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1.
采用模压成型方法制备了2种柔软性不同的热塑性聚氨酯/短切碳纤维/碳纳米管(TPU/SCF-CNT)复合材料复制物, 其表面上具有倒金字塔微结构阵列, 内部有SCF与CNT共同构成的导电通路. 将复合材料复制物和相应的复合材料平整片封装成柔性传感器. 结果表明, 压力作用下传感器内复制物和平整片之间的接触电阻因倒金字塔底棱的形变而显著降低. 对使用柔软性较高的复合材料封装的传感器, 虽然其相对迟滞稍大, 但压力作用下倒金字塔底棱形变量较大, 且复制物和平整片内导电通路增加量较大, 因此其在0~2.5 kPa的线性区内具有较高的灵敏度(0.32 kPa?1). 制备的2种传感器均具有快速响应特性, 且能在500 s(约1580次)的循环压缩/释放测试(峰值压力约3 kPa)中保持较稳定的电阻响应. 研究表明, 利用模压成型的表面倒金字塔结构复合材料复制物封装成的柔性压力传感器具有良好的传感性能. 相似文献
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3.
The effects of group-delay difference in an active nonlinear long-period fiber grating (LPFG) made in an erbium-doped amplifying fiber (EDF) are investigated by proposing a general model that include the effects of detuning, group-delay difference, gain saturation, gain bandwidth and Kerr nonlinearity. In particular, we observe a new feature caused by the interaction between the group-delay difference and the gain bandwidth: the pulse breakup effect due to the group-delay difference can be suppressed by the finite bandwidth of the linear gain. 相似文献
4.
The problem of deciding whether a graph manifold is finitely covered by a surface bundle over the circle is discussed in this
paper. A necessary and sufficient condition in term of the solutions of a certain matrix equation is obtained, as well as
a necessary condition which is easy to compute. Our results sharpen and extend the earlier results of J. Leucke-Y. Wu, W.
Neumann, and S. Wang-F. Yu in this topic.
Supported in part by NSFC 相似文献
5.
Suppose V ∪_S W is a strongly irreducible Heegaard splitting of a compact connected orientable 3-manifold M and F_1 and F_2 are pairwise disjoint homeomorphic essential subsurfaces in ?_V. In this paper,we give a sufficient condition such that the self-amalgamation of V ∪_S W along F_1 and F_2 is unstabilized and uncritical. 相似文献
6.
ZHANG Changwen LI Hua DONG Jianmin WANG Yongjuan PAN Fengchun ZHANG Jian GUO Yongquan & LI Wei . School of Physics Microelectronics Shandong University Jinan China . Institute of Functional Materials Central Iron Steel Research Institute Beijing China 《中国科学G辑(英文版)》2005,48(3)
1 Introduction The rare-earth transition-metal intermetallic compounds have been widely investi-gated for many years, among them the Sm-Co series compounds with 1:5 and 2:17 crys-tal structures. These compounds have been used as sintered and bonded permanent magnets since the 1960s[1,2]. Interest recently has been focused on the TbCu7-type struc-ture Sm-Co intermetallic compounds with a strong uniaxial magnetocrytalline anisot-ropy and a low temperature coefficient (β = ?0.11%)[3―6] due t… 相似文献
7.
LEI Fengchun & GUO Xiao Department of Mathematics Harbin Institute of Technology Harbin China 《中国科学A辑(英文版)》2005,48(11):1499-1504
In the present paper, we investigate the non-Heegaard 2-compressible surfaces in small 3-manifolds, and show that such surfaces have some good properties. 相似文献
8.
Within the framework of effective-mass approximation, the binding energy of a hydrogenic donor impurity in a zinc-blende (ZB) InGaN/GaN cylindrical quantum dot (QD) is investigated using a variational procedure. Numerical results show that the donor binding energy is highly dependent on impurity position and QD size. The donor binding energy Eb is largest when the impurity is located at the center of the QD. The donor binding energy is decreased when the dot height (radius) is increased. 相似文献
9.
Xiuxiu Zhang Chenyu Yang Chen Gong Meihuan Liu Wanlin Zhou Hui Su Feifan Yu Fengchun Hu Qinghua Liu Shiqiang Wei 《Angewandte Chemie (International ed. in English)》2023,62(33):e202308082
Synthesis of highly active and durable oxygen evolution reaction (OER) catalysts applied in acidic water electrolysis remains a grand challenge. Here, we construct a type of high-loading iridium single atom catalysts with tunable d-band holes character (h-HL−Ir SACs, ∼17.2 wt % Ir) realized in the early OER operation stages. The in situ X-ray absorption spectroscopy reveals that the quantity of the d-band holes of Ir active sites can be fast increased by 0.56 unit from the open circuit to a low working potential of 1.35 V. More remarkably, in situ synchrotron infrared and Raman spectroscopies demonstrate the quick accumulation of *OOH and *OH intermediates over holes-modulated Ir sites in the early reaction voltages, achieving a rapid OER kinetics. As a result, this well-designed h-HL−Ir SACs exhibits superior performance for acidic OER with overpotentials of 216 mV @10 mA cm−2 and 259 mV @100 mA cm−2, corresponding to a small Tafel slope of 43 mV dec−1. The activity of catalyst shows no evident attenuation after 60 h operation in acidic environment. This work provides some useful hints for the design of superior acidic OER catalysts. 相似文献
10.
Itisinrecentyearsthatthedamagemechanicsissuccessfulinstudyingthefatigueproblems.Thekeytothismethodistodefineanappropriatedamagevariablewhichhasaclearphysicalmeaningandshouldbemeasuredbyasimpleexperimentalprocedure,andthevariablecanbeusedtoestablished… 相似文献