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排序方式: 共有719条查询结果,搜索用时 15 毫秒
31.
Yun‐Hsuan Huang Shu‐Hsien Huang Wei‐Chi Chao Chi‐Lan Li Yun‐Ying Hsieh Wei‐Song Hung Der‐Jang Liaw Chien‐Chieh Hu Kueir‐Rarn Lee Juin‐Yih Lai 《Polymer International》2014,63(8):1478-1486
To improve the pervaporation performance in separating an aqueous ethanol solution, polyamide thin‐film composite (TFC) membranes (m‐tolidine‐H‐TMC/mPAN) were prepared through the interfacial polymerization reaction between trimesoyl chloride (TMC) and 2,2'‐dimethylbenzidine hydrochloride (m‐tolidine‐H) on the surface of a modified polyacrylonitrile (mPAN) membrane. The effects of the feed ethanol concentration on the pervaporation performance and the durability of m‐tolidine‐H‐TMC/mPAN TFC membranes were investigated. To choose the optimal mPAN membrane as the TFC substrate, the effect of hydrolysis time on the chemical properties and separation performance of an mPAN substrate was also studied. An appropriate hydrolysis time of 15 min was chosen to obtain the mPAN substrate due to the corresponding high permeation flux. The m‐tolidine‐H‐TMC/mPAN TFC membrane exhibited a high pervaporation performance for ethanol dehydration. A positron annihilation lifetime spectroscopy experiment was used to estimate the mean free‐volume radius of the m‐tolidine‐H‐TMC polyamide selective layer, which lay between the radii of the water and ethanol molecules. © 2013 Society of Chemical Industry 相似文献
32.
Yu-Hao Lee Tsun-Cheng Wu Chao-Wu Liaw Ten-Chin Wen Shih-Wei Feng Jey-Jau Lee Yao-Ting Wu Tzung-Fang Guo 《Organic Electronics》2013,14(4):1064-1072
This work studies a series of fluorescent materials, benzo[k]fluoranthene-based linear acenes, and uses these materials directly as the non-doped active layer to fabricate deep blue- to green-emissive organic light emitting diodes (OLEDs). Experimental results indicate that benzo[k]fluoranthene-based linear acenes with different substituents in pristine films have a wide range and strong intensity of the luminescence spectra. The substituents of benzo[k]fluoranthene derivatives modulate the lifetime of the excited state and PL spectra of excitonic, excimer or both emissions in the solid state. Controls of emission spectra are exploited in fabricating high-performance non-doped deep blue to green OLEDs with electroluminescence in the deep blue region (420–460 nm), green region (480–580 nm) or both (430–580 nm). 相似文献
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Yoshihiko Yokoyama D. Gary Harlow Peter K. Liaw Akihisa Inoue 《Metallurgical and Materials Transactions A》2010,41(7):1780-1786
High fatigue strength is one of the important factors that facilitates the industrial usage of bulk metallic glasses (BMGs).
Fatigue data were analyzed using the Weibull probability models for BMGs produced with different casting processes in order
to study the reliability of fatigue strengths of cast glassy alloys. The fatigue data of tilt-cast and high-pressure-cast
BMGs can be explained by a three-parameter Weibull cumulative distribution function (cdf) and a mixture model of two-parameter
Weibull cdfs, respectively. We conclude that the cast defects, which reduce fatigue strength, should be eliminated in order
to realize a high reliability of fatigue strengths. 相似文献
35.
D. Y. Cong Y. D. Wang X. Zhao L. Zuo R. Lin Peng P. Zetterström P. K. Liaw 《Metallurgical and Materials Transactions A》2006,37(5):1397-1403
Three ferromagnetic shape-memory alloys with the chemical compositions of Ni53Mn25Ga22, Ni48Mn30Ga22, and Ni48Mn25Ga22Co5 were prepared by the induction-melting and hot-forging process. The crystal structures were investigated by the neutron powder
diffraction technique, showing that Ni53Mn25Ga22 and Ni48Mn25Ga22Co5 have a tetragonal, 14/mmm martensitic structure at room temperature, while Ni48Mn30Ga22 has a cubic, L21 austenitic structure at room temperature. The development of textures in the hot-forged samples shows the in-plane plastic
flow anisotropy from the measured pole figures by means of the neutron diffraction technique. Significant texture changes
were observed for the Ni48Mn25Ga22Co5 alloy after room temperature deformation, which is due to the deformation-induced rearrangements of martensitic variants.
An excellent shape-memory effect (SME) with a recovery ratio of 74 pct was reported in this Ni48Mn25Ga22Co5 polycrystalline alloy after annealing above the martensitic transformation temperature, and the “shape-memory” influence
also occurs in the distributions of grain orientations. 相似文献
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37.
C. H. Liu L. W. Wu S. J. Chang J. F. Chen U. H. Liaw S. C. Chen 《Journal of Materials Science: Materials in Electronics》2004,15(2):91-93
Electrical properties of Si-implanted and co-implanted with Mg or Be in semi-insulating GaAs was studied. The Si-implanted MESFETs with and without buried p-layer (formed by Mg or Be) have been fabricated and characterized by their d.c. and r.f. performance. The experimental results showed that the device with a buried p-layer can effectively suppress the substrate leakage current (thus good pinch-off characteristic) and obtained higher gain linearity than these without a buried p-layer. For 1 m×100 m MESFETs device with co-implantation of Si (8×1012 cm–2) and Be (6×1011 cm–2) demonstrated uniform transconductance (gm) of 115 mS mm–1 with the gate voltage ranging from –1 to 1 V and reduced pinch-off voltage compared to those with co-implantation of Si and Mg (6×1011 cm–2). The measured fT and fmax of a 1 m×25 m MESFET with co-implantation of Si and Be are 10 and 39 GHz, respectively. However, FETs with increased Mg dose (from 6×1011 cm–2 to 2×1012 cm–2) in a buried p-layer can obtain higher transconductance and saturation current. 相似文献
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Pfiester J.R. Baker F.K. Sivan R.D. Crain N. Lin J.-H. Liaw M. Seelbach C. Gunderson C. Denning D. 《Electron Device Letters, IEEE》1990,11(6):253-255
An inverse-T lightly doped drain (ITLDD) CMOS process which features improved hot-carrier effects and self-aligned source/drain and channel implantation profiles is presented. Compensation effects by the heavy channel doping on the light N-/P- profile are minimized in this ITLDD structure, because the implants are self-aligned to the polysilicon-gate edge. In addition, because selective polysilicon deposition rather than an incomplete poly-gate etchback is used to define the ITLDD structure, a simpler, more manufacturable process is obtained due to improved control of the thin poly-gate shelf thickness 相似文献