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排序方式: 共有452条查询结果,搜索用时 15 毫秒
51.
Chen Zhong Katsuhiko Saito Kazuaki Kawaguchi Hiroshi Setoue 《Packaging Technology and Science》2014,27(7):509-520
To verify the cushion performance of transport packaging, two traditional drop test methods – free fall and controlled shock tests – and a traditional simulation method are often used. However, it is difficult to assure the safety of a test product when the traditional drop test method is applied, and results from the traditional simulation method are not sufficiently accurate to be used to test packaging material. Therefore, we propose a new test method called ‘the hybrid drop test’ by integrating the traditional drop test and simulation methods. The hybrid drop test ensures the safety of the test product and improves test efficiency. The results of the verification test show that this new drop test method can be applied to test the cushion performance of pulp mould transport packaging. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
52.
53.
Exposure to cosmic radiation in operation of a jet aircraft is considered to be a part of the occupational exposure. Cosmic radiation doses received in aviation are generally evaluated by numerical model simulations. The precision of the model calculation should be verified by measurements. From the viewpoint of radiological protection, neutrons are the most contributing radiation component and have to be precisely measured. Neutron measurements were thus performed in a long-haul flight using a relatively new transportable neutron monitor (WENDI-II) which responds fairly well to the cosmic-ray neutrons. The in-flight measurement was carried out on 5-6 November 2009 on a polar route flight from New York/John F. Kennedy airport to Seoul/Incheon airport. The flying time was ~14 h. The observations obtained as 1 cm ambient dose equivalent were compared with model calculations using a computer program developed by the authors for the calculation of aviation route doses 'JISCARD EX'. Good agreements between the measured and calculated values were observed over the polar route where the geomagnetic cut-off rigidity is the lowest. 相似文献
54.
A particulate Al-30 wt pct TiC composite was employed as a grain refiner for the Al-4.5 wt pct Cu alloy. The composite contains
submicron TiC particles. The addition of the TiC grain refiner to the metal alloy in the amount of 0.1 Ti wt pct effected
a remarkable reduction in the average grain size in Al-4.5 wt pct Cu alloy castings. With the content of over 0.2 Ti wt pct,
the grain refiner maintained its refining effectiveness even after a 3600-second holding time at 973 K. The TiC particles
in the resulting castings were free of interfacial phases. It is concluded that the TiC are the nucleating agents and that
they are resistant to the “fading effect” encountered with most grain refiners. 相似文献
55.
YANG Changping ZHOU Zhihui WANG Hao HU Jifan IWASA Kazuaki SUGAWARA Hitoshi SATO Hideyuki 《稀有金属(英文版)》2006,25(Z1)
Elastic neutron diffraction measurements were performed on single crystals to study the ground state below the mysterious exotic transition temperature 0.86 K. An antiferromagnetic order with a tiny moment of 0.027μB per formula is formedas the ground state for CeOs4Sb12 below the transition point. Our neutron data gives the evidence of spin density wave state for CeOs4Sb12 in this work. 相似文献
56.
Recently,a number of environmental problems caused from fossil fuel combustion have been focused on.Inaddition,with the eventual depletion of fossil energy resources,hydrogen gas is expected to be an alternativeenergy resource in the near future.It is characterized by high energy per unit weight,high reaction rate,widerange of flammability and the low emission property.On the other hand,many researches have been underway inseveral countries to improve a propulsion system for an advanced aircraft.The system is required to have higherpower,lighter weight and lower emissions than existing ones.In such a future propulsion system,hydrogen gaswould be one of the promising fuels for realizing the requirements.Considering these backgrounds,our group hasproposed a new cycle concept for hydrogen-fueled aircraft propulsion system.In the present study,we perform 3dimensional computations of turbulent flow fields with hydrogen-fueled combustion around a turbine blade.Themain objective is to clarify the influence of arrangement of hydrogen injector holes.Changing the chordwise andspanwise spacings of the holes,the 3 dimensional nature of the flow and thermal fields is numerically studied. 相似文献
57.
We examined thein vitro surface activity, immersional wettability and adhesional wettability shown by aqueous solutions of soy lysophospholipid (SLP)/monoglyceride
(MG)/fatty acid (FA), SLP/FA and SLP/MG, and found that many lipid mixtures showed significant surface activity when their
MG and FA components consisted of polyunsaturated FA and/or medium chain FA. The more unsaturated the FA, the higher the surface
activity. A mixture of SLP/medium chain fatty acid MG (medium chain MG)/medium chain FA showed the highest surface activity,
and was comparable to an Aerosol-OT surfactant, the most effective wetting agent. SLP/polyunsaturated FA monoglyceride (polyunsaturated
MG)/polyunsaturated FA, SLP/medium chain FA, and SLP/polyunsaturated FA, SLP/medium chain MG, and SLP/polyunsaturated MG also
showed a high degree of activity. Wettability decreased rapidly when the amount of saturated, long chain FA moieties increased.
It is recognized that the degrees of unsaturation and the chain length of FAs in the lipid mixtures have a decisive influence
on surface activities. Higher ratios of MG and FA to SLP gave higher activity; and solubilizers such as bile salts were necessary
to dissolve them in water. 相似文献
58.
This paper describes external reference management and distributed unification in a distributed implementation of a concurrent logic programming language KL1. This implementation is based on the KLIC system. KLIC has a feature calledgeneric objects that enable easy modification and extension of the system without changes in the core implementation. This distributed implementation is built upon the same core and external references are represented using generic objects. Unification operations are defined as methods of generic objects. Since creation of interprocessor reference loops cannot be avoided, we studied a new unification scheme that can cope with interprocessor reference loops. We built several experimental distributed systems that all demonstrate reasonable efficiency. 相似文献
59.
Takayuki Sawada Yuji Yamagata Kazuaki Imai Kazuhiko Suzuki 《Journal of Electronic Materials》1996,25(2):245-251
Interface properties of MBE-grown ZnSe/GaAs substrate systems formed on variously pretreated GaAs surfaces, which include
standard chemically etched (5H2SO4:1H2O2: 1H2O), (NH4)2Sx-, NH4I-, and HF-pretreated surfaces, are investigated by capacitance-voltage (C-V) and deep level transient spectroscopy (DLTS)
measurements. A HF-pretreated and annealed ZnSe/p-GaAs sample showed marked reduction of interface state density, Nss, with Nss,min below 4 x 1011cm-2 eV-1 near Ec- EFS= 1.0 eV. The value is about one order of magnitude smaller than that of the standard chemically etched interface, and comparable
to (NH4)2Sx- pretreated interface. Nevertheless, C-V characteristics of ZnSe/nGaAs samples, which were measured for the first time, indicate
that interface Fermi level, EFS, is not completely unpinned due to the interface states located above the midgap. A consistent result was obtained by DLTS
method in determining EFS position. The influence of Nss distribution on vertical current conduction is also analyzed. It is found that U-shaped interface states with Nss(E) > 1 x 1013 cm-2 eV-1 above the midgap may cause an excess voltage drop larger than a few volts at the interface. 相似文献
60.
Takayuki Tomaru Shinji Miyoki Masatake Ohashi Kazuaki Kuroda Takashi Uchiyama Toshikazu Suzuki Akira Yamamoto Takakazu Shintomi Akitoshi Ueda Daisuke Tatsumi Shuichi Sato Koji Arai Masaki Ando Koji Watanabe Kenji Nakamura Masahiko Watanabe Kazuhiko Ito Izumi Kataoka Hiroaki Yamamoto Brett Bochner Yaron Hefetz 《Applied optics》2003,42(7):1306-1307