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91.
贵州北盘江流域先秦时期遗存分期与相关问题   总被引:1,自引:0,他引:1  
本文通过对贵州北盘江流域先秦时期遗存的分析,依据文化面貌的差异将其分为三期,并结合周邻地区同时期材料的比对判定其年代。在此基础上,对它们所体现的葬俗、生计方式、居住形态和文化性质等方面进行探讨。  相似文献   
92.
93.
Abstract: What ethical obligations do researchers have to research informants in marginalised communities in serious distress? Our “dissemination as intervention” exercise reported research findings back to a South African rural community—using a dialogical approach which sought to strengthen participants’ confidence and ability to respond more effectively to HIV/AIDS. Nine workshops were conducted with 121 people. Workshops provided opportunities for participants to start developing critical understandings of the possibilities and limitations of their responses to HIV/AIDS, understandings which constitute a necessary (though obviously not sufficient) condition for further action. Workshops alerted participants to the valuable role played by local HIV/AIDS volunteers, facilitating reflection on how local people might better support the volunteers. These discussions served as the impetus for the establishment of a three‐year community‐led intervention to further these goals.  相似文献   
94.
This study presents the first ever lead isotope ratio data for copper ore samples (malachite and azurite) from the Sierra El Aramo (Asturias, northwestern Spain). The aim of this study was to supplement information in the existing reference database on the lead isotopic composition of Spanish ores. The Sierra El Aramo is particularly important because, while no data for the Asturian ores have been published so far, this northern province of Spain has played a significant role in terms of copper exploitation and metallurgy since the Copper Age.  相似文献   
95.
Eighty‐one samples taken from 68 glass beads found in southwestern Poland on sites of the Lusatian culture from the Hallstatt C and Hallstatt D subphases were analysed by EPMA. A subsample of 18 of these were additionally subjected to analysis by means of LA–ICP–MS in order to validate the results obtained by EPMA. Some glass was made using mineral soda and some using plant ash rich in sodium. Both high‐magnesium soda–lime glass (HMG) and low‐magnesium soda–lime glass (LMG) were identified. A large number of samples are characterized by low MgO content and medium K2O content (LMMK glass), combined with low concentrations of CaO and high Fe2O3 and Al2O3. All the LMMK glass contains numerous silica crystals and inclusions composed of a number of elements (most frequently Cu, Co, Sb, As, Ag, Ni and Fe). The LMMK glass was presumably made in Europe during the Hallstatt C.  相似文献   
96.
An integrated, multi‐analytical approach combining the high sensitivity of SR‐μXRF, the light element capability of PIXE/PIGE under a helium flux and the spatial resolution of BSEM + EDS was used to characterize chemical composition and corrosion of glass samples (first to fourth centuries ad ) from an important, but scarcely investigated, Roman region of south‐west Iberia (southern Portugal). The geochemical trends and associations of major, minor and trace elements were investigated to shed light on production techniques, the provenance of raw materials and decay mechanisms. The results, while confirming a production technique common to Roman glasses throughout the Empire—that is, a silica‐soda‐lime low‐Mg, low‐K composition, with glass additives as colouring and/or decolouring agents (Fe, Cu, Mn, Sb)—show at one site high Zr–Ti contents, suggesting a more precise dating for these glasses to the second half of the fourth century. The Ti–Fe–Zr–Nb geochemical correlations in the pristine glass indicate the presence of minerals such as ilmenite, zircon, Ti‐rich Fe oxides and columbite in the sands used as raw materials for the glass former: these minerals are typical of granitic‐type source rocks. The unusually high K content in the corrosion layers is consistent with burial conditions in K‐rich soils derived from the alteration of 2:1 clays in K‐bearing rock sequences.  相似文献   
97.
The geological sources of obsidian in the Red Sea region provide the raw material used for the production of obsidian artefacts found in prehistoric sites on both sides of the Red Sea, as far afield as Egypt, the Persian Gulf and Mesopotamia. This paper presents the chemical characterization of five obsidian geological samples and 20 prehistoric artefacts from a systematically excavated Neolithic settlement in highland Yemen. The major element concentrations were determined by SEM–EDS analysis and the trace element concentrations were analysed by the LA–ICP–MS method, an almost non‐destructive technique capable of chemically characterizing the volcanic glass. A comparison of archaeological and geological determinations allows the provenance of the obsidian used for the Neolithic artefacts to be traced to definite sources in the volcanic district of the central Yemen Plateau.  相似文献   
98.
