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81.
Formation of y hydrides in α titanium involves a hcp → fct lattice transformation with hydrogen as an interstitial diffusing
species. Since the crystallography of this reaction resembles that of a martensitic transformation and the hydrides form at
temperatures where both titanium and hydrogen atoms may have negligible mobility, many investigators have concluded that γ
hydrides form by a martensitic mechanism. In this study, the lengthening kinetics of
γ hydrides were determined using conventional transmission electron microscopy (TEM). The length of the hydrides was measured
as a function of time, temperature, and hydrogen concentration in samples isothermally aged in the range of 25 °C to 80 °C.
These measurements were compared with the Zener-Hillert model of volume-diffusion-controlled precipitate growth. The experimental
results indicate that y hydride growth is diffusionally controlled at 25 °C and possibly interfacially controlled at aging
temperatures of 50 °C and higher. These and other aspects of the transformation are discussed. 相似文献
82.
Wu-Chiang Chan Ping-Chuan Chen Meng-Chin Tsai Ting-Ko Chen 《Engineering Management Journal; EMJ》2017,29(2):87-98
Open innovation has transformed internal novel resource allocation and facilitated diverse interorganizational cooperation models. Previous studies have investigated open innovation archetypes and their formation. However, most researchers have neglected the crucial role that team leaders play in integrating internal and external resources and connecting creative ideas in open innovation. This study investigated the influence of open innovation archetypes and team leaders’ innovation traits on team performance. On the basis of the literature review, the analytical hierarchy process was applied to construct a framework for assessing and selecting team leaders in open innovation. The analysis was completed based on samples from 45 valid respondents (88% return rate) in Taiwan’s high-tech industry. The study results suggested that innovation knowledge is the most crucial innovation criterion for a leader, particularly core knowledge and advanced knowledge. Among the various sub-criteria, extrinsic motivation was the second most important sub-criterion. Leaders with strong innovation motivations are suitable to lead inbound open innovation projects. 相似文献
83.
Volodin V. N. Tuleushev Yu. Zh. Zhakanbaev E. A. Tsai K. V. Rofman O. V. 《Technical Physics Letters》2017,43(1):126-129
Carbon–lead solid solutions coexisting with amorphous carbon have been obtained for the first time in a film coating deposited by ion-plasma sputtering. During subsequent vacuum annealing of carbon–lead films containing more than 68.5 at % Pb, this element almost completely evaporates to leave an amorphous carbon coating on a substrate. During annealing at 1100°C, this amorphous carbon crystallizes into a new hexagonal lattice with unit cell parameters a = 0.7603 nm and c = 0.8168 nm. Characteristic X-ray diffraction data for the identification of this phase are determined.
相似文献84.
S. F. Tsai 《International Journal of Thermophysics》2016,37(3):31
The application of a thermal analysis model to estimate the temperature depression from the ideal fixed-point temperature is important, especially when the chemical analysis of the sample in a cell is insufficient or the cell might have been contaminated during fabrication. This study extends previous work, on thermal analysis with the tin point, to an investigation of the impurity dependence of the silver-point temperature. Close agreement was found between the temperature depression (\(-0.36\) mK) inferred from the thermal analysis of the measured fixed-point plateau and the temperature depression (\(-0.32\) mK) inferred using the sum of individual estimates (SIE) method with an impurity analysis based on glow discharge mass spectrometry. Additionally, the results of the thermal analysis manifest no significant dependence on the rate of solidification, and the scatter of observed gradients was within 0.36 mK among five plateaux with different temperature settings of the furnace. Although the results support the application of both the SIE method and thermal analysis for the silver point, further experiments with cell-to-cell comparisons linked to thermal analysis, a study of the thermometer-furnace systematic effects, the oxygen effect, and the locus of the freezing plateau should be investigated to reach a firm conclusion. 相似文献
85.
Reinforced concrete (RC) walls play an important role in resisting earthquakes, so understanding the lateral load-deformation response of an RC wall subjected to an axial load, shear, and moment is essential to nonlinear structural analysis. In this study, the moment-bending deformation response of an RC wall under an axial load and moment is obtained from moment–curvature analysis using the wall’s proper plastic hinge length. Furthermore, modified compression-field theory, adjusted according to the height–length ratio of the wall, is used to calculate the shear–shear deformation response of the wall under an axial load and shear. By integrating the moment-bending deformation and the shear–shear deformation responses, the lateral load-deformation response of the RC wall under axial load–moment–shear interaction can be reasonably determined. To confirm the reliability of the proposed method, experimental results for 67 RC walls are compared with analysis results from the proposed method. The statistical results show that the proposed method accurately predicts the lateral ultimate load but somewhat underestimates the lateral ultimate deformation. Finally, this paper gives an example using an equivalent column to simulate an RC wall using SAP2000 pushover analysis. 相似文献
86.
