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51.
根据墓葬形制和随葬品特征,可以推定扬州甘泉山二号墓主是东汉晚期而不是东汉早期的广陵王。文献记载也表明,终东汉之世,广陵国的王国地位始终保持,附近发现的"广陵王玺"金印为东汉晚期或使用至东汉晚期的可能性都存在。  相似文献   
52.
The development of alternative solutions for precast concrete buildings based on jointed ductile connections has introduced innovative concepts in the design of lateral-load resisting frame and wall systems. Particularly efficient is the hybrid system, where precast elements are connected via post-tensioning techniques and self-centring and energy dissipating properties are adequately combined to achieve the target maximum displacement with negligible residual displacements. In this contribution, the concept of hybrid system is extended to bridges as a viable and efficient solution for an improved seismic performance when compared with monolithic counterparts. Critical discussion on the cyclic behaviour of hybrid systems, highlighting the most significant parameters governing the response, is carried out.

The concept of a flexible seismic design (displacement-based) of hybrid bridge piers and systems is proposed and its reliability confirmed by quasi-static cyclic (push-pull) and nonlinear time-history analyses based on lumped plasticity numerical models.  相似文献   
53.
Strong ground motion close to a fault can be expected to be very large, so its estimation is essential for human safetv. Although a few strong-motion data exist for the west Eurasian region, we proposed in a previous work [Berge-Thierry et al., 2003] an attenuation relation for spectral acceleration using strong-motion data recorded in west Eurasia (mainly in Europe) and some in the western United States: this relationship was derived for the French Safety Rule, which is applied for seismic hazard assessment at nuclear power plants. In this study, we propose a constraining of the amplitude saturation term related to the proximity of the fault, and an adding of an amplitude saturation term in the regression model. We add, to the data-set previously used to derive the west Eurasian attenuation relationship strong-motions recorded during recent large earth-quakes: the 1995 Hyogo-ken Nanbu (Kobe) event in Japan and the 1999 Kocaeli (Izmit) event in Turkey. The regression analysis, adopted from Fukushima and Tanaka [1990], is non-linear, so an iterative procedure is applied. The determined regression coefficients lead to a prediction of a peak ground acceleration of about 0.7 g for soil site conditions at a fault distance of 0.5 km. The Q coefficient deduced, from the distance coefficient is in agreement with scattering Q models. The introduction of the saturation term leads to significantly lower predictions of average spectral accelerations at short distances as compared with using the Berge-Thierry et al. [2003] empirical model.  相似文献   
54.
Three small stone axes were collected by the joint Qatari‐German South Qatar Survey Project (SQSP) at two places close to the eastern and western coast of Qatar in autumn 2012. Associated with settlement remains, flint artefacts and pieces of ?Ubaid pottery, the implements have been dated to the fifth millennium BCE. Non‐destructive μ‐XRD2 and μ‐XRF analyses could, for the first time, prove the use of hematite as the raw material for the manufacture of these tools in Arabia. The absence of major hematite sources in the region and the special characteristics of hematite — a unique metallic shine of polished pieces and the blood‐red colour that appears during the manufacturing process — suggest the highly symbolic character of these objects.  相似文献   
55.
Understanding the pattern of hominin dispersal is a fundamental component of Palaeolithic archaeology and palaeoanthropology. A widely held assumption is that bifacial handaxe (i.e. Acheulean or ‘Mode 2’) technologies evolved in Africa and dispersed into northern and western Eurasia via subsequent hominin migrations. To date, however, few formal tests of this hypothesis have been presented. Here, we use a combination of morphometrics, cultural transmission theory, and a dispersal model drawn from population genetics in order to test this hypothesis. The iterative founder effect (repeated bottlenecking) model is assumed to be supported if a significant inverse relationship is found between geographic distance from source along an estimated dispersal route and within-assemblage variance. The results of our analyses support the hypothesis that Acheulean technologies evolved in Africa and dispersed with migrating hominin populations into northern and western Eurasia under the assumptions of this iterative founder effect model. Based on our results we suggest that the occurrence of certain Mode 1 technologies such as those east of the Movius Line, and some assemblages assigned to the Clactonian of Britain, plausibly represent instances where effective population sizes in colonising populations dropped below levels where Mode 2 technologies could be maintained.  相似文献   
56.
