma Yasuhiko Benino Takumi Fujiwara Takayuki Komatsu Ryuji Sato 《Journal of the American Ceramic Society》2005,88(4):989-992
The glass formation region, crystalline phases, second harmonic (SH) generation, and Nd:yttrium aluminum garnet (YAG) laser-induced crystallization in the Sm2 O3 –Bi2 O3 –B2 O3 system were clarified. The crystalline phases of Bi4 B2 O9 , Bi3 B5 O12 , BiBO3 , Sm x Bi1− x BO3 , and SmB3 O6 were formed through the usual crystallization in an electric furnace. The crystallized glasses consisting of BiBO3 and Sm x Bi1− x BO3 showed SH generations. The formation of the nonlinear optical BiB3 O6 phase was not confirmed. The formation (writing) region of crystal lines consisting of Sm x Bi1− x BO3 by YAG laser irradiation was determined, in which Sm2 O3 contents were∼10 mol%. The present study demonstrates that Sm2 O3 –Bi2 O3 –B2 O3 glasses are promising materials for optical functional applications. 相似文献
72.
Several hexaaluminate-related materials were prepared via hydrolysis of alkoxide and powder mixing method for high temperature combustion of CH4 and C3H8, in order to investigate the effect of the concentration of the fuels, O2 and H2O on NOx emission and combustion characteristics. Among the hexaaluminate catalysts, Sr0.8La0.2MnAl11O19− prepared by the alkoxide method exhibited the highest activity for methane combustion and low NOx emission capability. NOx emission at 1500 °C was increased linearly with O2 concentration, whereas water vapor addition decreased NOx emission in CH4 combustion over the Sr0.8La0.2MnAl11O19− catalyst. In the catalytic combustion of C3H8 over the Sr0.8La0.2MnAl11O19− catalyst, the amount of NOx emitted was raised in the temperature range between 1000 and 1500 °C when the C3H8 concentration increased from 1 to 2 vol.%. It was found that NOx emission in this temperature range was reduced effectively by adding water vapor. 相似文献
73.
Takayuki Komatsu Kazuya Aida Tuyoshi Honma Yasuhiko Benino Ryuji Sato 《Journal of the American Ceramic Society》2002,85(1):193-199
The structural relaxation kinetics at the glass transition in tellurium oxide (TeO2 )-based glasses has been examined from viscosity and heat-capacity measurements to clarify the features of the structural relaxation in fragile oxide glass-forming liquids. A large decoupling between enthalpy relaxation and viscous flow, i.e., a large discrepancy between the activation energies for the enthalpy relaxation (recovery), Δ H , and viscous flow, E η , has been demonstrated in TeO2 -based glasses. The values in x K2 O· x MgO·(100 − 2 x )TeO2 glasses, for example, are ∼919–1051 kJ/mol for Δ H and ∼ 577–701 kJ/mol for E η , given the ratio of Δ H/E η ≈ 1.44–1.59. Some viscosity and heat-capacity data (all data have been reported previously) obtained from similar experiments in Sb2 O3 –B2 O3 glasses belonging to the category of strong glass-forming liquids have been reanalyzed in this paper for comparison; a strong coupling was found to exist between Δ H and E η , i.e., Δ H/E η ≈ 0.98–1.18. An origin of decoupling between Δ H and E η in fragile glass-forming systems such as TeO2 -based glasses has been discussed by considering the glass structure model for fragile glasses; strongly bonded correlated (highly constrained) regions are surrounded or connected by weakly bonded noncorrelated (unconstrained) parts. 相似文献
74.
基于无线传感器网络的分散目标跟踪:实际测试平台的开发应用(英文) 总被引:1,自引:0,他引:1
In the real world, centralized tracking in a largescale wireless sensor network (WSN) may not be feasible due to the possible
failure of fusion centre and the large communication delay in forwarding measurement data to the fusion centre. Distributed
target tracking techniques can be employed by tasking sensor nodes near to the target to perform sensing, target state
estimation and selection of future tasking sensor nodes. In this paper, the development and implementation of a prototype
ultrasonic WSN testbed to demonstrate distributed target tracking using the Extended Kalman Filter (EKF) algorithm is
described. In the testbed, a mobile robot is used to simulate the moving target, and static/mobile sensor nodes are deployed
to detect and track the target. The sensor nodes and robots are equipped with sonar and MICAZ to receive and process
instructions. Experimental evaluation of a number of sensor scheduling schemes are reported which shows the superior tracking
performance of our distributed competition based sensor scheduling scheme. 相似文献
75.
