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971.
972.
在多年实践经验基础上,用氧含量X1(质量分数)0.20%~0.38%的四种钽粉,控制钽阳极中残余氧含量X2(质量分数)在0.08%~0.20%间,采用正交设计实验研究了对其漏电流的影响,并建立了漏电流峰值IL和X1、X2间的预示方程,描述了漏电流和钽粉氧含量(X1)、残余氧含量(X2)间的关系。随后,用预示方程讨论了钽中氧和钽阳极中残余氧对其漏电流的影响。 相似文献
973.
974.
介绍一种研究红外吸收光谱的双光束光解方法。用紫外激光300nm解离在C6H12中的Cr(CO)6和用可见激光532nm解离Cr(CO)5.C6H12来研究Cr(CO)5的瞬态红外光谱。 相似文献
975.
Jin Wu Lingku Chang Wenbo Li Lixia Zheng Weifeng Sun 《Analog Integrated Circuits and Signal Processing》2017,90(3):513-521
This paper presents a CMOS voltage controlled ring oscillator with temperature compensation for low power time-to-digital converters (TDCs). In order to maintain the oscillation frequency stable, a novel compensation circuit is proposed through adaptively sensing temperature variations. This design has been implemented in TSMC 0.35 μm CMOS standard process with an active area of under 0.039 mm2. Experimental results show that the clock frequency is around 159.0 MHz only with a power consumption of 550 μA. As respective to the room temperature the maximum frequency variation is between ?3.46 and +3.08 % under temperature range of ?40 to 85 °C. The bit error time induced by clock jitter is limited within 4.8 % in the whole clock period, and the differential nonlinearity of the TDC is less than 0.408 LSB. 相似文献
976.
977.
Wearable,Healable, and Adhesive Epidermal Sensors Assembled from Mussel‐Inspired Conductive Hybrid Hydrogel Framework 下载免费PDF全文
Meihong Liao Pengbo Wan Jiangru Wen Min Gong Xiaoxuan Wu Yonggang Wang Rui Shi Liqun Zhang 《Advanced functional materials》2017,27(48)
Healable, adhesive, wearable, and soft human‐motion sensors for ultrasensitive human–machine interaction and healthcare monitoring are successfully assembled from conductive and human‐friendly hybrid hydrogels with reliable self‐healing capability and robust self‐adhesiveness. The conductive, healable, and self‐adhesive hybrid network hydrogels are prepared from the delicate conformal coating of conductive functionalized single‐wall carbon nanotube (FSWCNT) networks by dynamic supramolecular cross‐linking among FSWCNT, biocompatible polyvinyl alcohol, and polydopamine. They exhibit fast self‐healing ability (within 2 s), high self‐healing efficiency (99%), and robust adhesiveness, and can be assembled as healable, adhesive, and soft human‐motion sensors with tunable conducting channels of pores for ions and framework for electrons for real time and accurate detection of both large‐scale and tiny human activities (including bending and relaxing of fingers, walking, chewing, and pulse). Furthermore, the soft human‐motion sensors can be enabled to wirelessly monitor the human activities by coupling to a wireless transmitter. Additionally, the in vitro cytotoxicity results suggest that the hydrogels show no cytotoxicity and can facilitate cell attachment and proliferation. Thus, the healable, adhesive, wearable, and soft human‐motion sensors have promising potential in various wearable, wireless, and soft electronics for human–machine interfaces, human activity monitoring, personal healthcare diagnosis, and therapy. 相似文献
978.
Lin Yang Shiwei Ye Zhibo Wang Zhipei Huang Jiankang Wu Yongmei Kong Li Zhang 《半导体学报》2017,38(10):105004-8
A wearable micro-sensor motion capture system with 16 IMUs and an error-compensatory complementary filter algorithm for real-time motion estimation has been developed to acquire accurate 3D orientation and displacement in real life activities. In the proposed filter algorithm, the gyroscope bias error, orientation error and magnetic disturbance error are estimated and compensated, significantly reducing the orientation estimation error due to sensor noise and drift. Displacement estimation, especially for activities such as jumping, has been the challenge in micro-sensor motion capture. An adaptive gait phase detection algorithm has been developed to accommodate accurate displacement estimation in different types of activities. The performance of this system is benchmarked with respect to the results of VICON optical capture system. The experimental results have demonstrated effectiveness of the system in daily activities tracking, with estimation error 0.16 ±0.06 m for normal walking and 0.13 ±0.11 m for jumping motions. 相似文献
979.
Chao Xie Xing‐Tong Lu Xiao‐Wei Tong Zhi‐Xiang Zhang Feng‐Xia Liang Lin Liang Lin‐Bao Luo Yu‐Cheng Wu 《Advanced functional materials》2019,29(9)
Due to its significant applications in many relevant fields, light detection in the solar‐blind deep‐ultraviolet (DUV) wavelength region is a subject of great interest for both scientific and industrial communities. The rapid advances in preparing high‐quality ultrawide‐bandgap (UWBG) semiconductors have enabled the realization of various high‐performance DUV photodetectors (DUVPDs) with different geometries, which provide an avenue for circumventing numerous disadvantages in traditional DUV detectors. This article presents a comprehensive review of the applications of inorganic UWBG semiconductors for solar‐blind DUV light detection in the past several decades. Different kinds of DUVPDs, which are based on varied UWBG semiconductors including Ga2O3, MgxZn1?xO, III‐nitride compounds (AlxGa1?xN/AlN and BN), diamond, etc., and operate on different working principles, are introduced and discussed systematically. Some emerging techniques to optimize device performance are addressed as well. Finally, the existing techniques are summarized and future challenges are proposed in order to shed light on development in this critical research field. 相似文献
980.
Zhuo Kang Huijing Guo Jing Wu Xu Sun Zheng Zhang Qingliang Liao Suicai Zhang Haonan Si Pingwei Wu Li Wang Yue Zhang 《Advanced functional materials》2019,29(9)
The simultaneous and efficient evolution of hydrogen and oxygen with earth‐abundant, highly active, and robust bifunctional electrocatalysts is a significant concern in water splitting. Herein, non‐noble metal‐based Ni–Co–S bifunctional catalysts with tunable stoichiometry and morphology are realized. The engineering of electronic structure and subsequent morphological design synergistically contributes to significantly elevated electrocatalytic performance. Stable overpotentials (η10) of 243 mV (vs reversible hydrogen electrode) for oxygen evolution reaction (OER) and 80 mV for hydrogen evolution reaction (HER), as well as Tafel slopes of 54.9 mV dec?1 for OER and 58.5 mV dec?1 for HER, are demonstrated. In addition, density functional theory calculations are performed to determine the optimal electronic structure via the electron density differences to verify the enhanced OER activity is related to the Co top site on the (110) surface. Moreover, the tandem bifunctional NiCo2S4 exhibit a required voltage of 1.58 V (J = 10 mA cm?2) for simultaneous OER and HER, and no obvious performance decay is observed after 72 h. When integrated with a GaAs solar cell, the resulting photoassisted water splitting electrolyzer shows a certified solar‐to‐hydrogen efficiency of up to 18.01%, further demonstrating the feasibility of engineering protocols and the promising potential of bifunctional NiCo2S4 for large‐scale overall water splitting. 相似文献