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JANICE MONK 《Geographical review》2006,96(2):259-277
ABSTRACT. In 1973 Wilbur Zelinsky lamented and documented the low representation of women in American academic geography. His attention reflected the climate of the times—the challenges of the women's movement, affirmative action, and feminist activism in the professions. Drawing on archives and personal narratives, this article addresses the paradoxes and politics of women's place in American academic geography in the 1970s. As increasing numbers developed new aspirations for graduate education and professional work, stereotyping, discrimination, the lack of mentoring, and the challenges of a job market whose peak had passed presented difficulties. Yet persistence, resistance, and feminist political activism worked to advance women's professional standing and visibility, especially at the national level within the Association of American Geographers and in the development of new research and teaching on the geography of women. 相似文献
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JANICE L. BISHOP CARL M. PIETERS TAKAHIRO HIROI JOHN F. MUSTARD 《Meteoritics & planetary science》1998,33(4):699-707
Abstract— Spectroscopic measurement and analysis of Martian meteorites provide important information about the mineralogy of Mars, as well as necessary ground-truths for deconvolving remote sensing spectra of the Martian surface rocks. The spectroscopic properties of particulate ALH 84001 from 0.3 to 25 μm correctly identify low-Ca pyroxene as the dominant mineralogy. Absorption bands due to electronic transitions of ferrous iron are observed at 0.94 and 1.97 μm that are typical for low-Ca pyroxene. A strong, broad water band is observed near 3 μm that is characteristic of the water band typically associated with pyroxenes. Weaker features near 4.8, 5.2 and 6.2 μm are characteristic of particulate low-Ca pyroxene and can be distinguished readily from the features due to high-Ca pyroxene and other silicate minerals. The reflectance minimum occurs near 8.6 μm for the ALH 84001 powder, which is more consistent with high-Ca pyroxene and augite than low-Ca pyroxene. The dominant mid-infrared (IR) spectral features for the ALH 84001 powder are observed near 9 and 19.5 μm; however, there are multiple features in this region. These mid-IR features are generally characteristic of low-Ca pyroxene but cannot be explained by low-Ca pyroxene alone. Spectral features from 2.5–5 μm are typically associated with water, organics and carbonates and have been studied in spectra of the ALH 84001, split 92 powder and ALH 84001, splits 92 and 271 chip surfaces. Weak features have been identified near 3.5 and 4 μm that are assigned to organic material and carbonates. Another feature is observed at 4.27 μm in many surface spots and in the powder but has not yet been uniquely identified. Spectroscopic identification of minor organic and carbonate components in this probable piece of Mars suggests that detection of small amounts of organics and carbonates in the Martian surface regolith would also be possible using visible-infrared hyperspectral analyses. Laboratory spectroscopic analysis of Martian meteorites provides a unique opportunity to identify the spectral features of minerals and other components while they are embedded in their natural medium. 相似文献
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JANICE MONK 《Geographical review》2003,93(2):237-257
ABSTRACT. For much of the twentieth century, women in the United States found it difficult to obtain university positions in geography. Opportunities existed in other types of institutions, however, including the American Geographical Society (ags ). This article addresses ways in which the Society's mission intersected with its historical context from 1895 to 1970 to create niches for women in editorial and library work. It explores the women's origins, their perspectives and experiences with the ags , and the significance of their contributions to the discipline. It suggests the potential of a gendered social approach for enriching understanding of the histories of geographical institutions. 相似文献
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DAVID J. MONK 《Geophysical Prospecting》1993,41(6):725-736
A method for improving the attenuation of water-layer multiple energy is suggested. The improvement is achieved using wave-equation extrapolation to generate an initial model of the multiple energy, and then constraining the way in which this model is modified to fit the observed multiple energy. Reconciling the initial multiple model with the input data is a critical part of this process and several techniques have been suggested previously by other authors. The approach used here is to fit the time, amplitude and phase of the wavelets by adapting the initial model trace using a weighted sum of four traces which can each be derived from the initial multiple model trace. Results on real data suggest that attenuation of primary energy is minimized using this technique, without diminishing the level of multiple attenuation. 相似文献
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JANICE L. BISHOP JOHN F. MUSTARD CARL M. PIETERS TAKAHIRO HIROI 《Meteoritics & planetary science》1998,33(4):693-698
Abstract— Reflectance spectra of splits 92 and 271 from the Martian meteorite Allan Hills (ALH) 84001 are presented and analyzed in this paper. Although the visible and infrared spectra of both chips show that the dominant mineralogy is low-Ca pyroxene, the focus here is on identification of the minor constituents. Infrared spectra measured at multiple spots along the surface of chips 92 and 271 show subtle spectroscopic variations due to changes in the low-Ca pyroxene texture and composition and to the presence of secondary minerals. Absorption bands observed near 0.93 and 1.95 μm are characteristic of low-Ca pyroxene. Strong mid-infrared reststrahlen bands are observed near 9 and 19.5 μm in all surface spectra, and additional bands near 7, 10.5, 11.4, 17.8, 20.5 and 23 μm are variable depending on the low-Ca pyroxene texture and the presence of secondary minerals. Selected spectra exhibit carbonate features near 4, 6.4–7.1 and 11.3 μm. Detailed analysis of these carbonate features indicates the presence of Mg-Fe carbonate, which is consistent with petrographic studies. Many of these spectra with strong carbonate features exhibit a magnetite feature near 17.9 μm and a shoulder near 20.5 μm that cannot be uniquely ascribed to one mineral. Spectroscopic identification of the minor carbonate and magnetite minerals in this probable piece of Mars indicates that detection of small amounts of these minerals of possible biological significance will be possible using infrared hyperspectral analyses of the Martian surface. Also of importance for remote sensing on Mars is the result that Mg, Fe and Mg-Fe carbonates in a low-Ca pyroxene matrix should be distinguishable from one another in the spectral region measured by the thermal emmitance spectrometer (TES). 相似文献
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