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21.
动物标本的有害物主要产生于标本制作过程、保养方式和所处环境。为了解有害物残留情况,对广东省博物馆的动物标本抽样进行了能量色散X射线荧光光谱分析法(ED-XRF)和电感耦合等离子体发射光谱法(ICP-OES)实验分析。研究发现,馆藏动物标本羽毛和毛均有不同含量的硫(S)、钙(Ca)、砷(As)、氯(Cl)、钾(K)、铝(Al)、铁(Fe)、硅(Si)、锌(Zn)等元素;哺乳动物和大型猛禽标本的铁、锌等微量元素质量比高于其他实验物种;自然状态下,砷元素长期附着标本的表面和内部,毒性可影响接触者,不利于环保。建议剥制动物标本过程中避免使用砷化物。  相似文献   
22.
唐代出现了大量文人所写的应用性传记。其中,他传性托传基本上体现史传的“有益于世”的精神,但和史传的具体写作目的截然不同,它不用拘于史传的种种体式,具有多种多样的表现形式。所以,他传性托传的突破传统史传体式,使得传统的“传”由单纯记述历史的散文发展成为极富文学艺术性的散文,从而开创了中国传记文学的新天地。  相似文献   
23.
康熙时期的养心殿   总被引:2,自引:0,他引:2  
养心殿作为宫内的一处重要建筑,在康熙时期的情况一直不甚清楚。本文通过零星的记载,尤其是当时西方传教士的著作,对康熙时期养心殿的建筑格局、内部陈设、使用情况等进行了考证,认为与雍正以后的状况有很大差异,其功用是多方面的,从而对养心殿历史沿革的认识更为全面。  相似文献   
24.
后过程主义考古学的形成——读伊恩·哈德《解读过去》   总被引:1,自引:0,他引:1  
张海 《东南文化》2003,(11):13-16
考古学的进步是以丧失其纯洁性为代价的。  相似文献   
25.
One hundred and twenty-eight colourless glass tablewares from settlement contexts throughout the British Isles, dating from the mid-3rd to 4th century AD, were analysed by ICP-AES spectrometry. Three distinct compositional groups were identified based upon the use of different decolourisers and primary raw materials, with possible sub-groups within these. These compositions have distinct, but overlapping chronological ranges, suggesting colourless glass production in at least three, possibly more, centres in the late Roman period. The compositional analysis highlights the high degree to which recycling of glass was taking place during this late period. The chronological distribution of some of these compositions is more restricted within the British assemblages than is observed in other published assemblages from Western Europe. This distinction may indicate different supply patterns of glass to the Western provinces.  相似文献   
26.
Archaeological wood, as most of natural materials, is slowly decomposing on the archaeological site due to various biological factors. Rapid and accurate estimation of the degradation level is extremely important for optimal restoration and conservation. The goal of this research was to verify the effectiveness of Fourier transform near infrared (FT-NIR) spectroscopy for archaeometry. The important advantage of the NIR spectroscopy is its accuracy, simplicity and ability to perform very high number of tests without needs of any destruction to the workpiece. Five oak pieces of the archaeological wood collected from waterlogged sites in Poland have been used. Cellulose and lignin contents, as well as crystallinity and the degree of polymerization were measured with standard reference methods and compared to the contemporary wood. The near infrared spectra represent all the physical/chemical changes of the wood due to waterlogging. This technique was successfully validated in rapid estimation of the cellulose and lignin contents. The method explored in this research might be a novel tool assisting experts in evaluation of the degradation state of archaeological and historical wooden materials.  相似文献   
27.
为研究出土墓葬青铜器铸造地,利用X射线荧光光谱法对湖北襄樊的余岗、沈岗、团山、陈坡四处墓地出土的部分青铜器泥芯、陶片进行测试分析,试验结果与山西侯马、武汉盘龙城遗址进行比较分析。对比研究显示,襄樊地区泥芯与当地墓土、陶片在常量元素上具有高度一致性,而与黄河流域的侯马和长江中下游的盘龙城有明显区别,说明襄樊地区这部分铜器应为本地铸造,暗示江汉流域存在自己特有文化。本项研究工作首次尝试利用同墓葬陶器化学成分探索青铜器铸造地,是泥芯研究青铜器铸造地的重要补充,泥芯和陶器相互配合,为青铜器铸造地研究提供了一种新思路。  相似文献   
28.
