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We demonstrate that alkali-halide salts, particularly potassium bromide, can reduce the photothermal emission (PTE) from single walled carbon nanotubes (SWNT). PTE is a prominent spectral feature in Raman spectroscopy when a near infrared laser is used to analyze a dark colored sample. We subsequently show that trapping salts inside SWNT and coating SWNT with the salt has a more pronounced impact on not only reducing PTE, but also enhancing the intensity of the Raman spectral features. The effect, which we have called nanotube enhanced Raman spectroscopy (NERS), has differences and similarities to the widely studied surface enhanced Raman spectroscopy (SERS). 相似文献
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J. Parnell 《Journal of Petroleum Geology》1992,15(1):51-70
Thick Permo-Triassic sandstones occur in two basins in Northern Ireland. The sandstones are fluvio-deltaic, including an oolitic facies, and are interbedded with mudrocks. They exhibit petrographic features which are typical of red beds and are widely found in the Permo-Triassic elsewhere in the British Isles. The predominant cements are haematite, potassium feldspar. illite and carbonates. Gypsum, anhydrite and dolomite cements occur in the regions of deepest burial. which represent the basin centres. There was widespread leaching of carbonate/sulphate cements, but calcite is preserved in the oolitic facies and below the sub-Cretaceous (chalk) unconformity. The dissolution of cements and framework grains was due to leaching by meteoric fluids. Precipitation of kaolinite in secondary pores, and subsequent illitization, represent fluctuations in the meteoric hydraulic head. Deep boreholes exhibit sandstone porosities which indicate that there may be significant reservoir potential where adequate seals and traps are present. 相似文献
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KarenParnell 《世界电子元器件》2002,(3):39-40
在英国现在每3分钟就有一部移动电话被盗。这一现象并不仅局限于英国,而是一个全球问题,并且数量在不断上升。例如,在澳大利亚的新南威尔士,1999年10月至2000年9月间约有4万部移动电话被偷或被抢,比前一年增长了100%。 相似文献
6.
Fincham Frank D.; Beach Steven R. H.; Davila Joanne 《Canadian Metallurgical Quarterly》2007,21(3):542
Does forgiveness predict later conflict resolution in married couples? Twelve-month follow-up data on conflict resolution were collected from the couples studied by F. D. Fincham, S. R. Beach, and J. Davila (see record 2004-11293-007), who had provided earlier reports of forgiveness and conflict resolution. For wives, the positive dimension of forgiveness or benevolence predicted husbands' later reports of better conflict resolution controlling for initial levels of conflict resolution. This finding was independent of wives' marital satisfaction and the degree of hurt engendered by husbands' transgressions. For husbands, the only predictor of wives' reports of later conflict resolution was initial level of conflict resolution. The findings are discussed in terms of the direction of effect between forgiveness and conflict resolution and of the mechanisms that might link them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Abstract: Researchers frequently approach questions dealing with local fiscal decision‐making using economic models. These models typically base the demand for public services on a set of socioeconomic characteristics that serve as rough proxies for voter preferences. Our study focuses more directly on preference formation and explores the nature of the relationship between citizens’ attitudes about police services and their willingness to pay for them. We pay particular attention to the role of demographic traits, television media, and direct contact with service providers. We present data from a survey of Connecticut adults and use these data to test direct and indirect effects models with regression analysis. We find evidence that attitudes about police predict willingness to pay for police services, holding the demographic attributes of respondents constant. We also find that the effects of some demographic traits on demand for services are mediated by preferences, as are some types of experience and media exposure. 相似文献
8.
Five studies examined the hypotheses that when people experience positive affect, those low in self-esteem are especially likely to dampen that affect, whereas those high in self-esteem are especially likely to savor it. Undergraduate participants' memories for a positive event (Study 1) and their reported reactions to a success (Study 2) supported the dampening prediction. Results also suggest that dampening was associated with worse mood the day after a success (Study 2), that positive and negative affect regulation are distinct, that self-esteem is associated with affect regulation even when Neuroticism and Extraversion are controlled (Studies 3 and 4), and that self-esteem may be especially important for certain types of positive events and positive affect regulation (Study 5). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Stewart Abigail J.; Antonucci Toni C.; Veroff Joanne B. 《Canadian Metallurgical Quarterly》2003,58(5):405
Presents an obituary for Elizabeth Douvan (1926-2002). Douvan was a pioneer in the study of changing gender, work, and family roles; personal values; and well-being in the second half of the 20th century. Through her research, she contributed to the interdisciplinary fields of social psychology and women's studies while building and strengthening institutions that remain committed to the same mission. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
This article reviews research on the implementation of media-rating systems, parents' use and evaluation of them, and the impact of ratings on children. Although half or more of parents report using media-rating systems, understanding of various components of the systems is low, particularly for television ratings. A meta-analysis of national polls shows that parents overwhelmingly prefer that ratings specify content, rather than giving age recommendations. A second meta-analysis, of experiments testing the effects of ratings on children's interest in programs, shows that ratings indicating restricted or controversial content have a deterrent effect for children under age 8 but that, by age 11 and especially for boys, the ratings show a small enticement effect. This effect occurs for both age-based and content-based ratings. Implications for policymakers and parents are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献