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81.
金属卤化物气体放电灯启动问题的探讨 总被引:6,自引:0,他引:6
本文介绍了分别改变灯内填充物含量即 NaI 和 ScI 含量的方法,探讨此变化与光源气体放电参数的关系,从而分析和研究金属卤化物灯的启动特性,从而寻求延长光源寿命的途径。 相似文献
82.
本文报道了钽掺杂钌基厚膜电阻制备过程中导电相和玻璃相颗粒尺寸效应的实验研究结果。当导电相和玻璃相颗粒尺寸分别达到25和50nm时,电阻阻值和电阻温度系数也随之发生显著变化,并尝试根据厚膜电阻导电机理对其产生的原因进行定性的分析。 相似文献
83.
Peicheng Ju Suyama K. Ferguson P.F. Jr. Wai Lee 《Solid-State Circuits, IEEE Journal of》1995,30(12):1316-1325
A time- and capacitor-multiplexing technique for use in a highly linear switched-capacitor multibit DAC in sigma-delta data converters is presented. The technique uses subintervals in the sample clock to deliver multiple charge packets to holding capacitors. It avoids distortion effects caused by mismatched capacitors and finite opamp gain. A five-level switched-capacitor DAC using the proposed technique was designed as part of an audio-band multibit sigma-delta D/A converter that achieved a dynamic range of 92 dB and a THD of -93 dB with a low oversampling ratio of 32. No trimming, calibration, or dynamic matching scheme was required. The five-level SC DAC has been fabricated in a 2-μm CMOS process, and testing confirmed the anticipated theoretical results 相似文献
84.
Ju T.H. Lin W. Lee Y.C. McKnight D.J. Johnson K.M. 《Photonics Technology Letters, IEEE》1995,7(9):1010-1012
A self-pulling soldering technology has been demonstrated for assembling liquid crystal on silicon (LCOS) spatial light modulators (SLMs). Solder joints with different profiles and sizes are designed to provide vertical surface tension forces to control the gap accommodating the ferroelectric liquid crystal (FLC) layer in the range of a micron with sub-micron uniformity. This technology provides an automatic, batch assembly process for a LCOS SLM through one reflow process. The component designs and process optimization are described, and the first operational results are presented 相似文献
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87.
对2005年度发表的中文石油科技期刊论文被EI收录的情况进行了检索、统计与分析。共有13种中文石油期刊发表的2514篇论文被EI Compendex Web收录,其中《天然气工业》、《钻采工艺》、《油气井测试》和《石油学报(石油加工)》4种期刊上发表的1064篇论文被EI核心收录。EI收录论文总数和核心收录论文篇数均创历年新高,表明我国石油科技论文的水平进一步提高。但是,与高达77种之多的庞大的中文石油科技期刊群和每年数以万计的中文石油科技论文产出量相比,EI所收录的中文石油科技期刊种数和论文篇数仍处于较低水平。 相似文献
88.
Dae‐Sik Lee Hyoung Gil Choi Kwang Hyo Chung Bun Yeoul Lee Hyeon‐Bong Pyo Hyun C. Yoon 《ETRI Journal》2007,29(5):667-669
This letter presents a smart integrated microfluidic device which can be applied to actively immobilize proteins on demand. The active component in the device is a temperature‐controllable microelectrode array with a smart polymer film, poly(N‐isopropylacrylamide) (PNIPAAm) which can be thermally switched between hydrophilic and hydrophobic states. It is integrated into a micro hot diaphragm having an integrated micro heater and temperature sensors on a 2‐micrometer‐thick silicon oxide/silicon nitride/silicon oxide (O/N/O) template. Only 36 mW is required to heat the large template area of 2 mm×16 mm to 40°C within 1 second. To relay the stimulus‐response activity to the microelectrode surface, the interface is modified with a smart polymer. For a model biomolecular affinity test, an anti‐6‐(2, 4‐dinitrophenyl) aminohexanoic acid (DNP) antibody protein immobilization on the microelectrodes is demonstrated by fluorescence patterns. 相似文献
89.
Photoinduced Proton Transfer between Photoacid and pH‐Sensitive Dyes: Influence Factors and Application for Visible‐Light‐Responsive Rewritable Paper 下载免费PDF全文
Ting Zhang Lan Sheng Junning Liu Le Ju Jianhua Li Zhen Du Weiran Zhang Minjie Li Sean Xiao‐An Zhang 《Advanced functional materials》2018,28(16)
Ink‐free printing based on rewritable paper is an efficient and environmental friendly way to reuse paper, protect resources, and save energy for sustainable development of human society. Among various kinds of rewritable media, light responsive rewritable paper (LRP) is one of the most popular research areas due to its clean and favorable noncontact writing. Visible light is more suitable for LRP for its superior penetration and much less damages to organic molecules than UV light. However, visible‐light‐responsive rewritable paper (VLRP) has only limited successes so far. Herein, a VLRP is newly designed and fabricated based on photoinduced proton transfer (PPT) between photoacid and pH‐sensitive dyes. Success of it is highly benefited from systematical investigation and in‐depth understanding on the key influence factors, such as concentration‐induced undesired isomerization, temperature, humidity, and light intensity, on the PPT and its inverse process. As‐prepared VLRP shows long‐awaited properties, such as, high color contrast and resolution, appropriate legible time of prints, excellent reversibility (>100 cycles), easiness to achieve multicolor prints, and agreeing well with environmental concept of green printing. In addition, study of influence factors on PPT in this work, to some extent, may also help people understand complex photocycle process in biosystem. 相似文献
90.
Satoshi Hiroi Seongho Choi Shunsuke Nishino Okkyun Seo Yanna Chen Osami Sakata Tsunehiro Takeuchi 《Journal of Electronic Materials》2018,47(6):3113-3118
To gain deep insight into the mechanism of phonon scattering at grain boundaries, we investigated the boundary thermal resistance by using picosecond pulsed-laser time-domain thermoreflectance for epitaxially grown W/Fe2VAl/W films. By using radio-frequency magnetron sputtering, we prepared a series of the three-layer films whose Fe2VAl thickness ranged from 1 nm to 37 nm. The fine oscillation of reflectivity associated with the top W layer clearly appeared in synchrotron x-ray reflectivity measurements, indicating a less obvious mixture of elements at the boundary. The areal heat diffusion time, obtained from the time-domain thermoreflectance signal in the rear-heating front-detection configuration, reduced rapidly in samples whose Fe2VAl layer was thinner than 15 nm. The ~ 10% mismatch in lattice constant between Fe2VAl and W naturally produced the randomly distributed lattice stress near the boundary, causing an effective increase of boundary thermal resistance in the thick samples, but the stress became homogeneous in the thinner layers, which reduced the scattering probability of phonons. 相似文献