A dated (1773) openwork basket labelled “PHILADELFIA” attributed to the Bonnin and Morris factory has a lead-bearing, silicious–aluminous–calcic (S-A-C) composition that contrasts with the phosphatic (bone ash) porcelains known to have previously been made during the mid-1760s to early 1770s in what is now the United States. The basket was underfired and so contains relics of a flint (Pb) glass flux, but kiln temperatures were nonetheless sufficient for subsolidus pseudowollastonite and anorthite to have been resorbed, implying that the duration of firing (soaking) near peak kiln temperatures was insufficient to ensure thorough vitrification. During cooling, liquidus pseudowollastonite and silica polymorphs (but not anorthite) formed, showing that the melt was confined to the tridymite–pseudowollastonite cotectic above the Trd–Wol–An eutectic (1170 °C) in the SiO2–Al2O3–CaO system. Rapid cooling is also indicated by quenched silica polymorphs in the relict glass particles. Although Bonnin and Morris employed some former Bow (London, c. 1743–74) workers, the S-A-C wares initially produced by this factory are compositionally distinct from the 1773 basket, which in this regard more closely resembles the body and glaze of a reputed Chelsea triangle-period (London, c. 1745–49) vessel. Regardless of how they obtained this technology, it is ironic that Bonnin and Morris chose to abandon phosphatic pastes in favour of what in Britain had become an obsolete formula.  相似文献   
29.
The early medieval period marks an important turning point in the history of glassmaking, since it comprises the transition period between the mineral-based silica-soda-lime glass of the Roman tradition and the plant ash-based glass. With the aim of expanding the knowledge on the glass recipes and technologies of this period, 37 glass samples were analyzed, originating from the archaeological excavations of San Genesio (Tuscany) and dated from the fourth to the eleventh century. The major and minor element concentrations were measured with SEM-EDX, while the trace elements were quantified with LA-ICP-MS. The results were compared with published compositions of glass samples of similar age in order to highlight differences and similarities. The results offer a very interesting view on the glass circulation in the religious/residential/manufacturing center of San Genesio in the early medieval period. Most of the glass has a typical late-Roman composition, but some glass fragments are identified as soda ash glass. These are among the earliest medieval ash-fluxed glasses ever found in the Italian peninsula.  相似文献   
30.
Mineral deposits in the Cupp‐Coutunn/Promeszutochnaya cave system (Turkmenia, central Asia) record a phase of hydrothermal activity within a pre‐existing karstic groundwater conduit system. Hydrothermal fluids entered the caves through fault zones and deposited sulphate, sulphide and carbonate minerals under phreatic conditions. Locally, intense alteration of limestone wall rocks also occurred at this stage. Elsewhere in the region, similar faults contain economic quantities of galena and elemental sulphur mineralization. Comparisons between the Pb and S isotope compositions of minerals found in cave and ore deposits confirm the link between economic mineralization and hydrothermal activity at Cupp‐Coutunn. The predominance of sulphate mineralization in Cupp‐Coutunn implies that the fluids were more oxidized in the higher permeability zone associated with the karst aquifer. A slight increase in the δ34S of sulphate minerals and a corresponding δ34S decrease in sulphides suggest that partial isotopic equilibration occurred during oxidation. Carbonate minerals indicate that the hydrothermal fluid was enriched in 18O (δ18OSMOW ~ + 10‰) relative to meteoric groundwater and seawater. Estimated values for δ13CDIC (δ13CPDB ~ ? 13‰) are consistent with compositions expected for dissolved inorganic carbon (DIC) derived from the products of thermal decomposition of organic matter and dissolution of marine carbonate. Values derived for δ13CDIC and δ18Owater indicate that the hydrothermal fluid was of basinal brine origin, generated by extensive water–rock interaction. Following the hydrothermal phase, speleothemic minerals were precipitated under vadose conditions. Speleothemic sulphates show a bimodal sulphur isotope distribution. One group has compositions similar to the hydrothermal sulphates, whilst the second group is characterized by higher δ34S values. This latter group may either record the effects of microbial sulphate reduction, or reflect the introduction of sulphate‐rich groundwater generated by the dissolution of overlying evaporites. Oxygen isotope compositions show that calcite speleothems were precipitated from nonthermal groundwater of meteoric origin. Carbonate speleothems are relatively enriched in 13C compared to most cave deposits, but can be explained by normal speleothem‐forming processes under thin, arid‐zone soils dominated by C4 vegetation. However, the presence of sulphate speleothems, with isotopic compositions indicative of the oxidation of hydrothermal sulphide, implies that CO2 derived by reaction of limestone with sulphuric acid (‘condensation corrosion’) contributed to the formation of 13C‐enriched speleothem deposits.  相似文献   
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