富含纤维素类农作物秆与丙烯酸接枝共聚制备高倍率吸水树脂

用棉花秆、麦秆和玉米秆等富含纤维素类农作物秆与丙烯酸接枝共聚制备了高倍率的吸水树脂. 研究了不同水质(去离子水、自来水及雨水)对接枝产物吸水性能的影响. 采用棉花秆、麦秆、玉米秆与丙烯酸的接枝产物对去离子水的吸水倍率分别为930, 790和630 g/g, 对自来水的吸水倍率分别为670, 350和250 g/g, 用玉米秆/地瓜淀粉混合物制备的接枝产物对雨水的吸水倍率为540 g/g. 为棉花秆、 麦秆及玉米秆等富含纤维素的农作物秆的深加工与应用开辟了一条途径.     

合成孔径雷达复合干扰机研究

分析了SAR的回波信号处理原理。在现有有源欺骗干扰信号实现方式的基础上,提出了一种复合式干扰机。该干扰机可以根据不同的干扰效果,选择工作方式,实现应答、转发及散射波干扰。     

Self-compliance multilevel storage characteristic in HfO_2-based device

In this paper, the self-compliance bipolar resistive switching characteristic of an HfO_2-based memory device with Ag/HfO_2/Au structure for multilevel storage is investigated. By applying a positive voltage, the dual-step set processes corresponding to three stable resistance states are observed in the device. The multilevel switching characteristics can still be observed after 48 hours. In addition, the resistance values of all the three states show negligible degradation over 104 s,which may be useful for the applications in nonvolatile multilevel storage.     

星载SAR无源干扰分析

介绍了对星载合成孔径雷达（SAR）进行无源干扰的特点与应用,分析了箔条和等离子体干扰方式对星载SAR的干扰特性,并对其干扰情况进行了仿真。结果表明,当单一的无源干扰方式不能起到理想的干扰效果时,应当采用多种干扰方式相结合的手段对SAR进行干扰。     

TiO_x-based self-rectifying memory device for crossbar WORM memory array applications

Resistive switching with a self-rectifying feature is one of the most effective solutions to overcome the crosstalk issue in a crossbar array. In this paper, a memory device based on Pt/TiO_x/W structure with self-rectifying property is demonstrated for write-once-read-many-times(WORM) memory application. After programming, the devices exhibit excellent uniformity and keep in the low resistance state(LRS) permanently with a rectification ratio as high as 10⁴ at ±1 V. The self-rectifying resistive switching behavior can be attributed to the Ohmic contact at TiO_x/W interface and the Schottky contact at Pt/TiO_x interface. The results in this paper demonstrate the potential application of TiO_x-based WORM memory device in crossbar arrays.     

SAR散射波干扰实现方法的研究

根据SAR信号的传播过程和散射波干扰原理，提出了一种散射波干扰的实现方法——干扰机转发地物散射波干扰，即干扰机接收到经地物散射的SAR信号，向SAR接收系统转发，形成散射波干扰。通过分析干扰信号的数学模型，证明了干扰机转发地物散射波干扰信号与干扰机转发SAR信号散射波干扰信号具有相同的数学模型，且能够在距离向和方位向实现二维相干干扰，使SAR图像模糊。最后通过计算机仿真验证了干扰机转发地物散射波干扰的干扰效果。     

二元光学

二元光学是衍射型光学元件新的制作技术。衍射型光学元件是根据光衍射现像的原理,即从波动光学的观点出发,所设计的光学元件。与此相反,现在使用最多的透镜和棱镜等光学元件是按折射定律把光作为光线来处理,即从所谓的几何光学的观点出发所设计的折射型光学元件。目前,几何光学之所以在多种光学领域中仍处最重要的地位,