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71.
72.
Low temperature (90–190 °C) hydrothermal experiments have been conducted on seven obsidians where composition of the glass varies significantly in the concentration of structural water within the unhydrated bulk material. Infrared transmission spectroscopy was used to track the diffusion of molecular water into the glass surface as a function of time and temperature. Long-term (60–360 days) hydration sequences at 90 °C show a t0.6 time dependence for the mass uptake of molecular water that forms the hydration layer. The structural water concentration of the unhydrated bulk obsidian is highly correlated with the pre-exponential and activation energy and may be used to estimate the Arrhenius constants. In addition, secondary ion mass spectrometry (SIMS) hydrogen profiling of Napa Glass Mountain obsidian hydrated at 90 °C reveals that the early stages of diffusion exhibit a dynamic behavior that includes a fluctuating hydrogen concentration and a changing diffusion coefficient that slows with time. 相似文献
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74.
ABSTRACT This research analyzes manufacturing growth and decline across metropolitan and nonmetropolitan regions during the 1972–2002 period. We decompose real value added growth across local labor market areas in the lower 48 U.S. states into contributions from labor, capital, and total factor productivity. We then estimate a model describing the long‐run growth of labor, capital, and productivity and find that increased productivity increases the growth of labor and capital, as well as a positive correlation between labor and capital stock growth. We also find evidence that human capital investment and agglomeration economies encourage productivity growth, while unionization discourages it. 相似文献
75.
Kerry F. Thompson 《Archaeologies》2011,7(3):502-517
There are several major considerations for the Navajo Nation that foreground questions of inclusion in public archaeology.
The traditional Diné view of archaeological remains requires an evaluation of the public archaeologist’s notion of inclusion
of Diné communities in archaeological research. Archaeological work on the Navajo Nation is also often a source of frustration
for Diné communities because a shortage of human and monetary resources slows the pace of legislated archaeological compliance,
in turn, slowing down vital housing and road infrastructural development. Finally, for Diné archaeologists, the structure
of project development is not necessarily conducive to the creation of an intellectual foundation for Diné archaeology or
community engagement in archaeological research. 相似文献
76.
Ricardo Fernandes Geert Geeven Steven Soetens Vera Klontza-Jaklova 《Journal of archaeological science》2011
This paper introduces GIS-based statistical methods for the study of settlement patterning in an archaeological context. The main aspect is an improvement over suboptimal stepwise statistical model selection procedures, with the introduction of a Deletion/Substitution/Addition (DSA) algorithm, a systematic model selection algorithm that provides an optimal model choice. The paper also introduces the combined use of Receiving Operator Characteristic (ROC) curves, and variable ranking as key tools aimed at an understanding of settlement patterning causation. An illustrative case study is provided whereby both a purely environmental and a mixed environmental/historical model (based on settlement hierarchy considerations) are investigated. 相似文献
77.
Steven R. Holloway 《Social & Cultural Geography》2013,14(2):197-208
Traditional research in urban geography concerned with issues of 'race' has focused on a series of substantively important issues, yet with conceptual foundation inadequate to the task. Specifically, this body of work has employed outdated and theoretically limited conceptions of identity without sufficient consideration to the importance of historical and geographic contingency. I argue in this essay that topics of traditional concern to urban geography gain new relevance and importance when they are reconsidered and reworked from a social constructivist perspective that takes seriously the importance of identity and contingency. I illustrate my argument with discussions of two aspects of my current research agenda. First, I discuss how research on urban residential segregation gains considerably from a more sensitive encounter with multifaceted notions of identity that explicitly address geographic contingency. Second, I review recent empirical research on US mortgage-lending markets that demonstrates the geographic and class contingency of discrimination. The paper ends with a call for research that employs multiple methodologies. 相似文献
78.
J. H. Bird F. H. Stewart A. F. Williams J. D. Thompson R. M. Frothero 《Scottish Geographical Journal》2013,129(1):52-53
