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101.
In recent years, the use of carbon fiber sheet (CFS) to provide lateral confinement for enhanced ductility and strength of reinforced concrete bridge columns has been increasing. While the monotonic behavior of CFS-confined concrete has been studied extensively, its cyclic response has not been fully understood. Most of the available studies are experimental investigations, hence there is a need to develop an analytical model to simulate the experimental results. Analysis of the hysteretic behavior of CFS-retrofitted circular columns is presented in this article using the fiber element that is based on cyclic constitutive models of longitudinal reinforcement and concrete confined by both CFS and tie reinforcement. The analysis was verified based on available cyclic test data and the analysis provides good agreement with the experimental results. Results show that flexural strength and ductility of columns wrapped with CFS increases as CFS ratio increases. However, as tie reinforcement ratio increases, there is no much difference on the hysteretic response for low tie reinforcement ratios. Using the fiber element analysis, the effect of CFS retrofit on the seismic response of a 7.5 m tall prototype pier built in the 1970s to 1980s is also clarified.  相似文献   
102.
C. Mizota  T. Yamanaka 《Archaeometry》2015,57(6):1095-1103
The objective of the present study is to employ stable isotope ratio measurements (δ15N, δ34S and δ13C) of the nitrogen, sulphur and carbon in black powder (a mixture of saltpetre, native sulphur and charcoal) as a means of source identification. A sum total of 20 samples of historical black powder applicable to matchlocks were collected from six locations throughout Japan. This classic type of hand gun prevailed up to the introduction of the modern rifles, with quicker loading and higher efficiency, in the mid‐to‐late 19th century. δ13Ccharcoal carbon values showed the predominant use of C3 plants as a source material. Except for a few unusual samples with a probable exotic origin, δ15Nsaltpetre nitrogen values were largely consistent with those of domestic products using classical biotechnology. The isotopic analysis for native sulphur (δ34Snative sulphur) indicates a complicated marketing route.  相似文献   
103.
文物信息的提取与研究对于揭示古代遗物包涵的人类社会、文化等历史信息有着举足轻重的作用:一方面可以了解古代的工艺技术特征,探寻文物制作技术起源及其发展历程;另一方面可以进行病害调查分析,为保护文物提供有价值的信息。本工作以红外光谱技术为出发点,细致梳理了目前红外光谱在文物保护中的应用,包括无机质文物中青铜器、土壤、颜料、珠宝玉石,有机质文物中纸张、丝织品、彩绘胶料、有机残留物,以及保护材料。提出该技术具备应用范围广、特征性强、无损或微损样品、不受样品物态限制等优势,但同时不适合分析含水样品、定量分析时误差大、解析图谱时依靠经验等局限性。揭示显微红外光谱技术在无损分析文物方面的广大前景,为文物保护研究与实践提供参考和借鉴意义。  相似文献   
104.
The preservation of one or several historically and culturally important languages may be a salient political issue in some polities. Although they may not be used as an active means of communication, these languages can also serve a symbolic identitary function. These ‘heritage’ languages can be seen as ‘public goods’ and that even non‐speakers of these languages can have opinions regarding their importance to national identity. In the Scotland example, while Gaelic has been the focus of proactive government legislation and education initiatives, Scots is still struggling for status as a recognised language. Both languages are in some way constituent parts of Scottish identity that at times may seem in competition with one another. Using original survey data, we delve deeper into questions of language, identity and politics in Scotland. First, we describe how public opinion is divided over the importance of Gaelic and Scots to Scottish identity. Second, we use attitudes towards these languages as a dependent variable looking at Scottish identity and attachment. Finally, we use these attitudes towards Gaelic and Scots as an independent variable in models for party identification in Scotland.  相似文献   
105.
对纸质文物的科学认知是保护这类珍贵文化遗产的关键。本研究将热裂解气相色谱-质谱(Py-GC/MS)技术应用到中国传统的四类典型手工纸(竹纸、麻纸、桑皮纸和构皮纸)的分析中,结果表明竹纸中苯酚类物质含量较高,桑皮纸和构皮纸中含有大分子三萜类特征物(如β-香树脂醇、α-香树脂醇和豆甾-3,5-二烯等物质),而麻纸中则无此类特征物——利用这些特征化合物可以区分竹纸、麻纸和桑皮/构皮纸。将这一成果应用到一副清代蜡笺纸对联的分析中:确定了该书法用纸为皮纸(桑皮纸或构皮纸);检测出长链脂肪酸和醇类物质,表明蜡笺纸的制作使用了蜂蜡;检测出吡咯及其衍生物,表明该书法蜡笺纸装裱时所用的胶结材料为动物胶;另外检测到了生物碱类物质,表明该蜡笺纸使用了植物染料。综合以上研究表明,Py-GC/MS方法不仅能够确定中国传统纸质文物的纤维来源,同时可以确定纸质文物上蜡、胶结物及染料等信息;结合传统的赫兹伯格(Herzberg)染色法,进一步确定了皮纸的具体种类。蜡笺纸文物材料信息的检测识别可为文物保护与修复工作提供科学依据,此研究方法为纸质文物的科学认知提供新思路。  相似文献   
106.
