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61.
Scott M. Fitzpatrick Hiroto Takamiya Hector Neff William R. Dickinson 《Geoarchaeology》2006,21(8):803-822
In Okinawa, locally produced pottery dates back to the Initial Jomon period (˜6500 14C yr B.P.). Later in time, especially during the Early Yayoi‐Heian period (˜300 B.C.–A.D. 300), ceramic assemblages appear to contain mainland (Japan) Yayoi pottery. A greater number of these sherds present in Okinawa over time coincide with an increasing amount of interaction with mainland Japan, as evidenced by other exchange items. In this preliminary study, the authors analyzed sherds from several Early Yayoi‐Heian period deposits from sites in Okinawa using thin‐section petrography and laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS). The objective was to examine the applicability of these techniques for Okinawan ceramic provenance studies, assess intra‐ and intersite variation in mineralogical and chemical composition, and determine whether some sites exhibited a higher frequency of pottery from one locale versus another that might suggest the importation of pottery from mainland Japan. Results are equivocal, suggesting that the region's geological complexity may inhibit successful provenance study of ceramics using these and possibly other compositional techniques. © 2006 Wiley Periodicals, Inc. 相似文献
62.
Absolute spectrophotometry of the coma of Comet Kohoutek 1973f is discussed for the nights of January 24 and 26, 1974. Specific intensities are measured for spectral features and a continuum band in the wavelength region λλ3460–6062Å. The (0, 0) band of the Δν = 0 sequence of the violet system of the cyanogen molecule is analyzed and column densities of 1.7 × 1015m?2 and 3.4 × 1014m?2 are found for January 24 and 26, 1974, respectively. The analysis of the bands of C2 will be reported in a second paper of this series. 相似文献
63.
Paul A. Scowen Mario R. Perez Susan G. Neff Dominic J. Benford 《Experimental Astronomy》2014,37(1):11-35
Following several recommendations presented by the Astrophysics Decadal Survey 2010 centered around the need to define “a future ultraviolet-optical space capability”, on 2012 May 25, NASA issued a Request for Information (RFI) seeking persuasive ultraviolet (UV) and visible wavelength astrophysics science investigations. The goal was to develop a cohesive and compelling set of science objectives that motivate and support the development of the next generation of ultraviolet/visible space astrophysics missions. Responses were due on 10 August 2012 when 34 submissions were received addressing a number of potential science drivers. A UV/visible Mission RFI Workshop was held on 2012 September 20 where each of these submissions was summarized and discussed in the context of each other. We present a scientific analysis of these submissions and presentations and the pursuant measurement capability needs, which could influence ultraviolet/visible technology development plans for the rest of this decade. We also describe the process and requirements leading to the inception of this community RFI, subsequent workshop and the expected evolution of these ideas and concepts for the remainder of this decade. 相似文献
64.
Differentiating clay resources in a uniform limestone plain, such as occurs in northern Belize, offers special challenges for the archaeologist. Combining data from soil mapping with petrographic and neutron activation analysis provides a mechanism for distinguishing possible resource areas. This study employed each of these differing avenues of analysis to determine possible clay resource areas used during the Maya Formative in northern Belize Central America. The results indicate that clay usage changed significantly from the Middle Formative period to the end of Late Formative period. These changes suggest a move to increased localized production and resource exploitation by the end of the period. © 2000 John Wiley & Sons, Inc. 相似文献