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排序方式: 共有1054条查询结果,搜索用时 22 毫秒
1.
The three-dimensional morphology of polyethylene single crystals grown from dilute solution has been examined by atomic force microscopy. Single crystals were deposited on a soft ground of aqueous solution of poly(vinyl alcohol) (PVA) to avoid the collapse of thin lamellar crystals with thickness of 10 nm. The observation of single crystals on dried PVA clarifies the morphology of a chair type crystal as well as well-known hollow pyramidal type. It has been confirmed that the screw dislocations in the chair type follow a selection rule of the handedness in a manner to relieve the distortion in the chair type. 相似文献
2.
Water-soluble chitin was successfully crosslinked to varying extents with glutaraldehyde in homogeneous aqueous solutions to improve the properties as an adsorbent for metal cations, and the effects of crosslinking were discussed. Complete insolubilization was achieved with the fivefold excess aldehyde, but, in terms of adsorptivity of Cu2+, the chitin crosslinked at an aldehyde/amino group ratio of 1.0 was found to exhibit remarkable capacity and was much superior to others. The desorption of Cu2+ from the adsorption complex was also attained effectively at pH 2.0. These results indicated that the loose crosslinking was quite simple and efficient to produce high capacity adsorbents for practical use. Thermal behavior of the crosslinked chitin was examined by TMA and TGA; a softening phenomenon was observed at 145°C. 相似文献
3.
Tatsuo Inoue Nobutada Ohno Akihiko Suzuki Toshihide Igari 《Nuclear Engineering and Design》1989,114(3)
Uniaxial tests to identify plasticity-creep interaction in
steel at 600°C were carried out as the Benchmark Project by the Subcommittee on Inelastic Analysis and Life Prediction, JSMS. The purpose of this paper is to present recent experimental data and predictions of constitutive models obtained in the project. Ten types of constitutive models were utilized to compare analytical predictions to sixteen benchmark experiments which are grouped into four categories: (I) tensile and creep tests under monotonic loading, (II) mixed mode tests under plastic and creep loading, (III) ratcheting deformation tests under program loads, and (IV) cyclic deformation tests under the combination of different strain rates. The benchmark tests in Group IV are used to estimate the creep-fatigue life of
steel; the results will be published in a separate paper. 相似文献
4.
Keita Ikeue Shingo Ando Tomohiro Mitsuyama Yusuke Ohta Keishi Arayama Akiko Tsutsumi Masato Machida 《Topics in Catalysis》2008,47(3-4):175-180
Lanthanide-based oxysulfides and sulfide, LnTaO3.5S0.5, Ln10OS14 (Ln = La, Pr, Nd, Sm) and La4In5S13, were successively synthesized by sulfurization in a flowing H2S. The sulfurization decreased the band-gap energies from >4 eV to <3eV, because of the formation of occupied S3p orbitals
on the top of valence band. In accordance with the small band gap, the H2 evolution from a 0.01 M Na2S and 0.01 M Na2SO3 solution system was observed under irradiation of light up to >500 nm. The rate of H2 evolution under light irradiation of >500 nm increased in the order of Ni/LaTaO3.5S0.5 < Ru/La10OS14 < Pt/La4In5S13. 相似文献
5.
This study was performed in order to clarify crack opening displacement (COD) of through-wall cracks in a plate subjected to bending load. The former COD evaluation methods were mainly developed corresponding to tensile load, but there has been nothing that has been developed corresponding to bending load. Therefore, the authors evaluated CODs of the through-wall cracks in plates which were subjected to a bending load using finite element method (FEM) analyses, and proposed a simplified COD evaluation method accounting for both tensile and bending loads. The proposed method is useful for leakage evaluation at a crack opening of an elbow crown or in the vicinity of the coolant surface of a vessel in which the bending stress is relatively large. 相似文献
6.
New technologies such as power electronics have made it possible to change continuously the impedance of a power system not only to control power flow but also to enhance stability. A power system incorporating a variable impedance apparatus such as a variable series capacitor (VSrC) and high-speed phase shifter (HSPS) is called VIPS (Variable Impedance Power System) by the authors. This paper proposes a novel control method of VIPS apparatus such as VSrC and HSPS installed at an interconnecting point for stabilizing inter-area unstable and/or oscillatory modes. The proposed design method of the control system is a kind of hierarchical decentralized control method of a large-scale power system based on a Lyapunov function. Under the proposed control scheme, each subsystem can be stabilized independently by local controllers such as AVR, speed governor and PSS, and then the whole interconnected system can be stabilized by VIPS apparatus taking into account interactions between subsystems. The effectiveness and robustness of the VIPS apparatus control are shown by numerical examples with model systems including a large-scale power system. 相似文献
7.