87.
Kalashnyk Nataliya Ledieu Julian Gaudry Émilie Cui Can Tsai An-Pang Fournée Vincent 《Nano Research》2018,11(4):2129-2138
Nano Research - The formation of long-range ordered aperiodic molecular films on quasicrystalline substrates is a new challenge that provides an opportunity for further surface functionalization.... 相似文献
88.
Aging and the progression of certain degenerative diseases are accompanied by increases in intracellular fluorescent material, termed "lipofuscin" and ceroid, respectively. These pigments are observed within granules composed, in part, of damaged protein and lipid. Modification of various biomolecules by aldehyde products of lipid peroxidation is believed to contribute to lipofuscin and ceroid formation. However, little direct evidence currently exists because the structures responsible for the fluorescent, cross-linked nature of this material are not well characterized. In this study, we have identified a fluorescent product formed in the reaction of Nalpha-acetyllysine and 4-hydroxy-2-nonenal (HNE), a major product of lipid peroxidation and the most reactive of these compounds under physiological conditions [Esterbauer, H., Shaur, R. J. & Zollner, H. (1991) Free Radical Biol. Med. 11, 81-128]. This fluorescent compound, characterized as a 2-hydroxy-3-imino-1,2-dihydropyrrol derivative, appears to form upon oxidative cyclization of the nonfluorescent 2:1 lysine-HNE Michael adduct-Schiff base cross-link. Polyclonal antibody was raised to the Nalpha-acetyllysine-HNE fluorophore and found to be highly specific to the chromophore structure of the compound. This antibody has been used to conclusively demonstrate that the lysine-HNE derivative of this fluorophore forms on protein upon exposure to HNE. The results of this study therefore provide the basis for future investigations on the contribution(s) of HNE-derived fluorophore formation to lipofuscin and ceroid accumulation. 相似文献
89.
A series of segmented polyurethanes containing 60 wt° of hard segments (HS) was prepared from MDI (4,4-diphenylmethane diisocyanate) ethylene glycol and mixtures of a polyoxyethylene end-capped polyoxypropylene triol and a polyoxyethylene end-capped polyoxypropylene diol. The effects of the content of polyether diol in polyether polyols on phase separation and properties was investigated by dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and investigation of tensile properties. The DSC and DMA results indicate that the polyurethane derived from only polyether triol exhibits obvious phase separation and that the HS is immiscible with the SS, but that the HS is compatible with the HS for the polyurethane derived from polyether diol. As the content of polyether diol increases, the compatibility between HS and SS increases. As the content of polyether diol increases, the tensile strength. elongation. toughness and tear resistance of the polyurethanes increases. but their moduli decrease. The modulus-temperature dependence in the temperature region of –30 to 65 °C increases as the polyether diol content increases. 相似文献
90.
Yu-An Chen Zi-Wei Huang Fang-Sheng Tsai Chang-Yu Chen Cheng-Ming Lin Andrew M. Wo 《Microfluidics and nanofluidics》2011,10(1):59-67
A home-use device that allows rapid and quantitative sperm quality analysis is desirable but not yet fully realized. To aid
this effort, this article presents a microfluidic device capable of quantifying sperm quality in terms of two critical fertility-related
parameters—motile sperm concentration and motility. The microdevice produces flow field for sperms to swim against, and sperms
that overcame the flow within a specified time are propelled along in a separate channel and counted via resistive pulse technique.
Data are compared to two control methods clinically utilized for sperm quality exam—hemocytometer and the sperm quality analyzer.
Results reveal the numbers of pulses generated by passage of sperms correlates strongly with the two control methods: pulse
number from 0 to 335 corresponds to progressively motile sperm concentrations from 0 to 19 × 106/ml (hemocytometer) and Sperm Motility Index from 0 to 204 (sperm quality analyzer). The microdevice should be applicable
to facilitate self-assessment of sperm quality at home. 相似文献