Theoretical and Experimental Insight into the Mechanism for Spontaneous Vertical Growth of ReS2 Nanosheets 下载免费PDF全文
Debjit Ghoshal Anthony Yoshimura Tushar Gupta Andrew House Swastik Basu Yanwen Chen Tianmeng Wang Yang Yang Wenjia Shou Jordan A. Hachtel Juan Carlos Idrobo Toh‐Ming Lu Sagnik Basuray Vincent Meunier Su‐Fei Shi Nikhil Koratkar 《Advanced functional materials》2018,28(30)
Rhenium disulfide (ReS2) differs fundamentally from other group‐VI transition metal dichalcogenides (TMDs) due to its low structural symmetry, which results in its optical and electrical anisotropy. Although vertical growth is observed in some TMDs under special growth conditions, vertical growth in ReS2 is very different in that it is highly spontaneous and substrate‐independent. In this study, the mechanism that underpins the thermodynamically favorable vertical growth mode of ReS2 is uncovered. It is found that the governing mechanism for ReS2 growth involves two distinct stages. In the first stage, ReS2 grows parallel to the growth substrate, consistent with conventional TMD growth. However, subsequent vertical growth is nucleated at points on the lattice where Re atoms are “pinched” together. At such sites, an additional Re atom binds with the cluster of pinched Re atoms, leaving an under‐coordinated S atom protruding out of the ReS2 plane. This under‐coordinated S is “reactive” and binds to free Re and S atoms, initiating growth in a direction perpendicular to the ReS2 surface. The utility of such vertical ReS2 arrays in applications where high surface‐to‐volume ratio and electric‐field enhancement are essential, such as surface enhanced Raman spectroscopy, field emission, and solar‐based disinfection of bacteria, is demonstrated. 相似文献
76.
The motor protein dynein was introduced into a nanotransport system. We oriented microtubules by their polarity, and immobilized them based on a dynein-microtubule gliding assay system. This system achieved unidirectional transport of kinesin-coated microbeads. In contrast to conventional kinesin-based orientation systems, the dynein-based system allowed the reverse motion of microtubules, resulting in an inversion of the orientation of microtubule polarity and thus reverse transport of kinesin-coated microbeads. This combined kinesin-?and dynein-based system constitutes a new means to facilitate the bidirectional orientation of microtubules and transport of cargos in a nanofluidic system. 相似文献
77.
The stress-induced voiding (SV) in Al-alloy films with stacked tungsten via structures was investigated. Voids were found in interconnections with stacked and borderless vias that had resistance increase after the aging tests. Failure occurs most frequently when the test structures are stored at approximately 250°C. This behavior can be explained by the diffusion creep model similar to SV in a flat line [1]. Finite-element simulations show that tensile stress in Al-lines between upper and lower plugs increases with temperature increase over 175°C. Al grains on W-plugs were found to have high-angle crystalline misorientation in transmission electron microscopy (TEM) observation. The tensile stress and grain misorientation should accelerate the void growth during high temperature storage. O2 plasma post metal etch treatment is effective to eliminate SV in stacked via structure. 相似文献
78.
Toshiyuki Nagata Kentaro Minami Masatatsu Yamamoto Tsubasa Hiraki Masashi Idogawa Katsumi Fujimoto Shun Kageyama Kazuhiro Tabata Kohichi Kawahara Kazuhiro Ueda Ryuji Ikeda Yukio Kato Masaaki Komatsu Akihide Tanimoto Tatsuhiko Furukawa Masami Sato 《International journal of molecular sciences》2021,22(21)
79.
Degradation of the global environment and depletion of resources are threatening sustainable development of mankind. In particular, climate change caused by increasing greenhouse gases is one of the most serious issues in analyzing energy systems. This paper aims at proposing frameworks to investigate sustainability and at evaluating technologies for sustainable energy systems. For this purpose, we first define the index of sustainable limits on resource depletion and emissions. Sustainability of mineral and energy resources is evaluated based on the index. Estimations indicate that energy resources and CO2 are unsustainable, and that we should introduce technologies to reduce energy consumption and CO2 emissions. Life cycle energy requirements are assessed for photovoltaic systems as representatives of the technologies. Through the life cycle assessment, we quantitatively evaluate measures to improve life cycle energy requirements and capital costs. At the same time, we clarify the direction of research and development required for technologies to realize sustainable energy systems. © 1999 Scripta Technica, Electr Eng Jpn, 130(2): 25–31, 2000 相似文献
80.
Mitsunobu Kawano Toshiaki Matsui Ryuji Kikuchi Hiroyuki Yoshida Toru Inagaki Koichi Eguchi 《Journal of power sources》2008
Direct internal and external reforming operations on Ni-samaria-doped ceria (SDC) anode with the practical size solid oxide fuel cell (SOFC) at intermediate temperatures from 600 to 750 °C are carried out to reveal the reforming activities and the electrochemical activities, being compared with the hydrogen-fueled power generation. The cell performance with direct internal and external steam reforming of methane and their limiting current densities were almost the same irrespective of the progress of reaction in the methane reformate at 700 and 750 °C. The durability test for 5.5 h at 750 °C with direct internal reforming operation confirmed that the cell performance did not deteriorate. The operation temperature of the cell controlled the reforming activities on the anode, and the large size electrode gave rise to high conversion due to the slow space velocity of the steam reforming. Direct internal steam reforming attained sufficient level of conversion for SOFC power generation with methane at 700 and 750 °C on the large Ni-SDC cermet anode. 相似文献