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1.
张墨 《史学月刊》2002,(4):26-34
哀公十年(前485年),吴徐承帅舟师沿海北上攻齐进行海战事,似难确认。襄公二十四年(前549),楚以舟师伐吴,是为史籍明确记载的第一次动用舟师的征战,但恐难排除此前已发生过动用舟师征战的事实,是故中国古代海军的产生(形成)时间,尚需进一步科学、准确论证。“海军”是个历史范畴,在不同的历史时期具有不同的形态,称谓也有所变化。中国古代海军的主要称谓有舟师、楼船军、水军、水师等。  相似文献   
2.
The presence of DNA has been demonstrated in the cell nuclei of an ancient Egyptian mummy fragment. When extracted, this DNA proved to be degraded to a considerable extent and chemically modified. However, the preservation of nucleic acids in this specimen suggests that applying recombinant DNA techniques to the study of ancient mummified tissues might prove to be a fruitful future area of research.  相似文献   
3.
本文通过 X 射线衍射(XRD)、差热分析(DTA)、发射光谱分析(ESA)、扫描电镜(SEM)和能量色散 X 射线分析(EDAX)的方法,对古耀州青瓷所用原料及其矿物组成,古瓷器的烧成温度和显微结构进行了分析研究。得出耀瓷乃是使用当地高岭石和伊利石粘土矿物为原料烧制而成,烧成温度在1200℃以上的结论.  相似文献   
4.
慈利白公城遗址历史悠久,具有重要的考古价值。该遗址出土了大量木质井壁及少量其他木质文物,为了解这些木材的特点,以及为木材保护提供相关的参考,通过徒手切片,并利用光学显微镜对该遗址出土的10件木质样品进行鉴定。结果表明其中1件为无患子(Sapindus. mukorossi Gaertn.),1件为冷杉(Abies fabri(Mast.)Craib),2件为湖南杨桐(Adinandra. acutifolia Hand.-Mazz.),2件为香椿(Toona sinensis A. Juss.),4件为润楠(Machilus pingii Cheng ex Yang)。通过实验结果,初步推测井壁的制作在当时是比较重要的工作,此时已经在选择性地使用木质井壁原料。从树种适宜生长的环境上看,同时期该遗址附近可能是以阔叶材为主的针阔叶混交林,气候温暖湿润。  相似文献   
5.
Critical physical geography (CPG) calls for integrative research on material landscapes and the socio-political dynamics of scientific knowledge production. Network analysis, a rich tradition of tools and approaches for analyzing relational information, has seen little use in the CPG literature to date. This represents a fruitful opportunity, as many of CPG's core interests—knowledge politics, histories of scientific concepts, and ecosocial relations—can be effectively analyzed using network techniques. In this article, I argue for adapting network approaches to CPG. First, I provide an overview of various network concepts, approaches, and their origins. I then discuss bibliometric network techniques for “science mapping” including co-word, co-authorship, and citation analyses. Next, I describe discourse network analysis, a recent mixed-method approach from political science. Finally, I discuss overlaps with emerging approaches from qualitative and visual network analysis. In each section, I provide existing and hypothetical examples, as well as software and visualization techniques, that demonstrate how network approaches could add new insights to CPG and related scholarship. Linking CPG with the diverse traditions of network analysis has the potential to produce new empirical understandings and bring the field into conversation with a growing body of research that spans the social sciences, natural sciences, and humanities.  相似文献   
6.
古铜矿遗址围岩表层有害生物的防治   总被引:3,自引:0,他引:3  
铜绿山古铜矿遗址地处长江中游地区、空气湿度大、围岩表层有害生物成片生长蔓延,对遗址的长期保护造成极大威胁。对此采取了改变遗址的环境条件、喷涂消杀药品的方法,消除了围岩表层有害生物的危害。经过一年半的观察表明该方法是可行的。  相似文献   
7.
Significant advances in our understanding of ancient agricultural practices in the Americas have been made in recent years. This review of the literature focuses on studies published between 1987 and early 1994. Issues pertaining to the transition from foraging to farming include the habitability of the American tropics prior to the development of agriculture, theories on plant domestication and the origins of agriculture, regional syntheses of agricultural development, and the origin, evolution, and dissemination of domesticates in the Americas. Other topics reviewed include new techniques that have recently been applied to the study of prehistoric agriculture in the Americas, various approaches to the study of agricultural change, and ways in which research on ancient agricultural practices is being applied in modern experimental agriculture and rural development projects.  相似文献   
8.
We use trace element discrimination diagrams to provide a geochemical fingerprint for Tufo Lionato, the volcanic rock most commonly used in the ancient Roman dimension stone technique. Based on the comparison of their geochemical signatures, we identify different rock facies of Tufo Lionato employed since the fourth to third centuries and through the second century bce in the construction of the temples of the Area Sacra di Largo Argentina. These rock facies correspond to two previously identified building stones: Aniene Tuff and Monteverde Tuff, named after their supposed source areas located in the Aniene River Valley and in the homonymous locality of the Tiber River Valley, respectively. However, the results of our study demonstrate previous misidentification of these volcanic rocks in the different construction phases of Temple C, providing a revision of the dating system currently accepted for the diffusion of Tufo Lionato architecture. We show that the Aniene facies has been exploited since the end of the fourth century bce and that it was employed along with Tufo Giallo della Via Tiberina in the podium and staircase of Temple C, whereas observations at Largo Argentina suggest that the ‘Monteverde Tuff’ was only sporadically used in the early phases of the dimension stone construction technique.  相似文献   
9.
A human skull, buried about 2500 years ago in a Bronze Age cemetery at Jinggouzi, a site of an important ethnic group in ancient China, appeared to have characteristics of fibrous dysplasia. The CT images indicated a reduction in bone density and relatively homogeneous lesions. More features were revealed using CT reconstruction techniques. Lesions seen in low‐magnification images using a 3D deep‐field microscope had an irregular honeycomb‐like structure. At higher magnification, the trabeculae morphology and the gaps between the trabeculae were irregular and varied in size and shape. Paraffin‐embedded specimens stained with HE showed trabeculae with tortuous irregular arrangements varying in shape and width. The irregular trabeculae of woven bone has been described as having fibrous dysplasia. Molecular analysis of the GNAS gene indicated no mutation. This provides a non‐invasive approach for us to make more comprehensive diagnoses and to assist research into ancient human diseases.  相似文献   
10.
At a moment when disciplinary attentions are turning to the digital as a subject and object of geographic inquiry, we consider enduring contours and new directions in feminist digital geographies scholarship. We revisit the centrality of feminist critiques of Science to critical digital geographies and their predecessors, identifying axes of scholarly engagement that have emerged from feminist theory and praxis. Simultaneously, we acknowledge the resounding whiteness and heteronormativity of these theoretical origins. In the second half of the article, we trace new horizons of contemporary digital geographies scholarship that engage queer and critical race theory, postcolonial feminism, and black and queer code studies. These theoretical moves give voice to longstanding silences and are indispensable to a political and ethical digital geographic scholarship and praxis, as well as to re-making our technologies and ourselves as digital subjects.  相似文献   
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