The growth of modern nationalism can be attributed to structural causes, especially the growth of the strong bureaucratic state that penetrates society, creating cultural uniformity and national identity. But structurally based nationalism need not be very intense, or constant; even when institutionalised in periodic formal rituals, it can be routine, low in emotion – even boring. We need to explain sudden upsurges in popular nationalism, but also their persistence and fading in medium‐length periods of time. Nationalist surges are connected with geopolitical rises and falls in the power‐prestige of states: strong and expanding states absorb smaller particularistic identities into a prestigious whole; weaker and defeated states suffer delegitimation of the dominant nationality and fragment in sudden upsurges of localising nationalities. Passing from macro‐patterns to micro‐sociological mechanisms, conflict producing solidarity is a key mechanism: dramatic events focus widespread attention and assemble crowds into spontaneous ‘natural rituals’ – mass‐participation interaction rituals, as distinct from formal rituals. Evidence from public assemblies and the display of national symbols following the terrorist attacks of 11 September 2001 (9/11) shows an intense period of three months, then gradual return to normal internal divisions by around six months. Spontaneous rituals of national solidarity are produced not only by external conflict but by internal uprisings, where an emotional upsurge of national identity is used to legitimate insurgent crowds and discredit regimes. Although participants experience momentary feelings of historic shifts, conflict‐mobilised national solidarity lives in a 3–6‐month time‐bubble, and needs to institutionalise its successes rapidly to have long‐term effects.  相似文献   
99.
S. L. POTTER  M. A. CHAN 《Geofluids》2011,11(2):184-198
The Jurassic Navajo Sandstone of Grand Staircase Escalante National Monument (GSENM), Utah, exhibits a broad range of iron oxide/oxyhydroxide concretionary geometries that record a complex paragenetic history of the reservoir. The concretionary geometries are as follows: (i) common macroconcretions (>5 mm in diameter), (ii) ubiquitous microconcretions (<5 mm in diameter), (iii) localized iron oxide/oxyhydroxide‐lined northeast‐striking joints, and (iv) loopy asymmetrical mineralization and banded precipitation patterns (Liesegang bands) associated with the joints. Spheroidal concretion geometries typically indicate diffusive mass transfer, whereas asymmetrical mineralization represents advective directional flow. Liesegang bands parallel to asymmetrical mineralization denote a diffusive mass transfer component perpendicular to the principal flow direction. Careful study of concretionary geometries and their cross‐cutting relationships establishes a relative timing of precipitation and mobilization events. Macroconcretions formed post‐Laramide (<55 Ma), prior to and independent of the Miocene joints. The joints provided conduits for later oxidizing fluids that precipitated iron oxide/oxyhydroxide lining on the joint faces. Advective mass transfer overprinted the area with preferentially cemented flow lines (asymmetrical mineralization) less than 10 Ma, coincident with development of a hydraulic low to the southeast of the region (Colorado River downcutting). Certain trace elements are genetically tied to concretion formation, and evaluation of trace elements establishes precursor mineral phases. Enriched uranium concentrations in concretions (relative to the host rock) and low/undetectable sulfur concentrations in both host rock and concretions suggest that iron oxyhydroxide was a primary precipitate rather than a reduced iron mineral (i.e., pyrite or siderite) that later oxidized. Enrichment of Ni and As in concretions functions as fingerprints for diagenetic concretion formation when determining genesis of ambiguous iron oxide/oxyhydroxide spherules such as the remotely sensed ‘blueberries’ on Mars. Similarities between Mars and Utah spherules such as geometry, in situ spacing and volumetric density suggest that Mars spherules precipitated via a geochemically self‐organized nucleation pattern in diffusive chemical reaction fronts.  相似文献   
100.
Obsidian is an effective material for the study of prehistoric raw material use and exchange, due to the high degree of homogeneity and redundancy of obsidian materials and manufactured objects in the archaeological record. The destructive nature of many analytical techniques often impedes compositional research because of the damage that may occur to priceless archaeological artefacts. The combination of time‐of‐flight (TOF) ICP–MS with a laser ablation sample introduction system provides a highly efficient means of chemically characterizing obsidian. This study shows that sample size limit capabilities of TOF–ICP–MS analysis of obsidian can reach less than 100 μm. Sampling and analysis of microartefacts enables researchers to overcome problems of sampling bias with very little damage to the valuable existing materials within the archaeological record and expands the potential for chemical compositional analyses in archaeology.  相似文献   
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