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1.
L. Marini  R. Cioni 《Geothermics》1985,14(1):29-34
Chloride concentrations and pressures (or temperatures) in two points of a geothermal test line have been used to determine the enthalpy of the steam/water mixture discharged from Nisyros I geothermal well (Greece). The results are in agreement with those obtained by the Russell James method. The chloride method described in this paper is fast, requires cheap, portable equipment and is thus particularly suitable for short-term well testing during drilling or immediately after well completion, especially in steam-rich mixtures.  相似文献   
2.
Photosynthetic microorganisms are expected to be useful to maintain an oxygenic atmosphere and to provide biomass for astronauts in the International Space Station as well as in future long-term space flights. However, fluxes of complex ionizing radiation of various intensities and energies make space an extreme environment for the microorganisms, affecting their photosynthetic efficiency. To automatically monitor the photosynthetic Photosystem II (PSII) activity of microorganisms under space conditions an optical biosensor, which utilizes chlorophyll fluorescence as biological transduction system, was built; the PSII activity was monitored by the biosensor during balloon flights at stratospheric altitudes of about 40 km. The effect of space stress on quantum yield of PSII varied among the tested species depending on the growth light conditions at which they were exposed during the flights.  相似文献   
3.
位于我国西北部的新疆维吾尔自治区在多民族融合交流下形成了独特的人文环境,“袷袢”作为新疆多个民族传统服装款式之一,依据其款式、色彩及装饰风格各民族袷袢特点各异。通过研究新疆地区传统民族服饰“袷袢”与不同民族间的差异性,从中了解各民族间在服饰文化中的相互交融与影响,研究“袷袢”这一典型性民族服饰在文化交融中的共性与特性,从而更准确地认知民族服饰的文化功能,及中华民族多元一体格局下的服饰文化与审美趋向。  相似文献   
4.
An innovative receiver architecture for the satellite‐based automatic identification system has been recently proposed. In this paper, we describe a few modifications that can be introduced on the algorithms for synchronization and detection, which provide an impressive performance improvement. The receiver architecture has been designed for an on‐board implementation, and a prototype has been implemented by the University of Parma and CGS S.p.A. Compagnia Generale per lo Spazio under the European Space Agency project FENICE (Flexible innovative AIS receiver prototype). A few modifications are also here described that could allow a further performance improvement in case of processing moved to ground‐based stations, based on a priori information there available. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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The increasing use of spark chambers for detecting cosmic gamma rays (SAS-B, COS-B, S-133, Mi-Sa Gamma) justifies a comprehensive study of data analysis procedures.  相似文献   
7.
Preliminary laboratory tests carried out on 20 mineral waters indicate that the infrared (IR) method for the determination of total dissolved inorganic carbon (TDIC) is more accurate than the pH-alkalinity method, especially for high-TDIC, naturally sparkling waters and low-TDIC waters. The results of the two analytical methods are similar for mineral waters whose TDIC ranges from 100 to 500 mg/L as HCO3, suggesting a relative accuracy of 0.3–2.9%. The limit of detection (LOD) of the IR method is close to 10 mg HCO3/L and independent of pH. This value is comparable with the LOD of the pH-alkalinity method in the pH range 6.5–9 whereas the LOD of the latter increases strongly with decreasing pH below pH 6.5. The IR method is quick, since a run takes a few minutes and, on average, 10 analyses are carried out in an hour, including the time spent for clean up and preparation between samples. It constitutes a sound alternative to the pH-alkalinity technique for the field measurement of TDIC in geothermal and other natural waters.  相似文献   
8.
In this paper, we study the performance of telecommand space links affected by pulsed, continuous wave and pseudo‐noise jamming. Countermeasures include coding, interleaving, and direct sequence spread spectrum. Binary and non‐binary low‐density parity‐check codes, parallel turbo codes, and soft‐decision decoded BCH codes are considered. We investigate the impact of different decoding algorithms, also taking into account the role of jamming state information, spreading processing gain and interleaving. The results show that significant gains (up to more than 10 dB) can be achieved in a number of interesting scenarios. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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The chemical derivatization of biologically active microbial metabolites continues to be a promising approach to the identification of new drugs. We recently synthesized the novel antiproliferative compound SDZ 281-977, 5-[2-(2,5-dimethoxy-phenyl)ethyl]-2-hydroxy-benzoic acid methylester, a derivative of the EGF receptor tyrosine kinase inhibitor lavendustin A. Here we report on our studies of the anticancer efficacy and the mode of action of SDZ 281-977. The growth of both the human pancreatic tumor cells MIA PaCa-2 and the human vulvar carcinoma cells A431 was inhibited in the low micromolar range. Tumors from these cells were induced in nude mice and were shown to respond to orally or intravenously administered SDZ 281-977. In contrast, no antitumor effect was detected in rats bearing dimethylbenzanthracene-induced mammary tumors. Studies in mice indicated that SDZ 281-977 was neither immunosuppressive nor hematosuppressive at doses effectively inhibiting tumor growth. Surprisingly, the mode of action of SDZ 281-977 apparently does not involve inhibition of EGF receptor tryosine kinase, because, in contrast to lavendustin A, SDZ 281-977 failed to inhibit this enzyme in a cell-free assay. The mechanism of the antiproliferative effect can be explained on a cellular level by the ability of the compound to arrest cells in mitosis. SDZ 281-977 is thus the first example of an antimitotic agent derived from the potent tyrosine kinase inhibitor lavendustin A. The therapeutic potential of SDZ 281-977 is enhanced by the fact that it is not subject to multidrug resistance, because tumor cells expressing the multidrug resistance phenotype were as sensitive to SDZ 281-977 as their nonresistant counterparts. In conclusion, SDZ 281-977 represents a novel lavendustin A derivative with potent antiproliferative properties in vitro and in vivo that may be explained on the basis of its antimitotic effects. SDZ 281-977 may be a candidate drug for the treatment of selected cancers, including those expressing the multidrug resistance phenotype.  相似文献   
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