Qâni’, the main seaport for the export of goods from South Arabia, was founded by the Hadramawt kingdom in the first century BC. A geomorphological survey and a general surface reconnaissance of Qâni’ have revealed a new image of the site. Originally a royal entrepôt in a fortress on an ancient island, separated from the mainland by a silted channel lined with a mangrove forest, Qâni’ gradually grew and spread around the beach fronting the mooring place of the trade ships that arrived by sea. Sacred spaces, cemeteries, dwellings and trade quarters appear to be well‐defined areas forming a real town within the limits imposed by the surrounding sea.  相似文献   
57.
为了检测保存液pH值和Ca2 浓度对古尸骨组织脱钙的影响,本实验于2002年检测了古尸保存液的pH值和微量元素含量,然后分两步调整了马王堆古尸保存液的pH值和Ca2 浓度,并分别于2004年、2006年进行了相同检测。结果发现适当上调保存液的pH值和Ca2 浓度能明显延缓古尸保存液中Ca2 浓度的增加:而保持适当的pH值、适当降低Ca2 浓度明显加速了古尸保存液中Ca2 浓度的增加。这些表明保存液pH值和Ca2 浓度的适当提高有利于防止古尸骨组织的脱钙。  相似文献   
58.
A geochemical study was carried out on the CO2‐rich water occurring in granite areas of Chungcheong Province, Korea. In this area, very dilute and acidic CO2‐rich waters [62–242 mg l?1 in total dissolved solid (TDS), 4.0–5.3 in pH; group I) occur together with normal CO2‐rich waters (317–988 mg l?1 in TDS, 5.5–6.0 in pH; group II). The concentration levels and ages of group I water are similar to those of recently recharged and low‐mineralized groundwater (group III). Calculation of reaction pathways suggests that group I waters are produced by direct influx of CO2 gas into group III type waters. When the groundwater is injected with CO2, it develops the capacity to accept dissolved solids and it can evolve into water with very high solute concentrations. Whether the water is open or closed to the CO2 gases becomes less important in controlling the reaction pathway of the CO2‐rich groundwater when the initial pco 2 is high. Our data show that most of the solutes are dissolved in the CO2‐rich groundwater at pH > 5 where the weathering rates of silicates are very slow or independent of pH. Thus, groundwater age is likely more important in developing high solute concentrations in the CO2‐rich groundwaters than accelerated weathering kinetics because of acidic pH caused by high pco 2.  相似文献   
59.
A subterranean, stone‐built, sediment‐filled culvert discovered during excavations at the Agora (Athens, Greece) was dated to the Roman period on the basis of its characteristic construction and associated finds, including coins. The location of the culvert relative to other adjacent watercourses and an ancient river bed suggested that the structure was a sewer. This was confirmed through a multi‐molecular biomarker approach based on analysis of the bile acids associated with sediment filling the sewer, using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The acid fraction contained predominantly deoxycholic and lithocholic acids, while the neutral steroid fraction comprised a complex mixture of Δ5 sterol and 5β‐ and 5α‐stanols, dominated by coprostanol, suggesting the presence of faecal matter of predominantly human origin. The concentrations of neutral and acidic faecal biomarkers were observed to vary in tandem, with the highest concentrations being found in the sediment at the base of the fill in the culvert. A reduction in concentration occurred with decreasing depth of the fill, with concentrations in the uppermost samples being little different from control samples of sediment taken beyond the confines of the culvert. The enhanced concentration of bile acids relative to 5β‐stanols compared with fresh human faeces must reflect the enhanced diagenetic stability of the former, thereby making bile acids the possibly preferred biomarker for this type of study. The quantitative data obtained suggest that the culvert fell rapidly out of use, possibly coinciding with the Slavic incursion in AD 582–3.  相似文献   
60.
The use of ding-tripod in Chu tombs was well established in the Warring States period and in most cases, it was strictly implemented. However, exceptions do exist. For example, in tomb of Marquis Yi of the Zeng state, archaeologists found two qiao-ding, which consists of two ding- tripods, one with a fitted lid and the other with a hooped lid. In the tomb No. 1 at Jiuliandun, a ding-tripod with a hooped lid was intentionally used and served as xu-ding. This paper attempts to understand burial rituals of the Chu state during the Warring State period by examining the tomb inventories (catalogues of funerary goods in the tombs) unearthed from the tomb No. 2 at Baoshan. It proposes that the use of ding-tripod in tombs was often adjusted according to the burial rituals.  相似文献   
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