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631.
This article focuses on natural, institutional, and human factors threatening archaeological sites. A methodology is developed for assessing risks to multiple assets on a territorial scale. The methodology consists of hazard assessment, vulnerability assessment, and risk assessment. Hazard assessment involves identifying hazard exposure areas and measuring the frequency and intensity of each hazard. Vulnerability assessment incorporates examining physical, managerial, and contextual vulnerabilities of structures and remains. Geographical information systems are utilised for producing hazard, vulnerability, and risk maps. An overall picture of risks for an entire territory allows decision-makers to make informed decisions at an upstream level to limit further degradation and ensure the preservation of archaeological assets. The methodology was tested by conducting a comprehensive study in ?zmir (Turkey), where 229 archaeological sites located in 21 metropolitan districts were studied. The proposed approach provides the promise of applicability across a range of historic environments.  相似文献   
632.
东汉沅南县的设置距今已近二千年,当年该县城之故址何在?在《大清一统志》、光绪《桃源县志》、《读史方舆纪要》等古籍记载中,分别有不同说法,其中《大清一统志》的说法为近现代一些著述乃至工具书所采信。然而据《水经注》记载和其他史料考证,《大清一统志》的说法是错误的,光绪《桃源县志》亦误,唯《读史方舆纪要》之记载应为是。  相似文献   
633.
634.
Fiber internet expansion represents a path to improved economic vitality for Americans, but it is unclear who benefits from it and by how much. We examine the effects of subsidized fiber internet expansion on home prices and homebuyer demographics using data from Wisconsin and an IV approach to correct for fiber network endogeneity. We find fiber internet increases urban and rural housing values by 1.83% ($3,462) and decreases the likelihood a homebuyer is white by 2.88%, but in urban areas only. Fiber internet therefore does not appear to drive minority homebuyers away but may contribute to the urban-rural racial divide.  相似文献   
635.
本文主要运用统计学的方法,从墓地布局、墓葬的形制、葬式、器类、葬品的数量等方面,比较、阐述贾湖遗址各期不同性别和年龄群体、各个团体之间以及社会中人与人之间的差别,提出了对贾湖社会分工与分化的初步认识。  相似文献   
636.
    
The production of hydrogen by serpentinization in ultramafic‐hosted hydrothermal systems is simulated by coupling thermodynamic and dynamic modeling in the framework of a thermo‐hydraulic single‐pass model where a high‐temperature hydrothermal fluid moves preferentially through a main canal of high permeability. The alteration of ultramafic rocks is modeled with a first‐order kinetic formulation, wherein the serpentinization rate coefficient, Kr, takes the form: Kr = A exp(?α(T ? T0)2). In this formulation, α determines the temperature range of the reaction and T0 is the temperature at which the serpentinization rate reaches its maximum. This model is applied to the Rainbow hydrothermal system, which is situated on the Mid‐Atlantic Ridge, and characterized by a high temperature, a high mass flux, and a very high hydrogen concentration. The results show that a first‐order kinetic law gives a useful representation of the kinetics of serpentinization. The estimated value for the parameter A in the temperature‐dependent formulation of the serpentinization rate coefficient lies in the range (1–5) × 10?11 s?1. This effective parameter is several orders of magnitude lower than the values obtained from small grain‐size experiments, but in agreement with other published modeling studies of natural systems. Numerical simulations show that the venting site is able to produce the observed high concentration of hydrogen during the whole continuous lifetime of the Rainbow site.  相似文献   
637.
A baseline survey in 2007 characterized the physical and chemical conditions for preservation within waterlogged remains at Nantwich. Installation of eighteen dipwells has allowed a five-year monitoring programme to be conducted from 2011. Two add-on projects supplemented this monitoring programme by examining the different methods for redox measurement, and for soil moisture measurement using Time Domain Reflectometry (TDR).

Initial results show two main zones of preservation, with reducing conditions attributed to location of the deposits in the floodplain, and a second zone uphill with more variable conditions for preservation. This study shows that sediment-coring programmes combined with dipwell installations can provide useful data to assess and monitor in situ preservation conditions, which can help to formulate management strategies for conservation of waterlogged archaeological deposits. This paper focuses on the efficacy of the methodology, referencing in particular comparative monitoring techniques and lists a series of recommendations for future studies.  相似文献   
638.
A set of mainshock and aftershock data following the Chamoli earthquake of March 29, 1999, recorded at a single station viz. Gopeshwar, has been studied. Particularly, the utility of the use of aftershock/weak motion data for site characterisation in seismic microzonation studies is investigated. The analysis of aftershock and mainshock data indicates that the spectral shape and amplification is quite different during the main-shock and the aftershock. This, in turn, implies that the use of weak motion/aftershock records may lead to erroneous conclusions regarding the expected ground motion during a strong earthquake. Further, it has been shown that the site characteristics estimated from H/V ratios are not stable in the near field conditions, even for weak motion data.  相似文献   
639.
根据中国西北部喇家遗址出土的面条状遗存,面条的历史被追溯到4000年前。喇家面条被描述为由带壳的小米磨成的粉制成面团并通过反复拉伸或挤压的方法制作而成。为了了解这种面条制作工艺,我们进行了面条试制实验和煮面实验,并记录了面条中的淀粉粒在烹调过程中发生的形态变化。研究表明,纯的粟黍面粉制成的面团不能拉伸成面条,煮过的粟黍淀粉粒形态也与喇家"面条"遗存中的"淀粉粒"不符。我们认为来自喇家"面条"的小米颖壳植硅体及似淀粉粒的颗粒是否来自面条需要进一步研究。  相似文献   
640.
白九江 《江汉考古》2003,1997(2):46-54
由于鄂西峡江地区的新石器时代晚期遗存面貌复杂,对于该地区是否存在屈家岭化长期以来存在激烈的争论。本选取湖北宜昌中堡岛作为典型遗址入手,运用化因素分析法,对该遗址的新石器时代遗存材料进行了分析,区分出大溪、屈家岭、哨棚嘴三种化因素,并进而对三种化因素的关系进行了探讨,其结论对于该地区相当于屈家岭化时代遗存的辨识和定性具有重要的参考作用。  相似文献   
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