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1.
This paper is the outcome of a lecture held at the Institute of Archaeology, University College London. It provides a summary in English of the archaeozoological research work which has been carried out in Central Europe during the last 30 years, with special reference to material from medieval times. It is shown that a thorough zoological analysis of bones from excavations provides much information for historical interpretation. Not only was the ratio of wild and domestic animals or of the different species of interest, but also the age and sex structure of the population by taking the function of the site into consideration. Some observations on animal teeth gave indications of distinctive handicrafts. Cut marks on cervical vertebrae of horse skeletons found as grave goods from early medieval times were considered in connection with beliefs and juridical conceptions of that time.  相似文献   
2.
本文考证了渭南、华县之间的赤水河“桥上桥”的建造年代及形成原因。通过对有关历史资料深入研究,确证下桥始建于清初(1667年),上桥则建于清朝中叶(1832年)。赤水河中上游的过度垦殖和植被破坏带来的生态环境恶化造成了下游河床泥沙淤积,形成了地面悬河,原赤水桥为泥沙淹塞,失去功能,故不得不在桥上建桥。桥上桥的形成是当地生态环境变化的结果和标志。  相似文献   
3.
This paper examines recent trends in sex ratio at birth in all the major states of India, based on three rounds of the National Family Health Survey. It finds evidence of an increase in the ratio, particularly at the second-order birth among women having a first daughter in many states in the northwestern region of the country. Also, there are signs of daughter aversion emerging in Odisha, an eastern state. Based on parity progression ratios and the trend in sex selection, an attempt is made to estimate the peak of sex ratio at birth in India. With moderate intensification in sex selection in the northwestern region, sex ratio at birth is expected to reach a peak of 117–119 males per 100 females around the period 2021–2026. If, in addition, sex selection spreads further in the southeastern region, the sex ratio at birth in India could even increase to a level of 124.  相似文献   
4.
The preference for sons in China and discrimination against girls have resulted in a male marriage squeeze. This paper develops two new indices of the sex ratio among potential first marriage partners by normalising first marriage frequencies and by eliminating the tempo effect in first marriage. Using two newly developed indices and two existing ones, the authors predict China's marriage squeeze for the period 2000–2100. The authors find that the new indices produce almost the same results as the existing ones when measuring the sex ratios of marriageable males to females. For the years 2015 to 2050, the sex ratio of potential males to females is over 1.15, and then fluctuates around 1.1 after 2060. From 2015 to 2045, China will face an annual surplus of one million males. However, if the high sex ratio at birth cannot be controlled, the male marriage squeeze will be much more severe.  相似文献   
5.
Abstract.

Australian Bureau of Statistics Total Fertility Rate (TFR) statistics are available from 1921 for Australia, and for census years between 1947 and 1966 for the states, and then on an annual basis from 1971. Using historical, statistical publications, annual TFRs for Australia and the states dating back to federation in 1901 were calculated directly in years where data are available and estimated indirectly via the standardized fertility ratio in other years. For some periods where direct TFR estimation was applied, age-specific births used in the numerators of fertility rates must be estimated from partial data. Combined with Australian Bureau of Statistics data, the authors’ estimated TFRs contribute an uninterrupted time series of national and state TFRs for Australia from 1901 to 2011.  相似文献   
6.
This paper examines John M. Keynes’s relationship with Gustav Cassel and Eli Hecksher and puts together the events related to his being awarded the 1939 Söderström Gold Medal by The Royal Swedish Academy of Sciences. The correspondence between these economists during the interwar years is detailed, with emphasis on their personal approaches to economic theory and history. Cassel’s and Heckscher’s critical reviews of Keynes’s General Theory are outlined as well. Lastly, an account is provided of the grounds for conferring the award on Keynes while also drawing attention to the conflict-laden proceedings within the Academy when the issue was under consideration by the institution. The final remarks ponder why Keynes received the prize despite the controversy among Swedish economists over the General Theory at the time.  相似文献   
7.
