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31.
K. Nakano S. Tomiya M. Ukita H. Yoshida S. Itoh E. Morita M. Ikeda A. Ishibashi 《Journal of Electronic Materials》1996,25(2):213-216
Using electroluminescence (EL) topography and transmission electron microscopy (TEM), we investigated the nonluminescent regions
which form while current is being injected into ZnMgSSe/ZnSSe/ZnCdSe-based blue light emitters. Small dark spots were observed
just after turn-on and spread out forming rough nonluminescent triangles in the <100> directions in the EL image of the active
region. TEM studies showed that the small dark spots are pre-existing stacking faults originating at the substrate/epitaxial
layer interface. The nonluminescent triangles were found to be a dense region of dislocation dipoles and dislocation loops.
Each dipole was aligned along two <110> directions in the {111} planes. The Burgers vectors were of the type a/2<011> inclined
at 45° to the (001) junction plane. 相似文献
32.
José Vicente Calvano Antônio Carneiro de Mesquita Filho Vladimir Castro Alves Marcelo Soares Lubaszewski 《Microelectronics Journal》2002,33(10):823-834
This work presents a method for synthesizing testable continuous-time linear time-invariant electrical networks using 1st order blocks for the implementation of analog linear circuits. A functional-structural fault model for the block, and a fault dictionary are proposed together with a simple set of test vectors. The method allows, also, the fault grade evaluation for the modeled faults. The results obtained from the two application examples have shown the suitability of the approach as a design for test method for analog circuits. 相似文献
33.
Syntheses of Two Potential Ligands for Tc-99m Labeling as Diagnosis Agents of Alzheimer''''s Disease
Two types of ligands-biphenyl and stilbene derivatives, whichcan be labeled with Tc-99m for the diagnosis of Alzheimer'sdisease (AD) have been synthesized successfully. The key stepsin these two syntheses involved Suzuki reaction and Wittig reac-tion respectively. The new discovered debromination reactionmay be expanded to the compounds with double or triple bondadjacent to the carbon atom bearing the bromine atoms. Thesetypes of syntheses provide a route to a series of biphenyl andstilbene derivatives that will benefit the search of new imagingagents for AD. 相似文献
34.
In this review, we check out the number of published literature in the field of ECL biosensors trends during nearly a decade, and compare the research status of four different types of biosensors; summarize the application forms of nanomaterials in ECL biosensor. We have an overview of the building patterns and application example of the four main types of biosensors in the paper. 相似文献
35.
M.?SunEmail author Y.?Wu J.?Li N.?H.?Wang J.?Wu K.?F.?Shang J.?L.?Zhang 《Plasma Chemistry and Plasma Processing》2005,25(1):31-40
OH radical in the corona discharge with pipe–nozzle–plate electrode has been diagnosed by optical emission spectroscopy. Spatial variations of OH radical emission in discharge gap have been measured. Relative intensity of OH radical emission spectroscopy increases with increasing water vapor flux injected into the reactor or intensity of electric field supported. In positive pulsed corona discharge, relative intensity is higher than that in positive DC corona discharge and lower than that in negative DC corona discharge. Strongest intensity of OH radical spectrum appears within the range of 5 mm near the discharge nozzle- electrode. In addition, it is proved that the efficiency of desulphurization from flue gas by pulsed corona discharge plasma processes can be improved when OH radical is produced in the reactor. 相似文献
36.
微量元素锌在治疗Bell麻痹中的作用 总被引:1,自引:0,他引:1
陈贤雄 《广东微量元素科学》2002,9(3):31-35
为探讨急性早期应用补锌和综合疗法治疗Bell麻痹 ,将 1 5 8例Bell麻痹患者 ,随机分成两组 :(1 )补锌组 (补锌 +综合疗法 ) ;(2 )对照组 (单纯综合疗法 )。对其进行了观察对比治疗 ,同时检测了所有患者治疗前后自身对照发锌值 ,还对所有患者进行了定位诊断、面神经电反应测试、并对面肌功能进行评分。结果表明 ,对定位诊断其病变在D段、面肌功能评分在 1 1分以下、面神经无电反应患者 ,即使给予早期综合治疗 ,效果仍较差 ,而早期给予补锌加综合治疗效果优于对照组 ,其它段内患者治疗次数和治愈天数也均优于对照组。可见微量元素锌在发挥免疫应答、免疫调控中的重要作用 相似文献
37.
Boundary scan test,test methodology,and fault modeling 总被引:1,自引:0,他引:1
The test technique called boundary scan test (BST) offers new opportunities in testing but confronts users with new problems too. The implementation of BST in a chip has become an IEEE standard and users on board level are the next group to begin thinking about using the new possibilities. This article addresses some of the questions about changes in board-level testing and fault diagnosis. The fault model itself is also affected by using BST. Trivial items are extended with more sophisticated details in order to complete the fault model. Finally, BST appears to be a test technique that offers a high degree of detectability on board level, but for diagnosis, some additional effort has to be made. 相似文献
38.
This paper describes why the k-dimension maximal oriented energy subspace of the measurable voltage-change matrix id the optimal feature to locate faults in a population of circuits. The paper elaborately designs a "nearness" concept, which is used to construct a fault candidate set in a small size, and proposes a maximal nearness criterion. On the basis of these, the paper presents a novel algorithm to efficiently improve the accuracy and speed of fault locating. 相似文献
39.
针对复杂机载环境应力条件下航空电子产品故障预测所面临的退化趋势差异大、训练数据样本量小等问题,提出了一种改进长短期记忆(Long Short-Term Memory, LSTM)神经网络模型与集成学习框架相结合的故障预测方法,以满足现代综合航空电子系统智能调度管理与自主维护保障的需求。该方法在LSTM模型中引入Dropout机制,构建基于不同历史数据集的差异性LSTM模型组,以解决故障预测时序信息记忆问题与小样本条件下数据驱动模型训练过拟合问题;采用Adaboosting算法计算模型权重,并基于实时数据动态调整,以滤除复杂机载环境应力引入的预测误差,解决多模型融合的性能差异问题。最后,采用NASA公开的锂电池退化数据集进行仿真验证,实验结果表明,相较于传统BP神经网络、经典LSTM和LSTM基模型,该方法具有更高的趋势拟合度和预测精度。 相似文献
40.