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931.
Li S. Zhang H. Lu P. Zhu W. Edelman H. Rea C. Tabat N. Mao S. Brown D. Montemorra M. Palmer D. 《IEEE transactions on magnetics》2006,42(12):3874-3879
In perpendicular recording, substantial erasure of the stored data patterns can occur during the writing process. Among all those erasure processes, side-track erasure (STE) is one of the critical issues in drive head/media integration. Unlike the adjacent track erasure (ATE) process, the locations of the STE affected areas are often many tens of tracks away from the central writing track location. In this work, we report on an experimental investigation and quantification of the general attributes and the origins of the STE processes in various situations. Particularly, we thoroughly characterize some distinctive signatures and behaviors of STE processes by employing both the amplitude- and bit-error-rate-based STE measurement methods in combination with a novel magnetic force microscope characterization technique 相似文献
932.
933.
四川盆地中部上三叠统香溪群岩性油气藏圈闭类型及其特征 总被引:4,自引:0,他引:4
四川盆地川中地区构造平缓,大型断裂欠发育,已发现的油气藏与背斜关系并不十分密切。研究认为,川中地区香溪群主要发育岩性圈闭,根据圈闭形成主控因素,结合香溪群沉积前的古地貌特征和裂缝发育特点,将川中香溪群岩性圈闭划分为4种类型:①与地层尖灭相关的地层—岩性圈闭;②与沉积—成岩相变密切相关的成岩—岩性圈闭;③与古地貌有关的差异压实作用形成的岩性圈闭;④与断层转化调节相关的裂缝—岩性复合圈闭。其中成岩—岩性圈闭和地层—岩性圈闭,是川中香溪群最重要的、分布最广泛的圈闭类型。 相似文献
934.
Ping Liu Zheng-Fan Li Guo-Bing Han 《Electromagnetic Compatibility, IEEE Transactions on》2006,48(3):485-492
In this paper, the asymptotic waveform evaluation (AWE) technique is first applied to the conventional eigenmode expansion method for characterizing a power/ground (P/G) plane pair and analyzing the simultaneous switching noise on such plane pairs for printed circuit boards or multichip modules. The application of AWE avoids a large number of iterations in computing the impedance frequency response of a P/G plane pair structure and greatly reduces the computation time. Meanwhile, to obtain an accurate solution in an entire frequency range, we employ the complex frequency hopping technique which can help select multiple expansion points. In addition, the proposed approach can also be used to characterize the P/G plane pair structures with irregular shapes. Three examples demonstrate its high efficiency and good accuracy. 相似文献
935.
A series of polyurethane microcapsules containing a phase change material (PCM) of n‐octadecane was successfully synthesized by an interfacial polymerization in aqueous styrene‐maleic anhydride (SMA) dispersion with diethylene triamine (DETA) as a chain extender reacting with toluene‐2,4‐diisocyanate (TDI). The average diameter of microPCMs is in the range of 5–10 μm under the stirring speed of 3000–4000 rpm. Optical and SEM morphologies of microPCMs had ensured that the shell was regularly fabricated with the influence of SMA. FTIR results confirmed that the shell material was polyurethane and the SMA chains associated on core material reacted with TDI forming a part of shell material. The shell thickness was decreasing in the range of 0.31–0.55 μm with the molar ratio of DETA/TDI from 0.84 to 1.35 and the weight of core material increasing from 40 to 80% (wt %). By controlling the weight ratio of PCM as 40, 50, 60, 70, and 80% in microPCMs, it was found using DSC that the Tm and Tc of microPCMs were in the range of 29.8–31.0oC and 21.1–22.0°C and an obvious phase change had been achieved nearly the same temperature range of that of PCM. The results from release curves of microPCM samples prepared by 1.4, 1.7, and 2.0 g of SMA indicated the release properties were affected by the amount of the dispersant, which attributed to the emulsion effect and shell polymerization structure. The above results suggest that the shell structure of microPCMs can be controlled and the properties of microPCMs determined by shell will perform proper practical usage. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4996–5006, 2006 相似文献
936.