Akihiko Sakurai Mina Masuda Mikio Sakakibara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2003,78(9):952-958
The removal of phenol by peroxidase‐catalysed polymerization was examined using Coprinus cinereus peroxidase in the presence of surfactants. The non‐ionic surfactants with poly(oxyethene) residues, Triton X‐100, Triton X‐405 and Tween 20, enhanced the phenol removal efficiency at a level similar to high relative molecular mass poly(ethylene glycol) (relative molecular mass 3000). Although the improvement in the removal efficiency was less than that of Triton X‐100, Span 20, sodium lauryl sulfate (SDS) and lauryl trimethylammonium bromide (DTAB) also enhanced the removal efficiency. The requirement of the enzyme for almost 100% removal of 100 mg dm?3 phenol decreased to one‐fourth by the addition of 30 mg dm?3 Triton X‐100. Triton X‐100, Triton X‐405, Tween 20 and DTAB could reactivate the enzyme precipitated with the phenol polymer, leading to the restarting of the phenol removal reaction. Copyright © 2003 Society of Chemical Industry 相似文献
8.
Tohru Morii Hiroyuki Hamada Muriel Desaeger Akihiko Gotoh Atsushi Yokoyama Ignaas Verpoest Zen-ichiro Maekawa 《Composite Structures》1995,32(1-4):133-139
This study deals with the impact property and damage tolerance of matrix hybrid composite laminates with different laminate constitution. The matrix hybrid composite laminates consisted of the laminae with a conventional epoxy resin and the laminae with a flexible epoxy resin modified from the conventional resin to avoid the interlaminar delamination. The impact energy absorption ratio greatly depended on the matrix resin placed at the impact face. The energy absorption was almost constant if the conventional resin was placed at the impact surface layer, while it increased exponentially with the increasing fraction of the flexible resin if the flexible resin was placed at the impact face. The impact energy was absorbed by the damage development and propagation in the laminate with conventional resin laminae as the impacted face, while it was absorbed by both the recoverable deformation of the flexible resin and the damage propagation in the laminate with flexible resin laminae as the impacted face. 相似文献
9.
Highly transparent cellulose hydrogels with physical crosslinkage were prepared from nonaqueous organic cellulose solutions and viscose by coagulating and regenerating cellulose in an aqueous solution containing a water‐miscible organic solvent. Nonaqueous organic cellulose solutions used were LiCl/dimethylacetamide, paraformaldehyde/dimethyl sulfoxide, and triethylammonium chloride/dimethyl sulfoxide. Preparation conditions and physical properties of the transparent cellulose hydrogels were studied. The transparency of the cellulose hydrogels depended on the composition of the aqueous solution containing the organic solvent. Furthermore, transparent cellulose hydrogels from viscose showed high tensile strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3020–3025, 2003 相似文献
10.
Keiji Itabashi Takuji Ikeda Akihiko Matsumoto Kunikazu Kamioka Masanao Kato Kazuo Tsutsumi 《Microporous and mesoporous materials》2008,114(1-3):495-506
Four types of Rb-aluminosilicate zeolites were hydrothermally synthesized in pure phase for the first time from Rb-aluminosilicate gels without using any organic structure-directing agent (SDA) under stirring conditions. The crystal structure of each zeolite was refined by Rietveld analysis of the X-ray diffraction (XRD) data. These crystal structures were confirmed to be Rb-mordenite, Rb-merlinoite, a new aluminosilicate zeolite with an ATT framework topology, and Rb-offretite denoted by RMA-1, RMA-2, RMA-3, and RMA-4, respectively. The Si/Al ratio of RMA-1 with an MOR topology varied from 5.3 to 8.0; however, the variation of the Si/Al ratios of the other zeolites was rather small. The crystal system of RMA-2 was tetragonal with space group I4/mmm, where two Rb sites were distributed at the center of an 8-membered ring (MR). On the other hand, two Rb sites in RMA-3 were located at the center of the 8-MR in small two cages. The structure of RMA-4 was identified as the OFF type with a local disorder or defect, which included a small amount of an intergrown ERI phase. 相似文献