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用CCD摄像机动态估算测量云雾含水量的初步试验 总被引:6,自引:0,他引:6
云雾含水量是一个研究和定义云雾微物理结构的关键物理量 ,它与云雾的强度直接有关。介绍一种以 CCD数字摄像机为核心器件的光学图像传感系统 ,该系统通过基于数字摄像的能见度自动测量技术 ,可以有效反演出云雾的含水量。在报告系统的测量原理、理论方法和系统基本构成后 ,给出了用该系统动态估算测量两次大雾过程的雾含水量与实测雾含水量的对比分析结果。实验结果表明 :用仪器系统动态估算测量的结果与实测值吻合得相当好。两者的均方根差小于 0 .1g/ m3,相对均方根偏差小于 2 0 % 相似文献
174.
本文探讨了使用微透析技术揭示麻醉的神经化学基础的可行性.以水合氯醛为麻醉剂,脑电记录监视脑活动状态,从处于不同麻醉深度的大鼠嗅球中获得微透析样品,经邻苯二甲醛衍生后,利用高效液相色谱-荧光检测对谷氨酸(Glu)和γ-氨基丁酸(GABA)进行了分离分析.结果表明:微透析样品中Glu含量随着麻醉程度的加深逐渐减少,但GABA的含量基本不受麻醉程度的影响,揭示了水合氯醛麻醉过程中对氨基酸类神经递质的影响,并提示微透析是一种可以用于研究麻醉机理和监控麻醉深度的分析技术. 相似文献
175.
重写式光盘染料的存储机理及合成 总被引:2,自引:0,他引:2
综述了可擦重写式光盘染料的有关储存机理及合成方法。参考文献11篇。 相似文献
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G. D. Lafferty 《中国物理 C》2010,34(6):907-911
The BABAR experiment has now completed data taking and with an integrated luminosity of 531 fb^-1 of e^+e^- collision data has recorded some 480 million tau-pair events. Various studies of suppressed, rare and forbidden decays of the tau have been conducted, including searches for high-multiplicity decays, for second-class hadronic weak currents, and for lepton-flavour violation. 相似文献
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Lulu Wang Zexin Xie Cheng Zhong Yongqiang Tang Fengming Ye Liping Wang Yi Lu 《物理化学学报》2020,36(12):1909035-0
Neural electrodes have been extensively utilized for the investigation of neural functions and the understanding of neuronal circuits because of their high spatial and temporal resolution. However, long-term effective electrophysiological recordings in free-behaving animals still constitute a challenging task, which hinders longitudinal studies on complex brain-processing mechanisms at a functional level. Herein, we demonstrate the feasibility and advantages of using a self-spreadable octopus-like electrode (octrode) array for long-term recordings. The octrode array was fabricated by enwrapping a bundle of eight formvar-coated nickel-chromium microwires with a layer of polyethylene glycol in a custom-made mold. After the electrodeposition of platinum nanoparticles, the microwires at the electrode tip were gathered together and then re-enwrapped with a thin layer of gelatin to maintain their structure and mechanical strength for implantation. Shortly after implantation (within 20 min), the biocompatible gelatin encapsulation swelled and dissolved, causing the self-spreading of the recording channels of the octrode array in the brain. The electrochemical characteristics of the electrode/neural tissue interface were investigated by electrochemical impedance spectroscopy (EIS). Four weeks after implantation, the average impedance of the octrodes (1.26 MΩ at 1 kHz) was significantly lower than that of the conventional tetrodes (1.50 MΩ at 1 kHz, p < 0.05, t-test). Additionally, the octrodes exhibited a better pseudo-capacitive characteristic and a considerably faster ion transfer rate at the electrode interface than the tetrodes. Spontaneous action potentials and local field potentials (LFPs) were also recorded in vivo to investigate the electrophysiological performance of the octrodes. The peak-to-peak spike amplitudes recorded for the octrodes were remarkably larger than those recorded for the tetrodes. The signal quality remained at approximately the same level for the four-week period, while the peak-to-peak spike amplitudes recorded for the tetrodes decreased abruptly. Moreover, the voltage amplitudes recorded by the octrodes at 1–200 Hz were notably larger than those by the tetrodes, suggesting a higher sensitivity in the recording of electrophysiological events. Furthermore, we performed immunochemical analyses on the brain tissues at post-implantation to evaluate the histocompatibility of the electrodes. Tissue responses of the octrodes were alleviated considerably, evidenced by the reduced astroglial intensity and increased neuron density around the implant site as compared to the tetrodes, which may be due to the relatively small size of each decentralized recording channel after self-spreading in vivo. Generally, the fabricated octrodes exhibited a lower electrochemical impedance value at the octrode/neural tissue interface and an increased signal quality during the long-term electrophysiological recording in freely moving mice as compared to the conventional tetrodes. All of these are desirable characteristics in neural circuit dissections in vivo. 相似文献
180.
神经电极技术是监测和调控神经活动的重要手段,在基础神经科学研究和神经系统疾病诊疗方面有着广泛的应用。这项技术的关键在于神经电极与生物组织之间形成高效而且稳定的神经界面,从而实现高分辨、安全且长期稳定的神经记录和刺激。碳纳米材料因其优异的电学、力学和化学性质被用于构筑神经界面,形成了多种基于石墨烯和碳纳米管的神经电极及其阵列,包括可以改善界面稳定性从而获得长期稳定电学记录的柔性深度电极、可以实现电生理测量和光学刺激/成像联用的透明电极阵列、以及与磁共振成像高度兼容的神经电极等。本文将综述近年来基于石墨烯和碳纳米管的神经电极技术的发展及应用,并对纳米碳基神经电极的未来发展方向进行展望。 相似文献