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41.
基于镜像焦面检测对准标记的套刻性能原位测量技术 总被引:7,自引:2,他引:5
套刻性能是现代高精度步进扫描投影光刻机的重要性能指标之一。提出了一种基于镜像焦面检测对准标记(简称“镜像焦面检测对准标记”)的光刻机套刻性能原位测量技术。该技术通过对曝光在硅片上的镜像焦面检测对准标记图形进行光学对准,利用标记图形对准位置与理想位置偏差实现套刻性能的原位检测。实验结果表明该技术在进行套刻误差的精确测量的同时还可以全面、定量地计算影响光刻机单机套刻误差的场内参量及场间参量。与目前套刻性能原位测量技术相比,该技术有效地避免了测量精度对轴向像质限制的依赖,简化了光刻机整机性能检测的过程。 相似文献
42.
用毛细管色谱内标定量法,同时测定丙烯腈及其合成过程的副产物,此法快捷、方便、具有较高的准确度。 相似文献
43.
44.
This paper describes enantiomer separation using four kinds of chiral stationary phases (CSPs) where quaternary ammonium surfactants containing L-valine diamide moieties into long alkyl chains were bound to silicagel supports by reversed phase liquid chromatography. Our aim was to examine hydrogen bonding association of the chiral moiety in hydrophobic phase brought about by aggregation of the micelle-forming surfactants on the surface. The following CSPs were thus derived from the vinyl-terminated chiral surfactants via hydrosilylation: CSP 1 from N-[3-(10-undecenoyl-L-valylamino)propyl]-N,N,N-trimethylammonium bromide, CSP 2 from N-[6-(10-undecenoyl-L-valylamino)hexyl]-N,N,N-trimethyl-ammonium bromide, CSP 3 from N-[3-(10-undecenoyl-L-valylamino)propyl]-N-octadecanyl-N,N-dimethyl-ammonium bromide and CSP 4 from N-[6-(10-undecenoyl-L-valylamino)hexyl]-N-octadecanyl-N,N-dimethylammonium bromide. The degree of hydrophobicity in the interfacial phase was observed by measuring pyrene fluorescence in aqueous media including an organic modifier. Retention of racemic N-acylleucine isopropyl esters was highest in CSP 4, followed by 3, 2, and 1. Largest alpha values toward enantiomer separation were observed for CSP 4 where the chiral moieties were kept through a hexamethylene unit apart from the polar head groups and to which another long alkyl chain was attached, as compared with those for CSP 4. In CSP 4, the chiral moiety to interact with enantiomeric solutes should be buried into the interfacial phase deeply in more extent than CSP 3. In a similar manner, CSP 2 has more effective for enantiomer separation than CSP 1. The interfacial phase of these CSPs was easily exposed to the bulk phase because of the affinity between the bulk phase and the polar head groups as well as their electrostatic repulsion. However, degree of the enantiomer separation can be controlled by the depth of the chiral moiety in the hydrophobic interfacial phase. 相似文献
45.
温晗秋子 《数学的实践与认识》2003,33(10):1-4
利用因果图模型及其可识别性理论对占座效应 ,即占座行为对座位使用率的影响进行了建模 .并利用这一模型对实际例子中的占座效应进行了分析 ,最终得出占座行为对实例中座位使用率的影响程度 相似文献
46.
机载惯导跑道滑行对准研究 总被引:1,自引:0,他引:1
提出了一种机载惯导系统跑道滑行对准的方案和实施方法,建立了对准时的导航计算和误差补偿迭代方程,研究了影响对准精度的因素和解决的措施。 相似文献
47.
On-line pseudo-dynamic network testing on base-isolated bridges using Internet and wireless Internet 总被引:2,自引:0,他引:2
D -U. Park C -B. Yun J -W. Lee K. Nagata E. Watanabe K. Sugiura 《Experimental Mechanics》2005,45(4):331-343
In this paper we present the results of the online pseudo-dynamic network testing using the Internet that were jointly conducted
by several institutions in Korea and Japan. Example studies were performed on base-isolated bridges with four continous spans.
Test facilities located at several institutions were interactively used to test the non-linear behaviors of the base isolators.
At first, a series of international network tests was carried out between Japan and Korea, and the performance of two system
configurations with different data communication schemes was compared. Then, network tests were repeated on a similar bridge
structure between two institutions in Korea, and the overall performance was discussed. A web-based Java monitoring system
was developed for checking the partners' testing conditions and for sharing the test results with the authorized observers.
Wireless Internet technology using mobile phones was also investigated. The results indicate that the time to execute a single
step varies widely, depending on the data communication/sharing schemes and the testing hardware, e.g., 0.2–15 s for data
communication and 1–10 s for execution of the pseudo-dynamic tests for each time-step. The time required additionally for
data communication in the on-line network testing is judged as reasonable in comparison with the time for the pseudo-dynamic
test. The results also show that the wireless communication is very attractive for on-line network testing, owing to the mobility
and Internet security. 相似文献
48.
张仕清 《数学的实践与认识》2011,41(11)
党政干部公选过程中许多考察指标的边界并不十分明显,评价时无从归类难以形成量化分析结果.运用模糊数学理论建立多目标评价模型,通过构建层次分析法,在对单指标进行评价的基础上,再对所有指标进行综合模糊评价,防止了统计信息的遗漏和中途损失,克服了"满意"、"基本满意"等确定性评价导致的对客观真实的偏离. 相似文献
49.
Ranran Huo Lin Liu Chanika Chanthasa Takuya Okazaki Kazuto Sazawa Kazuharu Sugawara Hideki Kuramitz 《Electroanalysis》2023,35(8):e202200528
A simple electroanalytical method for Cd(II) and Pb(II) detection based on differential pulse anodic stripping voltammetry (DPSV) with in situ prepared antimony-modified glassy carbon rotating disk electrode (in situ Sb-GC-RDE) was developed. The electrochemical detection was performed in a microdroplet (50 μL) of 0.01 M hydrochloric acid that is placed between the electrode surface (top) and a Parafilm®-covered glass slide to maintain a hydrophobic surface (bottom). This method includes a preconcentration process using a membrane filter (MF). The target metal ions were complexed with 1-(2-pyridylazo)-2-naphthol (PAN) as a chelating agent, which was accumulated on the MF via filtration. The RDE microdroplet anodic stripping voltammetry was suitable for the elution and determination of metal ions accumulated on the MF. The in situ preparation of antimony-modified electrode allows the use of common GC electrode with high performance. The detection limits for Cd(II) and Pb(II) were 1.4 and 1.1 μg/L, respectively. The proposed method was successfully used in natural water samples for the simultaneous determination of Cd(II) and Pb(II). 相似文献
50.
A copper-catalyzed aerobic oxidative CN bond cleavage reaction was developed for the synthesis of 4-substituted-NH-1,2,3-triazoles. Diverse β-ketotriazoles derivatives, which are the starting materials for the aerobic oxidative CN bond cleavage reaction, were prepared from nine aryl and seven alkyl alkynes and α-azidoacetophenone by a copper(I)-catalyzed [3 + 2]cycloaddition reaction. The aerobic oxidation of α-(1,2,3-triazol-1-yl)acetophenones using a catalytic amount of copper(II) acetate in the presence oxygen under neutral conditions gave the title compounds in high yield. 相似文献