Protected by the mineral matrix, bone proteins are capable of surviving inhumation periods of several hundreds or thousands of years in soil. While the preservation of the bone matrix protein, collagen I, is the prerequisite for a variety of archaeometric approaches, such as radiocarbon dating and the reconstruction of palaeodiet by stable isotope analysis, little is known about both the rate and state of preservation of non‐collagenous proteins. We succeeded in the isolation, electrophoretic separation (SDS‐PAGE, IEF) and immunological detection (radial immunodiffusion, IEF immunoblotting and ELISA) of plasma proteins preserved in archaeological human bones. However, sample preparation and electrophoretic methods had to be adapted to the specific demands of these aged proteins, since they are not only degraded and fragmented but also cross‐linked to other organic components, either indigenous to the bone or to contaminants from the burial environment. Complex decomposition phenomena are responsible for the altered mode of migration of aged proteins through a gel. After isoelectric focusing, the ancient proteins mainly concentrate below pH 4.45 in the pH‐gradient. Thus, highly negatively charged protein components have a better chance of preservation in bone after death. Isoelectric focusing with subsequent immunoblotting of ancient protein samples revealed protein patterns which showed marked charge‐modifications in comparison with those of modern human plasma proteins due to protein degradation (e.g. α2‐HS‐glycoprotein and α1‐antitrypsin). Nevertheless, in combination with different immunological analyses, previous results concerning the selective enrichment of α2‐HS‐glycoprotein in bone compared with other plasma glycoproteins could be confirmed. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
107.
在保护丝织品、纸张、竹木器、皮革及石制物时常遇到其含水率问题。目前为止,只是对保存环境量度加以测量,而缺少无损测量物本身含水率的仪器。AD—100型电磁波式含水率测量仪是专门用来测量木材含水率的,它采用高频电磁波原理,根据吸湿后介电常数发生变化测出含水率。本研究按照国家计量标准中《纸与纸板水分的测定法》,《纺织材料含水率的测定烘箱干燥法》,《皮革水分的测定》的规定把AD—100型电磁波式含水率测量仪的修正值进行校正,使每一种材质对应一个修正值,于是可以无损、简单、方便地测出已修正过的物材质含水率。对于未做过修正的物材质,可根据所述方法找出修正值达到测量其含水率的目的。  相似文献   
108.
Transparency in the location of the tooth root apex is a normal phenomenon in human ageing and provides important information for determining a person's age. The illumination of root dentine may prove useful when trying to obtain an approximate estimation of a person's age, particularly when no other data can be obtained. Regression analysis could provide a reasonably reliable means of determining an approximate age of human remains and could be used in archaeological investigations. © 1997 John Wiley & Sons, Ltd.  相似文献   
109.
Sex identifications are crucial for the understanding of the societies we study. To understand an ancient society we need to have some picture of the roles played by males and females in the society. This knowledge has often been produced by morphological sex identifications in connection with grave goods and burial finds. However, if a morphological sex identification is to be fully trusted, the human remains need to be fairly well preserved. There is also a problem in the fact that morphological traits identified in a modern material are applied on an ancient material. There is a growing difference with time and geographical distance. An alternative to morphological identification is molecular identification based on the presence or absence of a Y chromosome, but such identification has its problems too: the risk of contamination and the fact that the absence of proof is not a good female indicator. In this work we have tried to compare morphological and molecular identifications of five Neolithic individuals from the Ajvide site at Gotland in the Baltic sea. © 1997 by John Wiley & Sons, Ltd.  相似文献   
110.
"小白礁I号"清代沉船遗址位于浙江省宁波市象山县石浦镇东南约26海里的渔山列岛海域,于2008年首次发现,计划于2014年将沉船船体发掘出水。为了从多方面了解"小白礁I号"沉船的特点,考察其建造地点及造船工艺方面的有关问题,制定出水船体保护方案,为此,分别从龙骨、肋骨、隔舱板、船底板等多个部位对船体木材采样进行了种属鉴定。种属鉴定结果表明,"小白礁I号"沉船船体所用木材多为龙脑香科、马鞭草科和山榄科等阔叶硬材,且多产于东南亚热带地区而在我国较少分布,有别于我国以往考古发现的古船。"小白礁I号"沉船用材及保存状况的了解为船体发掘出水后的保护修复工作创造了非常有利的条件。  相似文献   
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