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1.
During the last 20 years, beamline BL08B has been upgraded step by step from a photon beam‐position monitor (BPM) to a testing beamline and a single‐grating beamline that enables experiments to record X‐ray photo‐emission spectra (XPS) and X‐ray absorption spectra (XAS) for research in solar physics, organic semiconductor materials and spinel oxides, with soft X‐ray photon energies in the range 300–1000 eV. Demands for photon energy to extend to the extreme ultraviolet region for applications in nano‐fabrication and topological thin films are increasing. The basic spherical‐grating monochromator beamline was again upgraded by adding a second grating that delivers photons of energy from 80 to 420 eV. Four end‐stations were designed for experiments with XPS, XAS, interstellar photoprocess systems (IPS) and extreme‐ultraviolet lithography (EUVL) in the scheduled beam time. The data from these experiments show a large count rate in core levels probed and excellent statistics on background normalization in the L‐edge adsorption spectrum.  相似文献   
2.
台商对大陆投资区位选择受地区市场因素、集聚因素、劳动力因素及基础设施基本政策等因素的影响.研究利用1995年至2007年台商投资区位选择的面板数据,首先验证了台商投资区位选择受到经济规模、区域开放程度、台商集聚度、劳动成本等关键因素的影响;并在此基础上,采用变系数面板数据模型重点分析了影响因素的时变特征.主要结论包括:外贸依存度指标的变化表现了台商投资由向外出口产品的模式逐渐转向在国内市场销售的模式;区域资金配套能力表明台商企业近些年呈现了对当地资金配套的需求;集聚因素影响显著性极高,说明台资企业的集聚现象非常显著,这与当前实际发展情况相似;劳动力因素结果说明台商对于劳动力的关注已从劳动力成本向劳动力质量转变等等.这些因素的时变特征,对台商投资大陆区位选择的行为是具有较强的解释力度.  相似文献   
3.
The unique selective estrogen receptor modulator, Raloxifene (1), and antitubulin agent 2 were synthesized through the key intermediate, 4-methoxybenzyl 2-bromo-4-methoxyphenyl sulfoxide (6), respectively. It was found that compared with the o-sulfanyl aryl bromides, the sulfinyl group at ortho position accelerated the Sonogashira coupling reaction of aryl bromides. Thus, compound 6 was coupled with 3,4,5-trimethoxyphenyl acetylene, followed by mercury-catalyzed cyclization reaction afford compound 2 in 79% overall yield. Raloxifene (1) was prepared from compound 6 in four steps and 33% overall yield via coupling reaction with 1-trimethylsily-2-(4-tert-butyldimethylsiloxy)phenylethyne, mercury-catalyzed cyclization reaction, alkylation and demethylation.  相似文献   
4.
舟山渔场的水温分布特征分析   总被引:2,自引:0,他引:2  
通过调查测得的数据分析了渔场水温的分布概况, 结果发现: 水平分布上, 无论冬夏, 渔场中北部始终存在1个低温区, 台湾暖流处(位置冬季偏东, 夏季偏西, 平均位置在124°E附近)存在高温水舌指向偏北, 冷暖水系交汇明显; 垂直分布上, 由于渔场岛屿众多, 海水混合作用强烈, 水温垂直梯度终年都很微弱, 即使在盛夏也很难形成强大的跃层.  相似文献   
5.
This study assessed elemental concentrations in the serum of 154 preschool children in central Taiwan via instrumental neutron activation analysis (INAA). A total of eight elements, Br, C1, Fe, Na, Rb, Sc, Se and Zn of sera for Taiwanese preschool children living at four residential areas: Taichung city, Taichung urban townships and in a remote area inhabited by two groups of aborigines, Atayal and Bunun were determined. Standard reference materials (tomato leaves, NIST-SRM 1570a, and lichen, IAEA-336) were used as quality control standards to crosscheck the accuracy. Residential area, socioeconomic status and gender were shown to significantly influence serum levels of the eight trace elements. Statistical analysis revealed several different gender patterns via the two-tailed student's test. A quantified index of agreement (AT) was used to classify these elements. Small AT indicated a close consistency, while large AT indicated a larger fluctuation, or less agreement, such that the correlation between the elements could be interpreted using a series of quantified indices at the serum levels of preschool children.  相似文献   
6.
A magnetooptical study of some halogenotertiobutylphosphines is performed in order to improve the so-called regular relationship which seemed to exist between the magnetic rotation, ?dP, of the lone pair and the bond angles in PX3 compounds. It is clearly shown that, in any case, ?dP is largely lower than the extreme value which was observed in PX3 molecules for which XPX=100°. Thus, the existence of the previously invoked relationship vanishes and the question remains as to why there exists a maximum of ?dP for XPX of 100°.  相似文献   
7.
8.
A general approach toward the synthesis of multi-functionalized diazapentacene derivatives 1, using 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadiene (TDCp, 2), a substituted benzene-1,2-diamine (ADA, 6), and a naphthalene-1,4-dione (BQ, 3) as the building units, is described. The synthesis basically entails three operations: (i) oxidation of the dichloroetheno-bridge in the Diels-Alder cycloadduct 4 of TDCp and 3, (ii) condensation of the 1,2-diketone 5 thus generated with an ADA to give quinoxaline-fused polycyclic compounds 7, followed by (iii) an one-pot, three-reaction process keyed upon the base- or acid-catalyzed aromatization-driven Grob-type fragmentation to produce quinoxaline ring-embedded diazapentaceneesters 1. The diazapentacene derivative 1a underwent the nucleophilic aromatic ipso-amination with primary and secondary amines to afford the amino-substituted derivatives 12, which tend to self-assemble in solid state driven by the cofacial π-stacking interactions, demonstrated by the crystal packing structures of 12a and 12f.  相似文献   
9.
Exhalation of radon and its carrier gases in SW Taiwan   总被引:3,自引:0,他引:3  
Gas compositions of mud volcanoes reveal multiple sources for gas exhalation in SW Taiwan. For comparison, two sites, Yan-chao (YC) and Chung-lun (CL), were chosen for measurements of soil Rn concentrations using a portable radon detector. The 222Rn concentrations at the YC site were ca. 5200 Bq/m3. However, the average 222Rn concentrations at the CL site exhibited higher value of ca. 16,800 Bq/m3. With the reference of the gas flux and compositions from the nearby mud pool, the soil 222Rn concentrations are largely controlled by the flux of carrier gases exhaled from deep reservoirs.  相似文献   
10.
随着我国经济快速成长,衍生性金融商品的投资分析,已成为国内财务数学研究热门课题。以股票市场而言,人们总希望比别人早一步掌握行情的脉动,以获取最高的报酬率,然而,影响股市加权股价指数波动的因素众多,要如何进行趋势分析与预测,是很多学者相当感兴趣与研究的主题。本文考虑以模糊统计方法,作模糊时间数列的趋势分析与预测。其望应用模糊统计分析方法比传统的时间数列分析方法能得到更合理的解释,且预测结果可以提供决策者更多的信息,做出正确的决策。最后以台湾地区加权股票指数为例,做一实证上的详细探讨。  相似文献   
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