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991.
With CMOS scaling approaching its limits, there is a great need for advancements in novel devices, disruptive fabrication
technologies, advanced materials and alternative computer architectures for future nanoelectronic systems. The emergence of
memristive devices is one of promising solutions for the post-CMOS era. In this paper, we first introduce the fabrication
of transition metal oxide based memristor cross-bars using nanoimprint lithography (NIL). The fabrication technique is further
improved by using only one NIL step, reducing the fabrication efforts and improving the device performance. With shadow evaporation,
a host of devices such as 2-terminal lateral memristors and 3-terminal memristive devices (memistors) are also demonstrated.
By building memristor cross-bar arrays on foundry-made CMOS substrates using NIL, we have implemented hybrid nano/CMOS architecture.
This hybrid chip provides an FPGA-like functionality with reconfigurable memristors defining data paths to wire logic gates
into digital circuits. Future trends and issues with fabrication of memristive devices are also briefly discussed. 相似文献
992.
建立了ICP-AES测定超导粉中痕量镍的新方法。优化了仪器工作参数,对超导前驱粉中痕量镍测定时的基体干扰及干扰消除方法进行了系统研究,结果表明:大量存在的基体元素产生严重基体效应,导致测定重现性及准确度变差,实验采用分离富集方法以提高测定结果的准确度和精密度。实验中首先用阴离子交换树脂,除去Bi3+及部分Pb2+,Sr2+,Ca2+,Cu2+等基体元素;在碱性条件下再通过甲苯萃取镍与丁二酮肟的络合物、稀盐酸反萃取富集镍;对分离富集条件进行了优化。对模拟标准样品进行测定,分析结果与理论值一致,相对标准偏差为1.9%,方法检出限为0.19μg.g-1。该方法已用于超导前驱粉样品中痕量镍的分析,结果令人满意。 相似文献
993.
Wan WQ Pan QH Jia GJ Xu YZ Lai GQ Liu SX Chen J Yang LM Zhang YF Weng SF Wu JG 《光谱学与光谱分析》2011,31(2):353-356
采用傅里叶变换衰减全反射中红外光谱法检测了24例液氮冻存的脑膜瘤离体样品(其中良性肿瘤12例,有恶性倾向的肿瘤12例),对得到的红外光谱进行整理分析,发现不同类型脑膜瘤组织(如纤维型脑膜瘤和内皮型脑膜瘤)的红外光谱存在着差异,并且同一种类型的脑膜瘤组织,其恶性倾向的程度不同,他们的红外光谱也表现出较为明显的区别,因此,我们可以从各个特征吸收峰的峰位、峰形及峰强等信息的变化来区分脑膜瘤,并可以初步鉴别脑膜瘤的性质;研究结果发现,通过某些特征吸收峰(如1 160cm-1)峰位的变化来鉴别脑膜瘤的性质与病理诊断结果的符合率大于85%,说明傅里叶变换衰减全反射中红外光谱法有可能发展成为一种对样品无损伤、快速的脑肿瘤诊断新方法。 相似文献
994.
A classification of connected vertex‐transitive cubic graphs of square‐free order is provided. It is shown that such graphs are well‐characterized metacirculants (including dihedrants, generalized Petersen graphs, Möbius bands), or Tutte's 8‐cage, or graphs arisen from simple groups PSL(2, p). 相似文献
995.
Based on a general isospectral problem of fractional order and the fractional quadratic-form identity by Yue and Xia, the new integrable coupling of fractional coupled Burgers hierarchy and its fractional bi-Hamiltonian structures are obtained. 相似文献
996.
主要研究改进集的一些拓扑运算性质。首先在改进集条件下给出了拓扑向量空间中两个非空集之和的拓扑内部的一些运算性质。进一步,利用改进集获得了 Flores-Baz′an 和 Hern′andez 提出的假定 B 的一个加强形式。此外,给出了一些例子对主要结果进行了解释。 相似文献
997.
In this paper, we propose a projection subgradient method for solving some classical variational inequality problem over the set of solutions of mixed variational inequalities. Under the conditions that $T$ is a $\Theta $ -pseudomonotone mapping and $A$ is a $\rho $ -strongly pseudomonotone mapping, we prove the convergence of the algorithm constructed by projection subgradient method. Our algorithm can be applied for instance to some mathematical programs with complementarity constraints. 相似文献
998.
Dongzhen Li Xiaodong Xu Yan Cheng Shishu Cheng Dahua Zhou Feng Wu Changtai Xia Jun Xu Jian Zhang 《Journal of Crystal Growth》2010,312(14):2117-2121
A Yb3+-doped CaYAlO4 laser crystal has been grown by the Czochralski technique. The segregation coefficient was measured by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The cell parameters were analyzed with X-ray diffraction experiments. Color defects in Yb:CaYAlO4 have been evidenced to be similar to those in undoped CaYAlO4. The polarized absorption spectra and the fluorescence spectrum of the Yb:CaYAlO4 crystal were measured at room temperature. The fluorescence decay time of the Yb3+ ion was investigated. The results show that Yb:CaYAlO4 has potential as a laser gain medium for an ultrashort laser system. 相似文献
999.
Polypropylene/poly(butyl methacrylate)(PP/PBMA) blends were prepared by diffusion and subsequent polymerization of butyl methacrylate(BMA) in commercial isotactic polypropylene(iPP) pellets.The diffusion kinetics,diametrical distribution of PBMA in a pellet and phase morphology of a typical PP/PBMA blend were investigated. 相似文献
1000.
Interfacial area transport equation (IATE) is considered promising to evaluate dynamic changes of the interfacial area concentration in gas–liquid two-phase flows, which is of significance in characterizing the interfacial structure of the flows. Efforts were made by the authors in the past on the implementation of the IATE into computational fluid dynamics codes, such as Fluent. However, it remained unclear whether the IATE model coefficients derived from one-dimensional IATE model calibrations can be applied to three-dimensional simulations. The current study aimed to examine, primarily by investigating the lateral profiles of phase distributions, the applicability of the coefficients obtained from the one-dimensional IATE model calibration to a three-dimensional simulation of bubbly flow in a pipe. In addition, effects of the lift force on the lateral phase distributions were studied. A new set of the IATE model coefficients was suggested for a three-dimensional bubbly flow simulation. Good agreement was obtained with the updated coefficients between the predicted and measured flow parameters. 相似文献