EUROPE The Soils around Jedburgh and Morebattle. By John W. Muir. 9 ¾×6 ¾. Pp. 878. 2 maps. 20 tables. 11 diagrams. 32 plates. 8 colour plates. Edinburgh : H.M.S.O., 1956. 30s. The British Moorlands : A problem in land utilisation. By John Fraser Hart. 8 ½×5 ½. Pp. viii+98. 25 figures. University of Georgia Monograph, No. 2. Athens (U.S.A.) : Georgia University Press, 1955. $2.00. European Refugees : A Study in Forced Population Movement. By Malcolm J. Proudfoot. 5 ½×8 ½. Pp. vi+542. 49 tables. 2 maps. London: Faber &; Faber Ltd, 1957. 52s 6d. East Norway and its Frontiers. By Frank Noel Stagg. 8 ¾×5 ¾. Pp.285. 15 plates. 6 maps. London : Allen and Unwin Ltd, 1956. 18s. La Yougoslavie : Aperçu Géographique. By B. Z. Milojevic. Translated by Mila Dordlvic. 9 ¼×6 ½. Pp. xi+89. I folded end map and numerous figures and plates. Beograd : La Commission pour les relations culturelles avec l'étranger, 1956. ASIA The Pakistani Way of Life. By I. H. Qureshi. 8 ¾×5 ¾. Pp. xi+81. 23 plates. London : William Heinemann Ltd, 1955. 12s 6d. Indian Climatology. By S. B. Chattergee. 9 ½×6 ¼. Pp. 417. 36 tables. 80 diagrams. Calcutta : Commercial Printers, 1955. 20s. Asia : Sketch Map and Exercise Books for upper forms. Book VII. By Thomas Pickles. 7 ¼×9 ¾. Pp.48. London : John Murray Ltd, 1956. 3s. AMERICA The Industrial Structure of American Cities : A geographic study of urban economy in the United States. By Gunnar Alexandersson. 10×7 ½. Pp. 134. 40 figs. 13 maps. London : Allen and Unwin Ltd, 1956. 40s. CARTOGRAPHY Topographical Maps and Photographic Interpretation. By P. T. Silley. 9 ½×6 ½. Pp. vii+76. 8 maps with 8 plates. 3 plates. 53 figs. London: George Philip and Son Ltd, 1955. 10s 6d. Map and Photo Reading. By T. W. Birch. 10×7 ½. Pp.64. 24 maps and photos. London: Edward Arnold and Co., 1956. 16s. Mapping the World. By Erwin Raisz. 6 ½×9 ½. Pp. 112. 72 figs and 7 plates. London : Abelard‐Schuman, 1956. 12s 6d. GEOLOGY AND GEOMORPHOLOGY Introduction to Physical Geology. By Chester R. Longwell and R. Foster Flint. 9 ¼×6 ½. Pp.vii+432. Plates and figs. 2 end paper maps. London: Chapman and Hall Ltd, 1955. 40s. Geology and Ourselves. By F. H. Edmunds. 9 ¼×6 ½. Pp. 256. 12 plates. 15 figs. London : Hutchison's Scientific and Technical Publications, 1955. 21s. Der Bodenfrost als Morphologischer Faktor. By Josef Schmid. 9 ½×7 ½. Pp. viii+144. 27 figs. 5 plates. Heidelberg : Dr Alfred Huthig Verlag, 1955. Vocabulaire Franco‐anglo‐allemande de Geomorphologie. By Henri Baulig. 9 ½×6 ¼. Pp. xxv+230. Publications de la Faculte des lettres de l'Université de Strasbourg. Fasc. 130. Paris: Société d'edition: Les Belles Lettres, 1956. 1,200 fr. ECONOMIC GEOGRAPHY World Economic Geography. By Earl B. Shaw. 8 ¾×6 ½. Pp. vii+582. Maps, diagrams and plates. New York : John Wiley and Sons Inc. London : Chapman and Hall Ltd, 1955. 52s. Chisholm's Handbook of Commercial Geography. Re‐written by L. Dudley Stamp and S. Carter Gilmour. 15th Edition. 8 ¾×6. Pp. viii+915. 30 maps and diagrams. London : Longmans, Green and Co. Ltd, 1956. 70s. La Pêche maritime el le Pêcheur en Mer. By Auguste Dupouy. 6 ½×4 ¼. Pp. 216. [Collection Armand Colin, No. 300.] Paris : Librairie Armand Colin, 1955. 250 fr. GENERAL A Concise Glossary of Geographical Terms. By J. C. Swayne. 6 ¼×4. Pp. 164. London : George Philip and Son Ltd, 1956. 6s 6d. Worlds Beyond the Horizon. By Joachim G. Leithauser. Transl. by Hugh Merrick. 9 ½×6. Pp. 371. 46 plates+frontispiece. London : Allen and Unwin Ltd, 1956. 40s. A Guide to Earth History. By Richard Carrington. 8 ½×5 ½. Pp. xvi+240. 44 figs. 16 plates, including coloured frontispiece, by Maurice Wilson. London : Chatto and Windus Ltd, 1956. 21s. Puzzle of the Past. By Ronald Jessup. 12 ¾×9 ¾. Pp.68. Illustrations (colour/black and white). London : Rathbone Books, 1956. 15s. ATLASES AND MAPS The Oxford Home Atlas of the World. By Geoffrey Cumberlege. 10×7 ¾. Pp. viii+104+xxxi. London: Oxford University Press, 1955. 15s. Map of Roman Britain : 16 miles to one inch. Third Edition. Text 11×8 ¼. Pp.43. 4 maps+Map of Roman Britain. Chessington : Ordnance Survey, 1956. 7s 6d. Penguin Atlas. Edited by J. S. Keats. 8×5 ¾. Pp. xv+156. 80 colour maps. Harmondsworth : Penguin Books Ltd, 1956. 10s. Oxford Regional Economic Atlas of the U.S.S.R. and Eastern Europe. Oxford : Clarendon Press. London : Cumberlege, 1956. 42.s. 相似文献
79.
80.
Gang Meng G. Brent Hall Mary E. Thompson Patrick Seliske 《The Canadian geographer》2013,57(2):154-172
This study assesses the overall spatial variations and neighbourhood‐level “hot spots” of low birth weight and preterm birth incidence within three public health units in Ontario, Canada. The analysis uses a stepwise approach of intra‐class correlation analysis, a spatial scan statistic, and multilevel spatial modeling. Results show that neighbourhood level variation accounts for only 2–3 percent of the total variation of adverse birth outcomes in the study area. However, strong spatial autocorrelation is observed at the neighbourhood level, and spatial clusters of relatively high adverse birth outcome rates exist in areas that are associated with environmental risks, including pollution sources and proximity to highways. Thus, although estimated neighbourhood impacts on adverse birth outcomes are small compared with those of individual‐level risks, local high potential environmental risk areas are identifiable. Environmental surveillance and spatial statistical analysis should be conducted regularly by local health authorities to identify and monitor the impact of environmental changes on health in general and on birth outcomes in particular. Specific community‐oriented health interventions may be required to reduce observed local health impacts. 相似文献