Tang sancai is one of the most important types of Chinese ceramics. To determine the provenance of Tang sancai is important to study ancient trade and other issues. In this paper we compare ICP-MS trace elements and TIMS Sr–Nd isotopes of visibly similar Tang sancai from two major production centres Gongxian and Yaozhou. The variation in contents/ratios of many of >40 trace elements is small for samples from Gongxian, yet is considerably bigger for that from Yaozhou. However, the variation in 87Sr/86Sr and 143Nd/144Nd isotopic ratios is very small for samples from both places. Gongxian and Yaozhou samples have distinctive Sr–Nd isotopic and trace element features despite their similarity in major elements, and these analysis data can be interpreted with geochemistry, indicating that Sr and Nd isotopes have great potential in ceramic provenance studies. The distinct characterisation of these samples provides valuable criteria for identifying provenance of Tang sancai of uncertain origin. Two modern fakes are also analysed, and they can as well be distinguished from antique Tang sancai using above criteria.  相似文献   
8.
Iron-57 Mössbauer absorption spectra have been measured for samples of obsidian from known geological flows and from archaeological site material from the western Mediterranean region. Of the four main sources available to prehistoric man it is possible to distinguish Sardinian (SA) and Pantellerian obsidian from Lipari obsidian on the basis of differences in the local atomic surroundings of iron atoms, as determined from the Mössbauer spectra. There is, however, some overlap between Lipari and Pontine Island obsidians. The Gabellotto flow on Lipari is readily identified through the presence of magnetite inclusions. The ratio of ferric to ferrous ions is found to be much higher in the surface layers (< 60 μm) than in the bulk obsidian as detected using Mössbauer backscattering.  相似文献   
9.
J. UNDERSCHULTZ 《Geofluids》2007,7(2):148-158
The impact of hydrodynamic groundwater movement on the capacity of seals is currently in debate. There is an extensive record of publication on seals analysis and a similar history on petroleum hydrodynamics yet little work addresses the links between the two. Understanding and quantifying the effects of hydrodynamic flow has important implications for calibrating commonly used seal capacity estimation techniques. These are often based on measurements such as shale gouge, clay smear or mercury porosimitry where membrane sealing is thought to occur. For standard membrane seal analysis, seal capacity is estimated by quantifying capillary pressure‐related measurements and calibrating them with a large observational database of hydrocarbon column heights and measured buoyancy pressures. The seal capacity estimation process has historically been adjusted to account for a number of different generic trapping geometries. We define the characteristics of these geometries from a hydrodynamics viewpoint in order to fine‐tune the seal capacity calibration process. From theoretical analyses of several simplified trapping geometries, it can be concluded that generally, the high pressure side of the seal should be used as the water pressure gradient with which to calculate buoyancy pressure. Secondly, trap geometries where hydrocarbon is reservoired on both sides of a fault are not useful for estimating across fault seal capacity.  相似文献   
10.
Z. Zong  X. Yin 《Geofluids》2016,16(5):1006-1016
Seismic inversion with prestack seismic data such as amplitude variation with offsets (AVO) inversion is an important tool in the estimation of elastic parameters for predicting lithology and discriminating fluid in conventional or unconventional hydrocarbon reservoirs. The product of Young's modulus and density (Young's impedance, YI) and the product of Poisson ratio and density (Poisson ratio impedance, PI) show great potential in lithology prediction and fluid discrimination of unconventional resources such as shale gas or oil. The high quality requirements for prestack data in density inversion render the estimation of YI and PI arduous and inaccurate with a conventional prestack inversion approach. In this study, a direct AVO inversion approach is proposed to estimate YI, PI, and density directly from P‐wave seismic data. The linearized P‐wave reflectivity approximate equation in terms of YI, PI, and density is initially derived. Five models, including four typical AVO classes, are utilized to verify the accuracy of the derived linearized P‐wave reflectivity equation in comparison with the exact P‐wave reflectivity equation and the frequently used linearized reflectivity approximate equation involving P‐ and S‐wave velocities and density. Parameter sensitivity analysis illustrates that YI and PI can reasonably be estimated from P‐wave reflectivity if a decorrelation scheme is utilized in the inversion algorithm. In addition, a pragmatic AVO inversion using a Bayesian scheme is suggested for the direct inversion of YI and PI from prestack seismic data. Synthetic and field data examples demonstrate the feasibility of the proposed inversion approach in the estimation of YI and PI and show the potential of this approach in fluid discrimination.  相似文献   
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