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101.
102.
文章简述了光电印制电路板中聚合物光波导层的制作应该遵循的原则,介绍了光波导层的主要成型工艺,包括反应离子蚀刻、平版影印、激光烧蚀和加热模压等方法。 相似文献
103.
104.
国内正在崛起的新型电池 总被引:2,自引:0,他引:2
我国电池产量居世界首位, 但其中产量的90% 以上为低档次电池。近10多年来, 我国新型电池的生产引人注目。其中有碱性锌锰电池、锂一次电池及小型可充电镉镍电池、氢镍电池和锂离子电池。介绍了国内正在崛起的几种新型电池。 相似文献
105.
106.
This paper presents two new approaches used in the secondary ion mass spectrometry (SIMS) for high sensitivity dopant and
impurity analysis in HgCdTe materials, namely, the high mass resolution with dynamic transfer and the MCs+ technique. It is shown that better detection limits for As and Cu can be obtained at a level of 2–5e14 at/cm3. The MCs+ technique has added advantages of better measurement precision, monitoring Cd composition in the same profile, and small
device area analysis capability. Advantages and trade-offs of each technique are discussed and compared. An updated detection
limit table for all elements measured in HgCdTe materials using SIMS is also presented. 相似文献
107.
This report focuses on research into waveguides prepared by K+-Na+ ion exchange with the help of an electric field, and the subsequent comparison with waveguides prepared by pure thermal ion
exchange. The goals of this work were to determine the characteristics of and to address the technological problems associated
with waveguides prepared in two types of highly pure optical glass: special soda-lime silica GIL49 glass produced from pure
raw materials and commercially prepared borosilicate BK7 glass. An appropriate chemical mixture, KNO3:Ca(NO3)2 in the molar ratio of 41:59, was used as the source of potassium ions. Experiments were conducted at temperatures between
250 and 410°C, and electric field values between 0 and 150 V/mm. The number of modes, depth, profile, and the change in refractive
index (Δn) were measured for samples from each type of glass under various technological conditions. All of these parameters
can be controlled accurately and repeatedly by the electric field. These experiments have also shown that a particular advantage
of these types of pure glass is the low waveguide optical losses (0.1 to 0.2 dB/cm) attainable. 相似文献
108.
Dong Geon Lee Dong Hoe Kim Jae Myeong Lee Byeong Jo Kim Jun Young Kim Seong Sik Shin Hyun Suk Jung 《Advanced functional materials》2021,31(9):2006718
One of the most effective methods to achieve high-performance perovskite solar cells (PSCs) is to employ additives as crystallization agents or to passivate defects. Tri-iodide ion has been known as an efficient additive to improve the crystallinity, grain size, and morphology of perovskite films. However, the generation and control of this tri-iodide ion are challenging. Herein, an efficient method to produce tri-iodide ion in a precursor solution using a photoassisted process for application in PSCs is developed. Results suggest that the tri-iodide ion can be synthesized rapidly when formamidinium iodide (FAI) dissolved isopropyl alcohol (IPA) solution is exposed to LED light. Specifically, the photoassisted FAI–IPA solution facilitates the formation of fine perovskite films with high crystallinity, large grain size, and low trap density, thereby improving the device performance up to 22%. This study demonstrates that the photoassisted process in FAI dissolved IPA solution can be an alternative strategy to fabricate highly efficient PSCs with significantly reduced processing times. 相似文献
109.
Hong-Joon Yoon Dong-Min Lee Young-Jun Kim Sera Jeon Jae-Hwan Jung Sung Soo Kwak Jihye Kim SeongMin Kim Yunseok Kim Sang-Woo Kim 《Advanced functional materials》2021,31(23):2100649
Diverse touch experiences offer a path toward greater human–machine interaction, which is essential for the development of haptic technology. Recent advances in triboelectricity-based touch sensors provide great advantages in terms of cost, simplicity of design, and use of a broader range of materials. Since performance solely relies on the level of contact electrification between materials, triboelectricity-based touch sensors cannot effectively be used to measure the extent of deformation of materials under a given mechanical force. Here, an ion-doped gelatin hydrogel (IGH)-based touch sensor is reported to identify not only contact with an object but also deformation under a certain level of force. Switchable ionic polarization of the gelatin hydrogel is found to be instrumental in allowing for different sensing mechanisms when it is contacted and deformed. The results show that ionic polarization relies on conductivity of the hydrogels. Quantitative studies using voltage sweeps demonstrate that higher ion mobility and shorter Debye length serve to improve the performance of the mechanical stimuli-perceptible sensor. It is successfully demonstrated that this sensor offers dynamic deformation-responsive signals that can be used to control the motion of a miniature car. This study broadens the potential applications for ionic hydrogel-based sensors in a human–machine communication system. 相似文献
110.
Alloy anodes composed of microsized particles receive increasing attention recently, which outperform the nanostructured counterparts in both the manufacturing cost and volumetric energy density. However, the pulverization of particles and fracture of solid electrolyte interphase (SEI) during cycling brings about fast capacity degradation. Herein, it is shown how normally considered fragile SEI can become highly elastic through electrolyte chemistry regulation. Compared to the SEI constructed in classic carbonate electrolyte, the atomic force microscopy tests reveal that the one built in ether-based electrolyte doubles the maximum elastic strain to accommodate the repeated swelling-contracting. Such an SEI effectively encapsulates the microsized Sb anodes to prevent the capacity loss from particle isolation. Coupled with an intercalation-assisted alloying reaction mechanism, a sustained capacity of ≈573 mAh g−1 after 180 cycles at 0.1 A g−1 with outstanding initial Coulombic efficiency is obtained, which is among the highest values achieved in K-ion batteries. This study emphasizes the significance of building robust SEI, which offers the opportunity to enable stable microsized alloy anodes. 相似文献