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11.
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   
12.
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   
13.
The outreach program in the University of Otago Chemistry Department, focus in the FACS Chemical Education Award Lecture, has been running for more than 10 years. Over that time, it has worked in schools around New Zealand as well as delivering workshops at the Madam Curie High School Chemistry Camp in Taiwan and partnerships with a number of teacher training institutes in Malaysia. In addition to supporting schools and teachers in their chemistry teaching. The program also develops a wide range of skills and attitudes among the chemistry student volunteers who work delivering hands on activities. An overview of the program, the approach taken, and some examples of the activities will be followed by results of student interviews as they reflect on their development and learning.  相似文献   
14.
The efficient synthesis of 6H-benzo[c]chromen-6-one and dibenzo[c,h]chromen-6-one derivatives is described. Thus, treatment of arenediynes 1 and enediynes 5 with 5?mol % Ph3PAuCl and 10?mol % of AgSbF6 in refluxing toluene gave dibenzo[c,h]chromen-6-ones 4 and 6H-benzo[c]chromen-6-ones 6, in good yields, respectively.  相似文献   
15.
Two novel 6,7-secoeunicellins, cladieunicellins W (1) and X (2), along with a known eunicellin, klymollin Y (3), were isolated from an octocoral identified as Cladiella sp. The structures of secoeunicellins 1 and 2 were elucidated by spectroscopic methods. 1 is the first secoeunicellin possessing a γ-lactone ring and 2 represents the first secoeunicellin possessing two tetrahydrofuran moieties. Secoeunicellin 2 displayed significant inhibitory effects on the generation of superoxide anions and the release of elastase. These results implied that the methoxy group at C-6 in 2 plays an important role in determining the activity of these compounds.  相似文献   
16.
台湾的植物生物多样性及其特点之探讨   总被引:6,自引:0,他引:6  
在物种多样性、生态系统多样性和遗传多样性三个层面上,探讨了台湾植物生物多样性的现状;在分析台湾植物生物多样性及与周边地区比较的基础上,从多个方面对其特点作了探讨,并对台湾与大陆在植物生物多样性方面的亲缘性作了阐明。  相似文献   
17.
An automatic station for soil gas monitoring was set up on an active fault zone of SW Taiwan. After more than one year of continuous measurements, some spike-like anomalous high radon and thoron concentrations could be observed. A similar soil radon spectrum was also obtained from an independent monitoring station, which was only 100 m away. These anomalous peaks usually occurred a few days or weeks before the earthquakes (ML4.5). This indicates that variations of both soil radon and thoron can serve as useful tools for earthquake surveillance, esp. at fault zones.  相似文献   
18.
New polysubstituted N-arylpyrazole derivatives were synthesized from N1-arylsydnone with acetylene and boronic acid, including 2-thiophenyl, 3-thiophenyl, 2-benzo[b]thiophenyl, or dibenzothiophenyl-4-boronic acid, via 1,3-dipolar cycloaddition and Suzuki coupling reaction. Based on the growth inhibitory activity results against lung carcinoma (NCI-H226), nasopharyngeal (NPC-TW01), and T-cell leukemia (Jurkat) cancer cells, compounds 5d and 7d with dibenzothiophenyl bioisostere possessed the significant inhibitory activity for NPC-TW01 (32 μM and 16 μM) and NCI-H226 (16 μM and 8.9 μM), respectively.  相似文献   
19.
Zuhao Zhu 《Analytical letters》2017,50(9):1422-1434
A novel and automated flow injection (FI) system using a commercially available anion-exchange resin was developed for the online determination of rhenium in seawater by inductively coupled plasma–mass spectrometry (ICP–MS). The flow rate, reagent concentration, and sample volume were optimized. The rhenium concentration was determined using the integrated peak area through interpolation of standard addition calibration curves. The relative standard deviation was less than 2.45% (n?=?5), the recoveries were from 94.59 to 104.11%, and the linear dynamic range of the method was up to 998?ng?kg?1. There was a good agreement between the rhenium concentrations in a standard measured in this work with results from previous studies. The limit of detection was 0.11?ng?kg?1 for a sample volume of 7.5?mL and one cycle required 8.33?min. The developed FI–ICP–MS method was used to determine rhenium in seawater from the Jiulong River Estuary and Taiwan Strait.  相似文献   
20.
Archaeological finds of Neolithic to Iron Age pottery show clay potsherds characterized by red cord‐markings. The items date back from 5500 to 1500 B.P. To better understand temporal changes in the provenance of raw‐material sources, and the nature of materials used in the red colorant and ceramic bodies, micro‐Raman spectroscopy, X‐ray diffraction analysis (XRD), and micro X‐ray florescence spectroscopy (μXRF) were applied to 29 red‐coated potsherd samples found at twelve archaeological sites across Taiwan. The techniques identified the chemical and mineralogical composition of the red coatings and ceramic bodies as well as the production methods of ancient potters. Eighteen mineral phases were identified from the Raman spectra, including hematite, α‐quartz, and anatase. Feldspar, rutile, pyroxenes, calcite, gypsum, amorphous carbon, and graphite were also detected. XRD measurements, and μXRF analyses were used as complementary techniques to obtain mineral and chemical compositions. Hematite, anatase, calcite, plagioclase feldspar, and illite were present in potsherds, suggesting pottery produced from illitic clays fired at less than 850 °C under oxidizing conditions. Results further suggest that raw materials were sourced from or near local volcanic rock areas, and more broadly from metamorphic or sedimentary rocks and clays. Chemically, raw materials used for red coatings are different to those of the ceramic bodies. Objects from most sites used the same raw material sources; however, some sites contain objects made from changing sources over time. Pot coatings exhibit polygonal cracks, and loosened cementation strongly suggesting that finely processed moist clays were fired to a biscuit form with no second stage firing process. The non‐destructive Raman experiments identified and characterized mineral phases, which helped understand manufacturing techniques. Overall the multi‐technique approach gave extensive information on the finds, helping to differentiate raw material sources and production technologies. This approach is an important and effective method for investigating archaeological finds. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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