Guo Dong Zhu Jing Xu Xue Jian Yan Jie Li Zhi Gang Zeng Miao Shen Li Zhang 《Thin solid films》2006,510(1-2):181-183
This paper introduces the Force Modulation technique to the study of crystallization process in ferroelectric vinylidene fluoride and trifluoroethylene copolymer films. Using this technique we have successfully visualized ferroelectric crystalline domains and observed that these ferroelectric domains grow out from amorphous phase, unite into strip-like structures, and finally congregate into a union. Force Modulation can weaken the influence of topography on imaging of ferroelectric domains, and reveal more details, which are difficult to be observed in topographical image. 相似文献
937.
Jau-Jiun Chen Soohwan Jang F. Ren Yuanjie Li Hyun-Sik Kim D. P. Norton S. J. Pearton A. Osinsky S. N. G. Chu J. F. Weaver 《Journal of Electronic Materials》2006,35(4):516-519
Wet etch rates at 25°C for Zn0.9Mg0.1O grown on sapphire substrates by pulsed laser deposition (PLD) were in the range 300–1100 nm · min−1 with HCl/H2O (5×10−3−2×10−2 M) and 120–300 nm · min−1 with H3PO4/H2O (5×10−3−2×10−2 M). Both of these dilute mixtures exhibited diffusion-limited etching, with thermal activation energies of 2–3 kCal · mol−1. By sharp contrast, the etch rates for ZnO also grown on sapphire by PLD were much slower in similar solutions, with rates
of 1.2–50 nm · min−1 in HCl/H2O (0.01–1.2 M) and 12–54 nm · min−1 in H3PO4/H2O (0.02–0.15 M). The etching was reaction limited over the temperature range 25–75°C, with activation energies close to 6
kCal · mol−1. The resulting selectivity of Zn0.9Mg0.1O over ZnO can be a high as ∼400 with HCl and ∼30 with H3PO4. 相似文献
938.
循环荷载作用下饱和黏性土的弹塑性双面模型 总被引:2,自引:0,他引:2
基于作者新近提出的一种混合塑性硬化准则和临界状态土力学理论建立了一个三维形式表述的适于饱和黏性土的弹塑性双面模型,此硬化准则是著名的M asing方法在三维应力空间中的推广。该模型的二维形式已采用饱和黏性土样室内动态三轴不排水剪切试验的结果进行了验证并已在另文发表。本文所建的三维弹塑性动本构模型与一个半经验的孔隙水压力增长模式相结合,通过有限元程序ABAQUS*对一个循环荷载作用下的条形基础下部地基土层内的位移、应力分布和超孔隙水压力随时间的变化进行了分析,计算结果表明模型预测的地基土的力学响应是符合实际的。 相似文献
939.
Development of a low cost microwave mixer using a broad-band substrate integrated waveguide (SIW) coupler 总被引:2,自引:0,他引:2
Ji-Xin Chen Wei Hong Zhang-Cheng Hao Hao Li Ke Wu 《Microwave and Wireless Components Letters, IEEE》2006,16(2):84-86
A low cost single-balanced mixer is designed using a newly designed 90/spl deg/ substrate integrated waveguide (SIW) 3-dB coupler, which takes the advantages of low cost, low profile, and high performance. An X-band single-balanced SIW mixer is designed and fabricated with a standard printed circuit board process. Measured conversion loss of 6.8dB and the wide-band response from 8.5 to 12GHz are presented. 相似文献
940.
This article presents a two-dimensional transient model for gas-solids flow and heat transfer through pipes using the coupled Computational Fluid Dynamics and Discrete Element Method approach. Numerical simulations have been conducted to examine the modification of fluid thermal structure due to the presence of particles in a pneumatic transport pipeline. Modeled results have demonstrated the key role of transversal motion of rebounding particles in the pipe cross section in altering fluid temperature. Further implementation of this modeling technique in air-drying processes is discussed and possible experimental methods for the measurement of in situ particle and fluid motion and temperature profile are cited. 相似文献