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排序方式: 共有491条查询结果,搜索用时 15 毫秒
1.
本文摘要介绍了河北省白沟镇双向网络服务功能及网络规划设计的理念,重点讲述了反向上行通道的设计、调试及经验数值和采用设备。 相似文献
2.
两种波长激光血管内照射生物效应比较 总被引:2,自引:0,他引:2
目的:研究同等照射条件的低强度532nm与633nm激光血管内照射生物效应的特点。方法:用532nm和633nm激光对健康大耳白家兔血管内照射,平均照射功率均设定在5mW左右,照射总能量约12J。两组家兔均于照前及照后1d、4d、7d、11d采集外周血,检测血浆ET、NO、MDA含量和SOD活性。结果:两组家兔上述各指标随照后时间的变化规律相似,经方差分析组间各指标都没有显著性差异。结论:同等照射条件下,低强度532nm与633nm激光照射血液的生物效应相似。 相似文献
3.
从主体树脂的结构设计、单体的合成工艺、主体树脂的合成工艺、光致产酸剂的评价、配方研究等多个方面论述了193nm光刻胶的研制工艺,合成出了多种适用的单体及多种结构的主体树脂,进行了大量的配方研究,筛选出了最佳配方.研制出的样品经美国SEMATECH实验室应用评价其最佳分辨率为0.1μm,最小曝光量为26mJ/cm^2,不但具有优异的分辨率和光敏性,而且还具有良好的粘附性和抗干法腐蚀性. 相似文献
4.
248nm深紫外光刻胶 总被引:11,自引:3,他引:11
本文从化学增幅技术的产生,深紫外248nm胶主体树脂及PAG发展历程、溶解抑制剂、存在的工艺问题及解决途径多个方面综述了深紫外248nm胶的发展与进步. 相似文献
5.
本文以对氯苯酚(4-cP)、对硝基苯酚(4-NP)和罗丹明B(RhB)为模型有机物(以4-CP和4-NP为小分子模型有机物,以RhB为大分子模型有机物),分别研究了185nmUV对水中这3种模型有机物的降解规律、性能和效果.研究结果表明,185nmUV直接对水中4-CP、4-NP和RhB有很好的降解效果.研究内容包括:185nmUV降解模型有机物的浓度、TOC(Totalorganic carbon)浓度、185nmUV降解模型有机物过程中溶液pH及电导率变化、以及降解模型有机物过程中产生的无机离子等几个方面. 相似文献
6.
HUANG Ru WU HanMing KANG JinFeng XIAO DeYuan SHI XueLong AN Xia TIAN Yu WANG RunSheng ZHANG LiangLiang ZHANG Xing & WANG YangYuan 《中国科学F辑(英文版)》2009,(9):1491-1533
It is predicted that CMOS technology will probably enter into 22 nm node around 2012. Scaling of CMOS logic technology from 32 to 22 nm node meets more critical issues and needs some significant changes of the technology, as well as integration of the advanced processes. This paper will review the key processing technologies which can be potentially integrated into 22 nm and beyond technology nodes, including double patterning technology with high NA water immersion lithography and EUV lithography, new devi... 相似文献
7.
Pille Mänd Lea Hallik Josep Peñuelas Pierpaolo Duce Claus Beier János Garadnai Inger Kappel Schmidt Patricia Prieto Joke W. Westerveld 《Remote sensing of environment》2010,114(3):626-297
The aim of this study was to evaluate the use of ground-based canopy reflectance measurements to detect changes in physiology and structure of vegetation in response to experimental warming and drought treatment at six European shrublands located along a North-South climatic gradient. We measured canopy reflectance, effective green leaf area index (green LAIe) and chlorophyll fluorescence of dominant species. The treatment effects on green LAIe varied among sites. We calculated three reflectance indices: photochemical reflectance index PRI [531 nm; 570 nm], normalized difference vegetation index NDVI680 [780 nm; 680 nm] using red spectral region, and NDVI570 [780 nm; 570 nm] using the same green spectral region as PRI. All three reflectance indices were significantly related to green LAIe and were able to detect changes in shrubland vegetation among treatments. In general warming treatment increased PRI and drought treatment reduced NDVI values. The significant treatment effect on photochemical efficiency of plants detected with PRI could not be detected by fluorescence measurements. However, we found canopy level measured PRI to be very sensitive to soil reflectance properties especially in vegetation areas with low green LAIe. As both soil reflectance and LAI varied between northern and southern sites it is problematic to draw universal conclusions of climate-derived changes in all vegetation types based merely on PRI measurements. We propose that canopy level PRI measurements can be more useful in areas of dense vegetation and dark soils. 相似文献
8.
In order to study the donor ability of ferrocenylimines as directing ortho metalation group(DMG) to lithium alkylide to prepare planar chiral ferrocene, a series of ferrocenyl schiff bases were synthesized by new methods using molecular sieves(0.4nm) and AlCl3 as catalysts. The reaction periods were reduced using these two catalysts in contrast with Al2O3, which was a traditional method used in the literature. In addition, as an important feature of these schiff bases, we found that they were unstable as oils in air or when filtrated through silica gel, but were stable as solids. The structures of the new compounds were confirmed by IR, ^1H NMR and HRMS. 相似文献
9.
10.
This paper presents a new method and results from measurement of internal parameters of programmable nanoscale circuits, namely Xilinx FPGA devices and especially Zynq SoC devices designed on 28 nm TSMC’s technology and older 45 nm Spartan 6 device as well as Xilinx Virtex product lines. The method utilizes a new undersampling approach for frequency measurement and an easy way of processing BRAM data streams. The proposed flexible circuits have been used in various measurements of timing parameters and delays in FPGAs, including measurements or detection of the aging issues. The paper presents results of measurements under various core voltage values as performed on selected Xilinx FPGA platforms, including key results about limited usability of the latest 28 nm devices under accelerated conditions and possibility of studying or mitigating aging effects in FPGAs. The paper presents rare results of experiments, real measurements and data available from current as well as previous technology nodes and it attempts to uncover new facts and areas of the latest high-end technologies, including the area of aging and degradation processes in general. The new methodology, presented approach and results can also be used in various dependable systems, including selected aerospace, medical, automotive or transportation ones. It is also directly and easily applicable to modern processor and multicore systems. 相似文献