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121.
应用ICP-AES法测定钨酸钇钾[kY(WO4)2]激光晶体中的Er和Nd。试样用磷酸分解,Tm被选作内标元素。Er和Nd的回收率分别为98.6%-105.3%和96.5%-105.8%,相对标准偏差分别为1.90%和1.60%。  相似文献   
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Polymer thin-film transistors (PTFTs) based on poly(2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) semiconductor are fabricated by spin-coating process and characterized. In the experiments, solution preparation, deposition and device measurements are all performed in air for large-area applications. Hysteresis effect and gate-bias stress effect are observed for the devices at room temperature. The saturation current decreases and the threshold voltage shifts toward the negative direction upon gate-bias stress, but carrier mobility hardly changes. By using quasi-static C-V analysis for MOS capacitor structure, it can be deduced that the origin of threshold-voltage shift upon negative gate-bias stress is predominantly associated with hole trapping within the SiO2 gate dielectric near the SiO2/MEH-PPV interface due to hot-carrier emission.  相似文献   
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A novel technique is proposed for the management of a 2D reconfigurable device in order to get true hardware multitasking. We use a Vertex List Set to keep track of the free area boundary. This structure contains the best candidate locations for the task, and several heuristics are proposed to select one of them, based in fragmentation and adjacency. A Look-Ahead heuristic that anticipates the next known event is also proposed. A metric is used to estimate the fragmentation status of the FPGA, based on the number of holes and their shape. Defragmentation measures are taken when needed.  相似文献   
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This work presents a detailed case study in customizing a configurable, extensible, 32-bit RISC processor with vector/SIMD instruction extensions for the efficient execution of block-based video-coding algorithms utilizing a proprietary co-design environment. In addition to the default Full-Search motion estimation of the MPEG-2 Test Model 5, fourteen fast ME algorithms were implemented in both scalar and vector form. Results demonstrate a reduction of up to 68% in the dynamic instruction count of the full search-based encoder whereas the fast motion estimation algorithms achieved a reduction in instruction count of nearly 90%, both accelerated via three 128-bit vector/SIMD instructions when compared to the scalar, reference implementation of the standard. We address in detail the profiling, vectorization and the development of these vector instruction set extensions, discuss in depth the implementation of a parametric vector accelerator that implements these instructions and show the introduction of that accelerator into a 32-bit RISC processor pipeline, in a closely-coupled configuration.  相似文献   
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