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31.
Wei She M. R. Jones Yunsheng Zhang Xing Shi 《International Journal of Architectural Heritage》2015,9(7):775-793
The Hui-style residence is an important architectural heritage of China. The hollow wall structures are widely used to build its exterior wall system. However, the thermal performance of the hollow wall is no longer able to meet the new energy-saving and environmental requirement. This article describes a laboratory study of the development of foamed mortar (FM), with the potential for use in thermal upgrading of the Hui-style hollow wall system without dramatically changing its traditional structure. The key early age, physical, mechanical and thermal properties were systematically measured. Two extended models were respectively developed to calculate compressive strength and thermal conductivity, as a function of porosity. Environment chamber test was also employed to investigate the effectiveness of this novel thermal upgrading approach and the results show that filling the voids with FM can effectively improve the overall thermal resistance of the hollow wall system by 44%, which is almost equal to the overall thermal resistance when using the more expensive commercial inorganic stucco system. In addition, the combination of these two methods yielded an overall thermal resistance of 0.701 m2·K/W, which is even higher than 0.67 m2·K/W for the code required in the hot summer/cold winter climate zone. 相似文献
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Nick Bearman Nick Jones Isabel André Herculano Alberto Cachinho Michael DeMers 《Journal of Geography in Higher Education》2016,40(3):394-408
Teaching of critical spatial thinking in higher education empowers graduates to effectively engage with spatial data. Geographic information systems (GIS) and science are taught to undergraduates across many disciplines; we evaluate how this contributes to critical spatial thinking. The discipline of GIS covers the whole process of spatial decision-making, but GIS modules often ignore the context setting of spatial problems, and just cover the technical aspects of how to use GIS software. We outline how some existing GIS practicals could be improved to focus on the development of critical spatial thinking skills, competences and abilities that are valuable to graduates. 相似文献
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Kevin B. Jones Gregory W. L. Hodgins Daniel H. Sandweiss 《The Journal of Island and Coastal Archaeology》2019,14(1):82-100
Excavations in 1970, 1996, and 1999 at Site QJ-280, Quebrada Jaguay, in southern Peru, yielded enough dateable terrestrial plant material to establish an extensive radiocarbon chronology for the site. QJ-280 is one of oldest well-dated fishing sites in the Americas: it was occupied from the terminal Pleistocene to the mid-Holocene (about 13,000–8,300 calibrated years BP) based on 42 terrestrial radiocarbon dates, encompassing the Jaguay and Machas Phases of the local archaeological sequence. In addition to the terrestrial dates, radiocarbon measurements on valves of two marine surf clam (Mesodesma donacium) individuals from a single, well-dated mid-Holocene Manos Phase archaeological context have provided insight into marine upwelling conditions during the occupation of Quebrada Jaguay. The marine reservoir age varied between 130 and 730 14C years during the brief lives of the two clams (up to 5 years each), and varied by up to 530 14C years within an individual valve, suggesting strong and variable deep marine upwelling; conditions broadly similar to those that exist in coastal Peru today. These rapid variations in marine radiocarbon age suggest that marine radiocarbon dates from environments with variable upwelling could be skewed by up to hundreds of years. 相似文献
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M. Ma G. Dong X. Liu E. Lightfoot F. Chen H. Wang H. Li M. K. Jones 《International Journal of Osteoarchaeology》2015,25(6):923-934
Intercontinental exchanges between communities living in different parts of Eurasia during the late prehistoric period have become increasingly popular as a topic of archaeological research. The Qijia culture, found in northwest China, is one of the key archaeological cultures that can shed light on trans‐Eurasian exchange because a variety of imports are found in this cultural context. These imports include new cereals and animals, which suggest that human diets may also have changed compared with previous periods. To understand human and animal diets of the Qijia culture, carbon and nitrogen isotope ratios from human and animal skeletal remains were analysed from the type site of the Qijia culture at Qijiaping. The results demonstrate that human diet at the site mainly consisted of millet and animals fed on millet. C3 cereals, such as wheat and barley, did not contribute significantly to human diet, and no isotopic differences were found between adult and subadult diets. Furthermore, three outlying human results raise the possibility of exogenous individuals, perhaps in relation to the parallel movement of animals, crops and goods. This study provides human and animal dietary information for evaluating the nature of exchange and diffusion in eastern Eurasia at this time. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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This paper presents some of the basic principles of bone fracture physics and outlines characteristics used by forensic anthropologists to distinguish gunshot trauma from blunt trauma. The fracture pattern of a cranium from a historic cemetery in Memphis, Tennessee provides an example of how the mechanism of trauma could be misinterpreted. The pattern of the perimortem fractures is indicative of gunshot trauma with a bullet entering one side of the vault and impacting the opposite side. Identification of radiating fractures, concentric heaving fractures, and observation of the direction of bevel on the fractured surfaces are essential for interpretation of the mechanism that produced the injury. 相似文献
38.
Colgi, Cajal and the Neuron Doctrine 总被引:1,自引:0,他引:1
Jones EG 《Journal of the history of the neurosciences》1999,8(2):170-178
Camillo Golgi and Santiago Ramon y Cajal shared the Nobel Prize in 1906 for their work on the histology of the nerve cell, but both held diametrically opposed views about the Neuron Doctrine which emphasizes the structural, functional and developmental singularity of the nerve cell. Golgi's reticularist views remained entrenched and his work on the nervous system did not venture greatly into new territories after its original flowering, which had greater impact than is now commonly credited. Cajal, by contrast, by the time he was awarded the Nobel Prize, was already breaking new ground with a new staining technique in the field of peripheral nerve regeneration, seeing the reconstruction of a severed nerve by sprouting from the proximal stump as another manifestation of the Neuron Doctrine. Paradoxically, identical studies were going on simultaneously in Golgi's laboratory in the hands of Aldo Perroncito, but the findings did not seem to influence Golgi's thinking on the Neuron Doctrine. 相似文献
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